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  • 251.
    Schwarz, Sebastian
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gaining Depth: Time-of-Flight Sensor Fusion for Three-Dimensional Video Content Creation2014Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The successful revival of three-dimensional (3D) cinema has generated a great deal of interest in 3D video. However, contemporary eyewear-assisted displaying technologies are not well suited for the less restricted scenarios outside movie theaters. The next generation of 3D displays, autostereoscopic multiview displays, overcome the restrictions of traditional stereoscopic 3D and can provide an important boost for 3D television (3DTV). Then again, such displays require scene depth information in order to reduce the amount of necessary input data. Acquiring this information is quite complex and challenging, thus restricting content creators and limiting the amount of available 3D video content. Nonetheless, without broad and innovative 3D television programs, even next-generation 3DTV will lack customer appeal. Therefore simplified 3D video content generation is essential for the medium's success.

    This dissertation surveys the advantages and limitations of contemporary 3D video acquisition. Based on these findings, a combination of dedicated depth sensors, so-called Time-of-Flight (ToF) cameras, and video cameras, is investigated with the aim of simplifying 3D video content generation. The concept of Time-of-Flight sensor fusion is analyzed in order to identify suitable courses of action for high quality 3D video acquisition. In order to overcome the main drawback of current Time-of-Flight technology, namely the high sensor noise and low spatial resolution, a weighted optimization approach for Time-of-Flight super-resolution is proposed. This approach incorporates video texture, measurement noise and temporal information for high quality 3D video acquisition from a single video plus Time-of-Flight camera combination. Objective evaluations show benefits with respect to state-of-the-art depth upsampling solutions. Subjective visual quality assessment confirms the objective results, with a significant increase in viewer preference by a factor of four. Furthermore, the presented super-resolution approach can be applied to other applications, such as depth video compression, providing bit rate savings of approximately 10 percent compared to competing depth upsampling solutions. The work presented in this dissertation has been published in two scientific journals and five peer-reviewed conference proceedings. 

    In conclusion, Time-of-Flight sensor fusion can help to simplify 3D video content generation, consequently supporting a larger variety of available content. Thus, this dissertation provides important inputs towards broad and innovative 3D video content, hopefully contributing to the future success of next-generation 3DTV.

  • 252.
    Sefyrin, Johanna
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Sitting on the Fence – Critical Explorations of Participatory Practices in IT Design2010Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis is about participation in IT design. The problem background that I have outlined is that information technologies have far reaching consequences for societies and for individuals, and that the design of information technologies is one among many practices that shape the world in which we live. From a democratic point of view it is crucial that also women should be involved in these reality producing practices. In relation to this there are at least two stories about women’s participation in IT design; one about their absence from IT design, and one about their inclusion therein. Based on this problem background the purpose of my research is to critically explore participatory IT design practices, with a special focus on gender, power and knowledge. In order to fulfil the purpose I have three research questions: Who participated in the IT design practices? How did knowledge come into being in these practices? How was responsibility enacted?

    My frame of reference is based on two research fields. One is Participatory Design (PD) with its focus on practitioners as co-designers in IT design practices, and the other is feminist technoscience which focuses on theories, methods, approaches, knowledge processes, and gender in technoscience practices. These two frameworks shares an interest in power relations and democratic participation in IT design. My empirical material was gathered with the help of ethnographic methods, and comes from a large IT design project in a Swedish government agency. The project was an eGovernment project, and a central objective was to rationalise the business. My focus was some (women) administrative officers who participated as business process analysts. This material was analysed with the help of feminist technoscience methodologies, foremost agential realism and diffraction.

    My thesis is based on five research papers, and the results of these are discussed and related to the research questions and the purpose. Based on an expanded notion of IT design and of participation in IT design, I argue that the administrative officers in the IT design project participated as central actors in the project. These administrative officers were able to participate within the context provided by various entangled sociomaterial practices, such as the project method, boundaries between business and IT, gendered divisions of labour, eGovernment, rationalisation, the project objectives, and an innovation practice. I also argue that in the project knowledge did not simply exist, but came into being as a result of entanglements of these sociomaterial practices, foremost the project objectives and the method. As a result of the reconfigured knowledge the administrative officers were removed to the periphery of the project. An additional argument is that with participation comes responsibility, and that responsibility is related to agency. Responsibility was enacted in and as a result of entangled sociomaterial practices. In this project the administrative officers were given and took a lot of responsibility within the boundaries provided by the sociomaterial practices, but they also worked to widen their agency and thus extend their responsibilities in the project. In relation to gender my argument is that the administrative officers in the project – who were women – participated as central actors, but they were also marginalised and made invisible. Thus in this IT design project women were included as central actors.

    As one of my contributions to PD and to feminist technoscience I want to underscore the importance of sociomaterial practices in IT design, such as IT design methods, and project objectives. These may act to restrict actors’ possibilities to act and to exert influence. Another is that knowledge in IT design practices come into being and are reconfigured as a consequence of intra-acting sociomaterial practices. Reconfigurations of knowledge might shift the power balance among actors in IT design projects and marginalise previously central actors. Responsibility too comes into being, or is enacted, in entangled sociomaterial practices. Furthermore responsibility in IT design is closely related to agency and participation, and widened agency might lead to extended possibilities to take responsibility. Additionally if positions in IT design are understood as fixed, they might make invisible more shifting and intricate professional relations and activities, and once these become visible, more women may become visible as central actors in IT design. A further contribution is that an expanded notion of IT design and participation might make women visible as central participants in IT design and in eGovernment. However, also central participants may become marginalised, as happened in this project.

  • 253.
    Shahzad, Khurram
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för elektronikkonstruktion.
    Energy Efficient Wireless Sensor Node Architecture for Data and Computation Intensive Applications2014Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Wireless Sensor Networks (WSNs), in addition to enabling monitoring solutions for numerous new applications areas, have gained huge popularity as a cost-effective, dynamically scalable, easy to deploy and maintainable alternatives to conventional infrastructure-based monitoring solutions.

    A WSN consists of spatially distributed autonomous wireless sensor nodes that measure desired physical phenomena and operate in a collaborative manner to relay the acquired information wirelessly to a central location. A wireless sensor node, integrating the required resources to enable infrastructure-less distributed monitoring, is constrained by its size, cost and energy. In order to address these constraints, a typical wireless sensor node is designed based on low-power and low-cost modules that in turn provide limited communication and processing performances. Data and computation intensive wireless monitoring applications, on the other hand, not only demand higher communication bandwidth and computational performance but also require practically feasible operational lifetimes so as to reduce the maintenance cost associated with the replacement of batteries. In relation to the communication and processing requirements of such applications and the constraints associated with a typical wireless sensor node, this thesis explores energy efficient wireless sensor node architecture that enables realization of data and computation intensive applications.

    Architectures enabling raw data transmission and in-sensor processing with various technological alternatives are explored. The potential architectural alternatives are evaluated both analytically and quantitatively with regards to different design parameters, in particular, the performance and the energy consumption. For quantitative evaluation purposes, the experiments are conducted on vibration and image-based industrial condition monitoring applications that are not only data and computation intensive but also are of practical importance.

    Regarding the choice of an appropriate wireless technology in an architecture enabling raw data transmission, standard based communication technologies including infrared, mobile broadband, WiMax, LAN, Bluetooth, and ZigBee are investigated. With regards to in-sensor processing, different architectures comprising of sequential processors and FPGAs are realized to evaluate different design parameters, especially the performance and energy efficiency. Afterwards, the architectures enabling raw data transmission only and those involving in-sensor processing are evaluated so as to find an energy efficient solution. The results of this investigation show that in-sensor processing architecture, comprising of an FPGA for computation purposes, is more energy efficient when compared with other alternatives in relation to the data and computation intensive applications.

    Based on the results obtained and the experiences learned in the architectural evaluation study, an FPGA-based high-performance wireless sensor platform, the SENTIOF, is designed and developed. In addition to performance, the SETNIOF is designed to enable dynamic optimization of energy consumption. This includes enabling integrated modules to be completely switched-off and providing a fast configuration support to the FPGA.

     In order to validate the results of the evaluation studies, and to assess the performance and energy consumption of real implementations, both the vibration and image-based industrial monitoring applications are realized using the SENTIOF. In terms of computational performance for both of these applications, the real-time processing goals are achieved. For example, in the case of vibration-based monitoring, real-time processing performance for tri-axes (horizontal, vertical and axial) vibration data are achieved for sampling rates of more than 100 kHz.

    With regards to energy consumption, based on the measured power consumption that also includes the power consumed during the FPGA’s configuration process, the operational lifetimes are estimated using a single cell battery (similar to an AA battery in terms of shape and size) with a typical capacity of 2600 mA. In the case of vibration-based condition monitoring, an operational lifetime of more than two years can be achieved for duty-cycle interval of 10 minutes or more. The achievable operational lifetime of image-based monitoring is more than 3 years for a duty-cycle interval of 5 minutes or more. 

  • 254.
    Shehata, Adam
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Media Matter: The Political Influences of the News Media2010Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
  • 255.
    Shen, Wei
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    A Protocol Framework for Adaptive Real-Time Communication in Industrial Wireless Sensor and Actuator Networks2014Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Low-power and resource-constrained wireless technology has been regarded as an emerging technology that introduces a paradigm shift in a wide range of applications such as industrial automation, smart grid, home automation and so on. The automation industry has significant contributions to economic revenues, job opportunities and world-class research. The low-power and resource-constrained wireless technology has brought new opportunity and challenges for industrial automation. The solutions of such wireless technology offer benefits in relation to lower cost and more flexible deployments/maintenances than the wired solutions, and new applications that are not possible with wired communication. However, these wireless solutions have been introducing new challenges. Wireless links are inherently unreliable, especially in industrial harsh environment, and wireless interference makes the problem even worse. Low-power consumption is required and real-time communication is generally crucial in industrial automation applications.

    This research work addresses that industrial wireless sensor and actuator network (IWSAN) should even be designed to provide service differentiation for wireless medium access and adapt to link dynamics for scheduling algorithms on top of real-time services. Specifically, exceeding the required delay bound for unpredictable and emergency traffic in industrial automation applications could lead to system instability, economic and material losses, system failure and, ultimately, a threat to human safety. Therefore, guaranteeing the timely delivery of the IWSAN critical traffic and its prioritization over regular traffic (e.g. non-critical monitoring traffic) is a significant topic. In addition, the state-of-the-art researches address a multitude of objectives for scheduling algorithms in IWSAN. However, the adaptation to the dynamics of a realistic wireless sensor network has not been investigated in a satisfactory manner. This is a key issue considering the challenges within industrial applications, given the time-constraints and harsh environments.

    In response to those challenges, a protocol framework for adaptive real-time communication in IWSAN is proposed. It mainly consists of a priority-based medium access protocol (MAC) and its extension for routing critical traffic, a hybrid scheme for acyclic traffic, and adaptive scheduling algorithms. To the best of our knowledge, the priority-based MAC solution is the first priority-enhanced MAC protocol compatible with industrial standards for IWSAN. The proposed solutions have been implemented in TinyOS and evaluated on a test-bed of Telosb motes and the TOSSIM network simulator. The experimental results indicate that the proposed priority-based solutions are able to efficiently handle different traffic categories and achieve a significant improvement in the delivery latency. The hybrid scheme for acyclic traffic increases the throughput and reduces the delay compared to the current industrial standards. Numerical results show that the adaptive scheduling algorithms improve the quality of service for the entire network. They achieve significant improvements for realistic dynamic wireless sensor networks when compared to existing scheduling algorithms with the aim to minimize latency for real-time communication.

  • 256.
    Sidén, Johan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    On the Design, Characterization and Optimization of RFID Tag Antennas2007Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Remotely read electronic identification tags are establishing as the standard method of identifying objects in transport logistcs. They are referred to as RFID tags and with successful research and development they are likely to one day replace all of todays barcodes, found on a wide variety of items and objects. As RFID systems consist of many different parts spanning over just as many academic subjects, this thesis investigates some of the main issues regarding RFID tag antennas. Large focus is put on performance and cost optimization of relatively simple one‐layer antennas, suitable for mass production in commercial printing presses using electrically conductive ink. Examples of specially designed antennas include ones that can operate upon metallic objects and antennas that can be physicall bent. It is also shown how RFID tag antennas that will be widely exposed to the human eye can include a commercial value by letting heir geometric design originate from group insignias and company logos. The thesis also presents a solution of how pairs of ordinary low cost RFID tags can be used as remotely read moisture sensors.

  • 257.
    Silfver, Jeanette
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    G-convergence and Homogenization Involving Operators Compatible with Two-scale convergence2007Doktorsavhandling, monografi (Övrigt vetenskapligt)
  • 258.
    Sjöberg, Jessica C
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    High Consistency Mechanical Treatment of Kraft Pulps under Steam Pressurised Conditions - Effects on Fibre and Sheet Properties2007Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
  • 259.
    Sjöblom, Lena-Mari
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för hälsovetenskap.
    Närstående i den psykiatriska vården: En kvalitativ studie om erfarenheter av närståendes delaktighet2010Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
  • 260.
    Sjöström, Rita
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för hälsovetenskap.
    Multidisciplinary rehabilitation in musculoskeletal disorders: Quantitative and qualitative follow-up studies2009Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The primary aim of this investigation was to evaluate a seven-week

    multidisciplinary rehabilitation programme, with emphasis on

    musculoskeletal disorders, for working-age people, by assessments at the

    start and end of the rehabilitation programme, and at follow-up

    examinations 6, 12 and 24 months after completion of the programme. A

    further aim was to explore the experiences of people not returning to work

    during a period of six years after participation in an extensive

    multidisciplinary rehabilitation programme.

    Sixty participants, 40 women and 20 men (mean age 46.8 ± SD 7.9), with

    musculoskeletal disorders, mainly neck and back pain, participated in a 7-

    week rehabilitation programme which was based on a combination of

    theoretical and practical education, physical activities, relaxation and

    individual guidance. Before and after the programme and at the follow-up

    occasions all participants were evaluated with the Global Self-Efficacy

    Index (GSI), Hospital Anxiety and Depression Scale (HAD), and Stress test

    (Study I). A group of participants who were still full-time sick-listed (Group

    I) at the end of the study period were compared with participants who were

    part-time or not sick-listed (Group II) at the end of the study period (II, III,

    IV). They were evaluated with the Disability Rating Index (DRI), with the

    Pain Intensity Rating Index on a visual analogue scale (VAS) (II, III)),

    mobility tests (III), GSI (III), HAD, and a stress test (IV). Seven women

    (median age 48 years) and three men (53 years) (Group I) were interviewed

    and the interviews were analysed by manifest content analysis (V).

    At the 2-year follow-up full-time sick leave, anxiety, depression and selfexperienced

    stress had decreased in both sexes. They also showed increased

    quality of life (QoL) (I). In participants with full-time sick leave (Group I),

    self-experienced physical disability and pain ratings were high and showed

    no decrease up until the 2-year follow-up. In participants with part-time or

    no sick leave (Group II), physical disability and pain ratings decreased

    gradually throughout the 2-year follow-up period (II). Cervical and

    thoracolumbar spine range of motion (ROM) was lower in Group I than in

    Group II from the start of rehabilitation to a 2-year follow-up. Only Group

    II showed a temporal improvement in ROM. No changes in DRI, VAS or

    GSI were found in parallel with corresponding temporal changes in any of

    the ROM (III). Group I experienced no change in anxiety or depression

    during the study period, in contrast to Group II, in which this decreased.

    Decreased stress was found in both groups (IV). Group I described

    perceived barriers to and possibilities of returning to work, and also gave

    information on what strategies they used, to cope with everyday life (V).

    The majority of the participants improved and they continued to be

    physically active, their QoL improved, and most participants returned to

    work. Ten of the participants, however, were on full-time sick leave

    throughout the whole study period, with high self-experienced physical

    disability, high pain rating and no improvement in anxiety and depression.

    They experienced barriers to re-entering the labour market as consequences

    of physical symptoms and fatigue. But they also believed in possibilities of

    returning to work if they could get a modified job adapted to their own

    capacity.

    Thus, persons with severe disability and pain did not improve by

    rehabilitation in this project. New methods of treatment have to be

    developed for improvement of symptoms resulting in reduction of

    functional impairment and a consequent need for sick leave.

  • 261.
    Skoog Waller, Sara
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för psykologi och socialt arbete.
    Estimation of Speaker Age: Effects of Speech Properties and Speech Material2019Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The aim of this thesis was to investigate factors related to accuracy in estimation of speaker age and the role of certain speech properties in perception and manipulation of speaker age, as well as their interaction with the speech material that the age estimates were based on. This thesis consists of three studies.

