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3D Evaluation Method of Cutting Surface Topography of Carbon / Phenolic (C/Ph) Composite

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Journal of Wuhan university of technology(Materials science) 2011年第3期26卷 459-463页

作者：周鹏 Key Laboratory for precision and Non-traditional Machining technology of Ministry of Education Dalian University of Technology

3D evaluation method of cutting surface topography for C/Ph composites was *** cutting surface was measured by Talyscan 150,using 3D non-contact *** the results of 2D and 3D roughness evaluating for C/Ph composite and Duralumin,the 2D evaluation method of the cutting surface topography of C/Ph composite loses a lot of information,the characteristics of the surface topography of C/Ph composite can be comprehensively and authentically evaluated only by 3D evaluation ***,3D amplitude and spatial parameters were adopted to evaluate the *** results show that： the topography of the C/Ph composite is anisotropic,there are more valleys in the machined surface of C/Ph than that of duralumin,and there are not obvious feeding textures for C/Ph,which indicates the machining mechanism is different from the *** conclusion,the topography of the C/Ph composite cutting surface is anisotropic;the cutting surface of C/Ph composite needs 3D evaluation method.

关键词： C/Ph composite surface topography 3D evaluation method

SURFACE ROUGHNESS PREDICTION MODEL FOR ULTRAprecision TURNING ALUMINIUM ALLOY WITH A SINGLE CRYSTAL DIAMOND TOOL

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Chinese Journal of Mechanical Engineering 2002年第2期15卷 153-156,176页

作者： Wang Hongxiang Li Dan Dong shen precision Engineering Research Institute, Harbin Institute of technology, Harbin 150001, china precision Engineering Research Institute Harbin Institute of Technology Harbin 150001China ***

A surface roughness model utilizing regression analysis method is developedfor predicting roughness of ultra-precision machined surface with a single crystal diamond tool. Theeffects of the main variables, such as cutting speed, feed, and depth of cut on surface roughnessare also analyzed in diamond turning aluminum alloy. In order to predict the optimum cuttingconditions during process planning. A lot of experimental results show that the model can predictthe surface roughness effectively under a certain cutting conditions.

关键词： Surface roughness Regression analysis Diamond turning Diamond tool

The Optical Characteristics of the Acousto-optic Tunable Filter with the Equivalent Point

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Chinese Journal of Lasers 2002年第2期11卷 55-60页

作者： XU Kexin NI Yong XUE Bin JIANG Chengzhi HU Xiaotang( State Key Laboratory of precision Measuring technology and Instruments, Tianjin university, Tianjin 300072, china) Tianjin university State Key Laboratory of Precision Measuring Technology and Instruments 天津 300072

In this paper, the interaction curves of acoustic and optical waves in a non-collinear AOTF (acousto-optic tunable filter) cell under the parallel-tangent momentum matching condition are analyzed systematically. A new theory of equivalent point for AOTF design is put forward. The wavelength characteristics and the wavelength resolution of two diffraction beams with equivalent point design in AOTF are emphatically analyzed. The optical characteristics at δ = 0 (ideal case) and δ≠0 (real case) are also discussed. The advantages of the AOTF with equivalent point design include high wavelength resolution, more quantitative energy and larger incident angle aperture.

关键词： equivalent point momentum matching AOTF TeO2

WEB-BASED REQUIREMENT SURVEY SYSTEM FOR MASS CUSTOMIZATION

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WEB-BASED REQUIREMENT SURVEY SYSTEM FOR MASS CUSTOMIZATION

Temporal and spatial variations of δ^(15)N and δ^(18)O for atmospheric N_2O above the oceanic surface from Shanghai to Antarctica

2005年中国机械工程学会年会

作者： ZHOU Ziqiang, PAN Yi, LI Mujun, SHAN Liguan ( Mechanical department, Changshu Institute of technology,Changshu, 215500 department of precision machinery, university of science & technology of china, hefei, 230026)

＜正＞This paper presents a web-based survey system which is used for the Mass Customization oriented product family development. The framework of the system is illustrated. The implementation and application technology of the system is also described. The approach of develop product family based on the statistic analyzed data is discussed.

关键词： mass customization requirement survey product family

来源： cnki会议评论

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science china Earth sciences 2008年第6期51卷 899-910页

作者： ZHU RenBin1, LIU YaShu1, XU Hua2, MA Jing2 & SUN LiGuang1 1 Institute of Polar Environment, university of science and technology of china, hefei 230026, china 2 State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil science, Chinese Academy of sciences, Nanjing 210091, china 1. Institute of Polar Environment University of Science and Technology of China Hefei 230026 China 2. State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210091 China

