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  • 51.
    Brunnström, Kjell
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems. NetLab: Visual Media Quality, Acreo Swedish ICT AB, SE-16440 Kista, Sweden.
    Ananth, I. V.
    NetLab: Visual Media Quality, Acreo Swedish ICT AB, SE-16440 Kista, Sweden.
    Hedberg, C.
    NetLab: Visual Media Quality, Acreo Swedish ICT AB, SE-16440 Kista, Sweden.
    Wang, Kun
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems. NetLab: Visual Media Quality, Acreo Swedish ICT AB, SE-16440 Kista, Sweden.
    Andrén, B.
    NetLab: Visual Media Quality, Acreo Swedish ICT AB, SE-16440 Kista, Sweden.
    Barkowsky, M.
    Dept. of Image and Video Communication, IRCCyN, University of Nantes, France .
    Comparison between different rating scales for 3D TV2013In: SID Symposium Digest of Technical Papers, 2013, Vol. 44, no 1, p. 509-512Conference paper (Refereed)
    Abstract [en]

    Stereoscopic 3D viewing experience has been studied quite intensively recently, but still the subjective test methods have not yet been settled. It has become clear that the 3D viewing experience cannot easily be described by just one scale. This paper describes a study where three different rating scales (Quality, Discomfort and Presence) are compared in a subjective test, combined with two viewing distances. The results shows that in a stereoscopic 3D video quality test targeting mainly coding distortions one scale such as video quality could be sufficient. © 2013 Society for Information Display.

  • 52.
    Brunnström, Kjell
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems. Acreo Swedish ICT AB, Kista, Sweden.
    Tavakoli, S.
    Universidad Politécnica de Madrid, Madrid, Spain.
    Søgaard, J.
    Technical University of Denmark, Kgs Lyngby, Denmark .
    Compensating for Type-I errors in video quality assessment2015In: 2015 7th International Workshop on Quality of Multimedia Experience, QoMEX 2015, 2015, p. Art. no. 7148080-Conference paper (Refereed)
    Abstract [en]

    This paper analyzes the impact on compensating for Type-I errors in video quality assessment. A Type-I error is to incorrectly conclude that there is an effect. The risk increases with the number of comparisons that are performed in statistical tests. Type-I errors are an issue often neglected in Quality of Experience and video quality assessment analysis. Examples are given for the analysis of subjective experiments and the evaluation of objective metrics by correlation. © 2015 IEEE.

  • 53.
    Brunnström, Kjell
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems. Dept. of NetLab, Visual Media Quality, Acreo Swedish ICT AB, Sweden .
    Wang, Kun
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science. Dept. of NetLab, Visual Media Quality, Acreo Swedish ICT AB, Sweden .
    Andrén, B.
    Dept. of NetLab, Visual Media Quality, Acreo Swedish ICT AB, Sweden .
    Simulator Sickness analysis of 3D video viewing on passive 3D TV2013In: Proceedings of SPIE - The International Society for Optical Engineering, 2013, p. Art. no. 864802-Conference paper (Refereed)
    Abstract [en]

    The MPEG 3DV project is working on the next generation video encoding standard and in this process a call for proposal of encoding algorithms was issued. To evaluate these algorithm a large scale subjective test was performed involving Laboratories all over the world. For the participating Labs it was optional to administer a slightly modified Simulator Sickness Questionnaire (SSQ) from Kennedy et al (1993) before and after the test. Here we report the results from one Lab (Acreo) located in Sweden. The videos were shown on a 46 inch film pattern retarder 3D TV, where the viewers were using polarized passive eye-glasses to view the stereoscopic 3D video content. There were 68 viewers participating in this investigation in ages ranges from 16 to 72, with one third females. The questionnaire was filled in before and after the test, with a viewing time ranging between 30 min to about one and half hour, which is comparable to a feature length movie. The SSQ consists of 16 different symptoms that have been identified as important for indicating simulator sickness. When analyzing the individual symptoms it was found that Fatigue, Eye-strain, Difficulty Focusing and Difficulty Concentrating were significantly worse after than before. SSQ was also analyzed according to the model suggested by Kennedy et al (1993). All in all this investigation shows a statistically significant increase in symptoms after viewing 3D video especially related to visual or Oculomotor system.

  • 54.
    Brunnström, Kjell
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems. Acreo Swedish ICT AB, Kista, Sweden.
    Wang, Kun
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems. Acreo Swedish ICT AB, Kista, Sweden.
    Andrén, Börje
    Acreo Swedish ICT AB, Kista, Sweden.
    Kulyk, Valentin
    Ericsson Research, Sweden.
    Tavakoli, Samira
    Universidad Politécnica de Madrid, Spain.
    Hedberg, Christer
    Acreo Swedish ICT AB, Kista, Sweden.
    Ananth, Indirajith Vijai
    Acreo Swedish ICT AB, Kista, Sweden.
    Hussein, Mahir
    Acreo Swedish ICT AB, Kista, Sweden.
    Folkesson, Mats
    Ericsson Research, Sweden.
    Barkowsky, Marcus
    Acreo Swedish ICT AB, Kista, Sweden.
    3D Video Quality of Experience - Influence of Scale and Crosstalk Invited2014In: Proceedings of the 8th International Workshop on Video Processing and Quality Metrics for Consumer Electronics VPQM-2014, Scottsdale, AZ, USA, 2014Conference paper (Refereed)
    Abstract [en]

    This paper gives an overview of three recent studies by the authors on the topic of 3D video Quality of Experience (QoE). Two of studies [1,2] investigated different psychological dimension that may be needed for describing 3D video QoE and the third the visibility and annoyance of crosstalk[3]. The results shows that the video quality scale could be sufficient for evaluating S3D video experience for coding and spatial resolution reduction distortions. It was also confirmed that with a more complex mixture of degradations more than one scale should be used to capture the QoE in these cases. The study found a linear relationship between the perceived crosstalk and the amount of crosstalk.

  • 55.
    Burgos, Peter
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Storsten, Julia
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Vulnerability in a cyberattack: How DoS affects Swedish government authorities2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With a growing development of technologies and the fact that many companies implements online services, an interruption in such service could cause problems for any kind of user by exploiting the vulnerabilities in these systems. The Swedish Armed Forces (SwAF) indicates that the development of the defensive ability must continue, since the vulnerability of the cyberenvironment becomes a greater interest for adversaries. A denial of service can create panic by e.g. force resources to look into the ongoing attack minimizing the awareness of the protection of other systems. Known attacking tools and statistics are presented in this thesis, but the scope is to generate a framework. The main aim is to look into the Swedish government authorities and give an insight of how a possible path for an increased resilience against a modern distributed denial of service attack could be and at the same time expand the knowledge and give a base for developing more secure systems. This thesis consists of a survey and simulations of network traffic behaviors in order to categorize and give a framework for a small, middle and large sized authority. The result shows that a small sized authority has a risk of 47% in not being able to survive an attack, while a middle sized authority only would have 17% as dangerous risk, since that is the risk of having attacks exceeding 60 Gbit/s. A large sized authority is defined by having a capacity of 100 Gbit/s. Therefore, an increased resilience is by exceeding 60 Gbit/s showing that 60% of the authorities within this thesis are prepared against a modern distributed denial of service attack. If an attack succeeds, the authorities are at greater risk to not be able to communicate externally and reach out to the society as impact.