    In Study 1 the aim was to investigate the role of speech rate as well as the level of accuracy in estimation of speaker age, depending on linguistic variation in the speech material (read versus spontaneous speech). In two experiments, one using read speech from 36 female and male speakers in three age groups (younger: 20-25 years, middle aged: 40-45 years and older:60-65 years old) as stimuli, and the other using spontaneous speech from the same speakers, we investigated how changes in speech rate influenced listeners’ age estimates of young adult, middle aged and older speakers. The results revealed that listeners estimated the speakers as younger when speech rate was faster than normal and as older when speech rate was slower than normal. This speech rate effect was slightly greater in magnitude for older speakers in comparison with younger speakers, suggesting that speech rate may gain greater importance as a perceptual age cue with increased speaker age. This pattern was more pronounced in Experiment 2, in which listeners estimated age from spontaneous speech. Faster speech rate was associated with lower age estimates, but only for older and middle aged speakers. Taken together, speakers of all age groups were estimated as older when speech rate was decreased, except for the youngest speakers in Experiment 2. The absence of a linear speech rate effect in estimates of younger speakers, for spontaneous speech, implies that listeners use different age estimation strategies or cues (possibly vocabulary) depending on the age of the speaker and the spontaneity of the speech.

    Study 2 investigated how speakers spontaneously manipulate two age related vocal characteristics (fundamental frequency and speech rate) in attempts to sound younger versus older than their true age, and if the manipulations correspond to actual age related changes in fundamental frequency (F0) and speech rate. The study also aimed at determining how successful vocal age disguise is by asking listeners to estimate the age of generated speech samples and to examine whether or not listeners use F0 and speech rate as cues to perceived age. Participants from three age groups (20–25, 40–45, and 60–65 years) agreed to read a short text under three voice conditions. There were 12 speakers in each age group (six women and six men). They used their natural voice in one condition, attempted to sound 20 years younger in another and 20 years older in a third condition. Sixty listeners were exposed to speech samples from the three voice conditions and estimated the speakers’ age. Each listener was exposed to all three voice conditions. The results indicated that the speakers increased F0 and speech rate when attempting to sound younger and decreased F0 and speech rate when attempting to sound older. The voice manipulations had an effect on age estimation in the sought-after direction, although the achieved mean effect was only 3 years, which is far less than the intended effect of 20 years. Moreover, listeners used speech rate, but not F0, as a cue to speaker age. It was concluded that age disguise by voice can be achieved by naïve speakers even though the perceived effect was smaller than intended.

    In Study 3 the aim was to study confidence and accuracy in estimates of speaker age and whether confidence can serve as an indicator of estimation accuracy. Two experiments were performed investigating accuracy in estimation of speaker age, as well as the listeners’ confidence that their estimates were correct. In Experiment 1 listeners made age estimates based on spontaneous speech while in Experiment 2 the estimates were based on read speech. The purpose of the study was to explore differences in accuracy and confidence depending on speech material, speaker characteristics (gender and age) and listener gender. Another purpose was to examine the realism in the listeners’ confidence ratings in estimations of spontaneous versus read speech. No differences in accuracy or confidence were found due to speech material type. Although accuracy was higher in estimates of male speakers, confidence was higher in estimates of female speakers. As the correlation between confidence and accuracy was weak, it was concluded that confidence should not be relied on as an indicator of accuracy in estimation of speaker age.

    The three studies in this thesis provide some insight into different aspects of perception of speaker age. Possible implications of the results and suggestions for further research are discussed.

  • 262.
    Skotnes, Liv Heidi
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för hälsovetenskap.
    Forstyrrelser i de nedre urinveier hos gamle på sykehejm: urininkontinens, residualurin, urinveisinfeksjon, samt inkontinenspleie2012Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [no]

    Det overordnede målet med denne avhandling var å få en oversikt over ulike forstyrrelser i de nedre urinveier hos gamle. Dernest var målet å beskrive oppfatninger og barrierer som influerte på personalets muligheter for å gi riktig inkontinenspleie til beboere i sykehjem. Avhandlingen består av en kvantitativ studie (artikkel I, II, III), og en kvalitativ studie (artikkel IV). Artikkel I var en tverrsnittstudie. Artikkel II og III var en prospektiv tidsdesignstudie med en oppfølgingsperiode på ett år. 183 beboere fra seks sykehjem deltok i den kvantitative studien. I artikkel I ble prevalensen av urininkontinens hos norske sykehjembeboere evaluert. I tillegg ble det forsøkt å identifisere faktorer som var assosiert med urininkontinens i denne populasjonen. I artikkel II ble det undersøkt om residualurin var en risiko for å utvikle urinveisinfeksjon hos gamle på sykehjem. I artikkel III ble det undersøkt om bleiebruk per døgn er en pålitelig metode for å kvantifisere urininkontinens hos sykehjemsbeboere. Det ble også studert om det var sammenheng mellom urinveisinfeksjon, bleiebruk per døgn og væskeinntak. I den kvalitative studien var målet å identifisere oppfatninger og barrierer som influerte på pleiernes muligheter for å gi riktig inkontinenspleie. Fem avdelingsledere, fem sykepleiere og fem hjelpepleiere ble intervjuet i til sammen tre fokusgruppeintervjuer.Analysen i artikkel I viste at 122 beboere (69 %) var inkontinent for urin og 144 (83 %) brukte bleier. 14 % brukte bleier for sikkerhets skyld. Lav ADL-skår, demens og urinveisinfeksjon var assosiert med urininkontinens (P = <0.01). I artikkel II hadde 98 beboere (63.3 %) residualurin mindre enn 100 ml, og 52 (34.7 %) hadde residualurin på 100 ml eller større. I løpet av oppfølgingsperioden hadde 51 beboere (34 %) utviklet en eller flere urinveisinfeksjoner. Forekomsten av urinveisinfeksjon var høyere hos kvinnene enn hos mennene (40.4 % versus 19.6 %; P = 0.02). Det ble ikke funnet noen signifikant forskjell i gjennomsnittlig residualurin mellom beboere som utviklet og som ikke utviklet urinveisinfeksjon (79 versus 97 ml, P = 0.26). Residualurin på 100 ml eller større var ikke assosiert med større risiko for utvikling av urinveisinfeksjon.I artikkel III brukte 118 (77 %) av beboerne bleier. Bleiebruk per døgn er et upålitelig mål på urininkontinens hos beboere i sykehjem. Beboere som brukte bleier hadde en økende risiko for å utvikle urinveisinfeksjon sammenlignet medvibeboere som ikke brukte bleier (41 versus 11 %; P = 0.001). Daglig væskeinntak var ikke assosiert med urinveisinfeksjoner (P = 0.46). Antall bleieskift viste ingen korrelasjon med risikoen for utvikling av urinveisinfeksjon (P = 0.62). Bleiene som beboerne brukte per døgn, viste stor variasjon i inkontinensvolum. I den kvalitative studien ledet innholdsanalysen fram til tre emner og åtte kategorier. Det første emnet, Oppfatninger og barrierer assosiert med beboerne, inneholdt en kategori ”fysiske og kognitive problemer”. Det andre emnet, Oppfatninger og barrierer assosiert med personalet, inneholdt tre kategorier: ”manglende kunnskaper”, ”holdninger og tro” og ”manglende tilgjengelighet”. Det tredje emnet, Oppfatninger og barrierer assosiert med den organisatoriske kulturen, inneholdt fire kategorier: ”rigide rutiner”, manglende ressurser”, ”manglede dokumentasjon” og ”svakt lederskap”. Resultatene i denne avhandlingen viser at forekomsten av urininkontinens i sykehjem er høy. Absorberende produkter er hyppig brukt uten en kjent historie av urininkontinens. Fysisk svekkelse, demens og urinveisinfeksjon er assosiert med urininkontinens. Residualurin er vanlig hos beboere i sykehjem. Det ble ikke funnet noen sammenheng mellom residualurin og urinveisinfeksjon. Bruk av absorberende bleier er assosiert med økt risiko for utvikling av urinveisinfeksjon. Bleiebruk per døgn og væskeinntak var ikke korrelert med økt risiko for utvikling av urinveisinfeksjon. Bleiebruk per døgn er et upålitelig mål på urininkontinens hos beboere i sykehjem. Funnene fra den kvalitative studien viser at det er mange barrierer som influerer på personalets evne til å gi riktig inkontinenspleie til beboere i sykehjem. Det kan likevel se ut som om personalets oppfatninger og holdninger, samt manglende kunnskaper om urininkontinens, er de viktigste barrierene for å gi riktig inkontinenspleie.

  • 263.
    Solum Myren, Gunn Eva
    Mittuniversitetet, Fakulteten för humanvetenskap, Avdelningen för omvårdnad.
    Dagaktivitetstilbud for personer med demens som bor hjemme: ”Dagen i dag den kan bli vår beste dag”2018Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The aim of the thesis was to examine how persons with dementia in who live at home experience day care services and what the services mean to them, their relatives and care staff. For persons with dementia, everyday life often lacks social and sensory stimuli, and research has shown that their relatives experience a burden of care that strains their quality of life. In response, more knowledge is necessary about how municipal services in should be designed to ensure that persons with dementia can stay at home for as long as possible. From 2020, municipalities in Norway, will have a statutory duty to offer day care services to persons with dementia. The thesis is based on four qualitative studies. In study I, fieldwork comprised observations and informal conversations with persons with dementia (participants) who receive care from two day care services and staff. Study II involved semi-structured interviews and study III, narrative interviews with relatives, whereas study IV involved semi-structured interviews with care staff. In study I, results revealed that location and buildings affected the inclusion of participants in activities. Where as homey, familiar environments contributed to greater activity among participants, institutional environments contributed to greater passivity, at least from the perspective of participants and staff. In turn, the meaningfulness of participants’ everyday lives depended on staff adaptiveness in exercising person-centred care. In study II, relatives of persons with dementia reported that the pre- and post-diagnosis periods were challenging for them and that the day care services, especially the daily routines that they established, were thus exceptionally meaningful. The relatives reported not only that could they afford to rest on days when the persons with dementia received day care services but that the participants experienced those days to be meaningful as well. At the same time, they reported struggling with deciding for how long it would be reasonable for the persons with dementia to live at home. In study III, results revealed that living with persons with dementia affected the everyday lives of spouses and cohabitants, who had to assume new roles and adapt to living lives full of commitment, singularity, anxiety and oneliness. Spouses and cohabitants not only sought to optimally manage their domestic arrangements but also conceal from others how they felt or thought about their situations. To those ends, day care services therefore helped them to persevere in caring for and living with their loved ones, as well as afforded them time to pursue their personal interests. Being visited by day care staff prevented them from having to ask for help because staff members were there to offer it instead.…Last, during study IV, staff reported striving to implement person-centred care by ensuring the dignity of participants and their relatives and facilitating meaningful activities according to individual needs. However, staff also reported facing various barriers in realising person-centred care, including staff shortages, different levels of functioning among participants and limitations in the design of spaces and their location. When developing day care services, it is important to consider both the physical design and location of buildings in which care will be offered. Person-centred care can guide the organization of adequate, tailored day care services able to afford persons with dementia meaningful everyday lives.

  • 264.
    Sparf, Jörgen
    Mittuniversitetet, Fakulteten för humanvetenskap, Avdelningen för samhällsvetenskap.
    Tillit i samhällsskyddets organisation: Om det sociala gränssnittet i risk- och krishantering mellan kommunen och funktionshindrade2014Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Systemet för samhällsskydd och beredskap i Sverige har sedan 1990-talet genomgått en rad förändringar gällande juridik, organisering och ansvar. Framför allt har kommunernas ansvar inom området ökat och systemet har kommit att bli mer beroende av aktörer i lokalsamhället. Dessutom har den enskilde individen fått ett ökat ansvar och är idag en självklar aktör i systemet. De i området styrande principerna om ansvar, likhet och närhet föreskriver att störningar i kommunal verksamhet ska hanteras av de roller som bedriver verksamheten i normala fall. Det innebär att störningar eller kriser i en verksamhet som exempelvis den kommunala omsorgen ska hanteras och lösas av den ordinarie personalen. Systemets ordning i kombination med principerna gör därför att frågor om säkerhet och trygghet för den enskilda omsorgstagaren hamnar i gränssnittet mellan individen och organisationen. Avhandlingens syfte är att fördjupa kunskapen om relationen mellan funktionshindrade personer och kommunens organisation för samhällsskydd och beredskap gällande trygghet och säkerhet. Fyra separata empiriska delstudier från Sverige inkluderas. Den första undersöker kvantitativt vilka riskuppfattningar personer med funktionshinder har och om kan de förklaras av funktionshindret. Övriga tre delstudier är kvalitativa och studerar i tur och ordning: hur risk- och sårbarhetsfrågor manifesteras, erfars och hanteras av funktionshindrade; hur kommuner organiserar för samhällsskydd och beredskap på lokal nivå och vilken roll kommunen har på det lokala verksamhetsfältet för detta; hur en faktisk krisartad situation hanterades på olika nivåer av den kommunala vård- och omsorgen. De två studierna om funktionshindrade visade att tillit är central för hur riskuppfattningen formas och att den vardagsnära säkerheten är viktig. Personerna utvecklar strategier för att hantera sårbarhet genom att undvika vissa situationer, att visa eller dölja sina behov och att lära sig stå ut med att saker och ting tar lång tid. Detta formar ett interpretationsramverk för trygghet och säkerhet där kroppen speglas som objekt och social representation. Därmed kan kroppen likställas med andra sociala representationer och försvaras, riskförebyggas och skademinimeras. Den första kommunstudien visar att den lokala organiseringen av samhällsskydd och beredskap sker på liknande sätt över landet. Däremot har den kommunala funktionen för skydd och säkerhet att hantera olika organisatoriska relationer med distinkt skilda karaktärer. Relationen till den kommunala organisationen i stort är labyrintartad till följd av rationalitetsproblem inom ändamålsenlighet, mål, ansvarsförläggande och uppföljning är oklara eller helt enkelt saknas; relationen till de kommunala förvaltningarna präglas hierarkiproblem genom brist på auktoritet, legitimitet och exekutiv makt; relationen till externa aktörer uppvisar problem med identitet till följd av brist på resurser och tydlig organisation. Den andra kommunstudien visar att den tid-rumsliga inramningen av en störning i det kommunala dricksvattnet skilde sig åt mellan olika organisatoriska nivåer och att störningen hanterades genom en aktiv agens där tillit och handlingsutrymme var avgörande. Avhandlingens övergripande analys utifrån tillitsteori landar i att medan det tidigare systemet för samhällsskydd och beredskap präglades av en instrumentell tillit med vertikalt riktad makt och en problemlösningsförväntan, är dagens system mer beroende av en humanitär tillit med horisontell maktfördelning och med förväntan på att hantera sårbarhet. De tre teoretiska sårbarhetsformerna beroende, oförutsägbarhet och oåterkallelighet föreslås på den lokala samhällsnivån kunna reduceras med de tre tillitsmekanismerna autenticitet, legitimitet respektive transparens. Det är en typ av tillit som är bättre anpassad för det gränssnitt mellan den enskilda individen och organisationen där vi hittar mycket av ansvaret för trygghets- och säkerhetsfrågor idag.

  • 265.
    Stenström, Nils
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för socialt arbete.
    Sprutbyte vid Intravenöst Narkotikamissbruk: En longitudinell studie av deltagarna i sprutbytesprogrammet i Malmö2008Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    The aim of this thesis is to describe the users visiting the syringe exchange clinic in Malmö with respect to what characterises the group, how they utilize the services of the clinic and how their patterns of participation relate to risk behaviour, physical and mental health and social development. The heterogeneity of the group has been captured by the use of Stimsons dimensions “integration in majority society” and “involvement in sub-culture”, yielding four different groups of syringe exchangers: “stables”, “loners”, “two-worlders” and “junkies”. The study rests on two sources of data: a register from the clinic including all syringe exchangers that have visited the clinic between 1989 and 2003, altogether 3660 individuals, and an interview of visitors at the clinic during 1995, including 496 persons.

    The results show that syringe exchangers, compared to other persons with severe addiction in Malmö, to a larger extent use amphetamine as their drug-of-choice, are older and inject more irregularly. The population visiting the clinic is heterogeneous with respect to integration in society and involvement in sub-cultures. The group classified as junkies do, as expected, display the highest inclination to share syringes and needles with other and hence have the most advanced risk behaviours. As to utilization of the programme, the results show that the longer the syringe exchangers stay in the programme, the more frequent they visit it. Also with respect to utilization-patterns, we find substantial variations within the studied group. Five categories are discernible: drop-in visitors with only one or two visits, sporadic visitors who in spite of contacts over a number of years never really establish a regular contact, intermittent visitors who have had contact over several years but display a very irregular visiting pattern, regular visitors who relatively fast establish a consistent contact with visits between uniform time intervals and frequent visitors who tend to stay longer than others and visit the clinic more often. Another aspect of utilization is to what extent the distribution of needles and syringes cover the needs of the visitors. With a strict definition of need, only a minority manages to cover their needs, but if we accept a more extensive individual re-use, around 90 percent of the average need is covered. Data also reveals that a very high proportion of the users on at least one occasion have visited the programme without syringe exchange taking place or any complementary service delivered. Basically these visits seem to be of a more social nature, reinforcing the contacts between the staff and the visitors.

