3,282 research outputs found

    Self-organizing Network Optimization via Placement of Additional Nodes

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    Das Hauptforschungsgebiet des Graduiertenkollegs "International Graduate School on Mobile Communication" (GS Mobicom) der Technischen UniversitĂ€t Ilmenau ist die Kommunikation in Katastrophenszenarien. Wegen eines Desasters oder einer Katastrophe können die terrestrischen Elementen der Infrastruktur eines Kommunikationsnetzwerks beschĂ€digt oder komplett zerstört werden. Dennoch spielen verfĂŒgbare Kommunikationsnetze eine sehr wichtige Rolle wĂ€hrend der Rettungsmaßnahmen, besonders fĂŒr die Koordinierung der Rettungstruppen und fĂŒr die Kommunikation zwischen ihren Mitgliedern. Ein solcher Service kann durch ein mobiles Ad-Hoc-Netzwerk (MANET) zur VerfĂŒgung gestellt werden. Ein typisches Problem der MANETs ist Netzwerkpartitionierung, welche zur Isolation von verschiedenen Knotengruppen fĂŒhrt. Eine mögliche Lösung dieses Problems ist die Positionierung von zusĂ€tzlichen Knoten, welche die Verbindung zwischen den isolierten Partitionen wiederherstellen können. Hauptziele dieser Arbeit sind die Recherche und die Entwicklung von Algorithmen und Methoden zur Positionierung der zusĂ€tzlichen Knoten. Der Fokus der Recherche liegt auf Untersuchung der verteilten Algorithmen zur Bestimmung der Positionen fĂŒr die zusĂ€tzlichen Knoten. Die verteilten Algorithmen benutzen nur die Information, welche in einer lokalen Umgebung eines Knotens verfĂŒgbar ist, und dadurch entsteht ein selbstorganisierendes System. Jedoch wird das gesamte Netzwerk hier vor allem innerhalb eines ganz speziellen Szenarios - Katastrophenszenario - betrachtet. In einer solchen Situation kann die Information ĂŒber die Topologie des zu reparierenden Netzwerks im Voraus erfasst werden und soll, natĂŒrlich, fĂŒr die Wiederherstellung mitbenutzt werden. Dank der eventuell verfĂŒgbaren zusĂ€tzlichen Information können die Positionen fĂŒr die zusĂ€tzlichen Knoten genauer ermittelt werden. Die Arbeit umfasst eine Beschreibung, Implementierungsdetails und eine Evaluierung eines selbstorganisierendes Systems, welche die Netzwerkwiederherstellung in beiden Szenarien ermöglicht.The main research area of the International Graduate School on Mobile Communication (GS Mobicom) at Ilmenau University of Technology is communication in disaster scenarios. Due to a disaster or an accident, the network infrastructure can be damaged or even completely destroyed. However, available communication networks play a vital role during the rescue activities especially for the coordination of the rescue teams and for the communication between their members. Such a communication service can be provided by a Mobile Ad-Hoc Network (MANET). One of the typical problems of a MANET is network partitioning, when separate groups of nodes become isolated from each other. One possible solution for this problem is the placement of additional nodes in order to reconstruct the communication links between isolated network partitions. The primary goal of this work is the research and development of algorithms and methods for the placement of additional nodes. The focus of this research lies on the investigation of distributed algorithms for the placement of additional nodes, which use only the information from the nodes’ local environment and thus form a self-organizing system. However, during the usage specifics of the system in a disaster scenario, global information about the topology of the network to be recovered can be known or collected in advance. In this case, it is of course reasonable to use this information in order to calculate the placement positions more precisely. The work provides the description, the implementation details and the evaluation of a self-organizing system which is able to recover from network partitioning in both situations

    Internet of things for disaster management: state-of-the-art and prospects

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    Disastrous events are cordially involved with the momentum of nature. As such mishaps have been showing off own mastery, situations have gone beyond the control of human resistive mechanisms far ago. Fortunately, several technologies are in service to gain affirmative knowledge and analysis of a disaster's occurrence. Recently, Internet of Things (IoT) paradigm has opened a promising door toward catering of multitude problems related to agriculture, industry, security, and medicine due to its attractive features, such as heterogeneity, interoperability, light-weight, and flexibility. This paper surveys existing approaches to encounter the relevant issues with disasters, such as early warning, notification, data analytics, knowledge aggregation, remote monitoring, real-time analytics, and victim localization. Simultaneous interventions with IoT are also given utmost importance while presenting these facts. A comprehensive discussion on the state-of-the-art scenarios to handle disastrous events is presented. Furthermore, IoT-supported protocols and market-ready deployable products are summarized to address these issues. Finally, this survey highlights open challenges and research trends in IoT-enabled disaster management systems. © 2013 IEEE

