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  • 1.
    Abdulridha, Aya
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Albu-Jaafer, Ali
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Problem identification for the delivery system for document and errand management in an IT company: A qualitative case study an IT firm2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In today's society, many IT organizations have strived to implement system development to improve and streamline information management in an effort to streamline the entire organization. The first step in system development is to identify the problems experienced by the company. This study focuses on studying delivery systems at IT companies in order to identify problems and quality shortcomings in that system. The delivery system is used daily by employees at the fall company. It was noted that several problems have arisen when the system is not automated. Employees have different problems that they want to avoid. For example, employees must enter manually to change what has been generated by the system. This leads to waste times and increases the risk of failure. Research in the areas of system development and process development stresses the importance of developing or improving IT processes to achieve the required quality. The study has been conducted by observing and interviewing employees who work with the delivery system. The results of this study present three major problems that the system has today. These are installation guide, system usability and requirement specification. The Installation Wizard is a document that consists of all modules to be installed at the customer for the version to be released along with other necessary information about the deliveries or modules. This document is not generated by the system today but is manually created by the employees. This requires a lot of manual work and time to check and make sure they have got them all. Regarding the second issue, the current system lacks some features that make usability very complex and that takes time to learn how it works. Finally, the company has no clear requirement management process, which means that the company delivers a module or service that does not meet its requirements and expectations. The study also represents solutions to address these issues.  

  • 2.
    Afram, Gabriel
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Genomsökning av filsystem för att hitta personuppgifter: Med Linear chain conditional random field och Regular expression2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The new General Data Protection Regulation (GDPR) Act will apply to all companies within the European Union after 25 May. This means stricter legal requirements for companies that in some way store personal data. The goal of this project is therefore to make it easier for companies to meet the new legal requirements. This by creating a tool that searches file systems and visually shows the user in a graphical user interface which files contain personal data. The tool uses Named entity recognition with the Linear chain conditional random field algorithm which is a type of supervised learning method in machine learning. This algorithm is used in the project to find names and addresses in files. The different models are trained with different parameters and the training is done using the stanford NER library in Java. The models are tested by a test file containing 45,000 words where the models themselves can predict all classes to the words in the file. The models are then compared with each other using the measurements of precision, recall and F-score to find the best model. The tool also uses Regular Expression to find emails, IP numbers, and social security numbers. The result of the final machine learning model shows that it does not find all names and addresses, but that can be improved by increasing exercise data. However, this is something that requires a more powerful computer than the one used in this project. An analysis of how the Swedish language is built would also need to be done to apply the most appropriate parameters for the training of the model.

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  • 3.
    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.

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  • 4.
    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.

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  • 5.
    Ahmad, Shabir
    et al.
    Jeju National University, Jeju, South Korea.
    Hussain, Ishfaq
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Fayaz, Muhammad
    Jeju National University, Jeju, South Korea.
    Kim, Do-Hyeun
    Jeju National University, Jeju, South Korea.
    A Distributed Approach towards Improved Dissemination Protocol for Smooth Handover in MediaSense IoT Platform2018In: Processes, ISSN 2227-9717, Vol. 6, no 5, article id 46Article in journal (Refereed)
    Abstract [en]

    Recently, the Internet has been utilized by many applications to convey time-sensitive messages. The persistently expanding Internet coverage and its easy accessibility have offered to ascend to a problem which was once regarded as not essential to contemplate. Nowadays, the Internet has been utilized by many applications to convey time-sensitive messages. Wireless access points have widely been used but these access points have limitations regarding area coverage. So for covering a wider space, various access points need to be introduced. Therefore, when the user moves to some other place, the devices expected to switch between access points. Packet loss amid the handovers is a trivial issue. MediaSense is an Internet of Things distributed architecture enabling the development of the IoT application faster. It deals with this trivial handover issue by utilizing a protocol called Distributed Context eXchange Protocol. However, this protocol is centralized in nature and also suffers in a scenario when both sender and receiver address change simultaneously. This paper presents a mechanism to deal with this scenario and presents a distributed solution to deal with this issue within the MediaSense platform. The proposed protocol improves dissemination using retransmission mechanism to diminish packet loss. The proposed protocol has been delineated with a proof of concept chat application and the outcomes have indicated a significant improvement in terms of packet loss.

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  • 6.
    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.

