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arXiv 2018年

作者： Li, Wei Zhao, Shengmei Nanjing University of Posts and Telecommunications Institute of Signal Processing and Transmission Nanjing210003 China Nanjing University of Posts and Telecommunications Key Lab Broadband Wireless Communication and Sensor Network Ministy of Education Nanjing210003 China Sunwave Communications Hangzhou310053

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An Integrated Optimization Model for Urban Agglomeration Traffic and Land Use Based on Multi-objective Particle Swarm Optimization Algorithm

An Integrated Optimization Model for Urban Agglomeration Tra...

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IEEE International Conference on Intelligent Transportation Engineering (ICITE)

作者： Jiaqi Wu Yang Yu Wenqiang Xue Qinyuan Zhang College of Transportation science & Technology Nanjing Tech University Nanjing Key Lab of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing YangZhou Urban Planning and Research Geography Information Information Center Hexi Campus International Department Jinling High School

Based on the mutual relationship between traffic and land use, the Integrated Transportation and Land Use Model (ITLM) is established from the perspective of urban agglomeration development. The model parameters are calibrated by using MATlab and ArcGIS in combination with information entropy model and Multi-objective Particle Swarm Optimization. From the macro and meso perspectives, the space syntax is used to quantify the transport links of cities in urban agglomerations. Taking the Yangtze River City Group as an example, combined with big data analysis by POI, after optimization of the land use area, population size, and traffic structure of various types of nature through the ITLM model, traffic occurrence and attraction of cities in urban agglomerations tend to be more balanced than the current situation. It plays a vital role in analyzing the current status of cities in urban agglomerations and promoting the further development of urban agglomerations.

关键词： Urban areas Transportation Sociology Statistics Mathematical model Optimization Particle swarm optimization

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Quality-delay tradeoff for video streaming over mobile ad hoc networks

Quality-delay tradeoff for video streaming over mobile ad ho...

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IEEE International Conference on communications (ICC)

作者： Liang Zhou Yan Zhang Joel Rodrigues Benoit Geller Jingwu Cui Baoyu Zheng Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications China Simula Research Laboratory Norway Instituto de Telecomunicaçőes University of Beira Interior Portugal Laboratory of UEI ENSTA Paristech France

In this work, we study the quality-delay tradeoff for video streaming over mobile ad hoc network by utilizing a class of scheduling schemes. We show that node spatial mobility indeed impacts on the performance of wireless video transmission under the assumption that all the nodes can identically and uniformly visit the entire network. To describe a practical mobile scenario, we consider a random walk mobility model in which each node can randomly and independently choose its mobility direction at each time-slot. The contributions of this work are twofold: 1) It investigates the optimal node velocity for the mobile video network which helps to identify the impact of mobility on the video performance; 2) It derives the achievable quality-delay tradeoff range for any node mobility velocity, and thus it is helpful to design appropriate quality and delay requirements. These results provide insights on network design and fundamental guidelines on establishing an efficient mobile wireless video transmission system.

关键词： Streaming media Delay Mobile ad hoc networks wireless communication Video recording Quality assessment

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Reconfigurable vortex beam generator based on the Fourier transformation principle

arXiv

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arXiv 2018年

作者： Liu, Aiping Zou, Chang-Lin Ren, Xifeng He, Wen Wu, Mengze Guo, Guangcan Wang, Qin Affiliation: Institute of Quantum Information and Technology Nanjing University of Posts and Telecommunications Nanjing210003 Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing210003 Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China Hefei230026 China

A method to generate the optical vortex beam with arbitrary superposition of different orders of orbital angular momentum (OAM) on a photonic chip is proposed. The distributed Fourier holographic gratings are proposed to convert the propagating wave in waveguides to a vortex beam in the free space, and the components of different OAMs can be controlled by the amplitude and phases of on-chip incident light based on the principle of Fourier transformation. As an example, we studied a typical device composed of nine Fourier holographic gratings on fan-shaped waveguides. By scalar diffraction calculation, the OAM of the optical beam from the reconfigurable vortex beam generator can be controlled on-demand from ?2nd to 2nd by adjusting the phase of input light fields, which is demonstrated numerically with the fidelity of generated optical vortex beam above 0.69. The working bandwidth of the Fourier holographic grating is about 80 nm with a fidelity above 0.6. Our work provides an feasible method to manipulate the vortex beam or detect arbitrary superposition of OAMs, which can be used in integrated photonics structures for optical trapping, signal processing, and imaging. Copyright © 2018, The Authors. All rights reserved.

