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Fast approximate matching of binary codes with distinctive bits

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Frontiers of Computer Science 2015年第5期9卷 741-750页

作者： Chenggang clarence YAN Hongtao XIE Bing zhang Yanping MA Qiong DAI Yizhi LIU Institute of Information Engineering Chinese Academy of Sciences National Engineering Laboratory for Information Security Technologies Beijing 100093 China Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China Department of Automation Tsinghua University Beijing 100083 China School of Physics Beijing Institute of Technology Beijing 100081 China School of Information Science and Engineering Ocean University of China Qingdao 266100 China School of Computer Science and Engineering Hunan University of Science and Technology Xiangtan 411201 China

Although the distance between binary codes can be computed fast in Hamming space, linear search is not practical for large scale datasets. Therefore attention has been paid to the efficiency of performing approximate nearest neighbor search, in which hierarchical clustering trees （HCT） are widely used. However, HCT select cluster centers randomly and build indexes with the entire binary code, this degrades search performance. In this paper, we first propose a new clustering algorithm, which chooses cluster centers on the basis of relative distances and uses a more homogeneous partition of the dataset than HCT has to build the hierarchical clustering trees. Then, we present an algorithm to compress binary codes by extracting distinctive bits according to the standard deviation of each bit. Consequently, a new index is proposed using compressed binary codes based on hierarchical decomposition of binary spaces. Experiments conducted on reference datasets and a dataset of one billion binary codes demonstrate the effectiveness and efficiency of our method.

关键词： binary codes approximate nearest neighbor search hierarchical clustering index

Memory bandwidth optimization of SpMV on GPGPUs

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Frontiers of Computer Science 2015年第3期9卷 431-441页

作者： Chenggang clarence YAN Hui YU Weizhi XU Yingping zhang Bochuan CHEN Zhu TIAN Yuxuan WANG Jian YIN key Lab of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China Institute of Microelectronics Tsinghua University Beijing 100084 China Automation Department Tsinghua University Beijing 100084 China State key Laboratory of Computer Architecture Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China State Grid Information & Communication Company of Hunan EPC Changsha 410007 China Department of Computer Shandong University Weihai 250101 China

It is an important task to improve performance for sparse matrix vector multiplication （SpMV）, and it is a difficult task because of its irregular memory access. Gen- eral purpose GPU （GPGPU） provides high computing abil- ity and substantial bandwidth that cannot be fully exploited by SpMV due to its irregularity. In this paper, we propose two novel methods to optimize the memory bandwidth for SpMV on GPGPU. First, a new storage format is proposed to exploit memory bandwidth of GPU architecture more effi- ciently. The new storage format can ensure that there are as many non-zeros as possible in the format which is suitable to exploit the memory bandwidth of the GPU. Second, we pro- pose a cache blocking method to improve the performance of SpMV on GPU architecture. The sparse matrix is partitioned into sub-blocks that are stored in CSR format. With the block- ing method, the corresponding part of vector x can be reused in the GPU cache, so the time to access the global memory for vector x is reduced heavily. Experiments are carried out on three GPU platforms, GeForce 9800 GX2, GeForce GTX 480, and Tesla k40. Experimental results show that both new methods can efficiently improve the utilization of GPU mem- ory bandwidth and the performance of the GPU.

关键词： GPGPU performance tuning SpMV cacheblocking memory bandwidth

Robot Interaction Force Estimation Using an Adaptive Sliding Mode Observer

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Instrumentation 2019年第2期6卷 8-20页

作者： Yanjun WANG Yunfei zhang Shujun GAO clarence WDE SILVA ViWiSTAR Technologies Ltd. VancouerCanadaV6T lZ4 Dept.of Mechanical Engineering University of British ColumbiaVancouwerCanadaV6T lZ4

In constrained motion control of a robot,the interaction force is an important variable,which directly describes the state of *** is required in a number of algorithms for interaction ***,the interaction force has to be measured by force ***,there are inherent limitations with force sensors,such as the cost,sensing noise,limited bandwidth,and the difficulty of physical location at the required place,which is *** the present paper,the interaction force is estimated by using high order sliding mode *** adaptive version of a high order sliding mode observer is developed to robustly reconstruct the interaction *** results are given to show the effectiveness of the developed algorithms.

