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Hierarchical-Based Object Detection with Improved Locality Sparse Coding

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Chinese Journal of Electronics 2016年第2期25卷 290-295页

作者： zhu suguo DU Junping REN Nan LIANG Meiyu Beijing Key Laboratory of Intelligent Telecommunication software and Multimedia School of Computer ScienceBeijing University of Posts and Telecommunications

This paper proposes to extend the hierarchical method to be adapted to sequential frames, aiming at detecting the moving object in dynamic scenes. A novel two-layer model is proposed, in which dictionaries are learned through three different stages and the locality constrained sparse representation is improved. This leads more significant improvement for performance of both static image classification and moving object detection. The experimental results demonstrate that the proposed algorithm is efficient and robust compared with the state-of-the-art classification methods, and also able to detect moving object in the sequential frames accurately.

关键词： Hierarchical detection Sparse coding Classification Object detection

Adaptive multiple video sensors fusion based on decentralized Kalman filter and sensor confidence

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Science China(Information Sciences) 2017年第6期60卷 133-144页

作者： Qingping LI Junping DU suguo zhu Liang XU Beijing Key Laboratory of Intelligent Telecommunication Software and Multimedia School of Computer ScienceBeijing University of Posts and Telecommunications

The fusion of multiple video sensors provides an effective way to improve the robustness and accuracy of video surveillance systems. In this paper, an adaptive fusion method based on a decentralized Kalman filter(DKF) and sensor confidence is presented for the fusion of multiple video sensors. The adaptive scheme is one of the approaches used for preventing the divergence problem of the filter when statistical values of the measurement noises of the system models are not available. By introducing the sensor confidence, we can adaptively adjust the measurement noise covariance matrix of the local DKFs and thus, determine the weight of each sensor more correctly in the fusion procedure. Also, the DKF applied here can make full use of redundant tracking data from multiple video sensors and give more accurate fusion results in an efficient manner. Finally,the fusion result with improved accuracy is obtained. Experimental results show that the proposed adaptive decentralized Kalman filter fusion(ADKFF) method works well in the case of real-world video sequences and exhibits more promising performance than single sensors and comparative fusion methods.

关键词： video sensors fusion decentralized Kalman filter target tracking sensor confidence video surveillance

Robust visual tracking based on scale invariance and deep learning

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Frontiers of Computer Science 2017年第2期11卷 230-242页

作者： Nan REN Junping DU suguo zhu Linghui LI Dan FAN JangMyung LEE Beijing Key Laboratory of Intelligent Telecommunication Software and Multimedia School of Computer Science Beijing University of Posts and Telecommunications Beijing 100876 China Department of Electronics Engineering Pusan National University Busan 46241 Korea

Visual tracking is a popular research area in com- puter vision, which is very difficult to actualize because of challenges such as changes in scale and illumination, rota- tion, fast motion, and occlusion. Consequently, the focus in this research area is to make tracking algorithms adapt to these changes, so as to implement stable and accurate vi- sual tracking. This paper proposes a visual tracking algorithm that integrates the scale invariance of SURF feature with deep learning to enhance the tracking robustness when the size of the object to be tracked changes significantly. Particle filter is used for motion estimation. The co^fidence of each parti- cle is computed via a deep neural network, and the result of particle filter is verified and corrected by mean shift because of its computational efficiency and insensitivity to external interference. Both qualitative and quantitative evaluations on challenging benchmark sequences demonstrate that the pro- posed tracking algorithm performs favorably against several state-of-the-art methods throughout the challenging factors in visual tracking, especially for scale variation.

关键词： visual tracking SURF mean shift particle filter neural network

Fake Reviews Tell No Tales？ Dissecting Click Farming in Content-Generated Social Networks

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China Communications 2018年第4期15卷 98-109页

作者： Neng Li suguo Du Haizhong Zheng Minhui Xue Haojin zhu Shanghai Jiao Tong University Shanghai 200240 Chin New York University Shanghai Shanghai 200122 China

Recently, there has been a radial shift from traditional online social networks to content-generated social networks(CGSNs). Contemporary CGSNs, such as Dianping and Trip Advisor, are often the targets of click farming in which fake reviews are posted in order to boost or diminish the ratings of listed products and services simply through clicking. Click farming often emanates from a collection of multiple fake or compromised accounts, which we call click farmers. In this paper, we conduct a three-phase methodology to detect click farming. We begin by clustering communities based on newly-defined collusion networks. We then apply the Louvain community detection method to detecting communities. We finally perform a binary classification on detected-communities. Our results of over a year-long study show that(1) the prevalence of click farming is different across CGSNs;(2) most click farmers are lowly-rated;(3) click-farming communities have relatively tight relations between users;(4) more highly-ranked stores have a greater portion of fake reviews.

