We present the design, implementation, and experimental evaluation of a wireless sensor network for near real-time structural health monitoring. We use simple custom-built gages to unequivocally detect cracks in criti...
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We present the design, implementation, and experimental evaluation of a wireless sensor network for near real-time structural health monitoring. We use simple custom-built gages to unequivocally detect cracks in critical structural elements. the main data reports have a low data rate and are naturally resilient to loss. We show how a variety of low-cost, off-the-shelf data acquisition/communication devices can be used to support remote monitoring by a control center. the heterogeneous hardware is accommodated by the use of open technology standards, and a software architecture that is portable, modular, and highly configurable. We present an experimental evaluation of our structural assessment network, using a full-scale three-story reinforced concrete building, subjected to lateral forces emulating forces induced by earthquakes. Our results show that a set of 12 strategically positioned sensors on the three floors achieved a zero false-alarm rate, in the sense that each reported breakage can be traced to cracks exceeding the specified total width, and a 100% detection rate for cracks that are covered by a sensor.
this paper studies the scaling laws of the data gathering capacity of large scale multihop wireless networks. Unlike the data communication paradigms studied in previous research, for example, the many-to-many, many-t...
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this paper studies the scaling laws of the data gathering capacity of large scale multihop wireless networks. Unlike the data communication paradigms studied in previous research, for example, the many-to-many, many-to-one, broadcast, and multicast paradigms, the data gathering capacity concerns the per source node throughput in a network where a subset of nodes send data to some designated destinations while other nodes serve as relays. this some-to-some communication paradigm is commonplace in many wireless networks, for example, wireless mesh networks and wireless sensor networks, and in some cases perhaps more prevalent than the other paradigms. We first derive the upper and constructive lower bounds for the data gathering capacity, and then examine their design and performance implications. Our results show that the data gathering capacity is constrained by different factors in several different scaling regimes of the number of source and destination nodes, exhibiting distinct scaling laws in those regimes. this work fills a gap in our understanding of the capacity of various communication paradigms, and can lead to better network planning and performance for data gathering wireless network applications.
distributed workflow management systems are increasingly gaining momentum due to the emergence of virtual and distributed organizations, as well as cross-organizational workflows. this paper presents an effective deve...
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distributed workflow management systems are increasingly gaining momentum due to the emergence of virtual and distributed organizations, as well as cross-organizational workflows. this paper presents an effective development process for a distributed workflow management system (WKFMS) which is utilized to automate the management processes related to computer and peripheral repair requests in the Faculty of Engineering and Technology (FET) at the University of Jordan. First, the paper explores the reasoning and motivation behind the choice of the management processes involved in the WKFMS. Phases of the development process that is based on the rapid prototyping paradigm are then described. Particular focus is given to the modeling of business scenarios using the Model-View-Control (MVC) architecture. the distributed network layout and system security measures are also investigated. Reduction of manual human intervention in the decision process is achieved through the implementation of a neuro-fuzzy computational intelligence processor to automate the major decision making process of tasks distribution. It is shown that the application of the proposed development process helped in reducing the overall system development time and effort. the successful deployment and functional testing of the developed industrial prototype has proved that it works smoothly according to the desired features.
this work proposes an algorithm to perform the resource allocation in the uplink of an ieee802.16 standard-based system. the approach is valid for point to multi-point (PMP) and also for tree-deployed mesh networks, a...
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this work proposes an algorithm to perform the resource allocation in the uplink of an ieee802.16 standard-based system. the approach is valid for point to multi-point (PMP) and also for tree-deployed mesh networks, already defined for the Worldwide Interoperability for Microwave Access (WiMax). Our solution is based on a proportionally fair distribution of resources and it is formulated using the network utility maximization (NUM) framework. thanks to convex decomposition techniques, we derive a novel way of solving the NUM problem in a distributed manner. the goal is to attain the global optimal scheduling at the subscriber stations (SS) without the need of gathering information at a central node in the network. the results show significant gains in the time required to reach the optimal resource allocation for a given set of demands.
Localization of sensor nodes is a challenging and crucial issue in wireless sensor networks (WSNs), and high precision and low cost algorithms become the research direction. In this paper, a robust and accurate locali...
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Localization of sensor nodes is a challenging and crucial issue in wireless sensor networks (WSNs), and high precision and low cost algorithms become the research direction. In this paper, a robust and accurate localization algorithm based on adjustment of trilateration network (LATN) for WSNs is presented. Firstly, uncomplicated distributed algorithm is used for estimating position of the nodes, and the length of sides between neighbor nodes are gotten by RSSI measurement, subsequently, the information of every node is aggregated at sink node, and trilateration network will be constructed. According to the least square principle, localization error of whole network is depressed and precision of each node are estimated by mutual restraints of position error and side measurement error. Simulation results show that LATN is robust and not affected by network topology. In isotropic topology network, while average node degree of 10, reference node ratio is 20% and with side measurement error 0.1, the position error is improved 14% and 5% than DV-hop and DV-distance respectively.
A component framework plays an important role in CBSD as it determines how software components are developed, packaged, assembled and deployed. A desirable component framework for developing diverse cross-domain embed...
