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  • 201.
    Lavassani, Mehrzad
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Reliable Information Exchange in IIoT: Investigation into the Role of Data and Data-Driven Modelling2018Licentiate thesis, monograph (Other academic)
    Abstract [en]

    The concept of Industrial Internet of Things (IIoT) is the tangible building block for the realisation of the fourth industrial revolution. It should improve productivity, efficiency and reliability of industrial automation systems, leading to revenue growth in industrial scenarios. IIoT needs to encompass various disciplines and technologies to constitute an operable and harmonious system. One essential requirement for a system to exhibit such behaviour is reliable exchange of information. In industrial automation, the information life-cycle starts at the field level, with data collected by sensors, and ends at the enterprise level, where that data is processed into knowledge for business decision making. In IIoT, the process of knowledge discovery is expected to start in the lower layers of the automation hierarchy, and to cover the data exchange between the connected smart objects to perform collaborative tasks.

    This thesis aims to assist the comprehension of the processes for information exchange in IIoT-enabled industrial automation- in particular, how reliable exchange of information can be performed by communication systems at field level given an underlying wireless sensor technology, and how data analytics can complement the processes of various levels of the automation hierarchy. Furthermore, this work explores how an IIoT monitoring system can be designed and developed.

    The communication reliability is addressed by proposing a redundancy-based medium access control protocol for mission-critical applications, and analysing its performance regarding real-time and deterministic delivery. The importance of the data and the benefits of data analytics for various levels of the automation hierarchy are examined by suggesting data-driven methods for visualisation, centralised system modelling and distributed data streams modelling. The design and development of an IIoT monitoring system are addressed by proposing a novel three-layer framework that incorporates wireless sensor, fog, and cloud technologies. Moreover, an IIoT testbed system is developed to realise the proposed framework.

    The outcome of this study suggests that redundancy-based mechanisms improve communication reliability. However, they can also introduce drawbacks, such as poor link utilisation and limited scalability, in the context of IIoT. Data-driven methods result in enhanced readability of visualisation, and reduced necessity of the ground truth in system modelling. The results illustrate that distributed modelling can lower the negative effect of the redundancy-based mechanisms on link utilisation, by reducing the up-link traffic. Mathematical analysis reveals that introducing fog layer in the IIoT framework removes the single point of failure and enhances scalability, while meeting the latency requirements of the monitoring application. Finally, the experiment results show that the IIoT testbed works adequately and can serve for the future development and deployment of IIoT applications.

  • 202.
    Lavassani, Mehrzad
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Forsström, Stefan
    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.
    Zhang, Tingting
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Combining Fog Computing with Sensor Mote Machine Learning for Industrial IoT2018In: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 18, no 5, article id 1532Article in journal (Refereed)
    Abstract [en]

    Digitalization is a global trend becoming ever more important to our connected and sustainable society. This trend also affects industry where the Industrial Internet of Things is an important part, and there is a need to conserve spectrum as well as energy when communicating data to a fog or cloud back-end system. In this paper we investigate the benefits of fog computing by proposing a novel distributed learning model on the sensor device and simulating the data stream in the fog, instead of transmitting all raw sensor values to the cloud back-end. To save energy and to communicate as few packets as possible, the updated parameters of the learned model at the sensor device are communicated in longer time intervals to a fog computing system. The proposed framework is implemented and tested in a real world testbed in order to make quantitative measurements and evaluate the system. Our results show that the proposed model can achieve a 98% decrease in the number of packets sent over the wireless link, and the fog node can still simulate the data stream with an acceptable accuracy of 97%. We also observe an end-to-end delay of 180 ms in our proposed three-layer framework. Hence, the framework shows that a combination of fog and cloud computing with a distributed data modeling at the sensor device for wireless sensor networks can be beneficial for Industrial Internet of Things applications.

  • 203.
    Lawler Karvonen, Timothy
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Native versus non native: A comparison of React Native and Angular NativeScript to native mobile applicationsParallelism in Node.js applications2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The traditional or the native way to develop mobile applications is to use Java for Android and Objective-c or Swift for iOS. The native way is favored by many since the code and the functionality is optimized for the platform. An- other way to develop mobile applications is to do it the non-native way, with a programming language or technique not made for the platform. This approach has for long been frowned upon due the limited hardware access and perfor- mance loss. React Native and NativeScript offers mobile application develop- ment in a non-native way said full access to the native platforms API using JavaScript all from a single code base. The aim of this thesis has been to de- velop and compare four proof of concept applications of which two are devel- oped natively for Android and iOS and the other are developed using the non- native React Native and NativeScript. The comparison is based on three as- pects: accessing the device’s native hardware and APIs based on what the com- pany Dewire requires from mobile applications, the performance difference on the respective platform and code reusability cross platform. There is no big dif- ference between React Native and NativeScript when comparing native access and everything that was accessible on the native implementation was accessible on the non-native implementation. Based on the performance measurements, React Native falls behind NativeScript. NativeScript handles long lists better than React Native. Lastly a discussion is presented regarding code reusability when developing non-native applications along with some experienced best practices when doing so.

  • 204.
    L'ecuer, Pierre
    et al.
    University of Montreal, Montréal, Canada.
    Gustavsson, Klas
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Olsson, Leif
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Modeling Bursts In The Arrival Process To An Emergency Call Center2018In: Proceedings of the 2018 Winter Simulation Conference / [ed] M. Rabe, A. A. Juan, N. Mustafee, A. Skoogh, S. Jain, and B. Johansson, eds, IEEE, 2018, p. 525-- 536, article id 8632536Conference paper (Refereed)
    Abstract [en]

    In emergency call centers (for police, firemen, ambulances) a single event can sometimes trigger many incoming calls in a short period of time. Several people may call to report the same fire or the same accident, for example. Such a sudden burst of incoming traffic can have a significant impact on the responsiveness of the call center for other events in the same period of time. We examine data from the SOS Alarm center in Sweden. We also build a stochastic model for the bursts. We show how to estimate the model parameters for each burst by maximum likelihood, how to model the multivariate distribution of those parameters using copulas, and how to simulate the burst process from this model. In our model, certain events trigger an arrival process of calls with a random time-varying rate over a finite period of time of random length.

  • 205.
    Lennvall, Tomas
    et al.
    RISE SICS, Västerås.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Åkerberg, Johan
    ABB Corporate Research, Sweden.
    Challenges when bringing IoT into Industrial Automation2017In: AFRICON, 2017 IEEE / [ed] Darryn R. Cornish, IEEE, 2017, p. 905-910, article id 8095602Conference paper (Refereed)
    Abstract [en]

    The Internet of Things (IoT) is captivating the society because of its potential to rapidly transform businesses and people’s lives. It is widely believed that IoT will also transform the industrial automation business in terms of improved productivity, less cost, flexibility, and increased revenues. Hence, there are some challenges that needs to be addressed when IoT is introduced to the industrial automation domain. This paperaims to present realistic requirements and highlights identified challenges such as security, interoperability, deterministic and low latency communication, and how the required availability (uptime) can be kept. Moreover, the paper also point out the need of standardization and sustainable business models. The conclusion is that introducing IoT devices and connecting them directly to cloud services is not straightforward for process automation.

  • 206.
    Li, Chuhe
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    A sliding window BIRCH algorithm with performance evaluations2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    An increasing number of applications covered various fields generate transactional data or other time-stamped data which all belongs to time series data. Time series data mining is a popular topic in the data mining field, it introduces some challenges to improve accuracy and efficiency of algorithms for time series data. Time series data are dynamical, large-scale and high complexity, which makes it difficult to discover patterns among time series data with common methods suitable for static data. One of hierarchical-based clustering methods called BIRCH was proposed and employed for addressing the problems of large datasets. It minimizes the costs of I/O and time. A CF tree is generated during its working process and clusters are generated after four phases of the whole BIRCH procedure. A drawback of BIRCH is that it is not very scalable. This thesis is devoted to improve accuracy and efficiency of BIRCH algorithm. A sliding window BIRCH algorithm is implemented on the basis of BIRCH algorithm. At the end of thesis, the accuracy and efficiency of sliding window BIRCH are evaluated. A performance comparison among SW BIRCH, BIRCH and K-means are also presented with Silhouette Coefficient index and Calinski-Harabaz Index. The preliminary results indicate that the SW BIRCH may achieve a better performance than BIRCH in some cases.

