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  • 1.
    Abbas, Nadeem
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Designing Self-Adaptive Software Systems with Reuse2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Modern software systems are increasingly more connected, pervasive, and dynamic, as such, they are subject to more runtime variations than legacy systems. Runtime variations affect system properties, such as performance and availability. The variations are difficult to anticipate and thus mitigate in the system design.

    Self-adaptive software systems were proposed as a solution to monitor and adapt systems in response to runtime variations. Research has established a vast body of knowledge on engineering self-adaptive systems. However, there is a lack of systematic process support that leverages such engineering knowledge and provides for systematic reuse for self-adaptive systems development. 

    This thesis proposes the Autonomic Software Product Lines (ASPL), which is a strategy for developing self-adaptive software systems with systematic reuse. The strategy exploits the separation of a managed and a managing subsystem and describes three steps that transform and integrate a domain-independent managing system platform into a domain-specific software product line for self-adaptive software systems.

    Applying the ASPL strategy is however not straightforward as it involves challenges related to variability and uncertainty. We analyzed variability and uncertainty to understand their causes and effects. Based on the results, we developed the Autonomic Software Product Lines engineering (ASPLe) methodology, which provides process support for the ASPL strategy. The ASPLe has three processes, 1) ASPL Domain Engineering, 2) Specialization and 3) Integration. Each process maps to one of the steps in the ASPL strategy and defines roles, work-products, activities, and workflows for requirements, design, implementation, and testing. The focus of this thesis is on requirements and design.

    We validate the ASPLe through demonstration and evaluation. We developed three demonstrator product lines using the ASPLe. We also conducted an extensive case study to evaluate key design activities in the ASPLe with experiments, questionnaires, and interviews. The results show a statistically significant increase in quality and reuse levels for self-adaptive software systems designed using the ASPLe compared to current engineering practices.

  • 2.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Andersson, Jesper
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Architectural reasoning for dynamic software product lines2013In: Proceedings of the 17th International Software Product Line Conference co-located workshops, ACM Press, 2013, p. 117-124Conference paper (Refereed)
    Abstract [en]

    Software quality is critical in today's software systems. A challenge is the trade-off situation architects face in the design process. Designers often have two or more alternatives, which must be compared and put into context before a decision is made. The challenge becomes even more complex for dynamic software product lines, where domain designers have to take runtime variations into consideration as well. To address the problem we propose extensions to an architectural reasoning framework with constructs/artifacts to define and model a domain's scope and dynamic variability. The extended reasoning framework encapsulates knowledge to understand and reason about domain quality behavior and self-adaptation as a primary variability mechanism. The framework is demonstrated for a self-configuration property, self-upgradability on an educational product-line.

  • 3.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Computer Science.
    Andersson, Jesper
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Computer Science.
    Architectural Reasoning Support for Product-Lines of Self-adaptive Software Systems: A Case Study2015In: Software Architecture: 9th European Conference, ECSA 2015, Dubrovnik/Cavtat, Croatia, September 7-11, 201 / [ed] Danny Weyns, Raffaela Mirandola, Ivica Crnkovic, Springer, 2015, p. 20-36Conference paper (Refereed)
    Abstract [en]

    Software architecture serves as a foundation for the design and development of software systems. Designing an architecture requires extensive analysis and reasoning. The study presented herein focuses on the architectural analysis and reasoning in support of engineering self-adaptive software systems with systematic reuse. Designing self-adaptive software systems with systematic reuse introduces variability along three dimensions; adding more complexity to the architectural analysis and reasoning process. To this end, the study presents an extended Architectural Reasoning Framework with dedicated reasoning support for self-adaptive systems and reuse. To evaluate the proposed framework, we conducted an initial feasibility case study, which concludes that the proposed framework assists the domain architects to increase reusability, reduce fault density, and eliminate differences in skills and experiences among architects, which were our research goals and are decisive factors for a system's overall quality.

  • 4.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Computer Science.
    Andersson, Jesper
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Computer Science.
    ASPLe: a methodology to develop self-adaptive software systems with reuse2017Report (Other academic)
    Abstract [en]

    Advances in computing technologies are pushing software systems and their operating environments to become more dynamic and complex. The growing complexity of software systems coupled with uncertainties induced by runtime variations leads to challenges in software analysis and design. Self-Adaptive Software Systems (SASS) have been proposed as a solution to address design time complexity and uncertainty by adapting software systems at runtime. A vast body of knowledge on engineering self-adaptive software systems has been established. However, to the best of our knowledge, no or little work has considered systematic reuse of this knowledge. To that end, this study contributes an Autonomic Software Product Lines engineering (ASPLe) methodology. The ASPLe is based on a multi-product lines strategy which leverages systematic reuse through separation of application and adaptation logic. It provides developers with repeatable process support to design and develop self-adaptive software systems with reuse across several application domains. The methodology is composed of three core processes, and each process is organized for requirements, design, implementation, and testing activities. To exemplify and demonstrate the use of the ASPLe methodology, three application domains are used as running examples throughout the report.

  • 5.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Andersson, Jesper
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Harnessing Variability in Product-lines of Self-adaptive Software Systems2015In: Proceedings of the 19th International Conference on Software Product Line: SPLC '15, ACM Press, 2015, p. 191-200Conference paper (Refereed)
    Abstract [en]

    This work studies systematic reuse in the context of self-adaptive software systems. In our work, we realized that managing variability for such platforms is different compared to traditional platforms, primarily due to the run-time variability and system uncertainties. Motivated by the fact that recent trends show that self-adaptation will be used more often in future system generation and that software reuse state-of-practice or research do not provide sufficient support, we have investigated the problems and possibly resolutions in this context. We have analyzed variability for these systems, using a systematic reuse prism, and identified a research gap in variability management. The analysis divides variability handling into four activities: (1) identify variability, (2) constrain variability, (3) implement variability, and (4) manage variability. Based on the findings we envision a reuse framework for the specific domain and present an example framework that addresses some of the identified challenges. We argue that it provides basic support for engineering self-adaptive software systems with systematic reuse. We discuss some important avenues of research for achieving the vision.

  • 6.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Andersson, Jesper
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Iftikhar, Muhammad Usman
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Weyns, Danny
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Rigorous architectural reasoning for self-adaptive software systems2016In: Proceedings: First Workshop on Qualitative Reasoning abut Software Architectures, QRASA 2016 / [ed] Lisa O'Conner, IEEE, 2016, p. 11-18Conference paper (Refereed)
    Abstract [en]

    Designing a software architecture requires architectural reasoning, i.e., activities that translate requirements to an architecture solution. Architectural reasoning is particularly challenging in the design of product-lines of self-adaptive systems, which involve variability both at development time and runtime. In previous work we developed an extended Architectural Reasoning Framework (eARF) to address this challenge. However, evaluation of the eARF showed that the framework lacked support for rigorous reasoning, ensuring that the design complies to the requirements. In this paper, we introduce an analytical framework that enhances eARF with such support. The framework defines a set of artifacts and a series of activities. Artifacts include templates to specify domain quality attribute scenarios, concrete models, and properties. The activities support architects with transforming requirement scenarios to architecture models that comply to required properties. Our focus in this paper is on architectural reasoning support for a single product instance. We illustrate the benefits of the approach by applying it to an example client-server system, and outline challenges for future work. © 2016 IEEE.

  • 7.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Andersson, Jesper
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Weyns, Danny
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    ASPLe: a methodology to develop self-adaptive software systems with systematic reuseManuscript (preprint) (Other academic)
    Abstract [en]

    More than two decades of research have demonstrated an increasing need for software systems to be self-adaptive. Self-adaptation is required to deal with runtime dynamics which are difficult to predict before deployment. A vast body of knowledge to develop Self-Adaptive Software Systems (SASS) has been established. We, however, discovered a lack of process support to develop self-adaptive systems with reuse. To that end, we propose a domain-engineering based methodology, Autonomic Software Product Lines engineering (ASPLe), which provides step-by-step guidelines for developing families of SASS with systematic reuse. The evaluation results from a case study show positive effects on quality and reuse for self-adaptive systems designed using the ASPLe compared to state-of-the-art engineering practices.

