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arXiv 2017年

作者： Wan, Liangtian Liu, Kaihui Liang, Ying-Chang Zhu, Tong Key Laboratory for Ubiquitous Network and Service Software of Liaoning Province School of Software Dalian University of Technology Dalian116620 China National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of China Chengdu611731 China National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of China Chengdu611731 China School of Electrical and Information Engineering University of Sydney NSW2006 Australia Tianjin Institute of Computing Technology Tianjin300000 China

In this paper, an algorithm of multiple signal classification (MUSIC) is proposed for two-dimensional (2-D) direction-of-arrival (DOA) and polarization estimation of non-circular signal in three-dimensional (3-D) millimeter wave polarized large-scale/massive multiple-input-multiple-output (MIMO) systems. The traditional MUSIC-based algorithms can estimate either the DOA and polarization for circular signal or the DOA for non-circular signal by using spectrum search. By contrast, in the proposed algorithm only the DOA estimation needs spectrum search, and the polarization estimation has a closed-form expression. First, a novel dimension-reduced MUSIC (DR-MUSIC) is proposed for DOA and polarization estimation of circular signal with low computational complexity. Next, based on the quaternion theory, a novel algorithm named quaternion non-circular MUSIC (QNC-MUSIC) is proposed for parameter estimation of non-circular signal with high estimation accuracy. Then based on the DOA estimation result using QNC-MUSIC, the polarization estimation of non-circular signal is acquired by using the closed-form expression of the polarization estimation in DR-MUSIC. In addition, the computational complexity analysis shows that compared with the conventional DOA and polarization estimation algorithms, our proposed QNC-MUSIC and DR-MUSIC have much lower computational complexity, especially when the source number is large. The stochastic Cramér-Rao Bound (CRB) for the estimation of the 2-D DOA and polarization parameters of the non-circular signals is derived as well. Finally, numerical examples are provided to demonstrate that the proposed algorithms can improve the parameter estimation performance when the large-scale/massive MIMO systems are employed. Copyright © 2017, The Authors. All rights reserved.

关键词： MIMO systems

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Grasping and folding knots

Grasping and folding knots

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IEEE International Conference on Robotics and Automation

作者： Weifu Wang Devin Balkcom Anhui Province Key Laboratory of Software Engineering in Computing and Communication University of Science and Technology of China Hefei Anhui China

ISBN: (纸本)9781467380270

String stretched tightly along a sequence of fixed grasp points takes the shape of a polygonal arc. In this work, we investigate how many points are necessary and sufficient to grasp and tie arbitrary knots while maintaining tension, so that the string remains polygonal. This approach allows reasoning that is entirely geometric, which does not rely on potentially inaccurate dynamic models of the string or detailed knowledge of physical characteristics of the string. Algorithms are proposed to determine the contact locations, and generate the motions needed to tie arbitrary knots. This work shows that a number of grasp points that is linear in the number of crossings in a knot diagram is sufficient to immobilize string in a polygonal shape with the topology of an arbitrary knot, or to fold or unfold the knot from a straight configuration.

关键词： Grasping folding knots

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DFTCP: A TCP-friendly delay-based high-speed TCP variant

DFTCP: A TCP-friendly delay-based high-speed TCP variant

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International Conference on Networking and Network Applications (NaNA)

作者： Xu Zhang Naijie Gu Junjie Su Kaixin Ren Anhui Province Key Laboratory of Computing and Communication Software Hefei China Institute of Advanced Technology University of Science and Technology of China Hefei China

Due to the conservative additive increase and multiplicative decrease strategy, traditional TCP has a severe problem in utilizing bandwidth over high-speed long-distance networks. This paper proposes a delay-based congestion control algorithm, named DFTCP, for these networks. DFTCP calculates a reasonable equilibrium point for a network flow based on the estimation of the maximum size of available buffers along its network path, and adjusts the congestion window size according to the distance between the equilibrium point and the current network state. The experimental results demonstrate that, the new algorithm performs well in terms of bandwidth utilization, intra-protocol fairness and RTT fairness, and exhibits reasonable friendliness to standard TCP.