关键词： Incident light

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Layered Compression Scheme for Efficient Data Collection of sensory Data

Layered Compression Scheme for Efficient Data Collection of ...

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International Conference on Computer communication and networks

作者： Siguang Chen Shujun Zhang Bin Xu Jing Hu Vijayakumar Varadarajan Jiangsu Engineering Research Center of Communication and Network Technology Nanjing University of Posts and Telecommunications Nanjing China Key Lab of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing China Information Center Jiangsu China Tobacco Industry Co. Ltd. Nanjing China School of Computing Science and Engineering VIT University Chennai India

Although the existing compressed sensing (CS) based spatio-temporal data compression schemes can significantly decrease communication consumption for data collection, they ignore the data correlation among different clusters over spatial dimension. Actually, the discovery and utilization of spatial correlation among different clusters can further increase the compression rate (or improve the recovery effect). In this paper, we propose a layered compression scheme for efficient data collection of sensory data (LCS-EDC). In the proposed scheme, first, we design a multi-layer network architecture to support the exploration of spatio-temporal correlations, especially for exploring the spatial correlation among different clusters. And then, we construct the specific projection methods respectively for exploring the temporal correlation in sensory nodes, spatial correlation (intra-cluster) in cluster heads and spatial correlation (inter-cluster) in processing nodes. Meanwhile, the detailed solving method is developed to recover original data and achieve the approximate data collection in sink node. Finally, simulation results indicate that the proposed layered compression scheme has better recovery performance as compared with traditional clustered compression schemes (i.e., achieving efficient data collection with high quality).

关键词： Compressed sensing data correlation multi-layer architecture data collection recovery error

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Fair Downlink Traffic Management for Hybrid LAA-LTE/Wi-Fi networks

Fair Downlink Traffic Management for Hybrid LAA-LTE/Wi-Fi Ne...

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IEEE Global communications Conference

作者： Yang Li Mengying Zhang Yang Yang Xudong Wang School of Information Science and Technology ShanghaiTech University Key Lab of Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences UM-SJTU Joint Institute Shanghai Jiao Tong University

ISBN: (纸本)9781509013296

Due to the scarcity of the licensed spectrum, Licensed-Assisted Access Long-Term Evolution (LAA-LTE) network can be deployed in unlicensed spectrum, which is currently occupied by different Wi-Fi systems. It is a very challenging problem to ensure fair coexistence between LAA-LTE and Wi-Fi networks, in terms of spectrum sharing and traffic management. To solve this problem, a Fair Downlink Traffic Management (FDTM) scheme is proposed in this paper for hybrid LAA-LTE/Wi-Fi networks. By using the genetic algorithm, FDTM tunes the minimum Contention Window (CW_(min)) values and assigns feasible weights for the LAA eNBs with different traffic loads, thus to achieve (1) fair spectrum sharing with the existing Wi-Fi networks in unlicensed bands, and (2) fair service differentiation for downlink LAA-LTE traffic. Numerical results show our FDTM scheme can guarantee the throughput of Wi-Fi networks in shared unlicensed spectrum, while supporting proportional fairness for the LAA eNBs with different weights and CW_(min) values.

关键词： IEEE 802.11 Standard Throughput Downlink Genetic algorithms Long Term Evolution Biological cells Electronic mail

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Outage Performance Analysis and Parameter optimization of Hovering UAV-Based FSO System

Outage Performance Analysis and Parameter optimization of Ho...

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IEEE International Conference on communications (ICC)

作者： Yang Ma Jin-Yuan Wang Jun-Bo Wang Min Lin Hua Zhang Chuanwen Chang National Mobile Communications Research Laboratory Southeast University Nanjing China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing China The 28th Research Institute of China Electronics Technology Group Corporation Nanjing China

ISBN: (数字)9781728150895

ISBN: (纸本)9781728150901

In this paper, a hovering unmanned aerial vehicle (UAV)-based free-space optical (FSO) serial multi-hop decode-and-forward relaying system is investigated. Considering the joint effect of atmospheric loss, atmospheric turbulence, pointing error and angle-of-arrival (AOA) fluctuation, the novel closed-form expressions of the link outage probabilities for ground-to-UAV, UAV-to-UAV, and UAV-to-ground links are derived, and the expression of the end-to-end outage probability for the UAV-based relaying system is also obtained. The asymptotic outage performance bounds for each link and the considered system are presented to reveal insights into the impact of AOA fluctuations. Based on the derived theoretical results, an optimization problem of receiver's field-of-view (FOV) is formulated to alleviate the impairment of AOA fluctuation. Numerical results show that the derived theoretical expressions are accurate to evaluate the outage performance of UAV-based FSO system. Moreover, the derived FOV can improve performance significantly.