  • 8.
    Abdiju, Kushtrim
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Exploring a New Way of Food Inventory Management in Households Using Modern Technologies to Reduce Food Waste2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Food waste is becoming an increasing threat to the environment and the economy. Estimates indicate that annually, a third of the food produced around the world ends up being wasted. Only one-fourth of that food is enough to take nearly a billion people out of starvation. Food waste is especially higher in more developed countries, including most of the states in the European Union and the USA. Sector-wise, food is being lost from field to fork, with households topping the charts. Overbuying, not knowing what already is in the fridge, unaware of the food until it eventually expires, are among the most common reasons that contribute to the food waste. The potential prevention of such massive waste could significantly reduce the amount of greenhouse gas emissions around the world and help the economy of the households including all the parties involved in food production, distributing and retailing.

    On the other hand, technology has progressed in very rapid steps. The advancement of AI, ML, IoT, and voice-enabled devices has revolutionized many industries and has made us more efficient as human beings. Unfortunately, these advancements haven't yet had any significant impact in assisting families with their food choices and in preventing them from overbuying and throwing food away. Most of the proposed solutions addressing this issue, do not get integrated into everyday life. That is because they require a lot of manual input, rely entirely on mobile phones, do not show immediate results to keep users motivated, and on top of all, for the sole fact that modern lives are quite complex, and although an important issue, food waste is not an everyday cause of concern of an average person.

    This thesis takes into account all of the shortcomings of the previous works and aims to create a more sustainable solution by exploring new ways of food inventory management in the households by automating the process so that users don't have to manually enter the data themselves. The proposed solution consists of a device that should be easily mounted into any fridge and acts as an interface between users and their food inventory. The device contains a bar-code scanner for the item input and a back-end that is capable of recognizing the item and can in return show user-friendly and valuable information such as the approximate price of the item, the approximate due date etc. and notifies users when an item is about to expire so that they can take appropriate actions.

    7 out of 9 participants in the final conceptual design study said they would use this solution in their homes. The rest of the results from the designed test cases indicate a clear excitement and interest in participants and a willingness to see the prototype in the finished state, all the comments and insights together with the future work and how the feedback will be used into the next iteration are part of the final discussion of this thesis.

  • 9.
    Achilleos, Achilleas
    et al.
    Frederick University, Cyprus.
    Mettouris, Christos
    University of Cyprus, Cyprus.
    Yeratziotis, Alexandros
    University of Cyprus, Cyprus.
    Papadopoulos, George
    University of Cyprus, Cyprus.
    Pllana, Sabri
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Huber, Florian
    SYNYO GmbH, Austria.
    Jäger, Bernhard
    SYNYO GmbH, Austria.
    Leitner, Peter
    SYNYO GmbH, Austria.
    Ocsovszky, Zsófia
    BioTalentum Ltd, Hungary.
    Dinnyés, András
    BioTalentum Ltd, Hungary.
    SciChallenge: A Social Media Aware Platform for Contest-Based STEM Education and Motivation of Young Students2019In: IEEE Transactions on Learning Technologies, ISSN 1939-1382, E-ISSN 1939-1382, Vol. 12, no 1, p. 98-111Article in journal (Refereed)
    Abstract [en]

    Scientific and technological innovations have become increasingly important as we face the benefits and challenges of both globalization and a knowledge-based economy. Still, enrolment rates in STEM degrees are low in many European countries and consequently there is a lack of adequately educated workforce in industries. We believe that this can be mainly attributed to pedagogical issues, such as the lack of engaging hands-on activities utilized for science and math education in middle and high schools. In this paper, we report our work in the SciChallenge European project, which aims at increasing the interest of pre-university students in STEM disciplines, through its distinguishing feature, the systematic use of social media for providing and evaluation of the student-generated content. A social media-aware contest and platform were thus developed and tested in a pan-European contest that attracted >700 participants. The statistical analysis and results revealed that the platform and contest positively influenced participants STEM learning and motivation, while only the gender factor for the younger study group appeared to affect the outcomes (confidence level – p<.05).

  • 10.
    Ahmedi, Figene
    et al.
    University of Prishtina, Serbia.
    Ahmedi, Lule
    University of Prishtina, Serbia.
    O'Flynn, Brendan
    Tyndall National Institute, Ireland;University College Cork, Ireland.
    Kurti, Arianit
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Tahirsylaj, Sylë
    Hydrometeorological Institute of Kosova, Serbia.
    Bytyçi, Eliot
    University of Prishtina, Serbia.
    Sejdiu, Besmir
    University of Prishtina, Serbia.
    Salihu, Astrit
    University of Prishtina, Serbia.
    InWaterSense: An Intelligent Wireless Sensor Network for Monitoring Surface Water Quality to a River in Kosovo2018In: International Journal of Agricultural and Environmental Information Systems, ISSN 1947-3192, Vol. 9, no 1, p. 39-61Article in journal (Refereed)
    Abstract [en]

    A shift in water monitoring approach from traditional grab sampling to novel wireless sensors is gaining in popularity not only among researchers but also in the market. These latest technologies readily enable numerous advantageous monitoring arrangements like remote, continuous, real-time, and spatially-dense and broad in coverage measurements, and identification of long-term trends of parameters of interest. Thus, a WSN system is implemented in a river in Kosovo as part of the InWaterSense project to monitor its water quality parameters. It is one of the first state of the art technology demonstration systems of its kind in the domain of water monitoring in developing countries like Kosovo. Water quality datasets are transmitted at pre-programmed intervals from sensing stations deployed in the river to the server at university via the GPRS network. Data is then made available through a portal to different target groups (policy-makers, water experts, and citizens). Moreover, the InWaterSense system behaves intelligently like staying in line with water quality regulatory standards.

  • 11.
    AL Jorani, Salam
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Performance assessment of Apache Spark applications2019Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    This thesis addresses the challenges of large software and data-intensive systems. We will discuss a Big Data software that consists of quite a bit of Linux configuration, some Scala coding and a set of frameworks that work together to achieve the smooth performance of the system. Moreover, the thesis focuses on the Apache Spark framework and the challenging of measuring the lazy evaluation of the transformation operations of Spark. Investigating the challenges are essential for the performance engineers to increase their ability to study how the system behaves and take decisions in early design iteration. Thus, we made some experiments and measurements to achieve this goal. In addition to that, and after analyzing the result we could create a formula that will be useful for the engineers to predict the performance of the system in production.

  • 12.
    Aleksikj, Stefan
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Visualization of Quantified Self data from Spotify using avatars2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The increased interest for self-tracking through the use of technology has given birth to the Quantified Self movement. The movement empowers users to gain self-knowledge from their own data. The overall idea is fairly recent and as such it provides a vast space for exploration and research. This project contributes to the Quantified self movement by proposing a concept for visualization of personal data using an avatar. The overall work finds inspiration in Chernoff faces visualization and it uses parts of the presentation method within the project design.  

    This thesis presents a visualization approach for Quantified Self data using avatars. It tests the proposed concept through a user study with two iterations. The manuscript holds a detailed overview of the designing process, questionnaire for the data mapping, implementation of the avatars, two user studies and the analysis of the results. The avatars are evaluated using Spotify data. The implementation offers a visualization library that can be reused outside of the scope of this thesis.

    The project managed to deliver an avatar that presents personal data through the use of facial expressions. The results show that the users can understand the proposed mapping of data. Some of the users were not able to gain meaningful insights from the overall use of the avatar, but the study gives directions for further improvements of the concept. 

