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  • 551.
    Greef, Tjerk de
    et al.
    Delft University of Technology.
    Gullström, Charlie
    Royal Institute of Technology.
    Handberg, Leif
    Royal Institute of Technology.
    Parnes, Peter
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Nefs, Harold
    Delft University of Technology.
    Shared mediated workspaces2012Conference paper (Refereed)
    Abstract [en]

    Shared mediated spaces provide viable alternatives for meetings and interactions. The development of collaborative mediated workspaces and shared negotiation spaces will have a fundamental impact on all human practices. Previous design-led research, has identified spatial design concepts, such as mediated gaze, and spatial montage, which, if unaddressed, may be said to impose friction, and thus impact negatively on the experience of mediated presence. The current paper discusses a set of conceptual tools for presence design, in relation to a prototype that is currently being developed by an interdisciplinary academic work group: The Mediated Sketching Table. The prototype combines analogue and digital interaction tools and technologies including HTML5 and WebRTC. Here, we present our initial observations when using the prototype and discuss possible ways to overcome design friction in the prototype. We acknowledge that mediated presence cannot be ensured by design or technology alone. However, by monitoring various design features, presence designers can seek to reduce the friction that otherwise inhibits mediated presence, mutual trust, knowledgesharing, and teamwork efficiency.

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  • 552.
    Granlund, Daniel
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Brännström, Robert
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Smart city: the smart sewerage2012In: Proceedings of the 37th IEEE Conference on Local Computer Networks Workshops (LCN Workshops): 6th IEEE Workshop On User MObility and VEhicular Networks, Piscataway, NJ: IEEE Computer Society Press , 2012, p. 856-859Conference paper (Refereed)
    Abstract [en]

    This paper describes a sensor-based system for monitoring of sewer flooding. A global trend in Smart Cities is the installation of sensors for surveillance of the city infrastructure. The presented system is mounted in a number of strategic sewers for initial evaluation. In order to monitor the natural variations of the sewer (including daily variations) the system should be able to integrate into normal monitoring/alarm systems. The communication channel and mounting position (sewer well in the ground) put limitations on the system.

  • 553.
    Kikhia, Basel
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Boytsov, Andrey
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Hallberg, Josef
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Sani, Zaheer ul Hussain
    Jonsson, Håkan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Synnes, Kåre
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Structuring and presenting lifelogs based on location data2012Report (Other academic)
    Abstract [en]

    Lifelogging techniques help individuals to log their life and retrieve important events, memories and experiences. Structuring lifelogs is a major challenge in lifelogging systems since the system should present the logs in a concise and meaningful way to the user. In this article the authors present a novel approach for structuring lifelogs as places and activities based on location data. The structured lifelogs are achieved using a combination of density-based clustering algorithms and convex hull construction to identify the places of interest. The periods of time where the user lingers at the same place are then identified as possible activities. In addition to structuring lifelogs the authors present an application in which images are associated to the structuring results and presented to the user for reviewing. The proposed approach allows automatic inference of information about significant places and activities, which generates structured image-annotated logs of everyday life.

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  • 554.
    Rana, Juwel
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Kristiansson, Johan
    Synnes, Kåre
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Supporting ubiquitous interaction in dynamic shared spaces through automatic group formation based on social context2012In: ASE International Conference on Social Informatics, Washington D.C., USA: December 14-16, 2012, Piscataway, NJ: IEEE Computer Society Press , 2012, p. 121-130Conference paper (Refereed)
    Abstract [en]

    This paper investigates how the management of groups that communicate electronically, such as group formation, can be simplified based on users’ context and social relations. This work builds on a framework for Aggregated Social Graphs, where each node represents the relational strength to other users. The strength of a relation is calculated by utilizing information on how we communicate using mobile phone calls, emails, and social networks in combination with additional sources of information such as from calendars. A contextual group management schema is presented where contextual parameters such as tags, locations and objects are used to prune an aggregated social graph in order to automatically form a group.The schema is implemented in a runtime environment based on the Distributed Shared Memory service available at Ericsson Labs. The feasibility of the proposed schema is then studied through a prototype implementation both in a web-browser and as a mobile app. The study shows that a group can be formed automatically and that a lightweight communication session then can be initiated for that group.

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  • 555.
    Rana, Juwel
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Synnes, Kåre
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Technical Foresight Report on Social Distribution Mechanisms2012Report (Other academic)
    Abstract [en]

    This report aims to identify trends, challenges and recommendations in regard of Social Distribution Mechanisms. This foresight will help expose future themes with high innovation and business potential based on a timeframe roughly 15 years ahead, or 2030! The purpose is to create a common outlook on the future of ICT and to establish a strong community across nodes and partner organizations.

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  • 556.
    Synnes, Kåre
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Kranz, Matthias
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Rana, Juwel
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Technical foresight report on social interaction for digital cities2012Report (Other academic)
    Abstract [en]

    This report aims to identify trends, challenges and recommendations in regard of Social Interaction for Digital Cities. This foresight will help expose future themes with high innovation and business potential based on a timeframe roughly 15 years ahead. The purpose is to create a common outlook on the future of ICT and to establish a strong community across EIT ICT Labs nodes and partner organizations.

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    FULLTEXT01
  • 557.
    Roalter, Luis
    et al.
    Technische Unviersität München.
    Linner, Thomas
    Technische Unviersität München.
    Möller, Andreas
    Technische Unviersität München.
    Diewald, Stefan
    Technische Unviersität München.
    Kranz, Matthias
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    The healthcare and motivation seat: a survey with the GewoS chair2012In: Mensch & Computer 2012: Workshopband : 12. fachübergreifende Konferenz für interaktive und kooperative Medien ; interaktiv informiert - allgegenwärtig und allumfassend!? / [ed] Harald Reiterer; Oliver Deussen, München: Oldenburg Wissenschaftsverlag , 2012Conference paper (Refereed)
    Abstract [en]

    The demographic change in the world’s population raises new problems for healthcare, such as rising costs for caretaking on elderly people. Ambient Assisted Living (AAL) aims at assisting elderly people through technical equipment to manage their daily tasks in their own homes. One of the important approaches is to monitoring vital parameters without actually sending nursing staff to the person in need of care. Additionally, by including motivational factors (e.g. sports and fitness programs), the person’s health state can be influenced. In this paper, we present a survey within a group of elderly people aged between 40 and 70 years, which is representative for the end-user group the GewoS Chair is designed for. Furthermore, we will discuss the elderly people’s behavior when dealing with new technologies and systems improving further attempts on this target group.