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  • 7.
    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.

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  • 8.
    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.
    Towards a generic compression solution for densely and sparsely sampled light field data2018In: Proceedings of 25TH IEEE International Conference On Image Processing, 2018, p. 654-658, article id 8451051Conference paper (Refereed)
    Abstract [en]

    Light field (LF) acquisition technologies capture the spatial and angular information present in scenes. The angular information paves the way for various post-processing applications such as scene reconstruction, refocusing, and synthetic aperture. The light field is usually captured by a single plenoptic camera or by multiple traditional cameras. The former captures a dense LF, while the latter captures a sparse LF. This paper presents a generic compression scheme that efficiently compresses both densely and sparsely sampled LFs. A plenoptic image is converted into sub-aperture images, and each sub-aperture image is interpreted as a frame of a multiview sequence. In comparison, each view of the multi-camera system is treated as a frame of a multi-view sequence. The multi-view extension of high efficiency video coding (MVHEVC) is used to encode the pseudo multi-view sequence.This paper proposes an adaptive prediction and rate allocation scheme that efficiently compresses LF data irrespective of the acquisition technology used.

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  • 9.
    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, 2018, article id 8478611Conference 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.

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  • 10.
    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.

  • 11.
    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: OPTICS, PHOTONICS, AND DIGITAL TECHNOLOGIES FOR IMAGING APPLICATIONS V Proceedings of SPIE - The International Society for Optical Engineering, SPIE - International Society for Optical Engineering, 2018, Vol. 10679, article id 106790MConference 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.

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  • 12.
    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.

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  • 13.
    Ahmad, Waqas
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Vagharshakyan, Suren
    Tampere Univ Technol, Korkeakoulunkatu 10, Tampere 33720, Finland..
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Gotchev, Atanas
    Tampere Univ Technol, Korkeakoulunkatu 10, Tampere 33720, Finland..
    Bregovic, Robert
    Tampere Univ Technol, Korkeakoulunkatu 10, Tampere 33720, 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 Compression2018In: 2018 DATA COMPRESSION CONFERENCE (DCC 2018) / [ed] Bilgin, A Marcellin, MW SerraSagrista, J Storer, JA, IEEE, 2018, p. 396-396Conference paper (Refereed)
  • 14.
    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)
  • 15.
    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 (degree of Bachelor), 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.

  • 16.
    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.

  • 17.
    Allison, Robert S.
    et al.
    York University, Centre for Vision Research, Toronto, Canada.
    Brunnström, Kjell
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology. RISE AB (Acreo).
    Chandler, Damon M.
    Shizuoka University, Hamamatsu, Shizuoka, Japan.
    Colett, Hannah R.
    Intel Corp., Santa Clara, California, United States.
    Corriveau, Philip J.
    Intel Corp., Santa Clara, California, United States.
    Daly, Scott
    Dolby Laboratories Inc., Sunnyvale, California, United States.
    Goel, James
    Qualcomm Technologies, Inc., Display Video Processing Group, Markham, Canada.
    Long, Juliana Y.
    Intel Corp., Santa Clara, California, United States.
    Wilcox, Laurie M.
    York University, Centre for Vision Research, Toronto, Canada.
    Yaacob, Yusizwan M.
    Shizuoka University, Hamamatsu, Shizuoka, Japan.
    Yang, Shun-nan
    Pacific University, Forest Grove, Oregon, United States.
    Zhang, Yi
    Xi’an Jiaotong University, School of Electronic and Information Engineering, Xi’an, China.
    Perspectives on the definition of visually lossless quality for mobile and large format displays2018In: Journal of Electronic Imaging (JEI), ISSN 1017-9909, E-ISSN 1560-229X, Vol. 27, no 5, p. 1-23, article id 053035Article in journal (Refereed)
    Abstract [en]

    Advances in imaging and display engineering have given rise to new and improved image and videoapplications that aim to maximize visual quality under given resource constraints (e.g., power, bandwidth).Because the human visual system is an imperfect sensor, the images/videos can be represented in a mathematicallylossy fashion but with enough fidelity that the losses are visually imperceptible—commonly termed“visually lossless.” Although a great deal of research has focused on gaining a better understanding ofthe limits of human vision when viewing natural images/video, a universally or even largely accepted definitionof visually lossless remains elusive. Differences in testing methodologies, research objectives, and targetapplications have led to multiple ad-hoc definitions that are often difficult to compare to or otherwise employ inother settings. We present a compendium of technical experiments relating to both vision science and visualquality testing that together explore the research and business perspectives of visually lossless image quality,as well as review recent scientific advances. Together, the studies presented in this paper suggest that a singledefinition of visually lossless quality might not be appropriate; rather, a better goal would be to establish varyinglevels of visually lossless quality that can be quantified in terms of the testing paradigm.

