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  • 1.
    Ali, Majid
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Improving the Adaptive Context Views and Evaluate Real-Time Performance2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The versatility and dimension of smart phone applications is   increasing at magnificent rate and getting more and more advanced in a level that could solve complicated real time tasks. One of the important factors for such advancement has been the powerful sensors embedded on a Smartphone devices and sensory networks. Moreover, Context and Context-awareness would have remained a myth without the advent of sensors. The objective of this thesis has been to contribute to the research work carried out under the MediaSense project. Accordingly, the ultimate purpose of the thesis has been to evaluate and study the feasibility of the adaptive context view proposed in MediaSense Platform. In precise words, the thesis has done three core tasks. Firstly, the theoretical presentation of related works and the significance of the research question have been discussed through various social applications. Secondly, a proof-of-concept application has been developed to simulate what has been proposed in the research work. Finally, Android application has been designed and implemented in order to evaluate and study the techniques presented in a practical scenario. Moreover, in the android application known as SundsvallBIGBuddies, we have used the extensions designed for the existing MediaSense platform. The impact of using Android app relaying on a continuous stream of context data has been presented using graphs and tables.  In order to study the impact we used smart phone and tablets from Samsung.

  • 2.
    Aloisi, Alessandro
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems. University of Bologna (Italy).
    Enabling communication between Wireless Sensor Networks and The Internet-of-Things: A CoAP communication stack2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The thesis focuses on enabling the communication between Wireless Sensor Networks and Internet-of-Things applications.  In order to achieve this goal, the first step has been to investigate the concept of the Internet-of-Things and then to understand how this scenario could be used to interconnect multiple Wireless Sensor Networks in order to develop context-aware applications which could handle sensor data coming from this type of network. 

    The second step was to design and implement a communication stack which enabled Wireless Sensor Networks to communicate with an Internet-of-Things platform. The CoAP protocol has been used as application protocol for the communication with the Wireless Sensor Networks. The solution has been developed in Java programming language and extended the sensor and actuator layer of the Sensible Things platform. 

    The third step of this thesis has been to investigate in which real world applications the developed solution could have been used. Next a Proof of Concept application has been implemented in order to simulate a simple fire detection system, where multiple Wireless Sensor Networks collaborate to send their temperature data to a control center. The last step was to evaluate the whole system, specifically the responsiveness and the overhead introduced by the developed communication stack.

  • 3.
    Amoura, Jonas
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Nätverksemulatorer: Nätverksemulering i utbildningssyfte2015Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    This is a project that deals with network emulators for training purposes, where everything is based on open-source applications. The goal of this project was to evaluate GNS3 and CORE emulators and answer the question, if and how they can be used in educational purposes for students and teachers. The study begins by briefly describing the various emulators available through open-source, where it was chosen to focus on the following network emulators IMUNES: Marionnet, Mininet, NetKit, GNS3 and CORE. The evaluation was conducted using a form, and GNS3 and CORE emulators run on a Linux-based operating systems to test all functions and various applications available within the tools. The results showed that both emulators work great to make use of open-source applications that can emulate router functions to emulate network topologies with different routing protocols such as RIP, OSPF and BGP. The evaluation also showed that both emulators are excellent tools to be used by people with minimal knowledge in programming, because of its user-friendly interface that helps one to build complex topologies using drag-and-drop functionality only. The conclusion of the study is that both emulators work well for educational purposes to develop network technology, router protocols and Linux skills for students, as well as to create a virtual environment to develop their skills with which they also can experiment with their skills. To install the network emulators GNS3 and CORE and related applications took about 30 minutes per tool, as well as taking GNS3 23 MB and Core 10MB hard disk space to be installed without any accessory applications.

    Why these two tools work well for training purposes is that both emulators has integrated support for a large numbers of applications and the use of simple user interface to emulate network environments. In addition, the tools are completely free to all students and teachers, therefore everyone have the same opportunities to access them. The report recommendation is to use the emulator CORE precisely because the utility has so many features integrated within itself, and it is such a simple tool to use.

  • 4. Andrén, Börje
    et al.
    Wang, Kun
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Brunnström, Kjell
    Characterizations of 3D TV: Active vs passive2012In: SID Symposium Digest of Technical Papers 2012, Blackwell Publishing Ltd , 2012, p. 137-140Conference paper (Refereed)
    Abstract [en]

    Two different techniques are dominating the 3D TV market today i.e. active shutter glasses and passive film patterned retarder. Both the techniques have their pros and cons. In this paper we compare these two types of 3D TV3D TV by evaluating them with respect to some important visual ergonomic parameters such as angle dependent cross talk, luminance levels, flicker and resolution.

  • 5.
    Anwar, Qaiser
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Imran, Muhammad
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    O'Nils, Mattias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Intelligence Partitioning as a Method for Architectural Exploration of Wireless Sensor Node2016In: Proceedings of the International Conference on Computational Science and Computational Intelligence (CSCI), 2016., IEEE Press, 2016, p. 935-940, article id 7881473Conference paper (Refereed)
    Abstract [en]

    Embedded systems with integrated sensing, processing and wireless communication are driving future connectivity concepts such as Wireless Sensor Networks (WSNs) and Internet of Things (IoTs). Because of resource limitations, there still exists a number of challenges such as low latency and energy consumption to realize these concepts to full potential. To address and understand these challenges, we have developed and employed an intelligence partitioning method which generates different implementation alternatives by distributing processing load across multiple nodes. The task-to-node mapping has exponential complexity which is hard to compute for a large scale system. Regarding this, our method provides recommendation to handle and minimize such complexity for a large system. Experiments on a use-case concludes that the proposed method is able to identify unfavourable architecture solutions in which forward and backword communication paths exists in task-to-node mapping. These solution can be avoided for further architectural exploration, thus limiting the space for architecture exploration of a sensor node.

