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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Jin-Hai zhang,Wei-Min Wang,Shu-Qin Wang,and Zhen-Xing Yao 1 chinese academy of Sciences,{3. of Geology and Geophysics,beijing,china. 2 chinese academy of Sciences,{3. of Tibetan Plateau Research,Key Laboratory of Continental Collision and Plateau Uplift,beijing,china. 3.Minzu University of china,{3. of Information Engineering,beijing,china.

A wide-angle propagator is essential when imaging complex media with strong lateral velocity contrasts in one-way wave-equation *** have developed a dual-domain one-way propagator using truncated Chebyshev polynomials and a globally optimized *** method increases the accuracy of the expanded square-root operator by adding two high-order terms to the traditional split-step Fourier ***,we approximate the square-root operator using Taylor expansion around the reference background ***,we apply the first-kind Chebyshev polynomials to economize the results of the Taylor ***,we optimize the constant coefficients using the globally optimized scheme,which are fixed and feasible for arbitrary velocity *** analysis and numerical experiments have demonstrated that the method has very high accuracy and exceeds the unoptimized Fourier finite-difference propagator for the entire range of practical velocity contrasts. The accurate propagation angle of the method is always about 60°under the relative error of 1%for complex media with weak,moderate,and even strong lateral velocity *** method allows us to handle wide-angle propagations and strong lateral velocity contrast simultaneously by using Fourier transform *** four 2D Fourier transforms are required for each step of 3. wavefield extrapolation,and the computing cost is similar to that of the Fourier finite-difference *** with the finite-difference method,our method has no two-way splitting error(i.e.,azimuthal-anisotropy error)for 3. cases and almost no numerical dispersion for coarse *** addition, it has strong potential to be accelerated when an enhanced fast Fourier transform algorithm emerges.

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IPv6核心路由协议及其部署的研究

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计算机科学 2004年第9期31卷 26-28页

作者：张云勇刘韵洁张智江李国杰李忠诚中国科学院计算技术研究所北京100080 中国联合通信有限公司技术部博士后科研工作站北京100032

IPv6协议由于诸多优良特性,已成为未来互联网的标准。路由协议在所有协议中有着非常关键的作用,本文讨论、比较了IPv6的主要路由协议,并且为了使得网络具有可扩展性,满足网络的短期和长期的发展需求,还阐述了运营级网络核心路由协议的... 详细信息

IPv6协议由于诸多优良特性,已成为未来互联网的标准。路由协议在所有协议中有着非常关键的作用,本文讨论、比较了IPv6的主要路由协议,并且为了使得网络具有可扩展性,满足网络的短期和长期的发展需求,还阐述了运营级网络核心路由协议的选择。

关键词：路由协议 IPv6协议网络运营可扩展性互联网部署短期

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海基拦截导弹弹道建模与仿真

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系统仿真学报 2009年第S2期21卷 89-91,96页

作者：石磊张占月装备指挥技术学院研究生管理大队北京101416 装备指挥技术学院航天装备系北京101416

拦截导弹弹道仿真是海基导弹防御系统建模与仿真的一个重要部分,以美国海基拦截导弹的研究为背景,分析了拦截导弹的特性,建立了弹道仿真模型,给出了发射诸元参数的计算方法和基本仿真流程,并进行了三维数据仿真。结果表明建立的模型和... 详细信息

拦截导弹弹道仿真是海基导弹防御系统建模与仿真的一个重要部分,以美国海基拦截导弹的研究为背景,分析了拦截导弹的特性,建立了弹道仿真模型,给出了发射诸元参数的计算方法和基本仿真流程,并进行了三维数据仿真。结果表明建立的模型和采用的算法具有合理性,能够反映拦截导弹的主要性能,能够应用于进一步的仿真研究。

关键词：拦截弹道弹道仿真导弹建模弹道模型

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面向对象的设计方法在IP计费管理软件上的应用

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计算机工程与应用 2002年第20期38卷 141-143页

作者：傅川张国清侯桂文中国科学院计算技术研究所北京100080

随着互联网高速发展,网络基础资源的有偿使用已成为必须解决的问题。文章从面向对象的分析和设计方法出发,详细分析了IP计费管理中存在的问题,提出了适用于静态和动态IP环境的计费框架,并以此实现了一个IP计费管理系统。一方面提高了开... 详细信息

随着互联网高速发展,网络基础资源的有偿使用已成为必须解决的问题。文章从面向对象的分析和设计方法出发,详细分析了IP计费管理中存在的问题,提出了适用于静态和动态IP环境的计费框架,并以此实现了一个IP计费管理系统。一方面提高了开发效率,节约了开发成本;另一方面增强了计费软件的重用性。