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  • 558. Wallin, Stefan
    et al.
    Leijon, Viktor
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Nordlander, Johan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Bystedt, Niklas
    Yalt.
    The semantics of alarm definitions: enabling systematic reasoning about alarms2012In: International Journal of Network Management, ISSN 1055-7148, E-ISSN 1099-1190, Vol. 22, no 3, p. 181-198Article in journal (Refereed)
    Abstract [en]

    The development and integration of an alarm interface between network elements and a network management system is a costly process, largely because of the informal way in which alarm interfaces are expressed and communicated. Low-quality alarm documentation and confusion around fundamental concepts like alarm states and alarm types are typical consequences of current practices. If alarm interfaces were expressed in a more formal manner, costs could be reduced and more advanced analysis and automation would be enabled. We present a novel approach to alarm interfaces by providing a formal alarm model together with a domain-specific language that allows us to specify both the alarm models and the constraints placed on the alarm models in a consistent manner. This means that we can verify the consistency of an alarm interface and automatically generate artifacts such as alarm correlation rules or alarm documentation based only on the model

  • 559.
    Möller, Andreas
    et al.
    Technische Unviersität München.
    Kray, Christian
    University of Münster.
    Roalter, Luis
    Technische Unviersität München.
    Diewald, Stefan
    Technische Unviersität München.
    Kranz, Matthias
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Tool Support for Prototyping Interfaces for Vision-Based Indoor Navigation2012Conference paper (Refereed)
    Abstract [en]

    Vision-based approaches are a promising method for indoor navigation, but prototyping and evaluating them poses several challenges. These include the effort of realizing the localization component, difficulties in simulating real-world behavior and the interaction between vision-based localization and the user interface. In this paper, we report on initial findings from the development of a tool to support this process. We identify key requirements for such a tool and use an example vision- based system to evaluate a first prototype of the tool.

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  • 560.
    Möller, Andreas
    et al.
    Technische Unviersität München.
    Michahelles, Florian
    ETH Zurich.
    Diewald, Stefan
    Technische Unviersität München.
    Roalter, Luis
    Technische Unviersität München.
    Kranz, Matthias
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Update Behavior in App Markets and Security Implications: A Case Study in Google Play2012In: Research in the LARGE: Proceedings of the 3rd International Workshop. Held in Conjunction with Mobile HCI / [ed] Benjamin Poppinga, 2012, p. 3-6Conference paper (Refereed)
    Abstract [en]

    Digital market places (e.g. Apple App Store, Google Play) have become the dominant platforms for the distribution of software for mobile phones. Thereby, developers can reach millions of users. However, neither of these market places today has mechanisms in place to enforce security critical updates of distributed apps. This paper investigates this problem by gaining insights on the correlation between published updates and actual installations of those. Our findings show that almost half of all users would use a vulnerable app version even 7 days after the fix has been published. We discuss our results and give initial recommendations to app developers.

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  • 561.
    Brox, Ellen
    et al.
    Northern Research Institute.
    Evertsen, Gunn
    Northern Research Institute.
    Bomark, Peter
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Hirche, Johannes
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Yliräisänen-Seppänen, Pia
    Rovaniemi University of Applied Sciences.
    User centric social diabetes game design for children2012In: Proceeding of the 16th International Academic MindTrek Conference 2012: Envision Future Media Environments, New York: Association for Computing Machinery, Inc. , 2012, p. 291-293Conference paper (Refereed)
    Abstract [en]

    Children recently diagnosed with diabetes type 1 require lots ofinformation and feel scared, alone and different. Most of theexisting educational material is on paper. Games with relevantlearning content are mainly small minigames in English. There isa need for more material with a focus on user needs, particularlylearning–by-doing material. Peer support is known to beimportant for this user group. We present a concept for a sociallearning game that is engaging and fun for diabetic children.

  • 562.
    Bergvall-Kåreborn, Birgitta
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    Broberg, Anders
    Umeå universitet.
    Lassinantti, Josefin
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    Davoli, Lorenzo
    Umeå universitet.
    Kuenen, Stoffel
    Umeå universitet.
    Palmquist, Lena
    Umeå universitet.
    Parnes, Peter
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Ståhlbröst, Anna
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    Synnes, Kåre
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Wennberg, Paula
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Distance- Spanning Technology.
    User toolkits for citizen-centric mobild service innovation2012In: eChallenges e-2012 Conference Proceedings / [ed] Paul Cunningham; Miriam Cunningham, IIMC International Information Management Corporation , 2012Conference paper (Refereed)
    Abstract [en]

    Around the world, there is an ongoing shift from en economy focusing on product development to an economy with focus on digital service development. An ongoing initiative in Europe to support this shift is the Internet of Services (IoS) which strives for a situation where everything that is needed to use a software is available as a service. The aim of this paper is to present a toolkit that non-programmers can use develop their own innovative mobile services. This environment strives to put forth a situation where technologies are made available as components that easily can be composed into a mobile services by just about anyone. This has tremendous impact on the feasibility of citizen-centric services where citizens create apps based on their current needs in their contemporary situation.

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  • 563.
    Rana, Juwel
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Synnes, Kåre
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Utilizing ego-centric social graphs to support social actorship: social recommendations for nomadic citizens2012Report (Other academic)
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  • 564.
    Kilinc, Caner
    et al.
    Luleå University of Technology.
    Booth, Todd
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    WallDroid: cloud assisted virtualized application specific firewalls for the Android OS2012In: 2012 IEEE 11th International Conference on Trust, Security and Privacy in Computing and Communications - TrustCom-2012: 11th IEEE Int. Conference on Ubiquitous Computing and Communications, IUCC-2012, Piscataway, NJ: IEEE Computer Society Press , 2012, p. 877-883Conference paper (Refereed)
    Abstract [en]

    Security is becoming an increasingly important feature of today's mobile environment where users download unknown apps and connect their smartphones to unknown networks while roaming. This paper proposes and evaluates an enhanced security model and architecture, WallDroid, enabling virtualized application specific firewalls managed by the cloud. The WallDroid solution can be considered as an Android Firewall Application but with some extra functionality. Key components used by the solution include VPN technologies like the Point to Point Tunneling Protocol (PPTP) and the Android Cloud to Device Messaging Framework (C2DM). Our solution is based on the cloud keeping track of millions of applications and their reputation (good, bad, or unknown) and comparing traffic flows of applications with a list of known malicious IP servers. We describe a prototype implementation and evaluate our solution.

