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Distribution network topology reconstruction method based on lasso and its supplementary criterions 10th

Distribution network topology reconstruction method based on...

10th International Conference on Security, Privacy and Anonymity in Computation, Communication and Storage, SpaCCS 2017

作者： Li, Xiaoyu Li, Shufang Li, Wenqi Tian, Shiming Pan, Mingming Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing100876 China State Grid Henan Electric Power Company Jinshui District Zhengzhou450052 China China Electric Power Research Institute Haidian District Beijing100192 China

ISBN: (纸本)9783319723945

In order to solve the problem of topology reconstruction in distribution network, a new data driven algorithm is proposed, which uses only the timing voltage to reconstruct the un-loopy and loopy distribution network topology without the prior knowledge. Firstly, the topology reconstruction problem is transformed into a convex optimization problem, and the Lasso regularization method is utilized to obtain a sparse correlation coefficient matrix (CCM), which represents the connectivity of the topology. Secondly, the "And" rule is employed to reduce the redundancy of CCM. And then the criterion of the voltage correlation analysis model is adopted as a supplemental criterion to reduce the error rate of CCM. Finally, the topology reconstruction of the distribution network is realized based on the accurate CCM. Simulation results show that the algorithm has high accuracy, universality and low computational complexity. © Springer International Publishing AG 2017.

关键词： Convex optimization

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Dual-layer efficiency enhancement for future passive optical network

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Science China(Information Sciences) 2016年第2期59卷 172-184页

作者： Yuefeng JI Xiaoxiong WANG Shizong ZHANG Rentao GU Tonglu GUO Zhaozhi GE State Key Lab of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications

Ever-increasing demands on bandwidth compel us to improve the bandwidth utilization of access networks. It is more important to enhance the efficiency of passive optical networks(PON) than other access technologies, as they are the primary solutions to various access scenarios. To satisfy the demands of improved bandwidth efficiency, we propose a dual-layer(data link layer and network layer) efficiency enhancement scheme for future PON system. Under this architecture, a data-link-layer flexible coding scheme is introduced to extend the downstream link throughput, and a network-layer centralized active queue management(AQM) scheme is introduced to increase bandwidth efficiency. Both of these technologies are designed to suit the future centralized cooperative control mode. The results of an experimental demonstration of the network coding PON scheme reveal the efficiency of the proposed architecture. The results of simulations show that the centralized AQM scheme has a positive influence on queuing delay and jitter. To the best of our knowledge, this is the first time that a data link layer mechanism and a network layer policy have been integrated to provide high efficiency and quality of service in access networks.

关键词： passive optical network bandwidth efficiency network coding active queue management centralized control

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Expected Q-learning for Self-Organizing Resource Allocation in LTE-U with Downlink-Uplink Decoupling

Expected Q-learning for Self-Organizing Resource Allocation ...

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European Wireless 2017;23th European Wireless Conference

作者： Ye Hu Richard MacKenzie Mo Hao Beijing Laboratory of Advanced Information Network Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications BT TSO Tsinghua SEM Advanced ICT Lab

ISBN: (纸本)9781509038442

Exponentially growing demand on mobile data facilitates the need to increase spectrum efficiency and also to gain access to additional spectrum bands. LTE-U provides a way for LTE service to be provided, in some regulatory areas, using a combination of licensed and unlicensed spectrum. In this paper, we consider the resource allocation problem in LTE-U networks with downlink-uplink decoupling (DUDe) technique. Here, the spectrum allocation problem is formulated as a game theoretic model which incorporates user association, spectrum allocation, and load balancing. We propose a decentralized expected Q-learning algorithm to solve this game. Using the proposed algorithm, the base stations can autonomously choose their optimal spectrum allocation schemes based on only limited information from the networks. It is shown that the proposed algorithm converges to a stationary mixed-strategy distribution which constitutes a mixed strategy Nash equilibrium for the studied game. Simulation results show the proposed Q-learning algorithm yields up to 12.7% and 51.1% improvement in terms of total rate, compared to traditional Q-learning and nearest neighbor algorithms, respectively. Furthermore, it is shown that the proposed Q-learning algorithm always converges to a mixed Nash equilibrium, and need 19% less time to coverage compared to traditional Q-learning.