  • 6.
    Aryefyev, Maksym
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    NAT traversal techniques for MediaSense open source platform2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis project concerns NAT traversal techniques and their application to P2P networking with regard to MediaSense platform. Since MediaSense open source platform, developed by Mid Sweden University, utilizes the benefits of P2P networking, it also suffers from the drawbacks provided by NAT. The issue of NAT traversal is not trivial due to the fact that the behavior of NAT devices is not standardized and vendors are free to provide their own implementations. The common knowledge is, that at least four main types of NATs exist, differing in the filtering and mapping algorithms employed. NAT traversal techniques vary accordingly. No single technique can handle all the cases. Most of the techniques can handle up to three main types of NAT. The last type is usually used in large corporate networks and is called the Symmetric NAT. The most viable, and basically the only available technique for its traversal, is data relaying. This thesis builds a NAT traversal module for the MediaSense platform. The main purpose of this module is to provide seamless NAT traversal capabilities to the platform. The module does this in several steps: UPnP enabled device discovery, NAT type determination and data relaying via the proxy. Firstly the module attempts to discover the presence of a UPnP enabled Internet Gateway Device on the network. If such a device is present on the network, a port mapping can be created, making the node located behind NAT accessible from the public Internet. If a UPnP enabled device was not found, the module will try to determine the type of NAT used. Based on the type of NAT used, the module can transit to either the proxy mode or request assistance of the STUN server to keep the created mapping alive. The resulting chapters provide the reader with the output produced by each step, conclusions the author has made while working on this project and some general ideas on future work within the subject.

  • 7.
    Atif, Sohaib
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems. Mid sweden University.
    Cooperative diversity and downlink power control using PARPS with application to LTE services (eMBMS and CoMP)2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Mobile devices and their applications are continuing to develop and the more advanced they are, the more they require high data ranges and the more they demand of the available wireless communication networks. At present, LTE (Long Term Evolution) is a good solution as it provides the users of mobile devices with a good throughput and a low latency. In the future, the two most important aspects for end users will be system spectral efficiency and system power controlling. This thesis deals with LTE downlink spectral efficiency and power controlling. The thesis will show how, by using IP multicasting for the LTE downlink, the base station is able to provide the necessary data through a significantly smaller spectrum and, additionally, how cooperative diversity, i.e. the cooperation between several base stations, can improve or even maximise the total network channel capacity, regardless of bandwidth size. A Packet and Resource Plan Scheduling algorithm (PARPS) is used to schedule the transmissions, and the results are calculated in MATLAB. By this means it is possible to analyse the efficiency of the spectrum management, the coverage probability and the power controlling for the different transmitters used for the LTE downlink.The LTE downlink scheme is simulated in Matlab for different numbers of transmitters (2-3). IP multicasting over the LTE downlink manages to transmit the same amount of data using less transmission power (50- 66.6%) with a better system spectral efficiency.

  • 8.
    Barkland, Lars-Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science.
    Norder, Kim
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science.
    En studie av Scrum för två personer och utveckling av mobilt gränssnitt2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A big portion of software development is the method which controls the flow ofthe creative process. Thru experience it has been shown how a lack oforganisation can have a profoundly negative effect on the development workand finally on the product itself. We take the Scrum method in a two-man formand analyze how the a small-scale version effects the roles, artefacts andactivities associated with the original Scrum method. The result of the workusing a small scale Scrum is presented along with the changes that have beendone during the work. The result and the final discussion show a positive effecton using a structured development method.Lately the use of small screen devices and their use of the Internet has widelyincreased . With this change in user interface comes new challenges designing aWeb handling a wide variety of user devices. In the process of developing aweb application techniques for small-screen interfaces was analyzed from thewhere Responsive Design was found to be the best choice concidering relevantlimitations. Design principals from the concept of Responsive Design isanalyzed and applied.

  • 9. Barkowsky, M.
    et al.
    Wang, Kun
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Cousseau, R.
    Brunnstrom, K.
    Olsson, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Le Callet, P.
    Subjective quality assessment of error concealment strategies for 3DTV in the presence of asymmetric transmission errors2010In: Proceedings of 2010 IEEE 18th International Packet Video Workshop (PV, 2010, p. 193-200Conference paper (Refereed)
    Abstract [en]

    The transmission of 3DTV sequences over packet based networks may result in degradations of the video quality due to packet loss. In the conventional 2D case, several different strategies are known for extrapolating the missing information and thus concealing the error. In 3D however, the residual error after concealment of one view might leads to binocular rivalry with the correctly received second view. In this paper, three simple alternatives are presented: frame freezing, a reduced playback speed, and displaying only a single view for both eyes, thus effectively switching to 2D presentation. In a subjective experiment the performance in terms of quality of experience of the three methods is evaluated for different packet loss scenarios. Error-free encoded videos at different bit rates have been included as anchor conditions. The subjective experiment method contains special precautions for measuring the Quality of Experience (QoE) for 3D content and also contains an indicator for visual discomfort. The results indicate that switching to 2D is currently the best choice but difficulties with visual discomfort should be expected even for this method.