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  • 565.
    Johansson, Dan
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Web-based adaptive application mobility2012In: Proceedings of the 1st IEEE International Conference on Cloud Networking, Piscataway, NJ: IEEE Communications Society, 2012, p. 87-94Conference paper (Refereed)
    Abstract [en]

    Application mobility is achieved when migrating an application with its code, states and all related information from one device to another during its execution. As traditional applications are being challenged by apps, we believe it is time to rethink the notion of application mobility and explore the concept from a web perspective. More specifically, this paper aims to address the challenges associated with application mobility through mapping these against features within modern web technologies, analyzing their ability to meet the specific requirements of application mobility. An architectural proposal is described where we deploy application mobility using web technologies. We show that the emerging HTML5 standard along with related API:s and frameworks can provide an environment for delivering application mobility that strongly meets the requirements of support for offline work and heterogeneous environments.

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  • 566.
    Boytsov, Andrey
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Abdallah, Zahraa
    Caulfield School of Information Technology, Monash University.
    Where have you been?: Using location clustering and context awareness to understand places of interest2012In: Internet of things, smart spaces, and next generation networking: 12th international conference, NEW2AN 2012, and 5th Conference on Smart Spaces, ruSMART 2012, St. Petersburg, Russia, August 27-29, 2012 : proceedings / [ed] Sergey Andreev; Yevgeni Koucheryavy ; Sergey Balandin, Heidelberg: Encyclopedia of Global Archaeology/Springer Verlag, 2012, p. 51-62Conference paper (Refereed)
    Abstract [en]

    Mobile devices have access to multiple sources of location data, but at any particular time often only a fraction of the location information sources is available. Fusion of location information can provide reliable real-time location awareness on the mobile phone. In this paper we propose and evaluate a novel approach to detecting the places of interest based on density-based clustering. We address both extracting the information about relevant places from the combined location information, and detecting the visits to known places in the real time. In this paper we also propose and evaluate ContReMAR application - an application for mobile context and location awareness. We use Nokia MDC dataset to evaluate our findings, find the proper configuration of clustering algorithm and refine various aspects of place detection

  • 567.
    Mitra, Karan
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A decision-theoretic approach for quality of experience measurement and prediction2011In: 2011 IEEE International Conference on Multimedia and Expo, (ICME 2011): Barcelona, Spain, 11 - 15 July 2011 / [ed] Irene Cheng, Piscataway, NJ: IEEE Communications Society, 2011Conference paper (Refereed)
    Abstract [en]

    This paper presents a pioneering context-aware approach for quality of experience (QoE) measurement and prediction. The proposed approach incorporates an intuitive context-aware framework and decision theory. It is capable of incorporating several QoE related classes and context information to correctly measure and predict the overall QoE on a single scale. Our approach can be used in measuring and predicting QoE in both lab and living-lab settings based on user, device and network related context parameters. The predicted QoE can be beneficial for network operators to minimize network churn and can help application developers to build smart user-centric applications. We perform extensive experimentation and the results validate our approach.

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  • 568.
    Johansson, Dan
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Andreas
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A MIP-P2P based architecture for application mobility2011In: Proceedings of the 10th International Conference on Mobile and Ubiquitous Multimedia: MUM '11, New York: ACM Digital Library, 2011, p. 85-93Conference paper (Refereed)
    Abstract [en]

    Mobility exists in many shapes; when migrating a running application (code, states and data) from one device to another, one has achieved application mobility. In this article we combine this mobility type with context awareness, defiining context awareness supported application mobility (CASAM) as when using context in the act of moving an application between hosts during its execution, to provide relevant information and/or services, where relevancy depends on the user's task. We identify and present five CASAM challenges, that are used to create requirements for a CASAM architecture. A proposal for an architecture, building on peer-to-peer (P2P) technology in combination with mobile IP, is then presented, addressing the identified challenges, providing a decentralized framework for global application mobility. As such, our architecture differs from earlier centralized and/or locally bound solutions for application mobility.

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  • 569.
    Mitra, Karan
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A probabilistic context-aware approach for quality of experience measurement in pervasive systems2011In: Proceedings of the 26th Annual ACM Symposium on Applied Computing 2011: Taichung, Taiwan, March 21 - 24, 2011, New York: ACM Digital Library, 2011, p. 419-424Conference paper (Refereed)
    Abstract [en]

    In this paper, we develop a novel context-aware approach for quality of experience (QoE) modeling, reasoning and inferencing in mobile and pervasive computing environments. The proposed model is based upon a state-space approach and Bayesian networks for QoE modeling and reasoning. We further extend this context model to incorporate influence diagrams for efficient QoE inferencing. Our approach accommodates user, device and quality of service (QoS) related context parameters to determine the overall QoE of the user. This helps in user-related media, network and device adaptation. We perform experimentation to validate the proposed approach and the results verify its modeling and inferencing capabilities.

  • 570.
    Kang, Yong-Bin
    et al.
    Faculty of Information Technology, Monash University.
    Krishnaswamy, Shonali
    Faculty of Information Technology, Monash University.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A retrieval strategy using the integrated knowledge of similarity and associations2011In: Database systems for advanced applications: 16th international conference, DASFAA 2011, Hong Kong, China, April 22-25, 2011 : proceedings / [ed] Jeffrey Xu Yu; Myoung Ho Kim; Rainer Unland, Heidelberg: Encyclopedia of Global Archaeology/Springer Verlag, 2011, p. 16-30Conference paper (Refereed)
    Abstract [en]

    Retrieval is often considered the most important task in Case-Based Reasoning (CBR), since it lays the foundation for overall performance of CBR systems. In CBR, a typical retrieval strategy is realized through similarity knowledge encoded in similarity measures. This strategy is often called similarity-based retrieval (SBR). This paper proposes and validates that association analysis techniques can be used to improve SBR. We propose a retrieval strategy USIMSCAR that performs the retrieval task by integrating similarity and association knowledge. We show its reliability, in comparison with several retrieval methods implementing SBR, using datasets from UCI ML Repository

  • 571.
    Granlund, Daniel
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A scalability study of AAA support in heterogeneous networking environments with global roaming support2011In: TrustCom 2011: 2011 international joint conference of IEEE TrustCom-11, IEEE ICESS-11 / FCST-11 : 16-19 November 2011, Changsha, Hunan, P. R. China / [ed] Guojun Wang, Los Alamitos, Calif: IEEE Computer Society Press , 2011, p. 488-493Conference paper (Refereed)
    Abstract [en]

    In this paper, we present a scalability study of AAA support in mobile heterogeneous access networks with respect to server and network load related to AAA processes using the RADIUS protocol. Technologies such as IEEE 802.11, CDMA 2000 and UMTS which all support the RADIUS protocol for AAA handling are discussed and analyzed. Typical performance data are gathered and complemented with a theoretical study in order to achieve an overview of what parameters will affect the performance and scalability of the network. Also, guidelines are developed for network design in order to achieve the desired performance for a given number of users. Results of this study include the conclusion that the main bottleneck of the AAA procedure is not necessarily the AAA server CPU power. Aside the cases with a high proportion of computationally intensive WiFi sign-ons with strong encryption, performance issues may be caused by AAA server network connection bandwidth, and RAM memory. In cases where a high number of users reside in the same user database, database performance becomes a significant issue. In order to achieve better performance, CPU load balancing over several servers may be performed.