  • 207.
    Li, Yongwei
    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.
    An analysis of demosaicing for plenoptic capture based on ray optics2018In: Proceedings of 3DTV Conference 2018, 2018, article id 8478476Conference paper (Refereed)
    Abstract [en]

    The plenoptic camera is gaining more and more attention as it capturesthe 4D light field of a scene with a single shot and enablesa wide range of post-processing applications. However, the preprocessing steps for captured raw data, such as demosaicing, have been overlooked. Most existing decoding pipelines for plenoptic cameras still apply demosaicing schemes which are developed for conventional cameras. In this paper, we analyze the sampling pattern of microlens-based plenoptic cameras by ray-tracing techniques and ray phase space analysis. The goal of this work is to demonstrate guidelines and principles for demosaicing the plenoptic captures by taking the unique microlens array design into account. We show that the sampling of the plenoptic camera behaves differently from that of a conventional camera and the desired demosaicing scheme is depth-dependent.

  • 208.
    Li, Yongwei
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Scrofani, Gabriele
    Department of Optics, University of Valencia, Burjassot, Spain.
    Sjöström, Mårten
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Martinez-Corraly, M.
    Department of Optics, University of Valencia, Burjassot, Spain.
    Area-Based Depth Estimation for Monochromatic Feature-Sparse Orthographic Capture2018In: 2018 26th European Signal Processing Conference (EUSIPCO), IEEE conference proceedings, 2018, p. 206-210, article id 8553336Conference paper (Refereed)
    Abstract [en]

    With the rapid development of light field technology, depth estimation has been highlighted as one of the critical problems in the field, and a number of approaches have been proposed to extract the depth of the scene. However, depthestimation by stereo matching becomes difficult and unreliable when the captured images lack both color and feature information. In this paper, we propose a scheme that extracts robust depth from monochromatic, feature-sparse scenes recorded in orthographic sub-aperture images. Unlike approaches which relyon the rich color and texture information across the sub-aperture views, our approach is based on depth from focus techniques. First, we superimpose shifted sub-aperture images on top of anarbitrarily chosen central image. To focus on different depths, the shift amount is varied based on the micro-lens array properties. Next, an area-based depth estimation approach is applied tofind the best match among the focal stack and generate the dense depth map. This process is repeated for each sub-aperture image. Finally, occlusions are handled by merging depth maps generated from different central images followed by a voting process. Results show that the proposed scheme is more suitable than conventional depth estimation approaches in the context of orthographic captures that have insufficient color and feature information, such as microscopic fluorescence imaging.

  • 209.
    Lihv, Rebecca
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Arkivarien som väktare eller facilitator: En samtidshistorisk undersökning av svenska arkivariers professionella identitet2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis examines contemporary professionalism among Swedish archivists and how they create a professional identity and defend their status in a context defined by societal change and a new techonological, political and organizational setting. The results are interpreted using two ideal-types drawn from sociological theory on professional change due to the emergence and incorporation of New Public Management in the public sector. The results show that Swedish archivists tend to defend a traditional role as objective and neutral keepers of truth, but also strive to redefine their professional role within organization as experts of information, leaders and managers. Furthermore, the professional status is strenghtened by defending the archive’s role in society as a memory institution for cultural identity and historical truth as well as an important asset for private enterprise and public sector.

  • 210.
    Lin, Qing
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Wi-Fi File Sharing System for Android2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Many Smartphone users often need to transfer large files to another Smartphone or PC. Today many people are using Bluetooth, USB cable and some phone applications to transfer large files. The problem is that these existing methods for transferring large file are taking too long time, or have some other limitations. To make the file transmission more efficient could help a lot of people. Therefore it is essential to have a better file transmission system to solve this kind of problem. The Objective of this project has been to study and develop an Android mobile application for sending and receiving files to the permitted smartphone in an effective and user-friendly way. The methods being used during this project includes investigation of the existing systems with similar function, user requirement surveys, system and user requirement analysis, iterative development and application evaluation. Data transmission function will be accomplished by the Wi-fi service on the smartphone. The Wi-Fi connection between smartphones is protected by a user-defined password, which could be entered by either manual input or scan QR code generated by this application. The evaluation process carried out is based on performance, functionality and usability test. The result showed that this application is capable of transferring large file between different devices with a user-friendly graphical interface.

  • 211.
    Lin, Yeqiang
    et al.
    Donghua Univ, Dept Comp Sci & Technol, Shanghai, Peoples R China.
    Lavassani, Mehrzad
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Li, Jiyun
    Donghua Univ, Dept Comp Sci & Technol, Shanghai, Peoples R China.
    Zhang, Tingting
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    PixVid: Capturing Temporal Correlated Changes in Time Series2017In: Proceedings - 5th International Conference on Advanced Cloud and Big Data, CBD 2017, 2017, p. 337-342, article id 8026960Conference paper (Refereed)
    Abstract [en]

    Time series is one of the main research domains in variety of disciplines. Visualization is an important mechanism to present the raw data as well as the processed time series for further analysis. Many successful visualization techniques have been reported recently. However, most of these techniques display data statically, intending to show as much information as possible by one image or plot. We propose PixVid, a visualization technique which orders the dimensions by constructing a hierarchal dimension cluster tree, and then uses a pixel-oriented technique to form images and displays the data in video format.

  • 212.
    Lindberg, Gustaf
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Sawert, Marcus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Industri och digitalisering i Västernorrland: En kartläggning2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the study was to map the small and medium sized industrial companies in Västernorrland and their work with digitalization. This was performed with the help of an analysis where data from the companies book keeping were retrieved from a database together with a survey that was sent to the companies. The analysis showed how the industry in Västernorrland looks like considering the development of number of companies, number of employees, revenue and more. The questions of the survey were chosen to fit with indicators from the governmental strategy for the industrial transformation. The results of the survey showed that the most of the respondents work with digitalization to some extent. Production and marketing are the main areas where the companies see the biggest possibilities with digitalization. There are very few women in the industrial companies in Västernorrland, both in general and in leading positions. This is contrary to the fact that women in general have a higher education than men, something that is becoming increasingly important with the expansion of digitalization. Support initiatives in the form of a better cooperation between schools and the industry could solve the supply of competence to the companies. The analysis shows that, except for how the industry presently looks, that it is difficult to draw any conclusions about how the companies work with digitalization. There are tendencies that high-tech companies more often themselves write about their work with digitalization on their websites which can be connected to that these companies work more actively with digitalization compared to low-tech companies.

  • 213.
    Lindberg, Johan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Big Data och Hadoop: Nästa generation av lagring2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The goal of this report and study is to at a theoretical level determine the possi- bilities for Försäkringskassan IT to change platform for storage of data used in their daily activities. Försäkringskassan collects immense amounts of data ev- eryday containing personal information, lines of programming code, payments and customer service tickets. Today, everything is stored in large relationship databases which leads to problems with scalability and performance. The new platform studied in this report is built on a storage technology named Hadoop. Hadoop is developed to store and process data distributed in what is called clus- ters. Clusters that consists of commodity server hardware. The platform promises near linear scalability, possibility to store all data with a high fault tolerance and that it can handle massive amounts of data. The study is done through theo- retical studies as well as a proof of concept. The theory studies focus on the background of Hadoop, it’s structure and what to expect in the future. The plat- form being used at Försäkringskassan today is to be specified and compared to the new platform. A proof of concept will be conducted in a test environment at Försäkringskassan running a Hadoop platform from Hortonworks. Its purpose is to show how storing data is done as well as to show that unstructured data can be stored. The study shows that no theoretical problems have been found and that a move to the new platform should be possible. It does however move handling of the data from before storage to after. This is because todays platform is reliant on relationship databases that require data to be structured neatly to be stored. Hadoop however stores all data but require more work and knowledge to retrieve the data.

