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  • 1.
    Ahlqvist, Theresé
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    "Är det alltid negativt att vara konservativ?": En problematisering av stämplingen av byggbranschen som konservativ2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    When investigating the construction industry's lack of digitization, it is often explained that it is because of a conservative culture. The purpose of this study has been to problematize the labelling as conservative and to study a company in the industry to gain a deeper understanding of what other problems that may exist. Based on this, three research questions were identified which the study had as a goal to answer. These are: how the construction industry can be said to be conservative, how the conservatism is expressed, and what other barriers that exists that cannot be said to be derived from conservatism. The study has been conducted through a case study at Skanska Sverige AB with Region Hus Norr as a delimitation. Furthermore, it has been divided into two phases where semi-structural interviews and a document review have been used as the basis for a description of the current situation. The result shows that it is not a representative state of the construction industry to say that it is conservative, and during the case study no underlying expressions of conservatism was observed. On the other hand, there are several other areas that are considered as the reason for a slow development. The conclusions drawn is that the way the Swedish Public Procurement Act is conducted today is one of the reasons for this. An accelerated change process where some steps in the change management models are skipped is also seen as a reason. Furthermore, there are signs of that the current processes not always support efficient digitization, which indicates that the work in some cases only move from an analog to a digital state. Lastly, an indication of a stove pipe structure in the development area has been observed during the study, which can affect the efficiency and target improvement in a negative way.

  • 2.
    Ahlqvist, Theresé
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    "Är det alltid negativt att vara konservativ?": En problematisering av stämplingen av byggbranschen som konservativ2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    When investigating the construction industry's lack of digitization, it is often explained that it is because of a conservative culture. The purpose of this study has been to problematize the labelling as conservative and to study a company in the industry to gain a deeper understanding of what other problems that may exist. Based on this, three research questions were identified which the study had as a goal to answer. These are: how the construction industry can be said to be conservative, how the conservatism is expressed, and what other barriers that exists that cannot be said to be derived from conservatism. The study has been conducted through a case study at Skanska Sverige AB with Region Hus Norr as a delimitation. Furthermore, it has been divided into two phases where semi-structural interviews and a document review have been used as the basis for a description of the current situation. The result shows that it is not a representative state of the construction industry to say that it is conservative, and during the case study no underlying expressions of conservatism was observed. On the other hand, there are several other areas that are considered as the reason for a slow development. The conclusions drawn is that the way the Swedish Public Procurement Act is conducted today is one of the reasons for this. An accelerated change process where some steps in the change management models are skipped is also seen as a reason. Furthermore, there are signs of that the current processes not always support efficient digitization, which indicates that the work in some cases only move from an analog to a digital state. Lastly, an indication of a stove pipe structure in the development area has been observed during the study, which can affect the efficiency and target improvement in a negative way.

  • 3.
    Ahmad, Waqas
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Olsson, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Interpreting Plenoptic Images as Multi-View Sequences for Improved Compression2017Data set
    Abstract [en]

    The paper is written in the response to ICIP 2017, Grand challenge on plenoptic image compression. The input image format and compression rates set out by the competition are followed to estimate the results.

  • 4.
    Ahmad, Waqas
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Olsson, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Interpreting Plenoptic Images as Multi-View Sequences for Improved Compression2017In: ICIP 2017, IEEE, 2017, p. 4557-4561Conference paper (Refereed)
    Abstract [en]

    Over the last decade, advancements in optical devices have made it possible for new novel image acquisition technologies to appear. Angular information for each spatial point is acquired in addition to the spatial information of the scene that enables 3D scene reconstruction and various post-processing effects. Current generation of plenoptic cameras spatially multiplex the angular information, which implies an increase in image resolution to retain the level of spatial information gathered by conventional cameras. In this work, the resulting plenoptic image is interpreted as a multi-view sequence that is efficiently compressed using the multi-view extension of high efficiency video coding (MV-HEVC). A novel two dimensional weighted prediction and rate allocation scheme is proposed to adopt the HEVC compression structure to the plenoptic image properties. The proposed coding approach is a response to ICIP 2017 Grand Challenge: Light field Image Coding. The proposed scheme outperforms all ICME contestants, and improves on the JPEG-anchor of ICME with an average PSNR gain of 7.5 dB and the HEVC-anchor of ICIP 2017 Grand Challenge with an average PSNR gain of 2.4 dB.

  • 5.
    Ahmad, Waqas
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Palmieri, Luca
    Christian-Albrechts-Universität, Kiel, Germany.
    Koch, Reinhard
    Christian-Albrechts-Universität, Kiel, Germany.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Matching Light Field Datasets From Plenoptic Cameras 1.0 And 2.02018In: Proceedings of the 2018 3DTV Conference, 2018Conference paper (Refereed)
    Abstract [en]

    The capturing of angular and spatial information of the scene using single camera is made possible by new emerging technology referred to as plenoptic camera. Both angular and spatial information, enable various post-processing applications, e.g. refocusing, synthetic aperture, super-resolution, and 3D scene reconstruction. In the past, multiple traditional cameras were used to capture the angular and spatial information of the scene. However, recently with the advancement in optical technology, plenoptic cameras have been introduced to capture the scene information. In a plenoptic camera, a lenslet array is placed between the main lens and the image sensor that allows multiplexing of the spatial and angular information onto a single image, also referred to as plenoptic image. The placement of the lenslet array relative to the main lens and the image sensor, results in two different optical design sof a plenoptic camera, also referred to as plenoptic 1.0 and plenoptic 2.0. In this work, we present a novel dataset captured with plenoptic 1.0 (Lytro Illum) and plenoptic 2.0(Raytrix R29) cameras for the same scenes under the same conditions. The dataset provides the benchmark contents for various research and development activities for plenoptic images.

  • 6.
    Ahmad, Waqas
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Palmieri, Luca
    University of Padova, Italy.
    Koch, Reinhard
    Christian-Albrechts-University of Kiel, Germany.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    The Plenoptic Dataset2018Data set
    Abstract [en]

    The dataset is captured using two different plenoptic cameras, namely Illum from Lytro (based on plenoptic 1.0 model) and R29 from Raytrix (based on plenoptic 2.0 model). The scenes selected for the dataset were captured under controlled conditions. The cameras were mounted onto a multi-camera rig that was mechanically controlled to move the cameras with millimeter precision. In this way, both cameras captured the scene from the same viewpoint.

  • 7.
    Ahmad, Waqas
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Olsson, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Compression scheme for sparsely sampled light field data based on pseudo multi-view sequences2018In: SPIE Photonics Europe 2018: Proceeding, 2018Conference paper (Refereed)
    Abstract [en]

    With the advent of light field acquisition technologies, the captured information of the scene is enriched by having both angular and spatial information. The captured information provides additional capabilities in the post processing stage, e.g. refocusing, 3D scene reconstruction, synthetic aperture etc. Light field capturing devices are classified in two categories. In the first category, a single plenoptic camera is used to capture a densely sampled light field, and in second category, multiple traditional cameras are used to capture a sparsely sampled light field. In both cases, the size of captured data increases with the additional angular information. The recent call for proposal related to compression of light field data by JPEG, also called “JPEG Pleno”, reflects the need of a new and efficient light field compression solution. In this paper, we propose a compression solution for sparsely sampled light field data. In a multi-camera system, each view depicts the scene from a single perspective. We propose to interpret each single view as a frame of pseudo video sequence. In this way, complete MxN views of multi-camera system are treated as M pseudo video sequences, where each pseudo video sequence contains N frames. The central pseudo video sequence is taken as base View and first frame in all the pseudo video sequences is taken as base Picture Order Count (POC). The frame contained in base view and base POC is labeled as base frame. The remaining frames are divided into three predictor levels. Frames placed in each successive level can take prediction from previously encoded frames. However, the frames assigned with last prediction level are not used for prediction of other frames. Moreover, the rate-allocation for each frame is performed by taking into account its predictor level, its frame distance and view wise decoding distance relative to the base frame. The multi-view extension of high efficiency video coding (MV-HEVC) is used to compress the pseudo multi-view sequences. The MV-HEVC compression standard enables the frames to take prediction in both direction (horizontal and vertical d), and MV-HEVC parameters are used to implement the proposed 2D prediction and rate allocation scheme. A subset of four light field images from Stanford dataset are compressed, using the proposed compression scheme on four bitrates in order to cover the low to high bit-rates scenarios. The comparison is made with state-of-art reference encoder HEVC and its real-time implementation X265. The 17x17 grid is converted into a single pseudo sequence of 289 frames by following the order explained in JPEG Pleno call for proposal and given as input to the both reference schemes. The rate distortion analysis shows that the proposed compression scheme outperforms both reference schemes in all tested bitrate scenarios for all test images. The average BD-PSNR gain is 1.36 dB over HEVC and 2.15 dB over X265.