  • 56.
    Bygdeson, Andreas
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Cartographer: En kartbaserad friluftsapplikation2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Målet med det här arbetet har varit att utveckla en friluftsapplikation för människor som rör sig i skog och mark antingen i arbetet eller i privatlivet. Med syfte att låta de skapa och placera ut markörer på en karta med aktivt uppdaterande gps positionering. För att uppnå detta har Google Maps använts som gränssnitt för att hämta och hantera kartinformation och en applikation har designats i flödesscheman utefter kravspecifikationen och i enlighet med Jacob Nielsens användbarhetsprinciper. Hallway test metoden har använts för att utvärdera hur väl användbarhetsdesignen har uppnått sina mål. Applikationen har sedan konstruerats i Java och Android Studio mot Androids mobila plattform. Utvecklingen har följt den planerade designen och uppnått samtliga konkreta mål som specificerades och i synnerhet användbarhetsmålen. Flera funktionella mål har identifierats att kunna optimeras ytterligare och en rad förslag på vidareutveckling av applikationen har tagits fram för eventuella framtida arbeten.

  • 57.
    Chalak, Arian
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Effekter av lokalkännedom för larmbetjäning på SOS Alarm Sverige AB: En studie om övergången till nationell mottagning av 112 anrop och dess inverkan på samtalstiden2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    SOS Alarm has had an increasingly number of urgent calls to the number 112. With that come high demands on errand handling within the company. To measure and follow the effects of national reception of urgent 112 calls is therefore an important priority for 2016. The Purpose of this study is to investigate if the call time is longer with a national operator with relationship to a local operator. That is achievable by studying the mean value of the call time for local and national reception of calls. The goal is by statistical analysis and hypothesis testing study if the operator’s localization and distance to the caller effects call time. The result shows that there is a statistical significant difference between mean value of call time for national and local reception, with national reception being longer. The lognormal distribution is non-linear, therefore the difference between the call times before the transformation is not being analyzed. The conclusion of this study is that that local knowledge has a significant influence on call time, where mean call time is longer for national reception. Provided that there is no difference in call time between the call types, it is further discussed in closing discussions.

  • 58.
    Chen, Nan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    An IEEE 802.15.4 Packet Error Classification Algorithm: Discriminating Between Multipath Fading and Attenuation and WLAN2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In wireless sensor networks, communications are usually destroyed by signal attenuation, multipath fading and different kinds of interferences like WLAN and microwave oven interference. In order to build a stable wireless communication system, reactions like retransmission mechanisms are necessary. Since the way we must react to interference is different from the way we react to multipathfading and attenuation, the retransmission mechanism should be adjusted in different ways under those different cicumstances. Under this condition, channel diagnostics for discriminating the causes that corrupt the packets between multipath fading and attenuation (MFA) and WLAN interference are imperative. This paper presents a frame bit error rate (F-BER) regulated algorithm based on a joint RSSI-LQI classifier that may correctly diagnose the channel status. This discriminator is implemented on MicaZ sensor devices equipped with CC2420 transceivers. This discriminator is able to improve the accuracy to 91%. Although we need to wait for 2 or 3 necessary packets to make a decision, higher stability and reliability are presented when operating this discriminator.

  • 59.
    Christopher, Axelsson
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Fernando, Sanchez
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Benefits of cost engineering enabled by value stream mappings: Learnings from a die casting value chain with multiple suppliers2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    It has always been an advantage to reduce and know the supplier´s manufacturing costs when a customer negotiates with the supplier. Now more than ever, when the competition is getting harder, it is necessary to use lean to remove all non-adding value to the final product and reduce all possible costs. This paper is about the benefits of cost engineering enabled by value stream mapping that die casting customers can obtain towards suppliers. The research shows how lean and value stream mapping can be used to identify and remove certain wastes at supplier’s manufacturing to reduce costs.  A multiple supplier production permits the costumer to identify wastes and find improvements in an efficient manner.   In addition, cost engineering can be enabled by value stream mapping to estimate costs in current and future production after the application of lean to obtain real fact of production costs. The cost estimation done using real information of production can be used to gain bargaining power, in contrast to actual strategies where the costumer negotiates price by comparing diverse suppliers with different production conditions. The proposed methodology combines value stream mapping and cost estimation to take advantage of the benefits of cost reduction and cost estimation to generate savings.

  • 60.
    Chukala, Sileshi
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    A Move Towards Practicability: Context Information and User Profile Management for the SensibleThings Platform2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Achievements in academia and industry indicate a move towards the creation of a giant smart system including objects of different sizes, shapes, and purposes where the Internet will be so diverse and more resourceful with the incorporation of different smart devices. Mid Swe-den University took a first step towards providing an appropriate plat-form for Internet of Things applications known as SensibleThings for the emerging intercommunication of “objects”, called Internet of Things. The SensibleThings platform has produced components for sharing sensor-based context information on the Internet, in order to enable Internet of Things applications. In this thesis the plan was to contribute to filling the gap between the IoT and developers in academia as well as in the industries. The aim of the project was to create basic functionality to enable users to find new interesting users on the IoT and prioritize existing users. To this end context information and user profile man-agement is proposed and presented. Furthermore, a comparison be-tween the platform with the proposed extension as well as without was compared and examined.

  • 61.
    Cui, Qin
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    TDMA-based Routing Protocol in Industrial Wireless Sensor Networks2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 62.
    Dadash Pour Khalkhali, Mohammad Mehdi
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    User Experience Enhancement in 3D Video Conferencing2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    3D video conferencing is continuously evolving to make the visual experience realistic. The main advantage of 3D video conferencing deals with the addition of depth perception which enhances the user experience. The configuration of capturing and rendering equipments and the location of scene objects play an essential role in the quality of the user experience. An incorrect configuration of equipment parameters or an inconsistent distribution of scene components could cause an uncomfortable user experience, yielding in user sickness and dizziness.

    The aim of this thesis is therefore to provide the tools and methods to assure a comfortable user experience when using Ericsson’s stereoscopic 3D video conferencing system. To achieve this goal, an investigation on the capturing and rendering systems has been performed to identify possible conflicts. This investigation has shown that accommodation-convergence rivalry, comfortable viewing range and stereo framing violation are the major sources of user discomfort in 3D video conferencing.