  • 214.
    Lindbäck, Mattias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Rutiner för nätverks- och systemmiljödokumentation utifrån ITIL och utvärdering av ITSM/CMDB-program2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today at Höglandets IT (HIT) there are no standards or routines for documenting their network- and system environment. Therefore, the purpose and goal of this work is to investigate and develop routines for how HIT will document their network- and system environment based on ITIL, and evaluate two ITSM/CMDB-software that can be used for this. The study has been carried out using interviews from employees from HIT and own evaluations of ITSM/CMDB-software. The results from the interviews was that the respondents lacked the ability to see relationships between devices and systems, that the quality of the current documentation is mixed and that it is messy along the documentation and difficult to find the documentation. The documentation and features the respondents wanted where: to be able to see relationships, documentation of changes, solution descriptions, system documentation, support tickets connected to devices, search function, mutual location to save the documentation and to automate certain parts of the documentation. It was also found that the amount of time respondents could think of documenting was 10 % of their worktime. The comparison between ITSM/CMDB-software iTop and Freshservice was even and both the software had similar features. One of the big differences between them is that iTop is free, while Freshservice has a monthly fee of $49-79/user. Both software have various automation features but I think iTop has better features to automate some of the documentation. The conclusion is to use iTop and document for instance relationships, solution document, changes, system documentation and then automate more detailed information such as IP and RAM.

  • 215.
    Lindström, Karl
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    A framework for communicating with Android apps from the browser2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    With the recent growth of the mobile market, companies want to target mobile devices while at the same time keeping product development costs low. One way to do this is to develop web applications, which are accessed from a mobile de- vice’s web browser, instead of native applications. The same web application can then be used on different platforms such as Android and iOS. However, devices such as smart phones and tablets often include cameras and sensors that a web ap- plication may want to access, but which are only accessible from native applica- tions. A framework was developed that enables web applications to communicate with native Android applications. Native applications are launched by clicking a link in the browser, and the result produced is made available to the web applica- tion through a HTTP POST request or a local web server running on the device. Key characteristics of the framework include ease of extension and the ability to enable secure (SSL) communication if desired. The ZXing Barcode Scanner ap- plication was integrated with the framework so that a scanned barcode can be dis- played in the browser. Performance measurements were conducted measuring the time taken from clicking a link to start a test application to the result being avail- able in the browser. The mean times measured were between 323 and 394 mil- liseconds. This indicates that the method used is sufficiently fast to not detract from the user experience. Future work could expand on the measurements or per- form a feature and performance comparison with PhoneGap.

  • 216.
    Lindén, Johannes
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Huvudtitel: Understand and Utilise Unformatted Text Documents by Natural Language Processing algorithms2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    News companies have a need to automate and make the editors process of writing about hot and new events more effective. Current technologies involve robotic programs that fills in values in templates and website listeners that notifies the editors when changes are made so that the editor can read up on the source change at the actual website. Editors can provide news faster and better if directly provided with abstracts of the external sources. This study applies deep learning algorithms to automatically formulate abstracts and tag sources with appropriate tags based on the context. The study is a full stack solution, which manages both the editors need for speed and the training, testing and validation of the algorithms. Decision Tree, Random Forest, Multi Layer Perceptron and phrase document vectors are used to evaluate the categorisation and Recurrent Neural Networks is used to paraphrase unformatted texts. In the evaluation a comparison between different models trained by the algorithms with a variation of parameters are done based on the F-score. The results shows that the F-scores are increasing the more document the training has and decreasing the more categories the algorithm needs to consider. The Multi-Layer Perceptron perform best followed by Random Forest and finally Decision Tree. The document length matters, when larger documents are considered during training the score is increasing considerably. A user survey about the paraphrase algorithms shows the paraphrase result is insufficient to satisfy editors need. It confirms a need for more memory to conduct longer experiments.

  • 217.
    Lindén, Johannes
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Forsström, Stefan
    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.
    Evaluating Combinations of Classification Algorithms and Paragraph Vectors for News Article Classification2018In: Proceedings of the 2018 Federated Conference on Computer Science and Information Systems / [ed] Maria Ganzha, Leszek Maciaszek, Marcin Paprzycki, Warzaw: Polskie Towarzystwo Informatyczne , 2018, p. 489-495, article id 8511213Conference paper (Refereed)
    Abstract [en]

    News companies have a need to automate and make the process of writing about popular and new events more effective. Current technologies involve robotic programs that fill in values in templates and website listeners that notify editors when changes are made so that the editor can read up on the source change on the actual website. Editors can provide news faster and better if directly provided with abstracts of the external sources and categorical meta-data that supports what the text is about. In this article, the focus is on the importance of evaluating critical parameter modifications of the four classification algorithms Decisiontree, Randomforest, Multi Layer perceptron and Long-Short-Term-Memory in a combination with the paragraph vector algorithms Distributed Memory and Distributed Bag of Words, with an aim to categorise news articles. The result shows that Decisiontree and Multi Layer perceptron are stable within a short interval, while Randomforest is more dependent on the parameters best split and number of trees. The most accurate model is Long-Short-Term-Memory model that achieves an accuracy of 71%.

  • 218.
    Liu, Honggang
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Research and implementation of an indoor positioning algorithm2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The goal of the Internet of Things’ sensing technology is to provide LBS(location-based services); a key technology is finding out how to positioning the sensing devices. For positioning outdoors, mature tech-nology such as GPS and cellular network location can be used. There is little research about indoor positioning, and there is no finished product on the market.

    This paper shows how to use both Wi-Fi and ZigBee signal for position-ing; Wi-Fi to find the area position and ZigBee to find the coordinate position. The main contribution of this paper is described in the follow-ing:

    This paper will present an algorithm using kNN on a Wi-Fi signal, as a way to find the location area of users. The GPS signal cannot be used indoors, but there are usually numerous Wi-Fi signals, that can be used for indoor positioning. In this design, to build a dataset containing the number of locations and the Wi-Fi signal strength list of each location. When indoor positioning is needed, the KNN algorithm is used to compare the user’s Wi-Fi signal strength with the dataset and find the location number.

    When precise positioning is needed, the ZigBee signal should be used. In this paper two different methods for precise positioning in are used, one is an improved algorithm of triangle centroid algorithm where the positioning accuracy depends on the number of anchor points and the interval of each point. The other method is the neural network method. This method could give stable result with only four anchor points.

    Finally, there is a comparison of the methods mentioned in this paper : the Wi-Fi fingerprint method, the ZigBee triangle centroid algorithm, and neural network method.

  • 219.
    Liu, Jun
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    A Combination method of Fingerprint Positioning and Propagation Model Based localization scheme in 3D Large-Scale Indoor Space2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    To achieve the concrete aim of improving the positioning accuracy for large-scale indoor space in this thesis, we propose a weighted Gaussian

    and Mean hybrid filter (G-M filter) to obtain the G-M mean of received signal strength indicator (RSSI) measurements, which is implemented by taking the practically experimental measurements of received signal strength indicator and analyzing the characteristics of received signal strength indicator. Meanwhile, various path loss models have been utilized to estimate the separation between the transmitting antenna and

    the receiver (T-R separation) by calculating the G-M mean of received signal strength indicator, therefore, a dynamic-parameter path loss model has been proposed which can be appropriate to enhance the accuracy of estimated T-R separation and accurately describe the indoor position. Moreover, an improved fingerprint positioning has been proposed as the basic method combined with our tetrahedral trilateration scheme to reduce the positioning error of a large-scale 3D

    indoor space which can achieve the average localization error of 1.5 meters.

