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Research on Discharging Mechanism of Powder Mixed EDM

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武汉理工大学学报 2006年第S2期28卷 417-422页

作者： WANG Yuangang ZHAO Fuling (Key Laboratory for precision and Non.traditional Machining technology of Ministry of Education,Dalian university of technology,Dalian 116024,china Key Laboratory for precision and Non-traditional Machining technology of Ministry of Education Dalian University of TechnologyDalian 116024China

This paper presents investigations on discharging mechanism in powder mixed *** analyzing the inception, growth of electrical tree and the ignition of discharges in liquid filled gap,the whole discharging process is *** is explored that the reason of modification of ignition behaves by adding fine particle powders of metal or semiconductor to the working liquid.

关键词： PMEDM electrical tree discharge breakdown mechanism

A Novel CAPP System Based on SML for Variant Design of Process Planning

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武汉理工大学学报 2006年第S3期28卷 820-823页

作者： ZHAO Haibin~1 WANG Junying~1 ZHANG Min~2 (1.department of precision Instruments & Mechanology,Tsinghua university,Beijing 100084,china, 2.department of Mechanical Equipment & Control Engineering,Beijing university of science and technology,Bejing 100083,china) department of precision Instruments & Mechanology Tsinghua UniversityBeijing 100084China department of Mechanical Equipment & Control Engineering Beijing University of Science and TechnologyBejing 100083 China

The production model of“multi-specification and low-quantity”is becoming the main trend of manufacturing *** a key activity in the manufacturing chain,traditional computer aided process planning(CAPP)system fails to adapt to the production model of ***,a novel method for variant design of process planning was proposed to develop CAPP system based on Tabular Layouts of Article Characteristics(Sach-Merk Leisten in German and SML for short). With the support of standard database of master process planning documents which are developed by parameterization technique, and instance process planning for special product(instance product)can be generated automatically by the sub-system of variant de- sign of process ***,a CAPP system was developed for process design of rotor of steam turbine to validate the feasibil- ity and applicability of the method.

关键词： CAPP variant design SML master process planning documents(DocMPP) parameterization

Microstructure Characteristic of In-situ Ti/TiC Composites

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Journal of Materials science & technology 2001年第1期17卷 103-104页

作者： Bo YANG Beijing institute of Aeronauticul Materials, Beijing 100095, china Erlin ZHANG Yunxue JIN Zhaojun ZHU and Songyan ZENG National Key Lab. of precision Hot Processing of Metals, Harbin institute of technology, Harbin 150001, china Beijing Inst Aeronaut Mat Beijing 100095 Peoples R China Harbin Inst Technol Natl Key Lab Precis Hot Proc Met Harbin 150001 Peoples R China

TiC reinforced titanium composites has been produced with different Al content and C content by XDTM. The results have shown that TiC particles are of two different morphologies f coarse dendritical primary TiC and short bar-shape eutectic TiC. Al content has great effects on the morphology of TiC. With the increasing of Al content, the morphology of primary TiC changes from coarse developed dendrite into short bar-shape or plate--shape TiC with 35%Al. Meanwhile, the structure of the matrix changes from single Ti to Ti and Ti3Al, and to Ti3Al and TiAl. However, the C content has no influence on the microstructure of matrix. When the C content is less than 1.2%, the dendrite TiC disappears and only short bar-shape or plate-shape TiC exists in the composites. In addition, the effect of he3t treatment on the morphology of TiC has also Studied.

关键词： TiC Microstructure Characteristic of In-situ Ti/TiC Composites

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狭缝衍射中的偏振效应

物理学报 1993年第12期42卷 2019-2023页

作者：谢建平陈风华任宝瑞明海牛亚平李川奇大圆成夫中国科学技术大学物理系合肥230026 中国科学技术大学精密机械系合肥230026 日本东京大学工学部

在狭缝的夫琅和费衍射中,由振动平行和垂直于缝边的偏振光的衍射条纹得到的缝宽值不同。本文介绍这种偏振效应的实验结果,并用边界衍射波对其物理原因进行分析,理论与实验结果符合很好。

关键词：夫琅和费衍射狭缝衍射偏振

A sensitive method of determining optic axis azimuth based on laser feedback

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Chinese Physics B 2013年第12期22卷 272-275页

作者：吴云张鹏陈文学谈宜东 The State Key Lab of precision Measurement technology and Instrument Department of Precision Instruments Tsinghua University

A sensitive method to determine the optic axis azimuth of the birefringence element is presented, which is based on laser feedback. The phase difference between the two intensities in birefringence feedback changes with the angle between the optic axis of the birefringence element and laser original polarization. The phase difference is highly sensitive to the relative position of the optic axis and the laser original polarization. This method is used to highly precisely determine the optic axis azimuth, and is able to distinguish between the fast axis and the slow axis of the birefringence element. Theoretical analysis and experimental results are both demonstrated.