  • 13.
    Algabroun, Hatem
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Iftikhar, Muhammad Usman
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Weyns, Danny
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Maintenance 4.0 Framework using Self: Adaptive Software Architecture2018In: Journal of Maintenance Engineering, Vol. 2, p. 280-293Article in journal (Refereed)
    Abstract [en]

    With the recent advances of manufacturing technologies, referred to as Industry 4.0, maintenance approaches have to be developed to fulfill the new de-mands. The technological complexity associated to Industry 4.0 makes designing maintenance solutions particularly challenging. This paper proposes a novel maintenance framework leveraging principles from self-adaptation and software architecture. The framework was tested in an operational scenario where a bearing condition in an electrical motor needs to be managed, the results showed a proper operation. As a conclusion, the proposed framework could be used to develop maintenance systems for Industry 4.0.

  • 14.
    Algabroun, Hatem
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Iftikhar, Muhammad Usman
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Weyns, Danny
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM). Catholic University of Leuven, Belgium.
    Maintenance 4.0 Framework Using Self-Adaptive Software Architecture2017In: Proceedings of 2nd International Conference on Maintenance Engineering, IncoME-II 2017.The University of Manchester, UK, The University of Manchester, UK , 2017, , p. 299-309Conference paper (Refereed)
    Abstract [en]

    With the recent advances of manufacturing technologies, referred to as Industry 4.0, maintenance approaches have to be developed to fulfill the new de-mands. The technological complexity associated to Industry 4.0 makes designing maintenance solutions particularly challenging. This paper proposes a novel maintenance framework leveraging principles from self-adaptation and software architecture. The framework was tested in an operational scenario where a bearing condition in an electrical motor needs to be managed, the results showed a proper operation. As a conclusion, the proposed framework could be used to develop maintenance systems for Industry 4.0.

  • 15.
    Alissandrakis, Aris
    et al.
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Media Technology.
    Reski, Nico
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Media Technology.
    Using Mobile Augmented Reality to Facilitate Public Engagement2017In: Extended Papers of the International Symposium on Digital Humanities (DH 2016) / [ed] Koraljka Golub, Marcelo Milrad, CEUR-WS , 2017, Vol. 2021, p. 99-109Conference paper (Refereed)
    Abstract [en]

    This paper presents our initial efforts towards the development of a framework for facilitating public engagement through the use of mobile Augmented Reality (mAR), that fall under the overall project title "Augmented Reality for Public Engagement" (PEAR). We present the concept, implementation, and discuss the results from the deployment of a mobile phone app (PEAR 4 VXO). The mobile app was used for a user study in conjunction with a campaign carried out by Växjö municipality (Sweden) while exploring how to get citizens more engaged in urban planning actions and decisions. These particular activities took place during spring 2016.One of the salient features of our approach is that it combines novel ways of using mAR together with social media, online databases, and sensors, to support public engagement. In addition, the data collection process and audience engagement were tested in a follow-up limited deployment.The analysis and outcomes of our initial results validate the overall concept and indicate the potential usefulness of the app as a tool, but also highlight the need for an active campaign from the part of the stakeholders.Our future efforts will focus on addressing some of the problems and challenges that we have identified during the different phases of this user study.

  • 16.
    Alissandrakis, Aris
    et al.
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Reski, Nico
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Laitinen, Mikko
    University of Eastern Finland, Finland.
    Tyrkkö, Jukka
    Linnaeus University, Faculty of Arts and Humanities, Department of Languages.
    Levin, Magnus
    Linnaeus University, Faculty of Arts and Humanities, Department of Languages.
    Lundberg, Jonas
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Visualizing dynamic text corpora using Virtual Reality2018In: ICAME 39 : Tampere, 30 May – 3 June, 2018: Corpus Linguistics and Changing Society : Book of Abstracts, Tampere: University of Tampere , 2018, p. 205-205Conference paper (Refereed)
    Abstract [en]

    In recent years, data visualization has become a major area in Digital Humanities research, and the same holds true also in linguistics. The rapidly increasing size of corpora, the emergence of dynamic real-time streams, and the availability of complex and enriched metadata have made it increasingly important to facilitate new and innovative approaches to presenting and exploring primary data. This demonstration showcases the uses of Virtual Reality (VR) in the visualization of geospatial linguistic data using data from the Nordic Tweet Stream (NTS) project (see Laitinen et al 2017). The NTS data for this demonstration comprises a full year of geotagged tweets (12,443,696 tweets from 273,648 user accounts) posted within the Nordic region (Denmark, Finland, Iceland, Norway, and Sweden). The dataset includes over 50 metadata parameters in addition to the tweets themselves.

    We demonstrate the potential of using VR to efficiently find meaningful patterns in vast streams of data. The VR environment allows an easy overview of any of the features (textual or metadata) in a text corpus. Our focus will be on the language identification data, which provides a previously unexplored perspective into the use of English and other non-indigenous languages in the Nordic countries alongside the native languages of the region.

    Our VR prototype utilizes the HTC Vive headset for a room-scale VR scenario, and it is being developed using the Unity3D game development engine. Each node in the VR space is displayed as a stacked cuboid, the equivalent of a bar chart in a three-dimensional space, summarizing all tweets at one geographic location for a given point in time (see: https://tinyurl.com/nts-vr). Each stacked cuboid represents information of the three most frequently used languages, appropriately color coded, enabling the user to get an overview of the language distribution at each location. The VR prototype further encourages users to move between different locations and inspect points of interest in more detail (overall location-related information, a detailed list of all languages detected, the most frequently used hashtags). An underlying map outlines country borders and facilitates orientation. In addition to spatial movement through the Nordic areas, the VR system provides an interface to explore the Twitter data based on time (days, weeks, months, or time of predefined special events), which enables users to explore data over time (see: https://tinyurl.com/nts-vr-time).

    In addition to demonstrating how the VR methods aid data visualization and exploration, we will also briefly discuss the pedagogical implications of using VR to showcase linguistic diversity.

  • 17.
    Alsouda, Yasser
    et al.
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Pllana, Sabri
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Kurti, Arianit
    RISE Interactive, Sweden.
    A Machine Learning Driven IoT Solution for Noise Classification in Smart Cities2018In: Machine Learning Driven Technologies and Architectures for Intelligent Internet of Things (ML-IoT), August 28, 2018, Prague, Czech Republic, Euromicro , 2018, p. 1-6Conference paper (Refereed)
    Abstract [en]

    We present a machine learning based method for noise classification using a low-power and inexpensive IoT unit. We use Mel-frequency cepstral coefficients for audio feature extraction and supervised classification algorithms (that is, support vector machine and k-nearest neighbors) for noise classification. We evaluate our approach experimentally with a dataset of about 3000 sound samples grouped in eight sound classes (such as, car horn, jackhammer, or street music). We explore the parameter space of support vector machine and k-nearest neighbors algorithms to estimate the optimal parameter values for classification of sound samples in the dataset under study. We achieve a noise classification accuracy in the range 85% -- 100%. Training and testing of our k-nearest neighbors (k = 1) implementation on Raspberry Pi Zero W is less than a second for a dataset with features of more than 3000 sound samples.

  • 18.
    Alsouda, Yasser
    et al.
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Pllana, Sabri
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Kurti, Arianit
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    IoT-based Urban Noise Identification Using Machine Learning: Performance of SVM, KNN, Bagging, and Random Forest2019In: Proceedings of the International Conference on Omni-Layer Intelligent Systems (COINS '19), New York: ACM Publications, 2019, p. 62-67Conference paper (Refereed)
    Abstract [en]

    Noise is any undesired environmental sound. A sound at the same dB level may be perceived as annoying noise or as pleasant music. Therefore, it is necessary to go beyond the state-of-the-art approaches that measure only the dB level and also identify the type of noise. In this paper, we present a machine learning based method for urban noise identification using an inexpensive IoT unit. We use Mel-frequency cepstral coefficients for audio feature extraction and supervised classification algorithms (that is, support vector machine, k-nearest neighbors, bootstrap aggregation, and random forest) for noise classification. We evaluate our approach experimentally with a data-set of about 3000 sound samples grouped in eight sound classes (such as car horn, jackhammer, or street music). We explore the parameter space of the four algorithms to estimate the optimal parameter values for classification of sound samples in the data-set under study. We achieve a noise classification accuracy in the range 88% - 94%.