  • 8.
    Ahmad, Waqas
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Vagharshakyan, Suren
    Tampere University of Technology, Finland.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Gotchev, Atanas
    Tampere University of Technology, Finland.
    Bregovic, Robert
    Tampere University of Technology, Finland.
    Olsson, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Shearlet Transform Based Prediction Scheme for Light Field Compression2018Conference paper (Refereed)
    Abstract [en]

    Light field acquisition technologies capture angular and spatial information ofthe scene. The spatial and angular information enables various post processingapplications, e.g. 3D scene reconstruction, refocusing, synthetic aperture etc at theexpense of an increased data size. In this paper, we present a novel prediction tool forcompression of light field data acquired with multiple camera system. The captured lightfield (LF) can be described using two plane parametrization as, L(u, v, s, t), where (u, v)represents each view image plane coordinates and (s, t) represents the coordinates of thecapturing plane. In the proposed scheme, the captured LF is uniformly decimated by afactor d in both directions (in s and t coordinates), resulting in a sparse set of views alsoreferred to as key views. The key views are converted into a pseudo video sequence andcompressed using high efficiency video coding (HEVC). The shearlet transform basedreconstruction approach, presented in [1], is used at the decoder side to predict thedecimated views with the help of the key views.Four LF images (Truck, Bunny from Stanford dataset, Set2 and Set9 from High DensityCamera Array dataset) are used in the experiments. Input LF views are converted into apseudo video sequence and compressed with HEVC to serve as anchor. Rate distortionanalysis shows the average PSNR gain of 0.98 dB over the anchor scheme. Moreover, inlow bit-rates, the compression efficiency of the proposed scheme is higher compared tothe anchor and on the other hand the performance of the anchor is better in high bit-rates.Different compression response of the proposed and anchor scheme is a consequence oftheir utilization of input information. In the high bit-rate scenario, high quality residualinformation enables the anchor to achieve efficient compression. On the contrary, theshearlet transform relies on key views to predict the decimated views withoutincorporating residual information. Hence, it has inherit reconstruction error. In the lowbit-rate scenario, the bit budget of the proposed compression scheme allows the encoderto achieve high quality for the key views. The HEVC anchor scheme distributes the samebit budget among all the input LF views that results in degradation of the overall visualquality. The sensitivity of human vision system toward compression artifacts in low-bitratecases favours the proposed compression scheme over the anchor scheme.

  • 9.
    Ahonen, Mikko
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Designing to archive open data – Case: ISERV e-services project.2017Conference paper (Refereed)
  • 10.
    Alawi, Hussein
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Guyo, Hassan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    En värdeflödesanalys av ett reservdelslager i en fluktuerande marknad.: En fallstudie med avseende att implementera Lean.2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Företag inom stålindustrin tacklas nuförtiden med en fluktuerande och oförutsägbar marknad. Detta resulterar i försiktiga åtgärder och svårigheter med att planera och uppnå långsiktiga mål. Ovissheten leder till att beslut ibland baseras på felaktiga prognoser. I höjden av denna fluktuerande marknad behövs vanligtvis förstärkning i och med att efterfrågan ökar. Detta leder till att företag ställs inför svåra beslut, att anställa ytterligare personal och/eller utöka lagerhållning. Denna marknad kan så småningom vända och detta leder till varsel av personal samt kontraktion av depåer för att hålla en viss vinstnivå, som det tidigare har hänt. Ett av alternativen som återstår i dagsläget är effektivisering av orderhanteringsprocessen för att reducera ledtider och klara av ökande efterfrågan. Lean är en välkänd metod för att effektivera flöden i processer. Företagets reservdelslager arbetar inte med Lean i dagsläget. Syftet med denna fallstudie är att undersöka med värdeflödesanalys(VSM) och diskret händelse simulation vilka kritiska punkter och flaskhalsar som existerar i reservdelslagret och målet är att sedan eliminera de med Lean som arbetssätt. Första steget bestod av att kartlägga orderhanteringsprocessen med en processpromenad och sedan analysera de olika aktiviteterna. Detta möjliggjorde en identifiering av flaskhalsar och kritiska punkter. Resultatet presenterar ett nuläge av företaget med en cykeltid på 224 sekunder/artikel och en ledtid på 1549 sekunder/order. En order har även ett genomsnitt på 6 artiklar varav fem ligger på hyllor och en på lagerautomat. Flödet har illustrerats i ett spagettidiagram. I koppling med teorin har ett par förbättringsförslag föreslagits som exempelvis en omstrukturering av artiklar på hyllor utifrån pareto(ABC)-analys. Detta ska reducera ledtiden. Flaskhalsarna som har identifierats är osynkroniserade arbetsrutiner och ineffektiva lagerstrukturer. Därmed har ett antal effektivare framtida lägen med reducerade ledtider föreslagits. Slutsatsen är att Lean principer som ”Jidoka”(ständiga förbättringar) och Just in time(lägre ledtider i princip) kan implementeras med olika lösningar som VMI, IT och automatisering. Fortsatta studier kan utvärdera varje lösning med DES och även jämföra olika kostnader i förhållande till nytta.

  • 11.
    Albihn, Amalia
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Husveterinären: Responsiv design med WordPress2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Målet med detta projekt har varit att ta fram en responsiv webbplats åt Husveterinären

    AB. Kraven på webbplatsen var bland annat att den skulle skapas i

    WordPress, möjliggöra för kunder att ta del av uppdateringar från veterinärens

    Facebook samt innehålla ett bokningssystem. Projektet genomfördes enligt metoden

    mobile first vilket innebär att man utgår ifrån en liten skärm när man designar

    för att sedan skala upp storleken. Media queries och en flexibel layout

    baserad på relativa enheter har använts för den responsiva designen. För att utvärdera

    webbplatsens användbarhet har användartester genomförts. Resultatet

    är en webbplats som kan användas i enheter med stora såväl som med små skärmar.

    Användartesterna visade på att det var lätt att navigera mellan webbsidorna

    samt att använda både bokningssystemet och kontaktformuläret oavsett skärmstorlek.

    Med WordPress är det dessutom möjligt för veterinären att själv underhålla

    sin webbplats utan att behöva ha kunskaper om att skriva kod.

  • 12.
    Anderson, Karen
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Research in the Archival Multiverse: book review2017In: Archives and Manuscripts, ISSN 0157-6895, E-ISSN 2164-6058, Vol. 45, no 2, p. 169-170Article, book review (Other academic)
  • 13.
    Andersson, Joakim
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Affärsmodellsutveckling: Hur företag hanterar utmaningar på en förändrad marknad2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A market change comes with challenges for the organisations which operate on that market, since they must adjust to the new market conditions, a new competitive situation and such. The purpose of this study was to examine which challenges organisations experience when they develop their business models. This was performed by doing a literature review as well as interviews with representatives from the electric market in Sweden. The result from the literature review showed that multiple concepts can be connected to form an encompassing view with the change as the catalyst. Four aspects regarding challenges could be developed based on previous research: (1) he organisation is not used to change management; (2) the organisation is used to change management; (3) management does not know how to start working with BMI; and (4) management knows how to start working with BMI. The result from the interviews showed that the literature was reflected in reality, since the informants described several concepts from the literature. The informants’ organisations could be placed in the aspects which had been developed and based on previous research suggestions of how to handle these challenges could be developed, some of which the informants had already applied (but not fully, yet).

