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PULSED nd-YAG LASER WELDInG OF An AI-SiC_p MEtAL MAtRIX COMPOSItE

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Chinese Journal of Aeronautics 1997年第1期10卷 75-80页

作者： Xu Jiukua Jiang Chengyu(mechanical engineering Institute, nanjing university of Aeronauticsand Astronautics, nanjing, 210016, China)Yu Damin Liu Weicheng(department of manufacturing engineering, Hong Kong Polytechnic university) mechanical engineering Institute Nanjing Univ. Aero. and Astronaut. Nanjing 210016 China Dept. of manufacturing engineering Hong Kong Polytechnic University Hong Kong

A study is presented of the laser welding behaviour of an SiC particulate re-inforced Al-alloy comPOsite using a pulsed nd-YAG laser. the influences of laser weldingparameters of laser intensity, pulse duration and the beamjs focus position on the depth ofweld penetration as well as the size of weld bead width were investigated. A typical mi-crostructure of a weld section reveals that the three distinct zones are present. Cracks andporosity were fOund to be two major defects in laser welded metal matrix composites(MMC). these investigations have led to an optimum welding condition proposed forlaser welding of SiC partiulate reinforced aluminium alloy comPosites with minimum de-fects.

关键词： metal matrix composites laser welding laser intensity peak power

Effect of Cooling Rate on Morphology and Oxygen Permeability of Polypropylene

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 219-223页

作者： Wei tian Raymond t. Whodhams(Material Science and engineering School, university of Science and technology Beijing, Beijing 100083, China)(department of Chemical engineering and Applied Chemistry university of toronto, toronto M5S IA4, canada) Material Science and engineering School University of Science and Technology Beijing Beijing 100083 China department of Chemical engineering and Applied Chemistry University of Toronto Toronto Ont. M5S IA4 Canada

the influence of different cooling rates on the morphology and oxygen permeabilityr of polypropylene containing ferrocene has been investigated. the spherulitic crystalline size and structure, which can affect the oxygen permeability are dependent upon the heating temperature, annealing time and cooling rate. the modulus of the composite was measured b}' dynamic mechanical analysis.

关键词： polypropylene oxygen permeability cooling rate

Studying on the Fuzzy-QFD System Based on Database Class Encapsulation technology

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武汉理工大学学报 2006年第S1期28卷 388-392页

作者： FAnG Xifeng1,ZHAnG Shengwen1,LU Yuping2,WU Hongtao2 (1. mechanical and Power engineering Institute,Jiangsu university of Science and technology,Zhenjiang 212003,China 2. College of Automation engineering,nanjing university of Aeronautics and Astronautics,nanjing 210016,China) mechanical and Power engineering Institute Jiangsu University of Science and technologyZhenjiang 212003China College of Automation engineering Nanjing University of Aeronauticsand AstronauticsNanjing 210016China

Complicated product QFD system design information including design and manufacturing, operation and maintenance as well as relative supply information, all are tightly related to the product life cycle cooperative design and the process of establishing the QFD system. In the early stage of product design, we can only get the fuzzy and unreliable information. With design going, the fuzzy and unreliable information become less and less. the defect of the traditional QFD is not deal with the fuzzy contents very well. Adopt database class encapsulation and fuzzy inference technology, and then discuss the realization of QFD system based on VFP database. the structure of the fuzzy QFD system based on database class's encapsulation is built and the work flow of fuzzy algorithm based on VFP software is presented. In the analysis of fuzzy QFD process, fuzzy inference is adopted. A developed prototype system and an example have verified some presented techniques and the research results are the basis of the future development.

