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The 2014 5th International Conference on Environmental Science and Information Application technology(ESIAT 2014)

作者： Mingxiang Wan Chunshao Ren Dengyin Zhang Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and TelecommunicationMinistry of Education Sci-tech Park of Internet of Things Nanjing University of Posts and Telecommunication

B+ Tree is a special balanced multiway tree with flexible structure and node pages linking to each *** supports not only rapid random query,but also range *** B+ Tree index cannot be directly migrated since data storage architecture is different in cloud *** on the characteristics of cloud computing master-slave architecture and combined with the characteristics of the columnar storage in the cloud environment,this paper proposes an improved secondary index of B+ *** this index,primary key still uses key-Value style hash index,which can not only get high search efficiency,but also maintain load balance;other property columns will apply improved B+ Tree index,which can solve the problem of high time complexity when querying non-primary key and also support range query of non-primary key property.

关键词： An improved static B tree index adaptive to cloud environment for analytic application

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A low communication cost and delay guaranteed multicast approach for next generation vehicular ad hoc networks

A low communication cost and delay guaranteed multicast appr...

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IEEE International Conference on Consumer Electronics-Taiwan (ICCE-TW)

作者： Chengchao Ji Zhengkun Mi Wennai Wang Shenghui Zhao School of Computer and Information Chuzhou University Chuzhou China Key Lab of Broadband Wireless Communication and Sensor Network Technology (Ministry of Education) Nanjing University of Posts and Telecommunications Nanjing China

Vehicle Ad hoc networks (VANETs) is an emerging wireless network technology whereby information is generally shared among vehicles through multi-hopping In literature, a number of routing approaches has been proposed for reducing the end-to-end delay. However, the routing approaches applied to support multicast service will be inefficient since none of them considered the share path in VANETs. This paper considers the delay-bound guaranteed multicast service where a vehicle aims to send a message to a group of vehicles using minimal bandwidth within a guaranteed delay bound. The source and multicast destinations are location-aware and trip-aware. Therefore the multicast approach developed for VANETs is totally different to the one in ad hoc networks. The proposed approach forwards the multicast message to the vehicles in the multicast group along the road segment with the least time cost, reserving as much as possible the remaining time for carry-and-forward transmissions which helps reduce the bandwidth consumption for packet transmissions.

关键词： Vehicles Routing Delays Roads Integrated circuits Vehicular ad hoc networks Educational institutions

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A Model-Matching Algorithm Based on Improved BP over Out-of-order Streams

A Model-Matching Algorithm Based on Improved BP over Out-of-...

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IEEE International Conference on communications

作者： Kun Wang Linchao Zhuo Lei Shu Yanfei Sun Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing China Guangdong Provincial Key Lab. of Petrochemical Equipment Fault Diagnosis Guangdong University of Petrochemical Technology Guangdong China

Due to the explosive increment of data in big data era, it is a challenging task to analyze and extract meaningful data for users. Data needs to be timely operated because of the time sensitivity, so it faces enormous pressure in storage and computing. To deal with the problem that it is hard to achieve valuable information from out-of-order streams over big data in short time, a model-matching algorithm based on improved BP (Back Propagation) is proposed. In the algorithm, the matching model is set dynamically. Information is extracted for users according to the order of data's arriving time. Furthermore, the algorithm parameters are automatically adjusted in the process of learning and matching. Accordingly, the responding speed of learning is accelerated and the time of matching reduces. In the simulation, a group of optimum parameters of improved BP are achieved by using self-adapting adjusting mechanism. The threshold (TH), connecting weight (CW) and learning rate (LR) are equal to 1.5, 3 and 1, respectively. We implement our model-matching algorithm on 10000 sets of out-of-order streams with these parameters. Results indicate that the proposed algorithm can obviously improve the accuracy and speed of matching and achieve better stability.