    An algorithm for continuous analysis of produced stereoscopic content has been proposed. In particular, it detects wrong equipment configuration and problematic content in real time by means of automatic adjustments or user interaction, either at initiation phase or during the call session at capturing side. To validate and evaluate the efficiency of the implemented solution, a subjective test with participation of the 3D experts has been carried out. It has been shown that the proposed solution can detect targeted problems with high accuracy and apply corrective actions. It is important to note that manual solutions are not immune to problems. Nevertheless, it has also been shown that automatic solutions can considerably compensate manual methods inconsistency and provide a comfortable user experience. 

  • 63.
    Dahlström, Jesper
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Enhetsoberoende GUI av larmapplikation2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The company Attendit have been developing the system product NetAlert™ since 2006.  NetAlert™ has clients for Android, Win 32, and iOS. The product is an alarm system for personal safety which uses a serverbackend with which all clients communicate through an encrypted socket in real-time. The goal of this project was to develop NetAlert™ further, to get a responsive and user-friendly interface that anyone can use, regardless of technical competence. The poll was conducted by means of a questionnaire that users answered. During the development stage, the survey has been in mind, to obtain an application that users find easy to use. Unfortunately, I did not have time to finish the application due there were many hours of troubleshooting, bug fixes and the such, so the time was not quite enough, but I conclude that my user interface is easy to use, visually appealing, and it is suitable for all age groups.

  • 64.
    Dalin, Rolf
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Bostedt, Göran
    Mid Sweden University, Faculty of Human Sciences, Department of Education.
    Blusi, Madeleine
    Ungdomar i Kramfors - åsikter och attityder: LUPP - lokal uppföljning av ungdomspolitiken2013Report (Other academic)
  • 65.
    Dalin, Rolf
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Bostedt, Göran
    Mid Sweden University, Faculty of Human Sciences, Department of Education.
    Blusi, Madeleine
    Ungdomar i Sollefteå - åsikter och attityder: LUPP - Lokal uppföljning av ungdomspolitiken2013Report (Other academic)
  • 66.
    Damghanian, Mitra
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    The Sampling Pattern Cube: A Framework for Representation and Evaluation of Plenoptic Capturing Systems2013Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Digital cameras have already entered our everyday life. Rapid technological advances have made it easier and cheaper to develop new cameras with unconventional structures. The plenoptic camera is one of the new devices which can capture the light information which is then able to be processed for applications such as focus adjustments. The high level camera properties, such as the spatial or angular resolution are required to evaluate and compare plenoptic cameras. With complex camera structures that introduce trade-offs between various high level camera properties, it is no longer straightforward to describe and extract these properties. Proper models, methods and metrics with the desired level of details are beneficial to describe and evaluate plenoptic camera properties.

    This thesis attempts to describe and evaluate camera properties using a model based representation of plenoptic capturing systems in favour of a unified language. The SPC model is proposed and it describes which light samples from the scene are captured by the camera system. Light samples in the SPC model carry the ray and focus information of the capturing setup. To demonstrate the capabilities of the introduced model, property extractors for lateral resolution are defined and evaluated. The lateral resolution values obtained from the introduced model are compared with the results from the ray-based model and the ground truth data. The knowledge about how to generate and visualize the proposed model and how to extract the camera properties from the model based representation of the capturing system is collated to form the SPC framework.

    The main outcomes of the thesis can be summarized in the following points: A model based representation of the light sampling behaviour of the plenoptic capturing system is introduced, which incorporates the focus information as well as the ray information. A framework is developed to generate the SPC model and to extract high level properties of the plenoptic capturing system. Results confirm that the SPC model is capable of describing the light sampling behaviour of the capturing system, and that the SPC framework is capable of extracting high level camera properties with a higher descriptive level as compared to the ray-based model. The results from the proposed model compete with those from the more elaborate wave optics model in the ranges that wave nature of the light is not dominant. The outcome of the thesis can benefit design, evaluation and comparison of the complex capturing systems.

  • 67.
    Damghanian, Mitra
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Olsson, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Depth and Angular Resolution in Plenoptic Cameras2015In: 2015 IEEE International Conference On Image Processing (ICIP), September 2015, IEEE, 2015, p. 3044-3048, article id 7351362Conference paper (Refereed)
    Abstract [en]

    We present a model-based approach to extract the depth and angular resolution in a plenoptic camera. Obtained results for the depth and angular resolution are validated against Zemax ray tracing results. The provided model-based approach gives the location and number of the resolvable depth planes in a plenoptic camera as well as the angular resolution with regards to disparity in pixels. The provided model-based approach is straightforward compared to practical measurements and can reflect on the plenoptic camera parameters such as the microlens f-number in contrast with the principal-ray-model approach. Easy and accurate quantification of different resolution terms forms the basis for designing the capturing setup and choosing a reasonable system configuration for plenoptic cameras. Results from this work will accelerate customization of the plenoptic cameras for particular applications without the need for expensive measurements.

  • 68.
    Damghanian, Mitra
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Olsson, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Performance analysis in Lytro camera: Empirical and model based approaches to assess refocusing quality2014In: ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings, IEEE conference proceedings, 2014, p. 559-563Conference paper (Refereed)
    Abstract [en]

    In this paper we investigate the performance of Lytro camera in terms of its refocusing quality. The refocusing quality of the camera is related to the spatial resolution and the depth of field as the contributing parameters. We quantify the spatial resolution profile as a function of depth using empirical and model based approaches. The depth of field is then determined by thresholding the spatial resolution profile. In the model based approach, the previously proposed sampling pattern cube (SPC) model for representation and evaluation of the plenoptic capturing systems is utilized. For the experimental resolution measurements, camera evaluation results are extracted from images rendered by the Lytro full reconstruction rendering method. Results from both the empirical and model based approaches assess the refocusing quality of the Lytro camera consistently, highlighting the usability of the model based approaches for performance analysis of complex capturing systems.

  • 69.
    Damghanian, Mitra
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Olsson, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Erdmann, Arne
    Raytrix Gmbh.
    Perwass, Christian
    Raytrix Gmbh.
    Spatial resolution in a multi-focus plenoptic camera2014In: IEEE International Conference on Image Processing, ICIP 2014, IEEE conference proceedings, 2014, p. 1932-1936, article id 7025387Conference paper (Refereed)
    Abstract [en]

    Evaluation of the state of the art plenoptic cameras is necessary for design and application purposes. In this work, spatial resolution is investigated in a multi-focus plenoptic camera using two approaches: empirical and model-based. The Raytrix R29 plenoptic camera is studied which utilizes three types of micro lenses with different focal lengths in a hexagonal array structure to increase the depth of field. The modelbased approach utilizes the previously proposed sampling pattern cube (SPC) model for representation and evaluation of the plenoptic capturing systems. For the experimental resolution measurements, spatial resolution values are extracted from images reconstructed by the provided Raytrix reconstruction method. Both the measurement and the SPC model based approaches demonstrate a gradual variation of the resolution values in a wide depth range for the multi focus R29 camera. Moreover, the good agreement between the results from the model-based approach and those from the empirical approach confirms suitability of the SPC model in evaluating high-level camera parameters such as the spatial resolution in a complex capturing system as R29 multi-focus plenoptic camera.

