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The CAD/CAM Solution and Realization for Machining Large Scale Steel-concrete Objects

厦门大学学报（自然科学版） 2002年第S1期41卷 14-15页

作者： ZHENG Yong-qian, CHEN Bing-sen, ZHANG Wei-min, FAN Liu-qun (department of Mechanical engineering, tongji university, {3., China)

First the architecture of the integrated CAD/CAM system developed for machining large scale steel-concrete girders using I-DEAS and other developing tools are introduced; then the involved technologies in the development of the system are presented, which include the method for determining the position and orientation of the manufacturing features, the method for geometrical modeling of the girders, the techniques for generating the toolpaths for the 5-axis machining centers, the generative process planning technique and the postprocssing technique for the specific machines etc. Moreover some related special technical issues are also discussed. The CAD/CAM system is a network-based workshop-oriented manufacturing system, in which every machining cell can work independently serving two machining lines. The cell server take charge of the management of work schedules, personnel, machining resources, databases etc. the control computer serves to monitor the whole manufacturing lines, to arrange tasks, and to communicate; the two CAD/CAM workstations’ work is to model the girders using the CAD data, to plan the process and to generate the NC programs. The CL files that describe the toolpaths generated are ATP-format files. In order to translate them into NC codes that can be directly used by the 5-axis machining centers, a specific postprocessing program is developed for these distinct machines. The system has been successfully realized and applied in shanghai Maglev Transrapid project. In the developing process, the following technical problems are solved: 1. Algorithms for measuring, positioning, and machining complex objects. 2. Methods for Modeling. 3. Animation and postprocess techniques for 5-axis machining centers. 4. Technologies for machining large-scale concrete-steel structures Although further evolution is needed for this system, the facts have proven its performance satisfactory and the technologies and the methods developed suitable.

关键词： maglev transrapid CAD/CAM manufacturing feature Pseudo-NC Real-NC post process

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A MULTI-GRID ALGORITHM FOR STOKES PROBLEM

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Journal of Computational Mathematics 1995年第4期13卷 291-305页

作者： Z. Huang(department of Applied Mathematics, tongji university, shanghai, China) tongji UNIV DEPT MATH APPLSHANGHAI 200092PEOPLES R CHINA

In this paper we describe a multi-grid algorithm for the penalty procedure of Stokes problem. It is proved that the convergence rate df the algorithm is bounded away from 1 independently of the meshsize. For convenien... 详细信息

关键词： Math Grid ED EH Bank

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Effect of transforming growth factor-beta on activity of connective tissue growth factor gene promoter in mouse NIH/3.3.fibroblasts

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Acta Pharmacologica Sinica 2004年第4期25卷 87-91页

作者： Qing ZHAO, Nan CHEN2, Wei-ming WANG, Jian LU3.Bing-bing DAI3. department of Nephrology, Ruijin Hospital 3.0} of Biochemistry, shanghai Second Medical {3., shanghai 200025, China department of Nephrology Ruijin Hospital

AIM: To investigate the regulatory mechanism of transforming growth factor-betaon activity of connective tissue growth factor promoter in mouse NIH/3.3.fibroblasts. METHODS: The regulation fragment of the 5' flanking region of the human CTGF gene was linked to pGL3.Basic vector, a firefly luciferase reporter construct without promoter. The recombinant plasmid pCTGF-luc was transiently transfected to NIH/3.3.fibroblasts. The activity of CTGF promoter after treatment of TGF-β1 and MAPK pathway inhibitors were assayed with luciferase reporter gene assay system. RESULTS: TGF-β1-induced increase of CTGF promoter activity was concentration-dependent, with a plateau at 5 μg/L by 2.67-fold vs control (P2 h and maintained to 24 h by 2.76- and 2.20-fold vs control, respectively (P203.80 (10 μmol/L), the p3. MAP kinaseinhibitor, decreased basal and TGF-β1-induced activation of CTGF promoter. However, inhibition of c-Jun-N-terminal kinase/stress-activated protein kinase by SP600125 (20 μmol/L) was without effect. CONCLUSION: TGF-β1stimulated the transcriptional activity of CTGF gene promoter in NIH/3.3.fibroblasts in a dose- and time-dependent manner. MAPK pathway may play a role in the regulation of TGF-β1-induced CTGF expression.