  • 19.
    Alvarez, Claudio
    et al.
    Universidad de Los Andes.
    Salavati, Sadaf
    Linnaeus University, Faculty of Technology, Department of Informatics.
    Nussbaum, Miguel
    Pontificia Universidad Catolica de Chile.
    Milrad, Marcelo
    Linnaeus University, Faculty of Technology, Department of Media Technology.
    Collboard: Fostering new media literacies in the classroom through collaborative problem solving supported by digital pens and interactive whiteboards2013In: Computers and education, ISSN 0360-1315, E-ISSN 1873-782X, Vol. 63, p. 368-379Article in journal (Refereed)
    Abstract [en]

    Education systems worldwide must strive to support the teaching of a set of New Media Literacies (NMLs). These literacies respond to the need for educating human capital within participatory cultures in a highly technologized world. In this paper, we present Collboard, a constructivist problem solving activity for fostering the development of specific NMLs in classrooms: collective intelligence, distributed cognition and transmedia navigation. Collboard encompasses successive individual and collaborative work phases that prompt active student participation and engagement. It integrates digitally augmented appliances, namely, digital pens as a means to support individual work, and interactive whiteboards as a collaborative knowledge construction space. We report on the conceptual design of Collboard, its different technological and software components, as well as our findings from experiences we conducted in a Swedish school with 12 students from a 7th grade maths class. Findings from the experience provide an indication that Collboard can be well integrated in classroom teaching, and that it can foster the development of collective intelligence, distributed cognition and transmedia navigation in different knowledge domains. (C) 2013 Elsevier Ltd. All rights reserved.

  • 20.
    Amatya, Suyesh
    et al.
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Computer Science.
    Kurti, Arianit
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Computer Science.
    Cross-Platform Mobile Development: Challenges and Opportunities2013In: ICT Innovations 2013: ICT Innovations and Education / [ed] Vladimir Trajkovik and Misev Anastas, Springer, 2013, 1, p. 219-229Chapter in book (Refereed)
    Abstract [en]

    Mobile devices and mobile computing have made tremendous advances and become ubiquitous in the last few years. As a result, the landscape has become seriously fragmented which brings lots of challenges for the mobile development process. Whilst native approach of mobile development still is the predominant way to develop for a particular mobile platform, recently there is shifting towards cross-platform mobile development as well. In this paper, we have performed a survey of the literature to see the trends in cross-platform mobile development over the last few years. With the result of the survey, we argue that the web-based approach and in particular,hybrid approach, of mobile development serves the best for cross-platform development. The results of this work indicate that even though cross platform tools are not fully matured they show great potential. Thus we consider that cross-platform development offers great opportunities for rapid development of high-fidelity prototypes of the mobile application.

  • 21.
    Ambrosius, Robin
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Machine Learning Based Optimizations for Bot Aided Interviews: In the Field of Due Diligence2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Startups need investments in order to scale their business. The value of such startups, especially software-based startups, are difficult to evaluate because there is no physical value that can be judged.  The company DueDive built experience in due diligence by conducting many interviews in this area, which are the base for the due diligence. These interviews are time consuming and require a lot of domain knowledge in the field, which makes them very expensive. This thesis evaluated different machine learning algorithms to integrate into a software that supports such interviews process. The goal is to shorten the interview duration and lowering the required know know for the interviewer using suggestions by the AI. The software uses completed interview sessions to provide enhanced suggestions through artificial intelligence. The proposed solution uses basket analysis and imputation to analyze the collected data. The result is a topic-independent software that is used to administrate and carry out interviews with the help of AI. The results are validated and evaluated in a case study using a generic, self-defined interview.

  • 22.
    Ambrosius, Robin
    et al.
    Dezember IT GmbH, Germany.
    Ericsson, Morgan
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Löwe, Welf
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Wingkvist, Anna
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Interviews Aided with Machine Learning2018In: Perspectives in Business Informatics Research. BIR 2018: 17th International Conference, BIR 2018, Stockholm, Sweden, September 24-26, 2018, Proceedings / [ed] Zdravkovic J., Grabis J., Nurcan S., Stirna J., Springer, 2018, Vol. 330, p. 202-216Conference paper (Refereed)
    Abstract [en]

    We have designed and implemented a Computer Aided Personal Interview (CAPI) system that learns from expert interviews and can support less experienced interviewers by for example suggesting questions to ask or skip. We were particularly interested to streamline the due diligence process when estimating the value for software startups. For our design we evaluated some machine learning algorithms and their trade-offs, and in a small case study we evaluates their implementation and performance. We find that while there is room for improvement, the system can learn and recommend questions. The CAPI system can in principle be applied to any domain in which long interview sessions should be shortened without sacrificing the quality of the assessment.

  • 23.
    Andersson, Jesper
    et al.
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Caporuscio, Mauro
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Aligning Architectures for Sustainability2016In: ACM Proccedings of the 10th European Conference on Software Architecture Workshops (ECSA-W) / [ed] Rami Bahsoon and Rainer Weinreich, ACM Press, 2016, article id 13Conference paper (Refereed)
    Abstract [en]

    The digitization of industry has drastically changed the competitive landscape by requiring a higher degree of specialization and shorter time to delivery that affect the design properties a software platform should satisfy. The platform architecture must sustain continuous and rapid change to the organizational architecture, which in turn is affected by external forces: i.e., forces drive the velocity of change. In this paper, we explore the effects of digitization, characterizing internal and external forces that impact on business strategies and trigger the continuous realignment of the platform, and outline a research agenda to mitigate the effects.

  • 24.
    Andersson, Rikard
    et al.
    Chalmers University of Technology.
    Ericsson, Morgan
    University of Gothenburg.
    Wingkvist, Anna
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Computer Science.
    Mining Relations from Git Commit Messages: an Experience Report2014In: Proceedings of the Fifth Swedish Language Technology Conference, 2014Conference paper (Refereed)
  • 25.
    Andras, Balla
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    A comparison between serverless and Docker container deployments: In the cloud2018Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    Designing an application from top to bottom is a challenge for any software architect. Designing an application to be deployed in the cloud adds extra complexity and a variety of questions to the task. One of these questions is how to deploy an application? The most popular choices at this time are either Docker containers or serverless functions. This report presents a comparison between the two deployment methods based on cost and performance. The comparison did not yield a conclusive winner but it did offer some key pointers to help with the decision. Docker containers offer a standardized deployment method for a low price and with good performance. Before choosing Docker the intended market needs to be evaluated given that for each region Docker needs to serve, the price also increases. Serverless functions offer auto-scaling and easy global deployments but suffer from high complexity, slower performance, and an uncertain monthly price tag.

  • 26.
    Arhammar Andersson, Molly
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Tillgänglighet, testning och förtroende: eller konsten att inte vara ett funktionshinder2018Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [sv]

    Arbetet undersöker hur Sveriges kommuner valt att testa tillgänglighetsanpassningen av sina webbplatser och vilket förtroende de har för att webbplatsen är tillgänglighetsanpassad. Dessa två faktorer analyseras sedan i relation till varandra för att belysa om, och i så fall på vilket sätt, testpraktik påverkar förtroende. Resultatet ställs i kontrast mot den tidigare forskning som säger att manuell testning av tillgänglighetsanpassning är mer pålitlig än automatisk sådan, samt att testning överlag leder till högre förtroende. Undersökningen görs genom en enkätundersökning utskickad till alla Sveriges kommuner och kommer fram till att det, i samklang med tidigare forskning, går att se att närvaro av testning leder till högre förtroende, medan det i motsats till vad forskningen indikerar inte går att se att de som testar manuellt har ett generellt högre förtroende än de som testar automatiskt. Detta leder till slutsatsen om att datavetenskapen måste kommunicera ut sin kunskap om hur testning av tillgänglighetsanpassning kan utföras på bästa sätt, att kommunerna själva behöver få tillgång till mer kunskap om hur man testar effektivt och pålitligt med manuell testning, och pekar mot vidare forskning inom datavetenskap, filosofi och psykologi kring testning, förtroende och människans relation till maskinen.