  • 70.
    Damghanian, Mitra
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Olsson, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Navarro Fructuoso, Hector
    Department of Optics, University of Valencia, Spain.
    Martinez Corral, Manuel
    Department of Optics, University of Valencia, Spain.
    Investigating the lateral resolution in a plenoptic capturing system using the SPC model2013In: Proceedings of SPIE - The International Society for Optical Engineering: Digital photography IX, SPIE - International Society for Optical Engineering, 2013, p. 86600T-Conference paper (Refereed)
    Abstract [en]

    Complex multidimensional capturing setups such as plenoptic cameras (PC) introduce a trade-off between various system properties. Consequently, established capturing properties, like image resolution, need to be described thoroughly for these systems. Therefore models and metrics that assist exploring and formulating this trade-off are highly beneficial for studying as well as designing of complex capturing systems. This work demonstrates the capability of our previously proposed sampling pattern cube (SPC) model to extract the lateral resolution for plenoptic capturing systems. The SPC carries both ray information as well as focal properties of the capturing system it models. The proposed operator extracts the lateral resolution from the SPC model throughout an arbitrary number of depth planes giving a depth-resolution profile. This operator utilizes focal properties of the capturing system as well as the geometrical distribution of the light containers which are the elements in the SPC model. We have validated the lateral resolution operator for different capturing setups by comparing the results with those from Monte Carlo numerical simulations based on the wave optics model. The lateral resolution predicted by the SPC model agrees with the results from the more complex wave optics model better than both the ray based model and our previously proposed lateral resolution operator. This agreement strengthens the conclusion that the SPC fills the gap between ray-based models and the real system performance, by including the focal information of the system as a model parameter. The SPC is proven a simple yet efficient model for extracting the lateral resolution as a high-level property of complex plenoptic capturing systems.

  • 71.
    Danielson, Mats
    et al.
    Dept. of Computer and Systems Sciences, Stockholm University.
    Ekenberg, Love
    Dept. of Computer and Systems Sciences, Stockholm University.
    Larsson, Aron
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Riabacke, Mona
    Dept. of Computer and Systems Sciences, Stockholm University.
    Weighting Under Ambiguous Preferences and Imprecise Differences in a Cardinal Rank Ordering Process2013In: International Journal of Computational Intelligence Systems, ISSN 1875-6883, Vol. 7, no 1, p. 105-112Article in journal (Refereed)
    Abstract [en]

    The limited amount of good tools for supporting elicitation of preference information in multi-criteria decision analysis (MCDA) causes practical problem. In our experiences, this can be remedied by allowing more relaxed input statements from decision-makers, causing the elicitation process to be less cognitively demanding. Furthermore, it should not be too time consuming and must be able to actually use of the information the decision-maker is able to supply. In this paper, we propose a useful weight elicitation method for MAVT/MAUT decision making, which builds on the ideas of rank-order methods, but increases the precision by adding numerically imprecise cardinal information as well.

  • 72.
    De Moor, K
    et al.
    NTNU, Trondheim, Norway.
    Andrén, B
    Acreo Swedish ICTAB, Kista, Sweden.
    Yi, G
    Acreo Swedish ICTAB, Kista, Sweden.
    Brunnström, Kjell
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems. Acreo Swedish ICTAB, Kista, Sweden.
    Wang, K
    Acreo Swedish ICTAB, Kista, Sweden.
    Drott, A
    Volvo Cars AB, Gothenburg, Sweden.
    Hermann, D
    Volvo Cars AB, Gothenburg, Sweden.
    Influence of high ambient illuminance and display luminance on readability and subjective preference2015In: Proceedings of SPIE - The International Society for Optical Engineering / [ed] Rogowitz, B., Pappas, T. N., and de Ridder, H., Bellingham, WA, USA: SPIE - International Society for Optical Engineering, 2015, Vol. 9394, p. Art. no. 93941E-Conference paper (Refereed)
    Abstract [en]

    Many devices, such as tablets, smartphones, notebooks, fixed and portable navigation systems are used on a (nearly) daily basis, both in in- and outdoor environments. It is often argued that contextual factors, such as the ambient illuminance in relation to characteristics of the display (e.g., surface treatment, screen reflectance, display luminance...) may have a strong influence on the use of such devices and corresponding user experiences. However, the current understanding of these influence factors is still rather limited. In this work, we therefore focus in particular on the impact of lighting and display luminance on readability, visual performance, subjective experience and preference. A controlled lab study (N=18) with a within-subjects design was performed to evaluate two car displays (one glossy and one matte display) in conditions that simulate bright outdoor lighting conditions. Four ambient luminance levels and three display luminance settings were combined into 7 experimental conditions. More concretely, we investigated for each display: (1) whether and how readability and visual performance varied with the different combinations of ambient luminance and display luminance and (2) whether and how they influenced the subjective experience (through self-reported valence, annoyance, visual fatigue) and preference. The results indicate a limited, yet negative influence of increased ambient luminance and reduced contrast on visual performance and readability for both displays. Similarly, we found that the self-reported valence decreases and annoyance and visual fatigue increase as the contrast ratio decreases and ambient luminance increases. Overall, the impact is clearer for the matte display than for the glossy display.

  • 73.
    Dibo, Alexandra
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Implementering av lean i serviceföretag: En analys av tolkningen och implementeringen av lean på Coor Service Management2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Toyota is one of the world's most successful companies, the success has come because the company balances the employees' role in an organiza-tional culture that expects and values continuous improvement, with a technical system that focuses on strong value-added "flow". Toyota is working to provide quality and bases this work on the tools and meth-ods of quality improvement which along with Toyota's philosophy forms the lean manufacturing. The investigation in this work has been to analyze Coor Service Management's interpretation and implementa-tion of Lean from The Toyota Way. The Toyota Way is according to Jeffrey K. Liker 14 principles for an organization to become lean and is based on many years of studies of Toyota. Because there is currently no universally accepted definition of lean the implementation of the concept is problematized. Coor Service Management is a service com-pany and studies of the implementation of lean in the service environ-ment are almost non-existent. This, together with the problem of defin-ing lean has been the basis for this work. The survey was conducted through a literature review, a number of scientific articles that con-cerned the subject, interviews, observation and participation in the physical workplace, as well as value flow mapping and triangulation. The result shows that it is possible to apply the basic principles of the Toyota Way in service companies but that lean cannot be seen as a specific concept, but as a collection of general principles that various actors interpret and apply in different ways.