关键词： laser feedback optic axis differential method phase difference

Intelligent Control on Hot Strip Coiling Temperature

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 147-150页

作者： Heping Liu Yanlong Zhao(Information Engineering School, university of science and technology Bejing, Beijing 100083, china)(Handan Iron & Steel (Group) Co, Handan 056015, china) Information Engineering School University of Science and Technology Beijing Beijing 100083 China Handan Iron and Steel (Group) Co. Handan 056015 China

A new intelligent control scheme for hot strip coiling temperature is presented. In this scheme, the prediction mode1 of finishing temperature and the presetting model of main cooling zone are establish based on BP neural network, the feed-forward open-loop control model of main cooling zone is constructed based on T-S fuzzy neural network, a new improved structure of T-S fuzzy neural network is developed, and the feedback close-loop control model of precision cooling zone is obtained based on fuzzy control. The effectiveness of the proposed scheme has been demonstrated by computer simulation with a satisfactory result.

关键词： coiling temperature control laminar cooling fuzzy control neural network, fuzzy neural network

Data fusion techniques for incomplete measurement of trajectory

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Chinese science Bulletin 2001年第8期46卷 627-630页

作者： ZHU Jubodepartment of Mathematics & System science, National university of Defense technology, Changsha 410073, china department of Mathematics & System science National University of Defense Technology Changsha China

This paper focuses on data processing for incomplete measurement of trajectory (IMT) in aerospace measurement and control. The IMT means that the principal equipment loses the measured data during some intervals so that trajectory parameters (position, velocity, etc.) cannot be determined independently. Based on a joint model for trajectory estimation with reduced parameter, a fusion way is put forth by making full use of measured data from auxiliary equipment with lower precision. In the superposition intervals of measurement between principal and auxiliary equipment, the technique of diagnosing and estimating system errors is applied to improving the estimate precision of trajectory parameters (TP) and determining the precision after data fusion. In practical test, this method operates so successfully that it can not only provide complete TP but improve their precision remarkably. Meanwhile, this way is also applicable to other problems of incomplete measurement.

关键词： incomplete measurement of trajectory data fusion re- duced parameter model error diagnose.

Large area mold fabrication for the nanoimprint lithography using electron beam lithography

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science china(Technological sciences) 2010年第1期53卷 248-252页

作者： CHU JinKui1,2,MENG FanTao1,2,HAN ZhiTao1,2 & GUO Qing1,2 1 Key Laboratory for Micro/Nano technology and System of Liaoning Province,Dalian university of technology,Dalian 116024,china 2 Key Laboratory for precision and Non-traditional Machining technology of Ministry of Education,Dalian university of technology,Dalian 116024,china 1. Key Laboratory for Micro/Nano technology and System of Liaoning Province Dalian University of Technology Dalian 116024 China2. Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of Technology Dalian 116024 China

The mold fabrication is a critical issue for the development of nanoimprint lithography as an effective low-cost and mass production *** paper describes the fabrication process developed to fabricate the large area nanoimprint molds on the silicon *** optimization of e-beam exposure dose and pattern design is *** overlayer process is developed to improve the field stitching accuracy of e-beam exposure,and around 10 nm field stitching accuracy is *** means of the optimization of the e-beam exposure dose,pattern design and overlayer process,large area nanoimprint molds having dense line structures with around 10 nm field stitching accuracy have been *** fabricated mold was used to imprint commercial imprinting resist.

关键词： nanoimprint lithography mold fabrication electron beam lithography

Design of a 6 DOF Input Device in Telerobotics and Virtual Reality

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Journal of Systems Engineering and Electronics 2002年第2期13卷 36-44页

作者： Peng Gang, Huang Xinhan, Xiong Chunshan & Wang MinControl science and Engineering department, Huazhong university of science and technology, Wuhan 430074, P.R. china(Received June 6,2001) Control science and Engineering department Huazhong University of Science and Technology Wuhan 430074 P. R. China

The pincipl of a 6 DOF (degress of freedom) input device using ultrasonic distance measurement is presented in this paper. The system employs the method of measuring the time of flight. In addition, some techniques, including automatic gain control, self-adaptive variable threshold and temperature compensation, are also used to improve precision. Then, the positions and orientation of the input device can be calculated by the method of spatial analytic geometry. Meanwhile, commands from the 3-D input device are detected and carried out. The validity and precision of the input device are verified by the experiment in a robot system. The proposed device not only can be used for end effector position and orientation measurement in telerobotics, but also can be an interactive device in virtual reality systems, such as helmet tracking, viewpoint navigation and object manipulation.

关键词： Degrees of freedom (mechanics) Three dimensional Ultrasonic applications Virtual reality