关键词： Heuristic algorithms Mathematical model Out of order Convergence Accuracy Data models Software algorithms

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Quantum bacterial foraging optimization algorithm

Quantum bacterial foraging optimization algorithm

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Congress on Evolutionary Computation

作者： Fei Li Yuting Zhang Jiulong Wu Haibo Li Key Lab of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing China Department of Applied Physics and Electronics Umea University Umea Sweden

ISBN: (纸本)9781479914869

This paper proposes a novel swarm intelligence optimization method which integrates bacterial foraging optimization (BFO) with quantum computing, called quantum bacterial foraging optimization (QBFO) algorithm. In QBFO, a multi-qubit which can represent a linear superposition of states in search space probabilistically is used to represent a bacterium, so that the quantum bacteria representation has a better characteristic of population diversity. A quantum rotation gate is designed to simulate the chemotactic step to drive the bacteria toward better solutions. Several tests are conducted based on benchmark functions including multi-peak function to evaluate optimization performance of the proposed algorithm. The numeric results show that the proposed QBFO has more powerful properties in convergence rate, stability and the ability of searching for the global optimal solution than the original BFO and quantum genetic algorithm. In addition, we applied our proposed QBFO to solve the traveling salesman problem, which is a well-known NP-hard problem in combinatorial optimization. The results indicate that the proposed QBFO shows better convergence behavior without premature convergence, and has more powerful properties in convergence rate, stability and the ability of searching for the global optimal solution, as compared to ant colony optimization algorithm and quantum genetic algorithm.

关键词： Microorganisms Quantum computing Optimization Convergence Benchmark testing Sociology Statistics

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A strategy for fault management in LDC wireless sensor network

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Computer Modelling and New Technologies 2014年第8期18卷 158-163页

作者： Yang, Jian College of Computer Nanjing University of Posts and Telecommunications Nanjing Jiangsu China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing Jiangsu China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing Jiangsu China

With rapid development of hardware, wireless sensor networks (WSN) have been applied in a wide range of fields. However, energy cost constrains putting WSN into use. To reduce energy cost, extending life time, WSN in low-duty-cycle (LDC) draws researchers' attention. In general, work time of a node only occupies 0.1%-10% in a cycle. This model certainly reduces the energy for idle listening. On the other hand, it makes the probability of congestion very high due to a node that can only receive packets when waking up. This paper proposes a new LDCWSN model to solve the congestion from duty schedule. With the model, we show a strategy for WSN fault averting, diagnosing and recovery based on congestion in nodes. We include some attributes of LDC WSN in our strategy, i.e. probability of congestion, scheduler, and link quality. By improving the selection of nodes on every level, we get a low rate for network's fault appearance, low E2E delay and long lifetime. The simulation's result shows that our strategy has a better performance in packet loss, energy cost and time delay than proposed WSN fault management.

关键词： sensor nodes

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Perfect Power Visualization-Performance Optimization with Java

Perfect Power Visualization-Performance Optimization with Ja...

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2014 IEEE 5th International Conference on Software Engineering and Service Science

作者： Chenqi Bao Alexander Flueck Jianmin Bao Xuan Shen Computer of Engineering Illinois Institute of Technology (College of IOTNanjing University of Posts and Telecommunications)Ministry of Education Key Lab of Broadband Wireless Communication and Sensor Network Technology (College of IOT Nanjing University of Posts and Telecommunications)Ministry of Education

Visualization is critical in power systems engineering since the gigantic amount of data generated by power systems is difficult,and at times impossible,to be analyzed numerically. Therefore,the need for powerful visualization software has been increasingly acute due to the growth in size of power system models. To improve PPV’s performance in order to accompany larger systems,this paper focuses on the development of PPV (Perfect Power Visualization),a 2-D power system visualization software program that processes and conver ts numerical data to graphic symbols based on their types,positions and states. The goal of PPV is to let operators visualize and interact with large-scale power systems in a consumer lever personal computer in real time. Also,it was optimized again with smarter data management systems,refinement of overall structure,and a newer platform that enables GPU acceleration,all of which further increased the performance of PPV by a factor of ten times that of its initial capabilities.

关键词： PPV,Power System Visualization,Java FX,GPU acceleration,Performance Optimization

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Low-power task scheduling algorithm for large-scale cloud data centers

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Journal of Systems Engineering and Electronics 2013年第5期24卷 870-878页

作者： Xiaolong Xu Jiaxing Wu Geng Yang Ruchuan Wang College of Computer Nanjing University of Posts and Telecommunications State Key Laboratory for Novel Software Technology Nanjing University Key Lab of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications

How to effectively reduce the energy consumption of large-scale data centers is a key issue in cloud computing. This paper presents a novel low-power task scheduling algorithm （L3SA） for large-scale cloud data centers. The winner tree is introduced to make the data nodes as the leaf nodes of the tree and the final winner on the purpose of reducing energy consumption is selected. The complexity of large-scale cloud data centers is fully consider, and the task comparson coefficient is defined to make task scheduling strategy more reasonable. Experiments and performance analysis show that the proposed algorithm can effectively improve the node utilization, and reduce the overall power consumption of the cloud data center.