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  • 18.
    Alsmo, Ludvig
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Bärlund, Jonathan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Nyttomaximering vid eleffektbrist på lokalnätet: En objektprioritering i en simuleringsansatts2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this study was to study the Styrel concept as an approach to identify electricity users and prioritize them in the event of a power shortage on a power grid. The study has examined and investigated how the priorities of different electricity users go to, how the benefits of manual disconnection change according to the decision makers' different priorities and how interaction between different local networks affects total utility. The features of a community on a local area, also called objects, are divided into eight priority classes depending on the function of the objects. The area for this study has been decision management. The study has been conducted using results from previous studies and theories on decision analysis as the basis for constructing a simulator that simulates how the power of a power failure changes for a local area dependent on the extent of the electricity supply (capacity). The study's findings have shown that prioritization of electricity supply line with higher priority classes should be prioritized than an electricity supply line with lower priority classes. This is also the result of previous studies. On the other hand, the study has shown that the fixed asset for an electricity supply line with lower priority objects is higher than an electricity supply line with higher priority objects, but with less benefit, priority should be given to the electricity supply line of higher priority objects. This study has thus resulted in the fact that electricity supply lines should be prioritized after the benefit if a decision maker is aware of the extent of the deficiency. Current collaboration between local networks showed that this could be dependent on the factors: distance, risk profile of decision makers and change of benefit through collaboration.  

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  • 19.
    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)
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  • 20.
    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).

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  • 21.
    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 (degree of Bachelor), 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.

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  • 22.
    Andersson, Lena
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Tillgängliggörande av sekretessbelagd arkivinformation om enskilda personer: Rörande hälsa och sociala förhållanden2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den här uppsatsens fokus ligger på lagstiftningen och hanteringen av sekretessbelagd information om enskilda personer gällande hälsa och sociala förhållanden. Att tolka lagar är inte lätt och vilket ansvar vilar på arkiven kring utlämnande av sådana handlingar. Med studien vill jag få fram hur arkiven praktiskt arbetar med detta för att få fram ett underlag om hur man kan tänka kring hanteringen vid utlämnande av sådana uppgifter. Appraisalmetoden som använts och sekretessen påverkar vad som finns tillgängligt från arkiven. Urvalet av det som bevaras av handlingar speciellt rörande barn som har kommit i kontakt med Socialstyrelsen har kritiserats då det framkommit att dessa har gallrats för mycket utifrån de förfrågningar som kommit till arkiven om utlämnande av dessa då de inte funnits. För att få fram detta har jag använt mig av två metoder där det ena är litteraturstudier och den andra är intervjuer av två arkivinstitutioner som har hand om sådana handlingar, ett kommunarkiv och ett landstingsarkiv. Resultatet av studien har blivit ett underlag till en vägledning utifrån rådande lagstiftning där hanteringen och frågor som kan vara bra att ha med sig för att kunna avgöra om en handling kan lämnas ut eller inte. Det har också kommit fram att sekretesstiden kan ha blivit för kort i Sverige med sina 70 år jämfört med till exempel Norge och Kanada som har 80 år och mer beroende på handlingstypen. Detta utifrån att vi lever längre än tidigare och lagen borde anpassas efter det.

     

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  • 23.
    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 (degree of Bachelor), 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.

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  • 24.
    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. 

