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Microstructure and mechanical properties of Nanoscale Cu/Nb Multilayers

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Microstructure and mechanical properties of Nanoscale Cu/Nb ...

第18届国际真空大会

作者： X.Y. Zhua b J.T. Luoa G. Chena F. Zenga and F. Pana* aLaboratory of Advanced Materials department of Materials Science and engineering tsinghua university beijing 100084 People’s Republic of china bNational Key Lab for Remanufacturing Academy of Armored Forces engineering beijing 100072 People’s Republic of china

Nanoscale Cu/Nb multilayers with layer thickness ranging from 2.5 nm to 20.0 nm were prepared by evaporation deposition. The microstructure, hardness and creep behavior of the multilayers were investigated by X-ray diffraction, transmission electron microscopy, scanning electron microscopy and nanoindentation. The strength values obey the CLS model as the layer thickness decreases to 6.5 nm. After that, it reaches a peak value of 3.28 GPa at the smallest layer thickness of 2.5 nm, which agrees well with the value predicted by the atomic simulations based on crossing of dislocations across interfaces mechanism. The stress exponent determined by dimensional analysis varies from 3.75 to 7.35 and decreases with the decreasing layer thickness. Meanwhile, the total creep depth augments with the decreasing layer thickness. It indicates that the creep process is dominated by dislocation glide-climb mechanism and the decreases in layer thickness will promote the climb process because of the effective diffusion paths provided by interfaces.

关键词： Cu/Nb multilayers Nanoindentation Microstructure Hardness Creep

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对象意识与自我意识及其客观性:一个再思考

学习与探索 2002年第1期 7-13页

作者：杨耕陈志良北京师范大学哲学系中国人民大学哲学系北京100875 北京100872

人的意识是对象意识和自我意识的统一。意识之所以二重化为对象意识与自我意识 ,其根源在于实践活动的对象性与自觉的目的性。从结构上看 ,对象意识与自我意识的根本区别是他反性和自反性 ;从功能上看 ,对象意识指向外部世界 ,自我意识... 详细信息

人的意识是对象意识和自我意识的统一。意识之所以二重化为对象意识与自我意识 ,其根源在于实践活动的对象性与自觉的目的性。从结构上看 ,对象意识与自我意识的根本区别是他反性和自反性 ;从功能上看 ,对象意识指向外部世界 ,自我意识指向人的内部世界 ;从层次上看 ,对象意识是对客体的一级反映 ,自我意识则是二级反映。客观性是认识中的普遍性、规律性。现代科学的发展突出了自我意识与客观性的矛盾 ,而解决这一矛盾需要辩证思维

关键词：马克思主义认识论对象意识自我意识客观性

Fusing Global and Regional Features for Image Classification

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Fusing Global and Regional Features for Image Classification

2009中国控制与决策会议

作者： Xiaohong Hu~(1,2),Xu Qian~2 1.School of Information and Management Science,Henan Agricultural university,Zhengzhou,450002,china 2.School of mechanical Electronic and Information engineering,china university of Mining and Technology,beijing,100083,china

＜正＞This paper presents a novel approach to image classification based on the fusion of global and regional features,which are helpful to describe image semantics to classification,in which vague sets for positive and negative evidences is applied to analyze and optimize the decisions obtained by *** integrating two sides of multiple classification decisions,the classification is optimized and synthesized,thus the processing and results will be both powerful and *** results show that the performance of the classification is greatly improved.

关键词： vague set decision fusion support vector machine

The New Architecture for High Performance Signal Processing System

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The New Architecture for High Performance Signal Processing ...

第七届国际信号处理会议

作者： Bin He Xiaonan Wang (department of Electronic engineering beijing university of Chemical Technology beijing china 100029) Email: hebinhello@***

Based on the RapidIO protocol, the new architecture, which is based on the peer-to-peer, for high performance multi-DSP (Digital Signal Processor) signal processing system is introduced. The new ar

关键词： VLSI FPGA RapidIO protocol and Signal processing

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位置灵敏探测器的数据采集系统设计与实现

数据采集与处理 1999年第3期14卷 334-337页

作者：庞文宁阮存军尚仁成马骏清华大学物理系北京100084 清华大学继续教育学院北京100084

介绍位置灵敏探测器数据采集系统的设计与实现。该系统由两片或三片微通道板、位置读出阳极以及数字化处理系统模块构成，具有较高的数据获取速度和灵活性。在微型计算机的支持下，系统的每个数据获取通道相当于一个微机多道分析器，可... 详细信息