    Data do not give any clear support for the basic assumption that syringe exchange reduce the incidence of HIV or hepatitis. Recent sharing of utensils or low coverage of syringe need through the programme do not predict a higher infection risk. Instead we find that the social contacts with the staff (without syringe exchange) function as a predictor of lower incidence. This indicates that the mechanisms may be more complex than just related to the provision of clean needles and syringes. The result shows that integration increase over time while sub-cultural involvement decreases. However, the patterns for different groups are very diverse and we find no evidence that more frequent contacts as such are related to increased integration. There is however, some evidence that social visits are positively related to increased integration. No support could be found for the assumption that the programme increases the number of severe addicts.

  • 266.
    Strand, Susanne
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för hälsovetenskap.
    Violence risk assessment in male and female mentally disordered offenders: differences and similarities2006Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    When assessing the risk of violence, increasing interest has been shown in bringing science and practice closer together. Moving from clinical intuition in the first generation of risk assessment via actuarial scales in the second generation to the structured professional judgments where risk assessments are today produces better, more valid results when assessing the risk of violence. One of the best predictors of violence is gender. Approximately 10% of the violent criminality can be attributed to women; even so, it is increasing, especially among young women. It is therefore important to examine risk assessments from a gender perspective. Another important factor when assessing the risk of violence is psychopathy and there are indications that there might be gender differences in this diagnosis. Thus, a special interest has been focused on psychopathy in this thesis. The purpose with this work is to explore the similarities and differences in assessing risk for violence in male and female mentally disordered offenders, while the overall aim is to validate the violence risk assessment instrument HCR-20 for Swedish offender populations. The risk assessments for all six studies in this thesis were made by trained personnel using the HCR-20 instrument, where psychopathy was diagnosed with the screening version of the Psychopathy Checklist (PCL:SV). The study populations were both male and female mentally disordered offenders in either the correctional or the forensic setting.

    The findings show that both the validity and the reliability of the HCR-20 and the PCL:SV were good and the clinical and risk management subscales were found to have better predictive validity than the historical scale. Another finding was that there were more similarities than differences between genders in the HCR-20, while the opposite applied to the PCL:SV, where the antisocial behavior was performed in a different manner. Moreover, it was found that the gender of the assessor might be a factor to take into account when

    assessing the risk of violence in women, where the recommendation was that at least one assessor should be female. The conclusions were that the HCR-20 and the PCL:SV can be used In Swedish offender populations with valid results. For female offenders, there are differences in the antisocial behavior that is assessed in order to diagnose psychopathy and these differences tend to underestimate psychopathy among female offenders. Furthermore, the gender of the assessor might be of greater importance than has previously been realized. The overall conclusion was that this thesis supports the structural professional judgment method of making risk assessments in order to prevent violence in the community.

  • 267.
    Sundberg, Håkan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Problems in public e-service development2006Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis focuses on the general problem of integration and co-operation between business and IT organisations, and on the specific problem of co-ordinating the development process across stovepiped departments that do not collaborate cross-functionally. The purpose is to increase knowledge and understanding about public organisations’ difficulties in meeting their customers’ and the organisation’s needs for electronic services. The thesis also presents a model showing the relationships between factors of importance for understanding public organisations’ difficulties in implementing cross-functional or inter-departmental electronic services. The research is based on case studies of public and private organisations, and results show that public organisations attempting e-government will face large problems if they are unable to solve their internal stovepipe problems. On the other hand, they cannot expect the stovepipe problems to be solved without increasing customer orientation. Many private organisations have increased their speed in e-services, customer orientation and organisational changes, and have faced economic pressure early, while the public organisations are impeded by the role of law, complex goal structures, lack of collaboration and culture. But at the same time the public organisations are following a similar path to that of the private, and areas have been found where there are little differences (e.g. development processes and purchaser-contractor relationships). Furthermore, the thesis has identified a large potential in the use of enterprise architecture for improving co-operation between business and IT organisations and in the purchaser-contractor relations. An architecture is an important prerequisite for dealing with the growing complexity in describing an enterprise and its business, information, applications and technology.

  • 268.
    Sundberg, Leif
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationssystem och –teknologi.
    The Relation Between Digital Technology and Values: Thinking Through Multiple Technologies2019Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Denna avhandling studerar relationen mellan digital teknik, ofta benämnd ”digitalisering”, och värden. Materialet tar sin utgångspunkt i historiska och aktuella utredningar och policys framtagna inom svensk offentlig sektor. Syftet att fördjupa förståelsen för hur olika tekniksyner i dessa påverkar värden såsom professionalitet, effektivitet, service och demokrati. Studiens motivation är att teoretisera forskning om digital förvaltning, skapa en länk mellan historier om teknik, och aktuell forskning om värden, och att förstå hur investeringar i digital teknik legitimeras. Avhandlingen hämtar teoretiska utgångspunkter från teknikfilosofi, och forskning om värden inom offentlig sektor. Resultaten från fem artiklar sammanfattades genom narrativ analys, och renderade följande slutsatser: relationen mellan teknik och värden kan förstås..:

     -Som en konvergens, där digital teknik assimilerat äldre tekniker. Två berättelser framträder i denna kontext: det flexibla verktyget, och den autonoma maskinen. Konvergens möjliggör realisering av flera värden med hjälp av tekniken, samtidigt som det ofta sker genom standardisering och uniformitet. Berättelsen om maskinen blir dominant eftersom den kommer med uppmaningar om att samhället och individen måste anpassas. I offentlig förvaltning innebär denna anpassning en transformation av professionella värden. Denna transformations legitimitet är i hög grad beroende på vilken tekniksyn den baseras på, då en autonom teknik påverkar värden som till exempel ansvarighet.

     -Som ett paradigm, där manifesteringen av värden påverkas av normerna inom detta paradigm. Det digitala paradigmet i det studerade materialet, är karaktäriserat av en berättelse om ett teknologiskt samhälle för alla. Denna berättelse berättas dock av aktörer från en smal kontext vad gäller utbildningsbakgrund och geografisk hemvist. I och med att direktiv om digital förvaltning ofta har som mål att bredda användningen av digital teknik, borde en förutsättning för denna bredd vara att bredda normerna som beskriver det digitala samhället.

     -I termer av kongruens och divergens. Relationen mellan digital teknik och värden skiftar mellan värdekongruens, och värdedivergens. Samspelet mellan dessa berättelser påverkar hur realisering av värden uppfattas. Berättelsen om ett epokskifte karaktäriserat av teknologiska och ekonomiska framsteg tenderar att generera en syn på tekniken som något autonomt, vars värde ligger i framtiden. Nutiden är alltid transformativ. Denna berättelse står i kontrast mot utvärderingar från praktiken, där värden divergerar. Divergensen positioneras som en berättelse om ”hinder” för fortsatt utveckling.

    Avhandlingen konkluderas med att föreslå en breddning av de normer som informerar politik och beslutsfattare. Om dessa beslutsfattare aktivt skulle behöva navigera och välja mellan inkommensurabla tekniksyner skulle det ha positiva konsekvenser för legitimitet, ansvarighet och transparens.

  • 269.
    Sundqvist, Anneli
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Search Processes, User Behaviour and Archival Representational Systems2009Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Information technology and political motives, e.g. e-governance, freedom of information legislation, has recent years lead to an increasing emphasis on users and access to records, but little research based knowledge about those issues exist so far. The main focus of the previous research is the use of non-current records in archival repositories. The aim of this thesis is to make a contribution to the research field, in order to gain a better understanding of the information behaviour of users of records in contemporary organizational settings. The research questions addressed are:

    § How are records used in contemporary organizations?- In what context and for what purposes are records used?- What user categories can be identified?

    § How is the search for records mediated?- What intermediaries are used in the search process?- How well do the features of the artefactual intermediaries serve the users' information needs?- What is the role of human intermediaries?

    An additional purpose of the study is to contribute to theory development, and to provide a conceptual model of the information behaviour of users of records that can form the basis for further research.

    The thesis is based on explorative case studies undertaken in two contemporary Swedish public organizations, one municipality and one governmental agency. Data was collected through interviews, analysis of documentary sources and complementary observations. The analysis of the findings was guided by a theoretical framework consisting of activity theory informed by concepts from archival theory and models of information behaviour.

    The results of the cases studies showed that information behaviour of users of records and the search process could be described as a part of an activity system. The search process was a sub-ordinated activity of other activities. The needs for records was generated by a task or accomplishment of anykind with purpose to achieve something. Those needs motivated the purposes of use of records: material, operational, accountability seeking or knowledge enhancing purposes. The subjects, users in collaboration with the registrars and archivists, seeked to obtain records with help of different mediational means, e.g. artifactual intermediaries as the journal and the archives inventory that could be defined as representational systems, in order to reach a certain outcome: fact-finding, re-construction of past actions and events, regaining experience and knowledge, verifying status, or illustrating and exemplifying.

    A variety of user groups, internal as well as external, could be identified in both organizations. Those could act as direct or indirect users, and indirect use by one part meant direct use by another who acted as a mediator between the records and the end users. The external users could be defined as stakeholders of the organizations or other users. Users showed, with occasional exceptions, a preference for informal means of mediation, particularly personal communication.

    Certain features of the formal representational systems, journals and inventories, could be identified, which made them less useful as search tool. Those were generated by contradictions and tensions within the organizations: contradictions within the representational systems; contradictions between the tasks of the users and the representational systems; contradictions between user requests and the access points in the representational systems; contradictions between external users and the activities of the organizations; contradictions between exogenous institutional conditions and the the activities of the organizations; and contradictions of a temporal character. These circumstances necessitated an active intervention of human intermediaries. This could be seen as an example of the division of labour in the organizations. Search and retrieval of records were part of the registrars’ and the archivists’ specific professional knowledge, but were not considered as primary tasks of other employees or, especially not, of the external users.

    The results of the study contributes to to the knowledge about the use of records, and how records are approached. It provides a model of the search process that can form the basis for further research. The practical implications of the findings could be improved search tools and user services, i.e. enhanced access. The thesis can also contribute to theoretical enrichment of the field by combining a more comprehensive social theory with archival theory and concepts from information science.

     

  • 270.
    Sundström, David
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kvalitetsteknik, maskinteknik och matematik.
    Numerical optimization of pacing strategies in locomotive endurance sports2016Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Avhandlingen handlar om optimering av farthållningsstrategier inom längdskidåkning och landsvägscykling. Det finns ett utbrett stöd för att konstant fart och varierande effektfördelningar är optimala om endast mekaniska aspekter beaktas i dessa sporter. Ändå saknas teoretiska studier som undersöker optimal farthållning för verkliga idrottsutövare som är begränsade i sin förmåga att generera effekt genom kroppens bioenergetiska system.

    Målen med den här avhandlingen är att utveckla metoder för bioenergetik och optimering av farthållningsstrategier i uthållighetsidrott. Dessutom är målet att undersöka påverkan av backar, svängar, omgivande vind och bioenergetisk modellering på den optimala farthållningsstrategin samt att utreda potentialen till prestationsförbättring med optimala farthållningsstrategier.

    Avhandling presenterar matematiska modeller för optimering av farthållningsstrategier. Dessa modeller delas in i en mekanisk modell för förflyttning, en bioenergetisk modell och en optimeringsmodell. De mekaniska och bioenergetiska modellerna som presenteras i avhandlingen består av differentialekvation och optimeringsmodellen utgörs av en gradient-baserad algoritm. Den mekaniska modellen beskriver förhållandet mellan utövarens effekt och den resulterande rörelsen längs banan som ger tiden mellan start och mål. Den bioenergetiska modellen beskriver människokroppens olika energisystem och dess begränsningar att generera effekt. Den bioenergetiska modellen interagerar med optimeringsmodellen genom att utgöra dess begränsningar för vad den mänskliga kroppen klarar av. Sammanfattningsvis försöker optimeringsmodellen minimera tiden mellan start och mål i den mekaniska modellen genom att variera effekten längs banan. Samtidigt ser optimeringsmetoden till att denna effektfördelning inte kränker den bioenergetiska modellen.

    Studierna som ingår i avhandlingen resulterade i flera viktiga upptäckter om generella tillämpningar av farthållningsstrategier inom längdskidåkning och landsvägscykling. Det visade sig att konstant fart inte är optimalt om omgivande betingelser varierade längs banans sträckning. Däremot var varierande effektfördelning fördelaktig om den varierar parallellt med banlutning och omgivande vindpåverkan för att minska fartens variationer. Trots denna variation, visade resultaten att fartvariationerna inte eliminerades helt. Detta har att göra med utövarens fysiologiska begränsningar, vars påverkan är svår att förutspå utan genomgående modellering av bioenergetik relaterat till muskeltrötthet. Dessutom viii

    visade resultaten att olika bioenergetiska metoder gav upphov till betydande skillnader i de optimala farthållningsstrategierna.

    Resultaten i avhandlingen visade också att optimal effektfördelning vid kurvtagning i landsvägscykling innehåller tre eller fyra faser. The fyra faser som var utmärkande på relativt långa banor var en tröskelfas, en rullfas, en bromsfas och en maximal accelerationsfas. Resultaten visar också att positiv farthållning är optimal på relativt långa banor i landsvägscykling där tillgången på kolhydrater är begränsad. Samtidigt visade resultaten på optimala farthållningsstrategier ibland att inverkan av omgivande betingelser förbisågs till fördel för med inflytelserika betingelser som påverkar framdrivningen.

    Sammantaget visar resultaten i denna avhandling att utövare gagnas av att anpassa effekten med hänsyn till varierande terräng, omgivande vind, atletens egen fysiologiska och biomekaniska förmåga, banans längd och hinder såsom kurvor. Resultaten visar också att de optimala farthållningsstrategier med varierande effektfördelning som beräknats i denna avhandling förbättrar prestationen jämfört med konstanta effektfördelningar. Sammanfattningsvis visar denna avhandling på möjligheterna att använda numerisk simulering och optimering för att optimera farthållningsstrategier i längdskidåkning och landsvägscykling.

  • 271.
    Svanedal, Ida
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Fundamental Characterization and Technical Aspects of a Chelating Surfactant2014Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The purpose of this study was to investigate the fundamental characteristics of a chelating surfactant in terms of solution behaviour, chelation of divalent metal ions, and interaction in mixtures with different foaming agents and divalent metal ion, as well as examining its prospects in some practical applications. Chelating surfactants are functional molecules, with both surface active and chelating properties, which are water soluble and therefore suitable for chelation in many aqueous environments. The dual functionality offers the possibility to recover the chelating surfactant as well as the metals.

    The DTPA (diethylenetriaminepentaacetic acid)-based chelating surfactant 4-C12-DTPA (2-dodecyldiethylenetriaminepentaacetic acid) was synthesized at Mid Sweden University. In the absence of metal ions, all eight donor atoms in the headgroup of 4-C12-DTPA are titrating and the headgroup charge can be tuned from +3 to -5 by altering the pH. The solution properties, studied by surface tension measurements and NMR diffusometry, were consequently found strongly pH dependent. pH measurements of chelating surfactant solutions as a function of concentration was used to extract information regarding the interaction between surfactants in the aggregation process.

    Small differences in the conditional stability constants (log K) between coordination complexes of DTPA and 4-C12-DTPA, determined by competition measurements utilizing electrospray ionization mass spectrometry (ESI-MS), indicated that the hydrocarbon tail only affected the chelating ability of the headgroup to a limited extent. This was further confirmed in hydrogen peroxide bleaching of thermomechanical pulp (TMP) treated with 4-C12-DTPA.

    Interaction parameters for mixed systems of 4-C12-DTPA and different foaming agents were calculated following the approach of Rubingh’s regular solution theory. The mixtures were also examined with addition of divalent metal ions in equimolar ratio to the chelating surfactant. Strong correlation was found between the interaction parameter and the phase transfer efficiency of Ni2+ ions during flotations. Furthermore, a significant difference in log K between different metal complexes with 4-C12-DTPA enabled selective recovery of the metal ion with the highest log K.

    The findings in this study contribute to the understanding of the fundamental characteristics of chelating surfactants, which can be further utilized in practical applications.

