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  • 201. Drugge, Mikael
    et al.
    Nilsson, Marcus
    Luleå tekniska universitet.
    Synnes, Kåre
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Parnes, Peter
    Eventcasting with a wearable computer2004Ingår i: Proceedings, 24th International Conference on Distributed Computing Systems workshops: 23 - 24 March 2004, Hachioji, Tokyo, Japan / [ed] Nian-Feng Tzeng, Los Alamitos, Calif: IEEE Computer Society Press , 2004, s. 408-413Konferensbidrag (Refereegranskat)
    Abstract [en]

    Traditionally, interaction methods for wearable computers have focused on input to the computer itself, yet little has been done when it comes to allowing interaction with the surrounding environment. Pervasive computing, on the other hand, offers access to computational power from any place all the time, yet most interaction techniques utilize either physical hardware or monitoring of the user in order to receive input. This paper presents a novel form of interaction by which a wearable computer user can interact with and control a pervasive computing environment in a natural and intuitive manner. Using sensors, the user can be allowed to literally "throw" events into the environment as a way of interacting with devices and computers

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  • 202. Drugge, Mikael
    et al.
    Witt, Hendrik
    TZI, Bremen.
    Parnes, Peter
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Synnes, Kåre
    Using the "HotWire'' to study interruptions in wearable computing primary tasks2006Ingår i: Proceedings: Tenth IEEE International Symposium on Wearable Computers, ISWC 2006 : Montreux, Switzerland, October 11 - 14, 2006, Piscataway, NJ: IEEE Communications Society, 2006, s. 37-44Konferensbidrag (Refereegranskat)
    Abstract [en]

    As users of wearable computers are often involved in real-world tasks of critical nature, the management and handling of interruptions is crucial for efficient interaction and task performance. We present a study about the impact that different methods for interruption have on those users, to determine how interruptions should be handled. The study is performed using an apparatus called "HotWire" for simulating primary tasks in a laboratory experiment, while retaining the properties of wearable computers being used in mobile, physical, and practical tasks.

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  • 203.
    Du, Rong
    et al.
    Department of Network and Systems Engineering, KTH Royal Institute of Technology, Stockholm, 10044, Sweden.
    Santi, Paolo
    MIT Senseable City Laboratory, Cambridge, MA 02139 USA and also with the Istituto di Informatica e Telematica del CNR, 56124 Pisa, Italy.
    Xiao, Ming
    Department of Information Science and Engineering, KTH Royal Institute of Technology, Stockholm, 10044, Sweden..
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Fischione, Carlo
    Department of Network and Systems Engineering, KTH Royal Institute of Technology, Stockholm, 10044, Sweden.
    The sensable city: A survey on the deployment and management for smart city monitoring2019Ingår i: IEEE Communications Surveys and Tutorials, E-ISSN 1553-877X, Vol. 21, nr 2, s. 1533-1560Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In last two decades, various monitoring systems have been designed and deployed in urban environments, toward the realization of the so called smart cities. Such systems are based on both dedicated sensor nodes, and ubiquitous but not dedicated devices such as smart phones and vehicles’ sensors. When we design sensor network monitoring systems for smart cities, we have two essential problems: node deployment and sensing management. These design problems are challenging, due to large urban areas to monitor, constrained locations for deployments, and heterogeneous type of sensing devices. There is a vast body of literature from different disciplines that have addressed these challenges. However, we do not have yet a comprehensive understanding and sound design guidelines. This article addresses such a research gap and provides an overview of the theoretical problems we face, and what possible approaches we may use to solve these problems. Specifically, this paper focuses on the problems on both the deployment of the devices (which is the system design/configuration part) and the sensing management of the devices (which is the system running part). We also discuss how to choose the existing algorithms in different type of monitoring applications in smart cities, such as structural health monitoring, water pipeline networks, traffic monitoring. We finally discuss future research opportunities and open challenges for smart city monitoring.

  • 204.
    Du, Wei
    et al.
    Key Laboratory of Advanced Control and Optimization for Chemical Processes, Ministry of Education, East China University of Science and Technology, Shanghai.
    Leung, Sunney Yung Sun
    Institute of Textile and Clothing, The Hong Kong Polytechnic University, Hong Kong.
    Tang, Yang
    Key Laboratory of Advanced Control and Optimization for Chemical Processes, Ministry of Education, East China University of Science and Technology, Shanghai.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Differential Evolution With Event-Triggered Impulsive Control2017Ingår i: IEEE Transactions on Cybernetics, ISSN 2168-2267, E-ISSN 2168-2275, Vol. 7, nr 1, s. 244-257Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Differential evolution (DE) is a simple but powerful evolutionary algorithm, which has been widely and successfully used in various areas. In this paper, an event-triggered impulsive (ETI) control scheme is introduced to improve the performance of DE. Impulsive control (IPC), the concept of which derives from control theory, aims at regulating the states of a network by instantly adjusting the states of a fraction of nodes at certain instants, and these instants are determined by event-triggered mechanism (ETM). By introducing IPC and ETM into DE, we hope to change the search performance of the population in a positive way after revising the positions of some individuals at certain moments. At the end of each generation, the IPC operation is triggered when the update rate of the population declines or equals to zero. In detail, inspired by the concepts of IPC, two types of impulses are presented within the framework of DE in this paper: 1) stabilizing impulses and 2) destabilizing impulses. Stabilizing impulses help the individuals with lower rankings instantly move to a desired state determined by the individuals with better fitness values. Destabilizing impulses randomly alter the positions of inferior individuals within the range of the current population. By means of intelligently modifying the positions of a part of individuals with these two kinds of impulses, both exploitation and exploration abilities of the whole population can be meliorated. In addition, the proposed ETI is flexible to be incorporated into several state-of-the-art DE variants. Experimental results over the IEEE Congress on Evolutionary Computation (CEC) 2014 benchmark functions exhibit that the developed scheme is simple yet effective, which significantly improves the performance of the considered DE algorithms. 

  • 205.
    Du, Wei
    et al.
    Key Laboratory of Advanced Control and Optimization for Chemical Processes, Ministry of Education, East China University of Science and Technology, Shanghai , Institute of Textiles and Clothing, The Hong Kong Polytechnic University.
    Tang, Yang
    Key Laboratory of Advanced Control and Optimization for Chemical Processes, Ministry of Education, East China University of Science and Technology, Shanghai.
    Leung, Sunney Yung Sun
    Institute of Textile and Clothing, The Hong Kong Polytechnic University.
    Tong, Le
    Institute of Textile and Clothing, The Hong Kong Polytechnic University.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Qian, Feng
    Key Laboratory of Advanced Control and Optimization for Chemical Processes, Ministry of Education, East China University of Science and Technology, Shanghai , Institute of Textiles and Clothing, The Hong Kong Polytechnic University.
    Robust Order Scheduling in the Discrete Manufacturing Industry: a Multiobjective Optimization Approach2018Ingår i: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050, Vol. 14, nr 1, s. 253-264, artikel-id 7842622Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Order scheduling is of vital importance in discrete manufacturing industries. This paper takes fashion industry as an example and discusses the robust order scheduling problem in the fashion industry. In the fashion industry, order scheduling focuses on the assignment of production orders to appropriate production lines. In reality, before a new order can be put into production, a series of activities known as preproduction events need to be completed. In addition, in real production process, owing to various uncertainties, the daily production quantity of each order is not always as expected. In this paper, by considering the preproduction events and the uncertainties in the daily production quantity, robust order scheduling problems in the fashion industry are investigated with the aid of a multiobjective evolutionary algorithm called nondominated sorting adaptive differential evolution (NSJADE). The experimental results illustrate that it is of paramount importance to consider preproduction events in order scheduling problems in the fashion industry. We also unveil that the existence of the uncertainties in the daily production quantity heavily affects the order scheduling.