  • 14.
    Andersson, Joakim
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Bizimana, Mike
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Digitalisering och kundnytta: En undersökning om digitaliserings effekt på ett företag och dess kunder2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In today’s society, businesses and organizations are facing increasing challenges to change and adapt to a digitizing world. In order to stay relevant in the market, businesses need to work constantly on developing and improving the efficiency of its various processes. This study is designed as a case study at MittSverige Vatten & Avfall which is a municipal corporation in Sundsvall municipality. Its goal is to be a leader in its sector by the year 2021. The study’s objective was to investigate if the digitization of information gathering could bring benefit to a company and its customers. The investigation has focused on the digitization of information gathering from the customer's water meter. The study's objective has been to identify and analyze how digitization impacts business processes and its financial condition with help from value stream mapping and a customer survey. The study was conducted with the support of written and web based literary sources. A survey as well as interviews was conducted. An investment analysis has been conducted to study and evaluate the benefits that the investment brings the customer and MittSverige Vatten & Avfall regarding cost. The study proved that the digitization of water meters would mean an improvement for both MittSverige Vatten & Avfall and its customers.

  • 15.
    Andersson, Åsa
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Ismail, Abdiqafar
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Ruttoptimering: En jämförelse mellan mänsklig erfarenhet och optimeringsprogram2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Route optimization aims to optimize routes for vehicles withregards to resource usage. Especially when the vehicle needsto visit multiple customers on the route, a route optimizationtool is beneficiary. The purpose of this study is to comparehuman experience with a route optimization program. This isdone by comparing how a truck driver makes his routes to theroute a GIS-tool has calculated and then see which of theroutes was shorter, measured in kilometers. The data for thisstudy was gathered from a big shipping company. In order toachieve the purpose of this study 10 routes were analysed bya GIS program called ArcGIS. The algorithm used by ArcGISin route optimization is tabu search, this type of program wasused because it is based on heuristic methods that is muchfaster than exact methods. Expert systems are based onknowledge from experts that have been accumulated duringmany years of experience. Providing recommendations basedon probability reasoning instead of absolute answer. Thesekind of systems is often used in GIS programs to improveresults and calculation time. The aim of this study wasanalyze if a optimization program finds a better route than theexpert. This study shows an improvement of 60% of theanalyzed routes. To verify the results of this study anhypothesis test was made which gave a level of significanceby more than 85 %. The routes were optimized to a certainextent even before the study was done due to the driveralready being familiar with the routes in question. Because ofthis the results of this study were lower compared to othersimilar studies. Another reason may be that the coordinatesgiven to us did not always correspond perfectly with actuallocation of the stops.

  • 16.
    Aqeel-ur, Rehman
    et al.
    COMSATS Institute of Information Technology, Vehari, Pakistan.
    Liao, Xiaofeng
    College of Electronics and Information Engineering, Southwest University, Chongqing, China.
    Hahsmi, Muntazim Abbas
    Khawaja Fareed University of Engineering and IT, RYK, Pakistan.
    Haider, Rizwan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    An efficient mixed inter-intra pixels substitution at 2bits-level for image encryption technique using DNA and chaos2018In: Optik (Stuttgart), ISSN 0030-4026, E-ISSN 1618-1336, Vol. 153, p. 117-134Article in journal (Refereed)
    Abstract [en]

    In this paper, an image encryption system is proposed that uses only addition operation to achieve higher efficiency at diffusion phase after DNA encoding at pixel level. The image is first permuted and then encoded into DNA bases using sub-set of DNA complementary rules chaotically. Afterwards, the adjacent columns of DNA encoded image are added in the substitution phase named as inter-intra pixels substitution which followed by row addition named as inter-pixels substitution. This substitution is performed by adding DNA bases where each DNA base is composed of 2-bits. The addition operation performs randomly between DNA bases named mixed inter-intra pixel substitution. To strengthen security, initial conditions for chaotic maps are computed from SHA-256 hash of plain image which leads to enhance the resistance against known/chosen-plaintext and differential attacks. Due to fewer computational operations, the efficiency of the proposed cipher is high. The simulated results show that the proposed technique is extremely robust against statistical and differential attacks. It successfully surpassed the statistical tests such as Histogram, Correlation, Chi-Square and Entropy. For differential attack, it passed quantitative as well as qualitative Number of Pixel Change Rate (NPCR) and Unified Average Cipher Intensity (UACI) tests in a single round of encryption. 

  • 17.
    Ascorti, Leonardo
    et al.
    Pepperl+Fuchs, Sulbiate, Italy.
    Savazzi, Stefano
    Institute of Electronics, Computer and Telecommunication Engineering, Milano, Italy.
    Soatti, Gloria
    Informazione e Bioingegneria, Politecnico di Milano, Milano, Italy.
    Nicoli, Monica
    Informazione e Bioingegneria, Politecnico di Milano, Milano, Italy.
    Sisinni, Emiliano
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology. University of Brescia, Brescia, Italy.
    Galimberti, Stefano
    Pepperl+Fuchs, Sulbiate, Italy.
    A Wireless Cloud Network Platform for Industrial Process Automation: Critical Data Publishing and Distributed Sensing2017In: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 66, no 4, p. 592-603, article id 7851047Article in journal (Refereed)
    Abstract [en]

    Wireless technologies combined with advanced computing are changing industrial communications. Industrial wireless networks can improve the monitoring and the control of the entire system by jointly exploiting massively interacting communication and distributed computing paradigms. In this paper, we develop a wireless cloud platform for supporting critical data publishing and distributed sensing of the surrounding environment. The cloud system is designed as a self-contained network that interacts with devices exploiting the time synchronized channel hopping protocol (TSCH), supported by WirelessHART (IEC 62591). The cloud platform augments industry-standard networking functions as it handles the delivery (or publishing) of latency and throughput-critical data by implementing a cooperative-multihop forwarding scheme. In addition, it supports distributed sensing functions through consensus-based algorithms. Experimental activities are presented to show the feasibility of the approach in two real industrial plant sites representative of typical indoor and outdoor environments. Validation of cooperative forwarding schemes shows substantial improvements compared with standard industrial solutions. Distributed sensing functions are developed to enable the autonomous identification of recurring cochannel interference patterns.

  • 18.
    Axell, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    LAN Segmentering: Implementering av VTP version 3 och MST2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The company is on the verge of segmenting their network and the reasons for this are to get a more secure production by creating a controlled and isolated environment, protecting against the spread of virus and  other threats and aswell creating cost savings by not updating or upgrading unnecessary equipment just to meet the network policy. In order to facilitate the company's segmentation needs, this independent project has been about implementing VTP version 3 and MST. VTP sends out VLAN and MST updates around the network and ease the use of PVLAN. MST is a Spanning Tree protocol that enables VLAN to be mapped to instances to save CPU utilization on the switches as well to help load balance the network. The method used was to set up a test environment from backups from the real network where it was tested to implement the new protocols and to see how they acted. An evaluation of the network was made where selected switches and interfaces were measured before the implementation to be compared later with the same measurements after the implementation was completed. It turned out that the results before implementation were low enough that the implementation of MST was postponed until the network segmentation was completed. VTP version 3 was implemented without any problems and three different scenarios with complete configuration were created to help the company take the leap to MST in the future.

