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Gossip-Based Indexing Ring Topology for 2-Dimension Spatial Data in Overlay networks

Procedia Engineering 2012年 29卷 3727-3731页

作者： Z.Q. Zou Y. Wang B. Hu R.C. Wang College of Computer Nanjing University of Posts and TelecommunicationsNanjing Jiangsu 210003 China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing Jiangsu 210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Ministry of Education Jiangsu Province Nanjing Jiangsu 210003 China Key Laboratory of Virtual Geographic Environment Ministry of Education Nanjing Normal University Nanjing 210046 China

Overlay networks are used widely in the Internet, such as retrieval and share of files, multimedia games and so on. However, in distributed system, the retrieval and share of 2-dimension spatial data still have some difficult problems and can not solve the complex retrieval of 2-dimension spatial data efficiently. This article presents a new indexing overlay networks, named 2D-Ring, which is the ring topology based on gossip for 2-dimension spatial data. The peers in our overlay networks exchange the information periodically and update each local view by constructing algorithm. 2-dimension spatial data is divided by quad-tree and mapped into control points, which are hashed into 2D-Ring by SHA-1 hash function. In such way, the problem of 2-dimension spatial data indexing is converted to the problem of searching peers in the 2D-Ring. A large of extensive experiments show that the time complexity of constructing algorithm of 2D-Ring can reach convergence logarithmically as a function of the network size and hold higher hit rate and lower query delay.

关键词： Overlay networks 2-Dimension Spatial Data Indexing Gossip

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Efficient two-step entanglement concentration for arbitrary W states

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Physical Review A 2012年第4期85卷 042302-042302页

作者： Yu-Bo Sheng Lan Zhou Sheng-Mei Zhao Institute of Signal Processing Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China College of Telecommunications & Information Engineering 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 Nanjing 210003 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

We present two two-step practical entanglement concentration protocols for concentrating an arbitrary three-particle less-entangled W state into a maximally entangled W state assisted with single photons. The first protocol uses the linear optics and the second protocol adopts the cross–Kerr nonlinearity to perform the protocol. In the first protocol, based on the postselection principle, three parties say Alice, Bob, and Charlie in different distant locations can obtain the maximally entangled W state from the arbitrary less-entangled W state with a certain success probability. In the second protocol, the parties are not required to possess the sophisticated single-photon detectors and the concentrated photon pair can be retained after performing this protocol successfully. Moreover, the second protocol can be repeated to get a higher success probability. Both protocols may be useful in practical quantum-information applications.

关键词： Photons

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Efficient single-photon-assisted entanglement concentration for partially entangled photon pairs

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Physical Review A 2012年第1期85卷 012307-012307页

作者： Yu-Bo Sheng Lan Zhou Sheng-Mei Zhao Bao-Yu Zheng Institute of Signal Processing Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China College of Telecommunications & Information Engineering 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 Nanjing 210003 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

We present two realistic entanglement concentration protocols (ECPs) for pure partially entangled photons. A partially entangled photon pair can be concentrated to a maximally entangled pair with only an ancillary single photon with a certain probability, while the conventional ECPs require two copies of partially entangled pairs at least. Our first protocol is implemented with linear optics and the second protocol is implemented with cross-Kerr-nonlinearities. Compared with other ECPs, they do not need to know the accurate coefficients of the initial state. With linear optics, it is feasible with current experiments. With cross-Kerr-nonlinearities, it does not require sophisticated single-photon detectors and can be repeated to get a higher success probability. Moreover, the second protocol can get the higher entanglement transformation efficiency and it may be the most economical protocol by far. Meanwhile, both protocols are more suitable for multiphoton system concentration because they need less operations and classical communications. All these advantages make the two protocols useful in current long-distance quantum communications.

关键词： QUANTUM entanglement NONLINEAR theories PROBABILITY theory MULTIPHOTON processes QUANTUM communication OPTICAL communications

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Green Multimedia communications over Internet of Things

Green Multimedia Communications over Internet of Things

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IEEE International Conference on communications

作者： Liang Zhou Min Chen Baoyu Zheng Jingwu Cui Key Lab of Broadband Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Ministry of Education School of Computer Science and Engineering Seoul National University

ISBN: (纸本)9781457720529

In this paper, we consider a power-aware multimedia communications over internet of things (IoT). Specifically, we consider a generic IoT scenario where a multimedia server provides heterogeneous applications without knowing the application's quality of experience (QoE) model and playout period. Our objective aims at dynamically adjusting the power allocation for each application over a uncertain period to maximize the system overall mean opinion score (MOS). Note that the practical QoE model can be observed over time, but the underlying functional relationship between the power and MOS is unknown. The highlight of this paper is to develop a dynamic powering algorithm, in which one learns the satisfaction function and optimizes power-aware user satisfaction with on-line operation. More precisely, the proposed algorithm performance is measured in terms of loss which denotes the MOS loss compared to the optimal one. Numerical simulation results validate the efficiency of the proposed algorithm.

关键词： Internet of things Green multimedia communications Dynamic powering QoE model

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A novel adaptive resource allocation algorithm for multiuser ofdm-based cognitive radio systems

A novel adaptive resource allocation algorithm for multiuser...