  • 27.
    Arhammar Andersson, Molly
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    What we talk about when we talk about winners: Using clustering of Twitter topics as a basis for election prediction2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Social media has over the years partly become a platform to express opinions and discuss current events. Within the field of Computer Science, Twitter has been used both as the basis for political analysis - for example using sentiment analysis to predict election results - and within the field of cluster analysis, where the question of how to best design and use an algorithm to extract topics from tweets has been studied. The ClusTop algorithm is specifically designed to cluster tweets based on topics. This paper aims to explore whether it is possible to (a) use an implementation of the ClusTop algorithm to identify topics connected to tweets about Trump and Clinton just before the American 2016 election, and (b) distinguish between the topics used in connection with a specific candidate in states where they won versus states where they lost the election. The problem is approached through the method of a controlled experiment where the data collected from Twitter is divided into groups and run through the ClusTop algorithm. The topics are then compared to draw tentative conclusions about their validity as a basis for election prediction. The study finds that it is indeed possible to adapt the ClusTop algorithm to use with tweets and geolocation to identify different topics, thus confirming the usefulness of the algorithm. In addition to this, the study confirms that manually examining the words used within the topics makes it possible to see differences between them. The work thereby places itself in the tradition of exploring how Twitter can be used for election prediction by being one of the first studies to look at clustering as a way of approaching the problem.

  • 28.
    Artac, Matej
    et al.
    XLAB, Slovenia.
    Borovsak, Tadej
    XLAB, Slovenia.
    Di Nitto, Elisabetta
    The Polytechnic University of Milan, Italy.
    Guerriero, Michele
    The Polytechnic University of Milan, Italy.
    Perez-Palacin, Diego
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Tamburri, Damian Andrew
    The Polytechnic University of Milan, Italy.
    Infrastructure-as-code for data-intensive architectures: a model-driven development approach2018In: 2018 IEEE 25th International Conference on Software Architecture (ICSA), IEEE, 2018, p. 156-165Conference paper (Refereed)
    Abstract [en]

    As part of the DevOps tactics, Infrastructure-as- Code (IaC) provides the ability to create, configure, and manage complex infrastructures by means of executable code. Writing IaC, however, is not an easy task, since it requires blending different infrastructure programming languages and abstractions, each specialized on a particular aspect of infrastructure creation, configuration, and management. Moreover, the more the architectures become large and complex (e.g. Data-Intensive or Microservice-based architectures), the more dire the need of IaC becomes. The goal of this paper is to exploit Model- Driven Engineering (MDE) to create language-agnostic models that are then automatically transformed into IaC. We focus on the domain of Data-Intensive Applications as these typically exploit complex infrastructures which demand sophisticated and fine-grained configuration and re-configuration — we show that, through our approach, called DICER, it is possible to create complex IaC with significant amounts of time savings, both in IaC design as well as deployment and re-deployment times.

  • 29.
    Aspernäs, Andreas
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Human-like Crawling for Humanoid Robots: Gait Evaluation on the NAO robot2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Human-robot interaction (HRI) is the study of how we as humans interact and communicate with robots and one of its subfields is working on how we can improve the collaboration between humans and robots. We need robots that are more user friendly and easier to understand and a key aspect of this is human-like movements and behavior. This project targets a specific set of motions called locomotion and tests them on the humanoid NAO robot. A human-like crawling gait was developed for the NAO robot and compared to the built-in walking gait through three kinds of experiments. The first one to compare the speed of the two gaits, the second one to estimate their sta- bility, and the third to examine how long they can operate by measuring the power consumption and temperatures in the joints. The results showed the robot was significantly slower when crawling compared to walking, and when still the robot was more stable while standing than on all-fours. The power consumption remained essentially the same, but the crawling gait ended up having a shorter operational time due to higher temperature increase in the joints. While the crawling gait has benefits of having a lower profile then the walking gait and could therefore more easily pass under low hanging obsta- cles, it does have major issues that needs to be addressed to become a viable solution. Therefore these are important factors to consider when developing gaits and designing robots, and motives further research to try and solve these problems.

  • 30.
    Axelsson, Jakob
    et al.
    Swedish Inst Comp Sci, Kista, Sweden ; Mälardalen Univ.
    Papatheocharous, Efi
    Swedish Inst Comp Sci, Kista.
    Andersson, Jesper
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Characteristics of software ecosystems for Federated Embedded Systems: A case study2014In: Information and Software Technology, ISSN 0950-5849, E-ISSN 1873-6025, Vol. 56, no 11, p. 1457-1475Article in journal (Refereed)
    Abstract [en]

    Context: Traditionally, Embedded Systems (ES) are tightly linked to physical products, and closed both for communication to the surrounding world and to additions or modifications by third parties. New technical solutions are however emerging that allow addition of plug-in software, as well as external communication for both software installation and data exchange. These mechanisms in combination will allow for the construction of Federated Embedded Systems (FES). Expected benefits include the possibility of third-party actors developing add-on functionality; a shorter time to market for new functions; and the ability to upgrade existing products in the field. This will however require not only new technical solutions, but also a transformation of the software ecosystems for ES. Objective: This paper aims at providing an initial characterization of the mechanisms that need to be present to make a FES ecosystem successful. This includes identification of the actors, the possible business models, the effects on product development processes, methods and tools, as well as on the product architecture. Method: The research was carried out as an explorative case study based on interviews with 15 senior staff members at 9 companies related to ES that represent different roles in a future ecosystem for FES. The interview data was analyzed and the findings were mapped according to the Business Model Canvas (BMC). Results: The findings from the study describe the main characteristics of a FES ecosystem, and identify the challenges for future research and practice. Conclusions: The case study indicates that new actors exist in the FES ecosystem compared to a traditional supply chain, and that their roles and relations are redefined. The business models include new revenue streams and services, but also create the need for trade-offs between, e.g., openness and dependability in the architecture, as well as new ways of working. (C) 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.orgilicensesiby/3.0/).

  • 31.
    Azimimusolo, Tahereh
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Media Technology.
    Touch Features in Advancing Children's Learning2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    When examining the boundaries and issues imposed by the traditional ways of learning, questions about the role that new technologies can play in eliminating these boundaries easily emerge. This thesis intends to shed light onto these issues and better understand the effectiveness of using new technologies to overcome pupils’ problems in learning mathematics.

    The empirical study conducted involves investigating how touch features available on tablets can enhance children’s learning. The aim is to study the significance of touch features existing on tablets in helping young pupils learn mathematical concepts like timetables. So, the general question underlying this research is “what functionalities of tablet technologies are effective to enhance children’s learning and what barriers are there to more effective use of them?”

    Although previous research has studied the role of tablets on pupils’ learning, less attention has been directed towards the study of the effect of touch-input functionality in tablets to facilitate children’s learning. This thesis wants to contribute to the topic by analyzing how a particular functionality available, the touch-input functionality, can be utilized to foster learning.

  • 32.
    Azmat, Janty
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Performance Evaluation of Node.js on Multi-core Computing Systems2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Since JavaScript code that is executed by the Node.js run-time environment is run in a single thread without really utilizing the full power of multi-core systems, fairly new approaches attempt to solve this situation. Some of these approaches are considered well publicly tested and are widely used at the time of writing this document. The objectives for this study are to check which ones of these approaches achieve the better scalability in accordance to the number of handled requests, and to what extent those approaches utilize the multi-core power compared to the raw Node.js environment with the normal CPU scheduling.