  • 19.
    Barile, Gianluca
    et al.
    University of l'Aquila, Via Gronchi, L'Aquila, Italy.
    Ferri, Giuseppe
    University of l'Aquila, Via Gronchi, L'Aquila, Italy.
    Parente, Francesca Romana
    University of l'Aquila, Via Gronchi, L'Aquila, Italy.
    Stornelli, Vincenzo
    University of l'Aquila, Via Gronchi, L'Aquila, Italy.
    Depari, Alessandro
    University of l'Aquila, Via Gronchi, L'Aquila, Italy.
    Flammini, Alessandra
    University of Brescia, Brescia, Italy.
    Sisinni, Emiliano
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology. University of Brescia, Brescia, Italy.
    A standard CMOS bridge-based analog interface for differential capacitive sensors2017In: PRIME 2017 - 13th Conference on PhD Research in Microelectronics and Electronics, Proceedings, IEEE, 2017, p. 281-284, article id 7974162Conference paper (Refereed)
    Abstract [en]

    This work describes an analog electronic interface, based on a modified De Sauty AC bridge, performing a differential capacitive sensor estimation. A suitable feedback loop tunes a Voltage Controlled Resistor to balance the bridge. The electronic circuit has been designed in a standard integrated CMOS technology (AMS 0.35μm) with a low supply voltage (±1.5 V) and a reduced power consumption (lower than 4mW). PSpice simulation results show a very good agreement with theoretical expectations. The output voltage accuracy shows a 0.03V maximum absolute error for a range of ±50% of sensor variations from its baseline value. Very small baseline values are allowed (tens of μF). 

  • 20.
    Beltramelli, Luca
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Österberg, Patrik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Modelling of EnergyConsumption in IEEE 802.11.ah Networks for M2M Traffic2016In: Proceedings of SNCNW 2016: The 12th Swedish National Computer Networking Workshop, 2016, p. 38-41Conference paper (Refereed)
    Abstract [en]

    IEEE 802.11ah is a sub-1 GHz standard designed to meet the requirements of future machine-to-machine (M2M) communications. The standard should be able to support use cases for the M2M communications with thousands of stations capable of generating both periodic and aperiodic traffic for a single access point. In some cases, like environmental and agricultural monitoring. the nodes are typically powered by battery or through energy harvesting. For this application it is important for the communication to be energy efficient. IEEE 802.11ah introduces new energy saving mechanisms and a novel channel access mechanism to achieve this objective even for networks with a large nodes number. This work proposes a mathematical model to compute the energy consumption of an IEEE 802.11ah network.

  • 21.
    Beltramelli, Luca
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Österberg, Patrik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Jennehag, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Hybrid MAC Mechanism for Energy Efficient Communication in IEEE 802.11ah2017In: Proceedings of the 2017 IEEE International Conference on Industrial Technology (ICIT), IEEE, 2017, p. 1295-1300, article id 7915550Conference paper (Refereed)
    Abstract [en]

    Many applications for machine-to-machine (M2M) communications are characterized by large numbers of devices with sporadic transmissions and subjected to low energy budgets. This work addresses the importance of energy consumption by proposing a new Medium Access Control (MAC) mechanism for improving the energy efficiency of IEEE 802.11ah, a standard targeting M2M communication. We propose to use the features of IEEE 802.11ah MAC to realize a hybrid contention-reservation mechanism for the transmission of uplink traffic. In the proposed mechanism, any device with a buffered packet will first notify the Access Point (AP) during a contention phase before being given a reserved timeslot for the data transmission. We develop a mathematical model to analyse the energy consumption ofthe proposed mechanism and of IEEE 802.11ah. The results show that for a monitoring scenario, the proposed contention reservation mechanism reduces the energy consumption for a successful uplink data transmission by up to 55%.

  • 22.
    Berg, Isabel
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    George JR, Home automation system interface2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    I have developed an interactive graphical user interface (GUI), which displays the current statuses of my personal home automation system based on relevance. Relevance is determined by event, such as motion detection, triggered by connected subsystems. The interface updates the order the

    subsystems are displayed to give the user faster access to relevant status overviews and controls. Event logs and controllers are accessible through HomeSeer via a JSON API.

    The application is built with HTML, CSS, JavaScript (jQuery) only. Its test program uses PHP features. All graphic elements are vectors for responsiveness.

    The application is launched on a local IIS server, achieved by converting the application to an ASP.NET website.

    I have carried out this project and written all code for it alone.

     

  • 23.
    Bergman, Ken
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Företagspresentation: Med WordPress och typografi2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Målet med detta projektet har varit att utveckla en webbplats åt ett företag med

    webbutveckling och användbarhet som kärnverksamhet. För att knyta designen

    och layouten till företagets verksamhet, så har projektet valt att titta på vad

    typografi för webb innebär, och hur det kan implementeras på webbplatsen.

    Resultatet ska ligga till grund för projektets webbplats samt framtida produkter

    och tjänster till företaget. Webbplatsen har utvecklats som ett tema för

    innehållshanteringssystem WordPress, tillsammans med ett eget

    insticksprogram för att utöka funktionaliteten till att innefatta en kontakt

    funktion. Det kompletta temat, typografi, layout och dess funktioner har

    utvecklats genom att använda HTML5, CSS samt PHP, tillsammans med en

    lokal webbserver och relationsdatabsen MySQL. Rapporten följer projekts

    utveckling av en webbplats som är både dynamisk och anpassar sin typografi

    och layout till storleken på användarens enhet, samt presenterar produkten av

    projektet.

  • 24.
    Bertilsson, Jonathan
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Bodin, Kristoffer
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Processutveckling: En fallstudie om VSM kombinerat med diskret händelsestyrd simulering kan effektivisera lastningsprocessen hos en logistikverksamhets hamnterminal2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    För att upprätthålla sin konkurrenskraft krävs det idag att ett fokus läggs på att ständigt förbättra sina processer inom organisationen. Detta faller sig logiskt, men att ta fram underlag för vilka förbättringsåtgärder som bör implementeras till processen kan vara svårt. Syftet med denna studie är att undersöka hur value stream mapping (VSM) tillsammans med diskret händelsestyrd simulering (DES) kan användas inom lastningsprocesser hos hamnliggande logistikverksamheter för att kartlägga processen, identifiera flaskhalsar samt att undersöka det teoretiska utfallet vid implementation av potentiella förbättringsåtgärder. Svaret på detta genererades via en fallstudie på SCA Logistics där en lastningsprocess analyserades från ett av deras lager som start till slutet av processen när produkten är lastad på ett fartyg. Först skapades en VSM samt en DES-modell av nuläget. Nulägets VSM bidrog till en översikt över den aktuella processen och till att validera DES-modellen. Därefter med Lean-principer som grundpelare och med hjälp av intervjuer kunde tre förbättringsåtgärder identifieras. Dessa förbättringsåtgärder applicerades till DES-modellen en i taget för att undersöka hur de påverkar systemet. De två framstående förbättringsåtgärderna testades även ihop. Resultatet visade på att processen blev mer effektiv, i form av kortare ledtid, och två nya VSM togs fram för att bidra med ytterligare visualiserande information. Åtgärderna har andra spärrar i praktiken som inte visas via varken DES eller VSM såsom höga kostnader eller hinder i lagerförhållanden. Undersökningen ledde till den slutsatsen att VSM kan användas som komplement till DES för att bidra med ett teoretiskt underlag för huruvida en förbättringsåtgärd bör implementeras. Som rekommendation bör även en kostnadsnyttoanalys genomföras för att undersöka huruvida nyttan uppväger för kostnaden.