  • 206.
    Duan, Qiang
    et al.
    The Pennsylvania State University, 1600 Woodland Road, Abington, PA 19001, USA.
    Vasilakos, Athanasios V.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Federated selection of network and cloud services for high-performance software-defined cloud computing2016Ingår i: International Journal of High Performance Computing and Networking, ISSN 1740-0562, E-ISSN 1740-0570, Vol. 9, nr 4, s. 316-327Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The crucial role of networking in cloud service provisioning calls for federated selection of network and cloud services in order to guarantee the service performance required by diverse applications. In order to address the new challenges brought in by the software-defined cloud environment (SDCE) to service selection, we develop an approach for performance-based federated selection of network and cloud services in this paper. The main contributions we make in this paper include an abstract profile for network/cloud service capability that is agnostic to service implementations, a general demand profile applicable to diverse applications, an analysis technique for evaluating achievable performance of composite network-cloud services, and a scheme for federated selection of network and cloud services based on performance evaluation. The technique and method developed in this paper enable service selection with a holistic vision across the networking and computing domains, which may greatly facilitate high-performance cloud service provisioning

  • 207. Dudarenko, Natalia
    et al.
    Rana, Juwel
    Synnes, Kåre
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Ranking algorithm by contacts priority for social communication systems2010Ingår i: Smart Spaces and Next Generation Wired/Wireless Networking: Third Conference on Smart Spaces, ruSMART 2010, and 10th International Conference, NEW2AN 2010, St. Petersburg, Russia, August 23-25, 2010. Proceedings / [ed] Sergey Balandin; Roman Dunaytsev; Yevgeni Koucheryavy, Springer Science+Business Media B.V., 2010, s. 38-49Konferensbidrag (Refereegranskat)
    Abstract [en]

    The paper presents the ranking algorithm by contacts with priority application for Social Communication Services. This algorithm makes it Possible to rank contacts in Different Social Communication Services by Their priority for the user, and find a preferable communication tools for everytime contact into the social graph. It Is Proposed to Determine Priorities Of The contacts Using communication history. The ranking algorithm is based on the Markov Chain Theory and Social Strength Calculation Approach. The paper exploits the Opportunities for measuring social strength for the contacts and also "prioritizes communication tools for Simplifying communication. The results are Lindsey village an example.

  • 208.
    Elblaus, Ludvig
    et al.
    KTH Royal Institute of Technology, 100 44, Stockholm, Sweden.
    Unander-Scharin, Åsa
    Luleå tekniska universitet, Institutionen för konst, kommunikation och lärande, Musik och dans.
    Unander-Scharin, Carl
    Karlstad University, 65188 Karlstad, Sweden.
    Uncanny materialities: Digital Strategies for Staging Supernatural Themes Drawn from Medieval Ballads2017Ingår i: Leonardo music journal, ISSN 0961-1215, E-ISSN 1531-4812, Vol. 27, nr 1, s. 62-66Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In the medieval tradition of ballads, a recurring theme is that of transformation. In a staged concert for chamber orchestra, singers and dancers called Varelser och Ballader (Beings and Ballads), we explored this theme using ballads coupled with contemporary poetry and new music. The performance made use of custom-made digital musical instruments, using video analysis and large-scale physical interfaces for transformative purposes. In this article, we describe the piece itself as well as how uncanny qualities of the digital were used to emphasize eerie themes of transformation and deception by the supernatural beings found in the medieval ballads.

  • 209.
    Elf, Stefan
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Application semantics for cost-effective media distribution2003Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Public use of the Internet increases as wideband connections become pervasive and applications suitable for media distribution grow popular. Group collaboration applications have attracted interest during recent years. Wireless connectivity and business applications also furthers a need for reliable communication protocols. Multicast is a driving force for new applications involving one-to-many as well as many-to-many user scenarios like lecturing, discussions, and collaborative work. In some applications guaranteed delivery of every packet is not crucial, while in other this is a requirement. Error handling in reliable protocols can present a substantial challenge already in a homogeneous environment. Including a plethora of end-user terminal types with widely varying resources it becomes even more challenging. Protocols and applications must therefore be able to handle receiver and network link heterogeneity. The thesis addresses some of the challenges facing the applications in this field, related to multicast and unicast alike. Although the obstacles each of them must overcome may differ, there are similarities with regards to possible solutions with respect to error handling or resource allocation. Error handling protocols are proactive or reactive. Proactive protocols transmit redundant information along with the original information, enabling the receivers to repair lost packets without feedback to the sender. Reactive protocols rely either on positive or negative feedback from the receivers in order to establish reliability. According to a definition of semantic reliability the reliability concept can be interpreted in terms of application semantics. It is proposed to view reliable multicast as a special case of semantically reliable multicast and to implement a dynamically configurable transport layer with an error-handling rule set that can be configured from the application or even from the sender in- session. It is also proposed to make use of the application's knowledge of specific semantics to improve on the recovery of lost packets, congestion handling, or resource allocation. The thesis also presents a bandwidth-sharing scheme for video in group collaboration using application semantics in the form of user hints. The presence of such events is made available to all senders via message passing between session members. As information relating to a user's interest in another user is conveyed, the sender may increase its use of resources on the expense of other senders. A scheme is proposed and a prototype implementation and experimental results are presented.

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  • 210.
    Elf, Stefan
    et al.
    Luleå tekniska universitet.
    Parnes, Peter
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    A configurable transport layer as a cure for crying babies2001Ingår i: CSEE'2001: Conference Proceedings, Luleå tekniska universitet, 2001Konferensbidrag (Refereegranskat)
    Abstract [en]

    Group collaboration and media distribution ap- plications have attracted more interest during recent years. With an increasing attention to wireless environments and business applications there is a growing need for reliable multicast communication protocols. There have been mainly two approaches, proactive or re- active, to error handling in reliable multicast. Proactive protocols transmit redundant information along with the original information, enabling the receivers to repair lost packets without the necessity of feedback to the sender. Re- active protocols rely either on positive or negative feedback from the receivers. A case of special interest in relation to wireless connec- tivity is where essentially one receiver on a lossy link even- tually will consume most of the error handling resources. This problem has been addressed by some researchers, e.g. by the use of probabilistic methods. We propose to view reliable multicast as a special case of semantically reliable multicast. We propose to make use of the application’s knowledge of its specific semantics to improve e.g. on the problem with single, lossy, links. We suggest the design of a semantic rule set for the transport layer protocol, which can be configured by the application. Using application semantics would allow the application to relax the reliability requirement at the transport level.

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  • 211.
    Elf, Stefan
    et al.
    Luleå tekniska universitet.
    Parnes, Peter
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    A literature review of recent developments in reliable multicast error handling2001Rapport (Övrigt vetenskapligt)
    Abstract [en]

    As the number of applications directed towards group collaboration and group media dissemination increases, the interest for multicast protocols has also grown during recent years. Several applications have a need for reliability. This is true for the use of shared network editors, shared white-boards, networked games, etc. An increased popularity of media and application distribution over the Internet and the beginning growth of mobile computing with its inherent inhomogeneity and higher loss-rate, will create a demand for security which will increase the need for reliable transmissions. This paper aims to study reliable multicast protocols from an error correction perspective. During recent years, a number of protocols have been proposed. The reliability properties of these lies partly with error correction measures, but to a great extent also with different topological and timing measures which are aimed at boosting protocol efficiency. As it turns out, there are mainly two groups of error correction measures which are used. They can be divided into reactive measures, and proactive. The development in this field of research is very fast. Although a number of studies have already been done, this paper aims to summarise the most recent developments in the area of reliable multicast. This is a literature study and the sources are mainly English-language references from the INSPEC database and the ACM, IEEE, and IEEE Computer Society's digital libraries, essentially from 1997 until 2000.