  • 33.
    Baan, Willem
    et al.
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Computer Science. ASTRON, Netherlands;Shanghai Astron Observ, Peoples Republic of China.
    Loenen, A. F.
    ASTRON, Netherlands;Kapteyn Astron Inst, Netherlands.
    Spaans, M.
    Kapteyn Astron Inst, Netherlands.
    Multimolecular studies of Galactic star-forming regions2014In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 445, no 4, p. 3331-3344Article in journal (Refereed)
    Abstract [en]

    Molecular emission-line observations of isolated Galactic star-forming regions are used to model the physical properties of the molecular interstellar medium in these systems. Observed line ratios are compared with the results predicted by models that incorporate gas-phase chemistry and the heating by stellar radiation and non-radiative feedback processes. The line ratios of characteristic tracer molecules may be interpreted using the contributions of two distinct components: a cold (40-50 K) and high-density (105-105.5 cm(-3)) photon-dominated region (PDR) with a nominal UV flux density and a warm (similar to 300 K) mechanical heating-dominated region (MHDR) with a slightly lower density (10(4.5)-10(5) cm(-3)). The relative contributions of these structural components are used to model the observed line ratios. Ionized species may be better modelled by adopting an increase of the cosmic ray flux towards the Galactic Centre and the sulphur abundance should depleted by a factor of 200-400 relative to solar values. The line ratios of the Galactic sample are found to be very similar to those of the integrated signature of prominent (ultra) luminous IR Galaxies. The PDRs and MHDRs in the isolated Galactic regions may be modelled with slightly higher mean densities than in extragalactic systems and a higher MHDR temperature resulting from non-radiative mechanical heating. Multimolecular studies are effective in determining the physical and chemical properties of star formation regions by using characteristic line ratios to diagnose their environment. The addition of more molecular species will reduce the existing modelling redundancy.

  • 34.
    Bacha, Kirill
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    DevOps compliant guidelines for project inception-elaboration phases2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    DevOps is an ill-defined but trending approach to software development. Many companies are seduced by its promises of reduced costs and risks. DevOps life-cycle is often represented as a continuous everything, but very little is said about how to get the ball rolling. This report examines how DevOps definitions are represented in the initiation of Agile projects. By interviewing developers and mapping their project initiation activities in a DevOps context, a set of guidelines was formed. Continuous Integration and Deployment were found most prominent DevOps attributes from a developer’s perspective. The operational responsibility is skewed toward maintenance, with low interest in further adjustment.

  • 35.
    Bagheri, Maryam
    et al.
    Sharif Univ Technol, Iran.
    Sirjani, Marjan
    Mälardalen University;Reykjavik Univ, Iceland.
    Khamespanah, Ehsan
    Reykjavik Univ, Iceland;Univ Tehran, Iran.
    Khakpour, Narges
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Akkaya, Ilge
    Univ Calif Berkeley, USA.
    Movaghar, Ali
    Sharif Univ Technol, Iran.
    Lee, Edward A.
    Univ Calif Berkeley, USA.
    Coordinated actor model of self-adaptive track-based traffic control systems2018In: Journal of Systems and Software, ISSN 0164-1212, E-ISSN 1873-1228, Vol. 143, p. 116-139Article in journal (Refereed)
    Abstract [en]

    Self-adaptation is a well-known technique to handle growing complexities of software systems, where a system autonomously adapts itself in response to changes in a dynamic and unpredictable environment. With the increasing need for developing self-adaptive systems, providing a model and an implementation platform to facilitate integration of adaptation mechanisms into the systems and assuring their safety and quality is crucial. In this paper, we target Track-based Traffic Control Systems (TTCSs) in which the traffic flows through pre-specified sub-tracks and is coordinated by a traffic controller. We introduce a coordinated actor model to design self-adaptive TTCSs and provide a general mapping between various TTCSs and the coordinated actor model. The coordinated actor model is extended to build large-scale self-adaptive TTCSs in a decentralized setting. We also discuss the benefits of using Ptolemy II as a framework for model-based development of large-scale self-adaptive systems that supports designing multiple hierarchical MAPE-K feedback loops interacting with each other. We propose a template based on the coordinated actor model to design a self-adaptive TTCS in Ptolemy II that can be instantiated for various TTCSs. We enhance the proposed template with a predictive adaptation feature. We illustrate applicability of the coordinated actor model and consequently the proposed template by designing two real-life case studies in the domains of air traffic control systems and railway traffic control systems in Ptolemy II.

  • 36.
    Balegh, Walid
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Communication and Adaptation in a Ubiquitous Environment2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Context awareness means sending the right information to the right user at the righttime. Context is our environment, which can be anything around us such as location,lights, noises etc. To make the context interact with our mobile devices or sensors,there must be protocols for communication and data formats for the “sent” or “received”contextual information so we can give very specific context information tothe user. Since this communication and adaptive part is not well understood, in thispaper we are interested in investigating the technology used for adaptation. We willalso explain how this technology works to adapt itself to changes in the environment.

  • 37.
    Bechmann, Dominique
    et al.
    CNRS-Université de Strasbourg, France.
    Chessa, ManuelaUniversity of Genoa, Italy.Cláudio, Ana-PaulaUniversidade de Lisboa, Portugal.Imai, FranciscoApple Inc., United States .Kerren, AndreasLinnaeus University, Faculty of Technology, Department of computer science and media technology (CM).Richard, PaulUniversity of Angers, France .Telea, Alexandru C.University of Groningen, Netherlands.Tremeau, AlainUniversité Jean Monnet in Saint Etienne, France.
    Computer Vision, Imaging and Computer Graphics - Theory and Applications: International Joint Conference, VISIGRAPP 2018, Funchal-Madeira, Portugal, January 27-29, 2018, Revised Selected Papers2019Collection (editor) (Refereed)
  • 38.
    Beel, Joeran
    et al.
    Docear, Germany.
    Gipp, Bela
    Univ Konstanz, Germany.
    Langer, Stefan
    Otto von Guericke Univ, Germany.
    Breitinger, Corinna
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Media Technology.
    Research-paper recommender systems: a literature survey2016In: International Journal on Digital Libraries, ISSN 1432-5012, E-ISSN 1432-1300, Vol. 17, no 4, p. 305-338Article in journal (Refereed)
    Abstract [en]

    In the last 16 years, more than 200 research articles were published about research-paper recommender systems. We reviewed these articles and present some descriptive statistics in this paper, as well as a discussion about the major advancements and shortcomings and an overview of the most common recommendation concepts and approaches. We found that more than half of the recommendation approaches applied content-based filtering (55 %). Collaborative filtering was applied by only 18% of the reviewed approaches, and graph-based recommendations by 16%. Other recommendation concepts included stereotyping, item-centric recommendations, and hybrid recommendations. The content-based filtering approaches mainly utilized papers that the users had authored, tagged, browsed, or downloaded. TF-IDF was the most frequently applied weighting scheme. In addition to simple terms, n-grams, topics, and citations were utilized to model users' information needs. Our review revealed some shortcomings of the current research. First, it remains unclear which recommendation concepts and approaches are the most promising. For instance, researchers reported different results on the performance of content-based and collaborative filtering. Sometimes content-based filtering performed better than collaborative filtering and sometimes it performed worse. We identified three potential reasons for the ambiguity of the results. (A) Several evaluations had limitations. They were based on strongly pruned datasets, few participants in user studies, or did not use appropriate baselines. (B) Some authors provided little information about their algorithms, which makes it difficult to re-implement the approaches. Consequently, researchers use different implementations of the same recommendations approaches, which might lead to variations in the results. (C) We speculated that minor variations in datasets, algorithms, or user populations inevitably lead to strong variations in the performance of the approaches. Hence, finding the most promising approaches is a challenge. As a second limitation, we noted that many authors neglected to take into account factors other than accuracy, for example overall user satisfaction. In addition, most approaches (81%) neglected the user-modeling process and did not infer information automatically but let users provide keywords, text snippets, or a single paper as input. Information on runtime was provided for 10% of the approaches. Finally, few research papers had an impact on research-paper recommender systems in practice. We also identified a lack of authority and long-term research interest in the field: 73% of the authors published no more than one paper on research-paper recommender systems, and there was little cooperation among different co-author groups. We concluded that several actions could improve the research landscape: developing a common evaluation framework, agreement on the information to include in research papers, a stronger focus on non-accuracy aspects and user modeling, a platform for researchers to exchange information, and an open-source framework that bundles the available recommendation approaches.