关键词： transforming growth factor-beta connective tissue growth factor promoter mitogen-activated protein kinases signal transduction

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Noether-type theory for discrete mechanico-electrical dynamical systems with nonregular lattices

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Science China(Physics,Mechanics & Astronomy) 2010年第9期53卷 1687-1698页

作者： FU JingLi1,CHEN LiQun2 & CHEN BenYong3.1 Institute of Mathematical Physics,Zhejiang Sci-Tech university,Hangzhou 3.0018,China 2 department of Mechanics,shanghai university,shanghai 200072,China 3.Faculty of Mechanical-engineering & Automation,Zhejiang Sci-Tech university,Hangzhou 3.0018,China 1. Institute of Mathematical Physics Zhejiang Sci-Tech University Hangzhou 310018 China2. Department of Mechanics Shanghai University Shanghai 200072 China3. Faculty of Mechanical-Engineering & Automation Zhejiang Sci-Tech University Hangzhou 310018 China

We investigate Noether symmetries and conservation laws of the discrete mechanico-electrical systems with nonregular *** operators of discrete transformation and discrete differentiation to the right and left are introduced for the *** on the invariance of discrete Hamilton action on nonregular lattices of the systems with the dissipation forces under the infinitesimal transformations with respect to the time,generalized coordinates and generalized charge quantities,we work out the discrete analog of the generalized variational *** this formula we derive the discrete analog of generalized Noether-type identity,and then we present the generalized quasi-extremal equations and properties of these equations for the *** also obtain the discrete analog of Noether-type conserved laws and the discrete analog of generalized Noether theorems for the *** we use an example to illustrate these results.

关键词： Noether symmetry variational formula quasi-extremal equation conservation law discrete mechanico-electrical dynamical system

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Impact chaos control and stress release——A key for development of ultra fine vibration milling

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Progress in Natural Science:Materials International 2002年第5期12卷 18-23页

作者： WANG Shulin(department of Power engineering, university of {3. for Science and Technology, {3. 200093. China) shanghai Univ Sci & Technol Dept Power Engn Shanghai 200093 Peoples R China

Through our previous experimental and analytical studies, it has been discovered that the key for the development of vibration milling is the impact chaos control and stress release. The necessities for the chaos control and stress release are: (i) to strictly e-liminate the sub-harmonics; (ii) to control the super-harmonics to a lower level and (iii) to load the system compressively with relatively higher period, in order that the vibration energy can be absorbed by the particles effectively and sufficiently. A new vibration model for ultra fine milling is proposed, which has wide applications in preparing ultra fine particles.

关键词： vibration mills ultra fine milling impact chaos control stress release.

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Global existence of smooth solutions to two-dimensional compressible isentropic Euler equations for Chaplygin gases

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Science China Mathematics 2010年第3期53卷 719-738页

作者： KONG DeXing 1 , LIU KeFeng 2 & WANG YuZhu 3. 1 department of Mathematics, Zhejiang university, Hangzhou 3.0027, China 2 department of Mathematics, university of California at Los Angeles, CA 90095, USA 3.department of Mathematics, shanghai Jiao Tong university, shanghai 200248, China 1. department of Mathematics Zhejiang University Hangzhou 310027 China2. Department of Mathematics University of California at Los Angeles Los Angeles CA 90095 USA3. Department of Mathematics Shanghai Jiao Tong University Shanghai 200248 China

In this paper we investigate the two-dimensional compressible isentropic Euler equations for Chaplygin gases. Under the assumption that the initial data is close to a constant state and the vorticity of the initial velocity vanishes, we prove the global existence of the smooth solution to the Cauchy problem for twodimensional flow of Chaplygin gases.