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  • 572.
    Schmidt, Mischa
    NEC Laboratories Europe, NEC Europe Ltd., Heidelberg.
    An Overview of IPTV and Video Services2011In: Advances in Next Generation Services and Service Architectures, River Publishers, 2011, p. 177-196Chapter in book (Refereed)
    Abstract [en]

    This chapter provides an overview of IPTV and Video Services in managedand unmanaged IP networks. For this, it first separates IP based services fromthe traditional TV and Video services. This separation is intended to draw theawareness to the commonalities and the differences of both approaches. Italso introduces an understanding of the new capabilities implied by deliveringTV and Video services over IP based networks. To build a common understanding of the innovative services in the IP based environment, a collection of typical IPTV and Video services discussed in the industry is presented afterwards.Subsequently, we discern managed from unmanaged IP networks for providingIP based TV and Video services. Here the effects on IPTV and VideoServices of both network models are discussed: their potentials, benefits andadvantages as well as their shortcomings, threats and challenges. For themanaged network approach a dedicated section to sketch the two main architectural approaches to IPTV services currently discussed in the industry isintroduced: IMS-based IPTV and non-IMS based IPTV. This section leads toan understanding of their main differences and the implication of using oneor the other.In conclusion of this chapter, the most prominent obstacles for the risingIPTV and Video Services are summarized. Here we also describe the conceptof hybrid approaches mixtures between traditional broadcasting and IP servicesthat are investigated at present in the industry to address some of thechallenges mentioned earlier in this chapter.

  • 573.
    Wallin, Stefan
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Wikström, Claes
    Tail-f.
    Automating network and service configuration using NETCONF and YANG2011In: Proceedings of LISA 11: 25th Large Installation System Administration Conference, USENIX - The Advanced Computing Systems Association, 2011, p. 267-279Conference paper (Refereed)
    Abstract [en]

    Network providers are challenged by new requirements for fast and error-free service turn-up. Existing approaches to configuration management such as CLI scripting, device-specific adapters, and entrenched commercial tools are an impediment to meeting these new requirements. Up until recently, there has been no standard way of configuring network devices other then SNMP and SNMP is not optimal for configuration management. The IETF has released NETCONF and YANG which are standards focusing on Configuration management. We have validated that NETCONF and YANG greatly simplify the configuration management of devices and services and still provide good performance. Our performance tests are run in a cloud managing 2000 devices. Our work can help existing vendors and service providers to validate a standardized way to build configuration management solutions.

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  • 574.
    Saguna, Saguna
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Chakraborty, Dipanjan
    IBM Research, India Research Lab.
    Complex activity recognition using context driven activity theory in home environments2011In: Smart spaces and next generation wired/wireless networking: 11th international conference, NEW2AN 2011 and 4th Conference on Smart Spaces, RuSMART 2011, St. Petersburg, Russia, August 22-15, 2011 ; proceedings / [ed] Sergey Balandin; Yevgeni Koucheryavy; Honglin Hu, Heidelberg: Encyclopedia of Global Archaeology/Springer Verlag, 2011, p. 38-50Conference paper (Refereed)
    Abstract [en]

    This paper proposes a context driven activity theory (CDAT) and reasoning approach for recognition of concurrent and interleaved complex activities of daily living (ADL) which involves no training and minimal annotation during the setup phase. We develop and validate our CDAT using the novel complex activity recognition algorithm on two users for three weeks. The algorithm accuracy reaches 88.5% for concurrent and interleaved activities. The inferencing of complex activities is performed online and mapped onto situations in near real-time mode. The developed systems performance is analyzed and its behavior evaluated

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  • 575.
    Boytsov, Andrey
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Context reasoning, context prediction and proactive adaptation in pervasive computing systems2011Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The paradigm of pervasive computing aims to integrate the computing technologies in a graceful and transparent manner, and make computing solutions available anywhere and at any time. Different aspects of pervasive computing, like smart homes, smart offices, social networks, micromarketing applications, PDAs, etc. are becoming a part of everyday life. Context of pervasive computing system is any piece of information that can be of possible interest to the system. Context often includes location, time, activity, surroundings, etc. One of the core features of pervasive computing systems is context awareness – the ability to use context information to the benefit of the system. The thesis proposes a set of context prediction and situation prediction methods on top of enhanced situation awareness mechanisms. Being aware of the future context enables a pervasive computing system to choose the most efficient strategies to achieve its stated objectives and therefore a timely response to the upcoming situation can be provided. This thesis focuses on the challenges of context prediction, but in order to become really efficient and useful, context prediction approaches need to be gracefully integrated with different other aspects of reasoning about the context. This thesis proposes a novel integrated approach for proactively working with context information. In order to become efficient, context prediction should be complemented with proper acting on predicted context, i.e. proactive adaptation. The majority of current approaches to proactive adaptation solves context prediction and proactive adaptation problems in sequence. This thesis identifies the shortcomings of that approach, and proposes an alternative solution based on reinforcement learning techniques. The concept of situation provides useful generalization of context data and allows eliciting the most important information from the context. The thesis proposes, justifies and evaluates improved situation modeling methods that allow covering broader range of real-life situations of interest and efficiently reason about situation relationships. The context model defines the pervasive computing system’s understanding of its internal and external environments, and determines the input for context prediction solutions. This thesis proposes novel methods for formal verification of context and situation models that can help to build more reliable and dependable pervasive computing systems and avoid the inconsistent context awareness, situation awareness and context prediction results. The architecture of pervasive computing system integrates all the aspects of context reasoning and governs the interaction and collaboration between different context processing mechanisms. This thesis proposes, justifies and evaluates the architectural support for context prediction methods. The novel architectural solutions allow encapsulating various practical issues and challenges of pervasive computing systems and handling them on low levels of context processing, therefore, supporting the efforts for efficient context prediction and proactive adaptation.