  • 272.
    Svedin, Glenn
    Mittuniversitetet, Fakulteten för humanvetenskap, Avdelningen för humaniora.
    "En ohyra på samhällskroppen": Kriminalitet, kontroll och modernisering i Sverige och Sundsvallsdistriktet under 1800- och det tidiga 1900-talet2015Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This thesis presents an analysis of crime trends and social control during the dramatic transformation of Sweden's social landscape in the nineteenth and early twentieth centuries, set against the background of the modernization process in the country as a whole and the city of Sundsvall and environs in particular. What assumptions about crime were evident in public debate? How did crime levels vary from region to region, and what were the changes over time? What strategies did government and local authorities try for combating crime? Did the joint efforts by government, local communities, and the voluntary sector actually solve the problems that social change was believed to have caused?When it comes to theory, the interpretative framework is based on Anthony Giddens's argument about modernity and modernization, making particular use of a few central points about what the changes meant for the structuration of society. Giddens's ideas about changes in social control are refined with Michel Foucault's and David Garland's work on the increasingly disciplinary trend seen in the exercise of the law and public control. The analysis of modernity's ramifications for the transformation of both social structures and crime alike has also benefitted from Robert Putnam's and Travis Hirschi's insights into the importance of social capital and social bonds for a well-functioning, low-crime society.The process by which Sweden was transformed from an overwhelmingly agrarian country to an urban, industrial society left its mark on crime patterns. To the contemporary mind, industrialization, migration, and urbanization were the underlying causes of the high levels of serious crime in the society. The start of the nineteenth century had seen a rise in criminality, with both petty crime and lethal violence becoming more common. At the same time, there was a heated debate about the socio-economic problems that were such a strain on the structure of society. The analysis finds that there were large differences in prosecutions in the country and between cities. The Sundsvall area was among those that saw a dramatic change in crime in the course of becoming a major industrial region. At the same time, the thesis shows that there were plenty of cities in Sweden, however rapidly they grew, that had low crime rates. However, the widespread fear of industrialization, migration, and urbanization was often unfounded. For example, both lethal violence and public order offences reached their lowest recorded levels in the interwar period. By then, new cures were sought for the social and moral ills of society. The state's sphere of influence had expanded. New social reforms, including a modified crime policy, were launched. The state became even more assertive, and the same was true of civil society. Society would attend to the moral education of a number of different groups. Moral virtues were to be instilled in the workshy, alcoholic, or criminal, in order to produce disciplined and cultured citizens. The attention of social activists, the scientific community, civil servants, and local and national politicians shifted from crime per se to the far broader issue of asociality. Modernization gave the voluntary sector a significant role in the social organization of the day, shaping new forums for interpersonal relationships and strengthening social ties. The thesis makes the case that two distinct periods, each with its specific social structures and crime patterns, can be observed; one belonging to the nineteenth century, the other to the first four decades of the twentieth century.Finally, the similarities between the history of crime in Sweden and, for example, the US or the UK are highlighted. As in Britain and North America, the early industrialization period saw weakened social bonds, and a time of greater violence and disorder ensued. After a while however, the situation stabilized, and crime rates began to drop again. When industrial societies ceased to be 'frontier communities' at the forefront of modernization, and instead became more mature communities, crime levels fell as people's commitment to their communities was renewed.

  • 273.
    Svensson, Birgitta
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Frictional studies and high strain rate testing of wood under refining conditions2007Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    When producing thermomechanical pulps (TMP), wood chips and fiber material are loaded mechanically in a disc-refiner to separate the fibers and to make them flexible. In the process, much of the energy supplied is transferred to the fiber material through cyclic compression, shear and friction processes. Therefore, compression and friction characteristics are needed in order to gain a better grasp of the forces acting during refining. To this end, in this thesis, the compressive and frictional behaviors of wood were investigated under simulated chip refining conditions (i.e., hot saturated steam, high strain rate compression, and high sliding speed). Two new, custom-designed, experimental setups were developed and used. The equipment used for compression testing was based on the split Hopkinson pressure bar (SHPB) technique and the friction tester was a pin-on-disc type of tribotester (wear rig). Both pieces of equipment allow a testing environment of hot saturated steam.

     

    In the wood–steel friction investigation, the influence of the steam temperature (100-170°C) was of primary interest. The wood species chosen for the friction tests were spruce (Picea abies), pine (Pinus sylvestris, Pinus radiata), and birch (Betula verrucosa). When performing measurements in the lower-temperature region (100-130°C), the friction coefficients registered for the softwoods were generally low and surface properties such as lubrica­tion were suggested to have a great influence on the results; however, in the higher-tempera­ture region (~130 -170°C), the friction coefficients of all investigated wood species were probably determined by bulk properties to a much greater extent. When most of the wood extractives had been removed from the specimens, testing results revealed distinct peaks in friction at similar temperatures, as the internal friction of the different wood species are known to have their maxima at ~110–130°C. One suggested explanation of these friction peaks is that reduced lubrication enabled energy to dissipate into the bulk material, causing particularly high friction at the temperature at which internal damping of the material was greatest. During the friction measurements in the higher-temperature region, the specimens of the different wood species also started to lose fibers (i.e., produce wear debris) at different characteristic temperatures, as indicated by peaks in the coefficient of friction. In refining, the generally lower shives content of pine TMP than of spruce TMP could partly be explained by a lower wear initiation temperature in the pine species.

     

    Wood stiffness is known to decrease with temperature, when measured at low strain rates. The results presented in this thesis can confirm a similar behavior for high strain rate compression. The compressive strain registered during impulsive loading (using a modified split Hopkinson equipment) increased with temperature; because strain rate also increased with temperature. Accordingly, the strain rates should determine the strain magnitudes also in a refiner, since the impulsive loads in a refiner are of similar type. Larger strains would thus be achieved when refining at high temperatures. The results achieved in the compression tests were also considered in relation to refining parameters such as plate clearance and refining intensity, parameters that could be discussed in light of the stress–strain relations derived from the high strain rate measurements. Trials recorded using high-speed photography demonstrated that the wood relaxation was very small in the investigated time frame ~6 ms. As well, in TMP refining the wood material has little time to relax, i.e., ~0.04–0.5 ms in a large single disc refiner. The results presented here are therefore more suitable for comparison with the impulsive loads arising in a refiner than are the results of any earlier study. It can therefore be concluded that the modified SHPB testing technique combined with high-speed photography is well suited for studying the dynamic behavior of wood under conditions like those prevalent in a TMP system.

  • 274.
    Svensson, Fredrik
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för samhällsvetenskap.
    Essays on entrepreneurship and bureaucracy2008Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The overall aim of this thesis is to explore the theoretical and empirical relationship between entrepreneurship and bureaucracy, and to examine the cause and effect of entrepreneurship. From this overall aim, four specific questions are investigated.

    The first question deals with the issue of combining agency and structural explanations of entrepreneurship. Traditional one-sided explanations are discussed, and a two-sided explanatory model of the entrepreneurial choice is presented and tested empirically. In relation to this, the issue of causal heterogeneity is discussed and tested. The empirical results indicate that several country-level variables, including bureaucracy, influence the entrepreneurial choice at the individual level, and that the effect of some individual variables on the entrepreneurial choice varies according to structural context. The following two questions deal with the relationship between the entrepreneur and bureaucracy. The first one describes how the entrepreneurial process is regulated by bureaucracy, and how entrepreneurs solve regulatory problems. From this study it is clear that the smaller entrepreneurs comply with 'good' law in order to enjoy the benefits of formality, and avoid 'bad' law to reduce the costs of formality.

    The larger entrepreneurs comply with all regulations and are very frustrated over delays and inefficiency. The smaller entrepreneurs have a more understanding attitude towards bureaucratic inefficiency and have less trouble solving regulative problems. Both groups have strategies for solving regulative problems; most frequently this involves social ties with public officials and bribes. The second of the relationship questions investigates the extent to which entrepreneurs are obstructed by or dissatisfied with the regulatory authorities, and whether this varies over different types of entrepreneurs. Based on Schumpeter’s distinction between entrepreneurs and other, less creative, business owners, the overall results indicate that creative companies have larger problems with regulatory authorities.

    The conclusion is that bureaucracy tends to be a problem with regard to new ideas, but not for new companies. The fourth question raised deals with the economic effects of entrepreneurship and bureaucracy. Can entrepreneurship and bureaucracy explain variation in economic development across countries? The results indicate that entrepreneurship combined with bureaucracy offer high explanatory values and that a large part of the variance in economic development, left unexplained by agency behaviour, is explained by the regulation of that behaviour. In terms of policy implications the results indicate that the removal of bureaucratic barriers to entrepreneurs could have large potential payoffs in terms of economic growth.

  • 275.
    Svensson, Jessika
    Mittuniversitetet, Fakulteten för humanvetenskap, Avdelningen för hälsovetenskap.
    Gambling and gender: A public health perspective2013Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Prevalence studies around the world show that men are the largest group at risk of becoming problem gamblers and that men gamble more than women. However, gambling research has long been gender blind. The gambling market is rapidly changing, with the Internet making gambling more accessible. Further, despite the well-documented presence of health, social and financial problems among the concerned significant others (CSOs) of someone close with gambling problems in clinical and help-seeking samples, there is little research investigating on this population. This thesis aims to examine the relation between gender and problem gambling among regular gamblers and CSOs, and to determine whether there was a convergence of men’s and women’s gambling behavior between 1997/98 and 2009/10 in Sweden. A further aim is to examine health problems associated with Internet gambling and CSOs.

    The data collections were taken from three different but linked gambling and health representative national population based studies in Sweden, all using the same methods: telephone interviews supplemented by questionnaires. The studies are as follows: 1) prevalence study 1997/98, age 15-74 years, n = 10,000, response rate 72% (n = 7,139) 2) prevalence study 2008/09, age 16-84 years, n = 15,000, response rate 63% (n = 8,165); and 3) incident study 2009/10, the 8,165 participants from the 2008/09 prevalence study were contacted again, response rate 74% (n = 6,021).

    Gambling was generally merged into domains based on the axis chance-strategy and public-domestic. The dichotomy of public and private spheres is relevant in since there is a link between the public sphere and notions of masculinity and a link between the private and femininity. Further, the literature suggests that men are attracted to gambling that involves features of strategy, whereas women generally prefer game of chance. Problem gambling was measured using SOGS-R and PGSI. Health variables included measures such as self-reported health, psychological stress, social support, alcohol consumption, and financial situation as a determinant of health.

    There were very few indications of a convergence between men’s and women’s gambling behavior. Men and women generally gambled in different domains. Men gambled more than women and dominated all domains except the domain of chance-domestic, a domain associated with less risk and Internet gambling. However, men and women who gambled regularly were just as likely to be problem gamblers. No gender differences were found in the score from separate PGSI analyses in the chance-public domain (games of chance in public spaces, such as gambling machines and bingo in halls). This domain was also the only domain associated with problem gambling for women who gambled regularly. Men and women were just as likely to report that they were CSOs and they constituted a large proportion of the Swedish population (18%). CSOs experienced a range of social, economic and health related problems including psychological stress, risky alcohol consumption, exposure to violence, and separations. For women who were CSOs, no relation with own problem gambling was found.

    This thesis suggests that the presence of gambling machines must be addressed to prevent problem gambling and that separate analyses for men and women are required to identify important differences between genders. The findings indicate that gambling domains produce and reinforce gender. Further, to be able to prevent problem gambling we require further knowledge about these gendered processes. However, it is also important to see the overall similarities between men and women to avoid reinforcing stereotypical images of gender which would have an negative impact on the preventive work. Male and female gamblers are both very heterogeneous categories where the specific gambling site, context and life circumstances must be acknowledged.

    Prevention, research and interventions should also target CSOs if a public health approach is applied because they require help and support in their own right. CSOs also play an important to the problem gambler. More qualitative research is required to understand gendered processes in gambling, as well as further research on interventions that go beyond the individual and address gambling and problem gambling at various levels. When addressing the harmful effects of gambling from a public health perspective, it is imperative to recognize the ethical principles of justice, autonomy, doing no harm and beneficence.

  • 276.
    Svensson, Sven
    Mittuniversitetet, Fakulteten för humanvetenskap, Avdelningen för samhällsvetenskap.
    Delad tillit: Studier av personalinhyrning2015Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Under 1980-talet började det på olika sätt att talas om ett nytt arbetsliv karakteriserat av organisationers ökade behov av flexibilitet. Under 1990-talet kulminerade denna diskurs med teorier om gränslösa anställningar. Dessa beskrivningar och teorier har visat sig vara kraftigt överdrivna. En liten grupp på arbetsmarknaden, personal som hyrs in av ett kundföretag från bemannings- eller konsultföretag, förkroppsligar dock denna idé om gränslösa anställningar. Bakom idén om det gränslösa arbetslivet ligger ett ideal om fria och autonoma arbetstagare som slitit sig fria från vad som beskrivs som den traditionella anställningens bojor och organisationstillhörighetens ok. Samtidigt konstateras att personal som inte tillhör den organisation där de arbetar blir svåra att reglera och kontrollera. Managementforskningen har identifierat problemen och har föreslagit att tillit på olika sätt ska användas som en kontrollmekanism.

    I föreliggande avhandling konstateras det att organisationers koordineringsproblematik blir till krav som den inhyrda personalen måste hantera. Det konstateras hur inhyrd personal möter krav på personlig kontroll, förmåga till social anpassning i skiftande organisationer och krav på ett personligt ansvar för sin kompetensutveckling. Tidigare forskning har visat hur dessa krav förenas med en arbetssituation som kan göra det svårt att leva upp till dem. Med utgångspunkt i sociologisk tillitsteori kan det antas att en oförmåga att leva upp till sådana krav ger en låg grad av kontroll. Kontroll är i sin tur relaterat till tillit. Den sammantagna bilden tycks alltså ge vid handen att arbetet som inhyrd förutsätter tillit, samtidigt som anställningsformen i viss mån underminerar förutsättningarna för tillit. I avhandlingens empiriska delstudier analyseras den inhyrda personalens möte med de krav som de möter i sitt arbete. Olika aspekter av arbete, relaterat till tillit, analyseras.

    I den första delstudien analyseras det så kallade psykologiska kontrakt som inhyrd personal har med den kundorganisation där de arbetar. Det konstateras att kontraktet består av två dimensioner med inriktning på kompetensutveckling respektive socialt utbyte med kollegor i kundorganisationerna. Det konstateras även att gemenskapsdimensionen av kontraktet inte revideras i någon större utsträckning med arbetad tid i kundorganisationen men att uppfattade löften om kompetensutveckling i arbetet i någon mån avtar med tid i kundorganisationen.

    I den andra delstudien prövas ett antagande om att ett arbete som avviker från den traditionella tillsvidareanställningen (standardanställning) kan förväntas vara relaterad till tillit till andra människor i allmänhet (s.k. generalized trust). Resultaten ger stöd för antagandet. Arbetstagare med så kallat non-standard anställningar i allmänhet - och inhyrd personal specifikt - har en lägre sannolikhet att hysa tillit till människor i allmänhet. Resultaten kan delvis förklaras av en försvagad självtillit i gruppen non-standard.

    I avhandlingens tredje delstudie jämförs inhyrd personal med standardanställd personal avseende tillit till kollegor. Med utgångspunkt i tidigare forskning prövas ett teoretiskt antagande om att den inhyrda personalen i mindre utsträckning uppfattar normer i kundorganisationen som kollektivt delade och att de i jämförelse med standardanställda kollegor inte uppfattar sig få lika mycket kompetensutveckling i arbetet. Det kan inte konstateras någon skillnad i upplevd tillgång till kompetensutveckling i arbetet mellan de respektive personalkategorierna inhyrd och direktanställd standardpersonal. Tvärt emot formulerade antaganden visar resultaten att den inhyrda personalen i större utsträckning än den direktanställda standardpersonalen uppfattar normer som kollektivt delade i kundorganisationen. För kompetensutveckling kan det inte konstateras någon skillnad. Detta beaktat visar resultaten ändå att den inhyrda personalen har en lägre sannolikhet att hysa stark tillit till sina kollegor.

    I den fjärde delstudien analyseras betydelsen av att uppfatta sig som frivilligt engagerad i arbetet som inhyrd och betydelsen av att uppleva sig få kompetensutveckling i arbetet (employability development) för tillit till den inhyrande organisationen. Resultaten visar att personal som uppfattar sig som ofrivilligt inhyrd har en lägre tillit till kundorganisationen. En interaktion mellan ofrivillighet och kompetensutveckling visar att kompetensutveckling är positivt relaterad till tillit till kundorganisationen för gruppen ofrivilligt inhyrda. Sambandet mellan kompetensutveckling och tillit till kundorganisationen är inte signifikant för de som uppfattar sig som frivilligt inhyrda.

    I den sammanfattande kappan lyfts artiklarnas resultat till en diskussion om personalinhyrning som en form av arbetsdelning, och relationen mellan arbetsdelning och tillit. Diskussionen förs med utgångspunkt i Durkheims begreppspar anomisk och tvingad arbetsdelning. Durkheims teori om arbetsdelning på samhällsnivå tas med Williamsons transaktionskostnadsteori ned till organisationsnivå. Med teorin om det psykologiska kontraktet diskuteras betydelsen av att få det som förväntas i transaktioner och betydelsen av att reglera innehållet i transaktioner mellan kontraktsparter. Den sammantagna slutsatsen är att den inhyrda personalens förutsättningar att utveckla tillit står i relation till sådana resurser som ges i arbete i kundorganisationer. Det argumenteras därför slutligt för att personalinhyrning är en form av arbetsdelning som ger upphov till en uppdelning i kategorier av människor som ges olika förutsättningar att utveckla tillit, något som slutligt uttrycks som ett teoretiskt antagande om att personalinhyrning leder till en uppdelning av människor i kategorier med olika nivåer av tillit beroende på deras position i arbetsdelningen.