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  • 212.
    Elf, Stefan
    et al.
    Luleå tekniska universitet.
    Parnes, Peter
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Applying semantic reliability concepts to multicast information messaging in wireless networks2002Ingår i: IRMA Conference Proceedings: Issues & Trends of Information Technology Management in Contemporary Organizations / [ed] M. Khosrowpour, Hershey, Pa: Idea Group Publishing, 2002Konferensbidrag (Refereegranskat)
    Abstract [en]

    Public use of the Internet increases and applications suitable for multicast distribution grow more popular. An increasing percentage of users require wireless connectivity. Multicast solutions must therefore be able to handle receiver and network link heterogeneity. This paper proposes an approach to handle such challenges. According to a definition of semantic reliability, the reliability concept can be interpreted in terms of application semantics. By using semantic reliability traditional reliability constraints can be relaxed. Our approach is to use an application – transport layer communication to implement a dynamically configurable transport layer protocol whose error-handling rule set can be configured from the application or even from the sender in-session. It can also be initiated from the sender when the session starts.

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  • 213.
    Elf, Stefan
    et al.
    Luleå tekniska universitet.
    Scholl, Jeremiah
    Parnes, Peter
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Applying user-behavior to bandwidth adaptations in collaborative workspace applications and video conferencing2003Rapport (Övrigt vetenskapligt)
    Abstract [en]

    A bandwidth-sharing scheme for group video conferencing is presented in this paper. The key features of the scheme are the monitoring of user behavior and message passing, which are used by each client in order to identify and report their interest in other group members. Each video sender operates on the information about other users ' interest in order to adjust the sender's own frame rate, resolution, and ultimately bandwidth consumption in an attempt to satisfy the current interests of the receivers as well as the overall bandwidth constraints of the session. A general framework, an initial prototype, and a bandwidth allocation algorithm are presented together with experimental results. The experiences from the prototype have prompted refinements to the bandwidth-allocation algorithm that will be important for future implementations. We also conclude that the necessary messaging will not add a significant amount of bandwidth.

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  • 214.
    Elf, Stefan
    et al.
    Luleå tekniska universitet.
    Scholl, Jeremiah
    Parnes, Peter
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Schemes for user-interest controlled video bandwidth adaptation in a collaborative workspace environment2004Ingår i: 2004 IEEE International Conference on Multimedia and Expo, Piscataway, NJ: IEEE Communications Society, 2004, s. 197-200Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, bandwidth-sharing schemes, controlled by user-interest, are presented as an approach to efficient use of resources in a collaborative workspace environment. Two schemes for group videoconferencing are presented and evaluated. Monitoring of user-behavior and message passing to adapt video bandwidth allocation to user needs are key features of both schemes, in which each user's client reports interest in other users to enable them to determine their relative importance. Experimental results using a prototype implementation to sample user-behavior show that one scheme is better suited for high, and the other for low bandwidth-limit scenarios. Measurements also show that the message passing does not add a substantial amount of bandwidth.

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  • 215.
    Elkotob, Muslim
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Architectural, service, and performance modeling for an IMS-MBMS-based application2010Ingår i: IEEE International Conference on Communications (ICC), Piscataway, NJ: IEEE Communications Society, 2010Konferensbidrag (Refereegranskat)
    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.

  • 216.
    Elkotob, Muslim
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Autonomic resource management in IEEE 802.11 open access networks2008Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This work is inspired by the autonomic networking paradigm. It investigates the issue of making network resource management mechanisms in the access part of wireless networks self-aware and self-configuring. Open access networks (OAN) have private WLAN cells made available for public use and enable bypassing mobile users to profit from continuous coverage, allowing private and public subscribers to share a common infrastructure. Resources are network parameters, e.g. bandwidth, capacity, that have to be fairly and accurately allocated, distributed, and managed in order to optimize performance and ensure proper and fair operation. Analyzing and exploring existing multimedia session and resource management mechanisms on the wireless part is a crucial step for determining their limitations and shortcomings. A new way of making OANs self-aware is proposed and a self-configuring mechanism which has a competitive advantage in the qualitative sense over already existing mechanisms is designed and developed. The amount of network resources as well as the timing and form of their availability are decisive for enabling service functionality and providing a sufficient quality of service level. Our area of discourse is the "last- mile" part of an 802.11 network; i.e. the part between the access point and the mobile node. In OANs, maintaining and updating rates for different flows used by a single terminal traversing many adjacent APs is a challenge in itself. It is solved by using several key design factors. Monitoring the environment locally and updating the designed information structures leads to network self-awareness. Next, a high-level mechanism that aggregates information from several protocols including CARD (Candidate Access Router Discovery), MIP (Mobile IP), and SIP (Session Initiation Protocol) is defined. It specifies the interactions between the mobile terminal and the access point controller. Then capacity maintenance and rate allocation issues at the two end-points of the last-mile are analyzed. The overhead in OANs required for the launching or reconfiguration of a real-time session can be significantly reduced by a proposed algorithm which performs parameter injection into a multimedia data stream instead of following the classical negotiation path. A solution to change the session characteristics of an application that adapts to varying network conditions was developed, including a QoS solution with SIP and MIP to optimize the session characteristics by taking into account the changed conditions in the network. With this approach, reduced session signaling delay and low jitter values are achieved as implementation results show. The thesis is concluded by considering the general issues: self-aware node architectures, self-configuring resource management.

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  • 217.
    Elkotob, Muslim
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Efficient and systematic network resource management2011Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    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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  • 218. Elkotob, Muslim
    et al.
    Andersson, Karl
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Analysis and measurement of session setup delay and jitter in VoWLAN using composite metrics2008Ingår i: MUM'08 Proceedings: 7th ACM International Conference on Mobile and Ubiquitous Multimedia, December 3 - 5, 2008, Umeå, Sweden / [ed] Arkady Zaslavsky, New York: ACM Digital Library, 2008, s. 190-197Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper we look at the signaling for session mobility using the Session Initiation Protocol (SIP) and the Session Description Protocol (SDP). Bearing in mind that perceived voice quality is sensitive mostly to delay variation (also called jitter), we work on bounding that value for providing a better voice Quality of Service over Wireless LAN (WLAN). For mobility we use a hybrid SIP-MIP stack. The basic idea is to combine the strengths of MIP for doing fast handovers and the strengths of SIP for powerful session adaptation capabilities. Numerical calculation figures as well as real implementation results are provided. It can be observed that the session update cycle during mobility can be modified in such a way that session delay variation bounds achieved are quite low and there are almost no spikes. We use composite performance metrics that we defined in previous work to analyze the correlation between the data patterns for session signaling delay in the classical case and our proposed case to better highlight the achieved performance delta.

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  • 219.
    Elkotob, Muslim
    et al.
    Media Broadcast, TDF Group, Berlin, Germany.
    Andersson, Karl
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Challenges and opportunities in content distribution networks: A case study2012Ingår i: Proceedings of the 2012 IEEE Globecom Workshops (GC Wkshps), IEEE Communications Society, 2012, s. 1021-1026Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper we present some contemporary examples of research-oriented as well as commercial content delivery networks (CDN)s. We discuss how both types of CDNs complement each other in tackling the posed technical and commercial challenges. We also show which performance metrics such as quality of experience (QoE) and time to first byte (TTFB) best capture the dynamics of traffic and services in CDNs. The core of this paper is our proposed network architecture for CDN providers/operators. The architecture combines video multicast optimized trees and cross-layer coordination between the physical DWDM layer (L1) and network layer (L3) for achieving higher efficiency and lower latency values for live streaming and on demand (VoD) video. Due to the pilot implementation of the presented concept being limited in scale, we use simulations in order to perform proof-of-concept on a sufficiently large environment. Results show that there is a strong correlation between the TTFB and QoE metrics with the former taking on values as low as 75 msec in a national 3-tier network.

