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21st International Conference on Telecommunications, ICT 2014

作者： Min, Zhao Muqing, Wu Qian, Hu Shiping, Di Panfeng, Zhou Xiangbing, Zeng Shuyun, Ge Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing 100876 China Design Section of Communication CRSCD Bejing 100073 China

ISBN: (纸本)9781479951413

The increasing interest drawn to LTE system requires the analysis of train-ground communication channel. By the approval of the Ministry of Railways of China, extensive and practical measurements are performed on Harbin-Dalian railway with a speed up to 370 km/h. Both large-scale and small-scale fading characteristics are specified. Firstly, path loss and shadowing effect are evaluated based on the hierarchical two-hop network structure. Compared with classical models, the proposed channel model is more applicable in the special viaduct scenarios. Channel characteristics, such as channel impulse response, power delay profile, K-factor, delay spread and Doppler spectrum are parameterized and reported. The in-depth analysis of these statistical channel data is from the perspectives of geographical position and relative antenna height. In particular, a new stage-wise K-factor model is investigated and developed. Combined with the cumulative distribution function of the RMS delay spread and the number of paths, they illustrate the distance-dependent and antenna height-dependent variances of the channel. Finally, the two-dimensional integrated channel models are first proposed to give a comprehensive description of broadband mobile channel in high-speed railway scenario. All these informative results promote the evaluation and verification of broadband communication system on High-Speed Railway. © 2014 IEEE.

关键词： Antennas

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Experimental demonstration of distributed QoT-aware optical path adjustment in SDON

Experimental demonstration of distributed QoT-aware optical ...

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Asia Communications and Photonics Conference, ACPC 2014

作者： Hou, Yanfang Li, Hui Liu, Yuze Zhao, Wei Ji, Yuefeng State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications No.10 Xi Tu Cheng Road Beijing100876 China Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications China

Based on OpenFlow technology, a link quality equalizer is proposed. Distributed QoTaware optical path adjustment scheme is experimentally demonstrated. It will be a novel optical path adjustment solution to large-scal... 详细信息

ISBN: (纸本)9781557528520

关键词： Photonics

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A Topology-Cognitive Algorithm Framework for Virtual network Embedding Problem

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China Communications 2014年第4期11卷 73-84页

作者： HUANG Tao LIU Jiang CHEN Jianya LIU Yunjie State Key Laboratory of Networking and Switching Technology Beijing University of Post and Telecommunications Beijing 100876 China Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing 100876 China

The virtual network embedding/mapping problem is an important issue in network virtualization in Software-Defined networking(SDN).It is mainly concerned with mapping virtual network requests,which could be a set of SDN flows,onto a shared substrate network automatically and *** researches mainly focus on developing heuristic algorithms for general topology virtual *** practice however,the virtual network is usually generated with specific topology for specific ***,it is a challenge to optimize the heuristic algorithms with these topology *** order to deal with this problem,we propose a topology-cognitive algorithm framework,which is composed of a guiding principle for topology algorithm developing and a compound *** compound algorithm is composed of several subalgorithms,which are optimized for specific *** develop star,tree,and ring topology algorithms as examples,other subalgorithms can be easily achieved following the same *** simulation results show that the topology-cognitive algorithm framework is effective in developing new topology algorithms,and the developed compound algorithm greatly enhances the performance of the Revenue/Cost(R/C) ratio and the Runtime than traditional heuristic algorithms for multi-topology virtual network embedding problem.

关键词： network virtualization software- defined networking virtual network embedding topology-cognitive

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Joint optimization for base station density and user association in energy-efficient cellular networks

Joint optimization for base station density and user associa...