  • 39.
    Bengtsson, Emil
    et al.
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Mattsson, Emil
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Smart task logging: Prediction of tasks for timesheets with machine learning2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Every day most people are using applications and services that are utilising machine learning, in some way, without even knowing it. Some of these applications and services could, for example, be Google’s search engine, Netflix’s recommendations, or Spotify’s music tips. For machine learning to work it needs data, and often a large amount of it. Roughly 2,5 quintillion bytes of data are created every day in the modern information society. This huge amount of data can be utilised to make applications and systems smarter and automated. Time logging systems today are usually not smart since users of these systems still must enter data manually. This bachelor thesis will explore the possibility of applying machine learning to task logging systems, to make it smarter and automated. The machine learning algorithm that is used to predict the user’s task, is called multiclass logistic regression, which is categorical. When a small amount of training data was used in the machine learning process the predictions of a task had a success rate of about 91%.

  • 40.
    Benkner, Siegfried
    et al.
    University of Vienna, Austria.
    Pllana, Sabri
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Träff, Jesper
    University of Vienna, Austria.
    Tsigas, Philippas
    Chalmers University of Technology.
    Richards, Andrew
    Codeplay Software Limited, United Kingdom.
    Russell, George
    INRIA, France.
    Thibault, Samuel
    INRIA, France.
    Augonnet, Cedric
    INRIA, France.
    Namyst, Raymond
    INRIA, France.
    Cornelius, Herbert
    Intel Gmbh, France.
    Kessler, Christoph
    Linköping University.
    Moloney, David
    Movidius Ltd, Ireland.
    Sanders, Peter
    KarlsruherInstitut Für Technologie, Germany.
    Peppher: Performance Portability and Programmability for Heterogeneous Many-Core Architectures2017In: Programming multi-core and many-core computing systems / [ed] Sabri Pllana, Fatos Xhafa, John Wiley & Sons, 2017, 1, p. 243-260Chapter in book (Refereed)
    Abstract [en]

    PEPPHER takes a pluralistic and parallelization agnostic approach to programmability and performance portability for heterogeneous many-core architectures. The PEPPHER framework is in principle language independent but focuses on supporting C++ code with PEPPHER-specific annotations as pragmas or external annotations. The framework is open and extensible; the PEPPHER methodology details how new architectures are incorporated. The PEPPHER methodology consists of rules for how to extend the framework for new architectures. This mainly concerns adaptivity and autotuning for algorithm libraries, the necessary hooks and extensions for the run-time system and any supporting algorithms and data structures that this relies on. Offloading is a specific technique for programming heterogeneous platforms that can sometimes be applied with high efficiency. Offload as developed by the PEPPHER partner Codeplay is a particular, nonintrusive C++ extension allowing portable C++ code to support diverse heterogeneous multicore architectures in a single code base.

  • 41.
    Berg, Isabel
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Modernising George – a home automation user interface2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Home automation is growing faster than ever, incenting ever-more capabilities meanwhile users raise their expectations. Several flaws and latencies have been discovered with the user interfaces available for HomeSeer home automation. Thus, George was developed to address these. A combination of issues, mainly high latency, blocking I/O requests and hard coded references led to user abandonment, and instead an entirely new solution was created – based on the same fundamental concept – using modern techniques for superior performance. Humans are constantly seeking ways of easing problems and the home automation market is growing rapidly. Meanwhile, software developers are sharing ever-more reusable modular functionality across the Web. Thus, systems can now be developed relatively quickly as well as maintained and extended continuously. This has allowed George to address the initial issues and provide a usable and high performant solution in its place. George is not yet working at full capacity but satisfies the objectives of the project. Furthermore, suggestions of future work to further address the everyday events of home automation users are discussed. Though the software is only compatible with HomeSeer, its concept and approach may be shared across the fields of software development and user interaction.

  • 42.
    Bernardi, Simona
    et al.
    University of Zaragoza, Spain.
    Domínguez, Juan L.
    Prodevelop SL, Spain.
    Gómez, Abel
    Universitat Oberta de Catalunya, Spain.
    Joubert, Christophe
    Prodevelop SL, Spain.
    Merseguer, Jose
    University of Zaragoza, Spain.
    Perez-Palacin, Diego
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Requeno, José I.
    University of Zaragoza, Spain.
    Romeu, Alberto
    Prodevelop SL, Spain.
    A systematic approach for performance assessment using process mining: An industrial experience report2018In: Journal of Empirical Software Engineering, ISSN 1382-3256, E-ISSN 1573-7616, Vol. 23, no 6, p. 3394-3441Article in journal (Refereed)
    Abstract [en]

    Software performance engineering is a mature field that offers methods to assess system performance. Process mining is a promising research field applied to gain insight on system processes. The interplay of these two fields opens promising applications in the industry. In this work, we report our experience applying a methodology, based on process mining techniques, for the performance assessment of a commercial data-intensive software application. The methodology has successfully assessed the scalability of future versions of this system. Moreover, it has identified bottlenecks components and replication needs for fulfilling business rules. The system, an integrated port operations management system, has been developed by Prodevelop, a medium-sized software enterprise with high expertise in geospatial technologies. The performance assessment has been carried out by a team composed by practitioners and researchers. Finally, the paper offers a deep discussion on the lessons learned during the experience, that will be useful for practitioners to adopt the methodology and for researcher to find new routes.

  • 43.
    Berrevoets, Robbe
    et al.
    Katholieke Univ Leuven, Belgium.
    Weyns, Danny
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM). Katholieke Univ Leuven, Belgium.
    A QoS-aware Adaptive Mobility Handling Approach for LoRa-based IoT Systems2018In: 2018 12TH IEEE International Conference on Self-Adaptive and Self-Organizing Systems (SASO 2018), IEEE, 2018, p. 130-139Conference paper (Refereed)
    Abstract [en]

    Internet-of-Things (IoT) is an emergent paradigm that is increasingly applied in smart cities. A popular technology used in IoT is LoRa that supports long-range wireless communication. In this research, we study LoRa-based IoT systems with battery-powered end nodes that collect and communicate data to a gateway for further processing. Existing approaches in such IoT systems usually only consider stationary end nodes. We focus on systems with mobile end nodes, paving the way to new applications such as target tracking. Key Quality of Service (QoS) requirements for these settings are the reliability of the communication and energy consumption. With mobile end nodes, ensuring these QoS is challenging as the system is subject to continuous changes. In this paper, we investigate how the settings of a mobile end node impact key performance indicators for reliability and energy consumption. Based on insights obtained from extensive field experiments, we devise an algorithm that automatically adapts the settings of a mobile end node to ensure its QoS requirements for a setup with a single gateway. We then extend the algorithm to a setup with multiple gateways. We demonstrate how the algorithms achieve the QoS requirements of a mobile end node in a concrete IoT deployment.

  • 44.
    Biedl, Therese
    et al.
    University of Waterloo, Canada.
    Kerren, AndreasLinnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Graph Drawing and Network Visualization: 26th International Symposium, GD 2018, Barcelona, Spain, September 26-28, 2018, Proceedings2018Conference proceedings (editor) (Refereed)
    Abstract [en]

    This book constitutes the refereed proceedings of the 26th International Symposium on Graph Drawing and Network Visualization, GD 2018, held in Barcelona, Spain, in September 2018. 

    The 41 full papers presented in this volume were carefully reviewed and selected from 85 submissions. They were organized in topical sections named: planarity variants; upward drawings; RAC drawings; orders; crossings; crossing angles; contact representations; specialized graphs and trees; partially fixed drawings, experiments; orthogonal drawings; realizability; and miscellaneous. The book also contains one invited talk in full paper length and the Graph Drawing contest report.