  • 74.
    Dima, Elijs
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Development of interactive entertainment system for Din Tur buses: Håll Platsen2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Public transport organizations, such as Din Tur, require affordable modern solutions to improve their public image and passenger satisfaction. An easy way to create positive associations in people is to provide either useful services or, preferably, entertainment. This report covers the design, development and evaluation of an entertainment system – consisting of a smartphone game, a cloud-hosted backend, and a supporting on-bus hardware system – with the objective of making Din Tur's bus service seem more modern and appealing. The smartphone game, “Håll Platsen”, is developed in Unity game engine, focuses on providing brief entertainment during bus commutes, and incorporates gamification design elements. The Python-based back-end resides in Google's App Engine and Datastore platforms, and provides a unified virtual game environment enabling player cooperation and competition. The prototype on-bus hardware system uses the Raspberry Pi as a Light-Emitting Diode control system to supply real-world feedback of the game's virtual environment. The systems incorporate real-world busstop positioning, player location, online mapping services, team location-control mechanics, reflex-based minigames, player progression mechanics, and mobile-focused design. The resulting system can be useful in estimating public response to non-standard “smart” promotion methods, the use of games to improve everyday routines (i.e. commuting), and serve as a basis for further research in human & smart-technology interaction.

  • 75.
    Dima, Elijs
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Olsson, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Assessment of Multi-Camera Calibration Algorithms for Two-Dimensional Camera Arrays Relative to Ground Truth Position and Direction2016In: 3DTV-Conference, IEEE Computer Society, 2016, article id 7548887Conference paper (Refereed)
    Abstract [en]

    Camera calibration methods are commonly evaluated on cumulative reprojection error metrics, on disparate one-dimensional da-tasets. To evaluate calibration of cameras in two-dimensional arrays, assessments need to be made on two-dimensional datasets with constraints on camera parameters. In this study, accuracy of several multi-camera calibration methods has been evaluated on camera parameters that are affecting view projection the most. As input data, we used a 15-viewpoint two-dimensional dataset with intrinsic and extrinsic parameter constraints and extrinsic ground truth. The assessment showed that self-calibration methods using structure-from-motion reach equal intrinsic and extrinsic parameter estimation accuracy with standard checkerboard calibration algorithm, and surpass a well-known self-calibration toolbox, BlueCCal. These results show that self-calibration is a viable approach to calibrating two-dimensional camera arrays, but improvements to state-of-art multi-camera feature matching are necessary to make BlueCCal as accurate as other self-calibration methods for two-dimensional camera arrays.

  • 76.
    Dobslaw, Felix
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Zhang, Tinting
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Challenges for the use of data aggregation in industrial Wireless Sensor Networks2015In: IEEE International Conference on Automation Science and Engineering, IEEE Computer Society, 2015, p. 138-144Conference paper (Refereed)
    Abstract [en]

    The provision of quality of service for Wireless Sensor Networks is more relevant than ever now where wireless solutions with their flexibility advantages are considered for the extension/substitution of wired networks for a multitude of industrial applications. Scheduling algorithms that give end-to-end guarantees for both reliability and latency exist, but according to recent investigations is the achieved quality of service insufficient for most control applications. Data aggregation is an effective tool to significantly improve on end-to-end contention and energy efficiency compared to single packet transmissions. In practice, though, it is not extensively used for process data processing on the MAC layer. In this paper, we outline the challenges for the use of data aggregation in Industrial Wireless Sensor Networks. We further extend SchedEx, a reliability-aware scheduling algorithm extension, for packet aggregation. Our simulations for scheduling algorithms from the literature show its great potential for industrial applications. Features for the inclusion of data aggregation into industrial standards such as WirelessHART are suggested, and remaining open issues for future work are presented and discussed.

  • 77.
    Dobslaw, Felix
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science.
    Tingting, Zhang
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Latency Improvement Strategies for Reliability-Aware Scheduling in Industrial Wireless Sensor Networks2015In: International Journal of Distributed Sensor Networks, ISSN 1550-1329, E-ISSN 1550-1477, article id 178368Article in journal (Refereed)
    Abstract [en]

    In this paper, we propose novel strategiesfor end-to-end reliability-aware scheduling in Industrial WirelessSensor Networks (IWSN). Because of stringent reliability requirements inindustrial applications where missed packets may have disastrous or lethalconsequences, all IWSN communication standards are based on TimeDivision Multiple Access (TDMA), allowing for deterministic channel access onthe MAC layer. We therefore extend an existing generic and scalablereliability-aware scheduling approach by name SchedEx. SchedEx has proven toquickly produce TDMA schedules that guarantee auser-defined end-to-end reliability level $\underline\rho$ for all multi-hopcommunication in a WSN. Moreover, SchedEx executes orders of magnitude fasterthan recent algorithms in the literature while producing schedules withcompetitive latencies.We generalize the original problem formulation from single-channel tomulti-channel scheduling and propose a scalable integration into the existingSchedEx approach.We further introduce a novel optimal bound that produces TDMAschedules with latencies around 20\% shorter than the original SchedExalgorithm. Combining the novel strategies with multiple sinks, multiplechannels, and the introduced optimal bound, we could through simulationsverify latency improvements by almost an order of magnitude, reducingthe TDMA super-frame execution times from tens of seconds to seconds only, whichallows for a utilization of SchedEx for many time-critical control applications.

  • 78.
    Dobslaw, Felix
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science.
    Zhang, Tingting
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    A Reliability-Aware Cross-layer Optimization Framework for Wireless Sensor Networks.Manuscript (preprint) (Other academic)
    Abstract [en]

    One of the biggest obstacles for a broad deploymentof Wireless Sensor Networks for industrial applications is the dif-ficulty to ensure end-to-end reliability guarantees while providingas tight latency guarantees as possible. In response, we proposea novel centralized optimization framework for Wireless SensorNetworks that identifies TDMA schedules and routing combi-nations in an integrated manner. The framework is shown toguarantee end-to-end reliability for all events send in a schedulingframe while minimizing the delay of all packet transmissions. Itcan further be applied using alternative Quality of Service ob-jectives and constraints including energy efficiency and fairness.We consider network settings with multiple channels, multiplesinks, and stringent reliability constraints for data collectingflows. We compare the results to those achieved by the onlyscalable reliability-aware TDMA scheduling algorithm to ourknowledge, SchedEx, which conducts scheduling only. By makingrouting part of the problem and by introducing the conceptof source-aware routing, we achieve latency improvements forall topologies, with a notable average improvement of up to31percent.