  • 25.
    Borgerud, Charlotte
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Insyn eller intrång i forskningsvärlden?: Universitetsarkivens roll för att uppfylla nuvarande och kommande krav på öppen forskningsdata2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Ända sedan Internets grundande har olika rörelser bildats som förespråkat attforskning ska göras fritt tillgängligt för att komma runt de juridiska, ekonomiska ochtekniska problem som kan uppstå vid offentliggörande av forskningsresultat. Därförhar EU instiftat ett ramprogram för forskning och innovation där 80 miljarder Euroska fördelas ut över sju år (2014-2020) med ändamålet att stärka forskning ochinnovation samt säkerhetsställa dess allmännytta. EU har beslutat attforskningsresultat ska göras öppet tillgängligt även om undantag kan få förekomma.Även i Sverige har open access ökat i betydelse och fått allt mer stöd från såvälfinansiärer som universitet och regeringen. Regeringen har konstaterat attforskningsresultat i form av forskningsdata och vetenskapliga publikationerfinansierade med offentliga medel ska göras öppet tillgängligt i största möjliga mån.Frågan är dock om aktörerna och lärosätena är redo för att implementera dennaförändring. Tidigare studier har visat att insamlandet och bevarandet avforskningsdata ofta är omgivet av otydliga regler och brist på övergripande struktur.Till exempel bereds inte arkiveringsfrågan tillräckligt mycket utrymme i sambandmed forskningsprojekt och mycket okunskap verkar råda där forskare tenderar attspara sitt material på plattformar som inte är arkivbeständiga. Detta riskerar göra attviktig information går förlorad för framtida forskning. Syftet är därför att undersökatillvaratagandet och tillgängliggörandet av lärosätenas forskningsmaterial.Studien har använt sig av semistrukturerade intervjuer över telefon. Sammantagethar 15 intervjuer utförs med olika svenska lärosäten samt med aktörer som haft olikauppdrag med att utreda implementeringen av öppet tillgängliggörande avforskningsdata och vetenskapliga publikationer.Sammanfattningsvis är resultatet att bristen på samordning, resurser, enhetligabegrepp, infrastruktur och riktlinjer om vad som ska bevaras för evigt, vad som kangallras, vad som kan tillgängliggöras och hur det ska gå till kopplas till ett störreinformationsförvaltningsproblem där att man ännu inte i tillräcklig grad kommitigång med arbetet med arkivering av forskningshandlingar i pappersformat ocharkiven ligger efter med den digitala hanteringen i brist på e-arkiv och infrastruktursamt övergripande direktiv om metadatastandarder och digital långtidsarkivering.Slutsatsen är att arkiven som har en avgörande roll med att uppfylla nuvarande ochkommande krav på öppna forskningsdata inte arbetar tillräckligt aktivt, inte ens medforskningsarkiveringsbiten. Mer resurser behövs för att komma igång medforskningsarkivering och för kompetensutveckling. Samtidigt måste även arkivariernasjälva ta ett större ansvar för att hålla sig uppdaterade om vad som händer nationelltoch internationellt.

  • 26.
    Borglund, Erik A. M.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    The Role of Artefacts in Creating a Common Operational Picture During Large Crises2017In: ISCRAM 2017 Conference Proceedings: 14th International Conference on Information Systems for Crisis Response and Management / [ed] Tina Comes, Frédérick Bénaben, Chihab Hanachi, Matthieu Lauras, Aurélie Montarnal, 2017, p. 191-203Conference paper (Refereed)
  • 27.
    Borglund, Erik A. M.
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Engvall, Tove
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Authenticity in open data: contributions from archival science2016In: Pre-ICIS Workshop on E-Government, 2016Conference paper (Refereed)
  • 28.
    Borglund, Erik A. M.
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Öberg, Lena-Marie
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science.
    Using Scenario Planning and Personas as an Aid to Reducing Uncertainty About Future Users2017In: Emerging Trends in Archival Science / [ed] Karen F. Gracy, London: Rowman & Littlefield International, 2017, 1, p. 111-138Chapter in book (Refereed)
  • 29.
    Brunnström, Kjell
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology. RISE ICT/Acreo, Stockholm.
    Allison, R. S.
    York University, Centre for Vision Research, Toronto, Canada.
    Chandler, D. M.
    Dolby Laboratories, United States.
    Colett, H.
    Intel Corp., Santa Clara, CA, United States.
    Corriveau, P.
    Intel Corp., Santa Clara, CA, United States.
    Daly, S.
    Dolby Laboratories, United States.
    Goel, J.
    Qualcomm, Display Video Processing Group, Markham, Canada.
    Knopf, J.
    Intel Corp., Santa Clara, CA, United States.
    Wilcox, L. M.
    York University, Centre for Vision Research, Toronto, Canada.
    Yaacob, Y.
    Shizuoka University, Hamamatsu, Shizuoka, Japan.
    Yang, S. -N
    Pacific University, Forest Grove, OR, United States.
    Zhang, Y.
    Shizuoka University, Hamamatsu, Shizuoka, Japan.
    Industry and business perspectives on the distinctions between visually lossless and lossy video quality: Mobile and large format displays2017In: IS and T International Symposium on Electronic Imaging Science and Technology, Society for Imaging Science and Technology , 2017, Vol. F130042, p. 118-133Conference paper (Refereed)
    Abstract [en]

    This paper will explore the mobile and business perspectives of visually lossless image quality, as well as review recent scientific advances. It is the outcome from the Special Session on Visually Lossless Video Quality for Modern Devices: Research and Industry Perspectives organized at the Human Vision and Electronic Imaging 2017 by IS&T at San Francisco Airport, Burlingame, California, USA, Jan 29 - Feb 2, 2017. It summarizes four presentations and a panel discussion.

  • 30.
    Brunnström, Kjell
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology. Acreo Swedish ICT AB, Kista.
    Barkowsky, M.
    University of Nantes, Nantes, France.
    Balancing type I errors and statistical power in video quality assessment2017In: IS and T International Symposium on Electronic Imaging Science and Technology, Society for Imaging Science and Technology , 2017, Vol. F130042, p. 91-96Conference paper (Refereed)
    Abstract [en]

    This paper analyzes how an experimenter can balance errors in subjective video quality tests between the statistical power of finding an effect if it is there and not claiming that an effect is there if the effect it is not there i.e. balancing Type I and Type II errors. The risk of committing Type I errors increases with the number of comparisons that are performed in statistical tests. We will show that when controlling for this and at the same time keeping the power of the experiment at a reasonably high level, it will require more test subjects than are normally used and recommended by international standardization bodies like the ITU. Examples will also be given for the influence of Type I error on the statistical significance of comparing objective metrics by correlation.

  • 31.
    Brunnström, Kjell
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology. RISE Acreo AB.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Imran, Muhammad
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design. HIAB AB.
    Pettersson, Magnus
    HIAB AB.
    Johanson, Mathias
    Alkit Communications AB.
    Quality Of Experience For A Virtual Reality Simulator2018In: Human Vision and Electronic Imaging (HVEI), 2018Conference paper (Refereed)
    Abstract [en]

    In this study, we investigate a VR simulator of a forestrycrane used for loading logs onto a truck, mainly looking at Qualityof Experience (QoE) aspects that may be relevant for taskcompletion, but also whether there are any discomfort relatedsymptoms experienced during task execution. The QoE test hasbeen designed to capture both the general subjective experience ofusing the simulator and to study task completion rate. Moreover, aspecific focus has been to study the effects of latency on thesubjective experience, with regards both to delays in the cranecontrol interface as well as lag in the visual scene rendering in thehead mounted display (HMD). Two larger formal subjectivestudies have been performed: one with the VR-system as it is andone where we have added controlled delay to the display updateand to the joystick signals. The baseline study shows that mostpeople are more or less happy with the VR-system and that it doesnot have strong effects on any symptoms as listed in the SSQ. In thedelay study we found significant effects on Comfort Quality andImmersion Quality for higher Display delay (30 ms), but verysmall impact of joystick delay. Furthermore, the Display delay hadstrong influence on the symptoms in the SSQ, as well as causingtest subjects to decide not to continue with the completeexperiments, and this was also found to be connected to the longerDisplay delays (≥ 20 ms).