关键词： quality function deployment(QFD) database class encapsulation fuzzy inference

test and Experiment Study on Synchronous Cooperative Design System Over networked manufacturing Platform

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武汉理工大学学报 2006年第S2期28卷 656-658页

作者： LUO Yabo~1 ZHEnG Li~2 ZOU Shiwei~1 ZHAO Liang~1 1.School of mechanical and Electrical engineering,Wuhan university of technology,Wuhan 430070,China 2.department of Biology and Light Industry,Changsha university of Science and technology,Changsha 410076,China School of mechanical and Electrical engineering Wuhan University of TechnologyWuhan 430070China department of Biology and Light Industry Changsha University of Science and TechnologyChangsha 410076China

Based on the analysis on the previous research in virtual manufacturing and virtual enterprises,this paper pro- vides a novel architecture of networked manufacturing system around the cooperative *** key technologies for synchronous cooperative design in networked manufacturing platform,such as the cooperative mechanism,cooperative rules,control authority conveyed,cooperative efficiency,are detailed,with which a synchronous cooperative design system is *** to the cooper- ative efficiency is the major bottleneck of the synchronous cooperative design over Internet,this research details the test and experi- ment to demonstrate the practicality of the *** the advantages of the system are illustrated compared with current soft- ware tools.

关键词： networked manufacturing synchronous cooperative design resource sharing

Development and characterization of 3D-printed electroconductive pHEMA-co-MAA nP-laden hydrogels for tissue engineering

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Bio-Design and manufacturing 2024年第3期7卷 262-276页

作者： Sara De nitto Aleksandra Serafin Alexandra Karadimou Achim Schmalenberger John J.EMulvihill Maurice n.Collins DIBRIS Polytechnic Inter-School Section University of Genoa16126 GenoaItaly School of engineering Bernal InstituteUniversity of LimerickLimerick V94 T9PXIreland School of natural Sciences Department of Biological SciencesUniversity of LimerickLimerick V94 T9PXIreland Health Research Institute University of LimerickLimerick V94 T9PXIreland AMBER University of LimerickLimerick V94 T9PXIreland

tissue engineering(tE)continues to be widely explored as a potential solution to meet critical clinical needs for diseased tissue replacement and tissue *** this study,we developed a poly(2-hydroxyethyl methacrylate-co-methacrylic acid)(pHEMA-co-MAA)based hydrogel loaded with newly synthesized conductive poly(3,4-ethylene-dioxythiophene)(PEDOt)and polypyrrole(PPy)nanoparticles(nPs),and subsequently processed these hydrogels into tissue engineered constructs via three-dimensional(3D)*** presence of the nPs was critical as they altered the rheological properties during ***,all samples exhibited suitable shear thinning properties,allowing for the development of an optimized processing window for 3D *** were 3D printed into pre-determined disk-shaped configurations of 2 and 10 mm in height and diameter,*** observed that the nPs disrupted the gel crosslinking efficiencies,leading to shorter degradation times and compressive mechanical properties ranging between 450 and 550 *** conductivity of the printed hydrogels increased along with the nP concentration to(5.10±0.37)×10^(−7)S/*** vitro studies with cortical astrocyte cell cultures demonstrated that exposure to the pHEMA-co-MAA nP hydrogels yielded high cellular viability and proliferation ***,hydrogel antimicrobial studies with staphylococcus epidermidis bacteria revealed that the developed hydrogels affected bacterial *** together,these materials show promise for various tE strategies.

关键词： Conductive nanoparticles Hydroxyethyl methacrylate(HEMA) Ultraviolet(UV)polymerization 3D printing

基于GSPn方法的柔性制造系统过程模型和性能分析(英文)

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系统仿真学报 2008年第19期20卷 5258-5261页

作者：马增治王龙山高洪吉林大学机械科学与工程学院长春130025 长春大学机械工程学院长春130022

应用广义随机Petri网方法,对柔性制造系统进行建模和分析,提出了控制策略和优化方法。针对柔性制造系统的离散性,对整个系统的过程模型进行分析。利用广义随机 Petri 网结合马尔可夫链的方法,确立了系统的配置参数,得出了系统的平均运... 详细信息

应用广义随机Petri网方法,对柔性制造系统进行建模和分析,提出了控制策略和优化方法。针对柔性制造系统的离散性,对整个系统的过程模型进行分析。利用广义随机 Petri 网结合马尔可夫链的方法,确立了系统的配置参数,得出了系统的平均运行时间,机床的平均使用率,系统的生产率,故障概率,对系统的优化和生产效率的提高以及柔性的提高提供了理论支持。最后,通过柔性制造系统实例,对该方法进行了检验。