关键词： Estimation Field programmable gate arrays OFDM Modulation Filtration Clocks Signal processing algorithms

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Zone Coordinates: A New Coordinate system

Zone Coordinates: A New Coordinate System

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2017 17th IEEE International Conference on Communication Technology (ICCT 2017)

作者： Zehua Gao Mingjing Zhu Yuxi Tan School of Information and Communication Engineering Beijing Laboratory of Advanced Information NetworksBeijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

Coordinates systems include rectangular coordinate systems, cylindrical coordinate systems, and spherical coordinate systems, among others. In three-dimensional rectangular coordinate systems, "x = 2" defines a plane, "x = 2,y = 3" defines a line, and "x = 2, y = 3, z = 1" defines a ***, traditional coordinates systems are represented by the combination of point, line, and plane. In the real world,every object or field occupies a certain volume, even atoms or protons. We present a new coordinate system, called the zone coordinate system, that gives the position of an entire object or field. The zone coordinate system is more in line with reality. It can be applied in every field that requires a location-based application.

关键词： rectangular coordinate point-line coordinates zone coordinate

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A Dynamic Multiuser Detection Scheme for Uplink SCMA system

A Dynamic Multiuser Detection Scheme for Uplink SCMA System

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2017 17th IEEE International Conference on Communication Technology (ICCT 2017)

作者： Yuxi Tan Zehua Gao Siyan Guo Feng Gao School of Information and Communication Engineering Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

As one of nonorthogonal multiple access techniques for the fifth generation mobile communications, sparse code multiple access（SCMA） can provide a better link performance than other schemes in different network scenarios. However, SCMA employs message passing algorithm（MPA） as its receiver decoding scheme which leads to higher computing complexity and restricts it’s application to low latency networks. Based on this, a dynamic message passing algorithm（DMPA） is presented in this paper for reducing calculation complexity of original MPA. In DMPA, reliability of variable node can be calculated by the pseudo posterior probability after predetermined iterations, and then messages are propagated merely in subgraph of original factor graph which can result in a significant reduction in complexity. Simulation results show that DMPA can reduce decoding complexity about 37% than MPA with negligible bit error rate（BER） degradation.

关键词： SCMA（Sparse Code Multiple Access） MPA（Message Passing Algorithm） BER（Bit error rate） complexity

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Consistent-estimated eigenvalues based cooperative spectrum sensing for dense cognitive Small Cell network

Consistent-estimated eigenvalues based cooperative spectrum ...

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IEEE International Conference on Communications Workshops, ICC

作者： Meng Zhao Caili Guo Chunyan Feng Shuo Chen Beijing Laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China

ISBN: (纸本)9781509015269

In this paper, we consider the spectrum sensing problem of detecting a primary signal of a macro cell in a cognitive radio network by employing multiple dense small cell base stations. In consideration of the number of cooperative small cells (sample dimension) is comparable to the number of sample (sample size) due to the dense deployment of small cells, sample covariance matrix is no more a good estimator of statistical covariance matrix. A consistent-estimated eigenvalues based cooperative spectrum sensing (CEE-CSS) algorithm is proposed by utilizing consistent estimators of eigenvalues which are proven to be consistent when the sample dimension goes to infinity at the same rate as sample size. Effect of the eigenvalue splitting condition on sensing performance of the CEE-CSS is analyzed through simulations. Further simulation results present that the proposed CEE-CSS enables better sensing performance than a maximum-minimum eigenvalue detection based on oracle approximating shrinkage estimator (OAS-MME).

关键词： Sensors Eigenvalues and eigenfunctions Covariance matrices Microprocessors Computer architecture Market research Estimation

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A Spatial Dimming Scheme Based on Transmit Antenna Selection for Multiuser MISO VLC systems

A Spatial Dimming Scheme Based on Transmit Antenna Selection...

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International Conference on Communications Workshops

作者： Zhen Feng Caili Guo Yang Yang Chunyan Feng Beijing Laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications China Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications China

ISBN: (纸本)9781509015269

The multi-user multiple-input single-output (MU-MISO) visible light communications (VLC) system, which can serve multi-users simultaneously, have been widely studied in recent years. Dimming control is one of the main topics in VLC systems. In this paper, we proposed a novel transmit antenna selection based spatial dimming (TAS-SD) scheme for zero forcing (ZF) precoded MU-MISO VLC systems. By taking full advantage of the channel state information at both the transmitter and the users, the proposed TAS-SD scheme can combine the precoding and transmit antenna selection (TAS) technique together, and effectively improves the performance of dimmable MU-MISO systems. Simulation results show that the proposed TAS-SD scheme has significant bit error-ratio performance gains over the conventional analog dimming (AD) scheme at various dimming proportions and user positions. These advantages make it a promising candidate dimming scheme for ZF precoded MU-MISO VLC systems.