  • 32.
    Butun, Ismail
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Pereira, Nuno
    Polytechnic Institute of Porto, Porto, Portugal .
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Analysis of LoRaWAN V1.1 Security2018In: Proceedings of the 4th ACM MobiHoc Workshop on Experiences with the Design and Implementation of Smart Objects (SMARTOBJECTS '18)., ACM Digital Library, 2018Conference paper (Refereed)
    Abstract [en]

    LoRa and the LoRaWAN specification is a technology for Low Power Wide Area Networks (LPWAN) designed to allow connectivity for connected objects, such as remote sensors. Several previous works revealed various weaknesses regarding the security of LoRaWAN v1.0 (the official 1st draft) and these led to improvements included in LoRaWAN v1.1, released on Oct 11, 2017. In this work, we provide the first look into the security of LoRaWAN v1.1. We present an overview of the protocol and, importantly, present several threats to this new version of the protocol. Besides, we propose our own ramification strategies for the mentioned threats, to be used in developing next version of LoRaWAN. The threats presented were not previously discussed, they are possible even within the security assumptions of the specification and are relevant for practitioners implementing LoRa-based applications as well researchers and the future evolution of the LoRaWAN specification.

  • 33.
    Bylund, Patrick
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    JMS communication: Communicating with a legacy JMS broker using JavaScript2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The objective of this thesis is to research how to use JavaScript to communicate with a legacy JMS broker, specifically OpenMQ 4.1 and implementing a proof- of-concept of this. This proof-of-concept should be able to send and receive JMS messages. The necessary preparations for designing this application was to research possible ways of communicating with different JMS brokers using oth- er languages than Java. This research showed that the only viable method in or- der to communicate with this version of OpenMQ is to create a Java bridge be- tween JavaScript and the JMS broker. The results shows that it's possible to use JavaScript to communicate with OpenMQ 4.1 by using a Java Bridge together with NodeJS. This result is performed by making an integration test, by first sending a message with a certain ID to the API and then receiving a response at the intended response destination with the same ID. The front-end of the proof- of-concept provides a web application UI for performing this integration test. Future improvements of this implementation can be done by extending the Java Bridge and API in such a way that it can be used against many different JMS brokers. The configuration data used can also be stored in more reliable ways, if multiple users are using the API and web application at the same time, for example by using a database instead of JSON files.

  • 34.
    Bäckstedt, Dennis
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Felsökning och optimering av trådlöst nätverk IEEE 802.11ac2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Wireless networks are growing ever more and the norm is now that in an office or home you can

    settle down with your laptop and work without having to worry about network outlets or wires. IP

    telephony and tablet are now more natural in many users daily lives, and especially IP telephony

    places high demands on the network to which it is connected. Therefore, I have chosen that in this

    report, look at the 802.11 wireless technology developed by the IEEE standardization organization.

    The method I chose to use to accomplish this is to perform a measurement of an existing wire-

    less network. I will then investigate this data in order to hopefully submit a proposal for a better

    network design. As a tool for carrying out this measurement, I have equipment from Ekahau, a

    Finnish company whose main aim is measurement, optimization and troubleshooting of wireless

    networks. What I found out was that the wireless network had major shortcomings. In particular,

    coverage was a matter of concern, not just the lack of coverage, but sometimes even for good cove-

    rage, resulting in sticky clients. I have then presented a design that, in order to minimize costs and

    environmental impact, uses existing equipment, but requires that it be supplemented with 9 new

    access points.

  • 35.
    Cai, Zhipeng
    et al.
    Georgia State Univ, Atlanta, GA, USA.
    Chang, Rong N.
    IBM TJ Watson Res Ctr, Yorktown Hts, NY USA.
    Forsström, Stefan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Kos, Anton
    Univ Ljubljana, Ljubljana, Slovenia.
    Wang, Chaokun
    Tsinghua Univ, Beijing, Peoples R China.
    Privacy in the Internet of Things2018In: Wireless Communications & Mobile Computing, ISSN 1530-8669, E-ISSN 1530-8677, Vol. 2018, article id 8281379Article in journal (Other academic)
  • 36.
    Carlberg, Michael
    et al.
    Örebro Univ, Örebro.
    Koppel, Tarmo
    Tallinn Univ Technol, Tallinn, Estonia.
    Ahonen, Mikko
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Hardell, Lennart
    Örebro Univ, Örebro.
    Case-control study on occupational exposure to extremely low-frequency electromagnetic fields and glioma risk2017In: American Journal of Industrial Medicine, ISSN 0271-3586, E-ISSN 1097-0274, Vol. 60, no 5, p. 494-503Article in journal (Refereed)
    Abstract [en]

    Background

    Exposure to extremely low-frequency electromagnetic fields (ELF-EMF) was in 2002 classified as a possible human carcinogen, Group 2B, by the International Agency for Research on Cancer at WHO.

    Methods

    Life time occupations were assessed in case-control studies during 1997-2003 and 2007-2009. An ELF-EMF Job-Exposure Matrix was used for associating occupations with ELF exposure (T). Cumulative exposure (T-years), average exposure (T), and maximum exposed job (T) were calculated.

    Results

    Cumulative exposure gave for astrocytoma grade IV (glioblastoma multiforme) in the time window 1-14 years odds ratio (OR)=1.9, 95% confidence interval (CI)=1.4-2.6, p linear trend <0.001, and in the time window 15+ years OR=0.9, 95%CI=0.6-1.3, p linear trend=0.44 in the highest exposure categories 2.75+ and 6.59+ T years, respectively.

    Conclusion

    An increased risk in late stage (promotion/progression) of astrocytoma grade IV for occupational ELF-EMF exposure was found.

  • 37.
    Carlberg, Michael
    et al.
    Örebro Univ, Örebro.
    Koppel, Tarmo
    Tallinn Univ Technol, Tallinn, Estonia.
    Ahonen, Mikko
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Hardell, Lennart
    Örebro Univ, Örebro.
    Case-Control Study on Occupational Exposure to Extremely Low-Frequency Electromagnetic Fields and the Association with Meningioma2018In: BioMed Research International, ISSN 2314-6133, E-ISSN 2314-6141, article id 5912394Article in journal (Refereed)
    Abstract [en]

    Objective. Exposure to extremely low-frequency electromagnetic fields (ELF-EMF) was in 2002 classified as a possible human carcinogen, Group 2B, by the International Agency for Research on Cancer at WHO based on an increased risk for childhood leukemia. In case-control studies on brain tumors during 1997-2003 and 2007-2009 we assessed lifetime occupations in addition to exposure to different agents. The INTEROCC ELF-EMF Job-ExposureMatrix was used for associating occupations with ELF-EMF exposure (mu T) with meningioma. Cumulative exposure (mu T-years), average exposure (mu T), and maximum exposed job (mu T) were calculated. Results. No increased risk for meningioma was found in any category. For cumulative exposure in the highest exposure category 8.52+ mu T years odds ratio (OR) = 0.9, 95% confidence interval (CI) = 0.7-1.2, and.. linear trend = 0.45 were calculated. No statistically significant risks were found in different time windows. Conclusion. In conclusion occupational ELF-EMF was not associated with an increased risk for meningioma.

  • 38.
    Carlson, David
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    UTM-verktyg åt Roxtec2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Det denna rapport kommer att avhandla är ett projekt genomfört hos Roxtec AB, syftet har i

    detta projekt varit att underlätta hanteringen av så kallade utm-adresser. Vi kommer att gå

    igenom problemställning, hur vi väljer att lösa samma problem. Senare kommer vi att

    behandla hur vi löste de här problemen, huvudsyftet har varit att skapa ett enkelt verktyg för

    att generera nyss nämnda adresser. Lite extrafunktioner runt de här funktionerna kommer att

    avhandlas såsom sparning av historik, inlogg och så vidare. Projektet kom att innehålla många

    rader kod, de här kommer inte rapporten att avhandla i detalj, förutom vissa mer

    betydelsefulla delar av projektet. I de mer betydelsefulla avsnittet går vi igenom dess funktion

    samt med illustrationer försöker vi förklara dess syfte på ett enkelt sätt. Hur väl vi lyckats att

    lösa de uppställda problemen vi ställs inför går vi igenom och diskuterar även de här till sist.