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  • 220.
    Elkotob, Muslim
    et al.
    Media-Broadcast GmbH.
    Andersson, Karl
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Cross-layer design for improved QoE in content distribution networks2013Ingår i: Journal of IT convergence practice, E-ISSN 2288-0860, Vol. 1, nr 1, s. 37-52Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this article, we present the challenges faced by communication networks in delivering high-quality video content to mobile and stationary devices serving CDN users. Starting with Content Distribution Network types, an overview is given in order to show how this field develops on the research as well as on the commercial side. Research or academic CDNs, new aspects and features are tested to add scalability and functional features to known systems and prototypes. On the other hand, commercial CDNs serve alternatively customers that use broadcasting services. We also show which performance metrics such as quality of experience (QoE) and time to first byte (TTFB) best capture the dynamics of traffic and services in CDNs. The core of this paper is our proposed network architecture for CDN providers/operators. The architecture combines video multicast optimized trees and cross-layer coordination between the physical DWDM layer (L1) and network layer (L3) for achieving higher efficiency and lower latency values for live streaming and on demand (VoD) video. Due to the pilot implementation of the presented concept being limited in scale, we use simulations in order to perform proof-of-concept on a sufficiently large environment. Results show that there is a strong correlation between the TTFB and QoE metrics with the former taking on values as low as 75 msec in a national 3-tier network. Ultimately, our aim is to familiarize readers with the field of CDNs and also to help them see how network research especially in the architectural, protocol design, and cross-layer design help bring applications in this field to a quality level acceptable by a large community of users.

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  • 221.
    Elkotob, Muslim
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    Granlund, Daniel
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Andersson, Karl
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Åhlund, Christer
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Multimedia QoE optimized management using prediction and statistical learning2010Ingår i: 35th Annual IEEE Conference on Local Computer Networks: LCN 2010, Piscataway, NJ: IEEE Communications Society, 2010, s. 328-331Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we present a scheme for flow management with heterogeneous access technologies available indoors and in a campus network such as 3G and Wi-Fi. Statistical learning is used as a key for optimizing a target variable namely video quality of experience (QoE). First we analyze the data using passive measurements to determine relationships between parameters and their impact on the main performance indicator, namely the video QoE value. The derived weights are used for performing prediction in every discrete time interval of our designed autonomic control loop to know approximately the QoE in the next time interval and be able to perform a switch to another access technology if it yields a better QoE level. This user-perspective performance optimization is in line with operator and service provider goals. QoE performance models for slow vehicular and pedestrian speeds for Wi-Fi and 3G are derived and compared as well.

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  • 222.
    Eriksson, Eva
    et al.
    Aarhus University, Denmark. Chalmers University of Technology, Sweden.
    Heath, Carl
    RISE Interactive, Gothenburg.
    Ljungstrand, Peter
    RISE Interactive, Gothenburg.
    Parnes, Peter
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Makerspace in school: Considerations from a large-scale national testbed2018Ingår i: International Journal of Child-Computer Interaction, ISSN 2212-8689, E-ISSN 2212-8697, Vol. 16, s. 9-15Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Digital fabrication and making has received a growing interest in formal and informal learning environments. However, many of these initiatives often start from a grassroots perspective, with little coordination on a national level. This paper illustrates and discusses a study from an ongoing large-scale national testbed in Sweden named Makerspace in schools (Makerskola). The project embodies a series of considerations that arise when a maker approach is applied to a geographically widespread national education context. The results of this study are based on an analysis of the extensive project documentation and first-hand experiences from initiating and running a large-scale national testbed in Sweden, involving more than 30 formal actors and more than one thousand active partners in a national educational setting. The main contribution of this paper is the identification and discussion of five different considerations that have emerged during the project, and include Procurement practices, The teacher and leader perspective, Informing national policy making, Creating equal opportunities, and Progression in digital fabrication.

  • 223.
    Espinilla, Macarena
    et al.
    Department of Computer Science, University of Jaén, Jaén, Spain.
    Medina, Javier
    Department of Computer Science, University of Jaén, Jaén, Spain.
    Hallberg, Josef
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Nugent, Chris
    School of Computing and Mathematics, Ulster University, Coleraine, UK.
    A new approach based on temporal sub-windows for online sensor-based activity recognition2023Ingår i: Journal of Ambient Intelligence and Humanized Computing, ISSN 1868-5137, E-ISSN 1868-5145, Vol. 14, nr 12, s. 15957-15969Artikel i tidskrift (Refereegranskat)
  • 224. Fahlesson, Sarah
    et al.
    Johansson, Dan
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    A case study of cross-platform web application capability2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    This study applies the existing knowledge on native and web applications to a specific case study. We compare the strengths and drawbacks of native applications versus web apps with emphasis on cross-platform functionality. We develop a prototype based on novel web technology (e.g. the emerging HTML5 standard and related frameworks) with the goal of recreating the functionality and graphical properties of an existing native application within the health care area. No changes are made to back-end infrastructure. The prototype is evaluated using cognitive walkthrough, and then we compare the differences of the main types of mobile applications to the results arrived at in this case study. Our beliefs are that the results from this particular case can inform design of cross-platform applications in general.

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  • 225.
    Fan, Kuan
    et al.
    School of computer science and Engineering, Northeastern University, Shenyang, China.
    Bao, Zijian
    School of Cyber Science and Engineering, Wuhan University, Wuhan, China.
    Liu, Mingxi
    School of computer science and Engineering, Northeastern University, Shenyang, China.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap. Computer Science and Technology, Fuzhou University, Fuzhou, China.
    Shi, Wenbo
    School of Computer and Communication Engineering, Northeastern University, Qinhuangdao, China.
    Dredas: Decentralized, reliable and efficient remote outsourced data auditing scheme with blockchain smart contract for industrial IoT2020Ingår i: Future generations computer systems, ISSN 0167-739X, E-ISSN 1872-7115, Vol. 110, s. 665-674Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The development of cloud computing and the Internet of things (IOT) attracts more and more enterprises to outsource the data from their Industrial Internet of things (IIOT) to cloud servers in order to save operating costs and improve efficiency. However, in this environment, protecting the security and privacy of data storage is an important challenge for IIOT and cloud server provider (CSP). Data auditing could allow data owner discover malicious behaviors of CSP which destroy their outsourced data. The public auditing authorizes the trusted third part auditor (TPA) to audit the owner’s outsourced data and frees owner from regular tasks. However, the public auditing using TPA is considered a centralized auditing, and the TPA is assumed totally honest, but it is difficult to find a reliable auditing organization. In this paper, a novel decentralized auditing smart contract in Ethereum is proposed. By replacing the TPA with a designed smart contract, a decentralized auditing scheme (Dredas) is proposed, where anyone can obtain the auditing result from Ethereum without worrying about semi-honest TPA. Compared with traditional auditing, apart from being able to perform traditional auditing functions, Dredas has three important benefits over previous work. First, the random values of challenge are more secure. Dredas chooses the current blockchain nonce as a random seed to prevent any party forging random values. Secondly, in order to achieve a safe, regular, proactive auditing, the protocol writes the auditing rules into the blockchain, and uses the number blocks on the Ethereum as the security timestamp. Finally, data owner, user and CSP must pay some ether for smart contract as deposit. This way not only inhibits the malicious behavior of these three parties, but also makes it more reasonable in real life. We implement Dredas to show that the computation costs are reasonable and efficient.