关键词： Constrained Motion Robot Manipulator Adaptive Estimation Sliding Mode Observer Dynamic Identification

应用神经网络和统计模型预测大豆生长发育阶段

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作物学报 2009年第2期35卷 341-347页

作者：张久权张凌霄张明华 WATSON clarence 中国农业科学院烟草研究所山东青岛266101 Delta Research and Extension Center Mississippi State UniversityStoneville 38776MSUSA Department of Land Air and Water ResourcesUniversity of CaliforniaDavis 95616CAUSA Oklahoma State University Stillwater 74078-6009OKUSA

预测大豆的物候期对指导大豆生产、安排农事活动等具有重大意义。本研究构建了一种简单有效的预测模型,使大豆种植者能够较准确地预测大豆各生育阶段的具体日期。试验地位于美国密西西比Delta研究推广中心(经度:90°55'W,纬度:33°25'N... 详细信息

预测大豆的物候期对指导大豆生产、安排农事活动等具有重大意义。本研究构建了一种简单有效的预测模型,使大豆种植者能够较准确地预测大豆各生育阶段的具体日期。试验地位于美国密西西比Delta研究推广中心(经度:90°55'W,纬度:33°25'N)。试验进行了5年,前4年(1998—2001)数据构建模型,第5年(2002)的数据验证模型。为简化模型,杂草、病虫害、干旱等干扰因素被优化排除。采用逐步回归(SR)、神经网络(ANN)以及内插法构建模型。营养(V-stage)和生殖(R-stage)生长阶段分别建模。结果表明,通过播种日期(PD)和从播种到某阶段的相对平均天数能很准确地预测营养生长各阶段的具体日期;可通过播种日期和成熟期组数值(MG)准确预测生殖生长各阶段的具体日期。3种方法中,神经网络所构建的模型准确度最高,具有较好的推广应用价值。

关键词：大豆生长期成熟期组神经网络模拟播种日期物候学

Robust Impedance Control of Robots Using an Adaptive Interaction Force Observer

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Instrumentation 2019年第4期6卷 2-13页

作者： Yanjun WANG Yunfei zhang Shujun GAO clarence W.DE SILVA ViWiSTAR Technologies Ltd. CanadaV6T 1Z4 Dept.of Mechanical Engineering The University of British ColumbiaCanadaV6T 1Z4

For robot interaction control,the interaction force between the robot and the manipulated object or environment should be *** control is a type of interaction ***,in impedance control,the dynamic relationship between the interaction force and the resulting motion is *** order to control the impedance of a mechanical system,typically,the interaction force has to be *** to the inherent limitations of direct force sensing at the interaction site,in the present work,the interaction force is observed using robust *** particular,to enhance the accuracy of impedance control,a first order sliding mode impedance controller is designed and incorporated in the present *** advantage over positionbased interaction control algorithms is demonstrated through *** results are given to show the effectiveness of the proposed algorithms.

关键词： Interaction Control Impedance Control Neural Networks Sliding Mode Observer Sliding Mode Control

Visual Avoidance of Collision with Randomly Moving Obstacles through Approximate Reinforcement Learning

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Instrumentation 2019年第3期6卷 59-66页

作者： Yunfei zhang Yanjun WANG Haoxiang LANG Ying WANG clarence W.DE SILVA ViWiStar Technologies Ltd. Shenzhen China 518103 Mechanical Engineering Department University of Ontario Institute of TechnologyOshawaCanada LIG 0C5 Department of Mechatronics Engineering at kennesaw State University MariettaGeorgia30060USA Department of Mechanical Engineering The University of British ColumbiaVancouverCanada V6T 1Z4

In this research work,a hierarchical controller has been designed for an autonomous navigation robot to avoid unexpected moving obstacles where the state and action spaces are *** proposed scheme consists of two parts:1)a controller with a high-level approximate reinforcement learning(ARL)technique for choosing an optimal trajectory in autonomous navigation;and 2)a low-level,appearance-based visual servoing(ABVS)controller which controls and execute the motion of the robot.A novel approach for path planning and visual servoing has been proposed by the combined system *** characteristics of the on-board camera which is equipped on the robot is naturally suitable for conducting the reinforcement learning *** the ARL controller,the computational overhead is quite low thanks to the fact that a knowledge of obstacle motion is not *** developed scheme has been implemented and validated in a simulation system of obstacle *** is noted that findings of the proposed method are successfully verified by obtaining an optimal robotic plan motion strategy.