介绍位置灵敏探测器数据采集系统的设计与实现。该系统由两片或三片微通道板、位置读出阳极以及数字化处理系统模块构成，具有较高的数据获取速度和灵活性。在微型计算机的支持下，系统的每个数据获取通道相当于一个微机多道分析器，可以根据实验需要的通道数很方便地组合数据获取通道，特别适用于一维或二维的位置探测。通过对系统性能进行测试，得到了很好的结果。目前，该数据获取系统已经成功地应用于（ｅ，２ｅ）实验。

关键词：位置灵敏探测器 (e,2e)实验数据采集原子电离

PHSICAL MODELLING AND PROCESSING OF Ti-6Al-4V ELI

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Acta Metallurgica Sinica(English Letters) 2000年第2期13卷 606-610页

作者： C.P. Chou, S.C. Wang, C.C. Chang and W.R. Wang 1) department of mechanical engineering, National Chiao Tung university Hsinchu, Taiwan 300, china 2) Materials Research Laboratories, Industrial Technology Research Institute Chutung, Taiwan 310, china

Titanium has been widely used as the implant materials of joint prostheses. This paper simulates the microstructures of the hot forged titanium knee joint component by physical modeling. Ti-6Al-4V ELI were deformed by GLEEBLE 2000 hot deforma- tion simulator in compression mode to determine the hot workability, in the range of 900 to 1100℃, with the strain rates between 0.05 to 5 s^(-1). Test results derived from specimens processed by on-cooling test and on-heating test were compared, thereby estimating the effect due to thermal history. The forging process of Ti-6Al-4V ELI tibial base plate of knee joint prostheses was design based on the workability data obtained.

关键词： physical modeling hot workability processing map,compression test hot forging

FEATURE SOLID MODELING TOOL SYSTEM:FSMTS

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Computer Aided Drafting,Design and Manufacturing 1992年第1期3卷 58-66页

作者： DUAN Weiyin ZHOU Ji YU Jun department of mechanical engineering Shanghai Jiao Tong university,Shanghai,P.R.chinadepartment of mechanical engineering Huazhong university of Science and Technology,Wuhan,P.R.china

In conformity with the principle of Design for Manufacture,feature-based design strate- (?)es have been *** the“feature”is relevant to the“macro process plan”and“macro NC programs”,obviously,“feature”is beyond the power of conventional solid ***- less,substantial breakthrough has not been made in the solid modeling field,except“feature at- taching”or“feature recognizing”methods have been taken *** this paper,the theory, concepts,system architecture,and algorithm principles of solid modeling tool system have been *** practice of Feature Solid Modeling Tool System (FSMTS) developed at Huazhong university has proved that the tool may be a new foundation of Feature-Based Design.

关键词： CAD/CAM feature solid modeling tool

ARCHITECTURE SINGULARITY ANALYSIS FOR A CLASS OF PARALLEL MANIPULATORS

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ARCHITECTURE SINGULARITY ANALYSIS FOR A CLASS OF PARALLEL MA...

2006年中国机械工程学会年会暨中国工程院机械与运载工程学部首届年会

作者： LI Luyang*, WU Hongtao*, ZHU Jianying* *department of Mechatronic engineering, Nanjing university of Aeronautics and Astronautics, Nanjing 210016, china department of mechanical engineering, Yangzhou university, Yangzhou 225009, china

The present investigates the architecture singularity of a class of parallel manipulators. In general, singularity of parallel manipulators can be categorized into inverse and forward kinematic singul

关键词： Parallel manipulator architecture singularity jacobian matrix.

A Stochastic Growth Model of Multi Macro-economic System

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A Stochastic Growth Model of Multi Macro-economic System

第七届中国不确定系统年会

作者： Gao-Rong Ning~(1*) Xian-Yuan Wu~1 Kai-Yuan Cai~2 Tao Liang~3 1 School of Mathematical Sciences,Capital Normal university,beijing,100037,china 2 department of Automatic Control,beijing university of Aeronautics and Astronautics,beijing,100083,china 3 Information engineering College,beijing Capital Normal university,beijing,100037,china

＜正＞In this paper we propose a simple model of multi-organizations to analyze the dynamic behaviors of macro-economic *** this model,three mechanisms are included:1) congeneric firms are mainly competition against each other,and inhomogeneous firms are mainly synergic with each other;2) the Gibrat’s Law of Proportionate Effect is followed, that is,the expected value of the growth rate of a business firm is proportional to its current size in its own industry and 3) new firms continually enter the *** find that the firm size distribution in its own industry displays heavy tails or power-law,where the power is determined by the quotient of demand factor and supply factor of this *** contrasts the Gaussian distribution predicted by Gibrat’s law of proportionate effect.

关键词： Gibrat’s law power law firms size distribution demand factor dynamical economic systems