  • 10.
    Barkowsky, Marcus
    et al.
    LUNAM Université, Université de Nantes, IRCCyN UMR CNRS 6597, France .
    Li, Jing
    LUNAM Université, Université de Nantes, IRCCyN UMR CNRS 6597, France .
    Han, Taehwan
    Youn, Sungwook
    Ok, Jiheon
    Lee, Chulhee
    Hedberg, Christer
    Dept. of Netlab, Acreo Swedish ICT AB, Sweden .
    Ananth, Indirajith Vijai
    Dept. of Netlab, Acreo Swedish ICT AB, Sweden .
    Wang, Kun
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science. Dept. of Netlab, Acreo Swedish ICT AB, Sweden .
    Brunnström, Kjell
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems. Dept. of Netlab, Acreo Swedish ICT AB, Sweden .
    Le Callet, Patrick
    LUNAM Université, Université de Nantes, IRCCyN UMR CNRS 6597, France .
    Towards standardized 3DTV QoE assessment: Cross-lab study on display technology and viewing environment parameters2013In: Proceedings of SPIE - The International Society for Optical Engineering, 2013, p. Art. no. 864809-Conference paper (Refereed)
    Abstract [en]

    Subjective assessment of Quality of Experience in stereoscopic 3D requires new guidelines for the environmental setup as existing standards such as ITU-R BT. 500 may no longer be appropriate. A first step is to perform cross-lab experiments in different viewing conditions on the same video sequences. Three international labs performed Absolute Category Rating studies on a freely available video database containing degradations that are mainly related to video quality degradations. Different conditions have been used in the labs: Passive polarized displays, active shutter displays, differences in viewing distance, the number of parallel viewers, and the voting device. Implicit variations were introduced due to the three different languages in Sweden, South Korea, and France. Although the obtained Mean Opinion Scores are comparable, slight differences occur in function of the video degradations and the viewing distance. An analysis on the statistical differences obtained between the MOS of the video sequences revealed that obtaining an equivalent number of differences may require more observers in some viewing conditions. It was also seen that the alignment of the meaning of the attributes used in Absolute Category Rating in different languages may be beneficial. Statistical analysis was performed showing influence of the viewing distance on votes and MOS results.

  • 11.
    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.

  • 12.
    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.

  • 13.
    Bergman, Jens
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Wallin, Fredrik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    3D-portal: Kommunikation i 3D2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In todays society internet is used for communication between each other aroundthe world. The first video call was made around the year 1940 and it is time fora development, where 3D is something that can make video calls more real. Tomake this possible a system was constructed that would be able to get data fromdifferent time-of-flight cameras and color cameras and audio devices. That datashould later on be compressed and transmitted over internet to be able to play iton someone else’s 3D-display. To prevent the feeling of delay in the call, allparts together must happen in real time. The development methods that havebeen used is pair programming and a variation of test-driven development. Thesystem has been evaluated by time messurements, image quality and data sizeto find a good balance between time and quality. The system was constructedby five parts: capturing of images and audio, image upscaling, compression anddecompression, network streaming and also rendering. The result showed thatthe parts affected by data size and image quality could achieve a good balancebetween time and quality. However, all goals could not be achieved becausesome parts where too slow for the real time goal to be achieved and also someparts could not be constructed in time. Since the system was built up modularlythe parts that did not achieve the goals can be improved or replaced. Based onthe results, solution proposals was made to improve the results for a possiblefurther development.

  • 14. Bosk, Daniel
    et al.
    Kjellqvist, Martin
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Buchegger, Sonja
    Towards Perfectly Secure and Deniable Communication Using an NFC-Based Key-Exchange Scheme2015In: SECURE IT SYSTEMS, NORDSEC 2015, 2015, Vol. 9417, p. 72-87Conference paper (Refereed)
    Abstract [en]

    In this paper we first analyse the possibility for deniability under a strong adversary, who has an Internet-wide transcript of the communication. Secondly, we present a scheme which provides the desirable properties of previous messaging schemes, but with stronger deniability under the new adversary model. Our scheme requires physical meetings for exchanges of large amounts of random key-material via near-field communication and later uses this random data to key a one-time pad for text-messaging. We prove the correctness of the protocol and, finally, we evaluate the practical feasibility of the suggested scheme.

  • 15.
    Bosse, Sebastian
    et al.
    Fraunhofer Institute for Telecommunications – Heinrich Hertz Institute, Berlin, Germany.
    Brunnström, Kjell
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology. Research Intstitutes of Sweden AB.
    Arndt, Sebastian
    Norwegian University of Science and Technology, Trondheim, Norway.
    Martini, Maria G.
    Kingston University, London, UK.
    Ramzan, Naeem
    University of the West of Scotland, Hamilton, UK.
    Engelke, Ulrich
    CSIRO Data61, Kensington, Australia.
    A common framework for the evaluation of psychophysiological visual quality assessment2019In: Quality and User Experience, ISSN 2366-0139, E-ISSN 2366-0147, Vol. 4, no 3Article in journal (Refereed)
    Abstract [en]

    The assessment of perceived quality based on psychophysiological methods recently gained attraction as it potentially overcomes certain flaws of psychophysical approaches. Although studies report promising results, it is not possible to arrive at decisive and comparable conclusions that recommend the use of one or another method for a specific application or research question. The video quality expert group started a project on psychophysiological quality assessment to study these novel approaches and to develop a test plan that enables more systematic research. This test plan comprises of a specifically designed set of quality annotated video sequences, suggestions for psychophysiological methods to be studied in quality assessment, and recommendations for the documentation and publications of test results. The test plan is presented in this article.