  • 220.
    Liu, Yilin
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Evaluation and Measurement of IoT Gateways2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    With the vigorous development of Internet of things, IoT gateways as the communication bridge of the whole IoT system has attracted more and more people’s attention. So the objective of this project is to measure and evaluate the performance of two kinds of IoT gateways including Arduino Uno and Vinnter IoT gateway. In order to reach this objective, the concrete implementation is to create a demonstrator via JAVA program to establish serial communication and measure the latency and throughput of respective IoT gateways. The measurement is implemented under a specific scenario which is to control the action of an actuator such as a LED connecting with IoT gateways via GPIO pins. Finally, the results will be presented via statistical data and line charts. Through analyzing the results, the performance of these two IoT gateways can be compared in terms of latency and throughput easily. Besides implementing the measurement in practice, this paper also involves the scientific research of many different industrial-level IoT gateways and their performance are compared on both hardware and software sides. Consequently, this thesis will show you the comparison of various IoT gateways both in theory and in practice.

  • 221.
    Liu, Ying
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    REST/HTTP Access to the SensibleThings Platform2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Internet of Things (IoT), also called the Internet of Everything or the Industrial Internet, is a new technology paradigm regarded as a global network of machine and devices capable of interacting with each other. Internet of things (IoT) is closely related to numerous fields. The IoT platform is a suite of components that enable deployment of applications, independent and secure connectivity between devices, device/sensor management and integration with 3rd party systems. With increased demand of utilize the platform by web access, the task of this thesis is to develop a RESTful web service for specific IoT platform – SensibleThings platform using Jersey framework. Then measuring the web server under two scenarios and evaluating. Finally, I present the future work for the RESTful web service to improve its functions.

  • 222.
    Ljung, Isac
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Kollen - Personhantering2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport handlar om ett projekt att ta fram en webbapplikation kallad Kollen som ska hjälpa församlingar i Sverige att hantera information om sina egna medlemmar. Kollen ska underlätta för församlingar att spara uppgifter om sina medlemmar på ett enkelt och säkert sätt i webbläsaren. Rapporten beskriver den process från undersökning av de behov som finns till att skapa en applikationen som bemöter dessa behov på ett enkelt och tillfredställande sätt. Kollen applikationen ska vara skapad säker, intuitiv och modern. I diskussion kan vi läsa om hur Kollen bemöter mycket av de behov som fanns utifrån den intervju som gjordes. Men det finns mycket som kan önskas i framtida uppdateringar då det finns fortfarande mycket kvar som församlingar önskar.

  • 223.
    Lo Bello, Lucia
    et al.
    University of Catania, Italy.
    Åkerberg, Johan
    ABB Corporate Research, Sweden.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Uhlemann, Elisabeth
    Mälardalen University.
    Guest Editorial Special Section on New Perspectives on Wireless Communications in Automation: From Industrial Monitoring and Control to Cyber-Physical Systems2017In: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050, Vol. 13, no 3, p. 1393-1397, article id 7938563Article in journal (Refereed)
  • 224.
    Lu, Lu
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    IoT Network Watchdog2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Internet of Things (IoT) plays an important role in the coming era of the Internet development. In addition to the convenience and opportunities it brings to us, there comes with the security issues, which could lead to the privacy leakage, it’s a threaten to the whole IoT system. To deal with the potential dangerous element hidden behind this technology, monitoring on the network would be indispensable. To develop and implements the digital network watchdog system that monitors the local network and the connected device, firstly, I surveyed the area related to the IoT attacks. The network monitor system provides basic network monitoring function, connected device tracking and monitoring function, reliable device operating function. I used the packages provided by Raspberry Pi to realize the general monitoring and transferred the captured result for further analysis. Also, I made use of SNMP and drawing tool to create graphs of different parameters in the monitoring of both network and connected devices. Then I implemented database with web service on Raspberry Pi to realize device operating. In evaluation, the system works well in general monitoring with all information provided and low lost package percentage, the graphs can provide situation of different parameters, and the respond time in the operation time of database is short. I discussed the ethical thinking and proposed the ethical thinking and future work.

  • 225.
    Lundström, Adam
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Arkitektonisk utformning av en lagringsplattform för Business Intelligence: En litteratur- och fallstudie riktad mot små och medelstora företag2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    BI, business intelligence, which means to collect and analyse data to inform business decisions, is a concept that has grown to be a significant part of business development. In most cases, a storage platform is necessary to provide data from the companies’ different data sources to the BI-tools. There are different ways of doing this. Some of them are by the help of a data lake, a data warehouse or a combination of both. By taking this into consideration the purpose of this study is to create an architectural design of a storage platform for small and medium-sized enterprises (SME). To be able to formulate a result which holds as high validity and reliability as possible, this study conducts both a literature and a case study. The case study has taken place at an IT service company which classifies as a SME and the working methodology has been an agile approach with scrum as reference. This method was chosen to be able to efficiently follow the customer demands.  The architecture provided consists of a combination of a data hub, which acts as a data lake, and a data warehouse. The data hub differs from a data lake by harmonizing and indexing data, which makes it easier to handle. Regarding the intension of the data warehouse, it is to yield relevant and processed data to BI-tools. The architecture design of the platform that has been developed in this study cannot be said to be applicable by all companies. Instead, it can be a basis for companies that are thinking about creating a data platform.

  • 226.
    Lönngren, Josefin
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Fahlén, Sandra
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Utmaningar och möjligheter i upphandlingsprocessen - för att kunna digitalisera på ett innovativt sätt i offentlig verksamhet2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Approximately, digital transformation in public sector is procured for an amount of 59 billion Swedish crowns, according to Konkurrensverket. But despite this, the procurement process is not that effective, which may question the benefits of the investment being made. The Swedish Government has a goal to be the best in the world to utilize the opportunities that digitalization gives to the public sector, but according to Ekonomistyrningsverket, this goal is not considered to be fulfilled since there are some shortcomings in the area. Some argue that public procurement of innovation can contribute to a solution that is better suited to public needs, which is one of the reasons that the agency of innovation Vinnova was commissioned by the government to promote public procurement of innovation in the public sector. The procurement process is governed by laws and therefore the communication between customer and supplier is limited as no supplier are allowed to have competitive advantages in the procurement. This means that the requirement specification is important for public sector to fill their needs, but it claims that the process of requirements can be very complicated. The purpose of the study is to deepen the knowledge of procurement as an aspect to digitalize in an innovative way. This will be done by identifying the challenges and opportunities that exists in the procurement process. The study is conducted through an qualitative method and a literature study and interviews are used to collect data. Initially, the area is explored in a broader perspective with an exploratory approach and the collected material are further specified into a more specific area where a more focused approach is used. The results of the study indicate that there are both challenges and opportunities in the procurement process. The challenges that were identified concern the areas; specification of requirements, limits with the Public Procurement Act (PPA), the concept & meaning of public procurement of innovation and the competence of the Swedish innovation agency. Furthermore, the possibilities that were identified concern the areas; the competence of the Swedish innovation agency, specification of requirements, PPA & new way of working with the procurement process and the trend of being innovative.