  • 79.
    Dobslaw, Felix
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science.
    Zhang, Tingting
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    End-to-End Reliability-aware Scheduling for Wireless Sensor Networks2016In: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050, Vol. 12, no 2, p. 758-767Article in journal (Refereed)
    Abstract [en]

    Wireless Sensor Networks (WSN) are gaining popularity as a flexible and economical alternative to field-bus installations for monitoring and control applications. For missioncritical applications, communication networks must provide endto- end reliability guarantees, posing substantial challenges for WSN. Reliability can be improved by redundancy, and is often addressed on the MAC layer by re-submission of lost packets, usually applying slotted scheduling. Recently, researchers have proposed a strategy to optimally improve the reliability of a given schedule by repeating the most rewarding slots in a schedule incrementally until a deadline. This Incrementer can be used with most scheduling algorithms but has scalability issues which narrows its usability to offline calculations of schedules, for networks that are rather static. In this paper, we introduce SchedEx, a generic heuristic scheduling algorithm extension which guarantees a user-defined end-to-end reliability. SchedEx produces competitive schedules to the existing approach, and it does that consistently more than an order of magnitude faster. The harsher the end-to-end reliability demand of the network, the better SchedEx performs compared to the Incrementer. We further show that SchedEx has a more evenly distributed improvement impact on the scheduling algorithms, whereas the Incrementer favors schedules created by certain scheduling algorithms.

  • 80.
    Dobslaw, Felix
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science.
    Zhang, Tingting
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    QoS Assessment for Mission-critical Wireless Sensor Network Applications2013In: Proceedings - Conference on Local Computer Networks, LCN / [ed] Matthias Wählisch, IEEE Xplore , 2013, p. 663-666Conference paper (Refereed)
    Abstract [en]

    Wireless sensor networks (WSN) must ensure worst-case end-to-end delay and reliability guarantees for mission-critical applications.TDMA-based scheduling offers delay guarantees, thus it is used in industrial monitoring and automation. We propose to evolve pairs of TDMA schedule and routing-tree in a cross-layer in order to fulfill multiple conflicting QoS requirements,exemplified by latency and reliability.The genetic algorithm we utilize can be used as an analytical tool for both the feasibility and expected QoS in production. Near-optimal cross-layer solutions are found within seconds and can be directly enforced into the network.

  • 81.
    Dobslaw, Felix
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science.
    Zhang, Tingting
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    QoS-Aware Cross-layer Configuration for Industrial Wireless Sensor Networks2016In: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050, Vol. 12, no 5, p. 1679-1691, article id 7485858Article in journal (Refereed)
    Abstract [en]

    In many applications of Industrial Sensor Networks, stringentreliability and maximum delay constraints paired with priority demands ona sensor-basis are present. These QoS requirements pose tough challenges forIndustrial Wireless Sensor Networks that are deployed to an ever largerextent due to their flexibility and extendibility.In this paper, we introduce an integrated cross-layer framework, SchedEx-GA, spanning MAC layer and networklayer. SchedEx-GA attempts to identify a network configuration that fulfills all application-specific process requirements over a topology including the sensorpublish rates, maximum acceptable delay, service differentiation, and eventtransport reliabilities. The network configuration comprisesthe decision for routing, as well as scheduling.

    For many of the evaluatedtopologies it is not possible to find a valid configuration due to the physicalconditions of the environment. We therefore introduce a converging algorithm on top of the frameworkwhich configures a given topology by additional sink positioning in order tobuild a backbone with the gateway that guaranteesthe application specific constraints.The results show that, in order to guarantee a high end-to-end reliability of 99.999% for all flows in a network containing emergency, control loop, andmonitoring traffic, a backbone with multiple sinks is often required for thetested topologies. Additional features, such as multi-channel utilization andaggregation, though, can substantially reduce the demand for required sinks.In its present version, the framework is used for centralized control, butwith the potential to be extended for de-centralized control in future work.

  • 82.
    Duan, J
    et al.
    Beijing Jiatong University.
    Yang, D
    Beijing Jiatong University.
    Zhang, S
    Beijing Jiatong University.
    Zhao, J
    Beijing Jiatong University.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    A Trust Management Scheme for Industrial Wireless Sensor Networks2013Conference paper (Refereed)
  • 83.
    Edvinsson, Joakim
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    AR-park för Android: Augmented Reality park i Sundsvall2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Målet med detta projekt är att ta fram en applikationsprototyp för Androidenheter som ska locka användare av applikationen till och tillbaka till broparken i Skönsberg med hjälp av augmented-reality. Applikationen ska känna av om användaren befinner sig inom eller utanför parkens område och visa olika bilder/modeller på specifika GPS-koordinater i det digitala lagret beroende på användarens positionering. Arbetet har genomförts i samarbete med Dohi på uppdrag av Sundsvalls kommun där regelbundna möten hafts med uppdragsgivaren. Utvecklingen av applikationen sker i PhoneGap med Wikitude-plugin. Projektet har resulterat i en applikationsprototyp som använder ActionRanges, som är en typ av GeoFence, för att presentera olika bilder hämtade från en egen server i det digitala lagret beroende på användarens position. Användarna har inom parkens område möjlighet att själv påverka de bilder som visas i det digitala lagret genom att i applikationen ta en bild som laddas upp till servern där bilderna lagras och där bilden som tagits även visar det digitala lagret.

  • 84.
    Efosa, Alohan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Building a Student Information System2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this project, I intend to design a Student Information System (SIS) that will be user-friendly and more diverse for prospective users of this platform. This application will be similar to most existing platforms such as OSIS-BSU (Online Student Information System of Benguet State University), which has a lot of interesting features for both students and teachers. In this SIS the organization or school can efficiently create, store, retrieve, delete or update student academic and information records. My main goal is to generate and improve new knowledge and promote the usage of e-learning in higher institutions. The method used to achieve this set will be done through prototyping based on paper, a survey and a literature/scientific study. The theoretical aspect consists of scripting programming languages that are processes on a server and embedded into HTML. The result was achieved through accurate evaluation of collected data through a conducted survey.  The survey confirms that the new improved SIS will not only bring dynamic changes, but also create room for e-learning environment in higher institutions in Nigeria.