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  • 576.
    Rahmani, Rahim
    et al.
    Mittuniversitetet.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Kanter, Theo
    Mittuniversitetet.
    Design of active queue management for robust control on access router for heterogeneous networks2011In: EURASIP Journal on Wireless Communications and Networking, ISSN 1687-1472, E-ISSN 1687-1499, Vol. 2011, article id 946498Article in journal (Refereed)
    Abstract [en]

    The Internet architecture is a packet switching technology that allows dynamic sharing of bandwidth among different flows with in an IP network. Packets are stored and forwarded from one node to the next until reaching their destination. Major issues in this integration is congestion control and how to meet different quality of service requirements associated with various services. In other words streaming media quality degrades with increased packet delay and jitter caused by network congestion. To mitigate the impact of network congestion various techniques have been used to improve multimedia quality and one of those techniques is Active Queue Management (AQM). Access routers require a buffer to hold packets during times of congestion. A large buffer can absorb the bursty arrivals and this tends to increase the link utilizations but results in higher queuing delays. Traffic burstiness has a considerable negative impact on network performance. AQM is now considered an effective congestion control mechanism for enhancing transport protocol performance over wireless links. In order to have good link utilization it is necessary for queues to adapt to varying traffic loads. This paper considers a particular scheme which is called Adaptive AQM (AAQM) and studies its performance in the presence of feedback delays and its ability to maintain a small queue length as well as its robustness in the presence of traffic burstiness. The paper also presents a method based on the well-known Markov Modulated Poisson Process (MPP) to capture traffic burstiness and buffer occupancy. To demonstrate the generality of the presented method an analytic model is described and verified by extensive simulations of different adaptive AQM algorithms. The analysis and simulations show that AAQM outperforms the other AQMs with respect to responsiveness and robustness.

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  • 577.
    Mitra, Karan
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Dynamic Bayesian networks for sequential quality of experience modelling and measurement2011In: Smart Spaces and Next Generation Wired/Wireless Networking: 11th International Conference, NEW2AN 2011, and 4th Conference on Smart Spaces, ruSMART 2011, St. Petersburg, Russia, August 22-25, 2011. Proceedings / [ed] Sergey Balandin; Yevgeni Koucheryavy; Honglin Hu, Encyclopedia of Global Archaeology/Springer Verlag, 2011, p. 135-146Conference paper (Refereed)
    Abstract [en]

    This paper presents a novel context-aware methodology for modelling and measuring user-perceived quality of experience (QoE) over time. In particular, we create a context-aware model for QoE modelling and measurement using dynamic Bayesian networks (DBN) and a context-aware state-space approach. The proposed model is then used to infer and determine users’ QoE in a sequential manner. We performed experimentation to validate the proposed model. The results prove thatit can efficiently model, reason and measure QoE of the users’.

  • 578.
    Boytsov, Andrey
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    ECSTRA: Distributed context reasoning framework for pervasive computing systems2011In: Smart Spaces and Next Generation Wired/Wireless Networking: 11th International Conference, NEW2AN 2011, and 4th Conference on Smart Spaces, ruSMART 2011, St. Petersburg, Russia, August 22-25, 2011. Proceedings / [ed] Sergey Balandin; Yevgeni Koucheryavy; Honglin Hu, Springer Science+Business Media B.V., 2011, p. 1-13Conference paper (Refereed)
    Abstract [en]

    Pervasive computing solutions are now being integrated into everyday life. Pervasive computing systems are deployed in homes, offices, hospitals, universities. In this work we present ECSTRA – Enhanced Context Spaces Theory-based Reasoning Architecture. ECSTRA is a context awareness and situation awareness framework that aims to provide a comprehensive solution to reason about the context from the level of sensor data to the high level situation awareness. Also ECSTRA aims to fully take into account the massively multiagent distributed nature of pervasive computing systems. In this work we discuss the architectural features of ECSTRA, situation awareness approach and collaborative context reasoning. We also address the questions of multi-agent coordination and efficient sharing of reasoning information. ECSTRA enhancements related to those problems are discussed. Evaluation of proposed features is also discussed.

  • 579.
    Elkotob, Muslim
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Efficient and systematic network resource management2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The demand for network resources (e.g. forwarding capacity, buffer space) by increasingly used real-time multimedia applications is growing. Moreover, their stringent performance requirements (e.g. delay and jitter bounds) pose challenges on network resource management (RM). RM determines how available resources are modeled and distributed to achieve a performance goal such as assuring forwarding quality to real-time multimedia applications. Improvements to existing RM mechanisms can avoid performance limitations of networks by facilitating more efficient use of scarce resources. For example, in a vehicular to infrastructure (V2I) communication scenario that uses IP Multimedia Subsystem (IMS) lacking RM support for multicast, the 3G downlink quickly becomes a bottleneck although some information is addressed to multiple receivers. The main goal of this thesis is to develop RM algorithms and protocols that improve forwarding capacity utilization and remove performance bottlenecks. An additional goal is to improve the scalability of existing RM mechanisms. Three architectural paradigms are covered to demonstrate the advantages of efficient and systematic network RM: open access networks (OAN), next generation networks (NGN), and heterogeneous access networks (HAN). For OAN, a cross-layer signaling technique called parameter injection was developed. It reduces the signaling overhead and update time for real-time multimedia sessions over Wi-Fi while autonomously selecting the format and CODEC that best match the current resource settings. Within NGN, a resource management protocol is proposed for extending unicast signaling in IMS with multicast capabilities. The contribution uses adaptive and dynamic group size selection to improve resource utilization on the 3G downlink for the signaling and data planes. For HAN, an algorithm is proposed that predicts the best access network for achieving the highest QoE of a real-time multimedia session with the available QoS resources based on regression and statistical learning. In all three paradigms, the provided core contributions serve the common goal of achieving a performance edge in terms of efficiency and systematic operation with a limited amount of network resources.

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  • 580.
    Boytsov, Andrey
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Formal Verification of the Context Model: Enhanced Context Spaces Theory Approach2011Report (Other academic)
    Abstract [en]

    Pervasive computing is a paradigm that focuses on availability and non-intrusive integration of computing services into everyday life. Context awareness is the basic principle of pervasive computing. The important part of high-level context awareness is situation awareness – the ability to detect and reason about the real-life situations. The specifications of situations are often carried out manually by the experts. Therefore, the specification errors can be introduced. The specification errors cause the situation reasoning problems and context model inconsistency. In this article we propose and analyze the approach for formal verification of the situation definitions. Our solution uses as an input the situation specification in terms of low-level context features and the properties under verification, and then either formally proves that the specifications do comply with the expected property, or provide all possible counterexamples – the context conditions that will lead to situation awareness inconsistency. Evaluation and the complexity analysis of the proposed approach are also discussed.