  • 227.
    Lövgren, Magdalena
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Kriterier för säkerhetskopiering i molnet: En fallstudie med Amazon Web Service2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Backup is a way of protecting data through copying and saving data on for an example hard drives, external servers or in the cloud. To save the backup on local servers can be a costly solution for business and organisations since the cost of buying servers, installation and maintenance may cause the cost to increase. With backups in the cloud some of that cost disappears as no servers needs to be bought and without the need for servers there is no need for maintenance like installation, change of hardware etcetera. This is because all of that is taken care of by the cloud service provider. But there are a lot of things to consider before moving to the cloud. Things such as cost, security, topology and the option to automatizate the backup could all affect the choice of cloud service. This is why it is of a great importance to have security in mind since the data that backups could contain sensitive information that could harm the business or organisation, if leaked. This report has the purpose to produce information regarding backups and cloud services for business and organisations that are at a crossroad trying to pick a cloud service provider. The focus of the report lies on cost, security and to automate the process of backups to the cloud. Therefore the report is suited for business that are interested in cloud services and that are on the lookout for information on what is important to think about before they choose a cloud service provider. The security analysis will consist of a risk analysis that is using the study done by Cloud Security Alliance as a base. They have through a study produced a paper on the twelve most common risk with cloud services, there will be evaluated in the report and placed on a matrix. By comparing the risk and drawing parallels to existing cloud service providers it looks to give the reader more knowledge around risks in cloud services and how to avoid them. Further the criterias for the cloud services will be brought up and compared through a staple diagram which will then be discussed. The criterias was made through searches via a search engine using a phrase to see what writers and companies thought were the most important criterias. The cost of the cloud services was done through a comparison between different cloud service provider and their cloud services. A user-case scenario was made based on the practical parts of the study where costs such as GB per download and request were part of the final yearly cost for each of the cloud service. Lastly there’s a script for the backup to demonstrate how a backup solution in a cloud could look like. This is done through working with the tool Amazon Web Service (AWS) in a virtual environment that would backup to AWS. Bigger parts of the inquiry shows that security is often overlooked which is part of the conclusion in the report. Both the criteria and the risk-analysis in the report lifts the security aspects as one of the most important part of cloud services. For criterias it shows topology as the most important aspect in choosing a cloud service, security and support being second. Furthermore the risk analysis brought up the lack of security in cloud services and gives examples from real life events where big companies have had their security breach. More knowledge is needed when it comes to security, for a lot of companies and organisation since they can often overlook security in favor of a simpler solution. Even though security is one of the most important aspects when choosing a cloud service and should be treated as such. Despite the lack of security being brought up in the report it seems there are a lot of tools to work with within the cloud services, as long as the will exist to work with these tools. It is not the lack of tools but rather the ignorance or lack of understanding of security that is the cause of the problem. As for the cost it turns out to not be such a big difference, it is only ranked as the third most important thing when choosing a cloud service and during the comparison it shows that most cloud services sticks to similar prices as their competition. The ethical aspects in the report is about responsibility and the question on who is responsible is brought up. Here the argument is about whether or not it is the cloud service providers responsibility to make sure their users understand the security tools they provide or to make sure they are enforced. Or if it is the users responsibility to make use of the tools they are given and to not think too lightly of security.

  • 228.
    Ma, Jian
    et al.
    Beijing Jiaotong University, Beijing, China.
    Yang, Dong
    Beijing Jiaotong University, Beijing, China.
    Wang, Hongchao
    Beijing Jiaotong University, Beijing, China.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    An Efficient Retransmission Scheme for Reliable End-to-End Wireless Communication over WSANs2018In: IEEE Access, E-ISSN 2169-3536, Vol. 6, p. 49838-49849Article in journal (Refereed)
    Abstract [en]

    Wireless sensor and actuator network (WSAN) is increasingly recognized as an important technology in the realization of the future Internet of Things (IoT). The ability to cater to the demands of real-time, reliable and resource-constraint communication in industrial areas is highly dependent on efficient scheduling of communication links. Harsh industrial environments make packet retransmission inevitable, which causes the waste of link resource and deteriorates the reliability. Most of researches that focus on real-time and reliable performance underestimate the complexity of packet retransmission. Therefore, this paper proposes an efficient retransmission scheme to guarantee deterministic communication and decrease the resource utilization. We combine deterministic communication with a novel reliable method by proposing a flow-based slot scheduling with a concession timeslot assistant. The proposed concession slot works by using the CCA and the pre-signal to avoid the contention of one channel during the communication on shared links. Furthermore, we use the theory of discrete-time Markov chain to analyze another two randomly backoff-based and flow-based shared link schedules. This study demonstrates that the proposed retransmission scheme can significantly improve the reliability of end-to-end packets delivery and the efficiency of slot utilization, as well as decrease energy consumption. The proposed scheduling is applied in a real factory, where the efficiency of the slot is significantly improved, and a flow reliability of 95.3% under a 12% packet error rate is guaranteed. 

  • 229.
    Ma, Jian
    et al.
    Beijing Jiatong University, China.
    Yang, Dong
    Beijing Jiatong University, China.
    Zhang, Honke
    Beijing Jiatong University, China.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    A Reliable Handoff Mechanism for Mobile Industrial Wireless Sensor Networks2017In: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 17, no 8, article id 1797Article in journal (Refereed)
    Abstract [en]

    With the prevalence of low-power wireless devices in industrial applications, concerns about timeliness and reliability are bound to continue despite the best efforts of researchers to design Industrial Wireless Sensor Networks (IWSNs) to improve the performance of monitoring and control systems. As mobile devices have a major role to play in industrial production, IWSNs should support mobility. However, research on mobile IWSNs and practical tests have been limited due to the complicated resource scheduling and rescheduling compared with traditional wireless sensor networks. This paper proposes an effective mechanism to guarantee the performance of handoff, including a mobility-aware scheme, temporary connection and quick registration. The main contribution of this paper is that the proposed mechanism is implemented not only in our testbed but in a real industrial environment. The results indicate that our mechanism not only improves the accuracy of handoff triggering, but also solves the problem of ping-pong effect during handoff. Compared with the WirelessHART standard and the RSSI-based approach, our mechanism facilitates real-time communication while being more reliable, which can help end-to-end packet delivery remain an average of 98.5% in the scenario of mobile IWSNs.

  • 230.
    Magnusson, Fredrik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Implementing a Backup-Scheme with the 3-2-1 Strategy: A Comparison of the Active Solution with a New Implemented 3-2-1 Backup-Scheme2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report handles the theory behind probability, backups and hard drives. Based on this, a backup-scheme is implemented with the help of NASes, to replace the current solution. The need for a more secure, more reliable and a solution that is expandable due to the quick growth of the company, was put forward together with a budget to provide a solution suited after the effective need. This scheme is based upon theory in combination with third-party results and for this specific case has the budget, provided by the company, as a starting point to accomplish a sustainable, expandable and automated backup. Furthermore, this report implements this solution into the existing infrastructure where automation and simple handling of backups and why a 3-2-1 solution will be used. The report finds that after the new solution is implemented there is significantly less risk of data failure as well as an overall increase in speed and automation. Finally, with the help of standardized tools this report lay a decent groundwork for others to use in their implementation or to dig deeper into the world of reliability.

  • 231.
    Mahmood, Aamir
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Ashraf, Ikram
    University of Oulo and Ericsson Research, Finland.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Torsner, Johan
    Ericsson Research, Finland.
    Over-the-Air Time Synchronization for URLLC: Requirements, Challenges and Possible Enablers2018In: Proceedings of the International Symposium on Wireless Communication Systems, IEEE, 2018, article id 8491188Conference paper (Refereed)
    Abstract [en]

    Ultra-reliable and low-latency communications (URLLC) is an emerging feature in 5G and beyond wireless systems, which is introduced to support stringent latency and reliability requirements of mission-critical industrial applications. In many potential applications, multiple sensors/actuators collaborate and require isochronous operation with strict and bounded jitter, e.g., 1µs. To this end, network time synchronization becomes crucial for real-time and isochronous communication between a controller and the sensors/actuators. In this paper, we look at different applications in factory automation and smart grids to reveal the requirements of device-level time synchronization and the challenges in extending the high-granularity timing information to the devices. Also, we identify the potential over-the-air synchronization mechanisms in 5G radio interface, and discuss the needed enhancements to meet the jitter constraints of time-sensitive URLLC applications.

