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An improved cognitive radio spectrum sensing algorithm

Telkomnika - Indonesian Journal of Electrical Engineering 2013年第2期11卷 583-590页

作者： Zhang, Dengyin Li, Kuankuan Xiao, Li Key Lab of Broadband Wireless Communication and Sensor Network Technology China Nanjing University of Posts and Telecommunications Ministry of Education China School of Telecommunication Information Engineering China

To improve the cognitive radio user's detection performance and reduce the complexity, this paper composites the Fractal box dimension algorithm and the 3th-order cyclic-cumulate (TCC) algorithm and improves the TCC algorithm, so a novel detection algorithm is proposed that the Fractal box dimension is used when the signal to noise (SNR) is high, while the improved TCC algorithm is used when the SNR is low. This new algorithm not only avoids using TCC algorithm with high complexity when the channel environment is good, but also reduces the decision complexity of TCC algorithm. Simulation result shows that this algorithm obtains good detection performance with lower complexity than the traditional TCC algorithm. © 2013 Universitas Ahmad Dahlan.

关键词： Cognitive radio

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Sparse and low-rank matrices recovery from incomplete and noisy measurement

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Journal of Computational Information Systems 2013年第19期9卷 7703-7710页

作者： Yang, Zhenzhen Yang, Zhen College of Communication and Information Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Lab. of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China

The problem of recovering sparse and low-rank matrices from a given matrix captures many applications. However, this recovery problem is NP-hard and thus not tractable in general. Recently, it has been shown that this NP-hard problem can be well approached via heuristically solving a convex relaxation problem where the ?1-norm and the nuclear norm are used to induce sparse and low-rank structures, respectively. To capture more applications, this paper studies the recovery problem in a more general setting: the matrix is acquired by compressed measurement and the measurement is corrupted by Gaussian noise. The separable structure of the new model enables us to solve the involved subproblems more efficiently by splitting the multipliers function. Hence, an implementable numerical algorithm which called accelerated alternating direction method of multipliers (AADMM) is proposed to solve the novel model. Our experimental results show that AADMM is surprisingly efficient for solving the new recovery model. © 2013 Binary Information Press.

关键词： Recovery

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An AUVs-aided localization scheme for underwater wireless sensor networks

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Journal of Computational Information Systems 2013年第19期9卷 7711-7718页

作者： Liu, Linfeng Liu, Qianqian Wu, Jiagao Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of Edu. Nanjing 210003 China School of Computer Nanjing University of Posts and Telecommunications Nanjing 210023 China

Since radio communication can not work well underwater, there are still many difficulties and challenges for localization technology of underwater wireless sensor networks (UWSN). In order to improve the localization accuracy, we propose an Autonomous Underwater Vehicle (AUV) aided localization scheme for UWSN. The first positioning for unknown nodes should be completed, simultaneously, the localization accuracy of every unknown node is estimated based on the number, the distribution and the distance of neighboring beacon nodes. Accordingly, some nodes with lower accuracy are filtered out, then AUVs will move to suitable place and give assistance to the secondary positioning of these nodes. Both theoretical analysis and simulation results suggest that this scheme can improve the positioning accuracy effectively by the assistance of AUVs. Moreover, the computation and complexity of this scheme are proven preferable as well. © 2013 Binary Information Press.

关键词： Radio communication

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An authentication and encryption scheme of network management message based on device fingerprint

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Information technology Journal 2013年第6期12卷 1206-1212页

作者： Zhang, Dengyin Xu, Jinlian Cheng, Chunling Xue, Qinghan Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China College of Computer Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China

With the continuous development of the converged network, the types of equipment increase and each has different device identification. The existing SNMPv3 program by using enginelD to identify equipment's legal status and confirm the security of message transmission can't meet the safety management for complex equipments in converged network. The concept of device fingerprint is proposed in accordance to specify and mark kinds of equipments in converged network with its structure defined and generation method designed specifically. The local-key generation program based on device fingerprint and the improved authentication and encryption process of network message are described. Experiment by expanding the definition of MTB and dynamically generating device fingerprint show this scheme protecting the security of network communications in the message authentication and encryption process and achieving security management for complex equipments in converged network. Finally, this study analyzes the safety and practicality of using this scheme in converged network. © 2013 Asian network for Scientific Information.

关键词： Authentication

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DAS: A Dynamic Assignment Scheduling Algorithm for Stream Computing in Distributed Applications

DAS: A Dynamic Assignment Scheduling Algorithm for Stream Co...

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IEEE Global communications Conference

作者： Kun Wang Yu Yue Bo Liu Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China Department of Electronic Engineering Shanghai Jiaotong University Shanghai 200240 China.

ISBN: (纸本)9781479913510

Due to the unpredictability of continuous data in distributed applications, it is hard for system to deal with data explosion in limited time. As a result, traditional static data storage technology fails to meet the demands for real-time data processing. To improve processing ability, many parallel processing structures are proposed, which brings up the problem that how the parallel machines can be scheduled to maximize their efficiency. Accordingly, a dynamic assignment scheduling algorithm for stream computing is proposed and a stream query graph is built to calculate the weight of every edge. The edge with the minimum weight is selected to send tuples. Simulation results show that the proper number of the logic machines could dramatically reduce system response time. Furthermore, system context switching is reduced by increasing the number of tuples sent every time.