  • 25.
    Astner, Thomas
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Forest thinning in VR: A VR application with the theme of forest thinning2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose with this project was to create a virtual reality game were the users should be able to carry out a thinning. The main goals are to use real forests terrains as terrain models in the game, the GameObjects and the teleportation system in the application should be able to handle changing terrains and the application should not cause virtual reality sickness. The application has been developed with the help of the game engine Unity and plugins from Unitys own asset store. User tests and measurements will be carried out in order to evaluate if the game causes virtual reality sickness or not. The results shows that it is possible to use real forests terrains and that the solution is suited for this application. The downside is that in order to use real life terrains several steps has to be taken and that the terrain object has to be designed manually. It also shows that the GameObjects and the Teleportation system has been implemented in a way so they can handle changing terrains. Furthermore it shows that some of the functionalities of the application could be improved, especially the scoring system. The users tests and the measurements showed that the application isn't causing virtual reality sickness but it also showed that the users feels like there are things missing in the application

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  • 26.
    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.

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  • 27.
    Barac, Filip
    et al.
    Ericsson AB.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Zhang, Tingting
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Sisinni, Emiliano
    University of Brescia.
    Error Manifestation in Industrial WSN Communication and Guidelines for Countermeasures2017In: Wireless Sensor Systems for Extreme Environments: Space, Underwater, Underground and Industrial / [ed] H. F. Rashvand and A. Abedi, John Wiley & Sons, 2017Chapter in book (Refereed)
  • 28.
    Bartosch, Nadine
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Correspondence-based pairwise depth estimation with parallel acceleration2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report covers the implementation and evaluation of a stereo vision corre- spondence-based depth estimation algorithm on a GPU. The results and feed- back are used for a Multi-view camera system in combination with Jetson TK1 devices for parallelized image processing and the aim of this system is to esti- mate the depth of the scenery in front of it. The performance of the algorithm plays the key role. Alongside the implementation, the objective of this study is to investigate the advantages of parallel acceleration inter alia the differences to the execution on a CPU which are significant for all the function, the imposed overheads particular for a GPU application like memory transfer from the CPU to the GPU and vice versa as well as the challenges for real-time and concurrent execution. The study has been conducted with the aid of CUDA on three NVIDIA GPUs with different characteristics and with the aid of knowledge gained through extensive literature study about different depth estimation algo- rithms but also stereo vision and correspondence as well as CUDA in general. Using the full set of components of the algorithm and expecting (near) real-time execution is utopic in this setup and implementation, the slowing factors are in- ter alia the semi-global matching. Investigating alternatives shows that results for disparity maps of a certain accuracy are also achieved by local methods like the Hamming Distance alone and by a filter that refines the results. Further- more, it is demonstrated that the kernel launch configuration and the usage of GPU memory types like shared memory is crucial for GPU implementations and has an impact on the performance of the algorithm. Just concurrency proves to be a more complicated task, especially in the desired way of realization. For the future work and refinement of the algorithm it is therefore recommended to invest more time into further optimization possibilities in regards of shared memory and into integrating the algorithm into the actual pipeline.

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  • 29.
    Baswade, Anand M.
    et al.
    Indian Institute of Technology, Hyderabad, India.
    Beltramelli, Luca
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology. Mid Sweden University.
    Antony, Franklin A.
    Indian Institute of Technology, Hyderabad, India.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Reddy Tamma, Bheemarjuna
    Indian Institute of Technology, Hyderabad, India.
    Guntupalli, Lakshmikanth
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Modelling and Analysis of Wi-Fi and LAA Coexistence with Priority Classes2018In: 2018 14th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), IEEE, 2018Conference paper (Refereed)
    Abstract [en]

    The Licensed Assisted Access (LAA) is shown asa required technology to avoid overcrowding of the licensedbands by the increasing cellular traffic. Proposed by 3GPP,LAA uses a Listen Before Talk (LBT) and backoff mechanismsimilar to Wi-Fi. While many mathematical models have beenproposed to study the problem of the coexistence of LAAand Wi-Fi systems, few have tackled the problem of QoSprovisioning, and in particular analysed the behaviour of thevarious classes of priority available in Wi-Fi and LAA. Thispaper presents a new mathematical model to investigate theperformance of different priority classes in coexisting Wi-Fi andLAA networks. Using Discrete Time Markov Chains, we modelthe saturation throughput of all eight priority classes used byWi-Fi and LAA. The numerical results show that with the 3GPPproposed parameters, a fair coexistence between Wi-Fi and LAAcannot be achieved. Wi-Fi users in particular suffer a significantdegradation of their performance caused by the collision withLAA transmissions which has a longer duration compared toWi-Fi transmissions.

