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关键词： 离散结构   自组织   阴阳平衡   内经   有序  

摘要： 运用离散结构理论和自组织理论中“系统开放”原理、“非线性相互作用”原理和“涨落突变”原理 ,结合《内经》中的阴阳非平衡观点 ,分析了《内经》中的“阴阳平衡” ,认为《内经》所说的阴阳平衡是动态平衡 ,人的生命过程是一种非平衡的有序。因此《内经》的阴阳平衡与离散结构理论关于“非平衡是有序之源”

关键词： 有限元   接触热阻   离散结构   三维瞬态温度场  

摘要： 阐述了离散结构温度场分析的基本理论，介绍了用于离散结构温度场分析的ＡＳＴＳＡ软件系统，并引用算例对如何使用该软件进行离散结构温度场分析进行了说明。

关键词： structural optimisation   finite element analysis   evolutionary method   size optimisation   topology optimisation   3D rigid frames  

摘要： The single most researched and analysed topic in the held of structural optimisation in the last 40 years has been that of size optimisation for pin- and rigid-jointed frames. Much of the effort has been in developing the search engines that will find a global weight/volume minimum in the presence of multiple constraints, not all of which may be active at the minimum. Most of the algorithmic developments have followed formal mathematical programming techniques. Recently more heuristic methods have emerged for structural optimisation such as genetic algorithms, simulated biological growth and evolutionary algorithms. The authors have been researching the latter mentioned evolutionary structural optimisation (ESO) method for the last six years and have found it to be most efficacious for the full range of structural situations;topology, shape and size optimisation with stress, stiffness, frequency, stability constraints in 2D and 3D with single or multiple loads and support conditions. In the present work is a summary of some of our ESO research for pin and rigid-jointed 2D and 3D frames with or without multiple loads. The paper presents the simple evolutionary algorithm and gives examples covering the range of applications. Attention is also given to benchmarking the algorithms and to their reliability and robustness. (C) 2000 Elsevier Science S.A. All rights reserved.

关键词： 涂层方法   气相沉积   气相淀积   离散结构   等离子  

摘要： 公开号　ＣＮ1256324Ａ　　申请人　西北工业大学　　地址　710072陕西省西安市友谊西路127号　　本发明涉及一种在高速钢、硬质合金、陶瓷制金属切削工具上获得耐磨涂层的工艺方法,其特征在于;被强化零件的表面涂层采用一种厚薄不均匀的离散涂层结构,得到离散涂层结构的方法可以用网状遮屏安装在被强化零件表面和蒸发材料之间,网状遮屏可以由需向涂层添加的某种或某几种组元的材料制成,它同时起着遮屏和阴极的作用。本发明相比现有技术的优点在于:由于采用了涂层某些或某种组元制成的网状遮屏,从而可应用比较简单的设备和工艺,制备多元多层离散涂层。同时还增加了工艺的可控制性,加宽工艺可调范围。本发明方法适用于高速钢,硬质合金和陶瓷制金属切削工具的表面强化。真空等离子气相沉积多元多层离散结构涂层方法

关键词： structural optimization   structural analysis   weight   stress analysis  

摘要： Deals with an approximate, but very simple, method of finding the minimum of structural weight under static loads. The design consists of assigning an appropriate rolled profile, from a given catalogue, to each structural member. The design is then formulated as a discrete structural optimization problem. The structure may be subjected to an arbitrary number of constraints imposed on stresses and structural material from members with the least stress. Presented examples are showing that the Problems with k(o) catalogue elements, and j(o) structural members, including k(o) to the power j(o) combinations, can be solved with k(o)j(o) analyses only. The knowledge needed to solve the Problem is limited to structural analysis.

关键词： 遗传算法   优化设计   空间桁架   离散结构  

摘要： 离散结构的形状优化问题，设计变量是不同性态的连续／离散混合变量，优化收敛困难。本文利用遗传算法实现其全局最优设计，以空间２５杆桁架结构为例，进行了多变量、多工况的结构形状遗传优化设计。为减少结构重分析次数，引入了Ｓｔｅａｄｙｓｔａｔｅ算法。结果表明结构形状的遗传优化设计方法是可行的。

关键词： discrete element   Principle-Based Ethics   industries   aluminium   isomers  

摘要： We show how the strategy used in the well-known DENDRAL system (Lindsay et al., 1980) fits into a general scheme and refine the strategy by applying the same principles again. We report on an implementation, MOLGEN (Grund et al., 1992) which has been tested on real life problems in industry.

关键词： 最优设计   弹塑性   灵敏度   离散结构  

摘要： 通过桁架实例说明了非线性结构响应对断面积的灵敏度，在材料刚度发生变化的点是不连续的；用传统的增量法不能准确地计算非线性响应灵敏度，用全局差分法计算非线性灵敏度也有特殊的困难。在分析其原因的基础上给出了非线性结构响应灵敏度值在间断点处跳跃值的算法公式，提出了增量法的修正公式。三杆桁架的例子被用来证明这些结论的正确性。

关键词： Comparative Analysis   Cost Effectiveness   Economic Research   Organizational Theories   Statistical AnalysisContract Law   Institutional Economics   Structural Analysis (Economics)  

摘要： This paper combines institutional economics with aspects of contract law and organization theory to identify and explicate the key differences that distinguish three generic forms of economic organization--market, hybrid, and hierarchy. The analysis shows that the three generic forms are distinguished by different coordinating and control mechanisms and by different abilities to adapt to disturbances. Also, each generic form is supported and defined by a distinctive type of contract law. The cost-effective choice of organization form is shown to vary systematically with the attributes of transactions. The paper unifies two hitherto disjunct areas of institutional economics--the institutional environment and the institutions of governance--by treating the institutional environment as a locus of parameters, changes in which parameters bring about shifts in the comparative costs of governance. Changes in property rights, contract law, reputation effects, and uncertainty are investigated. [ABSTRACT FROM AUTHOR]

关键词： 智能化   信息系统   离散结构