关键词：面向对象 IP计费管理软件计算机网络网络管理软件开发

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Skyway:Accelerate Graph Applications with a Dual-Path Architecture and Fine-Grained Data Management

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Journal of Computer Science & technology 2024年第4期39卷 871-894页

作者： Mo Zou Ming-Zhe zhang Ru-Jia Wang Xian-He Sun Xiao-Chun Ye Dong-Rui Fan Zhi-Min Tang institute of computing technology Chinese Academy of SciencesBeijing 100190China University of chinese academy of Sciences Beijing 100049China institute of Information Engineering Chinese Academy of SciencesBeijing 100045China Department of Computer Science Illinois Institute of TechnologyChicagoIL 60616U.S.A.

Graph processing is a vital component of many AI and big data ***,due to its poor locality and complex data access patterns,graph processing is also a known performance killer of AI and big data *** this work,we propose to enhance graph processing applications by leveraging fine-grained memory access patterns with a dual-path architecture on top of existing software-based graph *** first identify that memory accesses to the offset,edge,and state array have distinct locality and impact on *** then introduce the Skyway architecture,which consists of two primary components:1)a dedicated direct data path between the core and memory to transfer state array elements efficiently,and 2)a data-type aware fine-grained memory-side row buffer hardware for both the newly designed direct data path and the regular memory hierarchy data *** proposed Skyway architecture is able to improve the overall performance by reducing the memory access interference and improving data access efficiency with a minimal *** evaluate Skyway on a set of diverse algorithms using large real-world *** a simulated fourcore system,Skyway improves the performance by 23.on average over the best-performing graph-specialized hardware optimizations.

关键词： graph application computer architecture memory hierarchy

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一种类Spreadsheet结构的信息汇聚方法

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计算机科学 2010年第5期37卷 134-138页

作者：魏永山韩燕波孙忠林张峰陈欣山东科技大学信息科学与工程学院青岛266510 中国科学院计算技术研究所北京100083

SpreadSheet样式的数据操作具有很好的可用性,但在SpreadSheet结构中如何表示并操纵XML数据以及如何使用复制、粘贴、移动等简单操作表示复杂的XQuery查询是两个难点问题。提出一种基于XML模式的操作表示方法,将复杂的XQuery查询语句分... 详细信息

SpreadSheet样式的数据操作具有很好的可用性,但在SpreadSheet结构中如何表示并操纵XML数据以及如何使用复制、粘贴、移动等简单操作表示复杂的XQuery查询是两个难点问题。提出一种基于XML模式的操作表示方法,将复杂的XQuery查询语句分解为XML模式上的粘贴节点、移动节点等操作,从而可以表示XQuery语言的核心语句FLOWR。在Spreadsheet结构中将XML模式显示为嵌套表格,用户在嵌套表格上的操作转换为XML模式上的操作。使用该方法可以构造多数据源的XQuery查询,并实现了概念验证的原型系统。与当前流行的XQuery查询构造工具相比较,原型系统更适合于无编程经验的最终用户构造XQuery查询。

关键词： Spread Sheet XQuery 信息集成信息资源汇聚

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Study on a harvester navigation and yield analysis system

Study on a harvester navigation and yield analysis system

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The First International Conference on Computers and computing Technologies in Agriculture

作者： YUAN YANWEI zhang XIAOCHAO~* HU XIAOAN institute of Mechatronics technology and Application {3. academy of Agricultural Mechanisation Sciences Box 25 No.1 Beishatan Dewai St beijing 100083.PR china

＜正＞A system attached to a small harvester and able to navigate was studied to analyse distribution information on wheat yield while *** this system,a balance-based yield flowmeter was built to detect the weight of moving *** transform methods were employed to reduce errors. GPS receivers and GIS technology were used to report coordinates and the corresponding yield data, based on which a yield map could be displayed synchronously,and the harvester track could be displayed on a digital map drawn by the system.A meter was programmed to accumulate and display the reaped area on a screen with data from a GPS receiver and header *** showed that the system can detect wheat weight with an error less than 3.5%,and it can create a digital map rapidly and display the harvester’s track as it *** reaped area was synchronously shown with errors less than 2.4%.