关键词： Multiuser MISO VLC

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Analyzing human mobility and social relationships from cellular network data

Analyzing human mobility and social relationships from cellu...

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International Conference on network and Service Management

作者： Zheng Liu Yuanyuan Qiao Siyan Tao Wenhui Lin Jie Yang BUPT Beijing Key Laboratory of Network System Architecture and Convergence and Beijing Laboratory of Advanced Information Networks Beijing China Technology Research Institute Aisino Corporation Beijing China

Due to geographic and social constraints, human mobility shows a high degree of temporal and spatial regularity. More recently, emerging data tagged with geographical information can be used to study human mobility patterns. People usually spend most of their time at a few key important locations, such as home and work places. And for users with a certain social connection-co-workers or co-life, they often stay at the same locations. In this paper, firstly, we use an algorithm to identify important locations. After that, we find that the similarity between the two trajectories is closely related to their proximity in the location-based social network, where users having the same important locations are connected. In order to embody social contacts in mobility, for hourly variations in mobility similarity, we apply unsupervised clustering method to identify four categories of social ties. Finally, we further propose the unsupervised method and supervised method to predict which new links will develop in a social location-based network. We believe our finding can contribute to urban planning especially in areas of functional zone, transportation infrastructure deployment and mobile network facilities development.

关键词： Social network services Base stations Correlation Mobile computing Trajectory Cellular networks

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AP LOAD BALANCE BASED HANDOVER IN SOFTWARE DEFINED WiFi systemS 5

AP LOAD BALANCE BASED HANDOVER IN SOFTWARE DEFINED WiFi SYST...

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2016 5th IEEE International Conference on network Infrastructure and Digital Content(IC-NIDC 2016)

作者： Nahida Kiran Yin Changchuan Zaid Akram Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

ISBN: (纸本)9781509012473

In existing wireless systems it's hard for an operator to change the network strategy under heavy load due to its proprietary and inflexible hardware based *** paper explores the concept of software defined networking(SDN) in wireless *** access point(AP) load balance based handover scheme in SDN WiFi systems is proposed for overlapping wireless local area network cells to take efficient handover based on AP *** implemented the proposed load balancing handover scheme in Mininet-WiFi emulator which could handle the APs from a centralized controller and help the test client determine how and when to connect with the right AP and take efficient handover based on AP *** interface is added with the station,client's traffic is tested at different positions and improved throughput for mobile clients is *** results show that total network throughput is enhanced after a successful handover.

关键词： Software defined networking Wireless networks Mini-net Mininet-WiFi

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Research and Analysis of Browsing Habits of New Media Audiences on the Chinese Campus

Research and Analysis of Browsing Habits of New Media Audien...

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2017 2nd International Conference on Wireless Communication and network Engineering(WCNE 2017)

作者： Dong-jun HAN Qiu-jian LV Jie YANG Center for Data Science Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture and ConvergenceBUPT Institute of Information Engineering Chinese Academy of Sciences

Audience research is such a hit nowadays, and always has been based on web logs modeling. However, the content data of articles has not been considered yet. So, this paper clusters the ordered word vectors of an article to analyze audiences browsing habits of Chinese campus. This paper first obtains the contents and page views of articles from We Chat official accounts of several Chinese campuses. Then, it analyzes the audiences by clustering the ordered word vectors of the articles they have been read. To do so, the articles are first converted into a word vector model through Jieba word segmentation and word2vec, and then TF-IDF is applied for weight sequencing. Finally, the distances between articles are obtained by calculating the mean sum of square of the distances between words. Also, we cluster contents according to their topics and obtain many meaningful results. This paper provides a new method of audience analysis based on semantic, which can simplify the manual classification process of articles, and provide more comprehensive analysis conclusions. Moreover, these analysis results are useful for the strategy of content production and precious marketing.

关键词： Campus new media Audience analysis Word vector Article clustering

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