关键词：广义随机Petri 网(GSPn) 柔性制造系统马尔可夫链过程模型

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电脉冲消除45钢淬火件的残余应力

浙江大学学报（工学版） 2012年第8期46卷 1407-1411页

作者：郑建毅何闻施彦彬浙江大学流体传动及控制国家重点实验室浙江省先进制造技术重点实验室现代制造工程研究所浙江杭州310027 厦门大学机电工程系福建厦门361005

为了研究电脉冲消除金属材料内部残余应力的效果,通过储能电容器放电产生高能电脉冲,对淬火后的45优质碳素结构钢冷轧薄板件进行放电处理,采用小孔法测定电脉冲处理前后试样内残余应力的变化规律.用于电脉冲处理的脉冲电流为指数衰减的... 详细信息

为了研究电脉冲消除金属材料内部残余应力的效果,通过储能电容器放电产生高能电脉冲,对淬火后的45优质碳素结构钢冷轧薄板件进行放电处理,采用小孔法测定电脉冲处理前后试样内残余应力的变化规律.用于电脉冲处理的脉冲电流为指数衰减的振荡波形,同时满足第一个主峰的电流密度为12.2kA/mm2,单次处理的振荡脉冲持续时间小于0.8ms.试验结果表明,经过电脉冲处理后,45钢淬火件中2个主方向残余应力的幅值均出现较为显著的降低,且两者都出现均化效果.

关键词：电脉冲 45钢残余应力小孔法

Digital Manufacture techniques for Large Hydro turbine's Blades

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武汉理工大学学报 2006年第S2期28卷 700-704页

作者： LAI Xide~1 ZHAnG Qinghua~1 ZHOU Yunfei~2 YAn Sijie~2 1.School of Energy & Environment,Xihua university,Chengdu 610039,China 2.School of mechanical Science,Huazhong university of Science and technology,Wuhan 430074 ,China School of Energy & Environment Xihua UniversityChengdu 610039China School of mechanical Science Huazhong University of Science and TechnologyWuhan 430074China

Blades are one of the vital components and most difficulty in manufacturing of large hydro *** order to cost-effectively and productively manufacture these kinds of blades,a series of digital techniques in manufacturing have been devel- oped,which includes digital design of hydro turbine blades based on manufacture’ requirements,Computer-aided location and the machined error evaluation by using 3-dimensional digitized measuring,tool path generation strategy to meet requirements of en- hancing machining efficiency and controlling deviation in nC machining,tool path generation and nC machining simulation by es- tablishing a virtual nC machining environment for blades,and reasonable and feasible strategy and the systematic scheme for man- ufacturing of large blades by using 5-axis simultaneous CnC *** developed digital manufacture techniques have been successfully applied in manufacturing of both the large Kaplan and Francis hydraulic turbine blades;it shows that higher efficiency and the better surfaces finish accuracy can be achieved.

关键词： digital manufacture hydraulic turbine blade nC Machining CAD/CAM

FLOW PAttERnS AnD FORCE CHARACtERIStICS OF LAMInAR FLOW PASt FOUR CYLInDERS In DIAMOnD ARRAnGEMEnt

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Journal of Hydrodynamics 2011年第1期23卷 55-64页

作者： ZOU Lin LIn Yu-feng LU Hong School of mechanical and Electronic engineering Wuhan University of Technology Wuhan 430070 China department of mechanical engineering The Hong Kong Polytechnic University Hong Kong China

A three-dimensional numerical investigation of cross-flow past four circular cylinders in a diamond arrangement at Reynolds number of 200 is carried *** the spacing ratios（L /D）ranging from 1.2 to 5.0,the flow patterns can be classified into three basic *** critical spacing ratio for the transition from narrow gap flow pattern to vortex impingement flow pattern around the cylinders is found to beL /D=3.0,while a single bluff-body flow pattern is observed atL /D=*** relationship between the three-dimensional flow patterns and force characteristics around the four cylinders shows that the variation of forces and Strouhal numbers againstL /D are generally governed by these three kinds of flow *** is concluded that the spacing ratio has important effects on the development of the free shear layers about the cylinders and hence has significant effects on the force and pressure characteristics of the four cylinders with different spacing ratios.

关键词： four cylinders spacing ratio flow pattern force characteristics