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INVESTIGATION ON DEPOSITIONS AND HARDNESS CHARACTERISTICS OF a-SiC:H FILMS

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 761-764页

作者： X.F.Rong and Z.Y.Qin college of mechanical engineering,Taiyuan university of technology, Taiyuan 030024, china Taiyuan Univ of technology Taiyuan China

In this paper, a deposition feature of a SiC:H films deposited by a RF sputtering system and a effect on the hardness of the films with various deposition conditions are investigated, and the effects of the silicon on a C:H are studied. It follows from the results that the properties of hardness can be changed with the depositing conditions. An increase of silane in the gas phase allows to deposit a SiC:H having tetrahedral structure. The sets of deposition conditions by which the different types of a SiC:H films can be deposited are obtained.

关键词： a SiC:H film sputtering hardness

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, china)(Material Science and engineering School, university of Science and technology Beijing, Beijing 100083, china) 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

Fractal Characteristic of Pits Distribution on 304 Stainless Steel Corroded Surface and Its Application in Corrosion Diagnosis

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Journal of Wuhan university of technology(Materials Science) 2007年第3期22卷 389-393页

作者：梁成浩 Electromechanics & Materials engineering college Dalian Maritime University

Electrochemical techniques and fractal theory were employed to study the corrosion behaviors and pits distribution characteristics on the corroded surfaces of 304 stainless steel exposed in FeCl3 solution. Fractal features of pits distribution over the corroded surfaces were observed and described by the fractal dimension. A 5-8-2 back-propagation （BP） artificial neural network model for the diagnoses of the pitting corrosion rate and pits deepness of 304 stainless steel under various conditions was developed by considering the fractal dimension as a key parameter for describing the pitting corrosion characteristics. The predicted results are well in agreement with the experimental data of pitting corrosion rate and pit deepness. The max relative errors between their experimental and simulation data are 6.69% and 4.62%, respectively.

关键词： 304 stainless steel pits distribution fractal neural network diagnosis

Further study of sources of the imported cobalt-blue pigment used on Jingdezhen porcelain from late 13 to early 15 centuries

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Science china(Technological Sciences) 2008年第3期51卷 249-259页

作者： DU Feng1 & SU BaoRu2 1 Institute of Chemistry & Molecular engineering, Qingdao university of Science & technology, Qingdao 266000, china 2.college of Information Science technology, Qingdao university of Science & technology, Qingdao 266000, china Institute of Chemistry & Molecular engineering Qingdao University of Science & Technology Qingdao 266000 China college of Information Science technology Qingdao University of Science & Technology Qingdao 266000 China

Based on the conclusion of modern scientific analysis: the cobalt-blue pigment applied on Jingdezhen official porcelain during Yuan Dynasty and prior to Xuande reign of Ming Dynasty (1271―1425) contains high iron and low manganese con- tents, and the cobalt during Xuande and after Xuande periods (after 1426) of Ming Dynasty contains high manganese and low iron contents, in combination with the traditional archaeological method, the related historical textual records were in- vestigated and analyzed, the imported cobalt employed on Jingdezhen official porcelain was studied comprehensively, systematically and logically. In fact, 'Su Ma Li Qing' (Samarra-blue) and 'Su Bo Ni Qing' (Sumatra-blue) are definitely different cobalt ores originated in different places, because of their very similar translitera- tions in Chinese, the confusion has appeared in ancient books for more than 400 years, which considered 'Su Ma Li Qing' and 'Su Bo Ni Qing' as the same co- balt-blue pigment. In this article the mistake was corrected, the possible producing places and the approximate eras of the two pigments imported to china and used at Jingdezhen were also suggested.

关键词： imported cobalt-blue pigments employed on official blue-and-white porcelain Yuan Dynasty early Ming Dy- nasty Mn/Fe content ratio Su Ma Li Qing (Samarra-blue) Su Bo Ni Qing (Sumatra-blue) scientific archae- ological research transliteration

Effects of MoS_2 on mechanical and tribological properties of NiCr-based alloys

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中国有色金属学会会刊：英文版 2000年第3期10卷 328-327,329-331页

作者： XIONG Dang sheng(熊党生) 1, PENG Chao qun(彭超群) 2, LIU Jin long(刘金龙) 1 1. college of mechanical engineering, china university of Mining and technology, Xuzhou 221008, P.R.china 2. State Key Lab for Powder Metallurgy, Central south Unive china Univ Min & Technol Coll Mech Engn Xuzhou 221008 Peoples R China Cent S Univ Technol State Key Lab Powder Met Changsha 410083 Peoples R China

Ni Cr based alloys with a wide temperature range self lubrication were made by hot pressing the mixture powder of alloyed Ni Cr powder, elemental Mo, Al, Ti and B powders and MoS 2 powder. The mechanical and tribological properties of these alloys when rubbing with Al 2O 3 ceramics and W18Cr4V high speed steel were measured in the temperature range of 20～700 ℃, and the mechanisms of self lubrication and wear resistance were studied. The results showed that the alloy containing 10% MoS 2 has the best combination of mechanical properties, antifriction and wear resistance. Over a wide temperature range from 20 ℃ to 700 ℃, when rubbing with Al 2O 3, its friction coefficient and wear rate are 0.19～0.3 and (1.1～1.5)10 -14 m 3/(N·m), respectively; when rubbing with the high speed steel, those values are 0.18 ～ 0.26 and (0.6～3.2)×10 -15 m 3/(N·m), respectively.