关键词： Delays Standards Packet loss Throughput Bandwidth Convergence

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Learning with only multiple instance positive bags

Learning with only multiple instance positive bags

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2016 International Joint Conference on Neural Networks, IJCNN 2016

作者： Wang, Zhigang Zhao, Zengshun Zhang, Changshui Computer and Communication Engineering School Tianjin University of Technology Tianjin Key Laboratory of Intelligence Computing and Novel Software Technology China Key Laboratory of Computer Vision and System Tianjin University of Technology Ministry of Education China College of Electronics Communication and Physics Shandong University of Science and Technology China Automation Department Tsinghua University State Key Laboratory of Intelligent Technology and Systems Tsinghua National Laboratory for Information Science and Technology China

ISBN: (纸本)9781509006199

In traditional multiple instance learning (MIL), both positive and negative bags are required to learn a prediction function. However, a high human cost is needed to know the label of each bag - positive or negative. Only positive bags contain our focus (positive instances) while negative bags consist of noise or background (negative instances). So we do not expect to spend too much to label the negative bags. Contrary to our expectation, nearly all existing MIL methods require enough negative bags besides positive ones. In this paper we propose an algorithm called 'Positive Multiple Instance' (PMI), which learns a classifier given only a set of positive bags. So the annotation of negative bags becomes unnecessary in our method. PMI is constructed based on the assumption that the unknown positive instances in positive bags be similar each other and constitute one compact cluster in feature space and the negative instances locate outside this cluster. The experimental results demonstrate that PMI achieves the performances close to or a little worse than those of the traditional MIL algorithms on benchmark and real data sets. However, the number of training bags in PMI is reduced significantly compared with traditional MIL algorithms. © 2016 IEEE.

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Evolutionary community discovery in dynamic networks based on leader nodes

Evolutionary community discovery in dynamic networks based o...

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International Conference on Big Data and Smart computing (BIGCOMP)

作者： Wenhao Gao Wenjian Luo Chenyang Bu Anhui Province key Laboratory of Software Engineering in Computing and Communication University of Science and Technology of China Hefei Anhui China University of Science and Technology of China Hefei Anhui CN

Evolutionary community discovery is a hot research topic which clusters the dynamic or temporal network. The communities detected in dynamic network should get reasonable partition for the current data while simultaneously not deviate drastically from the previous ones. In this paper, the evolutionary community discovery algorithm based on leader nodes (EvoLeaders) is proposed to cluster the dynamic network. Compared with the static community discovery algorithm based on leader nodes (the Top Leaders algorithm), experimental results over two real-world datasets demonstrate that the EvoLeaders is more suitable for dynamic scenarios.

关键词： Heuristic algorithms Clustering algorithms Current measurement Partitioning algorithms Social network services History Merging

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Exploiting trust degree for multiple-antenna user cooperation

arXiv

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arXiv 2017年

作者： Zhao, Mingxiong Ryu, Jong Yeol Lee, Jemin Quek, Tony Q.S. Feng, Suili School of Software Yunnan University Kunming China Key Laboratory in Software Engineering of Yunnan Province Department of Information and Communication Engineering Gyeongsang National University Tongyeong Korea Republic of Daegu Korea Republic of Singapore University of Technology and Design 487372 Singapore Department of Electronics Engineering Kyung Hee University Yongin-si Gyeonggi-do17104 Korea Republic of School of Electronics and Information Engineering South China University of Technology Guangzhou China

For a user cooperation system with multiple antennas, we consider a trust degree based cooperation techniques to explore the influence of the trustworthiness between users on the communication systems. For the system with two communication pairs, when one communication pair achieves its quality of service (QoS) requirement, they can help the transmission of the other communication pair according to the trust degree, which quantifies the trustworthiness between users in the cooperation. For given trust degree, we investigate the user cooperation strategies, which include the power allocation and precoder design for various antenna configurations. For SISO and MISO cases, we provide the optimal power allocation and beamformer design that maximize the expected achievable rates while guaranteeing the QoS requirement. For a SIMO case, we resort to semidefinite relaxation (SDR) technique and block coordinate update (BCU) method to solve the corresponding problem, and guarantee the rank-one solutions at each step. For a MIMO case, as MIMO is the generalization of MISO and SIMO, the similarities among their problem structures inspire us to combine the methods from MISO and SIMO together to efficiently tackle MIMO case. Simulation results show that the trust degree information has a great effect on the performance of the user cooperation in terms of the expected achievable rate, and the proposed user cooperation strategies achieve high achievable rates for given trust degree. Copyright © 2017, The Authors. All rights reserved.

关键词： Beamforming

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Performance of CO-OFDM system with RS-Turbo concatenated code

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Optoelectronics Letters 2015年第6期11卷 457-460页

作者：童峥嵘胡桂彬曹晔张卫华 Key Laboratory of Film Electronics and Communication Devices and Key Laboratory of Intelligent Computing and Novel Software Technology Tianjin University of Technology

In this paper,the RS-Turbo concatenated code is applied to coherent optical orthogonal frequency division multiplexing(CO-OFDM) ***(186,166,8) and Turbo code with code rate of 1/2 are employed for RS-Turbo concatenated *** decoding algorithms,which are Max-Log-MAP algorithm and Log-MAP algorithm,are adopted for Turbo decoding,and the iteration Berlekamp-Massey(BM) algorithm is adopted for RS *** simulation results show that the bit error rate(BER) performance of CO-OFDM system with RS-Turbo concatenated code is significantly improved at high optical signal to noise ratio(OSNR),and the iteration number is reduced compared with that of the Turbo coded ***,when the Max-Log-MAP algorithm is adopted for Turbo decoding,the transmission distance of CO-OFDM system with RS-Turbo concatenated code can reach about 400 km without error,while that of the Turbo coded system can only reach about 240 km when BER is lower than 10^(-4) order of magnitude.