  • 226.
    Fan, Qingfeng
    et al.
    Laboratoire DAVID, University of Versailles-Saint-Quentin.
    Xiong, Naixue
    School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Department of Business and Computer Science, Southwestern Oklahoma State University.
    Zeitouni, Karine
    Laboratoire DAVID, University of Versailles-Saint-Quentin.
    Wu, Qiongli
    Laboratory Applied Mathematics and Systems, Ecole Centrale de Paris.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Tian, Yu-Chu
    School of Electrical Engineering and Computer Science, Queensland University of Technology.
    Game Balanced Multi-factor Multicast Routing in Sensor Grid Networks2016Ingår i: Information Sciences, ISSN 0020-0255, E-ISSN 1872-6291, Vol. 367-368, s. 550-572Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In increasingly important sensor grid networks, multicast routing is widely used in date aggregation and distributed query processing. It requires multicast trees for efficient data transmissions. However, sensor nodes in such networks typically have limited resources and computing power. Efforts have been made to consider the space, energy and data factors separately to optimize the network performance. Considering these factors simultaneously, this paper presents a game balance based multi-factor multicast routing approach for sensor grid networks. It integrates the three factors into a unified model through a linear combination. The model is standardized and then solved theoretically by using the concept of game balance from game theory. The solution gives Nash equilibrium, implying a well balanced result for all the three factors. The theoretic results are implemented in algorithms for cluster formation, cluster core selection, cluster tree construction, and multicast routing. Extensive simulation experiments show that the presented approach gives mostly better overall performance than benchmark methods.

  • 227.
    Fan, Ye
    et al.
    Department of Information and Communication Engineering, Xi’an Jiaotong University, Xi’an, China.
    Liao, Xuewen
    Department of Information and Communication Engineering, Xi’an Jiaotong University, Xi’an, China.
    Vasilakos, Athanasios V.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Physical Layer Security Based on Interference Alignment in K-User MIMO Y Wiretap Channels2017Ingår i: IEEE Access, E-ISSN 2169-3536, Vol. 5, s. 5747-5759Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper studies the secure degree of freedom (SDOF) of the multiway relay wiretap system K -user MIMO Y wiretap channel, where each legitimate user equipped with M antennas intends to convey independent signals via an intermediate relay with N antennas. There exists an eavesdropper which is equipped with Neantennas close to the legitimate users. In order to eliminate the multiuser interference and keep the system security, interference alignment is mainly utilized in the proposed broadcast wiretap channel (BWC) and multi-access BWC (MBWC), and cooperative jamming is adopted as a supplementary approach in the MBWC model. The general feasibility conditions of the interference alignment are deduced asM≥K−1,2M>N and N≥((K(K−1))/2) . In the BWC model, we have deduced the secure degrees of freedom (SDOF) asKmin{M,N}−min{Ne,K(K−1)/2} , which is always a positive value. While in the MBWC model, the SDOF is given by Kmin{M,N} . Finally, since the relay transmits the synthesized signals of the legal signal and the jamming signal in the MBWC model, we propose a power allocation scheme to maximize the secrecy rate. Simulation results demonstrate that our proposed power allocation scheme can improve secrecy rate under various antenna configurations.

  • 228.
    Fejzo, Orsola
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Zaslavsky, Arkady
    Deakin University, Melbourne, Australia. ITMO University, Saint Petersburg, Russia.
    Saguna, Saguna
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Mitra, Karan
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Proactive Context-Aware IoT-Enabled Waste Management2019Ingår i: Proceeings of the 19th International Conference on Next Generation Wired/Wireless Advanced Networks and System, Springer, 2019, s. 3-15Konferensbidrag (Refereegranskat)
    Abstract [en]

    Exploiting future opportunities and avoiding problematic upcoming events is the main characteristic of a proactively adapting system, leading to several benefits such as uninterrupted and efficient services. In the era when IoT applications are a tangible part of our reality, with interconnected devices almost everywhere, there is potential to leverage the diversity and amount of their generated data in order to act and take proactive decisions in several use cases, smart waste management as such. Our work focuses in devising a system for proactive adaptation of behavior, named ProAdaWM. We propose a reasoning model and system architecture that handles waste collection disruptions due to severe weather in a sustainable and efficient way using decision theory concepts. The proposed approach is validated by implementing a system prototype and conducting a case study.

  • 229.
    Femminella, Marco
    et al.
    Department of Engineering, University of Perugia CNIT RU.
    Reali, Gianluca
    Department of Engineering, University of Perugia CNIT RU.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    A Molecular Communications Model for Drug Delivery2015Ingår i: IEEE Transactions on Nanobioscience, ISSN 1536-1241, E-ISSN 1558-2639, Vol. 14, nr 8, s. 935-945Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper considers the scenario of a targeted drug delivery system, which consists of deploying a number of biological nanomachines close to a biological target (e.g., a tumor), able to deliver drug molecules in the diseased area. Suitably located transmitters are designed to release a continuous flow of drug molecules in the surrounding environment, where they diffuse and reach the target. These molecules are received when they chemically react with compliant receptors deployed on the receiver surface. In these conditions, if the release rate is relatively high and the drug absorption time is significant, congestion may happen, essentially at the receiver site. This phenomenon limits the drug absorption rate and makes the signal transmission ineffective, with an undesired diffusion of drug molecules elsewhere in the body. The original contribution of this paper consists of a theoretical analysis of the causes of congestion in diffusion-based molecular communications. For this purpose, it is proposed a reception model consisting of a set of pure loss queuing systems. The proposed model exhibits an excellent agreement with the results of a simulation campaign made by using the Biological and Nano-Scale communication simulator version 2 (BiNS2), a well-known simulator for molecular communications, whose reliability has been assessed through in vitro experiments. The obtained results can be used in rate control algorithms to optimally determine the optimal release rate of molecules in drug delivery applications

  • 230.
    Floeck, Martin
    et al.
    NEC Europe Ltd.
    Schülke, Anett
    NEC Europe Ltd.
    Schmidt, Mischa
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap. NEC Europe Ltd.
    Hernandez, Jose Luis
    NEC Europe Ltd.
    Martin Toral, Susana
    CARTIF Centro Tecnólogico.
    Valmaseda, Cesar
    CARTIF Centro Tecnólogico.
    A novel approach towards tight integration of existing building automation control systems for improved energy management and resource utilisation2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper presents interim results of the currently ongoing "Building as a Service" (BaaS) EU project. The BaaS project aims at optimising energy performance of non-residential buildings, e.g. schools, universities, hotels, shopping centres, or sports facilities.

    An ICT platform is being developed that integrates IT systems that already exist in infrastructure assets with new IT components delivering novel functionalities extending the performance assessment of buildings. The former include building management systems (BMSs), access control systems, or systems providing weather data. The latter are mostly concerned with the assessment, prediction, and optimisation (APO) of energy usage and modelling. The IT infrastructure systems and APO services are linked by an integration middleware. The main features of this middleware are standardised interfaces via which all communication between the components of the system is routed. Functioning and characteristics of the middleware and its interfaces will be explained in the present paper.