  • 277.
    Thiagarajan, Kannan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för elektronikkonstruktion.
    Monte Carlo simulation of electron transport in semiconducting zigzag carbon nanotubes2013Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Since the advent of nanoscale material based electronic devices, there has been a considerable interest in exploring carbon nanotubes from fundamental science and technological perspectives. In carbon nanotubes, the atoms form a cylindrical structure with a diameter of the order 1nm. The length of the nanotubes can extend up to several hundred micrometers. Carbon nanotubes exhibit a variety of intriguing electronic properties such as semiconducting and metallic behaviour, due to the quantum confinement of the electrons in the circumferential direction. Much of the study dedicated to describe the behaviour of carbon nanotube-based devices assumes for simplicity the nanotube to be a ballistic material. However, in reality the phonon scattering mechanism exists also in nanotubes, of course, and can generally not be neglected, except in very short nanotubes. In this work, we focus attention on exploring the steady-state electron transport properties of semiconducting single-walled carbon nanotubes, including both phonon scattering and defect (vacancy) scattering, using the semi-classical bulk single electron Monte Carlo method.

     

    The electron energy dispersion relations are obtained by applying the zone folding technique to the dispersion relations of graphene, which are calculated using the tight-binding description. The vibrational modes in the carbon nanotubes are studied using a fourth nearest-neighbour force constant model. Both the electron-phonon and the electron-defect interactions are formulated within the tight-binding framework, and their corresponding scattering rates are computed and analyzed. In particular, the dependence of the phonon scattering rate and the defect scattering rate on the diameter of the nanotube, on temperature and on electron energy is studied. It is shown that the differences observed in the scattering rate between different nanotubes mainly stem from the differences in their band structure.

     

    A bulk single electron Monte Carlo simulator was developed to study the electron transport in semiconducting zigzag carbon nanotubes. As a first step, we included only electron-phonon scattering, neglecting all other possible scattering mechanisms. With this scattering mechanism, the steady-state drift velocity and the mobility for the nanotubes (8,0), (10,0), (11,0), (13,0) and (25,0) were calculated as functions of the electric-field strength and lattice temperature, and the results are presented and analysed here. The dependence of the mobility on the lattice temperature can be clearly seen at low electric-field strengths. At such electric-field strengths, the scattering is almost entirely due to acoustic phonons, whereas at high electric-field strengths optical phonon emission processes dominate. It is shown that the saturation of the steady-state drift velocity at high electric-field strengths is due to the emission of high-energy optical phonons. The results indicate the presence of Negative differential resistance for some of the nanotubes considered in this work. The discrepancy found in the literature concerning the physical reason for the appearance of negative differential resistance is clarified, and a new explanation is proposed. It is also observed that the backward scattering is dominant over the forward scattering at high electric-field strengths.

                                                                                     

    We then included also defect scattering, actually electron-vacancy scattering, for the nanotubes (10,0) and (13,0). The steady-state drift velocities for these nanotubes are calculated as functions of the density of vacancies, electric-field strength and the lattice temperature, using three different vacancy concentrations. The results indicate the presence of Negative differential resistance at very low concentration of defects, and how this feature may depend on the concentration of defects. The dependence of the steady-state drift velocity on the concentration of defect and the lattice temperature is discussed. The electron distribution functions for different temperatures and electric field strengths are also calculated and investigated for all the semiconducting nanotubes considered here. In particular, a steep barrier found in the electron distribution function is attributed to the emission of high energy optical phonons.

  • 278.
    Thomtén, Johanna
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för samhällsvetenskap.
    Pain among women: Prospective population studies from a biopsychosocial perspective on pain2012Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis focuses on the role of different psychosocial factors in the course of pain over time in a general population sample of women in Sweden. The main aim was to identify and quantify such factors as predictors of pain, pain-related disability and quality of life within a biopsychosocial framework for the understanding of the pain experience over time.  The studies were based on baseline (BL) and follow-up (FU) measures with 12 months apart among 2,300 women living in Sweden, and included physical and psychological health and socio-economic status.

    Study I investigated associations between socio-economic status (SES) at baseline and pain and pain-related disability at follow-up, and additionally a possible mediating role of depressive symptoms in such associations. The results indicated that educational level, financial strain and occupational level were associated with pain over time. Symptoms of depression were related to all pain-and SES factors, and might be understood as a mediating factor within this context. The results of Study II showed a link between symptoms of burnout at baseline and several pain-locations. Additionally, among women with pain, the characteristics of the pain experience and pain-related disability were associated with level of burnout over time. Study III focused on the sub sample of women reporting pain at follow-up, and examined possible predictors of their perceptions of quality of life (QOL). Several psychosocial factors were associated with QOL, and seemed to be more important predictors than the characteristics of pain in terms of intensity and frequency. These factors were burnout, emotional distress, and social support. Study IV was an attempt to sum up the results of the previous studies by analysing predictors of the course of pain, i.e. by comparing women that developed pain from BL to FU with those that remained pain-free and to compare women with sustained pain with those who recovered from pain during the assessment period. These analyses showed symptoms of posttraumatic stress (PTSD) to be associated with reporting emerging pain, while pain variables, educational level and social support were related to sustained pain.

    The results of the four studies in this thesis indicate that psychosocial factors and their interplay with the characteristics of pain can be identified and described in a female sample, with a broad definition of pain, and that these factors play a central role in the experience of pain and its impact on the everyday life of these women. There may be several possible paths leading to the development of persistent pain among women and the identification of risk factors is complicated by never-ending interactions between biological, psychological and social processes. At an early stage, prior to pain development, several risk factors may cluster together (e.g. SES, depression), and work as indicators of, e.g. dysfunctional coping in relation to pain. In the first contact with health care and among primary care personnel the identification of such indicators is crucial so as to find women at risk for prolonged pain conditions. General indicators might then be more easily distinguishable than certain individual behaviour characteristics widely accepted as risk factors for pain and disability (e.g. fear-avoidance). To spread the knowledge of general factors in the first line of health care is therefore of great importance in preventive work.

    Finally, the results demonstrated that many women report pain with characteristics that to a great extent affect their lives and through interactions with psychological and social health might have grave consequences for perceptions of quality of life.

     

  • 279.
    Thörnberg, Benny
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Memory modeling and synthesis for real-time video processing systems2006Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    I denna avhandling presenteras en ny metod och nya verktyg för modellering och syntes av videobearbetande system i realtid. Ett videobearbetande system är ett system som utför beräkningar på en kontinuerlig ström av bilder. Bildbehandling är en minnesintensiv applikation. Detta i sin tur leder till en stor utmaning för konstruktören, nämligen att överbrygga en välkänd skillnad i hastighet mellan minnen och beräkningsenheter. Det finns ett flertal välkända tekniker att övervinna denna skillnad genom att utnyttja lokaliteten och återanvändningen av data. Stöd från befintliga verktyg som kan hjälpa konstruktören med dataflödesanalys och minneskonstruktion kan dock anses vara blygsam. Genom att tillföra mekanismer för modellering av elektroniska system, så kan traditionella sekventiella programmeringsspråk, så som C/C++ användas för modellering av system. Ocapi och SystemC är två objektorienterade specifikationsmetoder som jämförts i en fallstudie. I denna studie framstår SystemC som bäst lämpad för specifikation av videobearbetande system. De flesta bildbehandlingsoperationer arbetar på en lokal mängd av bildpunkter. För en bildbehandlingskonstruktör så framstår denna lokala mängd av bildpunkter som en abstraktion. Tillika representerar samma mängd bildpunkter de databeroenden som är avgörande vid syntes. I denna avhandling presenteras IMEM, en ny specifikationsmetod som kan användas till att modellera minnesanvänding och transaktioner genom att utnyttja en lokal mängd bildpunkter. Två betydelsefulla steg mot att med automatik kunna översätta en modell i IMEM till en implementation i en Field Programmable Gate Array (FPGA) beskrivs. Dessa två problemformuleringar är delsteg i hela syntesprocessen. I första steget optimeras placering och storlek av alla buffertminnen. Hänsyn tas härvid till bitbredd, pipelining och eventuell delning av buffertar mellan flera databeroenden. I det andra steget allokeras buffertminnen till en mängd små dubbelportade minnen. Båda syntesstegen modelleras formellt med hjälp av nätverksflöden och linjär programmering. Dessutom presenteras en syntesmetod som kan översätta en enkel IMEMmodell till en implementation i en mediaprocessor. Cache-minneshantering och schemaläggning av instruktioner optimeras av verktyget. IMEM är en applikationsspecifik metod för videosystem som tillhandahåller en enkel programmeringsmodell och ett syntesverktyg för FPGA-kretsar. Minnesanvändning modelleras separat från beräkningar. Detta är en viktig egenskap, eftersom i huvudsak minnestransaktionerna kommer att begränsa systemets prestanda.

  • 280.
    Udo, Camilla
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för hälsovetenskap.
    Existential issues in surgical care: Nurses’ experiences and attitudes in caring for patients with cancer2012Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The overall aim of this thesis was to explore surgical nurses’ experiences of being confronted with patients’ existential issues when caring for patients with cancer, and to examine whether an educational intervention may support nurses in addressing existential needs when caring for patients with cancer. Previously recorded discussions from supervision sessions with eight healthcare professionals were analysed (I), written descriptions of critical incidents were collected from 10 nurses, and interviews with open questions were conducted (II). An educational intervention on existential issues was pilot tested and is presented in Studies III and IV. The intervention was the basis of a pilot study with the purpose of testing whether the whole design of the educational intervention, including measurements instruments, is appropriate. In Study III and IV interviews with 11 nurses were conducted and 42 nurses were included in the quantitative measurements of four questionnaires, which were distributed and collected. Data was analysed using qualitative secondary analysis (I), hermeneutical analysis (II), and mixed methods using qualitative content analysis and statistical analyses (III-IV). Results in all studies show that existential issues are part of caring at surgical wards. However, although the nurses were aware of them, they found it difficult to acknowledge these issues owing to for example insecurity (I-III), a strict medical focus (II) and/or lacking strategies (I-III) for communicating on these issues. Modest results from the pilot study are reported and suggest beneficial influences of a support in communication on existential issues (III). The results indicate that the educational intervention may enhance nurses’ understanding for the patient’s situation (IV), help them deal with own insecurity and powerlessness in communication (III), and increase the value of caring for severely ill and dying patients (III) in addition to reducing work-related stress (IV). An outcome of all the studies in this thesis was that surgical nurses consider it crucial to have time and opportunity to reflect on caring situations together with colleagues. In addition, descriptions in Studies III and IV show the value of relating reflection to a theory or philosophy in order for attitudes to be brought to awareness and for new strategies to be developed.

  • 281.
    Unander, Tomas
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    System integration of electronic functionality in packaging application2011Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    När efterfrågan på mer intelligenta och säkra produkter ökar så ökar även intresset för olika typer av sensorer. När kostnaden för dessa sensorer sjunker så kommer användandet av dessa att utökas till nya marknadssegment som tidigare inte använt denna typ av funktionalitet, som tillexempel pappersbaserade förpackningar, hygienartiklar och papper för grafiskttryck. Det är för närvarande ett stort intresse att utveckla tekniker som tillåter förpackningar att bli interaktiva och integrerade med olika digitala tjänster kopplade till Internet. I denna avhandling så presenteras systemintegrationen av en RFID baserad sensor plattform som tillhandahåller en avvägning mellan kommunikationsprestanda, kompabilitet med internationella standarder och kundanpassningsflexibilitet. Där man direkt på förpackningen kombinerar fördelarna med traditionell kiselbaserad elektronik med trycktelektronik för att kunna skapa intelligenta förpackningar. I avhandlingen presenteras och utvärderas även fem trycka fuktsensorer som är designade att kunna användas tillsammans med sensor plattformen. Den första sensorn mäter fukthalten i cellulosabaserade substrat. Den andra kan detektera höga fukthalter i luften. Den tredje, som aktiveras vid en händelse, producerar en elektrisk ström när den blir fuktig. Den fjärde sensorn använder sig av silverbaserade partiklar i nanostorlek för att mäta fukthalten i luften. Den femte sensorn är en beröringskänslig sensor som ger utslag av fukten i handen. Utöver dessa sensorer så utvärderas även ett koncept med en fuktsensor som kan läsas av på avstånd.

    Fokus är således att på system integrationsnivå, med hjälp av att kombinera kisel elektronik med tryckt elektronik, hitta den mest kostnadseffektiva lösningen med avseende på flexibilitet, sensor funktionalitet och att även kunna möta kommunikationsstandarderna.

  • 282.
    Vamstad, Johan
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för samhällsvetenskap.
    Governing Welfare: The third sector and the challenges to the Swedish Welfare State2007Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    The overall issue addressed in this thesis is the challanges to the Swedish welfare state. This topic has been the subject of several different interpretations in the academic as well as political debate in Sweden over the last decade. The first of two questions raised in this thesis is therefore what the main challenges to the Swedish welfare state are. It is concluded that the main challenges are the challanges to the representative democracy that originate in measures to meet the economic challenges to the Swedish welfare state by making it more efficient and rational. The main challenges to the Swedish welfare state are, therefore, a mix of interrelated economic and democratic challenges. A specific factor is tested for its possible impact on these challenges and that factor is third sector provision of welfare services. The second of the two research questions is therefore in what way and to what extent the third sector can influence how the identified challenges affect the welfare state. Childcare is selected as an example of a welfare service where there are a considerable proportion of third sector providers, primarily parent and worker cooperatives. The diversity, level of participation and service quality of different types of childcare is analysed with regard to how they affect the here presented challenges to the welfare state. It is concluded from this analysis that there are democratic benefits in the third sector provision of childcare that can act complementary to the challenged representative democracy. It is also concluded, however, that not all Swedish childcare can be provided by the third sector and that its democratic benefits therefore also should be produced by other types of childcare by imitating the third sectors active participation, small scale and independence. This study shows that Sweden is rapidly moving towards a greater diversity in its delivery of welfare service and that there are no policies or institutions for facilitating a more diverse service provision. An additional conclusion is for this reason that the outcome of the economic and democratic challenges varies with the direction of this diversification, which tells us that such policies and institutions are desirable. The Swedish welfare state will be getting a more diverse provision of welfare services regardless if there is any readiness for it or not and the results from this thesis show that the third sector is the non-public type of welfare provider that best facilitate the values and morals of the welfare state.

  • 283.
    van Vliet, Marja
    Mittuniversitetet, Fakulteten för humanvetenskap, Avdelningen för hälsovetenskap.
    Integrative Medicine in the Dutch healthcare system: prerequisites and tools for implementation2017Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    IM (Integrativ Vård mer adekvat term på svenska) är ett vårdkoncept/vårdansats som mer fokuserar på patienters välmående och läkeprocesser än enbart deras sjukdom. IM överlämnar makten och utbildar individen till att själv bli aktiva i sin vård, den framhäver vikten av en god vårdande relation och använder alla tillämpliga evidensbaserade metoder. Den hälsofrämjande grunden i IM är i linje med ett nyligen utvecklat hälsobegrepp, som beskriver hälsa som ”en persons förmåga till att anpassa sig och hantera utmaningar”. Utifrån den liknande grunden och förutsättningarna hos IM och det nya hälsobegreppet så kan en integration av dem vara en understödjande faktor för utveckling och implementering av IM. Utifrån en praktisk synvinkel så innebär en integrativ vårdansats att den som vårdar måste inneha specifika kompetenser och förmågor relaterade till bland annat socio-kommunikativ och självreflektiv förmåga, såväl som en reflektiv öppenhet till ett holistiskt perspektiv på hälsa. Tidigare forskning har visat att en Mind-Body Medicine (MBM) kurs potentiellt kan understödja utveckling av dessa kompetenser bland framtida vårdare. Denna avhandling avsåg i första hand att uppnå ökad insikt i förutsättningar och verktyg för implementering av Integrativ Vård. Mer specifikt syftade den till att beskriva attityder till, och utövande av IM bland Nederländska sjuksköterskor, samt undersöka stödet för det nya dynamiska hälsobegreppet (”en persons förmåga till att anpassa sig och hantera utmaningar”) bland intressenter inom Nederländsk Hälso- och Sjukvård. Vidare i andra hand, avsåg avhandlingen också att utvärdera förutsättningarna för att använda en MBM kurs som ett verktyg till att understödja och fostra ett mer integrativt förhållningssätt bland läkar- och sjuksköterskestudenter.