关键词： OFDM系统 RS解码 Max-Log-MAP算法性能 Turbo码正交频分复用解码算法光信噪比

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Research on the transmission performance of turbo codes in DDO-OFDM system

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Optoelectronics Letters 2015年第2期11卷 134-136页

A direct detection optical orthogonal frequency division multiplexing(DDO-OFDM)system using turbo codes is built,and the transmission performance comparison between coded system and uncoded system is *** decoding algorithms,which are Log-maximum a posteriori(MAP),Max-Log-MAP and threshold Max-Log-MAP,are used in the turbo coded *** comparing three decoding algorithms,the system using Max-Log-MAP algorithm has the best bit error rate(BER)*** the transmission distance of 240 km,the uncoded system with transmission rate of 30 Gbit/s can get the BER performance at the degree of 8.93×10-3 with optical signal to noise ratio(OSNR)of24 d B,while the turbo coded system with transmission rate of 50 Gbit/s can achieve it within OSNR of 20 d B.

关键词： Bit error rate Decoding Error statistics Frequency division multiplexing Optical communication Optical signal processing Signal to noise ratio Turbo codes

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Energy-Efficient In-Memory Paging for Smartphones

Energy-Efficient In-Memory Paging for Smartphones

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作者： Zhong, Kan Liu, Duo Liang, Liang Zhu, Xiao Long, Linbo Wang, Yi Sha, Edwin Hsing-Mean College of Computer Science Chongqing University Chongqing400044 China Key Laboratory of Dependable Service Computing in Cyber Physical Society Chongqing University Ministry of Education Chongqing400044 China College of Communication Engineering Chongqing University Chongqing400044 China College of Computer Science and Software Engineering Shenzhen University Shenzhen518060 China

Smartphones are becoming increasingly energy-hungry to support feature-rich applications, posing a lot of pressure on battery lifetime and making energy consumption a non-negligible issue. In particular, dynamic random access memory (DRAM)-based main memory subsystem is a major contributor to the energy consumption of mobile devices. In this paper, we propose direct read (DR). Swap, an energy-efficient in-memory paging design to reduce energy consumption in smartphones. In DR. Swap, we adopt emerging energy-efficient nonvolatile memory (NVM) and use it as the swap area. Utilizing NVMs byte-addressability, we propose DR which guarantees zero memory copy for read-only requests when accessing a page in swap area. To better understand the energy consumption of swapping, we build an energy model to analyze the energy consumption of different paging architectures. We evaluate DR. Swap based on the Google Nexus 5 smartphone, experimental results show that our technique can reduce more than 50% energy consumption compared to DRAM backed swapping. © 2015 IEEE.

关键词： Smartphones

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Clustering time-evolving data using an efficient differential evolution 6th

Clustering time-evolving data using an efficient differentia...

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6th International Conference on Swarm Intelligence, ICSI 2015 held in conjunction with the 2nd BRICS Congress on Computational Intelligence, CCI 2015

作者： Chen, Gang Luo, Wenjian Anhui Province key Laboratory of Software Engineering in Computing and Communication School of Computer Science and Technology University of Science and Technology of China HefeiAnhui China

ISBN: (纸本)9783319204659

The previous evolutionary clustering methods for time-evolving data usually adopt the temporal smoothness framework, which controls the balance between temporal noise and true concept drift of clusters. They, however, have two major drawbacks: (1) assuming a fixed number of clusters over time;(2) the penalty term may reduce the accuracy of the clustering. In this paper, a Multimodal Evolutionary Clustering (MEC) based on Differential Evolution (DE) is presented to cope with these problems. With an existing chromosome representation of the ACDE, the MEC automatically determines the cluster number at each time step. Moreover, instead of adopting the temporal smoothness framework, we try to deal with the problem from view of the multimodal optimization. That is, the species-based DE (SDE) for multimodal optimization is adopted in the MEC. Thus the MEC is a hybrid of the ACDE and the SDE, and designed for time-evolving data clustering. Experimental evaluation demonstrates the MEC achieves good results. © Springer International Publishing Switzerland 2015.

关键词： Cluster analysis

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