关键词： Approximate reinforcement learning Robotic obstacle avoidance Appearance-based visual servoing

安徽宣城矿集区长山铅锌多金属矿床成矿流体特征及成因

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矿床地质 2023年第4期42卷 791-810页

作者：王静张达玉黄家龙孟翔张飞侯舒雅易洪 WHITE Noel clarence 合肥工业大学资源与环境工程学院安徽合肥230009 华东冶金地质勘查研究院安徽合肥230088 华东冶金地质勘查局812地质队安徽铜陵244008

长山铅锌多金属矿床位于长江中下游成矿带宣城矿集区东北部,文章在对该矿床开展详细的地质调查和岩相学研究基础上,对代表性矿化蚀变矿物(石英、方解石)开展了流体包裹体测温、激光拉曼光谱和氢、氧、碳稳定同位素分析。长山铅锌多金属... 详细信息

长山铅锌多金属矿床位于长江中下游成矿带宣城矿集区东北部,文章在对该矿床开展详细的地质调查和岩相学研究基础上,对代表性矿化蚀变矿物(石英、方解石)开展了流体包裹体测温、激光拉曼光谱和氢、氧、碳稳定同位素分析。长山铅锌多金属矿床矿化蚀变组合从早到晚可以分为矽卡岩-氧化物阶段、早硫化物阶段和晚硫化物阶段。矿物流体包裹体温度和盐度测算显示,长山矿床的成矿流体温度和盐度从矽卡岩-氧化物阶段(315~382℃,w(NaCl)_(eq)为14.04%~16.24%)→早硫化物阶段(220~347℃,w(NaCl)_(eq)为4.49%~15.86%)→晚硫化物阶段(163~306℃,w(NaCl)_(eq)为1.40%~11.10%)逐渐降低。石英和闪锌矿中包裹体的δD和δ^(18)O值分别为-89.5‰~-67.8‰和-3.2‰~7.62‰,方解石中δ^(13)C和δ^(18)O值分别是-6.8‰~-1‰和10.6‰~17.1‰,同位素特征指示长山矿床的成矿流体为岩浆水与海相碳酸盐中富含有机质流体混合,从早硫化物阶段到晚硫化物阶段,成矿流体中岩浆水比例逐渐降低。长山铅锌多金属矿床矿石矿物的沉淀分别受降温和沸腾作用(早硫化物阶段)、降温和外来流体混合作用(晚硫化物阶段)的制约。区域对比显示,宣城矿集区具有矽卡岩型铅锌多金属矿床的找矿潜力。

关键词：地球化学成矿流体激光拉曼光谱氢、氧、碳同位素铅锌矿床宣城矿集区

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敕封之城--大连

大连大学学报 2018年第2期39卷 22-27页

作者：邹静(译) 张帅(译) 克拉伦斯·克里大连大学英语学院辽宁大连116622 大连大学东北亚研究院辽宁大连116622 不详

沙俄于1898年3月27日逼迫清政府签订《旅大租地条约》,攫取到远东常年不冻港。沙皇尼古拉二世于1899年8月11日发布大连自由港的敕令,标志着大连对外开埠并实行自由港制度,随即全力进行大连城市的建设。该译文的原文就是摘自1903年4月《S... 详细信息

沙俄于1898年3月27日逼迫清政府签订《旅大租地条约》,攫取到远东常年不冻港。沙皇尼古拉二世于1899年8月11日发布大连自由港的敕令,标志着大连对外开埠并实行自由港制度,随即全力进行大连城市的建设。该译文的原文就是摘自1903年4月《Scribners Magazine》上的一篇实地调查报告~①,文中的几张照片是在1902年末拍摄的,文中处处洋溢着作者对俄国的经营建设和繁荣景象的赞赏与夸耀之情。但是需要指出的是,虽然大连自开埠建市之后才开启了近代化历程,但却是在沙俄等西方资本主义列强不平等压迫下的畸形发展。旅大地区的同胞为此付出了惨痛的代价与牺牲;同时,沙俄不遗余力地经营大连是为了方便其进行商品输入和原料掠夺,是其在远东积极推行侵略扩张政策,与帝国主义列强争霸世界东方的产物。

关键词：大连港中东铁路西伯利亚殖民扩张

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丁香新品种‘宇攀’

园艺学报 2024年第7期51卷 1711-1712页

作者：刘建斌张炎北京农学院园林学院北京102206

欧洲丁香新品种‘宇攀’是从欧洲丁香品种‘Downfield’与‘clarence Dvan Zandt’的杂交后代中选育出来的新品种。重瓣,小花密度高、裂片浅紫色(RHS,Purple group N75B),具有较高的观赏价值。花期晚,在北京平原地区4月20日进入始花期,5... 详细信息

欧洲丁香新品种‘宇攀’是从欧洲丁香品种‘Downfield’与‘clarence Dvan Zandt’的杂交后代中选育出来的新品种。重瓣,小花密度高、裂片浅紫色(RHS,Purple group N75B),具有较高的观赏价值。花期晚,在北京平原地区4月20日进入始花期,5月1—5日进入末花期。该品种适应性强,耐旱、抗寒、较耐水淹,宜在华北及东北大部分地区栽植。

关键词：欧洲丁香品种