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International Conference on network Computing and Information Security

作者： Jian, Zhang Qi, Zhu Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing China

ISBN: (纸本)9780769543550

Cognitive radio(CR) is a concept to improve the utilization of scarce spectrum resources in wireless communication, and orthogonal frequency division multiplexing (OFDM) is regarded as the best technology to match with the CR systems. In this paper, a new adaptive resource allocation algorithm for OFDM CR systems is presented. This algorithm solves the optimization problem based on maximize the total transmit bit rates of secondary users, on the one hand, the total transmit power of secondary users should below the transmit power constraint, on the other hand, the interference to primary users should under the maximum interference level, then allocate sub channels by an improved Hungarian Algorithm, and load bits and power by greedy algorithm. Simulation results show that the proposed algorithm can improve the system throughput comparing with some other sub optimal algorithms. © 2011 IEEE.

关键词： Cognitive radio

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BIPR: A new TCP variant over satellite networks

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Journal of China Universities of Posts and Telecommunications 2011年第SUPPL. 1期18卷 34-39页

作者： Xiao, Fu Sun, Li-Juan Wang, Ru-Chuan Fang, Yue-Chao College of Computer Science and Technology Nanjing University of Posts and Telecommunications Nanjing 210003 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 Nanjing 210003 China

Standard TCP perform poorly in satellite networks since the long delay, high bit error ratio and other characters. A new TCP variant, called BIPR for satellite networks is presented in this paper. Using the binary increase of window growth function, long bandwidth-delay product can be overcome, while probe method is also adopted in BIPR for conquer the high bit error rates in satellite links. Simulation results show that good performances in terms of throughput, link utilization and RTT fairness can be achieved in satellite networks using our method. © 2011 The Journal of China Universities of Posts and Telecommunications.

关键词： Satellites

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Detecting selective forwarding attacks in WSNs using watermark

Detecting selective forwarding attacks in WSNs using waterma...

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2011 International Conference on Wireless communications and Signal Processing, WCSP 2011

作者： Zhang, Deng-Yin Xu, Chao Siyuan, Lin Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China

ISBN: (纸本)9781457710100

This paper studies the selective forwarding attacks in wireless sensor networks (WSNs) and proposes a method to detect selective forwarding attacks based on digital watermarking technology. This method embeds watermark into the source data packets, which will be extracted at the base station (BS). The BS will judge whether there are malicious nodes in the transmission path by analyzing the packet loss rate from received data. Simulation results show that this method can effectively detect whether malicious nodes have discarded or tampered the contents of the packets. © 2011 IEEE.

关键词： Digital watermarking

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An improved game-theoretic spectrum sharing in cognitive radio systems

An improved game-theoretic spectrum sharing in cognitive rad...

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International Conference on communications and Mobile Computing

作者： Ma, Liang Zhu, Qi Key Lab. of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing China

ISBN: (纸本)9780769543574

In this paper, an improved game-theoretic spectrum sharing algorithm is proposed. Besides considering the available bandwidth, a reliance factor that represents how the primary users would like to lease the free spectrum to secondary users is introduced and the battery capacity of secondary users is taken into account. The simulation results show that the shared spectrum is in direct proportion to the reliance and battery capacity. The existence and uniqueness of Nash equilibrium are proved. © 2011 IEEE.

关键词： Cognitive radio

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Decentralized waveform design for MIMO cognitive radio under interference temperature constraint

Decentralized waveform design for MIMO cognitive radio under...

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2nd International Conference on networking and Distributed Computing, ICNDC 2011

作者： Wei, Fei Xia, Pengrui Yang, Zhen Tian, Feng Key Lab. of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing Jiangsu Province China

ISBN: (纸本)9780769544274

This paper addresses the information rate maximization problem under interference temperature constraint for a multiple-in multiple-out cognitive radio (MIMO-CR) network in which each CR user is equipped with multiple antennas. We formulate this as a Nash equilibrium problem where each CR tries to maximize its own utility by choosing appropriate wave-form. A decentralized iterative water-filling algorithm (IWFA) with pricing is proposed to solve it;the pricing mechanism is used to satisfy the interference temperature constraint while achieving the Nash equilibrium. Simulation results show that our algorithm can satisfy the interference temperature constraint perfectly and is fast convergent;we also show that the proposed IWFA with pricing can achieve a performance improvement in terms of sum-rate over the existed IWFA with power shaping. © 2011 IEEE.

关键词： Costs

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The controlled-worm system designwork

The controlled-worm system designwork

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2011 International Conference on Information technology, Computer Engineering and Management Sciences, ICM 2011

作者： Zhang, Dengyin Li, Dacheng Wang, Ye Key Lab. of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China

ISBN: (纸本)9780769545226

In order to solve the controllability problem of worm attack range and effect in network counterwork and achieve the precise attack on the target host, we propose a propagation control method based on lifetime and a damage control method based on atomic attack. Based on these, we design a kind of CWS (controlled-worm system) and implement the prototype system in the LAN. Implementation results show that CWS can not only control the survival time but also carry out targeted attacks on controlled hosts. Comparing with traditional controlled worms, the worm controlled by the CWS can attack targeted hosts with a certain degree of covertness and pertinence. © 2011 IEEE.

关键词： Atomic attack Attack control Controlled worm Propagation control survival time hosts

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