    Metod Både kvantitativ såväl som kvalitativ forskningsdesign tillämpades. Attityder till, och utövande av IM undersöktes i en semistrukturerad enkätstudie bland 355 Nederländska sjuksköterskor (studie I). Stödet för det nya hälsobegreppet undersöktes i en studie som genomfördes med mixad design, där i det första steget data från individuella- och fokusgruppintervjuer bland 140 intressenter genomgick en manifest innehållsanalys, och i det andra steget genomfördes en tvärsnittsstudie bland 1938 intressenter för att validera fynden från det första steget (Studie II). MBM kursen utvärderades i en kontrollerad, kvasi-experimentell interventionsstudie (71 deltagare/61 kontroller bland läkarstudenter, och 47 deltagare/64 kontroller bland sjuksköterskestudenter) med validerade frågeformulär (Studie III). Vidare även i en Fenomenologisk-Hermeneutisk ansats via individuella intervjuer med 11 läkar- och 15 sjuksköterskestudenter för att uppnå en djupare förståelse över MBM kursens betydelse för deltagarna (Studie IV).

    Fynd I studie I framkom att sjuksköterskorna övergripande hade en positiv attityd till IM. Patientcentrering och fokus på individens resurser, samt deras egna ansvar för att arbeta hälsofrämjande var områden som hade mest stöd bland både sjuksköterskor och andra intressenter. Dessa element ansågs också av intressenterna vara den mest positiva aspekten av det nya dynamiska hälsobegreppet (Studie II). Användandet av evidensbaserade komplementärmedicinska metoder och hälsofrämjande miljöer stöddes till viss del av sjuksköterskorna men brist på kunskap och brist på evidens förefaller vara hinder för integration i nuvarande vårdpraxis (Study I). I studie II framkom att begreppet hälsa uppfattades som att bestå i sex olika dimensioner; ”kroppslig funktion”, ”mental funktion och perception”, ”spirituell/existentiell dimension”, ”livskvalitet”, ”social-samhällelig inklusion” samt ”daglig funktion”. I samklang med patienter, så hade sjuksköterskor en bredare syn på hälsa än andra hälsoprofessioner. I studie III framkom långsiktiga positiva effekter av att delta i MBM kursen avseende i två dimensioner av empatisk förmåga (Personal distress och Empatic concern) bland läkarstudenterna, samt avseende upplevd stressnivå (perceived stress) och empati (personal distress) bland sjuksköterskestudenterna. I studie IV framkom att MBM kursen kan ses som ”en väg till inre medvetenhet och stöd till att knyta an till andra och den omgivande världen” vidare identifierades temana: ”en förmåga till en mer medveten närvaro”, ”en ökad uppfattningsförmåga och inre medvetenhet” samt ”att knyta an till andra människor på en djupare nivå”.

    Slutsats Utifrån resultaten i avhandlingens explorativa (I, II) del är slutsatsen att de observerade positiva attityderna, och uppfattningarna bland vårdgivare avseende IM och det nyutvecklade hälsobegreppet kan ses som viktiga facilitatorer för ytterligare implementering av IM i det Nederländska hälso- och sjukvårdssystemet. Vidare, den ökade förmågan att hantera stress, utveckla empatisk förmåga och mer öppenhet för nya perspektiv på hälsa och behandlingsalternativ hos läkar- och sjuksköterskestudenter efter deltagande i en MBM kurs (implementeringsdelen i denna avhandling, III, IV), stöttar antagandet att kursen kan ses som ett användbart verktyg för att understödja en mer integrativ vårdansats bland framtida vårdpersonal.

  • 284.
    Vestin, Jenny
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Biogeochemical Interactions between Soil, Soil Solution and Stream Water2007Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
  • 285.
    Vilches, Ana Paola
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Effects of Bio-Ash Amendments on the Metabolism of Ectomycorrhizal Fungi: A Method Development and Metabolomic Study2019Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Skogsekosystem har genom alla tider spelat en central roll i utvecklingen av vårt samhälle. Trä för konstruktioner, möbler och hushållsuppvärmning har varit tjänster från skogar sedan civilisationens början. Skogens välbefinnande kan därför anses grundläggande för vår existens. Idag har vårt samhälle utvecklats och behovet av skogsråvara ökar kontinuerligt. Detta i kombination  med minskande fossila reserver och den inverkan som användningen av dessa reserver har haft på vår miljö har återigen gjort skogen till ett av de viktigaste alternativen för att åstadkomma en hållbar utveckling. Detta innebär att vi måste öka vår kunskap om hur olika former av skogsbruk påverkar miljön i skogsekosystemen.

     Användningen av skogsråvara som energikälla ger upphov till stora mängder aska. Askan innehåller höga halter av de baskatjoner som en gång har transporteras från jorden till de övre delarna av träden. Återföring av aska har därför föreslagits som en skogsbrukspraxis för att motverka den försurning som en omfattande avverkning kan ge upphov till. Eftersom återföring av aska kan ha stora effekter på skogen är det viktigt att förstå vilka dessa effekter är och hur omfattande de kan vara.

    Denna avhandling fokuserar på de effekter som askåterföring till skogsmark kan ha på metabolismen hos ektomykorrhizasvampar, det vill säga svampar som kan kolonisera rötter och bidra till trädens upptag av näringsämnen och vatten från jorden. Arbetet uppnåddes med ett in vitro metabolomiskt tillvägagångsätt på åtta arter av ektomykorrhizasvampar som förekommer normalt i boreala skogar. En riktad metabolomisk studie genomfördes för att studera effekterna av olika doser av aska på tillväxt, yttre pH och utsöndring av lågmolekylära organiska syror samt aminosyror och hydroxamatsideroforer. Denna studie kompletterades med en mer generell metabolomikstudie där effekterna av aska på svamparnas totala metabolism studerades.

    I ett arbete som detta är det viktigt med tillförlitliga metoder. En stor del av detta arbete har varit att utveckla nya kemiska analysmetoder. En metod för analys av aminosyror utan derivatisering och samtidigt kompatibel med masspektrometrisk detektion behövde utvecklas och valideras. Detta resulterade i en robust metod som fungerade väl med extern kalibrering och uppvisade bra detektionsnivåer samt förhållandevis hög genomströmning. Vidare så utvecklades även en metod för att kunna upptäcka förekomst av låga halter av sideroforer i komplexa prover med stöd av masspektrometri.

    De metabolomiska studierna visade att exponering for bioaska ledde till ökad utsöndring av lågmolekylära organiska föreningar hos alla studerade arter. Huvudsakligen tenderade svamparna till att utsöndra mer av samma föreningar som registrerades för kontrollerna utan tillförsel av aska. I vissa fall ledde exponeringen även till utsöndring av nya föreningar. Det fanns också undantag där askan snarare hade negativ inverkan på utsöndringen av vissa metaboliter. Generellt var dessa negativa effekter av lägre magnitud än de positiva effekterna. Båda metabolomikstudierna visade en differentiering mellan basidiomyceter och ascomyceter. Den riktade metabolomiska studien antydde en kompromiss mellan användningen av kol för ackumulering av biomassa respektive utsöndring av organiska föreningar med låg molekylvikt, där ascomyceterna tycktes ackumulera mer kol som biomassa jämfört med de basidiomyceter som ingick i studien. Den mer generella metabolomikstudien, visade också att ascomyceterna var de arter som utsöndrade flest antal metaboliter som påverkades av bioaska, antingen i positiv eller i negativ riktning.

    Tillsats av extraherad bioaska till odlingsmediet vid experimentets början ledde till ökat pH, men detta motverkades med tiden av metabolismen genom utsöndringen av organiska syror. Askbehandlingen resulterade i ökad utsöndring av organiska syror med låg molekylvikt för fem av de åtta studerade arterna och speciellt för Cortinarius glaucopus. Behandlingen resulterade också i ökad utsöndring av aminosyror från Tomentellopsis submollis och av ferricrocin från Hymenoscyphus ericae.

    Ingen av de metaboliter som påverkades signifikant av bioaska visade sig vara gemensam för alla studerade arter. Detta indikerar att under de odlingsbetingelser som användes så var det huvudsakligen den sekundära metabolismen som påverkades.

     

  • 286.
    Voie, Christian Hummelsund
    Mittuniversitetet, Fakulteten för humanvetenskap, Avdelningen för humaniora.
    Nature Writing of the Anthropocene2017Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    The point of departure for this study is the hypothesis that the American genre of nature writing has reached an important crossroads in the way it describes the human-nature relationship. My study argues that the awareness of the large-scale environmental changes that are signaled in terms such as the Anthropocene has changed the way nature writers approach their genre. Where traditional nature writing would tend to posit a separation between pristine and humanized environments, the nature writing of the Anthropocene emerges from the awareness that environmental impacts have reached a scope where no such distinction can be made. The traditional narrative of retreat to pristine nature or the wilderness from civilization has thus been replaced in Anthropocenic nature writing with the narrative of confrontation with a natural environment impacted by humans. This is a dystopian tendency in the genre, in which descriptions of nature are increasingly characterized by the writer’s concerns over what is happening to the landscape in question, and what the future might hold in a world where industrial humanity is affecting all ecological processes. Such literature increasingly foregrounds the best available environmental science, and the texts mark a shift from the traditional focus on spiritual connections with the environment, towards more material and functional understandings of the role of humanity in the complex organic and inorganic dynamics that maintain the world’s ecosystems. This dissertation analyzes the emergence of Anthropocenic awareness in selected texts of contemporary American nature writing with reference to its five main features: scientific interest in the function of ecosystems, interest in the agency of matter rendered through what is referred to as material nature writing, the dignification of the overlooked, the environmental landscape of fear, and a turn in the genre towards matters of environmental justice. Even though what I refer to as Anthropocenic nature writing may seem dystopian, this dissertation foregrounds the various ways in which the narrative of confrontation with the human also invites activism and engagement in the hope of stimulating change and environmental justice.

  • 287.
    von Krogh, Torbjörn
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Understanding Media Accountability: Media Accountability in Relation to Media Criticism and Media Governance in Sweden 1940-20102012Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The concepts of media accountability, media criticism and media governance are analysed and discussed in a Swedish setting; how they relate to each other and interact. This is achieved by using various methods – a survey to editors, analy- ses of parliamentary debates, interviews, direct observation and document stu- dies – in studying different stakeholders, media representatives and governance conditions in Sweden during the last 70 years.

    The findings point in a direction of dynamic complexities with a central role for media criticism. The type, level and intensity of media criticism may affect the functioning of the media governance structure and is a vital part of the media accountability process. The media governance structure – which in addi- tion to media criticism is influenced by international conditions, technological developments and political factors – may in turn affect the media accountability process. In this process, media representatives aim to defend obtained positions of societal influence, achieve and maintain positive PR and enhance editorial quality at the same time.

    Media criticism may start a substantial media accountability process if the discontent is widespread and not countered by market approval or political iner- tia. The process is facilitated if the critique is connected to more than one frame of accountability and if stakeholders see opportunities for dual objectives. Very strong and widespread media criticism may be difficult for media organizations to neglect.

    The accountability process in Sweden has become less dependent on corpora- tive negotiations between organized interests and political assemblies. Instead, two other tendencies seem to have emerged: on the one hand a possibility for media organizations to favour such accountability processes that they are able to control, and on the other hand the rise of a rich variety of sometimes short-lived accountability instruments that may develop for specific occasions and are difficult to control.

  • 288.
    Wall, Erika
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för samhällsvetenskap.
    Riskförståelse: Teoretiska och empiriska perspektiv2010Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Föreliggande avhandling introducerar begreppet riskförståelse (sense-making of risk) och dess syfte är att teoretiskt och empiriskt studera detta begrepp. Särskild vikt har lagts vid att undersöka riskförståelsens olika beståndsdelar, dess rumsliga dimensioner samt relationen mellan riskförståelse och beteenden. Med utgångspunkt i att risker definieras och skapas med utgångspunkt i gemensamma föreställningar inom ramen för ett specifikt socialt sammanhang fokuseras betydelsen av sociala och kulturella kontexter. Med detta som grund har begreppsutvecklingen i avhandlingen bland annat inspirerats av Karl Weicks och Alfred Schütz teorier om individens meningsskapande.

    I de olika delstudier som ingår i avhandlingen studeras olika aspekter av individens riskförståelse och risk-/riskreducerande beteenden. Genom att utgå ifrån Weicks teorier om meningsskapande illustrerar riskförståelsebegreppet individens personliga förståelse för olika risker. De normer och värderingar som omger individen i det sociala och rumsligt definierade sammanhang som hon befinner sig i är avgörande för vilken förståelse hon kan skapa för en risk. Genom att använda bland annat Schütz teorier om sociala relationer betydelsen och funktionen av individens meningsstruktur synliggjorts som bas för individens riskförståelse. Meningsstrukturen består av flera olika beståndsdelar och i avhandlingen lyfts fyra av dessa fram: egna erfarenheter, värderingar, platsanknytning och social skiktning. Genom att individen relaterar den risk hon möter till den egna meningsstrukturen skapas förståelse för den specifika risken. Meningsstrukturens funktion är att bistå individen med förenklingar av verkligheten för att göra det möjligt att skapa mening kring olika risker. En viktig aspekt vad gäller meningsstrukturen är att den i hög grad är socialt konstruerad genom socialiseringsprocesser i det specifika rumsliga sammanhang som individen befinner sig i. Detta innebär att individens förståelse av risk relateras till olika sociala och rumsliga sammanhang; individens riskförståelse är således platsbunden.

    Avhandlingen bygger på fyra delstudier vilka presenteras i artikelform. Datamaterial samlats in genom både enkätundersökningar och fokusgruppsintervjustudier för att undersöka detta fenomen utifrån olika metodologiska perspektiv.

    I den första artikeln, baserad på en fokusgruppsintervjustudie, introducerades begreppet riskförståelse. De empiriska resultaten visade att begreppet kan användas för att synliggöra hur ungdomar med liknande riskperceptioner skiljer sig åt i sin förståelse av olika risker. En teoretisk modell utformades som beskriver individens riskförståelse med utgångspunkt i två dimensioner. Den första dimensionen relaterade till i vilken grad individens riskförståelse är platsbunden och den andra till om individens riskförståelse främst kan beskrivas som kollektivt eller individuellt orienterad. Empiriskt åskådliggjorde resultaten att ungdomarna i studien uppfattade samma risker som allvarliga men att deras riskförståelse skilde sig åt och att dessa skillnader kunde härledas till boendemiljö.

    I den andra artikeln studerades ungdomars riskbeteenden i trafiken. I studien gjordes logistiska regressionsanalyser på ett datamaterial hämtat från Trafiksäkerhetsundersökningen 2001. En viktig slutsats från denna studie var att det är viktigt att inte bara ta hänsyn till individens riskförståelse, utan också till rumsliga sammanhang vad gäller att förklara individens beteenden i relation till risk.

    Den tredje artikeln, som baserades på en fokusgruppsintervjustudie, var en tillämpning av begreppet riskförståelse med avseende på risker i trafiken. Undersökningen fokuserade på relationen mellan platsanknytning och riskförståelse. Studien visade att olika aspekter av platsanknytning har betydelse för individens riskförståelse. Social tillhörighet hade särskilt stor betydelse vad gäller riskförståelse hos de ungdomar som deltog i studien men också de andra dimensioner av platsanknytning som studerades (yttre förhållanden, ömsesidigt beroende och värdegemenskap) hade betydelse för riskförståelse hos respondenterna i studien.

    I den fjärde delstudien genomfördes klusteranalys på ett datamaterial från undersökningen Samhälle och värderingar 2008. Det viktigaste resultatet från denna studie var den teoretiska begreppsutveckling som presenterades. Denna innebar att meningsstrukturen lyftes fram som bas för individens riskförståelse. Vidare gjordes en operationalisering av individens meningsstruktur, vilken användes för att gruppera individer. Den empiriska tillämpningen visade sig vara användbar vad gäller att studera skillnader i beteenden mellan olika grupper i samhället då gruppering utifrån meningsstruktur bidrog till att förklara skillnader i risk-/riskreducerande beteenden.

    I kappan förs de olika delstudierna samman och begreppsutvecklingen i fråga om riskförståelse beskrivs. Begreppet är av särskild vikt vad gäller att beskriva hur sociala och rumsliga sammanhang ingår i individens riskförståelse. Den begreppsutveckling som gjorts har också visat att individen baserar sin riskförståelse på en meningsstruktur vilken också kan användas för att undersöka risk- och riskreducerande beteenden. Avhandlingens viktigaste bidrag är den teoretiska begreppsutvecklingen ifråga om hur individen skapar sin personliga riskförståelse. Ytterligare teoretisk begreppsutveckling och empiriska tillämpningar bör dock göras i kommande studier för att säkerställa begreppets generella användbarhet. Genom detta kan riskförståelse bli en viktig del i en specifikt sociologisk begreppsapparat med fokus på hur individen förhåller sig till risk.