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ISBN:
(纸本)9780769533490
A component framework plays an important role in CBSD as it determines how software components are developed, packaged, assembled and deployed. A desirable component framework for developing diverse cross-domain embedded applications should meet such requirements as (1) lightweight on memory use, (2) integrated task execution model, (3) fast inter-component communication, (4) support for distributed processing, and (5) transparency from underlying communication middleware. Although current embedded system component frameworks address some of the above requirements, they fail to meet all of them taken together. We thus propose a new embedded system component framework called CREAM (component-based remote-communicating embedded application model). It achieves these goals by using build-time code generation, explicit control of task creation and execution in the component framework, static analysis of component composition to generate efficient component binding, and abstraction of the componentpsilas application logic from the communication middleware. We have implemented the CREAM component framework and conducted a series of experiments to compare its performance characteristics to a raw socket-based communication implementation and the lightweight-CCM implementation by MicoCCM.
Stationary wireless sensor networks (WSNs) fail to scale when the area to be monitored is open (i.e borderless) and the physical phenomena to be monitored may migrate through a large region. Deploying mobile sensor ne...
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Stationary wireless sensor networks (WSNs) fail to scale when the area to be monitored is open (i.e borderless) and the physical phenomena to be monitored may migrate through a large region. Deploying mobile sensor networks (MSNs) alleviates this problem, as the self-configuring MSN can relocate to follow the phenomena of interest. However, a major challenge here is to maximize the sensing coverage in an unknown, noisy, and dynamic sensing environment while minimizing energy consumption. Another major challenge is to maintain network connectivity for each MSN node during relocations. To address these challenges, we propose a new distributed algorithm, Causataxis 1 , that enables the MSN to relocate toward the interesting regions and adjust its shape and position as the sensing environment changes. Causataxis achieves scalable control of the MSN via a backbone-tree infrastructure maintained over clusterhead nodes, and achieves agility via localized cluster formation and dissolution. Unlike conventional cluster-based systems with backbone networks, a unique feature of our proposed approach is its bio-system inspired growing and rotting behaviors with coordinated locomotion. We compare Causataxis with a custom tuned swarm algorithm, which uses the concept of virtual spring forces to relocate mobile nodes based on local neighborhood information. Our simulation results show that Causataxis can outperform the swarm based algorithm in terms of the sensing coverage, the energy consumption, and the noise tolerance with a slightly high communication overhead.
In this paper, a new SVM (Support Vector Machines) synthesis method is presented. this method is based essentially on training criterion optimization of this machine by a set of hierarchical structures of learning aut...
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In this paper, a new SVM (Support Vector Machines) synthesis method is presented. this method is based essentially on training criterion optimization of this machine by a set of hierarchical structures of learning automata. this methodology is adopted for the development of off-line isolated handwritten digits recognition system. A comparison is taken between this new approach and that of a standard approach for SVM synthesis. these two methodologies are also compared with a neural network based classification method. the obtained results show the performances of the new suggested method for SVM synthesis.
Provisioning of rich routing building blocks to mobile ad-hoc networking applications has been of high interest. Several MANET applications need flexibility in describing paths their traffic will follow. To accommodat...
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Provisioning of rich routing building blocks to mobile ad-hoc networking applications has been of high interest. Several MANET applications need flexibility in describing paths their traffic will follow. To accommodate this need, previous work has proposed several viable routing schemes such as Dynamic Source Routing (DSR) and Trajectory-Based Routing (TBR). However, tradeoffs involved in the interaction of these routing schemes and the application-specific requirements have not been explored. Especially, techniques to help the application to do the right routing choices are much needed. We consider techniques that minimize routing protocol state costs under application-based constraints. We study the constraint of ldquoaccuracyrdquo of the applicationpsilas desired route, as this constraint provides a range of choices to the applications. As a crucial part of this optimization framework, we investigate the tradeoff between the packet header size and the network state. We, then, apply our framework to the case of TBR with application-based accuracy constraints in obeying a given trajectory. We begin with simple discrete models to clarify the tradeoff between packet header size and network state. We show that the problem of accurate representation of a trajectory withthe objective of minimizing the cost incurred due to header size and network state is difficult to solve optimally. Finally, we develop heuristics solving this problem and illustrate their performance.
the capacity of a wireless network has been widely studied in the literature, including the capacity for unicast and the capacity for broadcast. In this paper, we studied the capacity of a wireless network for broadca...
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the capacity of a wireless network has been widely studied in the literature, including the capacity for unicast and the capacity for broadcast. In this paper, we studied the capacity of a wireless network for broadcast. Previous studies on broadcast capacity either assume that all links in the wireless network has the same channel capacity, or assume that the transmission ranges of a wireless node can be arbitrarily large. In this paper we derive analytical upper bounds and lower bounds on broadcast capacity of a wireless network when all nodes in the network has the same bounded transmission power P and all nodes are placed in a square of side-length a. When the fixed data rate channel is used (each node can send W bits/second to nodes within its transmission range if no interference happened), we prove that the broadcast capacity is theta(W) under the physical interference model. When the Gaussian channel capacity is used, we show that the total broadcast capacity is only theta((alpharadic(log n/n)) -beta ) when alpharadic(log n/n) rarr infin. When a alpharadic(log n/n) rarr O(1), we show that the broadcast capacity is theta(1). We also generalize our results to multicast capacity for physical interference model.
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