关键词： coordinate transform digital maps GIS GPS harvester meter harvester track yield map

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一种基于Rough集的属性值约简算法

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计算机工程与应用 2003年第31期39卷 48-51页

作者：胡斐张峰筠刘少辉上海体育学院体育管理系上海200438 中国科学院计算技术研究所智能信息处理重点实验室北京100080

文章将Rough集理论应用于不同类型的决策表(一致决策表和不一致决策表)的约简,给出了广义决策、决策规则的一致程度、属性值重要性等定义,在此基础上提出了一种基于Rough集的属性值约简算法。该算法不仅能得到更为简洁的决策规则,而且... 详细信息

文章将Rough集理论应用于不同类型的决策表(一致决策表和不一致决策表)的约简,给出了广义决策、决策规则的一致程度、属性值重要性等定义,在此基础上提出了一种基于Rough集的属性值约简算法。该算法不仅能得到更为简洁的决策规则,而且能保持决策规则的一致程度不变。实例分析表明该算法是可行的。

关键词： Rough集决策表值核值约简

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The brain functional and structural mechanism in coal mining survivors with PTSD after two and ten months

The brain functional and structural mechanism in coal mining...

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中国神经科学学会第四次会员代表大会暨第七届全国学术会议

作者： Cai-Lan HOU~(1,2),Ling-Jiang LI~2,Yan zhang~2,Jun LIU~2,Zhong HE~2,Wei-Hui LI~2,Kun Wang~3.Yong LIU~3.Gao-Lang GONG~3.Ni SHU~3.Meng LIANG~3.Tian-Zi JIANG~3.1 Guangdong Provincial Mental Health institute,Guangdong Provincial Hospital,Guanzhou 510120,china 2 Mental Health institute,the Second Xiangya Hospital,Central South University,Changsha 410011,china 3.Medical Imaging and computing National laboratory of Pattern Recognition institute of Automation,chinese academy of Sciences, beijing 100080,china

＜正＞Objective We sought to characterize the brain responses and structure of patients with acute severe post traumatic stress disorder（PTSD）,and investigate the neurocircuit of *** subjects would be reevaluated at ten months after the coal mining accident for the longitudinal *** Twenty four individuals with acute severe PTSD resulting from the mining accident and 24 subjects exposed to the mining accident without PTSD underwent functional magnetic resonance imaging（fMRI） while performing the emotional counting stroop,the symptom provocation and trauma related short-term memory recall *** three functional tasks were block *** duration of every series was 5 min and 12 *** dimension imaging（3.） and diffusion tensor magnetic resonance imaging（DTI） examinations were *** fMRI and MRI tests were finished,we offered to them free psychological and medication *** the subjects were reassessed and diagnosed for PTSD symptoms at the ten months from the mining accident,and the PTSD patients who were diagnosed for the first time received fMRI and MRI tests for the second time. The data of structural and functional MRI were dealt with statistical parametric mapping（SPM2） ***（1） During the emotional counting stroop,PTSD subjects showed diminished responses in bilateral anterior cingulate gyrus, right inferior frontal gyrus,left superior temporal gyrus and etc,compared with Non-PTSD controls at the two months after the *** subjects showed enhanced responses in left medial frontal gyrus,right middle frontal gyrus,right cingulate gyrus,left parahippocampal gyrus compared with Non-PTSD controls at ten months after the *** PTSD subjects at ten months were compared with at two months by paired *** superior frontal gyrus,bilateral middle frontal gyrus,right cingulate gyrus,left parahippocampal gyrus had enhanced responses.（2） During symptom provocation paradigm,PTSD subjects showed

关键词： coal mining accident acute severe PTSD fMRI 3. DTI

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Leakage and wear characteristics of carbon seals for aero-engines

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chinese Journal of Aeronautics 2022年第11期35卷 389-400页

作者： guoqing LI Shen zhang Zhong KANG Yanfeng zhang Xingen LU Junqiang ZHU institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing 100190China School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBejing 102206China

Experimental investigation has been performed to study the leakage and wear characteristics of carbon seal working at high circumferential speed. To expand the scope of application, two newly designed carbon seals were compared: #1 Carbon Seal(CS1) with the inner diameter of13. mm and including 4 segments, #2 Carbon Seal(CS2) with the inner diameter of 212 mm and including 6 segments. Air leakage tests were firstly conducted in the Medium-speed Seal Test Rig. The pressure ratio changed from 1.04 to 2.02 with the rotating speed varying from 0 to183.0 r/min. Of paramount concern was the durability test, including 3.0 h running time accumulated by three different working conditions, which was separately implemented on each carbon *** morphology variation of the friction surface, wear and leakage were recorded. Results indicated that the leakage monotonously increases with the pressure ratio and decreases with the rotating speed. Comparing with CS1, more typical features exist on the friction surface of CS2, which are generated by more severe wear. Continually, leakage characteristics deteriorate. Furthermore, fitted formula has been educed for the life prediction of carbon seal, which could provide some supports for aero-engine design.

关键词： Aero-engine Carbon seal Durability test Leakage Rotating Wear

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