关键词： cloud computing data center task scheduling energy consumption.

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A grouping dynamic framed slotted ALOHA collision tracking algorithm

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Journal of Computational Information Systems 2014年第9期10卷 3989-3996页

作者： Zhang, Xuejun Ye, Chuanling Tian, Feng Sun, Zhixin Key Laboratory of Broadband Wireless Communication and Sensor Network Technology of Ministry of Edu. Nanjing University of Posts and Telecommunications Nanjing 210003 China School of Electronic Science and Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China

This paper proposed an improved grouping tag anti-collision algorithm based on the dynamic framed slotted ALOHA algorithm and collision tracking tree algorithm. The analysis of performance and the result of simulation show that this algorithm though combining the ALOHA-based algorithm, tree-based algorithm and grouping theory, improve the throughput of the system efficiency and reduce the total query the number of slots. © 2014 Binary Information Press.

关键词： Radio frequency identification (RFID)

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Impact of MAC frame length on energy efficiency in 6LowPAN

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The Journal of China Universities of Posts and Telecommunications 2013年第4期20卷 67-72页

作者： CHEN Shou-ning YANG Long-xiang ZHAO Yu-juan LI Jing Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Jiangsu Mobile Communication Company Limited Nanjing Branch

To reach necessary end-to-end connectivity between the Internet and wireless sensor networks （WSNs）, the Internet Engineering Task Force （IETF） IPv6 over low power wireless personal area network （6LowPAN） working group has been established and introduced an adaptation layer for integration of IEEE 802.15.4 physical layer/media access control （PHY/MAC） layers and the upper layers of any Intemet protocol （IP）-based networks, such as the Internet. The energy efficiency is one of the most important performance measures in WSNs because most sensor nodes are only battery powered so we should reduce the energy consumption to the lowest to extend the life of nodes. Therefore the determination of MAC frame length should be carefully considered since that the radio frequency （RF） module consumes most the energy of a sensor node meanwhile the MAC protocol is the direct controller of RF module. In this paper, we provide a star-shaped 6LowPAN non-beacon mode with unslotted carrier sense multiple access with collision avoidance （CSMA/CA） mechanism to access to the channel and model the stochastic behavior of a target end node as the M/G/1 queuing system. Analytical expressions for some parameters such as channel busy probability, packet loss probability and energy efficiency are obtained in this paper and our analytical results can clearly show the impact of MAC frame length on the energy efficiency of a target node in both ideal and lossy channel.

关键词： 6LowPAN IEEE 802.15.4 unslotted CSMA/CA M/G/1 queuing system MAC frame length energy efficiency

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Secure P2P topology based on a multidimensional DHT space mapping

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Science China(Information Sciences) 2013年第5期56卷 224-237页

作者： SUN ZhiXin LUO BingQing CHEN YaDang BU Kai Key Laboratory of Broadband Wireless Communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of Education State Key Laboratory for Novel Software Technology Nanjing University

Distributed search and routing algorithms based on the DHT(distributed hash table) protocol have attracted considerable attention in structured P2P(peer-to-peer) research as a result of favorable properties such as distribution,self-organization,and high *** with a traditional C/S(client/server) network,the probability of peers initiating malicious behavior increases dramatically because of their self-governing and dynamic characteristics,which also make it harder to satisfy the peers’ security required by *** this paper,we propose a new secure DHT protocol based on a multidimensional mapping *** mechanism maps peers to a multidimensional space by dividing the identifiers into ***,a series of secure methods and routing algorithms are provided to achieve secure DHT in smaller *** with state-ofthe-art approaches,the theoretical analysis and experimental results show that the multidimensional mapping mechanism can effectively improve the average success rate of a resource search by inhibiting malicious behavior.

关键词： multidimensional mapping DHT(distributed hash table) structured P2P(peer-to-peer) network routing attack security

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