  • 231.
    Floeck, Martin
    et al.
    NEC Europe Ltd..
    Schülke, Anett
    NEC Europe Ltd..
    Schmidt, Mischa
    NEC Europe Ltd..
    Hernández, José Luís Pérez
    CARTIF Centro Tecnólogico, 47151 Boecillo (Valladolid).
    Toral, Susana Martín
    CARTIF Centro Tecnólogico, 47151 Boecillo (Valladolid).
    Valmaseda, César
    CARTIF Centro Tecnólogico, 47151 Boecillo (Valladolid).
    Tight integration of existing building automation control systems for improved energy management and resource utilisation2013Ingår i: CESB 2013 PRAGUE: Central Europe Towards Sustainable Building 2013 : Sustainable Building and Refurbishment for Next Generations, Prague, Czech Republic, 26 - 28 June 2013, Prague: Czech Technical University in Prague , 2013, s. 51-54Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper presents interim results of the currently ongoing Building as a Service (BaaS) EU project. The BaaS project aims at optimising energy performance of non-residential buildings, e.g. schools, universities, hotels, shopping centres, or sports facilities. An ICT platform is being developed that integrates IT systems that already exist in infrastructure assets with new IT components delivering novel functionalities extending the performance assessment of buildings. The former include building management systems (BMSs), access control systems, or systems providing weather data. The latter are mostly concerned with the assessment, prediction, and optimisation (APO) of energy usage and modelling. The IT infrastructure systems and APO services are linked by an integration middleware. The main features of this middleware are standardised interfaces via which all communication between the components of the system is routed. Functioning and characteristics of the middleware and its interfaces will be explained in the present paper

  • 232.
    Fong, Simon
    et al.
    Department of Computer and Information Science, University of Macau.
    Han, Dong
    Department of Computer and Information Science, University of Macau.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Comparative study of incremental learning algorithms in multidimensional outlier detection on data stream2015Ingår i: Improving Knowledge Discovery through the Integration of Data Mining Techniques, Hershey, PA: IGI Global, 2015, s. 54-73Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Multi-dimensional outlier detection (MOD) over data streams is one of the most significant data stream mining techniques. When multivariate data are streaming in high speed, outliers are to be detected efficiently and accurately. Conventional outlier detection method is based on observing the full dataset and its statistical distribution. The data is assumed stationary. However, this conventional method has an inherent limitation-it always assumes the availability of the entire dataset. In modern applications, especially those that operate in the real time environment, the data arrive in the form of live data feed; they are dynamic and ever evolving in terms of their statistical distribution and concepts. Outlier detection should no longer be done in batches, but in incremental manner. In this chapter, we investigate into this important concept of MOD. In particular, we evaluate the effectiveness of a collection of incremental learning algorithms which are the underlying pattern recognition mechanisms for MOD. Specifically, we combine incremental learning algorithms into three types of MOD-Global Analysis, Cumulative Analysis and Lightweight Analysis with Sliding Window. Different classification algorithms are put under test for performance comparison

  • 233.
    Fong, Simon
    et al.
    Department of Computer and Information Science, University of Macau.
    Ji, Jinyan
    Department of Computer and Information Science, Faculty of Science and Technology, University of Macau.
    Gong, Xueyuan
    Department of Computer and Information Science, University of Macau.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Advances of applying metaheuristics to data mining techniques2015Ingår i: Improving Knowledge Discovery through the Integration of Data Mining Techniques, Hershey, PA: IGI Global, 2015, s. 75-103Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Metaheuristics have lately gained popularity among researchers. Their underlying designs are inspired by biological entities and their behaviors, e.g. schools of fish, colonies of insects, and other land animals etc. They have been used successfully in optimization applications ranging from financial modeling, image processing, resource allocations, job scheduling to bioinformatics. In particular, metaheuristics have been proven in many combinatorial optimization problems. So that it is not necessary to attempt all possible candidate solutions to a problem via exhaustive enumeration and evaluation which is computationally intractable. The aim of this paper is to highlight some recent research related to metaheuristics and to discuss how they can enhance the efficacy of data mining algorithms. An upmost challenge in Data Mining is combinatorial optimization that, often lead to performance degradation and scalability issues. Two case studies are presented, where metaheuristics improve the accuracy of classification and clustering by avoiding local optima.

  • 234.
    Fong, Simon
    et al.
    Department of Computer and Information Science, University of Macau.
    Wong, Raymond K.
    School of Computer Science and Engineering, University of New South Wales, Sydney.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Accelerated PSO Swarm Search Feature Selection for Data Stream Mining Big Data2016Ingår i: IEEE Transactions on Services Computing, E-ISSN 1939-1374, Vol. 9, nr 1, s. 33-45Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Big Data though it is a hype up-springing many technical challenges that confront both academic research communities and commercial IT deployment, the root sources of Big Data are founded on data streams and the curse of dimensionality. It is generally known that data which are sourced from data streams accumulate continuously making traditional batch-based model induction algorithms infeasible for real-time data mining. Feature selection has been popularly used to lighten the processing load in inducing a data mining model. However, when it comes to mining over high dimensional data the search space from which an optimal feature subset is derived grows exponentially in size, leading to an intractable demand in computation. In order to tackle this problem which is mainly based on the high-dimensionality and streaming format of data feeds in Big Data, a novel lightweight feature selection is proposed. The feature selection is designed particularly for mining streaming data on the fly, by using accelerated particle swarm optimization (APSO) type of swarm search that achieves enhanced analytical accuracy within reasonable processing time. In this paper, a collection of Big Data with exceptionally large degree of dimensionality are put under test of our new feature selection algorithm for performance evaluation.

  • 235.
    Fu, Zhangjie
    et al.
    School of Computer and Software, Nanjing University of Information Science and Technology, Nanjing 210044, China.
    Huang, Fengxiao
    School of Computer and Software, Nanjing University of Information Science and Technology, Nanjing 210044, China.
    Sun, Xingming
    School of Computer and Software, Nanjing University of Information Science and Technology, Nanjing 210044, China.
    Vasilakos, Athanasios V.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Yang, Ching-Nung
    Department of Computer Science and Information Engineering, National Dong Hwa University, Hualien County 974, Taiwan.
    Enabling Semantic Search based on Conceptual Graphs over Encrypted Outsourced Data2019Ingår i: IEEE Transactions on Services Computing, E-ISSN 1939-1374, Vol. 12, nr 5, s. 813-823Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Currently, searchable encryption is a hot topic in the field of cloud computing. The existing achievements are mainly focused on keyword-based search schemes, and almost all of them depend on predefined keywords extracted in the phases of index construction and query. However, keyword-based search schemes ignore the semantic representation information of users’ retrieval and cannot completely match users’ search intention. Therefore, how to design a content-based search scheme and make semantic search more effective and context-aware is a difficult challenge. In this paper, for the first time, we define and solve the problems of semantic search based on conceptual graphs(CGs) over encrypted outsourced data in clouding computing (SSCG).We firstly employ the efficient measure of ”sentence scoring” in text summarization and Tregex to extract the most important and simplified topic sentences from documents. We then convert these simplified sentences into CGs. To perform quantitative calculation of CGs, we design a new method that can map CGs to vectors. Next, we rank the returned results based on ”text summarization score”. Furthermore, we propose a basic idea for SSCG and give a significantly improved scheme to satisfy the security guarantee of searchable symmetric encryption (SSE). Finally, we choose a real-world dataset – ie., the CNN dataset to test our scheme. The results obtained from the experiment show the effectiveness of our proposed scheme.

  • 236.
    Følstad, Asbjørn
    et al.
    SINTEF, Oslo.
    Brandtzæg, Petter Bae
    SINTEF, Oslo.
    Gulliksen, Jan
    Uppsala universitet.
    Börjeson, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, CDT.
    Näkki, Pirjo
    VTT.
    Towards a manifesto for living lab co-creation2009Ingår i: Human-Computer Interaction - INTERACT 2009: 12th IFIP TC 13 International Conference, Uppsala, Sweden, August 24-28, 2009, Proceedings / [ed] Tom Gross, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2009, Vol. 2, s. 979-980Konferensbidrag (Refereegranskat)
    Abstract [en]

    There is a growing interest in Living Labs for innovation and development in the field of information and communication technology. In particular there seem to be a tendency that current Living Labs aim to involve users for co-creative purposes. However, the current literature on Living Lab co-creation is severely limited. Therefore an Interact workshop is arranged as a first step towards a manifesto for Living Lab co-creation.

  • 237.
    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 tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Adaptive clutter-aware visualization for mobile data stream mining2010Ingår i: 22nd International Conference on Tools with Artificial Intelligence: proceedings : 27-29 October 2010, Arras, France, Los Alamitos, Calif: IEEE Communications Society, 2010, s. 304-311Konferensbidrag (Refereegranskat)
    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.