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  • 581.
    Boytsov, Andrey
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    From sensory data to situation awareness: enhanced context spaces theory approach2011In: Ninth International Conference on Dependable, Autonomic and Secure Computing (DASC), Piscataway, NJ: IEEE Communications Society, 2011, p. 207-214Conference paper (Refereed)
    Abstract [en]

    High-level context awareness can be significantly improved by the recognition of real-life situations. The theory of context spaces is a context awareness approach that uses spatial metaphors to provide integrated mechanisms for both low-level and high-level context awareness and situation awareness. Taking context spaces theory situation awareness as a baseline, we propose and analyze the enhanced situation awareness techniques, which allow us to reason about broad class of real-life situations. We also improve reasoning about the relationships between situations, and discuss how it relates to newly proposed situation awareness approaches. Practical evaluation of the results is also discussed.

  • 582.
    Rana, Juwel
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Improving group communication by harnessing information from social networks and communication services2011Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    On-line social networking and communication services are increasingly popular methods to communicate with friends, family and communities. Statistics shows that users of services like Facebook and Twitter stretches across geographical locations, professions, age groups and habits. Smart mobile devices with Internet connectivity simplifies access to these services at anytime and from almost anywhere. However, the huge amount of user-generated content makes it difficult to identify useful information. A challenge is to create micro-communities where users may join in from heterogeneous social networks using proper user and identity management. The increasing number of social networks and communication services are also creating new challenges in social media content filtering, micro-community discovery, automatic group communication initialization.This licentiate thesis proposes to utilize social graphs for improving group communication. It therefore presents a framework that manages information harnessed from social-networking services and personal devices such as mobile phones and laptops. The framework can identify individual communication patterns and use these to calculate a social strength between users expressed as a weighted social graph.The central component of the framework is a social recommendation engine for social content filtering, group management and communication pattern discovery. The engine harness personalized social data (both content and contact) from the social-networking services and personal devices. The framework also contains methods for social strength calculation based on a unified interaction model that supports communication pattern discovery. A comparison study is presented together with the framework, which evaluates different social strength computation methods based on a simulated interaction dataset. The feasibility of social data collection from social networks and communication services are also discussed to illuminate potential benefits of the framework for the next generation of communication tools (such as mobile video conferencing).Evaluation of the framework is initially done by proof-of-concept prototypes that illustrate functional feasibility. Two prototypes are presented in this thesis, a presence information viewer that filters and prioritizes contacts and a real-time photo sharing application utilizing calendar data for initiation of group communication. In conclusion, improving group communication by offering services for micro-communities, based on our communication habits, personal interests and context (such as activity and location) is technically realistic and feasible.

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  • 583.
    Saguna, Saguna
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Inferring multiple activities of mobile users with activity algebra2011In: 12th International Conference on Mobile Data Management (MDM), 2011: 6-9 June Luleå, Sweden, Piscataway, NJ: IEEE Communications Society, 2011, p. 23-26Conference paper (Refereed)
    Abstract [en]

    This paper proposes a novel multiple activity recognition and reasoning approach where we use on-body sensor information along with other context information to infer mobile user activities which are both concurrent and interleaved. We develop and validate an activity algebra and a complex activity recognition algorithm for detecting these multiple activities. Activities are mapped onto situations using spatio-temporal analysis. We validate our approach by implementing a prototype and performing experiments in different scenarios using mobile devices

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  • 584.
    Handurukande, Sidath
    et al.
    Network Management Lab, LM Ericsson, Athlone, Ireland.
    Fedor, Szymon
    Network Management Lab, LM Ericsson, Athlone, Ireland.
    Wallin, Stefan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zach, Martin
    Siemens AG Austria, Vienna, Austria.
    Magneto approach to QoS monitoring2011In: Proceedings of the 12th IFIP/IEEE International Symposium on Integrated Network Management, Piscataway, NJ: IEEE Communications Society, 2011, p. 209-216Conference paper (Refereed)
    Abstract [en]

    Quality of Service (QoS) monitoring of end-user services is an integral and indispensable part of service management. However in large, heterogeneous and complex networks where there are many services, many types of end-user devices, and huge numbers of subscribers, it is not trivial to monitor QoS and estimate the status of Service Level Agreements (SLAs). Furthermore, the overwhelming majority of end-terminals do not provide precise information about QoS which aggravates the difficulty of keeping track of SLAs. In this paper, we describe a solution that combines a number of techniques in a novel and unique way to overcome the complexity and difficulty of QoS monitoring. Our solution uses a model driven approach to service modeling, data mining techniques on small sample sets of terminal QoS reports (from “smarter” end-user devices), and network level key performance indicators (N-KPIs) from probes to address this problem. Service modeling techniques empowered with a modeling engine and a purpose-built language hide the complexity of SLA status monitoring. The data mining technique uses its own engine and learnt data models to estimate QoS values based on N-KPIs, and feeds the estimated values to the modeling engine to calculate SLAs. We describe our solution, the prototype and experimental results in the paper.

  • 585.
    Zaslavsky, Arkady
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Chrysanthis, Panos K.
    University of Pittsburgh.
    Lee, Dik Lun
    University of Science and Technology, Hong Kong.
    Message from the general co-chairs2011Other (Other academic)
  • 586.
    Andersson, Karl
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Mostafa, Seraj Al Mahmud
    Luleå tekniska universitet.
    Islam, Raihan Ul
    Luleå tekniska universitet.
    Mobile VoIP user experience in LTE2011In: Proceedings of The 36th IEEE Conference on Local Computer Networks (LCN): 5th IEEE Workshop On User MObility and VEhicular Networks, IEEE Computer Society Press , 2011, p. 789-792Conference paper (Refereed)
    Abstract [en]

    3GPP Long-term Evolution (LTE) systems being deployed are fast gaining market shares. High data rates (approaching 100 Mbit/s in the downlink direction and 50 Mbit/s for uplink connections) and small delays are attractive features of LTE. Spectrum flexibility also makes deployment easy on various frequency bands in different parts of the world. However, as LTE offers packet switched services only, mobile broadband connectivity has become the dominant LTE application so far. This paper studies user-perceived quality of service for a mobile Voice over IP (VoIP) application in LTE. Results were achieved using the OPNET Modeler simulation environment.