  • 16.
    Brunnström, Kjell
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems. Dept. of NetLab, Visual Media Quality, Acreo Swedish ICT AB, Sweden .
    Wang, Kun
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science. Dept. of NetLab, Visual Media Quality, Acreo Swedish ICT AB, Sweden .
    Andrén, B.
    Dept. of NetLab, Visual Media Quality, Acreo Swedish ICT AB, Sweden .
    Simulator Sickness analysis of 3D video viewing on passive 3D TV2013In: Proceedings of SPIE - The International Society for Optical Engineering, 2013, p. Art. no. 864802-Conference paper (Refereed)
    Abstract [en]

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

  • 17.
    Burgos, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Mittuniversitetets Android-app: Studentportalen som mobilapplikation2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project is made for creating a stabil and useful mobile application developed in Java. The purpose of this project is to make the access and communication easier between the student and the student portal. The product of this project is the unofficial app of Mid Sweden University, called Mittuniversitetets Android-app, that in first hand is limited to Android-devices. By doing research, both by letting students answer a survey online on Mid Sweden University's student portal and by asking student physically at Mid Sweden University campus Sundsvall, the investigation tells which parts of the student portal students would like to have in the mobile application and it is according to those answers that the direction of the application has been developed. The product, which is the application, is considered complete when the students are able to for exempel reach their information and get the information presented in a good way. Three different suggestions for a solution is given and by comparing the benefits of those only one solution is chosen. The solution chosen is ”direct-connection as solution”. To be able to give the reader better basical and understandable knowledge some parts are explained in more detail in this report. The report also shows that the access to the student portal is more effective now that only 5 taps are required by using the Mid Sweden University application to get a students information instead of 24 taps by using the web-browser on the cellphone. All goals in this thesis is considered accomplished and screenshots shows this in the report. Finally there is also suggestions for some future works given in this report.

  • 18.
    Butun, Ismail
    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.
    Detecting Intrusions in Cyber-Physical Systems of Smart Cities: Challenges and Directions2019In: Secure Cyber-Physical Systems for Smart Cities / [ed] Riaz Ahmed Shaikh, Hershey, USA: IGI Global, 2019, p. 74-102Chapter in book (Refereed)
    Abstract [en]

    Interfacing the smart cities with cyber-physical systems (CPSs) improves cyber infrastructures while introducing security vulnerabilities that may lead to severe problems such as system failure, privacy violation, and/or issues related to data integrity if security and privacy are not addressed properly. In order for the CPSs of smart cities to be designed with proactive intelligence against such vulnerabilities, anomaly detection approaches need to be employed. This chapter will provide a brief overview of the security vulnerabilities in CPSs of smart cities. Following a thorough discussion on the applicability of conventional anomaly detection schemes in CPSs of smart cities, possible adoption of distributed anomaly detection systems by CPSs of smart cities will be discussed along with a comprehensive survey of the state of the art. The chapter will discuss challenges in tailoring appropriate anomaly detection schemes for CPSs of smart cities and provide insights into future directions for the researchers working in this field.

  • 19.
    Chen, Hao
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Priority-based THVRG in Industrial Wireless Sensor Network2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With the constant expansion of the industrial monitoring system, there is an urgent requirement to reduce investment and operating costs for the development of industrial communication technology. For industrial real-time monitoring systems, wireless technology can be used in a practical industrial production to take advantages of its flexibility and robustness. As wireless sensor networks have many advantages such as low investment costs, flexible structure and ease of transformation, it has become the focus with regards to industrial areas. THVRG is a routing algorithm that selects the routing path based on two-hop information. Since different information sensed by the sensors may have different requirements in order to reach the sink, a priority-based routing algorithm is required in order to adapt to this kind of situation. This thesis has proposed a priority routing algorithm based on the THVRG (Priority-based THVRG). In addition, a simulation of this algorithm was performed in OPNET. Finally, the report provides an evaluation of the proposed algorithm in industrial wireless sensor networks.

  • 20.
    Chen, Jian
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Maintaining Stream Data Distribution Over Sliding Window2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In modern applications, it is a big challenge that analyzing the order statistics about the most recent parts of the high-volume and high velocity stream data. There are some online quantile algorithms that can

    keep the sketch of the data in the sliding window and they can answer the quantile or rank query in a very short time. But most of them take the

    GK algorithm as the subroutine, which is not known to be mergeable. In this paper, we propose another algorithm to keep the sketch that maintains the order statistics over sliding windows. For the fixed-size window, the existing algorithms can’t maintain the correctness in the process of updating the sliding window. Our algorithm not only can maintain the correctness but also can achieve similar performance of the optimal algorithm. Under the basis of maintaining the correctness, the insert time and query time are close to the best results, while others can't maintain the correctness. In addition to the fixed-size window algorithm, we also provide the time-based window algorithm that the window size varies over time. Last but not least, we provide the window aggregation algorithm which can help extend our algorithm into the distributed system.

  • 21.
    Dadash Pour Khalkhali, Mohammad Mehdi
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    User Experience Enhancement in 3D Video Conferencing2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

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

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

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

  • 22.
    Danielson, Mats
    et al.
    Dept. of Computer and Systems Sciences, Stockholm University.
    Ekenberg, Love
    Dept. of Computer and Systems Sciences, Stockholm University.
    Larsson, Aron
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Generalised Risk Constraints in Decision Trees with Second-Order Probabilities2012In: Advances in Economics, Risk Management, Political and Law Science / [ed] D. Pavelkova, J. Strouhal, M. Pasekova, WSEAS Press , 2012, p. 376-383Conference paper (Refereed)
    Abstract [en]

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

  • 23.
    Danielson, Mats
    et al.
    Dept. of Computer and Systems Sciences, Stockholm University.
    Ekenberg, Love
    Dept. of Computer and Systems Sciences, Stockholm University.
    Larsson, Aron
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Riabacke, Mona
    Dept. of Computer and Systems Sciences, Stockholm University.
    Weighting Under Ambiguous Preferences and Imprecise Differences in a Cardinal Rank Ordering Process2013In: International Journal of Computational Intelligence Systems, ISSN 1875-6883, Vol. 7, no 1, p. 105-112Article in journal (Refereed)
    Abstract [en]