  • 238.
    Gan, Wensheng
    et al.
    College of Cyber Security/College of Information Science and Technology, Jinan University, Guangzhou 510632 Chin.
    Lin, Jerry Chun-Wei
    Western Norway University of Applied Sciences 5063, Bergen Norway.
    Chao, Han-Chieh
    National Dong Hwa University, Hualien 97401 Taiwan.
    Vasilakos, Athanasios V.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Yu, Philip S.
    University of Illinois at Chicago, Chicago, IL 60607 USA.
    Utility-Driven Data Analytics on Uncertain Data2020Ingår i: IEEE Systems Journal, ISSN 1932-8184, E-ISSN 1937-9234, Vol. 14, nr 3, s. 4442-4453Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Modern Internet of Things (IoT) applications generate massive amounts of data, much of them in the form of objects/items of readings, events, and log entries. Specifically, most of the objects in these IoT data contain rich embedded information (e.g., frequency and uncertainty) and different levels of importance (e.g., unit risk/utility of items, interestingness, cost, or weight). Many existing approaches in data mining and analytics have limitations, such as only the binary attribute is considered within a transaction, as well as all the objects/items having equal weights or importance. To solve these drawbacks, a novel utility-driven data analytics algorithm named HUPNU is presented in this article. As a general utility-driven uncertain data mining model, HUPNU can extract High-Utility patterns by considering both Positive and Negative unit utilities from Uncertain data. The qualified high-utility patterns can be effectively discovered for intrusion detection, risk prediction, manufacturing management, and decision-making, among others. By using the developed vertical Probability-Utility list with the positive and negative utilities structure, as well as several effective pruning strategies, experiments showed that the developed HUPNU approach with the pruning strategies performed great in mining the qualified patterns efficiently and effectively.

  • 239.
    Gao, Deyun
    et al.
    School of Electronic and Information Engineering, Beijing Jiaotong University.
    Rao, Ying
    China Academy of Electronics and Information Technology, Beijing.
    Foh, Huang Chen
    5GIC, Institute for Communication Systems, Department of Electrical and Electronic Engineering, University of Surrey.
    Zhang, Hongke
    School of Electronic and Information Engineering, Beijing Jiaotong University.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    PMNDN: Proxy Based Mobility Support Approach in Mobile NDN Environment2017Ingår i: IEEE Transactions on Network and Service Management, ISSN 1932-4537, E-ISSN 1932-4537, Vol. 14, nr 1, s. 191-203Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we study the source mobility problem that exists in the current named data networking (NDN) architecture and propose a proxy-based mobility support approach named PMNDN to overcome the problem. PMNDN proposes using a proxy to efficiently manage source mobility. Besides, functionalities of the NDN access routers are extended to track the mobility status of a source and signal Proxy about a handoff event. With this design, a mobile source does not need to participate in handoff signaling which reduces the consumption of limited wireless bandwidth. PMNDN also features an ID that is structurally similar to the content name so that routing scalability of NDN architecture is maintained and addressing efficiency of Interest packets is improved. We illustrate the performance advantages of our proposed solution by comparing the handoff performance of the mobility support approaches with that in NDN architecture and current Internet architecture via analytical and simulation investigation. We show that PMNDN offers lower handoff cost, shorter handoff latency, and less packet losses during the handoff process

  • 240.
    Georgakopoulos, Dimitrios
    et al.
    CSIRO, Australia.
    Ranjan, Rajiv
    CSIRO, Australia.
    Mitra, Karan
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Zhou, Xiangmin
    CSIRO, Australia.
    MediaWise: designing a smart media cloud2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    The MediaWise project aims to expand the scope ofexisting media delivery systems with novel cloud, personalizationand collaboration capabilities that can serve the needs of moreusers, communities, and businesses. The project develops aMediaWise Cloud platform that supports do-it-yourself creation,search, management, and consumption of multimedia content.The MediaWise Cloud supports pay-as-you-go models andelasticity that are similar to those offered by commerciallyavailable cloud services. However, unlike existing commercialCDN services providers such as Limelight Networks and Akamaithe MediaWise Cloud require no ownerships of computinginfrastructure and instead rely on the public Internet and publiccloud services (e.g., commercial cloud storage to store its content).In addition to integrating such public cloud services into a publiccloud-based Content Delivery Network, the MediaWise Cloudalso provides advanced Quality of Service (QoS) management asrequired for the delivery of streamed and interactive highresolution multimedia content. In this paper, we give a briefoverview of MediaWise Cloud architecture and present acomprehensive discussion on research objectives related to itsservice components. Finally, we also compare the featuressupported by the existing CDN services against the envisionedobjectives of MediaWise Cloud.

  • 241.
    Ghulam, Muhammad
    et al.
    Department of Computer Engineering, College of Computer and Information Sciences, King Saud University, Riyadh .
    Alhamid, Mohammed F
    Department of Software Engineering, College of Computer and Information Sciences, King Saud University, Riyadh .
    Hossain, M. Shamim
    Department of Software Engineering, College of Computer and Information Sciences, King Saud University, Riyadh .
    Almogren, Ahmad S.
    Department of Computer Science, College of Computer and Information Sciences, King Saud University, Riyadh .
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Enhanced Living by Assessing Voice Pathology Using a Co-Occurrence Matrix2017Ingår i: Sensors, E-ISSN 1424-8220, Vol. 17, nr 2, artikel-id 267Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    large number of the population around the world suffers from various disabilities. Disabilities affect not only children but also adults of different professions. Smart technology can assist the disabled population and lead to a comfortable life in an enhanced living environment (ELE). In this paper, we propose an effective voice pathology assessment system that works in a smart home framework. The proposed system takes input from various sensors, and processes the acquired voice signals and electroglottography (EGG) signals. Co-occurrence matrices in different directions and neighborhoods from the spectrograms of these signals were obtained. Several features such as energy, entropy, contrast, and homogeneity from these matrices were calculated and fed into a Gaussian mixture model-based classifier. Experiments were performed with a publicly available database, namely, the Saarbrucken voice database. The results demonstrate the feasibility of the proposed system in light of its high accuracy and speed. The proposed system can be extended to assess other disabilities in an ELE.

  • 242.
    Gong, Xueyuan
    et al.
    Department of Computer and Information Science, University of Macau.
    Fong, Simon
    Department of Computer and Information Science, University of Macau.
    Si, Yainwhar
    Department of Computer and Information Science, University of Macau.
    Biuk-Agha, Robert P.
    School of Computer Science and Engineering, University of New South Wales, Sydney.
    Wong, Raymond K.
    School of Computer Science and Engineering, University of New South Wales, Sydney.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Normalized Cross-Match: Pattern Discovery Algorithm from Biofeedback Signals2016Ingår i: Trends and Applications in Knowledge Discovery and Data Mining: PAKDD 2016 Workshops, BDM, MLSDA, PACC, WDMBF, Auckland, New Zealand, April 19, 2016, Revised Selected Papers, Encyclopedia of Global Archaeology/Springer Verlag, 2016, s. 169-180Konferensbidrag (Refereegranskat)
    Abstract [en]

    Biofeedback signals are important elements in critical care applications, such as monitoring ECG data of a patient, discovering patterns from large amount of ECG data sets, detecting outliers from ECG data, etc. Because the signal data update continuously and the sampling rates may be different, time-series data stream is harder to be dealt with compared to traditional historical time-series data. For the pattern discovery problem on time-series streams, Toyoda proposed the CrossMatch (CM) approach to discover the patterns between two time-series data streams (sequences), which requires only O(n) time per data update, where n is the length of one sequence. CM, however, does not support normalization, which is required for some kinds of sequences (e.g. EEG data, ECG data). Therefore, we propose a normalized-CrossMatch approach (NCM) that extends CM to enforce normalization while maintaining the same performance capabilities