  • 45.
    Björkskog, Gaston
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Detecting cheaters who utilise third-party software to gain an advantage in multiplayer video games2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Playing video games are meant to be a fun experience but something that has been proven to ruin the experience are cheaters, maybe even more so in events such as tournaments where money is involved. Even if anti-cheating software exists there also exists a research gap in the subject of cheat detection. And regarding cheat detection the question that matters the most is: how do you even detect a player that is using 3rd-party software to gain an unfair advantage in online video games? To find a solution for this problem a systematic literature review was made were data was extracted from articles relevant for the subject and summarised into results. From the results, a few elementary concepts regarding cheat detection are introduced and analysed with comparisons to the problem statement. Finally, five different types of cheat detection are shown that work by analysing objects such as behaviour, game state or memory.

  • 46.
    Björn, Hedin
    et al.
    KTH Royal Institute of Technology.
    Zapico, Jorge Luis
    Linnaeus University, Faculty of Technology, Department of Media Technology.
    Kilowh.at – Increasing Energy Awareness Using an Interactive Energy Comparison Tool2017In: Persuasive Technology: Development and Implementation of Personalized Technologies to Change Attitudes and Behaviors / [ed] de Vries, P.W., Oinas-Kukkonen, H., Siemons, L., Beerlage-de Jong, N., van Gemert-Pijnen, L, Springer, 2017, p. 175-185Conference paper (Refereed)
    Abstract [en]

    Reducing the use of energy is important for several reasons, such as saving money and reducing impact on the climate. However, the awareness among non-experts of how much energy is required by different activities is generally low, which can lead to wrong prioritizations. In this study, we have developed an interactive tool to increase “energy awareness”. A group of 58 students first did a test to benchmark their current energy awareness, then tried the tool for 10 min, and then did the same test immediately after trying the prototype and one week after trying the prototype. In addition, they answered questions regarding which, if any, of the energy requirement of different activities surprised them, any thoughts about their own energy use aroused after using the prototype and what they thought about using the tool compared to more conventional methods of learning. The results showed a significant learning effect in energy awareness with a very strong effect size of 1.689, that they were most surprised by the energy required to produce a hamburger, 39 of 58 explicitly said they intended to change one or more aspects in order to improve their energy use, where 24 actions involved changing habits and 18 actions was of a one-time investment character. The attitude towards using such a tool instead of more conventional learning was very good and the words most frequently used to describe the tool was good, simple and easy to use, fun, and interesting, but five users also said they were bored after a while. In total the results indicate that using an interactive tool like this even for a limited time is a good way to in an efficient and fun way increase energy awareness.

  • 47.
    Björn, Hedin
    et al.
    KTH Royal Institute of Technology.
    Zapico, Jorge Luis
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    What Can You Do with 100 kWh?: A Longitudinal Study of Using an Interactive Energy Comparison Tool to Increase Energy Awareness2018In: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 10, no 7, article id 2269Article in journal (Refereed)
    Abstract [en]

    Reducing the use of energy is important for several reasons, such as saving money and reducing impact on the climate. However, the awareness among non-experts of how much energy is required by different activities and appliances is generally low, which can lead to wrong prioritizations. In this study, we have developed an interactive tool to increase “energy awareness”, and performed a longitudinal study to evaluate its effect. A group of 58 students first did a test to benchmark their current energy awareness, where their current knowledge of energy used for 14 different activities, such as driving vehicles and using home appliances, was measured. They then tried the interactive learning tool for 10 min. Next, they did the same test immediately after trying the tool, then again one week after trying the tool, and finally again six months after trying the tool. The results showed a significant learning effect in energy awareness with a “huge” effect size of 2.25 immediately after the intervention, a “very large” effect size of 1.70 after one week, and a “large” effect size of 0.93 after six months. The results further showed that the respondents consistently underestimated what 100 kWh could be used for, and especially so for appliances and activities requiring little energy. Before the intervention, on average they underestimated how much 100 kWh could be used for by 95.2%, and six months after the intervention the underestimation was 86.8%.

  • 48.
    Bohne, Ulrica
    et al.
    KTH Royal Inst Technol.
    Zapico, Jorge Luis
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Media Technology. KTH Royal Inst Technol.
    Katzeff, Cecilia
    KTH Royal Inst Technol;Interact Swedish ICT, Eskilstuna.
    The EcoPanel: designing for reflection on greener grocery shopping practices2015In: Proceedings of Enviroinfo and ICT for Sustainability 2015, 2015, p. 221-228Conference paper (Refereed)
    Abstract [en]

    While the purchases of organic food are increasing rapidly, it accounts for only a small fraction of the total consumption, and there is still a big gap between consumer values awareness and the actual consumption. This article explores how detailed personal feedback could help the households to gain insight and reflect on their consumption, the text presents the design process of developing a prototype, the EcoPanel, in collaboration with a major player on the food retail market. Based on the access to detailed tracking of purchase data, the aim of the design was to provide relevant feedback to facilitate for reflection on the user's own food choices. The design prototype is intended to serve as an instrument for insight and reflection and to bring unconscious aspects of grocery shopping to conscious awareness. Following a research through design approach, this article describes the interdependent steps in designing the EcoPanel and design decisions playing a role for users' critical reflection of their food choice practices. It discusses the intention of each module in providing insight. Finally, we discuss how a social practice perspective may be useful for identifying fruitful future research into the design for more sustainable grocery shopping practices

  • 49.
    Bonnevier, Jesper
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Designing an Interactive Video Editing Tool for Teachers2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study aims to find the answers to how an online interactive video editing tool for teachers to use would be designed. To find out the answers to this, students studying to become teachers and experienced teachers were interviewed and used for observations and usability testing of a prototype. In total there were 27 unique data gathering situations with 11 unique participants. The five teacher students who were participating were all teacher students at Linnaeus University in Växjö. The six experienced teachers have been teaching for many years and are currently lecturing teachers about new technology that can be used in the classroom. The result from interviews, observations and literature search contributed to a list of requirements which in turn became a prototype. What has been discovered is that teachers need a tool which is easy to use with interactions and functions such as adding clickable annotations to clips and creating playlists which will help teachers plan ahead and save time during lectures.

  • 50.
    Borgo, Rita
    et al.
    Kings College London, UK.
    Lee, Bongshin
    Microsoft Research, USA.
    Bach, Benjamin
    Microsoft Research - Inria, France.
    Fabrikant, Sara
    University of Zurich, Switzerland.
    Jianu, Radu
    City University London, UK.
    Kerren, Andreas
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Computer Science.
    Kobourov, Stephen
    University of Arizona, USA.
    McGee, Fintan
    Luxembourg Institute of Science and Technology, Luxembourg.
    Micallef, Luana
    Helsinki Institute for Information Technology, Finland.
    von Landesberger, Tatiana
    Darmstadt University, Germany.
    Ballweg, Katrin
    Darmstadt University, Germany.
    Diehl, Stephan
    University Trier, Germany.
    Simonetto, Paolo
    Swansea University, UK.
    Zhou, Michelle
    Juji, USA.
    Crowdsourcing for Information Visualization: Promises and Pitfalls2017In: Evaluation in the Crowd: Crowdsourcing and Human-Centered Experiments / [ed] Daniel Archambault, Helen Purchase, and Tobias Hoßfeld, Springer Publishing Company, 2017, p. 96-138Chapter in book (Refereed)
    Abstract [en]

    Crowdsourcing offers great potential to overcome the limitations of controlled lab studies. To guide future designs of crowdsourcing-based studies for visualization, we review visualization research that has attempted to leverage crowdsourcing for empirical evaluations of visualizations. We discuss six core aspects for successful employment of crowdsourcing in empirical studies for visualization – participants, study design, study procedure, data, tasks, and metrics & measures. We then present four case studies, discussing potential mechanisms to overcome common pitfalls. This chapter will help the visualization community understand how to effectively and efficiently take advantage of the exciting potential crowdsourcing has to offer to support empirical visualization research.

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