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International Symposium on Wireless Personal Multimedia Communications (WPMC)

作者： Lu An Tiankui Zhang Chunyan Feng SICE Beijing Key Laboratory of Network System Architecture and Convergence Beijing China

ISBN: (纸本)9781479964123

In the research of green networks, considering the base station (BS) density from the perspective of energy efficiency is very meaningful for both network deployment and BS sleeping based power saving. In this paper, we optimize the BS density for energy efficiency in cellular networks by the stochastic geometry theory and optimize the user association matrix by the Quantum Particle Swarm Optimization (QPSO). On one hand, we model the distribution of base stations and user equipment (UE) as spatial Poisson point process (PPP). Based on such model, we derive the closed-form expressions of the average achievable data rate, the network energy consumption and the network energy efficiency with respect to the network load. Then, we optimize the BS density for network energy efficiency maximization by adopting the Newton iteration method. On the other hand, we build a user association matrix to present the connection state between BSs and UEs, and then optimize it by QPSO. Our study reveals that we can improve the network energy efficiency by switching on/off proportion of the BSs according to the network load. The simulation results validate the theoretical analysis, and show that when the right amount of BSs is deployed according to the network load, the network energy efficiency can be maximized and the maximum energy efficiency is a fixed value once the network parameters are given.

关键词： Energy efficiency Wireless communication Simulation Fading Mathematical model Energy consumption Optimization

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User cooperative erasure recovery in E-MBMS based on network coding

User cooperative erasure recovery in E-MBMS based on network...

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10th International Conference on Wireless Communications, networking and Mobile Computing (WiCOM 2014)

作者： Wenting Gao Jianjun Hao Yijun Guo Beijing Key Laboratory of Network System Architecture and Convergence BUPT China

ISBN: (纸本)9781510804166

Recent years wireless networks have witnessed an explosive growth in enhanced multimedia broadcast and multicast service (eMBMS). Scalable video coding (SVC) streaming is a mainstream coding in eMBMS. In this paper we present a novel eMBMS user cooperative erasure recovery mechanism based on network coding where SVC streaming and layer network coding are broadcasted by source node. Local cooperative repair together with network coding is used to save total overhead of links and reduce the retransmission times, for purpose of improving Quality of Service (QoS) of video streaming. The simulation results show that the number of retransmissions declines a lot through our mechanism. Local user cooperation saves link overhead as much as 55% when sender disseminates SVC streaming. Combining with layer network coding, the overhead can also be reduced about 17%.

关键词： Erasure Recovery network Coding SVC User Cooperation eMBMS network coding Static VAr compensators Quality of service Streaming

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No-reference video quality assessment via feature learning

No-reference video quality assessment via feature learning

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作者： Xu, Jingtao Ye, Peng Liu, Yong Doermann, David Language and Media Processing Laboratory University of Maryland College Park United States Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications China SONY US Research Center United States

ISBN: (纸本)9781479957514

In this paper, we propose a novel 'Opinion Free' (OF) No-Reference Video Quality Assessment (NR-VQA) algorithm based on frame-level unsupervised feature learning and hysteresis temporal pooling. The system consists of three components: feature extraction with max-min pooling, frame quality prediction and temporal pooling. Frame level features are first extracted by unsupervised feature learning and used to train a linear Support Vector Regressor (SVR) for predicting quality scores frame by frame. Frame-level quality scores are then combined by temporal pooling to obtain a single video quality score. We tested the proposed method on the LIVE video quality database and experimental results show that without training on human opinion scores the proposed method is comparable to state-of-the-art NR-VQA algorithms. © 2014 IEEE.

关键词： Quality control

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network Virtualization Based Seamless networking Scheme for Fiber-Wireless （FiWi） networks

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China Communications 2014年第5期11卷 1-16页

作者： DAI Qinglong ZOU Jianfeng SHOU Guochu HU Yihong GUO Zhigang Beijing Laboratory of Network System Architecture and Convergence School of Information and Communication EngineeringBeij ing University of Posts and Telecommunications Beijing 100876 China

In order to reduce cost and complexity,fiber-wireless(FiWi) networks emerge,combining the huge amount of available bandwidth of fiber networks and the flexibility,mobility of wireless ***,there is still a long way to go before taking fiber and wireless systems as fully integrated *** this paper,we propose a network visualization based seamless networking scheme for FiWi networks,including hierarchical model,service model,service implementation and dynamic bandwidth assignment(DBA).Then,we evaluate the performance changes after network virtualization is *** for nodes,bandwidth for links and overheads leaded by network virtualization are *** performance of our proposed networking scheme is evaluated by simulation and real implementations,*** results show that,compared to traditional networking scheme,our scheme has a better performance.