During the 22nd Chinese Antarctic Research Expedition (chinaRE-22), the atmospheric gas samples above the oceanic surface and near the surface were collected on the track for the scientific ship "Xuelong" and on Millor Peninsula of eastern Antarctica, respectively, using the Tedlar gas bags. Every day the sampling times were 10:00 and 22:00 (local time), respectively. In the laboratory, high-precision measurement of the isotopic compositions for N2O in these gas samples was conducted using Thermo Finnigan MAT-253 Isotopic Mass Spectrometer with a fully automated interface for the pre-GC concen-tration (PreCon) of trace gases. The temporal and spatial variations of δ 15N and δ 18O in atmospheric N2O were analyzed. The mean δ 15N and δ 18O-N2O values above the oceanic surface were (7.21±0.50)‰ and (44.52±0.52)‰, respectively. From 30°N to Antarctica, the δ 15N (6.05‰―7.88‰) linearly increased with the rate of about 0.01‰ with the latitude while the δ 18O (43.05‰―48.78‰) showed a large fluctua-tion. The δ 15N negatively correlated with air temperature and N2O concentration, and slightly positively correlated with δ 18O. The summertime variations of δ 15N and δ 18O-N2O appeared the same trend on Millor Peninsula of eastern Antarctica. They significantly positively correlated with each other and negatively with N2O concentration. The δ 15N and δ 18O-N2O at different sites averaged (7.42±0.35)‰ and (44.69±0.49)‰, respectively, slightly higher than those above the oceanic surface, significantly higher than those of atmospheric N2O in the low-latitude regions of Northern Hemisphere. The predominant factors affecting the spatial variations of δ 15N and δ 18O values were also discussed. The isotopic data given in this study can help to investigate the global and regional N2O budgets.

关键词： nitrous oxide Antarctica atmosphere δ^(15)N δ^(18)O isotope ocean

Current Efficiency of Low Temperature Aluminum Electrolysis Studied by Neural Network

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 107-110页

作者： Huimin Lu Zuxian Qiu Keming Fang Fuming Wang Yanruo Hong( Metallurgy School, university of science and technology Beijing, Beijing 100083, china)( department of Nonferrous Metallurgy, Northeastern university, Shenyang 110006, china) Metallurgy School University of Science and Technology Beijing Beijing 100083 China department of Nonferrous Metallurgy Northeastern University Shenyang 110006 China

A prediction model for Current Efficiency (CE) of low temperature aluminum electrolysis (LTAE) with the low molar ratioelectfolyte of Na3AIF6-AIF3 - CaF2-MgF2-LiF -Al2O3 system was investigated based on artificial neural network principles. The nonlinearmapping between CE of LATE and various electrolytic conditions was obtained from a number of experimental data and used to predictCE of LATE. The trsined neural networks possessed high precision and resulted in a good predicting effect. As a result, attificial neuralnetworks as a new cooperating and predicting technology provide a new approach to the further studies on low temperature aluminumelectrolysis.

关键词： low temperatre aluminum electrolysis current efficiency neural network prediction model low molar ratio electrolyte

In-situ Preparation of Al/TiAl_3(P) Composite by Direct Reaction between Molten Al and TiO_2 Powder

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Journal of Materials science & technology 1998年第6期14卷 569-570页

作者： Yuyong CHEN Ziyong CHEN Qu SHU and Geying AN(National Defense precision Hot Processing Lab., Harbin Institute of technology Harbin 150006, china) National Defense precision Hot Processing Lab. Harbin Institute of Technology Harbin 150006 China

TiAl3 particle reinforced pure Al composite has been made by direct reaction among molten Al, TiO2 and a flux. The composite exhibits high Synthetically properties. The strength and hardness are higher than those of pure Al matrix by 71.5% and 134% respectively However, the elongation is 20.36%, slightly lower than that of the Al matrix.

关键词： TiO TiAl In-situ Preparation of Al/TiAl3 Composite by Direct Reaction between Molten Al and TiO2 Powder

An Application of Optimal Preview Control in Terrain Following System

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Journal of Systems Engineering and Electronics 2002年第1期13卷 21-26页

作者： Li Dongmei Dept. of precision Instrument and Mechanics, Tsinghua university, Beijing 100084, P.R.china Zhou Di, Hu Zhenkun & Hu Hengzhang Dept. of Control science and Engineering, Harbin Institute of technology, Harbin 150001, P.R.china Dept. of precision Instrument and Mechanics Tsinghua University Beijing 100084 P. R. China Dept. of Control science and Engineering Harbin Institute of Technology Harbin 150001 P. R. China

An optimal preview method is applied to the design of terrain following controller for cruise missile. In this method, tracking errors and control increments are both considered in the quadratic cost function. Integrating the general optimal servo system with a preview feedforward compensation that feeds forward future command and future disturbance produces an optimal preview servo system. In the terrain following system, the flight altitude of the cruise missile is a command signal, and its future information can be known apriori. Hence, we have designed a terrain following controller with a basic state feedback and a feedforward compensation for future altitude information. Simulation results show that the performance of the terrain following system with such an optimal preview controller has been improved dramatically.

关键词： Cruise missile Terrain following Preview control Optimal control Feedforward compensation.

Decision Cost Feature Weighting and Its Application in Intrusion Detection

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Wuhan university Journal of Natural sciences 2004年第5期9卷 765-769页

作者： QIANQuan GENGHuan-tong WANGXu-fa departmentofComputerscience.universityofSciene＆technologyofchina Hefei230027AnhuiChina

This paper introduces the cost-sensitive feature weighting strategy and its application in intrusion detection. Cost factors and cost matrix are proposed to demonstrate the misclassification cost for IDS. How to get the whole minimal risk, is mainly discussed in this paper in detail. From experiments, it shows that although decision cost based weight learning exists somewhat attack misclassification, it can achieve relatively low misclassification costs on the basis of keeping relatively high rate of recognition precision. Key words decision cost - feature weighting - intrusion detection CLC number TP 393. 08 Foundation item: Supported by the National Natural science Foundation Key Research Plan of china (90104030) and “20 Century Education Development Plan”Biography: QIAN Quan(1972-), male, Ph. D. research direction: computer network, network security and artificial intelligence

关键词： decision cost feature weighting intrusion detection