  • 30.
    Beltramelli, Luca
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Guntupalli, Lakshmikanth
    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.
    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.
    Modeling of Enhanced Distributed Channel Access with Station Grouping: A Throughput Analysis2018In: Proc. IEEE 88th Vehicular Technology Conference (VTC'18-fall), Chicago, USA, Aug. 2018., IEEE conference proceedings, 2018, article id 8690814Conference paper (Refereed)
    Abstract [en]

    Machine to Machine (M2M) communication networksare expected to connect a large number of power constrained devices in long range applications with differentquality of service (QoS) requirements. Medium access control with QoS support such as the Enhanced Distributed Channel Access (EDCA) defined by IEEE 802.11e provides traffic differentiation and corresponding priority classes, which guarantees QoSaccording to the needs of applications. In this paper, we employa station grouping mechanism for enhancing the scalability of EDCA to handle the massive number of access attempts expected in large M2M networks. Furthermore, we develop a discrete time Markov chain (DTMC) model to analyze the performance of EDCA with station grouping. Using the developed DTMC model, we calculate throughput for each access category as well as for different combinations of grouping and EDCA parameters. Thenumerical results show that the model can precisely reveal the behavior of EDCA mechanism. Moreover, it is demonstrated that employing the proposed grouping mechanism for EDCA increasesthe normalized throughput significantly for all classes of priority.

  • 31.
    Beltramelli, Luca
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Mahmood, Aamir
    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.
    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.
    Interference Modelling in a Multi-Cell LoRa System2018In: 2018 14th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), IEEE, 2018Conference paper (Refereed)
    Abstract [en]

    As the market for low-power wide-area network (LPWAN) technologies expands and the number of connected devices increases, it is becoming important to investigate the performance of LPWAN candidate technologies in dense deployment scenarios. In dense deployments, where the networks usually exhibit the traits of an interference-limited system, a detailed intra- and inter-cell interference analysis of LPWANs is required. In this paper, we model and analyze the performance of uplink communication of a LoRa link in a multi-cell LoRa system. To such end, we use mathematical tools from stochastic geometry and geometric probability to model the spatial distribution of LoRa devices. The model captures the effects of the density of LoRa cells and the allocation of quasi-orthogonal spreading factors (SF) on the success probability of the LoRa transmissions. To account for practical deployment of LoRa gateways, we model the spatial distribution of the gateways with a Poisson point process (PPP) and Matèrn hard-core point process (MHC). Using our analytical formulation, we find the uplink performance in terms of success probability and potential throughput for each of the available SF in LoRa’s physical layer. Our results show that in dense multi-cell LoRa deployment with uplink traffic, the intercell interference noticeably degrades the system performance.

  • 32.
    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%.

  • 33.
    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.

     

  • 34.
    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.

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  • 35.
    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 (degree of Bachelor), 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.

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  • 36.
    Blixt Myrsell, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Dynamiska Skript: Automatisering med Python2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Company X is an Internet Service Provider in need of automation. There are three IT technicians employed and as of right now they rely on scripts that automate everything from documentation to the company database to the basic configuration of the network switches that gets delivered to the customers. The company also provides customer support if that is included in the agreement and when the company grows, so does the workload. To minimize the time the employees have to spend to inform and support customers, the company wishes to create a web-based platform where the customers can help themselves. This project aims to create, test and evaluate a first draft of said platform, on which a customer should be able to log in and see information about their units and configure those units based on parameters set by the company. To accomplish this the programming language Python and its libraries and modules will be used. This project report covers the relevant theory and the work has been realized via the gathering of project requirements, pseudocode and flowcharts, coding and testing, and evaluation. Furthermore a discussion is had regarding the ethics of automation. The study has shown that Python and its libraries is well suited to accomplish automation according to the company’s needs.

  • 37.
    Bondeson, Emelie
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Essie - Få koll på vad maten innehåller2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Rapporten kommer beskriva faserna planering, implementering och resultat av en webbapplikation som näringsberäknar recept. Webbapplikationens syfte är att skapa medvetenhet över effekten och konsekvenserna som våra matval har över oss. Den är inte riktad till den enskilda personen, utan snarare till storkök som exempelvis skolkök. Applikationen är skriven med i HTML, CSS, PHP, MySQL, AJAX och jQuery. För att underlätta designarbetet används ramverket Twitter Bootstrap. Rapporten beskriver de olika delarna av utvecklandet i applikationen, från databasdesign till funktioner för att lägga till och radera recept och råvaror. Resultatet blev en webbapplikation som näringsberäknar recepten man skapar. Man kan söka efter, sortera och filtrera recept. De enskilda receptsidorna innehåller näringsberäkning per portion, som man sedan kan skriva ut i en utskriftsvänlig version.