关键词： click farming community detec-tion content-generated social networks

太赫兹超材料吸收器的完美吸收条件与吸收特性

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中国激光 2019年第6期46卷 231-236页

作者：崔子健王玥朱冬颖岳莉莎陈素果哈尔滨理工大学工程电介质及其应用教育部重点实验室黑龙江哈尔滨150080 西安理工大学理学院陕西西安710048

提出了一种复合结构三频带太赫兹超材料吸收器,其对特定频率的入射太赫兹波呈现出完全吸收的特性。设计的超材料吸收器在入射角度达到50°时仍能保持良好的吸收特性。利用干涉理论分析了完美吸收发生的条件以及介质层介电常数对吸收频... 详细信息

提出了一种复合结构三频带太赫兹超材料吸收器,其对特定频率的入射太赫兹波呈现出完全吸收的特性。设计的超材料吸收器在入射角度达到50°时仍能保持良好的吸收特性。利用干涉理论分析了完美吸收发生的条件以及介质层介电常数对吸收频率的影响。进一步利用传输线理论结合干涉理论,分析了耶路撒冷十字短边长度对吸收特性的影响,结果表明:随着短边长度增加,吸收峰发生红移。实验结果与仿真、干涉理论、传输线理论中得到的结果吻合得较好,为今后超材料吸收器的设计提供了指导。

关键词：太赫兹技术光谱学超材料干涉传输线

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铜镍合金滑动摩擦学行为的分子动力学模拟

摩擦学学报 2023年第9期43卷 1046-1054页

作者：王权庄宿国刘秀波孟元朱正兴周安中南林业科技大学材料表界面科学与技术湖南省重点实验室湖南长沙410004 西北工业大学机电学院陕西西安710072

基于分子动力学模拟建立金刚石结构粗糙磨粒球与Ni60/10%Cu(C1)和Ni60/20%Cu(C2)铜镍合金滑动摩擦结构模型,通过探究铜镍合金在金刚石磨粒不同摩擦深度下滑动摩擦行为,结合合金的磨损形貌、磨损原子数目及分布、摩擦力和亚表面损伤对合... 详细信息

基于分子动力学模拟建立金刚石结构粗糙磨粒球与Ni60/10%Cu(C1)和Ni60/20%Cu(C2)铜镍合金滑动摩擦结构模型,通过探究铜镍合金在金刚石磨粒不同摩擦深度下滑动摩擦行为,结合合金的磨损形貌、磨损原子数目及分布、摩擦力和亚表面损伤对合金纳米尺度下磨损机理进行了研究.结果表明:在摩擦过程中,合金磨损原子首先堆积在磨粒前方,随着滑动摩擦的进行,当压入深度为10?时,磨损原子与磨粒之间黏附力较小,磨损原子流向磨痕两侧,当压入深度为20?时,磨损原子数量增加,增加的磨损原子主要堆积在磨粒前方,共同对合金进行磨损.随压入深度的增加,合金在摩擦过程中的位错密度上升,合金亚表面损伤程度提高,但在相同压入深度下,C2合金平均位错密度大于C1合金,C1合金的亚表面质量优于C2合金,这表明摩擦深度是影响合金亚表面质量的重要因素,且Cu原子数目增加会提高合金在纳米尺度下摩擦过程中亚表面损伤.

关键词：分子动力学模拟铜镍合金滑动摩擦亚表面损伤纳米摩擦

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Ti6Al4V合金激光熔覆Ti_(3)SiC_(2)增强Ni60复合涂层组织与摩擦学性能

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摩擦学学报 2021年第3期41卷 414-422页

作者：祝杨庄宿国刘秀波刘一帆柯金孟元中南林业科技大学材料表界面科学与技术湖南省重点实验室湖南长沙410004 西安航天动力研究所陕西西安710100 中国科学院兰州化学物理研究所固体润滑国家重点实验室甘肃兰州730000

为了提高Ti6Al4V合金的耐磨减摩性能,在其表面利用激光熔覆技术制备出两种不同配比的Ti3Si C2/Ni60复合涂层,分别是5%Ti_(3)SiC_(2)+Ni60(N1)和10%Ti_(3)SiC_(2)+Ni60(N2)(均为质量分数),研究了这两种涂层在室温、300和600℃下的微观组... 详细信息