    Projektet kommer att skapas i .NET och i lämplig programvara för att utföra och lösa senare

    uppställd problematik.

  • 39.
    Carlsson, Marcus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Problemen i ett utvecklingsteam: Inriktning mot versionshantering och agil utveckling2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Målet med min rapport har varit att undersöka de svårigheter och problem som

    utvecklare på Barnebys kan ställas inför under sitt dagliga arbete. För att

    begränsa mig har jag valt två stora områden att undersöka, det agila arbetssättet

    och versions hanteringssystem. Men det viktigaste fokuset i rapporten är vilka

    problem som uppstår som är relaterade att man jobbar flera utvecklare på

    samma projekt. Så kallade teams. Rapporten avhandlar en teoretisk bakgrund

    till de båda ämnena och sedan så genomför jag en undersökning bland de

    anställda på Barnebys teknikavdelning. Undersökningen görs medhjälp av

    Google Forms och här finns frågor kring dessa ämnen. Rapporten tar också upp

    förslag på lösningar och/eller förbättringar. Rapporten avslutas med en

    presentation av resultatet och egna reflektioner.

  • 40.
    Comstedt, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Effect of additional compression features on h.264 surveillance video2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In video surveillance business, a recurring topic of discussion is quality versus data usage. A higher quality allows for more details to be captured at the cost of a higher bit rate, and for cameras monitoring events 24 hours a day, limiting data usage can quickly become a factor to consider. The purpose of this thesis has been to apply additional compression features to a h.264 video steam, and evaluate their effects on the videos overall quality. Using a surveillance camera, recordings of video streams were obtained. These recordings had constant GOP and frame rates. By breaking down one of these videos to an image sequence, it was possible to encode the image sequence into video streams with variable GOP/FPS using the software Ffmpeg. Additionally a user test was performed on these video streams, following the DSCQS standard from the ITU-R recom- mendation. The participants had to subjectively determine the quality of video streams. The results from the these tests showed that the participants did not no- tice any considerable difference in quality between the normal videos and the videos with variable GOP/FPS. Based of these results, the thesis has shown that that additional compression features can be applied to h.264 surveillance streams, without having a substantial effect on the video streams overall quality.

  • 41.
    Crema, C.
    et al.
    University of Brescia, Brescia, Italy.
    Depari, A.
    University of Brescia, Brescia, Italy.
    Flammini, A.
    University of Brescia, Brescia, Italy.
    Sisinni, Emiliano
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology. University of Brescia, Brescia, Italy.
    Haslwanter, T.
    University of Applied Sciences Upper Austria, Linz, Austria.
    Salzmann, S.
    University of Applied Sciences Upper Austria, Linz, Austria.
    IMU-based solution for automatic detection and classification of exercises in the fitness scenario2017In: SAS 2017 - 2017 IEEE Sensors Applications Symposium, Proceedings, IEEE, 2017, article id 7894068Conference paper (Refereed)
    Abstract [en]

    Causal relationship between physical activity and prevention of several diseases has been known for some time. Recently, attempts to quantify dose-response relationship between physical activity and health show that automatic tracking and quantification of the exercise efforts not only help in motivating people but improve health conditions as well. However, no commercial devices are available for weight training and calisthenics. This work tries to overcome this limit, exploiting machine learning technique (particularly Linear Discriminant Analysis, LDA) for analyzing data coming from wearable inertial measurement units, (IMUs) and classifying/counting such exercises. Computational requirements are compatible with embedded implementation and reported results confirm the feasibility of the proposed approach, offering an average accuracy in the detection of exercises on the order of 85%.

  • 42.
    Crema, Claudio
    et al.
    University of Brescia, Brescia, Italy.
    Depari, Alessandro
    University of Brescia, Brescia, Italy.
    Flammini, Alessandra
    University of Brescia, Brescia, Italy.
    Sisinni, Emiliano
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology. University of Brescia, Brescia, Italy.
    Vezzoli, Angelo
    University of Brescia, Brescia, Italy.
    Bellagente, Paolo
    University of Brescia, Brescia, Italy.
    Virtual Respiratory Rate Sensors: An Example of A Smartphone-Based Integrated and Multiparametric mHealth Gateway2017In: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 66, no 9, p. 2456-2463, article id 7949106Article in journal (Refereed)
    Abstract [en]

    In the last few years, several wearables appeared in the market, for fitness and healthcare applications. Such smart devices have been proposed as a possible solution for lowering the costs of healthcare, leading to the mHealth revolution. In the typical scenario, each wearable, embedding sensors, processing units and communication modules, adopts a smartphone for data collection, data displaying, and remote communication. In this paper, authors modify this paradigm simplifying the wearables (e.g., relying only on simple analog front ends and communication interfaces) and exploiting the (relatively large) computational capability of the smartphone, not only for implementing gateway features but also for processing raw biosignals as well. Several experiments verify the feasibility of the proposed approach and demonstrate that 'local' biosensor virtualization is possible, expanding possibilities of mHealth. In particular, tests have been carried out to evaluate the performance of hearth rate computation and respiratory rate virtual sensor, starting from a single-lead electrocardiogram signal. 

  • 43.
    De Angelis, Alessio
    et al.
    University of Perugia, Perugia, Italy.
    Carbone, Paolo
    University of Perugia, Perugia, Italy.
    Sisinni, Emiliano
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology. University of Brescia, Brescia, Italy.
    Flammini, Alessandra
    University of Brescia, Brescia, Italy.
    Performance Assessment of Chirp-Based Time Dissemination and Data Communications in Inductively Coupled Links2017In: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 66, no 9, p. 2474-2482, article id 7930481Article in journal (Refereed)
    Abstract [en]

    Advantages of inductively coupled links for short-range communications are well known. Recently, they gained popularity as a viable solution for wireless power transmission. Interesting to notice that data communication capability is required as well, mainly for coordinating the transfer process. In this paper, the authors address the use of chirp signaling over inductively coupled links for both time dissemination and data communications. Such an approach extends field of applications, including data acquisition and instrumentation that are used in industrial automation. The effectiveness of the proposed approach is verified with extensive simulations and using a proof-of-concept prototype. Despite the prototype simplicity, jitter on the synchronizing reference signal is in the order of few microseconds and the bit error rate, over a short distance, is negligible.

  • 44.
    Dibo, Alexandra
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Challenges when making extensive changes to software processes: A case study on a software development department at Scania CV AB2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Organizations go through a variety of different change processes during their life time, and many of these are necessary for the organizations to maintain their competitiveness. However, a large part of change efforts never achieve their goals and about 70 percent of all change efforts are considered to be unsuccessful. A reason for the high percentage of failures is the inability to deal with the challenges that often arises in connection with the change process. In order for the change effort to be successful it is therefore crucial to be prepared and knowing how to identify and handle the challenges and resistance that may arise during the change process.

    The aim of the study has been to identify the challenges with extensive change efforts in software development organizations. Two extensive changes, (1) changing the software itself by making the software structure modular and (2) changing the software development process by adapting agile methods, at a software development department at Scania CV AB has been used as a case study.

    An overall fear and resistance towards extensive changes was identified. In addition, four main challenges were identified with the first change; difficulties with the software development process, lack of vision and communication from management, fear and uncertainty, and lack of resources and tools. Two challenges were identified with the second change; that it was time consuming and lack of resources and tools.

    The difficulties with the software development process showed that the major challenge with the modular software structure was maintaining it. However, the remaining challenges have previously been identified in several studies and could all be related to being causes of resistance.

    Also, a comparison between the two changes were made to identify similarities and differences between them. This was made to further understand if the difference between the changes could be related to the challenges. The comparison indicates that a change effort with a clear vision, good communication and management involvement is less likely to encounter challenges.