关键词： Ni Cr based alloys molybdenum disulfide self lubrication tribological properties

OPTIMIZATION DESIGN OF HYDRAULIC MANIFOLD BLOCKS BASED ON HUMAN-COMPUTER COOPERATIVE GENETIC ALGORITHM

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Chinese Journal of mechanical engineering 2003年第3期16卷 317-320页

作者： Feng YiLi LiTian ShujunSchool of mechanical engineering,Dalian university of technology,Dalian 116024, china School of mechanical engineering Dalian University of Technology Dalian 116024 China

Optimization design of hydraulic manifold blocks (HMB) is studied as acomplex solid spatial layout problem. Based on comprehensive research into structure features anddesign rules of HMB, an optimal mathematical model for this problem is presented. Usinghuman-computer cooperative genetic algorithm (GA) and its hybrid optitation strategies, integratedlayout and connection design schemes of HMB can be automatically optimized. An example is given totestify it.

关键词： Hydraulic manifold blocks (HMB) Human-computer cooperation Geneticalgorithm Optimization design

STUDY ON INJECTION AND IGNITION CONTROL OF GASOLINE ENGINE BASED ON BP NEURAL NETWORK

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Chinese Journal of mechanical engineering 2003年第4期16卷 441-444页

作者： Zhang Cuiping Yang Qingfocollege of mechanical engineering,Taiyuan university of technology,Taiyuan 030024, china college of mechanical engineering Taiyuan University of Technology Taiyuan 030024 China

According to advantages of neural network and characteristics of operatingprocedures of engine, a new strategy is represented on the control of fuel injection and ignitiontiming of gasoline engine based on improved BP network algorithm. The optimum ignition advance angleand fuel injection pulse band of engine under different speed and load are tested for the samplestraining network, focusing on the study of the design method and procedure of BP neural network inengine injection and ignition control. The results show that artificial neural network technique canmeet the requirement of engine injection and ignition control. The method is feasible for improvingpower performance, economy and emission performances of gasoline engine.

关键词： Neural network BP algorithm Gasoline engine Control

LEVEL SET METHOD FOR TOPOLOGICAL OPTIMIZATION APPLYING TO STRUCTURE, MECHANISM AND MATERIAL DESIGNS

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Chinese Journal of mechanical engineering 2004年第2期17卷 200-209页

作者： Mei Yulin Wang Xiaoming Department of mechanical engineering,Dalian university of technology,Dalian 116024,china Department of mechanical engineering Dalian University of Technology Dalian 116024 China

Based on a level set model, a topology optimization method has been suggestedrecently. It uses a level set to express the moving structural boundary, which can flexibly handlecomplex topological changes. By combining vector level set models with gradient projectiontechnology, the level set method for topological optimization is extended to a topologicaloptimization problem with multi-constraints, multi-materials and multi-load cases. Meanwhile, anappropriate nonlinear speed, mapping is established in the tangential space of the activeconstraints for a fast convergence. Then the method is applied to structure designs, mechanism andmaterial designs by a number of benchmark examples. Finally, in order to further improvecomputational efficiency and overcome the difficulty that the level set method cannot generate newmaterial interfaces during the optimization process, the topological derivative analysis isincorporated into the level set method for topological optimization, and a topological derivativeand level set algorithm for topological optimization is proposed.

关键词： Level set method Topology optimization Mean curvature flow Materialdesign Mechanism design Topological derivative

NOVEL FORMULATION OF STATIC STABILITY FOR A WALKING QUADRUPED ROBOT

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Chinese Journal of mechanical engineering 2003年第2期16卷 120-122页

作者： Chen XuedongSchool of mechanical Scienceand engineering,Huazhong university of Scienceand technology,Wuhan 430074, china School of mechanical Science and engineering Huazhong University of Science and Technology Wuhan 430074 China

By defining the static stable area for foot placement, a new approach toanalysis of quadruped robot stability is presented. Unlike conventionally, the method avoids solvingcomplicated direct kinematics of quadruped robot and shows the information on the robot stabilityand the selection of swing leg. Especially, the proposed algorithm can be used as real-timeoperation for on-line gait generation and control for quadruped robots. The effectiveness of theproposed approach is shown through a practical crawling experiment of the quadruped robotTITAN-VIII.

关键词： quadruped robot static stability gait generation