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A Cumulative Damage Reliability Model on the Basis of Contact Fatigue of the Rolling Bearing

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武汉理工大学学报 2006年第S1期28卷 367-370页

作者： HUANG Li (School of mechanical&Electrical engineering,wuhan {3. of technology,wuhan 43.070,china) School of mechanical&Electrical engineering Wuhan University of TechnologyWuhan 430070China

A cumulative damage reliability model of contact fatigue of the rolling bearing is more identical with the actual conditions. It is put forward on the basis of contact fatigue life probability distribution of the rolling bearing that obey Weibull distribution and rest on the Miner cumulative damage theory. Finally a case is given to predict the reliability of bearing roller by using these models.

关键词： rolling bearing reliability model cumulative damage contact fatigue

A new family of windows——convolution windows and their applications

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Science china(Technological Sciences) 2005年第4期48卷 468-480页

作者： ZHANG Jieqiu1,2, LIANG Changhong1 & CHEN Yanpu3.1. Department of Applied Math. & Phys., college of Science, Airforce engineering university, Xi’an 710051,{3. 2. National Key Laboratory of Antennas and Microwave technology, Xidian university, Xi’an 710071,{3. 3. Computer Center, Xi’an Communication college, Xi’an 710106,{3. Department of Applied Math. & Phys. College of Science Airforce Engineering University Xi’an China National Key Laboratory of Antennas and Microwave technology Xidian University Xi’an China Computer Center Xi’an Communication College Xi’an China

A new family of windows is constructed by convolutions via a few rectangular windows with same time width and is thus referred to as convolution windows. The expressions of the second-order up to the eighth-order convolution windows in both the time and frequency domains are derived. Their applications in high accuracy harmonic analysis of periodic signals are investigated. Comparisons between the proposed windows and some known windows with the same width shows that, when the synchronous deviation of data sampling is slight, the proposed ones have the least effect of spectral leakage. Therefore, the new windows are well suited for high accuracy harmonic analysis and parameter estimation for periodic signals. The error analysis and computer simulations show that the estimation errors, corresponding to frequency, amplitude and phase of every harmonic component of a signal, are proportional to the pth power of the relative frequency deviation in case of the pth-order convolution window is applied to windowing signal of approximately p cycles. By introducing real time adjustment in sampling interval, the proposed algorithm can adaptively trace signal frequency and lead to less sampling synchronous deviation. The proposed approach has the advantages of easy implementation and high measure precision and can be used in harmonic analysis of quasi-periodic signals whose fundamental frequency drifts slowly with time.

关键词： signal processing harmonic analysis window function convolution window synchronous error spoctral leakage

Description to wear debris boundaries by radar graph fractal method

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Chinese Science Bulletin 2007年第16期52卷 2285-2290页

作者： LIU HongTao1,2 & GE ShiRong1 1 Institute of Tribology and Reliability engineering,china university of Mining & {3.,Xuzhou 221008,china 2 college of mechanical and Electrical engineering,china university of Mining & {3.,Xuzhou 221116,china Institute of Tribology and Reliability engineering China University of Mining & Technology Xuzhou China college of mechanical and Electrical engineering China University of Mining & Technology Xuzhou China

In this paper,radar graph fractal method is introduced to describe wear debris boundaries. Research results show that it is a nice way to describe wear debris boundaries. Since the longest axis is selected as the first coordinate axis,its center point selected as the center point of the radar graph,and the co-ordinate value of wear debris boundary selected as the measure parameter,the limitations existing in Yard fractal measure method can be avoided. For any wear debris,its radar graph fractal dimension value is one and only,and as the wear debris shape changes from round to strip,the radar graph fractal dimension value also changes from low to high,showing strong uniqueness and independence. Due to the fact that the researched wear debris is gotten in different wear states,the results also prove that radar graph fractal dimension value is correlated with frictional pairs work condition and wear state. Radar graph fractal method is compared with Yard fractal measure methods,and results show that ra-dar graph fractal dimension values gotten from different wear debris have enough value grads to avoid effect of errors,and provide higher sensitivity for wear debris shape. This paper also discusses the influencing factors for radar graph fractal method. With the increase of the decomposing degree value,the radar graph fractal dimension tends to keep stable at one certain value,showing the typical characteristic of the fractal theory. All this proves that radar graph fractal method is an effective description method for wear debris boundaries.

关键词：磨粒边界雷达图表分形法

Tensile and compression properties of Zr-based bulk amorphous alloy at different temperatures

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Science china(Technological Sciences) 2005年第5期48卷 489-495页

作者： WANG Xu1,3. LOU Decheng1, GAO Zhanjun4, LIU Lei1, LIANG Hongmei1, WANG Qingfeng1, LI Qiang1,3.& MA Mingzhen1,2 1. Key Laboratory of Metastable Materials Science & technology of Hebei, Yanshan university, Qinhuangdao 066004, china 2. National Key Laboratory for Precision Hot Processing of Metals, Harbin Institute of technology, Harbin 150001, china 3. college of mechanical engineering, Yanshan university, Qinhuangdao 066004, china 4. Chinese Academy of engineering, Beijing 10003., china Key Laboratory of Metastable Materials Science & technology of Hebei Yanshan University Qinhuangdao China college of mechanical engineering Yanshan University Qinhuangdao China Chinese Academy of engineering Beijing China National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology Harbin China

mechanical properties of the Zr41Ti14Cu12.5Ni10Be22.5 bulk amorphous alloy at different temperatures were investigated. The compression test was carried out on a Gleebe-3.00 machine at 3.5 and 3.5°C, respectively, in the supercooled liquid region. It is shown that decreasing the compressive rate and increasing temperature have a similar influence trend on the compressive behavior of the bulk amorphous alloy. Room and low temperature tensile strengths were tested on the Instron materials testing system. At low temperature, the tensile strength decreased with decreasing of the testing temperature. Hardness measurement indicated that below the glass transition temperature, the hardness decreased with increasing of the annealing temperature and duration time. It, however, increased when the annealing treatment was performed above the glass transition temperature.

