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An efficient coverage control algorithm for three-dimensional underwater sensor networks

Advances in Information Sciences and Service Sciences 2012年第10期4卷 393-399页

作者： Xiao, Fu Yang, Yang Sun, Li Wang, Ruchuan Nanjing University of Posts and Telecommunications Nanjing 210003 China Provincial Key Laboratory for Computer Information Processing Technology Soochow University Suzhou 215006 China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing 210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing 210003 China

Strategy of sensor nodes deployment is directly related to the cost and performance for underwater wireless sensor networks, which is largely determined the various service-quality improvement of wireless sensor networks. In order to improve the coverage of the target area, this paper presents a distributed algorithm of coverage control. Assume that nodes initially deployed on the surface of the water and can only move in vertical direction in 3-D space, the algorithm is first to control the nodes in-depth and relocate the nodes at different depths, then the nodes continue to adjust their depths until there is no augment for improving their coverage, and to achieve efficient coverage of the three-dimensional sensor networks ultimately. Experimental results show that compared with traditional random deployment method, the proposed coverage control algorithm can improve coverage of network effectively.

关键词： Quality control

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Data aggregation scheduling algorithm based on maximum weighted independent set for WSNs

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Journal of Information and Computational Science 2012年第15期9卷 4451-4459页

作者： Xu, Jian Yang, Geng Yang, Zhen Zhang, Zixiong College of Computer Science and Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Lab. of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China

Because sensor nodes are typically resource-constrained, the key challenge in wireless sensor networks (WSNs) design is the energy-efficiency and how to deal with the trade-off between it and the QoS parameters. Data Aggregation is an attractive technique able to cut down the data traffic, thereby reduce energy consumption, and extend the network lifetime. Meanwhile, the QoS performance of data aggregation rests with the aggregation scheduling algorithm. The previously proposed schemes consist of two phases: tree construction and scheduling. However most of them suffer from the following disadvantages: they must rely on some specific aggregation trees, and cannot guarantee the weighted fairness. Based on this defect, in this paper, we proposed an improved scheduling algorithm based on the Max Weighted Independent Set (MWIS). The aggregation scheduling methods presented here produce conflict-free schedules depending on the topology and data weight. The experiments results show that our approach have better performance in any arbitrary tree while the node of network have different priority to be scheduled. © 2012 by Binary Information Press.

关键词： Scheduling algorithms

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A tree-based data aggregation scheduling algorithm for wireless sensor networks

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Journal of Computational Information Systems 2012年第13期8卷 5409-5416页

作者： Xu, Jian Yang, Geng Liu, Zhipeng Chen, Yunfang College of Computer Science and Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Lab. of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China

Data aggregation is one of the key technologies for wireless sensor networks applications. Data aggregation can cut down the data traffic, thereby reduce energy consumption, and extend the network lifetime. But the QoS performance of data aggregation rests with the aggregation scheduling algorithm. The scheduling problems have been extensively studied recently, however most of them must rely on some specific aggregation trees and this restricts the applicability of those algorithms dramatically. In this paper, we proposed an improved scheduling algorithm, which is applicable for arbitrary aggregation tree topology. Based on the characteristics of the structure of the tree, we construct the transfer node set of each time slot, and implement the conflict-free data aggregation scheduling. The results of experiments show that our algorithm can reduce the delay of data aggregation process for various aggregation trees. © 2011 by Binary Information Press.

关键词： wireless sensor networks

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The research on network traffic modeling based on chaotic time series

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Journal of Computational Information Systems 2012年第8期8卷 3323-3330页

作者： Yin, Ansheng Zhang, Shunyi Qi, Jin Key Lab. of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China Institute of Information and Network Technology Nanjing University of Posts and Telecommunication No. 66 Xin Mofan Road Nanjing 210003 China

Spurred by the need of network monitoring and security, network traffic modeling is a much discussed research topic. However, the classical Markov flow model is no longer suitable for packet-switched network because of such network properties as self-similarity and long-range dependence. This paper presents a network traffic model based on chaotic time series which can predict the network traffic with smaller error than other models through experiments. © 2012 Binary Information Press.

关键词： Packet switching

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Ether net Ring Protection for ITU-T G.8032

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China communications 2012年第11期9卷 87-97页

作者： Wang Bin Wang Wennai College of Telecommunications and Information Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 P. R. China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Ministry of Education Nanjing 210003 P. R. China

Ethernet Ring Protection (ERP) introduced by ITU-T G.8032 Recommendation is a new type of packet-switched network protection technology, which can provide ring automatic protection switch. However, the Filtering Database (FDB) flush method adopted in the current ERP standard has the drawback of introducing a large amount of transient traffic overshoot caused by flooded Ethernet frames right after protection switching. In this article, we propose a G.8032 ERP scheme that uses FDB flush based on area to resolve this issue and investigate how the proposed scheme deals with the traffic flooding problem. The theoretical analysis and simulation show that the proposed scheme can effectively improve the performance of the Ethernet ring by decreasing the unnecessary FDB flush in comparison with the existing approaches.