  • 232.
    Mahmood, Aamir
    et al.
    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.
    Renewal-theoretic Packet Collision Modeling under Long-tailed Heterogenous Traffic2017In: 28th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC'17), Montreal, Canada, Oct. 2017., IEEE, 2017Conference paper (Refereed)
    Abstract [en]

    Internet-of-things (IoT), with the vision of billions of connected devices, is bringing a massively heterogeneouscharacter to wireless connectivity in unlicensed bands. The heterogeneity in medium access parameters, transmit power and activity levels among the coexisting networks leads to detrimental cross-technology interference.The stochastic traffic distributions, shaped under CSMA/CA rules, of an interfering network and channel fading makes it challenging to model and analyze the performanceof an interfered network. In this paper, to study the temporal interaction between the traffic distributions of two coexisting networks, we develop a renewal-theoretic packet collision model and derive a generic collision-time distribution (CTD) function of an interfered system. The CTD function holds for any busy- and idle-time distributions of the coexisting traffic. As the earlier studies suggesta long-tailed idle-time statistics in real environments, the developed model only requires the Laplace transform of long-tailed distributions to find the CTD. Furthermore,we present a packet error rate (PER) model under the proposed CTD and multipath fading of the interfering signals. Using this model, a computationally efficient PERapproximation for interference-limited case is developed to analyze the performance of an interfered link.

  • 233.
    Mahmood, Aamir
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Hossain, M. M. Aftab
    KTH Royal Institute of Technology.
    Gidlund, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Cross-Layer Optimization of Wireless Links under Reliability and Energy Constraints2018In: IEEE Wireless Communications and Networking Conference, WCNC, New York: IEEE, 2018Conference paper (Refereed)
    Abstract [en]

    The vision of connecting billions of battery operated devices to be used for diverse emerging applications calls for a wireless communication system that can support stringent reliability and latency requirements. Both reliability and energy efficiency are critical for many of these applications that involve communication with short packets which undermine the coding gain achievable from large packets. In this paper, we study a cross-layer approach to optimize the performance of low-power wireless links. At first, we derive a simple and accurate packet error rate (PER) expression for uncoded schemes in block fading channels based on a new proposition that shows that the waterfall threshold in the PER upper bound in Nakagami-m fading channels is tightly approximated by the m-th moment of an asymptotic distribution of PER in AWGN channel. The proposed PER approximation establishes an explicit connection between the physical and link layers parameters, and the packet error rate. We exploit this connection for cross-layer design and optimization of communication links. To this end, we propose a semi-analytic framework to jointly optimize signal-to-noise ratio (SNR) and modulation order at physical layer, and the packet length and number of retransmissions at link layer with respect to distance under the prescribed delay and reliability constraints.

  • 234.
    Mahmood, Aamir
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Jäntti, Riku
    Aalto University, School of Science and Technology, Department of Communications and Networking, Finland .
    Packet Error Rate Analysis of Uncoded Schemes in Block-Fading Channels using Extreme Value Theory2017In: IEEE Communications Letters, ISSN 1089-7798, E-ISSN 1558-2558, Vol. 21, no 1, p. 208-211, article id 7583696Article in journal (Refereed)
    Abstract [en]

    We present a generic approximation of the packet error rate (PER) function of uncoded schemes in the AWGN channel using extreme value theory (EVT). The PER function can assume both the exponential and the Gaussian Q-function bit error rate (BER) forms. The EVT approach leads us to a best closed-form approximation, in terms of accuracy and computational efficiency, of the average PER in block-fading channels. The numerical analysis shows that the approximation holds tight for any value of SNR and packet length whereas the earlier studies approximate the average PER only at asymptotic SNRs and packet lengths.

  • 235.
    Martinez, Oscar
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Wenner, Veronica
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Strategisk, kulturell och kundbaserad affärsmodellsutveckling: Bredbandsmarknaden under disruptiv förändring2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 236.
    Mazaheri, Shima
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Indoor navigation2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In our day to day activity, imagine if you go to a museum, hospital or any kind of huge building. You need to find the best way to get into a specific depart- ment. It might be difficult to find the way even if you have the map of the building in your hand. Indoor positioning systems can be used to locate people or objects inside a building, using radio waves, signals, or other sensory information collected by a smartphone or tablet. Bluetooth Low Energy (BLE) beacons broadcast signals, and bluetooth devices, such as smartphones, can then receive these signals. BLE devices can take Received Signal Strength Indication (RSSI) information together with an algorithm to calculate the location of the user. This is a useful method for indoor environments when using Global Positioning System (GPS) is not an option [1]. In this project I tried to find a better solution for localization and navigation when GPS does not work. The focus of the project is to use communication be- tween smartphones and beacons, for guidance in inside environments, without using GPS. This thesis is about the applications I produced, which can be used for indoor localization and navigation. Using the applications, you can map any building such as university, hospital, museum, big mall etc. To map a building, you upload a map of the building and put waypoints where you placed beacons. Once mapping is done, you can log in to the web admin and put some informa- tion for each beacon. As a user, when outside a nearby mapped building, your phone can get notified (trough bluetooth), and you can download the user app, which includes the map of the building and shows your location. With the user app you can easily find your favorite places in the building and get information about place near you.

  • 237.
    Min, Menglei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Evaluation and Implementation for Pushing Automatic Updates to IoT Devices2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In recent years, Internet of Things has developed rapidly, and now has penetrated into human life and industrial production. It is speculated that the internet of things will become ubiquitous in the future, which will bring a series of problems. First, the large number of things will lead to operated system and software updates consuming a lot of manpower and resources. Another problem is the Internet of things facing security issues, in recent years for the means of Internet of things and tools have been increasing largely. Therefore, to achieve a secure automatic update on the Internet of Things is essential. This report will follow such an automatic update system based on Internet of things to expand. First it elaborated on the main motive of this problem, found three existing related works and three security methods for communication to analyze. Then combined results of analysis, put forward own a secure automatic update solution: manager and devices connect and mutual authentication in real time, at the same time, the manager will regularly check the database to see if there is new version application. When the administrator uploads a new version, the manager will download the version and then sends to all devices, then device installs and finally restart itself. Next, the report described how to implement this system in detail and evaluated it. In the end, this report summarized and introduces the future work.

  • 238.
    Mohammadi Limaei, Soleiman
    et al.
    University of Guilan, Iran.
    Lohmander, Peter
    Optimal Solutions; Linnéuniversitetet.
    Olsson, Leif
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Dynamic growth models for continuous cover multi species forestry in Iranian Caspian forests2017In: Journal of Forest Science, ISSN 1212-4834, E-ISSN 1805-935X, Vol. 63, no 11, p. 519-529Article in journal (Refereed)
    Abstract [en]

    This study concerns some of the relevant topics of the Iranian Caspian forestry planning problem, in particular the first central components in this modelling process, such as forest modelling, forest statistics and growth function estimations. The required data such was collected from Iranian Caspian forests.  To do so, 201 sample plots were determined and the parameters such as number of tree, tree diameter at breast height  and trees height were measured at each sample plot. Three sample plots at different 3 elevations were chosen to measure the tree increment. Data has been used to estimate a modified logistic growth model and a model that describes the growth of basal area of individual trees as a function of basal area. General function analysis has been applied in combination with regression analysis. The results are interpreted from ecological perspectives. Furthermore, a dynamic multi species growth model theory is developed and analyzed with respect to dynamic behavior, equilibria, convergence and stability. Logistic growth models have been found useful in continuous cover forest management optimization. Optimization of management decisions in a changing and not perfectly predictable world should always be based on adaptive optimization.