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  • 587.
    Cherkaoui, S.
    et al.
    Université de Sherbrooke.
    Brännström, Robert
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    On-Move 2011: Message from the On-Move 2011 workshop chairs2011Other (Other academic)
  • 588.
    Andersson, Karl
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Optimized access network selection in a combined WLAN/LTE environment2011In: Wireless personal communications, ISSN 0929-6212, E-ISSN 1572-834X, Vol. 61, no 4, p. 739-751Article in journal (Refereed)
    Abstract [en]

    Multimode terminals equipped with multiple radio access technologies are becoming increasingly popular. At the same time, network operators and service providers seek opportunities to deliver seamless services cost effectively, leveraging a variety of radio access technologies using both licensed and unlicensed spectrum. In order to standardize the operations of such complex environments 3GPP is currently working on IP flow mobility and mobile data offload solutions. This article proposes and evaluates a new access network selection procedure in such a combined WLAN/LTE environment. The proposed solution takes not only parameters available in the mobile node and its current and candidate access networks into account, but performs an optimization on the heterogeneous wireless network level as well. An optimization model based on an approximate solution to the well-known bin packing problem is presented. Also, there is a signaling scheme for distribution handling presented. Results from simulations performed in OPNET Modeler show improvements compared to basing handover decisions on locally available information only.

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  • 589. Johansson, Dan
    et al.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Holmgren, Mikael
    Project: NIMO - Nordic Interaction and Mobility Research Platform2011Other (Other (popular science, discussion, etc.))
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  • 590.
    Saguna, Saguna
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Chakraborty, Dipanjan
    Recognizing concurrent and interleaved activities in social interactions2011In: Ninth International Conference on Dependable, Autonomic and Secure Computing (DASC), Piscataway, NJ: IEEE Communications Society, 2011, p. 230-237Conference paper (Refereed)
    Abstract [en]

    Social networks constitute an important research area where users are involved in social interactions and inform each other of activities they perform. In this paper a complex activity recognition system (SEMACT) is proposed, built and validated. Different activities performed by users form an activity hierarchy. We perform semantic reasoning by using ontological constructs and rules to recognize both concurrent and interleaved complex activities at different levels of granularity of this activity hierarchy. Different application domains require activity recognition systems to define and recognize activities at different levels of granularity. Our system tackles this problem by recognizing complex activities which are then shared across application domains using a generic API. A test-bed and prototype are built to validate our SEMACT system. Extensive experimentation is performed which demonstrates that high accuracy of 94.35% was achieved for the recognition of complex activities both concurrent and interleaved within computationally feasible time

  • 591.
    Granlund, Daniel
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Secure and scalable roaming support in heterogeneous access networks2011Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Mobility support for users connecting to the Internet is an increasing trend. Different types of access networks like WiFi, CDMA, and UMTS are available, creating a heterogeneous access network environment. In the Internet today, there are a number of providers of various sizes supporting different technologies. Moving between such operators different types of authentication methods are often used interrupting ongoing services. This, in combination with lacking roaming agreements makes mobility among them with maintained connectivity and uninterrupted services difficult or even impossible.This thesis proposes an extended functionality to the Authentication, Authorization and Accounting, (AAA) protocol that enables a single AAA infrastructure to exist in a heterogeneous network environment and that enables interconnection between different operators in a tree-like structure of AAA servers. Mobile devices will maintain their IP address while connected to a network different from the home network independent of the network access technology. Furthermore, a scalability study is carried out in order to determine what is required from an AAA system in order for it to perform when dealing with larger numbers of users, service providers as well as supporting new technologies. A method for providing information for handover decisions for intra- and inter-operator mobility is also proposed. The proposed method selects the access network that according to a metric based on jitter and delay shows best performance.Evaluations show that authentication and IP address assignment can be supported in an efficient way in comparison with state of the art for both Ethernet and PPP based access networks using a common AAA infrastructure. CPU, memory and network link capacity in the home AAA server are identified as the primary bottlenecks when discussing scalability in RADIUS based AAA infrastructures and guidelines are proposed to address scalability issues during system design. The metric proposed to support in handover decisions shows that bandwidth can be estimated with more than 90% accuracy for WiFi, CDMA, and UMTS access networks.

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  • 592.
    Brännström, Robert
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Granlund, Daniel
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Sensor monitoring of bridge movement: a system architecture2011In: Proceedings of The 36th IEEE Conference on Local Computer Networks (LCN): 5th IEEE Workshop On User MObility and VEhicular Networks, IEEE Communications Society, 2011, p. 797-800Conference paper (Refereed)
    Abstract [en]

    This paper describes a sensor-based accelerometermonitoring system for bridge monitoring. A system with 18 sensors will be mounted on a 130-meter long cable-strayed bridge that is built during the summer of 2011. In order to monitor the natural frequency of the bridge (including vibrations and damping) the system should manage accelerometer readings at 50 Hz. The communication channel, sample rate requirements and number of sensors put limitations on the system architecture.

  • 593.
    Johansson, Dan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Session mobility in multimedia services enabled by the cloud and peer-to-peer paradigms2011In: Proceedings of The 36th IEEE Conference on Local Computer Networks (LCN): 5th IEEE Workshop On User MObility and VEhicular Networks, IEEE Computer Society Press , 2011Conference paper (Refereed)
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  • 594.
    Kikhia, Basel
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Supporting lifestories through activity recognition and digital reminiscence2011Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This licentiate thesis discusses how lifelogging technologies can be used to build digital reminiscence systems. Lifelogging is a recent pervasive computing trend where different aspects of someone’s life are captured digitally. The aim of the proposed system is to create digital lifestories that can visualize the life of a person and provide a means for retrieving life experiences. The target users are people with mild dementia who have problems in navigating their daily life and in recalling previous events. The claim is that digital lifestories can be utilized for memory and reminiscence support as well as strengthen the bond between a person with mild dementia and his family. The main focus of the research study is about designing and developing digital reminiscence systems that can be used by people with mild dementia as aiding memory tools. Creating digital lifestories requires capturing of context data, such as places and people, and content data, such as sound and images, using pervasive lifelogging tools. The passive and continues capture of data results in the occurrence of false data and noise. For that, the system should reduce the collected data to not overload the user when reviewing the lifelogs. Another problem is that the life should be segmented in the form of activities that are searchable and accessible. Thus the collected lifelog data should be aggregated and structured into semantic activities and then represented as digital lifestories where context data can be retrieved together with related content. This licentiate thesis proposes solutions for filtering collected data to reduce the user’s efforts when reminiscing. The thesis also presents a method that uses prior knowledge of context data to improve the recognition of activities when creating the digital lifestories. In addition, locations where the user spends significant time can help in determining context parameters such as activities. This licentiate thesis proposes a novel approach that collects and clusters logged locations of the user to improve the activity recognition task. The presented approach defines possible places first, and it then identifies activities based on those places. Images, as content data, are then associated with the activities based on their timeframes so the user can review and adjust the data before saving it to his lifestory. The presented digital reminiscence system was evaluated through a field-test involving 10 people with mild dementia together with their caregivers. Healthcare professionals were also involved in the design and the evaluation of the system to improve the outcome of the study. The preliminary results indicate that the system indeed improves the quality of life for people with mild dementia, as their reminiscence processes are encouraged and that the communication with their surroundings increases in both volume and quality. The thesis shows that digital reminiscence systems, which describe life through activities, can increase the perceived quality of life for people with mild dementia. It also shows that activity recognition can be improved by using prior knowledge of context data and by automatic location clustering.