  • 289.
    Wallin, Erika
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    The Scents of Nature: Identification and Synthesis of Bioactive Compounds Used in Insect Communication2014Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Pest insects cause great financial losses in the forest and food industry every year. To fight these pests industries have used insecticides, which are sometimes harmful to nature and humans. One potential way of avoiding insecticides is the use of integrated pest management based on insect communication, which would offer species-specific methods for protecting forest and food resources. Insects use chemicals known as semiochemicals for both intra- and interspecies communication. By learning how insects use these semio-chemicals to talk to each other we can eavesdrop and mimic their communication for our benefit. One research area dealing with these questions is chemical ecology, which is an interdisciplinary area as knowledge in chemistry and biology is required. Collaborations between groups within and outside of Sweden are essential in order to make progress in this field of research.

    This thesis presents the identification and synthesis of semiochemicals from several insect species, most of which are considered to be pests. Synthesised compounds have been sent to collaboration partners around Sweden and Europe for biological evaluations.

    Studies of the African butterfly, Bicyclus anynana, have unravelled particular biological phenomena that may aid in the understanding of the Bicyclus genus, though recognizing individual species variation is crucial. In 2008 the putative male sex pheromone of B. anynana was determined to consist of three compounds: hexadecanal, (Z)-9-tetradecenol and 6,10,14-trimethylpentadecan-2-ol, and the specific stereoisomer for 6,10,14-trimethylpentadecan-2-ol has been determined in this thesis. The ratio of 6,10,14-trimethylpentadecan-2-ol and the corresponding ketone were investigated for seventeen Bicyclus species (including B. anynana) that live in overlapping regions in Africa. The stereochemistry was determined for most of the species and may provide a way to chemically distinguish them.

    The orchid bees, Euglossa spp, are important pollinators of many orchids in Central America. Insight about pollination and conservation of endangered orchid species may be possible by gathering more information about the Euglossa genus. Males of the Euglossa genus have pouch-like structures on their hind legs where they store compounds collected from their surroundings. 6,10,14-Trimethyl-pentadecan-2-one is a common component of leg extracts from Euglossa imperialis, E. crassipunctata and E. allosticta, the specific stereochemistry of which has been determined in this thesis. Another, different compound was found in high amounts in E. viridissima and its structure has been elucidated; several synthetic pathways are under investigation to obtain the target compound.

    Bed bugs (Cimex lectularius and C. hemipterus) are an ectoparasite that feed on human blood, and the number of reported infestations of these parasites has increased considerably during the last decade. Two 5th instar nymph-specific compounds, 4-oxo-hexenal and 4-oxo-octenal, were identified and synthesised.

    Utilizing domestic dogs (Canis lupus familiaris) in the identification of bed bug infestations has become popular during recent years. Their training is usually conducted using live bed bugs, however this thesis describes an alternative method of teaching dogs to find infestations. This alternative method is based on synthetic compounds and dogs trained in this manner have achieved a high positive indication rate.

    Two species of the tiny, Acacia leaf-eating insect pests in Australia known as thrips, Kladothrips nicolsoni and K. rugosus, have been investigated by means of larval extracts and have been shown to contain large amount of (Z)-3-dodecenoic acid which was synthesised and tested in bioassays.

    Fruit flies are common pests on fruit in almost every private household. Even though fruit flies has been investigated extensively, their chemical communication has not been completely elucidated. (Z)-4-undecenal was identified as a compound emitted by females, it was synthesised in high stereoisomeric purity and evaluated in biological assays.

  • 290.
    Walter, Karin
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    The use of Fenton chemistry for reducing the refining energy during TMP production: the effect of free ferrous and free or chelated ferric ions2013Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The potential of using acid hydrogen peroxide under Fenton conditions to lowerthe electrical energy consumed during the production of Black spruce (Piceamariana) thermomechanical pulp (TMP) was investigated in pilot scale. Thechemical system, which consisted of ferrous sulphate, hydrogen peroxide andoptionally an enhancer (such as a chelating agent), was evaluated as an inter-stagetreatment. The produced TMPs were thoroughly characterised in order to explainthe effect of the chemical system on fibre development and to be able to propose amechanism for the impact on refining energy reduction. The possibility to improvethe optical properties by washing, chelating and sodium dithionite or hydrogenperoxide bleaching the treated pulps was evaluated. The system of lignocellulosicmaterial, a Norway spruce (Picea abies) TMP, and Fenton chemistry was alsoevaluated in a model study to understand more about how conditions such as e.g.initial pH, dissolved organic material and reaction time affect the reactions.Ferrous and ferric ions (free and chelated) and different anions were evaluated.Moreover, it was examined whether hydroxyl radicals could be detected andmonitored.The results obtained in pilot scale showed that it is possible to significantly reducethe specific energy consumption by approximately 20% and 35% at a freenessvalue of 100 ml CSF or a tensile index of 45 Nm/g by using 1% and 2% hydrogenperoxide respectively. The energy reduction was obtained without any substantialchange to the fractional composition of the pulp, although tear strength wasslightly reduced, as were brightness and pulp yield. No major differences betweenthe reference pulp and the chemically treated pulps were found with respect tofibre length, width or cross-sectional dimensions. However, the acid hydrogenperoxide-treated pulps tended to have more collapsed fibres, higher flexibility, alarger specific surface area and a lower coarseness value. The yield lossiiiaccompanying the treatment was mainly a consequence of degradedhemicelluloses. It was also found that the total charge of the chemically treatedpulps was higher compared to the reference pulps; something that may haveinfluenced the softening behaviour of the fibre wall.A washing or chelating procedure could significantly reduce the metal ion contentof the chemically treated TMPs. The amount of iron could be further reduced to alevel similar to that of untreated pulps by performing a reducing agent-assistedchelating stage with dithionite. The discoloration could not, however, becompletely eliminated. The brightness decrease of the treated pulps was thereforenot only caused by the greater iron content in the pulp, but was also dependent onthe type of iron compound and/or other coloured compounds connected with theacid hydrogen peroxide treatment. Oxidative bleaching using hydrogen peroxidewas more effective than reductive bleaching using sodium dithionite in regainingthe brightness that was lost during the energy reductive treatment.From the model study and by using a chemiluminescence method, it could beconcluded that hydroxyl radicals were present in the system of Fenton chemicalsand lignocellulosic material (TMP). Initial pH, retention time, pulp consistency,type of catalyst (free or chelated) and dissolved organic material had an impact onthe reactions between TMP and acid hydrogen peroxide. Different anions(sulphate, nitrate and chloride) of ferric ion salt gave a similar catalytic effect.There appeared to be more reactions with the TMP when there was less dissolvedorganic material in the liquid phase from the start. A catalyst of ferrous sulphatehad a greater impact on the pulp (increased total fibre charge and carbonyl groups,more dissolved organic material in filtrate) than ferric ions chelated withethylenediaminetetraacetic acid at an initial pH of about 3-7. If using ferric-EDG(ethanol diglycinic acid) as catalyst, the measured effect on the pulp was similar orless compared to using ferrous sulphate. Ferric-EDG, however, gave higherhydrogen peroxide consumption and more detectable hydroxyl radicals than usingferrous sulphate (initial pH 5-8). It is likely that the iron catalyst must bind to theTMP, or be in close proximity to it, for the hydroxyl radicals to be able to react withthe material.A mechanism was proposed: the hydroxyl radicals generated in the Fentonreaction will probably attack and oxidise the available outer fibre surfaces,weakening these layers, and simultaneously dissolve some of the organic material.This can facilitate fibre development, give a better bonding pulp and reduce theelectrical energy required during refining.

  • 291.
    Wang, Airong
    Mittuniversitetet, Fakulteten för humanvetenskap, Avdelningen för humaniora.
    Learning English in a Multi-User Virtual Environment: Exploring Factors Affecting Participation2017Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Online language learning and teaching is a field that has received a significant amount of research attention. What factors could affect student participation in simpler online learning environments has been investigated by researchers, but there has been limited study of factors affecting participation in complex Multi-User Virtual Environments.

    By using the typical Multi-User Virtual Environment Second Life, three English courses offered by Swedish universities were examined in this thesis. The courses were video-recorded, and selected parts of the recordings were transcribed. The transcribed recordings were complemented by author(s)’ observation, participants’ reflection, an online questionnaire and an online interview. Participation from the courses was measured both quantitatively and qualitatively. Quantitative methods were used to measure, for example, floor space, number of utterances, turn length, number of turns; the qualitative analysis centered on, for instance, utterance functions, discourse analysis, and Conversational Analysis.

    The results were published in five papers that focused on different central factors affecting participation in Second Life. In this thesis, the findings from those articles are synthesized. Furthermore, on the basis of the findings, a general model of factors affecting participation is presented and discussed to highlight that different factors interrelate and that some factors are particularly important in terms of affecting participation in Multi-User Virtual Environments. These are students’ technical skills, task design, course design, technical support, and Second Life technology. The complex technology also places critical demands on teachers’ technical skills, teaching strategies, and roles that teachers should play. Finally, this thesis argues that it is important to choose a suitable technology for an English course.

  • 292.
    Wang, Qinghua
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Traffic Analysis, Modeling and Their Applications in Energy-Constrained Wireless Sensor Networks: On Network Optimization and Anomaly Detection2010Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Wireless sensor network (WSN) has emerged as a promising technology thanks to the recent advances in electronics, networking, and information processing. A wide range of WSN applications have been proposed such as habitat monitoring, environmental observations and forecasting systems, health monitoring, etc. In these applications, many low power and inexpensive sensor nodes are deployed in a vast space to cooperate as a network.

    Although WSN is a promising technology, there is still a great deal of additional research required before it finally becomes a mature technology. This dissertation concentrates on three factors which are holding back the development of WSNs. Firstly, there is a lack of traffic analysis & modeling for WSNs. Secondly, network optimization for WSNs needs more investigation. Thirdly, the development of anomaly detection techniques for WSNs remains a seldomly touched area.

    In the field of traffic analysis & modeling for WSNs, this dissertation presents several ways of modeling different aspects relating to WSN traffic, including the modeling of sequence relations among arriving packets, the modeling of a data traffic arrival process for an event-driven WSN, and the modeling of a traffic load distribution for a symmetric dense WSN. These research results enrich the current understanding regarding the traffic dynamics within WSNs, and provide a basis for further work on network optimization and anomaly detection for WSNs.

    In the field of network optimization for WSNs, this dissertation presents network optimization models from which network performance bounds can be derived. This dissertation also investigates network performances constrained by the energy resources available in an indentified bottleneck zone. For a symmetric dense WSN, an optimal energy allocation scheme is proposed to minimize the energy waste due to the uneven energy drain among sensor nodes. By modeling the interrelationships among communication traffic, energy consumption and WSN performances, these presented results have efficiently integrated the knowledge on WSN traffic dynamics into the field of network optimization for WSNs.

    Finally, in the field of anomaly detection for WSNs, this dissertation uses two examples to demonstrate the feasibility and the ease of detecting sensor network anomalies through the analysis of network traffic. The presented results will serve as an inspiration for the research community to develop more secure and more fault-tolerant WSNs.

  • 293.
    Warne, Maria
    Mittuniversitetet, Fakulteten för humanvetenskap, Avdelningen för hälsovetenskap.
    Där eleverna är: Ett arenaperspektiv på skolan som en stödjande miljö för hälsa2013Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Hälsa skapas inte i ett vakuum utan i relation mellan individer och omgivning. Skolan är därför en viktig arena för barn och ungdomar eftersom de tillbringar större delen av sin vakna tid där. Tidigare forskning har framförallt riktats mot riskfaktorer relaterade till barn och ungas psykiska ohälsa, mindre mot vad som främjar och stärker möjligheterna till deras positiva hälsa. Genom ett salutogent perspektiv kan kunskap erhållas om faktorer som bidrar till en stödjande miljö för hälsa. För att få förståelse för nya generationers behov och värderingar behöver elever göras delaktiga i studier och utveckling av sin egen vardagsmiljö.

    Avhandlingens syfte var att studera skolan som en stödjande miljö för hälsa genom att involvera elever och att finna metoder för att studera de positiva aspekterna av hälsa. Artiklarnas syften inkluderade utmaningar och möjligheter att använda en metod för ökad delaktighet, fördjupa förståelsen om aspekter som främjar hälsa och lärande, med särskilt fokus på delaktighet och stöd samt hur positiv hälsa kan mätas.

    Elever på en gymnasieskola valdes som deltagare i två kvalitativa studier. Metoden photovoice studerades genom ljudinspelning av elevernas dialog under arbetet med photovoice och deras och lärarnas synpunkter under fokusgruppsintervjuerna. Data analyserades med innehållsanalys (I). Grundad teori användes för att studera elevernas syn på vad som var viktigt för hälsa och lärande (II). En enkät användes för att ta fram en positiv hälsoskala och för att studera faktorer associerade till hälsa bland elever årskurs 6-9. Enkäten besvarades av 1527 elever (52,3% flickor, 47,7% pojkar) i årskurs 6-9 i skolorna i Östersunds kommun. Svarsfrekvensen var 80%. En principalkomponentanalys användes anpassa och validera en positiv hälsoskala till åldersgruppen 12-16 år (III). För att studera associationen mellan faktorer som kunde vara associerade till positiv hälsa valdes multipel logistisk regressionsanalys (IV).

    Resultatet visade att photovoice fungerade som en metod i gymnasieskolan för ökad delaktighet i frågor relaterade till hälsa och lärande. Metoden behövde dock anpassas till elevgruppen. Photovoice upplevdes som stimulerande men också utmanade av både lärare och elever. Kritiska aspekter för metodens användbarhet var knutna till lärarrollen och den demokratiska organisationen (I). Elevernas syn på vad som främjade hälsa och lärande var relaterat till bemötande, personligt och pedagogiskt stöd samt möjligheter till återhämtning. Resultatet visade också att eleverna upplevde att skolan bidrog till att skapa skillnad mellan dem som upplevde sig vara låg- respektive högpresterande (II). Den positiva hälsoskalan (PHS) visade sig vara valid för elever 12-16 år och skalan bör kunna användas i ett sytematiskt hälsofrämjande arbetet där utgångspunkten är ett salutogent perspektiv (III). Faktorer associerade till positiv hälsa bland flickor och pojkar, 12-16 år, var: upplevd delaktighet i klassrummet, stöd från lärare och kamrater samt stöd från båda föräldrarna. Socioekonomisk status, mätt som att ha pengar som kompisar, visade sig vara oberoende associerat till positiv hälsa (IV).

    Slutsatsen var att betydelsefulla faktorer för en stödjande miljö för hälsa i skolan är; elevers upplevelse av och möjlighet till delaktighet i klassrummet och i skolans arbetsmiljö, personligt stöd från lärare såväl som stöd i undervisningen, stöd från kamrater och förutsättningar för återhämtning under och efter skoldagen. Samtidigt visade resultatet att det finns skillnader mellan olika grupper av elever relaterat till hälsa och stöd.

    För att utveckla en stödjande miljö för hälsa i skolan kan photovoice användas för att involvera eleverna och upptäcka unika aspekter på den enskilda skolan. Med hjälp av den positiva hälsoskalan (PHS) kan främjande faktorer kartläggas, vilket ökar möjligheterna till ett systematiskt hälsofrämjande arbete med ett salutogent perspektiv.

  • 294.
    Weimer, Kerstin
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för psykologi och socialt arbete.
    Behavior Change Towards a Sustainable Lifestyle – Effects of Interventions and Psychological Factors on Pro-Environmental Behaviors2019Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Klimatförändringar på grund av global uppvärmning som är förorsakad av människan är allvarliga utmaningar för planeten. Det är därför nödvändigt att människans individuella beteende förändras mot att bli mer miljövänligt. Människans beteende är emellertid komplicerat, och främjande av beteendeförändringar kräver en gedigen förståelse för hur människor beter sig i olika situationer och sammanhang.

    Tidigare forskning har visat på flera skäl till varför vi människor inte beter oss i överensstämmelse med vår kunskap om hotet från klimatförändringarna.Förutom strukturella hinder, kan det finnas andra skäl relaterade till psykologiska hinder såsom övertygelser, värderingar och sociala normer, vilka begränsar oss när det gäller att anpassa oss till mer miljövänliga val och beteenden. Övergripande syften med denna avhandling har varit att undersöka hur olika interventioner påverkar energibesparing i bostäder och konsumtion av ekologisk mat i syfte att främja miljövänligt beteende, att utforska upplevelserna av en intervention för energibesparing utifrån deltagarnas perspektiv, samt att undersöka hur värderingar, attityder och andra psykologiska faktorer kan förutsäga miljövänligt beteende och intentioner till miljövänligt beteende.

    Avhandlingen innehåller fyra studier. Den första är en enkätundersökning, i vilken den predicerande styrkan av värderingsorientering, medvetenhet om konsekvenser, miljöhänsyn, moralisk bedömningskompetens, kontroll-lokus och känsla av sammanhang undersöktes med avseende på åtta miljövänliga beteenden och beteendeintentioner. Endast värderingstypen universalism predicerade avsedda beteenden, med attityderna medvetenhet om konsekvenser för biosfären och miljöhänsyn för biosfären som medierande variabler. Detta skulle kunna indikera att påvisade bestämningsfaktorer för ett enda beteende förmodligen inte kan tillämpas för andra beteenden som beroende variabler. Således skulle separata analyser för varje typ av beteende kunna ha varit mer framgångsrika i att bekräfta de undersökta variablerna som bestämningsfaktorer för miljövänligt beteende och beteendeintentioner.