  • 85.
    Eggestig, Lars
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Wodajo, Mintesinot
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Integration of BankID Services in a PhoneGap Based Mobile Application2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Security concerns became high with the rapid technology advancement andwith the open nature of the internet. BankID is the leading electronic identificationsystem in Sweden which is used by around 5 million people in a variety ofpublic and private services. BankID allows users to securely authenticate themselvesand digitally sign important documents and transactions over the internet.In 2011, BankID Security App was launched to be used in mobile smartphones and tablet computers. In this paper, different components of the PublicKey Infrastructure (PKI) which is a cryptographic technique that enables usersto safely communicate over the insecure internet has been studied in detail. Furthermore,a test BankID-integrated PhoneGap based app on the Android platformis implemented and a performance evaluation and security analysis wereperformed. The test implementation of the BankID-integrated app on theAndroid platform provides user authentication and digital signing functions.The implemented backend system consists of a server with digital certificateand a database. The performance test emphasizes on the measurement of the accesstime between the components of the system and usability of the application.Access time measurement includes a reasonable amount of time in whichthe user is able to perform different activities in the system. In usability assessmentnumber of actions to perform a certain task and the ease of the user interfacehas been taken into consideration. The security analysis aims to identifypotential security flaws in the system and discuss possible solutions. The potentialsecurity risks we identified during the implementation of the system are theman-in-the-middle-attack, the Heartbleed bug, losing the mobile device andphysical access to the backend system. The potential security risks in the systemwere examined with regard to severity and probability of occurrence. Finally,the thesis project has been discussed in terms of the future work and system expansions.The result of the thesis will be used as a base in production developmentby Dewire, the company for which the thesis work has been conducted.

  • 86.
    Ekenberg, Love
    et al.
    Dept. of Computer and Systems Sciences, Stockholm University.
    Danielson, Mats
    Dept. of Computer and Systems Sciences, Stockholm University.
    Larsson, Aron
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Sundgren, David
    Dept. of Computer and Systems Sciences, Stockholm University.
    Second-Order Risk Constraints in Decision Analysis2014In: Axioms, ISSN 2075-1680, Vol. 3, no 1, p. 31-45Article in journal (Refereed)
    Abstract [en]

    Recently, representations and methods aimed at analysing decision problems where probabilities and values (utilities) are associated with distributions over them (second-order representations) have been suggested. In this paper we present an approach to how imprecise information can be modelled by means of second-order distributions and how a risk evaluation process can be elaborated by integrating procedures for numerically imprecise probabilities and utilities. We discuss some shortcomings of the use of the principle of maximising the expected utility and of utility theory in general, and offer remedies by the introduction of supplementary decision rules based on a concept of risk constraints taking advantage of second-order distributions.

  • 87.
    Ekener, Elisabeth
    et al.
    KTH Royal Institute of Technology.
    Larsson, Aron
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems. Department of Computer and Systems Sciences, Stockholm University.
    Finnveden, Göran
    KTH Royal Institute of Technology.
    Sandin, Per
    Swedish University of Agricultural Sciences, Uppsala.
    Operationalising and incorporating ethical considerations into a tool for multi-criteria decision making2016In: International Journal of Multicriteria Decision Making, ISSN 2040-106X, E-ISSN 2040-1078, Vol. 6, no 4, p. 290-315Article in journal (Refereed)
    Abstract [en]

    In this study, an existing method for ethical analysis was extended by adding aspects of human rights and global distributional issues as framed by the United Nations (UN) Universal Declaration of Human Rights (UDHR) and the UN Millennium Development Goals (MDGs). A procedure for incorporating these issues together with environmental, safety and cost considerations into a decision making framework using multi-criteria decision analysis (MCDA) was devised. This includes a scoring system to convert qualitative ethical issues into semi-quantitative issues. The refined framework tool was tested in an illustrative case on the destruction of ammunition. The results showed that the extended framework for ethical analysis added value, for example as a way of highlighting ethical considerations in decision making. Use of the DecideIT software with its integrated MCDA improved the analysis by allowing for uncertain and imprecise values and estimations. The illustrative case results indicated that a combined alternative including recycling of metals and energetic materials had clear advantages over open detonation.

  • 88.
    Ekman, Björn
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Lageroptimering av distributionslager: optimering av framtida centrallager hos Alltank AB2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 89.
    Ekman, Niklas
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Hur gör man egentligen?: Konstruktion av en spelmotor2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In today's society individuals play computer games and many haveprobably thought, "How is it done?". To create computer games oneneeds knowledge in programming, game theory, physics and mathe­matics. A game foundation is called the game engine. A game engine isa toolkit with components such as map editor and graphics engine.There is no good overall guide for beginners on how a game engine iscreated. Windows has been dominant over OS X and Ubuntu in thegame industry. A graphics library creates a higher abstraction level torender graphics. An application framework provides commonly usedfunctionality when creating a desktop applications. A hit box is a sur­face that is used to detect when objects have collided and are separatefrom, but reflects, the 3D model. Before construction began an investiga­tion was carried about to identify problems that could arise and librariesthat could be used. Several alternatives were found and evaluated byimplementing and visually testing them. Scrum was used as the projectmethod. A function was finished when the code could compile locally, avisual tests had been performed and when a build server could compilethe code. Git was used as the version control system. To document thework a diary was used. Graphics library that was research was OGRE,Irrlicht and Horde3D. Application framework options were FLTK,SFML and Qt. Two alternative solutions were found to create hit boxes.One that recreates the 3D model triangles (triangle method) and one thatiterates through the skeleton of the 3D model and small hit boxes foreach part, and then put them all together (iteration method). All graph­ics library and application framework passed the evaluations. Iterationmethod for hit boxes was shortened from the project due to time con­straints. The graphics Library OGRE, the application framework Qt andthe triangle method was chosen for the integration of the game engine.The result was achieved but there is room for further development.

  • 90.
    Ekroth, Sebastian
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Ahlander, Gustaf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Mobil individanpassad realtidsinformation i kollektivtrafiken: En fallstudie på Tågkompaniet2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The total traveling with different types of transportation has increased drastically since the 50´s. Despite this increase, the use of the public transportation has decreased in percentage which has its explanation in the overall increased use of cars as transportation. Many researchers believes that better traffic information in the public transport can lead to increased use. Therefore this study aims to investigate how mobile personalized real-time information can increase customer satisfaction in the public transport in order to maintain and attract more travelers. The study addresses the problem through a case study at the Swedish transit agency Tågkompaniet, where customers and staff are studied in order to map the present situation regarding information in the public transport. The case study also sets out to investigate which type of real-time information that is considered to be most important for the travelers. At last the study also investigate which types of technical solutions that is needed, and how the needs of travelers can be considered to be able to offer mobile personalized real-time information. The findings are that there is a dissatisfaction regarding the transit information among both travelers and staff, and that their needs and demands must be met to a greater extent in order to increase the customer satisfaction. Furthermore, the findings are also that information attributes regarding delays and disruptions in the public transport is considered to be most important by travelers. Functions such as subscribe to information, push notifications and information associated with the transit ticket are necessary to be able to provide travelers with mobile personalized real-time information. Lastly the study provides a tool to consider traveler needs in development and evaluation of mobile personalized information systems within the public transport.