  • 239.
    Mohammadi, Zohreh
    et al.
    University of Guilan, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Lohmander, Peter
    Optimal Solutions; Linnéuniversitetet.
    Olsson, Leif
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Estimating the aboveground carbon sequestration and its economic value: case study: Iranian Caspian Forests2017In: Journal of Forest Research, ISSN 1341-6979, E-ISSN 1610-7403, Vol. 63, no 11, p. 511-518Article in journal (Refereed)
    Abstract [en]

    The aim of the study is to estimate the aboveground carbon sequestration and to determine the economicvalue of forests in carbon sequestration as a way of mitigating climate change. This research was conductedat Asalem forests in the north of Iran. In order to estimate the amount of annual carbon sequestration, theannual volume growth of stand was determined using the diameter increment data and tariff. The amount ofcarbon sequestration was estimated based on wood density and using the allometric equation. The carbonmodel was obtained for each species. The value of sequestrated carbon in stumpage and the net present valueof carbon sequestration were determined in order to estimate the economic value of carbon sequestration.Results indicated that the annual volume growth per hectare and the carbon stored are 6.023 m3·yr–1 and2.307 t·ha–1, respectively. Finally, the carbon sequestration value of stumpage and the net present value ofcarbon sequestration are 11,023.753 and 790.361 (10,000 IRR·t–1·ha–1), respectively. Our results are very usefulin estimating the total economic value of Asalem forests and other Iranian Caspian forests in the future.

  • 240.
    Mohammadi, Zohreh
    et al.
    University of Guilan, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Lohmander, Peter
    Optimal Solutions in Cooperation with Linnaeus University, UmeåSweden.
    Olsson, Leif
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Estimation of a basal area growth model for individual trees in uneven-aged Caspian mixed species forests2018In: Journal of Forestry Research, ISSN 1007-662X, E-ISSN 1993-0607, Vol. 29, no 5, p. 1205-1214Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to estimate a basal area growth model for individual trees in uneven-aged Caspian forests. A survey was conducted in order to find a natural forest without any harvesting activities, a so called ‘untouched forest’ and an area was selected from the Iranian Caspian forest. Three sample plots in the same aspect and of the same forest type were selected. In each plot, total tree height, diameter at breast height, distance of neighbor trees and azimuth were measured. Thirty trees were selected and drilled with increment borer to determine the increment model. Regression analysis was used to estimate the growth model. Results show that, for individual trees, there is a significant nonlinear relationship between the annual basal area increment, as the dependent variable, and the basal area. The results also show that the basal area of competing trees has a positive influence on growth. That the increment is higher with more competing neighboring trees is possibly because plots with higher volume per hectare and more competition, most likely also have higher site index or better soil or better site productivity than the plot with lower volume per hectare.

  • 241.
    Mohammadi, Zohreh
    et al.
    University of Guilan, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Lohmander, Peter
    Optimal Solutions; Linnéuniversitetet.
    Olsson, Leif
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Estimation of growth model in uneven – aged forests: Case study: Iranian Caspian forests)2017Conference paper (Refereed)
    Abstract [en]

    The aim of this study was to estimate a diameter growth model for individual trees inuneven –aged Caspian forests. Three sample plots in the same aspect and of the same foresttype were selected. In each sample plot, full callipering was conducted and the parameterssuch as total tree height, diameter at breast height, distance of neighbor trees and azimuthwere measured. In each plot, 30 trees were selected and drilled with increment borer, inorder to determine the growth model. Regression analysis was used to estimate the growthmodel. The analysis shows that, for individual trees, there is a strongly significant nonlinearrelation between the annual basal area increment, as the dependent variable, and the basalarea of the individual trees. The results also show, that the basal area of competing trees, inthe sample, has a positive influence on growth. The estimated result that increment is higherwith more competing neighbor trees is probably obtained because of the following reason:The plots with higher volume per hectare, and more “competition”, most likely also havehigher “site index” or “better soil” or “better forest production conditions” than the plotwith lower volume per hectare.

  • 242.
    Molin, Magnus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Ett webbaserat administrationssystem2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Målet med detta projekt var att skapa en prototyp av ett webbaserat administrationssystem

    till företaget Discovery Networks Sweden som kan hjälpa dem att

    effektivisera deras nuvarande system. I denna rapport går jag igenom hur jag

    skapade sidan efter kundens önskemål. Jag går igenom skapandet av en databas

    över företaget och hur jag skapade alla funktioner som skulle implementeras efter

    önskemål. Jag går också igenom lagar och restriktioner som Discovery Networks

    Sweden är bundna till i deras system.

    Resultatet blev ett dynamiskt system där alla anställda är med och dokumenterar

    deras egna arbete som hjälper till att skapa ett system där anställda har tillgång

    till olika information beroende på vem som är inloggad. Det som kan vara

    intressant för Discovery Networks Sweden att ta med sig och utveckla vidare

    från systemet är att säljarna dokumenterar större del av sitt dagliga arbete vilket

    gör att de har tillgång till information som gör att de kan effektivisera sina dagliga

    rutiner, dessutom kan säljchefen lättare vägleda säljarna då den personen

    har större tillgång till hur säljarna arbetar och deras resultat på daglig basis.

  • 243.
    Nilsson, Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Rydergren, Jonas
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Flödeseffektivisering genom metoder för effektivitetsberäkning och processkartläggningar: En fallstudie på ett massproducerande företag2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today it is important for production companies to create an overview of how the company is conducted to maintain its competitiveness. Mapping processes and material flows visualize production areas that create a direct value for the customer, while remaining areas or activities that do not add a direct value  should be minimized or eliminated. In order to identify material flows and non- value creation activities, complex models are required that can be combined in different ways. The study is based on a case study of an international mass-producing company that is partly located in the middle of Sweden. The factory studies four production lines, each producing the same product type but of different sizes. The aim of this survey is to create a deeper insight in a production process cost and material flows by combining a process-calibration method with methods for calculating the efficiency of processes. The first model used is a mapping process and material flow model to shorten lead times. The 2nd model used is a model that graphically shows which value and non-value creation activities to use the result in an efficiency calculation. The result consists of efficiency calculation, which shows that production Line 1 was streamlined by 19.12%, Line 2 by 6.68%, Line 3 by 18.73% and Line 4 by 4.77%. The goal of efficiency calculations is to achieve an optimal method where the efficiency is 100%.

     

  • 244.
    Nilsson, Frida
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Vad grundar arbetstagare sin informationsförvaltning på?: En kvalitativ studie för att öka förståelsen kring arbetstagaresyrkesmässiga informationsförvaltning.2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Studiens syfte är att öka förståelsen runt hur den enskilda arbetstagaren hanterar sininformationsförvaltning, vilket mynnade ut till forskningsfrågan; Vad arbetstagare på svenskaorganisationer/verksamheter grundar sitt yrkesmässiga bevarande på. För att angripaproblemområdet utfördes kvalitativa semi-strukturerade intervjuer av fyra arbetstagare verksammapå olika platser i mellansverige. Ett bekvämlighetsurval tillämpades genom författarens kontakter,där två av respondenterna arbetade inom den offentliga sektorn och två arbetade inom det privata.Studiens teoretiska referensram grundar sig på den tredje generationens aktivitetsteori; Engeströmsverksamhetsteori, i form av en analys utav respondenternas verksamhetssystem och dess sexknutpunkter. Vidare tillämpades även Records Continuum-modellen för att belysa hur informationhanteras och sprids. Studien tolkas genom en hermeneutistisk metodansats och den hermeneutiskaspiralen. Då metoden endast belyser forskarens tolkning av respondenternas verklighet blir därförnågon generalisering inte möjlig. Detta eftersom det enbart är respondenternas upplevelser avfenomenet som redovisas.De kvalitativa intervjuerna transkriberades och färgkodades för att sedan delas upp i olika temansom utformade resultatet. Genom att studien utgår från en hermeneutisk tolkning avrespondenternas berättelser, redovisas därav endast tendenser, vilket förhoppningsvis kan kommaatt väcka intresse för vidare forskning.Resultatet visade att det råder en värderingsproblematik hos respondenterna vilket förvärras avtidsbrist. Detta försvårar arbetstagares informationsförvaltning som saknar utvecklade och mertydliga rutiner och mallar över hur informationsförvaltning och värdering av information bör gå till.Resultatet pekar även på att mycket information sparas utanför verksamhetens nätverk och system, iform av e-postmeddelanden och personliga anteckningar och dokument, vilket kan leda till attinformation inte tilldelas alla i verksamheten. Att informationen inte förs in i systemen ellerredovisas menar respondenterna ofta är mycket på grund av tidsbrist då de inte hinner hanterakomplicerade system och mallar samt för att det fattas direktiv över hur och var information skabevaras.