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

  • 24.
    Dhali, Salle
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Web application development with .NET: 3-tier architecture2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The reason for performing this project work is to develop a Web application for the Student Union of Mid Sweden University applying the modern and comprehensive Microsoft .NET framework platform architecture. At present, the existing web application is divided into several modules which are built of server‐side scripting language technique and an open source database. The customer would like to develop the entire web applications using the Microsoft development tools and technologies in order to determine the possible benefit which could be obtained in terms of cost, maintenance, flexibility and the security perspective issues and also in terms of user friendly interactions options for all the involving partners in an effective way. The primary aim for the project is to start building a bookstore module for the Students Union that is responsible for selling literature to the students at the University. The module will also be integrated into a database system into which an administrator, a member of staff working in the Student Union, will be able to add a new book when it arrives and also update or delete if necessary later on. In addition to this module application all the book’s details belong to a certain category viewable to the students. The other part of this project work is aiming at finding a pattern similar to the bookstore module in which ordinary users can authenticate them towards a database and be able to add their curriculum vitae data entry and update it at a later stage as required.

  • 25.
    Dima, Elijs
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Development of interactive entertainment system for Din Tur buses: Håll Platsen2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

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

  • 26.
    Dobslaw, Felix
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science.
    End-to-End Quality of Service Guarantees for Wireless Sensor Networks2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Wireless sensor networks have been a key driver of innovation and societal progressover the last three decades. They allow for simplicity because they eliminate ca-bling complexity while increasing the flexibility of extending or adjusting networksto changing demands. Wireless sensor networks are a powerful means of fillingthe technological gap for ever-larger industrial sites of growing interconnection andbroader integration. Nonetheless, the management of wireless networks is difficultin situations wherein communication requires application-specific, network-widequality of service guarantees. A minimum end-to-end reliability for packet arrivalclose to 100% in combination with latency bounds in the millisecond range must befulfilled in many mission-critical applications.The problem addressed in this thesis is the demand for algorithmic support forend-to-end quality of service guarantees in mission-critical wireless sensor networks.Wireless sensors have traditionally been used to collect non-critical periodic read-ings; however, the intriguing advantages of wireless technologies in terms of theirflexibility and cost effectiveness justify the exploration of their potential for controland mission-critical applications, subject to the requirements of ultra-reliable com-munication, in harsh and dynamically changing environments such as manufactur-ing factories, oil rigs, and power plants.This thesis provides three main contributions in the scope of wireless sensor net-works. First, it presents a scalable algorithm that guarantees end-to-end reliabilitythrough scheduling. Second, it presents a cross-layer optimization/configurationframework that can be customized to meet multiple end-to-end quality of servicecriteria simultaneously. Third, it proposes an extension of the framework used toenable service differentiation and priority handling. Adaptive, scalable, and fast al-gorithms are proposed. The cross-layer framework is based on a genetic algorithmthat assesses the quality of service of the network as a whole and integrates the phys-ical layer, medium access control layer, network layer, and transport layer.Algorithm performance and scalability are verified through numerous simula-tions on hundreds of convergecast topologies by comparing the proposed algorithmswith other recently proposed algorithms for ensuring reliable packet delivery. Theresults show that the proposed SchedEx scheduling algorithm is both significantlymore scalable and better performing than are the competing slot-based schedulingalgorithms. The integrated solving of routing and scheduling using a genetic al-vvigorithm further improves on the original results by more than 30% in terms of la-tency. The proposed framework provides live graphical feedback about potentialbottlenecks and may be used for analysis and debugging as well as the planning ofgreen-field networks.SchedEx is found to be an adaptive, scalable, and fast algorithm that is capa-ble of ensuring the end-to-end reliability of packet arrival throughout the network.SchedEx-GA successfully identifies network configurations, thus integrating the rout-ing and scheduling decisions for networks with diverse traffic priority levels. Fur-ther, directions for future research are presented, including the extension of simula-tions to experimental work and the consideration of alternative network topologies.

  • 27.
    Dobslaw, Felix
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    InPUT: The Intelligent Parameter Utilization Tool2012In: GECCO Companion 12: Proceedings of the fourteenth international conference on Genetic and evolutionary computation conference companion, New York, NY, USA: ACM Press, 2012, p. 149-156Conference paper (Refereed)
    Abstract [en]

    Computer experiments are part of the daily business formany researchers within the area of computational intelligence. However, there is no standard for either human orcomputer readable documentation of computer experiments.Such a standard could considerably improve the collaboration between experimental researchers, given it is intuitiveto use. In response to this deficiency the Intelligent Param-eter Utilization Tool ( InPUT ) is introduced. InPUT offers ageneral and programming language independent format forthe definition of parameters and their ranges. It providesservices to simplify the implementation of algorithms andcan be used as a substitute for input mechanisms of existing frameworks. InPUT reduces code-complexity and increases the reusability of algorithm designs as well as the reproducibility of experiments. InPUT is available as open-source for Java and this will soon also be extended to C++, two ofthe predominant languages of choice for the development ofevolutionary algorithms.