    Opportunities And Challenges of E-Health and Telemedicine Via Satelite

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    The introduction of Information and Communication Technology (ICT) in the health scenario is instrumental for the development of sustainable services of direct benefit for the European citizen. The setting up of satellite based applications will enhance rapidly the decentralisation and the enrichment of the European territory driving it towards a homogenous environment for healthcare

    Resource Allocation and Performance Optimization in Wireless Networks

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    As wireless networks continue streaking through more aspects of our lives, it is seriously constrained by limited network resources, in terms of time, frequency and power. In order to enhance performance for wireless networks, it is of great importance to allocate resources smartly based on the current network scenarios. The focus of this dissertation is to investigate radio resource management algorithms to optimize performance for different types of wireless networks. Firstly, we investigate a joint optimization problem on relay node placement and route assignment for wireless sensor networks. A heuristic binary integer programming algorithm is proposed to maximize the total number of information packets received at the base station during the network lifetime. We then present an optimization algorithm based on binary integer programming for relay node assignment with the current node locations. Subsequently, a heuristic algorithm is applied to move the relay nodes to the locations iteratively to better serve their associated edge nodes. Secondly, as traditional goal of maximizing the total throughput can result in unbalanced use of network resources, we study a joint problem of power control and channel assignment within a wireless mesh network such that the minimal capacity of all links is maximized. This is essentially a fairness problem. We develop an upper bound for the objective by relaxing the integer variables and linearization. Subsequently, we put forward a heuristic approach to approximate the optimal solution, which tries to increase the minimal capacity of all links via setting tighter constraint and solving a binary integer programming problem. Simulation results show that solutions obtained by this algorithm are very close to the upper bounds obtained via relaxation, thus suggesting that the solution produced by the algorithm is near-optimal. Thirdly, we study the topology control of disaster area wireless networks to facilitate mobile nodes communications by deploying a minimum number of relay nodes dynamically. We first put forward a novel mobility model for mobile nodes that describes the movement of first responders within a large disaster area. Secondly, we formulate the square disk cover problem and propose three algorithms to solve it, including the two-vertex square covering algorithm, the circle covering algorithm and the binary integer programming algorithm. Fourthly, we explore the joint problem of power control and channel assignment to maximize cognitive radio network throughput. It is assumed that an overlaid cognitive radio network (CRN) co-exists with a primary network. We model the opportunistic spectrum access for cognitive radio network and formulate the cross-layer optimization problem under the interference constraints imposed by the existing primary network. A distributed greedy algorithm is proposed to seek for larger network throughput. Cross-layer optimization for CRN is often implemented in centralized manner to avoid co-channel interference. The distributed algorithm coordinates the channel assignment with local channel usage information. Thus the computation complexity is greatly reduced. Finally, we study the network throughput optimization problem for a multi-hop wireless network by considering interference alignment at physical layer. We first transform the problem of dividing a set of links into multiple maximal concurrent link sets to the problem of finding the maximal cliques of a graph. Then each concurrent link set is further divided into one or several interference channel networks, on which interference alignment is implemented to guarantee simultaneous transmission. The network throughput optimization problem is then formulated as a non-convex nonlinear programming problem, which is NP-hard generally. Thus we resort to developing a branch-and-bound framework, which guarantees an achievable performance bound

    Technological Delivery Methods of Community Safety Messages

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    Community safety messages are designed to help educate the public. This project, sponsored by the Australasian Fire Authorities Council was designed to help improve safety message delivery to young people, age 15 to 29, by making use of the newest technologies available. The team used interviews, focus groups, and a survey to gather information about communication technology and safety messages. The findings and the background research enabled the formation of recommendations regarding the future technological delivery methods that will be most effective for the delivery of fire safety messages

    Cyber-Human Systems, Space Technologies, and Threats

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    CYBER-HUMAN SYSTEMS, SPACE TECHNOLOGIES, AND THREATS is our eighth textbook in a series covering the world of UASs / CUAS/ UUVs / SPACE. Other textbooks in our series are Space Systems Emerging Technologies and Operations; Drone Delivery of CBNRECy – DEW Weapons: Emerging Threats of Mini-Weapons of Mass Destruction and Disruption (WMDD); Disruptive Technologies with applications in Airline, Marine, Defense Industries; Unmanned Vehicle Systems & Operations On Air, Sea, Land; Counter Unmanned Aircraft Systems Technologies and Operations; Unmanned Aircraft Systems in the Cyber Domain: Protecting USA’s Advanced Air Assets, 2nd edition; and Unmanned Aircraft Systems (UAS) in the Cyber Domain Protecting USA’s Advanced Air Assets, 1st edition. Our previous seven titles have received considerable global recognition in the field. (Nichols & Carter, 2022) (Nichols, et al., 2021) (Nichols R. K., et al., 2020) (Nichols R. , et al., 2020) (Nichols R. , et al., 2019) (Nichols R. K., 2018) (Nichols R. K., et al., 2022)https://newprairiepress.org/ebooks/1052/thumbnail.jp
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