  • 38.
    Borgenstrand, Markus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Network automation – the power of Ansible2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report discusses network automation primarily with Ansible. Ansible is a software from Red Hat that can be used for network automation. The report also goes through YAML which is a standardized way of exchanging data, Jinja2 that is a templating language, Python as well as the security with Ansible. The report also goes through why network automation is needed as well as how much time might be saved with Ansible. Ansible ships with modules for Cisco IOS such as ios_config and ios_command and for Cisco ASA asa_config, asa_command and asa_acl as well as many other modules for Arista, Juniper and for other vendors. Ansible can use new APIs by creating new modules for handling that particular API, which means that the only change needed in the playbooks is to change the module name. Ansible can handle NETCONF API using the netconf_config module or various Juniper modules. Ansible is used in this report to perform certain tasks such as to adding VLAN's, close ports on ASA's, audit network devices configuration as well as to create network diagram using the information from CDP. Ansible can be made as secure as manually doing the tasks except that Ansible can do it faster and more consistently.  For connecting to normal Linux servers Ansible uses OpenSSH which is a default SSH client on most Linux systems and for connecting to network devices it uses Paramiko. The security in Ansible depends on SSH and may or may not have passwords stored locally, Ansible can be as secure as the administrator wants it to be such as using RSA key-pair to authenticate, using vault encrypted credentials or asking the administrator about which username and password to use. Using Ansible network automation can save time, the amount saved depends on what is being done, how many devices it is doing it on as well as how the playbook is written.

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  • 39.
    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 Advanced level (degree of Master (One Year)), 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.

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  • 40.
    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)
  • 41.
    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)
  • 42.
    Bosk, Daniel
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology. KTH Royal Institute of Technology, Stockholm.
    Rodríguez-Cano, Guillermo
    KTH Royal Institute of Technology, Stockholm.
    Greschbach, Benjamin
    KTH Royal Institute of Technology, Stockholm.
    Buchegger, Sonja
    KTH Royal Institute of Technology, Stockholm.
    Applying privacy-enhancing technologies: One alternative future of protests2018In: Protests in the Information Age: Social Movements, Digital Practices and Surveillance / [ed] Lucas Melgaço, Jeffrey Monaghan, Taylor and Francis , 2018, p. 73-94Chapter in book (Other academic)
    Abstract [en]

    While current technologies, such as online social networks, can facilitate coordination and communication for protest organization, they can also endanger political activists when the control over their data is ceded to third parties. For technology to be useful for activism, it needs to be trustworthy and protect the users’ privacy; only then can it be viewed as a potential improvement over more traditional, offline methods. Here, we discuss a selection of such privacy-enhancing technologies from a Computer Science perspective in an effort to open a dialogue and elicit input from other perspectives. 

  • 43.
    Boström, Lena
    et al.
    Mid Sweden University, Faculty of Human Sciences, Department of Education.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Karlsson, Håkan
    Mid Sweden University, Faculty of Human Sciences, Department of Education.
    Sundgren, Marcus
    Mid Sweden University, Faculty of Human Sciences, Department of Education.
    Andersson, Mattias
    Olsson, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Åhlander, Jimmy
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Digital visualisering i skolan: Mittuniversitetets slutrapport från förstudien2018Report (Other academic)
    Abstract [sv]

    Den här studiens syfte har varit tvåfaldigt, nämligen att testa alternativa lärmetoder via ett digitalt läromedel i matematik i en kvasiexperimentell studie samt att tillämpa metoder av användarupplevelser för interaktiva visualiseringar, och därigenom öka kunskapen kring hur upplevd kvalitet beror på använd teknik. Pilotstudien sätter också fokus på flera angelägna områden inom skolutveckling både regionalt och nationellt samt viktiga aspekter när det gäller kopplingen teknik, pedagogik och utvärderingsmetoder inom “den tekniska delen”. Det förra handlar om sjunkande matematikresultat i skolan, praktiknära skolforskning, stärkt digital kompetens, visualisering och lärande samt forskning om visualisering och utvärdering. Den senare svarar på frågor om vilka tekniska lösningar som tidigare använts och med vilket syfte har de skapats samt hur visualiseringar har utvärderats enligt läroböcker och i forskningslitteratur.