关键词： stream computing dynamic scheduling stream query graph distributed applications

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Research of new real-time trust monitoring model base on multiple behavior attributes

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Information technology Journal 2013年第18期12卷 4776-4782页

作者： Zhang, Lin Liu, Zhengbang Rao, Kaili Wang, Ruchuan College of Computer Nanjing University of Posts and Telecommunications 210003 Nanjing China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Jiangsu Province 210003 Nanjing China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nangjing University of Posts and Telecommunications Ministry of Education Jiangsu Province 210003 Nangjing China

In order to ensure the reliability and security of working environments under the open network environment dynamically,a fine-grain real-time and dynamic trust monitoring model is proposed which is based on behavior attribute factor, penalty factor of bad frequency, penalty factor of reputation, penalty factor of hazard-warning frequency, union-recommendation trust, etc. Through monitoring the behavior change in the context of service nodes, the calculating method about the behavior risk value is discussed which is based on the degree of damage about bad behaviors. This can provide convenience for making new *** work is completed, the updating method about trust encouragement or punishment is given. Experiment results show that the new real-time trust monitoring model is accurate and effective. © 2013 Asian network for Scientific Information.

关键词： Dynamic trust Open network environment Trust monitoring Trust updating

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Trade-off between Delay and Bandwidth Utilization for Heterogeneous sensor networks

Trade-off between Delay and Bandwidth Utilization for Hetero...

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IEEE Globecom Workshops

作者： Jianxin Chen Liang Zhou Baoyu Zheng Jingwu Cui Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications

ISBN: (纸本)9781479928521

Heterogeneous wireless sensor network (HWSN) consists of sensor nodes with different ability, such as computing power and sensing range. Compared with homogeneous wireless sensor network, the design of protocols for such networks has to be more complex due to the energy constraint in order to prolong the lifetime of the network. As energy consumption mostly comes from the radio transmissions, bandwidth utilization affects the network lifetime greatly. In this paper, a novel lossless data aggregation scheme (Better-to-Fit) is presented for the clustering-based HWSN to improve the bandwidth utilization without introducing extra computation. The average performance is evaluated theoretically and validated by simulations. It has been found that the proposed aggregation technique can minimize the aggregation time under energy constraint and achieve promising efficiency in terms of bandwidth utilization.

关键词： wireless sensor network Heterogeneous traffic Data aggregation Bandwidth Utilization

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Clustering facilitated web services discovery model based on supervised term weighting and adaptive metric learning

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International Journal of Web Engineering and technology 2013年第1期8卷 58-80页

作者： Chen, Lei Yang, Geng Zhu, Wei Zhang, Yingzhou Yang, Zhen College of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China

With the explosive growth of web services, the research on how to rapidly find the desired services becomes increasingly important and challenging. In this paper, we focus on non-semantic web services discovery and present an efficient clustering facilitated web services discovery model (CFWSFinder). Compared with the existing models, CFWSFinder has several characteristics. First, in services representing process, CFWSFinder imports WordNet and latent semantics index to represent non-semantic web services as the low-dimensional compact semantic feature vectors;Second, in services clustering process, CFWSFinder employs a modified Kernel batch self-organising map (KBSOM) neural network to minimise the services discovery duration;Third and most importantly, in services matching process, by using the category label information achieved from services clustering process, CFWSFinder can adopt supervised term weighting scheme and adaptive metric learning method to ameliorate the services discovery precision. Finally, experimental results performed on the real-world web services collection demonstrate the feasibility of the CFWSFinder. Copyright © 2013 Inderscience Enterprises Ltd.

关键词： Web services

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Fairness-oriented physical layer network coding in cooperative multiple access channels due to MRC and SIC

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The Journal of China Universities of Posts and Telecommunications 2012年第6期19卷 45-51页

作者： CHENG Yu-lun YANG Long-xiang Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications

This paper investigates the impacts of network coding （NC） on user fairness from the network perspective in multiple access channels. Firstly, simultaneous outage is exploited as the metric to evaluate user fairness. To optimize it, a fairness-oriented physical layer NC scheme is proposed, in which users＇ signals are superimposed in specific calculated proportion at relay and then decoded by maximal ratio combination （MRC） and serial interference cancellation （SIC） at destination. Furthermore, the influence of power allocation coefficient error on simultaneous outage is also analyzed to reveal its correlation with user fairness. Simulation results indicate that the proposed scheme can supply approximately equal performance promotion for each cooperation-participated user and outperform those without fairness consideration in terms of the employed metric.

关键词： cooperative system user fairness simultaneous outage MRC SIC

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A trust information search model based on simulated annealing in P2P network

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Information technology Journal 2013年第15期12卷 3289-3293页

作者： Xu, He Huang, Han-Chen Wang, Ruchuan College of Computer Nanjing University of Posts and Telecommunications Jiangsu Nanjing 210003 China Jiangsu High Technology Research Key Laboratory Wireless Sensor Networks Jiangsu Nanjing 210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Jiangsu Province Nanjing 210003 China Department of Leisure Management Yu Da University Miaoli 36143 Taiwan

Trust information search algorithm is one of the most important components of P2P trust model. Considering the large number of nodes and the wide range of information each node contains in P2P network, efficient search algorithm can improve the network efficiency and attract more users to join P2P network. Moreover, efficient search algorithm can also let each node in the network know the current state of the network in time. This study designs an SABS (Simulated Annealing Based Search) model based on Simulated Annealing (SA) to search the trust information in P2P network. Simulation results show that this model can obtain the optimal path and the shortest distance of the network with appropriate parameter values. © 2013 Asian network for Scientific Information.

关键词： Simulated annealing

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