关键词： fiber-wireless networks network virtualization service future network

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Adaptive ABS Configuration Scheme with Joint Power Control for Macro-Pico Heterogeneous networks

Adaptive ABS Configuration Scheme with Joint Power Control f...

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IEEE Vehicular Technology Conference

作者： Hao Zhou Hailun Xia Caili Guo Rui Han Yaguang Wu Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

ISBN: (纸本)9781479944484

In Heterogeneous network (HetNet), reasonable resource allocation has attracted extensive attention. To allocate the resource more effectively, we propose a novel algorithm from the perspective of both time domain and power domain. On the one hand, we propose an adaptive Almost Blank Subframe (ABS) configuration scheme to dynamically match the network resources with the real-time load. On the other hand, we propose a utility function of macrocells' power control and a corresponding scheduling scheme to make a tradeoff between the two-tier macro-pico networks and protect the victim users as well. The existence of the optimal solution to the problem is proved, and Differential Evolution (DE) is applied to find the optimal solution. system level simulation results show that the proposed algorithm can not only enhance the load balance between macrocell and picocell, but also provide a great improvement on the performance of edge users with little overall throughput cost.

关键词： Heterogeneous networks Resource allocation Adaptive ABS configuration Joint power control Scheduling

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ANALYSIS OF network NODE BEHAVIOR BASED ON MAPREDUCE

ANALYSIS OF NETWORK NODE BEHAVIOR BASED ON MAPREDUCE

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2014 IEEE 3rd International Conference on Cloud Computing and Intelligence systems

作者： Gang He Peng Yang Xiaochun Wu Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

With the widespread popularity and rapid development of Internet,the network is becoming more *** of network node behavior can be crucial for network management and service *** this paper,we conduct the detailed measurement analysis of the network node（NN） traffic characteristics based on a large-scale data set collected from an enterprise network traffic monitoring device,which is deployed at the entry of enterprise network covering the Guangdong province in *** analyze the distribution of NN traffic volume and visitor *** discuss the rank of NN in terms of traffic volume distribution and visitor number distribution,which follows power law ***,we illustrate the traffic characteristics of NN in terms of visitor *** handle the problem of big data processing,we make use of Hadoop framework and MapReduce programming model to analyze huge traffic data,which handles a large collection data efficiently and quickly for scalable storage and ***,in this paper,we propose a network traffic analysis method based on MapReduce in enterprise internet.

关键词： NN enterprise internet traffic volume visitor number MapReduce big data

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PERFORMANCE MODELING AND OPTIMIZATION OF MAPREDUCE PROGRAMS

PERFORMANCE MODELING AND OPTIMIZATION OF MAPREDUCE PROGRAMS

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2014 IEEE 3rd International Conference on Cloud Computing and Intelligence systems

作者： Jinsong Yin Yuanyuan Qiao Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

MapReduce is a developer-friendly framework that encapsulates the underlying complexities of distributed *** is increasingly being used across enterprises for advanced data analytics,business intelligence,and data mining *** there are two questions bothering Hadoop users:how to improve the performance of MapReduce workloads,and how to estimate the time needed to run a MapReduce *** this paper,we provide some performance optimization techniques on the premise of workload *** the cluster achieving the best performance,we further propose a modeling method to help Hadoop users estimate the execution time of MapReduce *** evaluation,typical benchmarks are utilized to evaluate the accuracy of our techniques.

关键词： MapReduce Workload characterization Performance optimization Time modeling

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