  • 45.
    Dima, Elijs
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Multi-Camera Light Field Capture: Synchronization, Calibration, Depth Uncertainty, and System Design2018Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The digital camera is the technological counterpart to the human eye, enabling the observation and recording of events in the natural world. Since modern life increasingly depends on digital systems, cameras and especially multiple-camera systems are being widely used in applications that affect our society, ranging from multimedia production and surveillance to self-driving robot localization. The rising interest in multi-camera systems is mirrored by the rising activity in Light Field research, where multi-camera systems are used to capture Light Fields - the angular and spatial information about light rays within a 3D space. 

    The purpose of this work is to gain a more comprehensive understanding of how cameras collaborate and produce consistent data as a multi-camera system, and to build a multi-camera Light Field evaluation system. This work addresses three problems related to the process of multi-camera capture: first, whether multi-camera calibration methods can reliably estimate the true camera parameters; second, what are the consequences of synchronization errors in a multi-camera system; and third, how to ensure data consistency in a multi-camera system that records data with synchronization errors. Furthermore, this work addresses the problem of designing a flexible multi-camera system that can serve as a Light Field capture testbed.

    The first problem is solved by conducting a comparative assessment of widely available multi-camera calibration methods. A special dataset is recorded, giving known constraints on camera ground-truth parameters to use as reference for calibration estimates. The second problem is addressed by introducing a depth uncertainty model that links the pinhole camera model and synchronization error to the geometric error in the 3D projections of recorded data. The third problem is solved for the color-and-depth multi-camera scenario, by using a proposed estimation of the depth camera synchronization error and correction of the recorded depth maps via tensor-based interpolation. The problem of designing a Light Field capture testbed is addressed empirically, by constructing and presenting a multi-camera system based on off-the-shelf hardware and a modular software framework.

    The calibration assessment reveals that target-based and certain target-less calibration methods are relatively similar at estimating the true camera parameters. The results imply that for general-purpose multi-camera systems, target-less calibration is an acceptable choice. For high-accuracy scenarios, even commonly used target-based calibration approaches are insufficiently accurate. The proposed depth uncertainty model is used to show that converged multi-camera arrays are less sensitive to synchronization errors. The mean depth uncertainty of a camera system correlates to the rendered result in depth-based reprojection, as long as the camera calibration matrices are accurate. The proposed depthmap synchronization method is used to produce a consistent, synchronized color-and-depth dataset for unsynchronized recordings without altering the depthmap properties. Therefore, the method serves as a compatibility layer between unsynchronized multi-camera systems and applications that require synchronized color-and-depth data. Finally, the presented multi-camera system demonstrates a flexible, de-centralized framework where data processing is possible in the camera, in the cloud, and on the data consumer's side. The multi-camera system is able to act as a Light Field capture testbed and as a component in Light Field communication systems, because of the general-purpose computing and network connectivity support for each sensor, small sensor size, flexible mounts, hardware and software synchronization, and a segmented software framework. 

  • 46.
    Dima, Elijs
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Gao, Yuan
    Institute of Computer Science, Christian-Albrechts University of Kiel, Germany.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Olsson, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Koch, Reinhard
    Institute of Computer Science, Christian-Albrechts University of Kiel, Germany.
    Esquivel, Sandro
    Institute of Computer Science, Christian-Albrechts University of Kiel, Germany.
    Estimation and Post-Capture Compensation of Synchronization Error in Unsynchronized Multi-Camera SystemsManuscript (preprint) (Other academic)
  • 47.
    Dima, Elijs
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Olsson, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Modeling Depth Uncertainty of Desynchronized Multi-Camera Systems2017In: 2017 International Conference on 3D Immersion (IC3D), IEEE, 2017Conference paper (Refereed)
    Abstract [en]

    Accurately recording motion from multiple perspectives is relevant for recording and processing immersive multi-media and virtual reality content. However, synchronization errors between multiple cameras limit the precision of scene depth reconstruction and rendering. In order to quantify this limit, a relation between camera de-synchronization, camera parameters, and scene element motion has to be identified. In this paper, a parametric ray model describing depth uncertainty is derived and adapted for the pinhole camera model. A two-camera scenario is simulated to investigate the model behavior and how camera synchronization delay, scene element speed, and camera positions affect the system's depth uncertainty. Results reveal a linear relation between synchronization error, element speed, and depth uncertainty. View convergence is shown to affect mean depth uncertainty up to a factor of 10. Results also show that depth uncertainty must be assessed on the full set of camera rays instead of a central subset.

  • 48.
    Dima, Elijs
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Olsson, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Kjellqvist, Martin
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Litwic, Lukasz
    Ericsson AB.
    Zhang, Zhi
    Ericsson AB.
    Rasmusson, Lennart
    Observit AB.
    Flodén, Lars
    Observit AB.
    LIFE: A Flexible Testbed For Light Field Evaluation2018Conference paper (Refereed)
    Abstract [en]

    Recording and imaging the 3D world has led to the use of light fields. Capturing, distributing and presenting light field data is challenging, and requires an evaluation platform. We define a framework for real-time processing, and present the design and implementation of a light field evaluation system. In order to serve as a testbed, the system is designed to be flexible, scalable, and able to model various end-to-end light field systems. This flexibility is achieved by encapsulating processes and devices in discrete framework systems. The modular capture system supports multiple camera types, general-purpose data processing, and streaming to network interfaces. The cloud system allows for parallel transcoding and distribution of streams. The presentation system encapsulates rendering and display specifics. The real-time ability was tested in a latency measurement; the capture and presentation systems process and stream frames within a 40 ms limit.

  • 49.
    Ding, Yuxia
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Internet of Things: Quantitative Evaluation on Microsoft Azure IoT Suite2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Internet of Things (IoT) is rapidly gaining ground in our daily life. There is a trend that the number of devices and data increases rapidly in the future. Meanwhile, IoT platforms are emerging to enable people conveniently deal with the IoT and these huge amount of data and devices. Therefore, the goal in this paper is to perform a quantitative evaluation on Microsoft Azure, one of the IoT platform, about its advantages and disadvantages under press to determine if Azure IoT is fit for future IoT. In order to reach this goal, Azure IoT Hub is used as a bridge to connect and manage lots of IoT devices which send and receive huge amount of data. .NET is used to simulate devices and connect them to the IoT Hub. The two-way communication from sensor to cloud and from cloud to actuator is implemented through MQTT protocol. This paper makes measurements on three metrics including response time from sensor sending messages to actuator receiving messages, scalability and cost and analyzes them in detail. Besides, the analysis is also made in a specific scenario which has high demand on sensor update to see how Azure IoT performs. Finally, conclusion is made on Microsoft Azure IoT's advantages and disadvantages under stress.

  • 50.
    Edin, Andreas
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Autentisering med OAuth 2.0 i SiteVision: Jämförelse mellan Java Portlets och WebApps2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this project has been to explore alternative technical solutions for making own extensions in the CMS SiteVision. The purpose of these extensions is to retrieve data from an external API (Office 365) which requires OAuth 2.0 authentication. Additional, the alternative technical solutions have been evaluated and compared. The comparisons have been made based on criteria developed through interviews with professional IT-consultants. The purpose of the project has been to contribute to more efficient digitization, integration and individualization of datasystems. Within the project, an applied example (POC) has been created to show examples of how the technology can be used. In this example, Java Portlets have been used to implement the above functionality. WebApps in SiteVision have also been studied since this technology is an alternative to Java Portlets. The survey shows that it is fully possible to create a separate extension in SiteVision that performs authentication with OAuth 2.0 and then uses it to retrieve data from an external API. The results from the comparison between the two different Java Portlets and WebApps technologies show that there are pros and cons of each technique. The alternatives studied where comparable in performance. Individual circumstances can dictate which alternative is best.

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