  • 28.
    Dobslaw, Felix
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Zhang, Tinting
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Challenges for the use of data aggregation in industrial Wireless Sensor Networks2015In: IEEE International Conference on Automation Science and Engineering, IEEE Computer Society, 2015, p. 138-144Conference paper (Refereed)
    Abstract [en]

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

  • 29.
    Dobslaw, Felix
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science.
    Tingting, Zhang
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Latency Improvement Strategies for Reliability-Aware Scheduling in Industrial Wireless Sensor Networks2015In: International Journal of Distributed Sensor Networks, ISSN 1550-1329, E-ISSN 1550-1477, article id 178368Article in journal (Refereed)
    Abstract [en]

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

  • 30.
    Dobslaw, Felix
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science.
    Zhang, Tingting
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    A Reliability-Aware Cross-layer Optimization Framework for Wireless Sensor Networks.Manuscript (preprint) (Other academic)
    Abstract [en]

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

  • 31.
    Dobslaw, Felix
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science.
    Zhang, Tingting
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    End-to-End Reliability-aware Scheduling for Wireless Sensor Networks2016In: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050, Vol. 12, no 2, p. 758-767Article in journal (Refereed)
    Abstract [en]

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

  • 32.
    Dobslaw, Felix
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Computer and System science.
    Zhang, Tingting
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    QoS Assessment for Mission-critical Wireless Sensor Network Applications2013In: Proceedings - Conference on Local Computer Networks, LCN / [ed] Matthias Wählisch, IEEE Xplore , 2013, p. 663-666Conference paper (Refereed)
    Abstract [en]

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

  • 33.
    Eggestig, Lars
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Wodajo, Mintesinot
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Integration of BankID Services in a PhoneGap Based Mobile Application2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

  • 34.
    Ekenberg, Love
    et al.
    Dept. of Computer and Systems Sciences, Stockholm University.
    Danielson, Mats
    Dept. of Computer and Systems Sciences, Stockholm University.
    Larsson, Aron
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Sundgren, David
    Dept. of Computer and Systems Sciences, Stockholm University.
    Second-Order Risk Constraints in Decision Analysis2014In: Axioms, ISSN 2075-1680, Vol. 3, no 1, p. 31-45Article in journal (Refereed)
    Abstract [en]

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

  • 35.
    Ekström, Marcus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Communication tool in virtual reality – A telepresence alternative: An alternative to telepresence – bringing the shared space to a virtual environment in virtual reality2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Videoconferencing is one of the most common telepresence methods today and educational videos is rising in popularity among distance learners. Traditional videoconferencing is unable to convey gestures and mutual eye contact between participants. This study aim to propose a Virtual Reality telepresence solution using game engines. A literature study confirmed the effectiveness achieved in VR is comparable to the effectiveness in face-to-face meetings. The suggested solution implements whiteboard functionality from a real-life perspective, confirming it is possible to include new functionality and directly transfer old functionality to the VR system from the communication systems today. The system was evaluated based on the response time, packet loss, bandwidth, frame rate and through user tests. The evaluation shows it is possible to design a telepresence system with VR capable of passing the Turing Test for Telepresence. The participants of the user tests did not experience discomfort and they were positively inclined to the telepresence system. Though, discomfort may emerge if the VR character is used with a common office workstation. Future studies in this topic would involve modifications of the third person camera, making the head's rotation follow the direction of the camera view and implementing movable eye pupils on the VR character using the upcoming eye-tracking accessory.

  • 36.
    Fasth, Tobias
    et al.
    Dept. of Computer and Systems Sciences, Stockholm University, Sweden.
    Larsson, Aron
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Sensitivity Analysis in Portfolio Interval Decision Analysis2013In: FLAIRS 2013 - Proceedings of the 26th International Florida Artificial Intelligence Research Society Conference, 2013, p. 609-614Conference paper (Refereed)
    Abstract [en]

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

  • 37.
    Fedorov, Igor
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Lawal, Najeem
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    O'Nils, Mattias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Alqaysi, Hiba
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Placement Strategy of Multi-Camera Volumetric Surveillance System for Activities Monitoring2017In: ICDSC 2017 Proceedings of the 11th International Conference on Distributed Smart Cameras, New York, NY, USA: Association for Computing Machinery (ACM), 2017, Vol. F132201, p. 113-118Conference paper (Refereed)
    Abstract [en]

    The design of multi-camera surveillance system comes with many advantages, for example it facilitates as understanding how flying objects act in a given volume. One possible application is for the observation interaction of birds and calculate their trajectories around wind turbines to create promising systems for preventing bird collisions with turbine blades. However, there are also challenges, such as finding the optimal node placement and camera calibration. To address these challenges we investigated a trade-off between calibration accuracy and node requirements, including resolution, modulation transfer function, field of view and angle baseline. We developed a strategy for camera placement to achieve improved coverage for golden eagle monitoring and tracking. This strategy based on the modified resolution criterion taking into account the contrast function of the camera and the estimation of the base angle between the cameras.

  • 38.
    Feng, Yuan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Improve Data Quality By Using Dependencies And Regular Expressions2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The objective of this study has been to answer the question of finding ways to improve the quality of database. There exists a lot of problems of the data stored in the database, like missing or spelling errors. To deal with the dirty data in the database, this study adopts the conditional functional dependencies and regular expressions to detect and correct data. Based on the former studies of data cleaning methods, this study considers the more complex conditions of database and combines the efficient algorithms to deal with the data. The study shows that by using these methods, the database’s quality can be improved and considering the complexity of time and space, there still has a lot of things to do to make the data cleaning process more efficiency.

  • 39.
    Flodin, Anton
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Leerec: A scalable product recommendation engine suitable for transaction data.2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    We are currently living in the Internet of Things (IoT) era, which involves devices that are connected to Internet and are communicating with each other. Each year, the number of devices increases rapidly, which result in rapid growth of data that is generated. This large amount of data is sometimes titled as Big Data, which is generated from different sources, such as log data of user behavior. These log files can be collected and analyzed in different ways, such as creating product recommendations. Product recommendations have been around since the late 90s, when the amount of data collected were not at the same level as it is today. The aim of this thesis has been to investigating methods to process and create product recommendations to see how well they are adapted for Big Data. This has been accomplished by three theory studies on how to process user events, how to make the product recommendation algorithm called collaborative filtering scalable and finally how to convert implicit feedback to explicit feedback (ratings).