  • 243.
    Gong, Yueyuan
    et al.
    Department of Computer and Information Science, University of Macau.
    Fong, Simon
    Department of Computer and Information Science, University of Macau.
    Wong, Raymond K.
    School of Computer Science and Engineering, University of New South Wales, Sydney.
    Mohammed, Sabah
    Department of Computer Science, Lakehead University, Thunder Bay.
    Faidhi, Jinan
    Department of Computer Science, Lakehead University, Thunder Bay.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Discovering sub-patterns from time series using a normalized cross-match algorithm2016Ingår i: Journal of Supercomputing, ISSN 0920-8542, E-ISSN 1573-0484, Vol. 72, nr 10, s. 3850-3867Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Time series data stream mining has attracted considerable research interest in recent years. Pattern discovery is a challenging problem in time series data stream mining. Because the data update continuously and the sampling rates may be different, dynamic time warping (DTW)-based approaches are used to solve the pattern discovery problem in time series data streams. However, the naive form of the DTW-based approach is computationally expensive. Therefore, Toyoda proposed the CrossMatch (CM) approach to discover the patterns between two time series data streams (sequences), which requires only O(n) time per data update, where n is the length of one sequence. CM, however, does not support normalization, which is required for some kinds of sequences (e.g. stock prices, ECG data). Therefore, we propose a normalized-CrossMatch approach that extends CM to enforce normalization while maintaining the same performance capabilities.

  • 244.
    Granlund, Daniel
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    On Mobility Solutions in Heterogeneous Networking Environments2015Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Mobility support for users and devices, such as sensors, connecting to the Internet is a continuously growing trend. Different types of wireless networking technologies like WiFi, LTE, and ZigBee are available, creating a heterogeneous wireless networking environment. In general, the technology, ranging from network equipment to communications protocols, available today, tends to be designed with limited exibility when it comes to supporting heterogeneity. Proprietary technology and highly optimized mechanisms limit the potential use of networking infrastructure for multiple purposes. Supporting mobility for wireless devices between different networking technologies and administrative domains requires secure and scalable mobility management solutions. Current research in the field of mobility management and security in heterogeneous networking environment tends to handle mobility management performance, such as communications characteristics, and security related aspects as separate, and more or less mutually exclusive. The work presented in this thesis serves to challenge this trade-off and proposes solutions that seeks to brigde the gap between the two areas. This thesis proposes using an Authentication, Authorization and Accounting (AAA) system based on the RADIUS AAA protocol that enables a common AAA infrastructure to operate in a heterogeneous networking environment, and that enables a hierarchical interconnection structure between service providers. The proposed AAA architecture offers a highly scalable AAA infrastructure with access technology independent support for user and device authentication as well as mobility on a global scale. Further, to support handoffs between networks, a set of methods for facilitating improved handoff decisions for intra- and inter-operator mobility in heterogeneous networks are presented. These methods rely on metrics that include indicators on network load conditions to improve service stability and decrease application down time during handoff.Results show that the proposed AAA infrastructure can be built to scale in order to support a very large number of entities, more than 1000 user or device authentications per second, using industry standard hardware. Further, an AAA architecture compatible sensor authentication protocol is proposed, implemented, and validated that supports sensor mobility and reduces power consumption, on wireless sensor nodes, with 33% compared to state-of-the-art protocols by reducing CPU and communications overhead. Using the proposed mechanism for facilitating handos in wireless sensor networks, a reduction of 44% in packet loss is achived during a mobility session compared to a traditional solution.

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  • 245.
    Granlund, Daniel
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Secure and scalable roaming support in heterogeneous access networks2011Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    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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  • 246.
    Granlund, Daniel
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Andersson, Karl
    Brännström, Robert
    Estimating network performance using low impact probing2008Ingår i: Proceedings of the 1st Workshop on Wireless Broadband Access for Communities and Rural Developing Regions: WIRELESS4D '08 / [ed] Andreas J. Kassler, 2008Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper focuses on estimating network performance in order to make proper decisions regarding data flow path selection. The purpose is to estimate the available bandwidth without flooding the network with traffic like traditional bandwidth measurement tools such as Iperf. By using small datagrams to probe the network rather than flooding the link, delay and jitter can be measured and used for calculations. The idea is to use statistical information about the delay to make an acceptable estimation of the available bandwidth. Lntransform of delay and standard deviation of delay were found to be the most accurate parameters and provide the best correlation. Also, some network technologies have a significant difference in up and downlink delay. This can pose a problem when estimating the link performance. Therefore this paper also proposes a solution to handle measurements in asymmetrical links.

  • 247.
    Granlund, Daniel
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Andersson, Karl
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Elkotob, Muslim
    Åhlund, Christer
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    A uniform AAA handling scheme for heterogeneous networking environments2009Ingår i: 2009 IEEE 34th Conference on Local Computer Networks: LCN 2009 ; Zurich, Switzerland, 20 - 23 October 2009 ;, Piscataway, NJ: IEEE Communications Society, 2009, s. 683-687Konferensbidrag (Refereegranskat)
    Abstract [en]

    Starting with an efficient mobility management scheme for heterogeneous wireless networks, this paper proposes a solution for AAA handling using a common database for storing user information. Regardless of the access technology selected, user@realm identities are used for authentication, authorization, and accounting. In particular, a new function is introduced in which port-based network access control is used in combination with dynamic host configuration protocol mechanisms for IP address allocation. This way, PPP-based and Ethernet-based access technologies are handled uniformly.Advantages with the proposed solution include: using only standardized mechanisms in the mobile node, as well as in the access networks. Only an additional plug-in in the AAA server (located in the access networks) needs to be deployed.The proposed AAA architecture has been implemented and evaluated in a live experimental environment. Results show authentication and authorization to perform efficiently and seamlessly.

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  • 248.
    Granlund, Daniel
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Brännström, Robert
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Smart city: the smart sewerage2012Ingår i: 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, s. 856-859Konferensbidrag (Refereegranskat)
    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.

  • 249. Granlund, Daniel
    et al.
    Gylling, Arne
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, CDT.
    Åhlund, Christer
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Osipov, Evgeny
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Brännström, Robert
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Jacquier, Anna
    Elkotob, Muslim
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, CDT.
    Åhl, Anneli
    Project: BASICNET2008Övrigt (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    Broadband Access Services In Converging NETworks

  • 250.
    Granlund, Daniel
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Holmlund, Patrik
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Åhlund, Christer
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Opportunistic Mobility Support for Resource Constrained Sensor Devices in Smart Cities2015Ingår i: Sensors, E-ISSN 1424-8220, Vol. 15, nr 3, s. 5112-5135Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A multitude of wireless sensor devices and technologies are being developed and deployed in cities all over the world. Sensor applications in city environments may include highly mobile installations that span large areas which necessitates sensor mobility support. This paper presents and validates two mechanisms for supporting sensor mobility between different administrative domains. Firstly, EAP-Swift, an Extensible Authentication Protocol (EAP)-based sensor authentication protocol is proposed that enables light-weight sensor authentication and key generation. Secondly, a mechanism for handoffs between wireless sensor gateways is proposed. We validate both mechanisms in a real-life study that was conducted in a smart city environment with several fixed sensors and moving gateways. We conduct similar experiments in an industry-based anechoic Long Term Evolution (LTE) chamber with an ideal radio environment. Further, we validate our results collected from the smart city environment against the results produced under ideal conditions to establish best and real-life case scenarios. Our results clearly validate that our proposed mechanisms can facilitate efficient sensor authentication and handoffs while sensors are roaming in a smart city environment.

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