     

    När det gäller elevernas resultat, en av de stora forskningsfrågorna i studien, så fann vi inga signifikanta skillnader mellan traditionell undervisning och undervisning med visualiseringsläromedlet (3D). Beträffande elevers attityder till matematikmomentet kan konstateras att i kontrollgruppen för årskurs 6 förbättrades attityden signifikans, men inte i klass 8. Gällande flickors och pojkars resultat och attityder kan vi konstatera att flickorna i båda klasserna hade bättre förkunskaper än pojkarna samt att i årskurs 6 var flickorna mer positiva till matematikmomentet än pojkarna i kontrollgruppen. Därutöver kan vi inte skönja några signifikanta skillnader. Andra viktiga rön i studien var att provkonstruktionen inte var optimal samt att tiden för provgenomförande har stor betydelse när på dagen det genomfördes. Andra resultat resultaten i den kvalitativa analysen pekar på positiva attityder och beteenden från eleverna vid arbetet med det visuella läromedlet. Elevernas samarbete och kommunikation förbättrades under lektionerna. Vidare pekade lärarna på att med 3D-läromedlet gavs större möjligheter till att stimulera flera sinnen under lärprocessen. En tydlig slutsats är att 3D-läromedlet är ett viktigt komplement i undervisningen, men kan inte användas helt självt.

     

    Vi kan varken sälla oss till de forskare som anser att 3D-visualisering är överlägset som läromedel för elevers resultat eller till de forskare som varnar för dess effekter för elevers kognitiva överbelastning.  Våra resultat ligger mer i linje med de slutsatser Skolforskningsinstitutet (2017) drar, nämligen att undervisning med digitala läromedel i matematik kan ha positiva effekter, men en lika effektiv undervisning kan möjligen designas på andra sätt. Däremot pekar resultaten i vår studie på ett flertal störningsmoment som kan ha påverkat möjliga resultat och behovet av god teknologin och välutvecklade programvaror.

     

    I studien har vi analyserat resultaten med hjälp av två övergripande ramverk för integrering av teknikstöd i lärande, SAMR och TPACK. Det förra ramverket bidrog med en taxonomi vid diskussionen av hur väl teknikens möjligheter tagits tillvara av läromedel och i läraktiviteter, det senare för en diskussion om de didaktiska frågeställningarna med fokus på teknikens roll. Båda aspekterna är högaktuella med tanke på den ökande digitaliseringen i skolan.

     

    Utifrån tidigare forskning och denna pilotstudie förstår vi att det är viktigt att designa forskningsmetoderna noggrant. En randomisering av grupper vore önskvärt. Prestandamått kan också vara svåra att välja. Tester där personer får utvärdera användbarhet (usability) och användarupplevelse (user experience, UX) baserade på både kvalitativa och kvantitativa metoder blir viktiga för själva användandet av tekniken, men det måste till ytterligare utvärderingar för att koppla tekniken och visualiseringen till kvaliteten i lärandet och undervisningen. Flera metoder behövs således och det blir viktigt med samarbete mellan olika ämnen och discipliner.

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  • 44.
    Brandt, Nick
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    ChattyMe – En webbaserad chattapplikation2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med denna rapporten är att redovisa utvecklingen av chattapplikationen ChattyMe. Målet med projektet är att skapa en robust och högpresterande webbapplikation. Enligt undersökningar finns det stora brister i säkerheten på flertalet webbplatser, och därför är det extra viktigt och en hög prioritet att utveckla denna applikationen med stort fokus på säkerhet. För att kunna hantera den begränsade utvecklingstiden har en tidsplan med deadlines skapats som följs under hela utvecklingen. Det som kommer att ingå i applikationen är teknik som registrering och inloggning, chattrum och privata meddelanden medlemmar emellan. Teknologierna som kommer att användas till att utveckla applikationen är JavaScript-ramverket Angular för frontend och JavaScript server-ramverket Node.js för backend. Förutom Angular och Node.js kommer JavaScript-biblioteket Socket.io användas för uppdatering i realtid. Att utveckla effektivt är viktigt i ett tidsbegränsad projekt, och för att göra det krävs en optimal utvecklingsmiljö. I detta fallet har Jetbrains Webstorm använts för programmering, Google Chrome debugger för debugging, med Postman för API testning och detta har gjorts i Linux Ubuntu 17.10 operativsystem. Resultatet blev en funktionell, högpresterande och säker chattapplikation enligt tester.