    This resulted in a recommendation engine consisting of Apache Spark as the data processing system, which had three functions: read multiple log files and concatenate log files for each month, parsing the log files of the user events to create explicit ratings from the transactions and create four types of recommendations. The NoSQL database MongoDB was chosen as the database to store the different types of product recommendations that was created. To be able to get the recommendations from the recommendation engine and the database, a REST API was implemented which can be used by any third-party. What can be concluded from the results of this thesis work is that the system that was implemented is partial scalable. This means that Apache Spark was scalable for both concatenating files, parse and create ratings and also create the recommendations using the ALS method. However, MongoDB was shown to be not scalable when managing more than 100 concurrent requests. Future work involves making the recommendation engine distributed in a multi-node cluster to utilize the parallelization of Apache Spark. Other recommendations include considering other NoSQL databases that might be more scalable than MongoDB.

  • 40.
    Forsström, Stefan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Enabling fully distributed global services on the Internet-of Things2014Doctoral thesis, comprehensive summary (Other academic)
  • 41.
    Forsström, Stefan
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Kanter, Theo
    Department of Computer and System Sciences, Stockholm University, Kista, SE-164 40, Sweden .
    Continuously Changing Information on a Global Scale and its Impact for the Internet-of-Things2014In: Journal on spesial topics in mobile networks and applications, ISSN 1383-469X, E-ISSN 1572-8153, Vol. 19, no 1, p. 33-44Article in journal (Refereed)
    Abstract [en]

    This article analyzes the challenges of supportingcontinual changes of context information in Internetof-Things applications. These applications require aconstant flow of continuously changing information fromsensor based sources in order to ensure a high quality-ofexperience.However, an uncontrolled flow between sourcesand sinks on a global scale wastes resources, such ascomputational power, communication bandwidth, andbattery time. In response to these challenges we presenta general approach which focuses on four layers wherewe provide a proposed solution to each layer. We haverealized the general model into a proof-of-concept implementationrunning on devices with limited resources,where we can moderate the information exchange basedon relevance and sought after quality-of-experience bythe applications. In conclusion, we evaluate our solutionand present a summary of our experiences regardingthe impact of continuously changing information on theInternet-of-Things.

  • 42.
    Forsström, Stefan
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Kanter, Theo
    Department of Computer and System Sciences, Stockholm University, Kista, 164 40, Sweden .
    Enabling Ubiquitous Sensor-Assisted Applications on the Internet-of-Things2014In: Personal and Ubiquitous Computing, ISSN 1617-4909, E-ISSN 1617-4917, Vol. 18, no 4, p. 977-986Article in journal (Refereed)
    Abstract [en]

    The increase in sensor-assisted applicationssuch as sensing campaigns and interactions in large-scalepopulations put new demands on seamless sharing ofsensor information on a global scale. Existing support islimited due to simplified information models reflectingnarrow application scenarios and poorly scaling architectures.In response to this, we present an application architecturefor pervasive internet-of-things applications whichcircumvents these limitations. Our architecture enablesapplications to utilize information from sensors and wirelesssensor networks via a peer-to-peer overlay. Theoverlay shares sensor information in an generic informationmodel, which is extensible and thus enables intelligentapplication behavior. Our evaluation of the architectureindicates that it supports the sharing of sensor informationon a global scale in sensor-assisted applications, with lowresponse times. Finally, we evaluate the feasibility ofrunning such applications in end devices with limitedresources in a sensor-assisted application prototype.

  • 43.
    Forsström, Stefan
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Kanter, Theo
    Department of Computer and System Sciences Stockholm University.
    Johansson, Olle
    Acreo AB, SE-824 42 Hudiksvall, Sweden.
    Real-Time Distributed Sensor-Assisted mHealth Applications on the Internet-of-Things2012In: Proc. of the 11th IEEE Int. Conference on Trust, Security and Privacy in Computing and Communications, TrustCom-2012: 11th IEEE Int. Conference on Ubiquitous Computing and Communications, IUCC-2012, IEEE conference proceedings, 2012, p. 1844-1849Conference paper (Refereed)
    Abstract [en]

    Existing sensor-assisted mHealth applications wouldbenefit from large-scale sharing of sensor information in realtime.Existing communication solutions are however limited inthis respect, because of centralized application-level communication.In response to this, we presents a distributed communicationsolution for mHealth applications which circumvents these limitations.Our Internet-of-Things architecture enables mHealth applicationsto utilize information from sensors and wireless sensornetworks via a peer-to-peer overlay, where sensor information isorganized in an information model which is stored in the overlayitself. We present a proof-of-concept application and evaluationresults regarding the architecture’s real-time capabilities. Theresults indicate that a fully distributed architecture can supportreal-time sensing in mHealth applications and the support isavailable as an open source platform, MediaSense. Current workis focused on evaluating scalability in very large scale scenariosusing field trials.