    Den andra studien är en randomiserad kvasi-experimentell studie. Denna fältstudie undersökte effekten av feedback på energiförbrukningen i bostäder. Under en period av åtta veckor registrerades differentierad förbrukning av hushållsel, avseende vardagliga beteenden i hemmet, för 15 hushåll via ett internetbaserat system. Feedback baserad på Relational Frame Theory användes för att öka motivationen till att spara energi och uppföljningar analyserade vidmakthållandet av eventuella förändringar under ytterligare tre månader. Psykologiska faktorer, såsom värderingar, attityder, moralisk bedömningskompetens, kontroll-lokus och känsla av sammanhang mättes med hjälp av web-enkäter. Inga signifikanta effekter av feedback på energiförbrukningen kunde fastställas. Den begränsade storleken på urvalet samt faktum att förbrukningen av varmvatten inte kunde registreras diskuterades som förklarande faktorer.

    I avhandlingens tredje studie genomfördes semi-strukturerade intervjuer bland de åtta hushåll som deltagit fullt ut i den andra studiens intervention. De transkriberade intervjuerna blev föremål för kvalitativ innehållsanalys i syfte att utforska deltagarnas upplevelser. Å ena sidan beskrevs dessa upplevelser som en kamp för att övervinna inre och yttre hinder samt känslor av motsägelse och ambivalens, vilket kan ses som uttryck för de krav som en intervention ställer på deltagarna. Å andra sidan beskrevs även känslor av förmåga och motivation, ett samspel mellan tillfredsställelse och framsteg som representerar de möjligheter som erbjuds deltagare i denna typ av intervention. Resultatet understryker vikten av att ta hänsyn till specifika strategier när nya interventioner för energibesparing i bostäder ska utformas.

    Slutligen, i den fjärde studien, genomfördes en experimentell fältstudie där beteende-interventioner med hjälp av nudges användes i syfte att främja konsumtionen av ekologisk frukt och grönsaker. Under fyra dagar (en dag varannan vecka) mättes konsumtionen av såväl ekologiskt som konventionellt producerad frukt och grönsaker i en livsmedelsaffär där konsumenterna exponerades för information i kombination med emotionella bilder eller budskap som stimulerade sociala normer. Den dagliga konsumtionen utan exponering av nudges registrerades under fyra andra dagar (en dag varannan vecka, växelvis med nudging-dagarna). Proportionen av sålda ekologiska produkter, i jämförelse med den totala försäljningen av de utvalda frukterna och grönsakerna, var något högre under dagar med nudging om skillnader i pris mellan konventionella och ekologiska produkter var små. Denna begränsade effekt av nudging försvann när priset för ekologiska produkter var betydligt högre än priset för konventionellt producerade produkter. Resultaten av den här studien antyder att det finns ett behov att vidta åtgärder för att kompensera för de rådande skillnaderna i pris mellan ekologiska och konventionella produkter. Detta kan göras, till exempel, genom att applicera en kombination av alla tillgängliga verktyg för nudging för att förstärka effekten av nudging, liksom att samla personliga data från konsumenterna för att få kunskap om deras attityder gentemot val av ekologiska produkter.

    Sammantaget bekräftar de övergripande resultaten i studierna i denna avhandling komplexiteten i det mänskliga beteendet och i förändring av beteende. Många frågor kvarstår obesvarade och förslag på hur man kan utveckla forskningen inom avhandlingens område diskuteras.

  • 295.
    Widenstjerna, Thomas
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för humaniora och samhällsvetenskap.
    Vem väljer vem och varför?: Om betydelsen av homosocialitet och personliga kontakter i partiers nomineringsprocesser2020Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    The aim of this thesis was to study Swedish intra-party nomination processes for political appointments at the municipal, regional and national levels. This was accomplished by studying whether, and if so how, nomination processes are affected by identification and the existence of personal contacts and networks, based in part on homosociality and network capital. Homosociality proceeds from the assumption that people who are perceived as being similar are preferred at the expense of those perceived as different. Network capital is based on the premise that personal contacts and networks are a form of capital that can be accumulated and spent to achieve set goals, such as being nominated for a political appointment. The empirical material comprises 32 semi-structured in-depth interviews with members of nomination committees (selectors) in the Västernorrland region of Sweden that participated in nomination processes in connection with local, regional and national elections in 2010 and 2014. The respondents were selected through snowball sampling and were asked during the interviews how they believe their personal views on candidates and personal networks affect the selection processes of nomination committees. The analysis shows that nomination committees preferred candidates whom they perceived to be similar to them, in ways including socioeconomic factors, age, gender, or geographical origins. The analysis also shows that access to personal contacts often determined whether or not a candidate was nominated. This was partly because personal contacts worked as references for new politicians that were used to ameliorate the risk of nominating individuals who might be perceived as unsuitable and partly because people in the networks of selectors or those of their friends and family were often regarded as more credible. Another observation was the central role of the local level in the parties’ recruitment and nomination activities. The analysis also showed that long-term political experience at the local level was usually required of the people who stood as candidates for regional or national political appointments. Lacking local experience, the opportunity to be nominated for these appointments was virtually nil. As well, the analysis showed that homosociality can promote the formation of network capital, as people who perceive that they are similar each other are attracted to each other and form networks that become part of overall network capital.

  • 296.
    Wiklund, Hanna
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Lattice Boltzmann simulations of two-phased flow in fibre network systems2012Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Two-phase flow in microfluidic systems is of great interest for many scientificand engineering problems. Especially in the pulp and paper area, the problems spanfrom fibre-fibre interactions in the consolidation process of papermaking to edgewickingin paper board during the aseptic treatment of liquid packaging.The objective of this thesis is to gain a fundamental understanding of the microfluidicmechanisms that play a significant role in various problems of two-phaseflow in fibre networks. To achieve this objective a new method for the treatment ofwetting boundary conditions in the lattice Boltzmann model has been developed.The model was validated and compared with the previous treatments of wettingboundary conditions, by using two test cases: droplet spreading and capillary intrusion.The new wetting boundary condition was shown to give more accurate resultsfor a wider range of contact angles than previous methods, and capillary intrusioncould be simulated with higher accuracy even at a relatively low resolution.As an application of the developed method, two examples of two-phase flowproblems in fibre networks are taken: the shear resistance of liquid bridges, as relatedto the wet web strength, and liquid penetration into porous structures, as related toedge-wicking in paper board. The shear resistance force was shown to depend verylittle on surface tension and contact angle. Instead, the shear resistance is a dynamicforce and a major contributing factor is the distortion of the flow field caused bythe presence of interfaces. This distortion of the flow field is size-dependent: thesmaller the bridge, the larger the proportion of the distorted flow field and thus alarger shear resistance force per unit width. In other words, multiple small bridgeshave an enhancement effect on shear resistance. The results from the simulations ofliquid penetration into porous structures showed that the discontinuities in the solidsurfacecurvature, as are present in the formof corners on the capillary surfaces, havestrong influences on liquid penetration through their pinning effects and also theirinteractions with local geometry. The microtopography can therefore, accelerate,decelerate and, in some cases, even stop the liquid penetration into random porousmedia.

  • 297.
    Wong, Winnie
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    A Hybrid Pixel Detector ASIC with Energy Binning for Real-Time, Spectroscopic Dose Measurements2012Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Hybrid pixel detectors have been demonstrated to provide excellent quality detection of ionising photon radiation, particularly in X-ray imaging. Recently, there has been interest in developing a hybrid pixel detector specifically for photon dosimetry. This thesis is on the design, implementation, and preliminary characterisation of the Dosepix readout chip.

    Dosepix has 256 square pixels of 220 mm side-length, constituting 12.4 mm2 of photo-sensitive area per detector. The combination of multiple pixels provides many parallel processors with limited input flux, resulting in a radiation dose monitor which can continuously record data and provide a real-time report on personal dose equivalent. Energy measurements are obtained by measuring the time over threshold of each photon and a state machine in the pixel sorts the detected photon event into appropriate energy bins. Each pixel contains 16 digital thresholds with 16 registers to store the associated energy bins. Preliminary measurements of Dosepix chips bump bonded to silicon sensors show very promising results. The pixel has a frontend noise of 120 e-. In low power mode, each chip consumes 15 mW, permitting its use in a portable, battery-powered system. Direct time over threshold output from the hybrid pixel detector assembly reveal distinctive photo-peaks correctly identifying the nature of incident photons, and verification measurements indicate that the pixel binning state machines accurately categorise charge spectra. Personal dose equivalent reconstruction using this data has a flat response for a large range of photon energies and personal dose equivalent rates.

  • 298.
    Xue, Shang
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Alternating Coding and its Decoder Architectures for Unary-Prefixed Codes2005Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The entropy coding of high peak, heavy-tailed probability distributions such as the Laplacian, Cauchy, and generalized Gaussian have been a topic of interest because they are able to provide good models for data in many coding systems, especially in image and video coding systems. This thesis studies the entropy coding of such high peak, heavy-tailed probability distributions. By summarizing the encoding of such distributions under the concept “Unary Prefixed Codes” (UPC), the thesis depicts the encoding via a different approach. By extending the concept of UPC, the thesis proposes a universally applicable coding algorithm “Unary Prefixed Huffman” (UPH) that could be applied to both finite and infinite sources. The code set resulting from the UPH algorithm has a coding efficiency which is upper-bounded by entropy + 2 given that the entropy is finite, and is able to provide sub-optimal encoding of the sources studied in the thesis. The thesis also proposes several different variations of UPCs that are simple in structure yet efficient for use for several variations of the high peak, heavy-tailed distributions that are commonly found in image and video coding systems. By applying the concept of the UPC, the thesis further proposes a coding method named the “Alternating Coding” (ALT) method. The ALT coding provides a coding pattern that is different from the conventional method which enables the extraction of special properties of the UPCs. Using the extraction of the special property of the UPCs, decoding could be greatly simplified and parallel decoding could be a possibility. Moreover, for the highly structured UPCs that are widely used in image and video coding systems, the ALT coding enables an error resiliency mechanism to be applied, which helps to improve the error tolerance of these UPC packets to a significant extent. Simulations and actual application results of the ALT coding are discussed in the thesis. By applying the ALT coding, the hardware architecture of the decoder changes accordingly. The ALT decoder is different to the conventional variable length decoders that have been applied in the decoding of UPCs, as it is able to utilize the special properties of the UPCs and thus simplify the decoder architecture. As shown in the thesis, the ALT decoders are smaller in size, faster in speed and consume much less power compared to the conventional decoders. This is particularly true for those highly structured UPCs that are commonly used in image and video coding systems. Actual realizations of several ALT decoders are discussed in the thesis, and comparisons are made to the conventional decoders. The improvements are shown to be very evident.

  • 299.
    Yahaya, Ismail
    Mittuniversitetet, Fakulteten för humanvetenskap, Avdelningen för hälsovetenskap.
    Childhood Sexual Abuse Against Girls in Sub-Saharan Africa: Individual and Contextual Risk Factors2014Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Background and objectives: Childhood sexual abuse (CSA) is a substantial public health and human rights problem, as well as a growing concern in sub-Saharan Africa (SSA). It has both short and long term effects on girls: physical and psychological, including negative sexual outcomes. Up to one-third of adolescent girls report their first sexual experience as being forced. Despite growing evidence supporting a link between contextual factors and violence, no studies have investigated the connection between CSA and contextual factors. It is therefore important to identify the extent of CSA and understand factors associated with it in SSA in order to develop interventions aimed to address the scale of the problem.

    Aim: The overall aim of this thesis is to assess the individual and contextual factors associated with CSA. In addition, the thesis aims to quantify the magnitude of CSA and describe the factors associated with CSA among women from SSA (Study I). This thesis also examines the independent contribution of individual and community socio-economic status on CSA (Study II). Moreover, it scrutinises the effect of social disorganisation on CSA (Study III) and explores the relationship between CSA and sexual risk behaviours as well as potential mediators (Study IV).

    Methods: This thesis used the Demographic and Health Survey (DHS) datasets conducted between 2006 and 2008 from six SSA countries. The thesis used multiple logistic regression models to describe and explore factors associated with CSA among 69,977 women (Study I).  It used multivariable multilevel logistic regression analysis to explore the effect of contextual level variables (neighbourhood socio-economic status) on CSA among 6,351 girls (Study II). Neighbourhood socio-economic status was operationalized with a principal component analysis using the proportion of respondents who were unemployed, illiterates, living below poverty level and rural residents. Study III applied multivariable multilevel logistic regression analysis on 6,351 girls and considered five measures of social disorganisation at the community level: neighbourhood poverty, female-headed households, residential mobility, place of residence, population density, and ethnic diversity. In study IV, 12,800 women from the Nigerian DHS were used. Structural equation modelling was applied using a two-step approach. The first step used a confirmatory factor analysis to develop an acceptable measurement model while the second step involved modifying the measurement model to represent the postulated causal model framework.

    Results: In study I, the reported prevalence of CSA ranged from 0.3% in Liberia to 4.3% in Zambia when the prevalence was based on all respondents aged between 15 and 49 years and who were present during the survey. None of the socio-economic factors were associated with CSA. In study II, where the data was restricted to permanent residents aged between 15 and 18 years, the prevalence ranged between 1.04% in Liberia to 5.8% in Zambia. At the individual level, there was no significant association between CSA and wealth status while at the community level, there was no significant association between CSA and socio-economic position. However, 22% of the variation in CSA was attributed to the community level factors. In study III, there was significant variation in the odds of reporting CSA across the communities, with community level factors accounting for 18% of the variation. In addition, respondents from communities with a high family disruption rate were 57% more likely to have reported sexual abuse in childhood. Study IV showed that there was a significant association between CSA and sexual risk behaviours and the association was mediated by alcohol and cigarette use.

    Conclusions: The study provides evidence that adolescents in the same community were subjected to common contextual influences. It also highlighted the significance of mediators in the relationship between CSA and sexual risk behaviours. It is therefore important that effective preventive strategies are developed and implemented that will cut across all socio-economic spheres in a context that both permits and encourages disclosure as well as identifying predisposing circumstances for recurrence.

  • 300.
    Zasadowski, Dariusz
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik. Mittuniversitetet.
    Selective Separation Of Wood Components In Internal Process Waters Originating From Mechanical Pulping2014Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Dissolved and Colloidal substances (DSC) and metals are released from woodduring thermomechanical pulp (TMP) production. These components have atendency to accumulate in process waters, as the water circulation systems inintegrated paper mills are closed. Disturbances such as pitch depositions in thepaper machine (pitch problems), specks in the paper, decreased wet and drystrength, interference with cationic process chemicals, and impaired sheetbrightness and friction properties appear when DSC are present. Transition metalions such as manganese results in higher consumption of bleaching chemicals(hydrogen peroxide) and lowers the optical quality of the final product, andaddition of complexing agents, such as EDTA or DTPA, to prevent this is needed.The never ending trends to decrease water consumption and increase processefficiency in pulp and paper production emphasizes that it is very important bothto know the effects of wood substances on pulping and papermaking and to beable to remove them in an efficient way. From a biorefinery point of view, DSCcomponents can be promising renewable raw materials for biofuels, bio‐basedchemicals and materials.In this thesis, a new approach using induced air flotation (IAF) without a cationicpolyelectrolyte addition for the removal of pitch and metal ions from mechanicalpulp mill process waters is presented. The induced air flotation of different processwaters is facilitated by the addition of a chelating surfactant and different foamingagents. The influence of the pH value, temperature and foaming agentconcentration on the flotation efficiency has been investigated. The investigations

    presented show that the disturbing components can be removed from TMP presswater to a high extent. A 90% decrease in turbidity and a 91% removal of lipophilicextractives (i.e. resin and fatty acids, triglycerides, sterols and steryl esters) fromunbleached and bleached TMP process water can be obtained by addition of acationic surfactant as foaming agent during flotation. Lower amount of foamingagent is needed to purify efficiently bleached TMP process water, than unbleached.Additionally, fibres located in TMP press water are not removed with the foamfraction but purified. A retained concentration of hydrophilic extractives (i.e.hemicelluloses and lignans) in the process water indicates that the flotation isselective. Moreover, by introduction of a new recoverable surface activecomplexing agent, a chelating surfactant, manganese ions in the form of chelatescan be successfully removed from the pulp fibres and separated from the processwater in the same flotation process. Furthermore, from the purified unbleachedTMP process water a 90% recovery of dissolved hemicelluloses by anti‐solventprecipitation was obtained.The findings presented above indicate new possibilities for the internal watercleaning stage to decrease DSC emissions to recipient and for recovery of valuableraw materials from purified process water if flotation technology is applied in anintegrated mechanical pulp mill.

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