  • 45.
    Brunnstrom, Kjell
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology. RISE AB Acreo.
    Barkowsky, Marcus
    Deggendorf Institute of Technology (DIT), University of Applied Sciences, Deggendorf.
    Statistical quality of experience analysis: on planning the sample size and statistical significance testing2018In: Journal of Electronic Imaging (JEI), ISSN 1017-9909, E-ISSN 1560-229X, Vol. 27, no 5, p. 053013-1-053013-11, article id 053013Article in journal (Refereed)
    Abstract [en]

    This paper analyzes how an experimenter can balance errors in subjective video quality tests betweenthe statistical power of finding an effect if it is there and not claiming that an effect is there if the effect is not there,i.e., balancing Type I and Type II errors. The risk of committing Type I errors increases with the number ofcomparisons that are performed in statistical tests. We will show that when controlling for this and at thesame time keeping the power of the experiment at a reasonably high level, it is unlikely that the number oftest subjects that are normally used and recommended by the International Telecommunication Union (ITU),i.e., 15 is sufficient but the number used by the Video Quality Experts Group (VQEG), i.e., 24 is more likelyto be sufficient. Examples will also be given for the influence of Type I error on the statistical significance ofcomparing objective metrics by correlation. We also present a comparison between parametric and nonparametricstatistics. The comparison targets the question whether we would reach different conclusions on the statisticaldifference between the video quality ratings of different video clips in a subjective test, based on thecomparison between the student T-test and the Mann–Whitney U-test. We found that there was hardly a differencewhen few comparisons are compensated for, i.e., then almost the same conclusions are reached. Whenthe number of comparisons is increased, then larger and larger differences between the two methods arerevealed. In these cases, the parametric T-test gives clearly more significant cases, than the nonparametrictest, which makes it more important to investigate whether the assumptions are met for performing a certaintest.

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  • 46.
    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.

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  • 47.
    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.

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  • 48.
    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, Mölndal.
    Quality Of Experience For A Virtual Reality Simulator2018In: IS and T International Symposium on Electronic Imaging Science and Technology 2018, 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).

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  • 49.
    Brunnström, Kjell
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology. Acreo Swedish ICT AB.
    Wang, Kun
    Acreo Swedish ICT AB.
    Tavakoli, Samira
    Universidad Politécnica de Madrid, Spain.
    Andrén, Börje
    Acreo Swedish ICT AB.
    Symptoms analysis of 3D TV viewing based on Simulator Sickness Questionnaires2017In: Quality and User Experience, ISSN 2366-0147, Vol. 2, no 1Article in journal (Refereed)
    Abstract [en]

    Stereoscopic 3D TV viewing puts different visual demands on the viewer compared to 2D TV viewing. Previous research has reported on viewers' fatigue and discomfort and other negative effects. This study is to investigate further how severe and what symptoms may arise from somewhat longish 3D TV viewing.

    The MPEG 3DV project is working on the next-generation video encoding standard and in this process, MPEG issued a call for proposal of encoding algorithms. To evaluate these algorithms a large scale subjective test was performed involving Laboratories all over the world[1, 2]. For the participating Labs, it was optional to administer a slightly modified Simulator Sickness Questionnaire (SSQ) before and after the test. One of the SSQ data sets described in this article is coming from this study. The SSQ data from the MPEG test is the largest data set in this study and also contains the longest viewing times. Along with the SSQ data from the MPEG test, we have also collected questionnaire data in three other 3D TV studies. We did two on the same 3D TV (passive film pattern retarder) as in the MPEG test, and one was using a projector system. As comparison SSQ data from a 2D video quality experiment is also presented. 

    This investigation shows a statistically significant increase in symptoms after viewing 3D TV primarily related to the visual or Oculomotor system. Surprisingly, 3D video viewing using projectors did not show this effect.

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  • 50.
    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.

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