  • 245.
    Nilsson, Joel
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    The Majo programming language: Creation and analysis of a programming language for parallelization2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    It is well known that parallelization of software is a difficult problem to solve. This project aimed to research a possible solution by creating a programming language for parallelization and subsequently analyzing its syntax and semantics. This analysis consisted of readability and writability tests followed by a subjective discussion from the point of view of the author. The project resulted in the Majo programming language. Majo uses a graph based concurrency model with implicit shared data synchronization. The model is integrated into the languages design, making it easier to use. The analysis of the language showed that the integration of the threading model simplifies the writing of parallel software. However, there are several syntactic elements that could be improved upon, especially regarding the communication between concurrently executing threads. In conclusion, the author believes that the way forward in regards to parallel programming is to make programming languages more human centric and design syntax in a way that intuitively expresses the underlying semantics.

  • 246.
    Nilsson, Linus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Quality and real-time performance assessment of color-correction methods: A comparison between histogram-based prefiltering and global color transfer2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the field of computer vision and more specifically multi-camera systems color correction is an important topic of discussion. The need for color-tone similarity among multiple images that are used to construct a single scene is self-evident. The strength and weaknesses of color- correction methods can be assessed by using metrics to measure structural and color-tone similarity and timing the methods. Color transfer has a better structural similarity than histogram-based prefiltering and a worse color-tone similarity. The color transfer method is faster than the histogram-based prefiltering. Color transfer is a better method if the focus is a structural similar image after correction, if better color-tone similarity at the cost of structural similarity is acceptable histogram-based prefiltering is a better choice. Color transfer is a faster method and is easier to run with a parallel computing approach then histogram-based prefiltering. Color transfer might therefore be a better pick for real-time applications. There is however more room to optimize an implementation of histogram-based prefiltering utilizing parallel computing.

  • 247.
    Nilsson, Marita
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Proveniensprincipen: Vara eller icke vara - det är frågan i en digitaliseradinformationsförvaltning2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This essay describes the debate about the principle ofprovenance and its multiple forms, and the transformationsof these forms, due to the coming of electronic informations.The thesis intended to explain the definitions of the principlein a modern information management and there explore howthey operate proactively to assure provenance.The qualitative investigation was carried out at tenmunicipality final archives, where each municipalityarchivist was being interviewed. The study expounds in whatway the digitisation has simplified the methods to conductassured provenance, where automated metadata shows therelationships of the information to function and process. Theessay also debates the difficulties that appear when digitalinformation are being organized in different ways thananalogue information, and how this fact requires a newinterpretation of the principle of provenance.The researcher concludes that the investigated archives,ensure respect des fonds when it concerns the content of thearchives, but not when it comes to the whole content of theinformation management. The result of the study also showsthat the respect of original order as a reflection of theorganization, has to be understood throughout all content ofthe management and its logical order, rather than the visiblecontent that the archives embrace. Furthermore the thesisobserves the importance of proactivity, regarding theclarification of the relationships between the information andthe processes that produce and use them. This could beachieved with early application of metadata and developmentof systems that keep metadata trough all processes. Theconclusion of the essay is that this is not pursued in theextension that is required.

  • 248.
    Nilsson, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    3D-visualisering av webbplats i realtid2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this study a 3D-application was developed to use for visualizing a website and its visitors in real time. The 3D application was developed to be used in websites developed in the CMS Episerver. This study has investigated the benefits of being able to see how website visitors navigate between webpages in real time, how scalable the implemented 3D application is, if its possible to develop a 3D application that can be implemented in Episerver websites and what the benefits of using 3D compared to 2D or text logs for the end user are. The 3D visualisation was built using the JavaScript library Babylon.js and works by modifying the Episerver Controller class to store relevant visitor data each time a visitor makes a HTTP request to the webserver. The data is then used with Babylon to render animations and visitor representations in the 3D application. Results show that a real time view of a website can be beneficial to be able to see load distribution, where visitors are positioned before restarting the server, to be used in user tests and in customer service cases and that the majority of questioned webadministrators thinks that it would be beneficial to be able to see their visitors in real time. Results also show that the application is not very scalable and that the use of 3D may not be beneficial for the end user. Finally recommendations for future development is presented and discussed.

  • 249.
    Norberg, Simon
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Wie, Wilhelm
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    How blockchain can increase food supply chain management actors’ competitiveness2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Fresh fish logistics is a complex and demanding supply chain. To add to this, consumers all over the world are increasingly concerned with food safety, environmental sustainability, and ethical production. On a global scale, the seafood industry handles close to 160 million metric tons annually, and approximately 20 percent of this is spoiled before reaching an end customer. Lately, there has been a lot of favorable discussions and fruitful experiments with regards to basing the supply chain on blockchain technology. Through a combination of a structured literature review and a SWOT analysis on the fresh fish supply chain, this thesis aims to review blockchain technology’s current status in the logistics industry, specifically food supply chain management, and evaluate advantages and disadvantages pertaining to the implementation and operation of a blockchain-based fresh fish supply chain management solution. Furthermore, this thesis seeks to initiate a general discussion on the applicability of blockchain on fresh fish food supply chain management systems.

    While blockchain might, at first glance, seem as the ideal solution to today’s challenges, a blockchain based supply chain in the fresh fish industry is facing several challenges of its own which it needs to overcome in order to make it suitable for wide-scale implementation.

  • 250.
    Norberg, Zara
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    L2L-konnektivitet över L32018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Projektets syfte var att sätta upp två typer av tunnlar, L2TPv3 och VPN IPsec, och jämföra dessa med avseende på genomströmningshastighet, tidsåtgång och funktionalitet, detta för att komma fram till om L2TPv3 är en godtagbar utökning av produktportföljen för företaget. Dessa tunnlar konfigurerades på två brandväggar av märke Clavister E80. Genomströmningshastighetstesterna utfördes med IPERF över TCP och UDP och funktionaliteten utvärderades teoretiskt.

    De två teknikerna har samma säkerhetsfunktionalitet och samma möjlighet att låta ett regelverk hantera trafiken mellan orterna, trots att enheterna i L2TPv3-fallet sitter på samma subnät. Den största skillnaden ligger i att L2TPv3 kan hantera att tunnla vilken payload som helst över IP och tillåter samma nät på båda sidor. Genomströmningshastigheten (över TCP) är betydligt högre över VPN IPsec med anledning av L2TPv3:s inkapsling och paketstorlek. Tidsåtgången för uppsättning uppskattas till det dubbla för L2TPv3 då fler variabler behöver beaktas (och även konfigureras), bland annat vilka applikationer som ska köras över tunneln och hur IP-tilldelning ska fungera. Vilken teknik som är lämplig beror på hur kundens miljö ser ut, det faktum att det just nu saknas stöd för HA och IPv6 (i cOS Core) måste tas hänsyn till, och vilken funktionalitet som efterfrågas. L2TPv3 ger L2L-konnektivitet genom att sträcka ut L2 över L3, och om det från kundens sida är önskvärt att enheter på båda sidor om tunneln ska bete sig som om de satt på samma LAN så är det i relation till MPLS, svartfiber och SD-WAN en kostnadseffektiv och relativt simpel lösning.

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