关键词： Zr41Ti14Cu12.5Ni10Be22.5 bulk amorphous alloy, mechanical properties, compressive deformation.

APPLICATION OF VECTOR ROTATING METHOD IN GRINDING INVOLUTE WORM WITH PLANE ENVELOPE METHOD

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Chinese Journal of mechanical engineering 1999年第4期12卷 317-320页

作者： Shang Xiangdong Fu Jingshun college of mechanical engineering,Shenyang Polytechnic {3. Duan Zhenyun Dalian {3. of technology 沈阳工业大学机械工程学院辽宁沈阳大连理工大学辽宁大连

The grinding principle of plane envelope is demonstrated with the medium rack *** basic and general fixing patterns of grinding involute worms with plane envelope method are *** vector rotating method is originally applied to calculate precisely the grinding wheel fixing angles γ h and γ n under the general fixing *** is proved with experiments that the method is feasible.

关键词： Medium rack Vector rotating Plane envelope Worm grinding

Design of the terminal of Split-type PCs

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Design of the terminal of Split-type PCs

A Multilevel Design Method of Large-scale Machine System Oriented Network Environment

E-Business·Creative Design·Manufacturing——2009 IEEE 10th International Conference on Computer-Aided Industrial Design & Conceptual Design（CAID&CD’2009）

作者： Chen Su School of mechanical engineering hubei university of technology {3. hubei Province 430068 china

As we enter the Information Age,as the main tool for information transmission Computers are playing so important roles in people’s lives that they have become irreplaceable *** most of the personal computer users are far from versed in computer *** is common phenomenon that they usually take personal computers as another kind of domestic ***,unavoidably lead to the monotony of personal computer *** makes it very difficult for personal computers to show and perform their full *** introduction of media center computers has in a certain extent facilitated people’s using experience of computers by enabling them to use personal computers in a much easier way at any *** as music video players,computer games,network applications *** there is long way to go before media center computers reach the point to bring in a breakthrough in the field of personal computer using and even to revolutionize personal computer using under the domestic *** this base,we put forward the concept of the design of split-type personal computer terminals under the domestic circumstance.

关键词： Split-type computer PC Interaction design Users’experience

来源： cnki会议评论

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cnki会议

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武汉理工大学学报 2006年第S2期28卷 565-569页

作者： LI Shuiping HE Jianjun (School of mechanical & Electronical engineering,wuhan {3. of technology,wuhan 43.070 ,china School of mechanical & Electronical engineering Wuhan University of TechnologyWuhan 430070China

The design of large-scale machine system is a very complex *** design problems usually have a lot of design variables and constraints so that they are difficult to be solved rapidly and efficiently by using conventional *** this paper,a new multilevel design method oriented network environment is proposed,which maps the design problem of large-scale machine system into a hypergraph with degree of linking strength (DLS) between *** decomposition of hypergraph,this method can divide the complex design problem into some small and simple subproblems that can be solved concurrently in a network.

关键词： design large-scale machine system degree of linking strength

Relationship between Multi-Phase Formation and Molecular Structure for Liquid Crystal System

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Journal of wuhan university of technology(Materials Science) 2005年第3期20卷 11-13页

作者：李振新 Biomedical Materials and engineering Centre Wuhan University of Technology Department of Life Science and technology Xinxiang Medicine CollegeXinxiang 453003 China

4 mechanical model of liquid crystals （ LCs ） was used to explain the phase formation and thermal properties . The LC plusses in the model are micro- machine systems consisting of an ensemble of molecular rotors, and some dynamie parameters in a semi-experiment molecular orbit method. A novel explanation on the multi-phase formation of LC system is obtained. It is found that the value of the critical rotational velueity is a key parameter for the characterization of each homologous series. The dipole moment of the molecules was also discussed.

关键词： liquid crystal phase dynamic molecular structure

Prediction and Control of both Wrinkle Limit and Fracture Limiton Cylindrical Cup Deep-drawing(Ⅱ)

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 201-204页

作者： Junxiang Lei Yonglin Kang(Department of mechanical engineering, Yantai university, Yantai 264005,{3.)(Material Science and engineering School, university of Science and technology Beijing, Beijing 100083.{3.) Department of mechanical engineering Yantai University Yantai 264005 China Material Science and engineering School University of Science and Technology Beijing Beijing 100083 China

The prediction and control criterion of both the wrinkle limit and fracture limit on the cylindrical cup deep-drawing are given, and the prediction and control diagram of both the wrinkle limit and fracture limit are also given. The results show that it is suitable for no-flange cylindrical cup deep-drawing, narrow-flange cylindrical cup deep-drawing, wide-flange cylindrical cup deep-drawing/expanding compound forming and rigid punch expanding forming.

关键词： cylindrical cup wrinkle limit fracture limit deep-drawing expanding forming compound forming