关键词： Chaplygin gases compressible Euler equations irrotational flow null condition Cauchy problem smooth solution

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确定岩土边坡潜在破裂面的组合优化法

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同济大学学报（自然科学版） 2004年第5期32卷 561-564页

作者：冯紫良冯时恩同济大学地下建筑与工程系上海200092

提出了一种可用于复杂应力状态下土坡稳定分析的新方法 .该法利用可靠度理论建立判断土体破裂线的准则 ,将有限元网格中的单元和节点作为组合优化的对象 ,结合Dijkstra最短路径算法确定土坡中最危险的潜在破裂面 .较详细地叙述了这种基... 详细信息

提出了一种可用于复杂应力状态下土坡稳定分析的新方法 .该法利用可靠度理论建立判断土体破裂线的准则 ,将有限元网格中的单元和节点作为组合优化的对象 ,结合Dijkstra最短路径算法确定土坡中最危险的潜在破裂面 .较详细地叙述了这种基于有限元分析技术和组合优化法来确定土坡中最危险的潜在破裂面的原理和实施过程 ,并给出了计算实例 .最后对这种方法作出了讨论 .

关键词：边坡稳定破裂面优化最短路径有限元

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SCHWARZ-PICK ESTIMATES FOR BOUNDED HOLOMORPHIC FUNCTIONS ON CLASSICAL DOMAINS

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Acta Mathematica Scientia 2011年第4期31卷 1377-1382页

作者：刘洋陈志华 department of Mathematics Zhejiang Normal University department of Mathematics Tongji University

In this paper, Schwarz-Pick estimates for high order Fr′echet derivatives of bounded holomorphic functions on three kinds of classical domains are presented. We generalize the early work on Schwarz-Pick estimates of ... 详细信息

关键词： Schwarz-Pick estimate holomorphic functions classical domains

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MAGNETIC　INVESTIGATION　OF　THE　NICKEL　COMPLEXES　OF　MULTI－SULFUR　1．2－DITHIOLATES

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Chinese Chemical Letters 1996年第7期7卷 685-686页

作者： Tian Ming YAO Xian Fa SHI Xiao Zeng YOU(department of Chemistry,tongji university, shanghai 200092)(State Key Laboratory of Coordination Chemistry,Nanjing {3.,Nanjing 210093. tongji UNIV DEPT CHEMSHANGHAI 200092PEOPLES R CHINA NANJING UNIV STATE KEY LAB COORDINAT CHEMNANJING 210093PEOPLES R CHINA

The magnetic susceptibility of (Bu4N)(NI(MEDT)2) and (Bu4N)(Ni(PHDT)2)(MEDT:5-methyl-6-hydro-1, 4-dithiin-2, 3.dithiolate, PHDT: 5-phenyl-6-hydro-1.4-dithiin- 2,3.dithiolate) was measured in the temperature range of 75-3.0K. The magnitudeof magnctic moments is consistent,with a doublet state arising from Ni(Ⅲ).Antiferromagnetic properties were discussed in consideration of molecularstructure.

关键词： MULTI DITHIOLATES INVESTIGATION MAGNETIC COMPLEXES NICKEL OF SULFUR THE

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A complex variable meshless method for fracture problems

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Science China(Physics,Mechanics & Astronomy) 2006年第1期49卷 46-59页

作者： CHENG Yumin1 & LI Jiuhong2 1. shanghai Institute of Applied Mathematics and Mechanics, shanghai university, shanghai 200072, China 2. department of Building engineering, Xi’an university of Technology, Xi’an 710048, China shanghai Institute of Applied Mathematics Mechanics Shanghai University Shanghai 200072 China department of Building engineering Xi’an University of Technology Xi’an 710048 China

Based on the moving least-square (MLS) approximation, the complex variable moving least-square approximation (CVMLS) is discussed in this paper. The complex variable moving least-square approximation cannot form ill-conditioned equations, and has greater precision and computational efficiency. Using the analytical solution near the tip of a crack, the trial functions in the complex variable moving least-square approxi- mation are extended, and the corresponding approximation function is obtained. And from the minimum potential energy principle, a complex variable meshless method for fracture problems is presented, and the formulae of the complex variable meshless method are obtained. The complex variable meshless method in this paper has greater precision and computational efficiency than the conventional meshless method. Some examples are given.

关键词： moving least-square approximation, complex variable moving least-square approximation, meshless method, complex variable meshless method, fracture.

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