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  • 595.
    Saguna, Saguna
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Chakraborty, Dipanjan
    IBM Research, India Research Lab.
    Towards a robust concurrent and interleaved activity recognition of mobile users2011In: 12th International Conference on Mobile Data Management (MDM), 2011: Lulea, Sweden 6-9 June 2011, Piscataway, NJ: IEEE Communications Society, 2011, p. 297-298Conference paper (Refereed)
    Abstract [en]

    This paper proposes a situation and context-aware complex activity recognition system where we use on-body sensor information along with other context information to infer mobile user activities which are both concurrent and interleaved. We develop and validate our complex activity recognition algorithm for detecting these multiple complex activities. Activities are mapped onto situations using spatio-temporal analysis. We further build a test-bed in the social-networking domain to test and validate our approach in different scenarios using mobile devices

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  • 596.
    Wallin, Stefan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    UML visualization of YANG models2011In: Proceedings of the 12th IFIP/IEEE International Symposium on Integrated Network Management, Piscataway, NJ: IEEE Communications Society, 2011, p. 1129-1134Conference paper (Refereed)
    Abstract [en]

    Formal data-models are one of the corner-stones of automatic network management. We need semantic models that can be automatically interpreted by management applications. At the same time, human domain-experts need to be able to understand the models. This dualistic requirement has lead standard organizations to pick modeling approaches that prioritize either humans or automatic software. YANG is a semantically rich data-modeling language. We have defined a mapping of YANG to UML and a tool that renders UML diagrams from YANG models. This enables the benefits of formal languages for defining interfaces and automatically maintained UML diagrams to involve domain experts.

  • 597.
    Cherkaoui, S.
    et al.
    Sherbrooke University.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Welcome message from the ON-MOVE 2010 co-chairs2011Other (Other academic)
  • 598.
    Rahmani, R.
    et al.
    Department of Information Technology and Media, Mid-Sweden University.
    Kanter, T.
    Department of Information Technology and Media, Mid-Sweden University.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A self configuring fuzzy active queue management controller in heterogeneous networks2010In: ICT 2010: 2010 17th International Conference on Telecommunications, Piscataway, NJ: IEEE Communications Society, 2010, p. 634-641Conference paper (Refereed)
    Abstract [en]

    To achieve self configuring of Active Queue Management based on Fuzzy Logic Controller (FLC), we propose a Fuzzy Adaptive Active Queue Management Controller (FAAQMC). FAAQMC eliminates buffer overflow by adapting the buffer size to the required queue length with a control cycle time shorter than the mean inter-arrival time of a burst. This makes FAAQMC suitable to manage invariant burstiness or self-similar network traffic.

  • 599.
    Gaber, Mohamed Medhat
    et al.
    School of Computing, University of Portsmouth.
    Krishnaswamy, Shonali
    Centre for Distributed Systems and Software Engineering, Monash University.
    Gillick, Britt
    Centre for Distributed Systems and Software Engineering, Monash University.
    Nicoloudis, Nicholas
    Centre for Distributed Systems and Software Engineering, Monash University.
    Liono, Jonathan
    Centre for Distributed Systems and Software Engineering, Monash University.
    Taiar, Hasnain Al
    Centre for Distributed Systems and Software Engineering, Monash University.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Adaptive clutter-aware visualization for mobile data stream mining2010In: 22nd International Conference on Tools with Artificial Intelligence: proceedings : 27-29 October 2010, Arras, France, Los Alamitos, Calif: IEEE Communications Society, 2010, p. 304-311Conference paper (Refereed)
    Abstract [en]

    There is an emerging focus on real-time data stream analysis on mobile devices. A wide range of data stream processing applications are targeted to run on mobile handheld devices with limited computational capabilities such as patient monitoring, driver monitoring, providing real-time analysis and visualization for emergency and disaster management, real-time optimization for courier pick-up and delivery etc. There are many challenges in visualization of the analysis/data stream mining results on a mobile device. These include coping with the small screen real-estate and effective presentation of highly dynamic and real-time analysis. This paper proposes a generic theory for visualization on small screens that we term Adaptive Clutter Reduction ACR. Based on ACR, we have developed and experimentally validated a novel data stream clustering result visualization technique that we term Clutter-Aware Clustering Visualizer (CACV). Experimental results on both synthetic and real datasets using the Google Andriod platform are presented proving the effectiveness of the proposed techniques.

  • 600.
    Elkotob, Muslim
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Architectural, service, and performance modeling for an IMS-MBMS-based application2010In: IEEE International Conference on Communications (ICC), Piscataway, NJ: IEEE Communications Society, 2010Conference paper (Refereed)
    Abstract [en]

    This paper describes iRide (intelligent ride), an IP Multimedia Subsystem (IMS), Multimedia Broadcast Multicast Service (MBMS), and wireless sensor network (WSN) joint application. The core contributions of iRide are: IMS and WSN architectural integration on joint data processing and signaling levels, application logic for increased road safety, and network dimensioning for scalability and performance analysis. The iRide architecture is built and prototyped using IMS standard SIP (Session Initiation Protocol) and DIAMETER signaling together with 3GPP MBMS for more efficient service handling. OPNET simulations are used to conduct network dimensioning and performance analysis. Resource management in systems such as the one presented experiences several challenges in the form of bottlenecks and multicast dynamic group sizing is used as a key technique to make resources on the downlink data planemore efficiently managed. The efficiency of the proposed model for the downlink takes on a Skellam distribution shape which is used for performance modeling.

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