  • 44.
    Forsström, Stefan
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Kanter, Theo
    Department of Computer and System Sciences Stockholm University.
    Österberg, Patrik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Ubiquitous Secure Interactions with Intelligent Artifacts on the Internet-of-Things2012In: Proc. of the 11th IEEE Int. Conference on Trust, Security and Privacy in Computing and Communications, TrustCom-2012: 11th IEEE Int. Conference on Ubiquitous Computing and Communications, IUCC-2012, IEEE conference proceedings, 2012, p. 1520-1524Conference paper (Refereed)
    Abstract [en]

    Intelligent artifacts are real-world objects enhancedwith capabilities in order to display relevant behavior in varioustypes of context-aware applications, such as in mHealth,commerce, or pervasive games. This can be achieved by attachingsensors and store associated information on the Internet.Interaction with such artifacts requires secure communication,to protect personal and private information. This mandatesresearch in how to safeguard interactions via heterogeneousmeans of communication involving interconnected local and nonlocalartifacts. In response to these challenges, this paper presentskey schemes to secure interaction via heterogeneous means ofcommunication. In conclusion, the architecture can securelyauthenticate an intelligent artifact as well as securely exchangesensor information with other authenticated artifacts attached inan overlay. Our proof-of-concept application demonstrated in anInternet-of-Things platform validates the approach.

  • 45.
    Forsström, Stefan
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Kardeby, Victor
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Estimating Contextual Situations using Indicators from Smartphone Sensor Values2014In: Proceedings - 2014 IEEE International Conference on Internet of Things, iThings 2014, 2014 IEEE International Conference on Green Computing and Communications, GreenCom 2014 and 2014 IEEE International Conference on Cyber-Physical-Social Computing, CPS 2014, 2014, p. 243-250, article id 7059668Conference paper (Refereed)
    Abstract [en]

    Current context-aware applications often use thelocation of a user as the only indication of the current situation.These existing applications are therefore limited in their situationawareness, because of the poor indoor resolution of the locationsensor and its high resource consumption. In response to theselimitations we present an approach to estimate the contextualsituation of a user without using resource inefficient locationsensors. Our proposed solution utilizes a wide range of lowpowered sensors, together with two modified machine learningtechniques to estimate the situation in a more resource efficientmanner. Simulations and a proof-of-concept application show thatthe situation of a user can be determined within 50 ms at anaccuracy above 90%, when only using the low energy sensorsavailable on a smartphone and its limited processing power.

  • 46.
    Forsström, Stefan
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Kardeby, Victor
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Österberg, Patrik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Jennehag, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Challenges when Realizing a Fully Distributed Internet-of-Things - How we Created the SensibleThings Platform2014In: ICDT 2014, The Ninth International Conference on Digital Telecommunications / [ed] Constantin Paleologu, University Politehnica of Bucharest, Romania Andy Snow, Ohio University, USA, 2014, p. 13-18Conference paper (Refereed)
    Abstract [en]

    The SensibleThings platform is an open source architecturefor enabling Internet-of-Things based applications.During its development, multiple problems have been faced andsolved, for example issues related to networking, information dissemination,sensors, and application access. This paper describesthese problems and the technical solutions that are implementedin the platform. We also present the current progress and aseries of demonstrator applications, which show the wide rangeof possibilities enabled by the platform. Finally, we present futurework and how it will be used in future research endeavors andcommercial interests.

  • 47.
    Försth, Sebastian
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    When your finger isn't enough: New ways to increase the accessibility of mobile phones2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The objective of this study has been to answer three questions. The questions are Can you navigate in a different way than with your fingers, Do you lose any functionality in the application when you are not using your fingers and is the solution a reasonable way to navigate. The study consist of two parts, the first is to create a navigation library with different navigation methods and the second part is to evaluate the navigation methods using user tests. The study shows that it is possible to navigate without the use of fingers and address problems and solution to navigate without the use of fingers. The study shows how different navigation methods perform compared to each other and compared to navigating with the use of fingers.

  • 48.
    Gebre, Tamrat Gebremedhin
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Automatic recognition of tree trunks in images: Robotics in forest industry2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 49.
    Ghanta, Sairam
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    A STEP Implementation for Product Data Exchange: DT005A2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    SCANIA does the automobile production based on Modular Approach. A ModularSystem provides a huge variety of specifications to meet varying dramatic needs fordifferent customers. Modular approach with the support of reusable components increasesthe efficiency of designing different products.The main stream product design is performed on CATIA V5 platform with ENOVIAas its PDM vault. But SCANIA uses its own legacy PDM SPECTRA for maintainingthe product structure for modular based product specification.So to design the 3D parts in CATIA, one should import the product structure fromSPECTRA to ENOVIA. But this process includes a conversion from SPECTRA formatto ENOVIA format and currently it is performed using a third party componentnamed ECCO. Now, SCANIA wants to replace ECCO for various reasons with inhousebuild module.This report discusses the background knowledge of the problem, methodology usedin the solution approach, different implementations along with their results and finallyconcluding with future work of solutions.

    Keywords: CATIA,ENOVIA,CAA,JSDAI,ECCO,EXPRESS,EXPRESS-X

  • 50.
    Guan, Xiao
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Deterministic and Flexible Parallel Latent Feature Models Learning Framework for Probabilistic Knowledge Graph2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Knowledge Graph is a rising topic in the field of Artificial Intelligence. As the current trend of knowledge representation, Knowledge graph research is utilizing the large knowledge base freely available on the internet.

    Knowledge graph also allows inspection, analysis, the reasoning of all knowledge in reality. To enable the ambitious idea of modeling the knowledge of the world, different theory and implementation emerges. Nowadays, we have the opportunity to use freely available information from Wikipedia and Wikidata. The thesis investigates and formulates a theory about learning from Knowledge Graph. The thesis researches probabilistic knowledge graph. It only focuses on a branch called latent feature models in learning probabilistic knowledge graph. These models aim to predict possible relationships of connected entities and relations. There are many models for such a task. The metrics and training process is detailed described and improved in the thesis work. The efficiency and correctness enable us to build a more complex model with confidence. The thesis also covers possible problems in finding and proposes future work.

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