为了提高Ti6Al4V合金的耐磨减摩性能,在其表面利用激光熔覆技术制备出两种不同配比的Ti3Si C2/Ni60复合涂层,分别是5%Ti_(3)SiC_(2)+Ni60(N1)和10%Ti_(3)SiC_(2)+Ni60(N2)(均为质量分数),研究了这两种涂层在室温、300和600℃下的微观组织、显微硬度、摩擦学性能表现及相关磨损机理.结果表明:涂层主要由硬质相TiC/TiB/Ti_(x)Ni_(y),γ-Ni固溶体连续相和润滑相Ti_(3)SiC_(2)组成.N1、N2涂层的显微硬度均为基体(350HV_(0.5))的3倍左右,分别为1101.90HV_(0.5)和1037.23HV_(0.5),在室温、300和600℃下的摩擦系数分别为0.39、0.35、0.30和0.41、0.45、0.44,均小于基体的摩擦系数(0.51、0.49、0.47).N1、N2涂层在室温、300和600℃下的磨损率分别为3.07×10^(-5)、1.47×10^(-5)、0.77×10^(-5)mm^(3)/(N·m)和1.45×10^(-5)、0.96×10^(-5)、0.62×10^(-5)mm^(3)/(N·m),均远小于基体[35.96×10^(-5)、25.99×10^(-5)、15.18×10^(-5)mm^(3)/(N·m)].在本文中Ti_(3)SiC_(2)提高了Ti6Al4V合金的耐磨减摩性能,使得N1涂层表现出更好的减摩性能,N2涂层表现出更好的耐磨性能.室温下,磨粒磨损、塑性变形以及轻微的黏着磨损为两种涂层的主要磨损机理;300℃时,塑性变形、氧化磨损和黏着磨损是N1涂层的对应机理,600℃时出现了三体磨粒磨损;在300和600℃时,黏着磨损、氧化磨损及磨粒磨损为N2涂层的主要磨损机理.

关键词： Ti6Al4V合金 Ti_(3)SiC_(2) 激光熔覆耐磨减摩复合涂层

端面密封材料S-07不锈钢滑动摩擦学行为的分子动力学模拟

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润滑与密封 2023年第3期48卷 141-146页

作者：王权庄宿国黄丹朱正兴刘秀波中南林业科技大学材料表界面科学与技术湖南省重点实验室湖南长沙410004 西安航天动力研究所陕西西安710100

为探究端面密封材料S-07不锈钢在不同参数下的摩擦学行为,构建纳米尺度下S-07不锈钢的摩擦磨损模型,以对偶件的压入深度和滑动速度作为变量,研究S-07不锈钢表面摩擦学性能及形貌变化。结果表明:随着摩擦相对滑动速度的增加(50、100、150... 详细信息

为探究端面密封材料S-07不锈钢在不同参数下的摩擦学行为,构建纳米尺度下S-07不锈钢的摩擦磨损模型,以对偶件的压入深度和滑动速度作为变量,研究S-07不锈钢表面摩擦学性能及形貌变化。结果表明:随着摩擦相对滑动速度的增加(50、100、150 m/s),S-07不锈钢磨损表面粗糙度降低;随着对偶件压入深度(0.3、0.6、0.9 nm)的增大,摩擦因数呈上升趋势;磨损量随压入深度增大而增大,随滑动速度上升呈下降趋势。在微观尺度上,从位错、塑性变形等角度解释了在不同磨损条件下S-07不锈钢性能变化的原因,为该材料适用摩擦工况的选择提供了理论参考。

关键词：端面密封摩擦学行为分子动力学模拟 S-07不锈钢

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大城市道路拥挤收费的仿真分析

中南公路工程 2007年第2期32卷 95-98,102页

作者：朱昕隽志才杜素果上海交通大学安泰管理学院交通运输研究所上海200052

拥挤收费是城市交通管理的有效措施之一,它可以引导和调节交通流量,达到缓解城市交通拥挤的目的。分析了上海的交通拥挤现状及其症结,通过路网服务水平模型,使用占有率与饱和度2项指标对在上海实行拥挤收费的可行性进行了仿真分析评价,... 详细信息

拥挤收费是城市交通管理的有效措施之一,它可以引导和调节交通流量,达到缓解城市交通拥挤的目的。分析了上海的交通拥挤现状及其症结,通过路网服务水平模型,使用占有率与饱和度2项指标对在上海实行拥挤收费的可行性进行了仿真分析评价,分析结果显示拥挤收费实施后,路网的占有率与饱和度明显降低,说明上海采取拥挤收费措施能够有效地控制交通出行的需求和调节车流的时空分布,从而缓解城市交通拥挤。

关键词：拥挤收费交通需求管理仿真分析