关键词： Atmospheric modeling Optical fiber communication Adaptive optics Unmanned aerial vehicles Optical receivers Power system reliability Probability

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Editorial

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International Journal of Ad Hoc and Ubiquitous Computing 2013年第3-4期13卷 155-157页

作者： Yang, Zhen Huang, Yueh-Min Rodrigues, Joel Zhou, Liang Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing China Department of Engineering Science National Cheng-Kung University Tainan City Taiwan Instituto de Telecomunicacões University of Beira Interior Rua Marques D'Avila e Bolama 6201-001 Covilhã Portugal

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Task Classification Unloading Algorithm For Mobile Edge Computing in Smart Grid

Task Classification Unloading Algorithm For Mobile Edge Comp...

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IEEE Advanced Information technology, Electronic and Automation Control Conference (IAEAC)

作者： Ningzhe Xing Peng Wu Shen Jin Jiming Yao Zhichen Xu State Grid Jibei Electric Power Co. Ltd Beijing China Global Energy Interconnection Research Institute Co. Ltd Beijing China State Grid Laboratory of Electric Power Communication Network Technology Beijing China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology (Ministry of Education) Nanjing University of Posts and Telecommunications China

ISBN: (数字)9781728180281

ISBN: (纸本)9781728180298

With the rapid development of smart grid, the data generated by grid services are growing rapidly, and the requirements for time delay are becoming more and more stringent. The storage and computing capacity of the existing terminal equipment can not meet the needs of high bandwidth and low delay of the system at the same time. Fortunately, mobile edge computing (MEC) can provide users with nearby storage and computing services at the network edge, this can give an option to simultaneously meet the requirement of high bandwidth and low delay. Aiming at the problem of service offload scheduling in edge computing, this paper proposes a delay optimized task offload algorithm based on task priority classification. Firstly, the priority of power grid services is divided by using analytic hierarchy process (AHP), and the processing efficiency and quality of service of emergency tasks are guaranteed by giving higher weight coefficients to delay constraints and security levels. Secondly, the service is initialized and unloaded according to the task preprocessing time. Finally, the reasonable subchannel allocation is carried out based on the task priority design decision method. Simulation results show that compared with the traditional approaches, our algorithm can effectively improve the overall system revenue and reduce the average user task delay.

关键词： Simulation Delays Classification algorithms Smart grids Resource management Task analysis Edge computing

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Average Channel Capacity Analysis for Visible Light communications with Random Receivers

Average Channel Capacity Analysis for Visible Light Communic...

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International Conference on wireless communications and Signal Processing (WCSP)

作者： Xian-Tao Fu Rong-Rong Lu Sheng-Hong Lin Jin-Yuan Wang Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing China Shanghai Key Laboratory of Trustworthy Computing East China Normal University Shanghai China Key Laboratory of Opto-technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University Lanzhou China National Local Joint Engineering Research Center for Communication and Network Technologies Nanjing University of Posts and Telecommunications Nanjing China

ISBN: (数字)9781728172361

ISBN: (纸本)9781728172378

For indoor visible light communications (VLC), the receivers are usually set to be fixed ones in previous studies. However, the locations and orientations of receivers are affected by random factors in practical VLC systems. In this paper, the performance of VLC with random receivers is investigated. We consider an VLC system, which consists of a transmitter and a receiver. The main noise is additive white Gaussian noise. Two random factors (i.e., random location and random orientation) of the receiver are considered. Based on the established system model, closed-form expressions of the average channel capacity for systems with random location and random orientation are derived, respectively. Numerical results verify the accuracy of the derived theoretical expressions. Moreover, the impacts of the nominal optical intensity, the dimming target, the transmitter height and the Lambertian emission order on system performance are also discussed.

关键词： Visible light communication Optical transmitters Optical receivers Light emitting diodes Channel capacity High-speed optical techniques wireless communication

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