  • 91.
    Engkvist, Tobias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Remote Netlab2016Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    The projects main focus have been to create a system mainly for the users that study network technology on a more advanced level. In order for the students to start to configure the switches and routers they need to access a server with the SSH protocol which was one of the requirements. Another requirement was that only one user should be able to configure at same time (so two users should NOT be able to configure the switches and routers at the same time). The scripting languages that was used was

    bash, shell, perl and expect in order to achieve these goals and requirement. The result shows a finished product and that this project was feasable. The solution is presented as a flowchart as an overview and some regular text that explains the scripts in more depth. There are of course a ton of other ways to solve this problem and a few of them are presented and discussed in the later chapters.

  • 92.
    Eriksson, Adam
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Sharing information between services while avoiding mandatory dependencies: A survey and performance study of possible implementation options2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 93.
    Eriksson, Alexandra
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Leo, Tobias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Data visualization: Handling and visualizing large data sets2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 94.
    Eriksson, Magnus
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Rahman, S. M. Hasibur
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Fraile, Francisco
    Universitat Politècnica de València, Spain .
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Efficient Interactive Multicast over DVB-T2: Utilizing Dynamic SFNs and PARPS2013In: IEEE International Symposium on Broadband Multimedia Systems and Broadcasting, BMSB, IEEE conference proceedings, 2013, p. Art. no. 6621700-Conference paper (Refereed)
    Abstract [en]

    In the terrestrial digital TV systems DVB-T/H/T2, broadcasting is employed, meaning that all TV programs are sent over all transmitters, also where there are no viewers. This is inefficient utilization of spectrum and transmitter equipment. Applying interactive multicasting over DVB-T2 is a novel approach that would substantially reduce the spectrum required to deliver a certain amount of TV programs. Further gain would be achieved by Dynamic single-frequency network (DSFN) formations, which can be implemented using the concept of PARPS (Packet and Resource Plan Scheduling). A Zipf-law heterogeneous program selection model is suggested. For a system of four coordinated transmitters, and certain assumptions, IP multicasting over non-continuous transmission DSFN gives 1740% increase in multiuser system spectral efficiency (MSSE) in (users∙bit/s)/Hz/site as compared to broadcasting over SFN.

  • 95.
    Estlind, Björn
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Order Engine: Prestandajämförelse mellan paradigmen MTEDA och COOA2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this project has been about comparing what performance-differences there is between the paradigms MTEDA and COOA when applied for an “Order Engine”-system, a system that receives orders (tasks) from internal and external units and executes them asynchronously. The company Dewire that has developed the COOA-system has supervised the author to find out if an OE-system can benefit from using the MTEDA-paradigm. The solution for the MTEDA-system included a structure where a master-process delegate incoming orders for slave-processes, the slave-processes then executes the orders through an event-driven manner. The COOA-system on the other hand uses a thread-pool, where the orders get assigned to the threads in the pool if they are available. It turned out that the MTEDA- system executed the orders faster than the COOA-system, even though the MTEDA-system can gain- or loose execution-speed depending on the conditions of the orders. The way MTEDA delegates the orders, that is spawning and destroying processes, turned out to be more expensive for the CPU. Assigning orders to threads that are already active turned out to be an efficient way of using the resources. Both of these paradigms could be the better choice when developing an OE-system. Therefore, the things that should decide that choice is the resources available and the general conditions that the incoming orders have.

  • 96.
    Fadaeian, Vahid
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Developing and evaluating recommender systems2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In recent years, web has experienced a tremendous growth concerning users and content. As a result information overload problem has always been always one of the main discussion topics. The aim has always been to find the most desired solution in order to help users when they find it increasingly difficult to locate the accurate information at the right time. Recommender systems developed to address this need by helping users to find relevant information among huge amounts of data and they have now become a ubiquitous attribute to many websites. A recommender system guides users in their decisions by predicting their preferences while they are searching, shopping or generally surfing, based on their preferences collected from past as well as the preferences of other users. Until now, recommender systems has been vastly used in almost all professional e-commerce websites, selling or offering different variety of items from movies and music to clothes and foods. This thesis will present and explore different recommender system algorithms such as User-User Collaborative and Item-Item Collaborative filtering using open source library Apache mahout. Algorithms will be developed in order to evaluate the performance of these collaborative filtering algorithms. They will be compared and their performance will be measured in detail by using evaluation metrics such as RMSE and MAE and similarity algorithms such as Pearson and Loglikelihood.

  • 97.
    Falck, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Säkerhet: IT säkerhet på en myndighet2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 98.
    Fanchen, Li
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    A Secure Bluetooth Transfer Application in Android2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 99.
    Fard, Ali Ataei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Room Function Program and Technical Description: Interaction with BIM Models2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The move from two dimensional drawings (2D) to three dimensional (3D) models is underway in the architectural, engineering and construction industry. The three dimensional models may also be full of information which more exactly defines the different elements of a building, such models are called Building Information Modelling (BIM). Normally within a construction project, Computer-Aided Design (CAD) tools, experts add information to models and the feedback from the rest of the stakeholders are done during common meetings. The important part of information management of construction projects is the briefing process, collecting and defining the client's requirements throughout the construction project. The thesis project aims at defining and developing such tools which communicates with BIM models. Specifically, the main focus of this thesis is on creating interactive tools for Room Function Program (RFP) and Technical Description. An RFP describes the content and functionality of one or several rooms of a building that is designed at the early stage of a building construction. A Technical Description defines and describes all specifications of products which should be in a building. Current available and commonly used processes and products for RFP will be examined within this thesis as the industry has room for improvements with these particular concepts. The thesis project is conducted through research, case studies and interviews, respectively. First, the research and case studies analyzed the use and benefits of BIM. Then, the interview examined the gap between BIM, RFP and Technical Description and it is included in Appendix A. Subsequently, the RFP and Technical Description tools will be integrated with the BIM viewer successfully and desired visual feedback is given by filtering and highlighting the object in the model.

  • 100.
    Fasth, Tobias
    et al.
    Dept. of Computer and Systems Sciences, Stockholm University, Sweden.
    Larsson, Aron
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Sensitivity Analysis in Portfolio Interval Decision Analysis2013In: FLAIRS 2013 - Proceedings of the 26th International Florida Artificial Intelligence Research Society Conference, 2013, p. 609-614Conference paper (Refereed)
    Abstract [en]

    Techniques enabling decision makers to identify a set ofnon-mutually exclusive projects (or alternatives) constituting a portfolio, while allowing for imprecise information with respect to projects’ benefits, costs, andoverall resource constraints, have emerged as an areaof great applicability. To reach applicability, reasonable and computationally meaningful decision evaluation methods are needed. In this paper, we propose anembedded form of sensitivity analysis for portfolio interval decision analysis building upon the concept of interval contraction. Both a priori sensitivity analysis anda posteriori sensitivity analysis for portfolio interval decision analysis are supported by the approach.

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