关键词： carrier ethernet ERP FDB flush markov chain

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Error concealment techniques for video transmission over error-prone channels: a survey

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Journal of Computational Information Systems 2012年第21期8卷 8807-8818页

作者： Cui, Ziguan Gan, Zongliang Zhan, Xuefeng Zhu, Xiuchang Image Processing and Image Communication Lab Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Lab of 'Broadband Wireless Communication and Sensor Network Technology' Nanjing University of Posts and Telecommunications Ministry of Education China Institute of Physics and Communication Electronics Jiangxi Normal University Nanchang 330027 China

Efficient video transmission over unreliable channels may encounter huge challenge due to unavoidable bit error or packets loss. Error concealment (EC) techniques at the decoder side have been developed to recover the damaged regions utilizing spatial or temporal redundant information without changing the encoder structure or adding extra bandwidth. In this work the classic EC techniques and their developments are first reviewed, high-level semantics based EC schemes are also surveyed, and then the emphasis is focused on new EC features introduced by H.264/AVC. Finally, the challenges and future development directions in EC for advanced video coding schemes such as scalable video coding (SVC), multiple description coding (MDC), multi-view video coding (MVC) and stereo video coding are prospected, and future research directions are also indicated according to the current research status and existent problems. © 2012 Binary Information Press.

关键词： Scalable video coding

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Differential space-time block coding based cooperative spectrum sensing over fading environments in cognitive radio sensor networks

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Journal of Information and Computational Science 2012年第15期9卷 4599-4606页

作者： Chen, Zhi Yue, Wenjing College of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing 210003 China Key Lab. of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China

Incorporating cognitive radio capability in recource-constrainted multihop wireless sensor networks may help realize the deployment of multiple overlaid sensor networks, and eliminate collision and excessive contention delay incurred by dense node deployment. One of the main requirements of cognitive radio sensor networks is the ability to detect the presence of the primary user with fast speed and high accuracy in wireless environments. Cooperative spectrum sensing emerges as a promising candidate to meet these requirements. In practice, however, since the local sensing observations are forwarded to a sink through fading channels, the sensing performance of cooperative spectrum sensing is deteriorated due to the reporting errors introduced by the fading channels. To deal with this limitation, we propose a differential space-time block coding based cooperative spectrum sensing scheme to improve the sensing performance by decreasing the probability of reporting error. The sensing performance is also derived. Numerical results verify that better sensing performance can be achieved in proposed scheme compared to the conventional cooperative spectrum sensing. © 2012 by Binary Information Press.

关键词： Cognitive radio

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Mean shift object tracking with modified LTP

Mean shift object tracking with modified LTP

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International Conference on Signal Processing Proceedings (ICSP)

作者： Shaona Zhang Dong Hu Yanting Hu Education Ministry's Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications China School of Telecommunication and Information Engineering Nanjing University of Posts and Telecommunications China

A new scheme of object tracking with mean shift is put forward in this paper. At first, texture feature is fused in the processing by Local Ternary Pattern (LTP). Since LTP is sensitive to local noise, least median of squares (LMedS) algorithm is used to adaptively calculate the noise threshold for accurate estimation of the LTP texture information. Furthermore, target scale and orientation is estimated in case of partial occlusion or rotation, so as to realize robust object tracking. Experimental results show that the proposed algorithm can acquire robust tracking performance under complex background .

关键词： Histograms Target tracking Image color analysis Object tracking Heuristic algorithms Computational modeling Kernel

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Relay power allocation in auction-based game approach

Relay power allocation in auction-based game approach

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IEEE Global communications Conference

作者： Dan Wu Yueming Cai Zhou, Liang Rodrigues, Joel Institute of Communications Engineering PLA University of Science and Technology The Key Lab of Broadband Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Ministry of Education Institute de Telecomunicacoes University of Beira Interior

ISBN: (纸本)9781467309202

In this work, with respect to the uncertainty about the individual information, we investigate the relay power allocation problem from the energy-efficient, Pareto optimal, and competitive fairness perspective. At first, we design an easy-implementation energy efficiency metric, which aims at striking a balance between the QoS provisioning and the energy consumption. Then, an auction mechanism is proposed for relay power allocation. By transferring the auction mechanism into a game, we prove the existence, uniqueness, and Pareto optimality of the Nash equilibrium (NE) for our auction game, and show that the allocation strategies from the NE can achieve the energy efficiency in terms of the proposed metric. Next, we develop a distributed relay power allocation algorithm based on our best-response functions to reach the Pareto optimal NE. Importantly, we not only certify the convergence of the proposed algorithm, but also provide quantitative analysis on it. Extensive simulations results are conducted to confirm the validity of the analytical results.

关键词： wireless cooperative networks Auction theory Energy efficiency Power allocation Outage probability

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A non-deterministic evaluation on SLA in cloud markets

International Journal of Digital Content Technology and its ...

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International Journal of Digital Content technology and its Applications 2012年第23期6卷 838-848页

作者： Xu, Jin-Song Yang, Geng Huang, Wan-Ming Xu, Xiao-Long Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education China College of Computer Nanjing University of Post and Telecommunications China TongDa College Nanjing University of Post and Telecommunications China State Key Laboratory for Novel Software Technology Nanjing University China

The primary issue in dynamic cloud computing environments is how to select and schedule the ideal and different cloud resources to cooperation in order to guarantee the requirements of applications. This paper proposed a novel cloud services selection algorithm for hierarchy evaluation of SLA, which is selecting the proper resources to compromise services. The service level agreement can only ensure completion of the application. Through fuzzing the SLA attribute, this paper conducted a non-deterministic evaluation on the SLA attribute data provided by cloud service providers using variable weights. Based on the relationships among different SLA attributes, a better cloud service will be selected in a Service Oriented Architecture. The experimental results show the effectiveness of the algorithm: there is no force in the relationship between sub-tasks in the case, each cloud resource and service providers can effectively reduce the cost of application based on recommendations;with the introduction of mandatory use of strong relationships and recommendation of service resources, the effectiveness of the application is ensured while reducing the total consumption of services;the right way to use fuzzy variable cloud resources involved in service evaluation will help to cut the cost of commercial cloud services and providing users with better services.

关键词： Cloud computing

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