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31.
绿色供应链管理的基本原理   总被引:39,自引:0,他引:39  
人口、资源与环境三者之间的矛盾日益突显,要求制造业提高其活动与环境的相容性。绿色供应链管理是从系统的观点与集成的思想出发解决制造业与环境之间冲突的有效方式。从可持续发展的思想出发建立了绿色供应链的概念模型,分析了绿色供应链管理的目标,在此基础上探讨了绿色供应链管理的基本原理,认为共生原理、循环原理、替代转换原理与系统开放原理是实施绿色供应链管理应该遵循的基本原理。  相似文献   
32.
通过分析各种冲突解决方法的特点,提出了一种冲突的集成解决方案。采用面向对象的Object Pascal语言编制了一个实例,给出了该方法在零件结构工艺性设计中的具体应用。  相似文献   
33.
Intelligent multisensor surveillance systems consist of several types of sensors, which are installed on fixed and mobile devices. These components provide a huge quantity of information that has to be contrasted, correlated and integrated in order to recognize and react on special situations. These systems work in highly dynamic environments, with severe security and robustness requirements. All these characteristics imply the need for distributed solutions. In these solutions, scattered components can decide and act with some degree of autonomy (for instance, if they become isolated), or cooperate and coordinate for a complete tracking of special situations. In order to cope with these requirements and to better structure the solution, we have decided to design surveillance system control as a multiagent system. This is done by applying an agent-orientated methodology, which is assessed with concrete scenarios.  相似文献   
34.
In the last decade there was growing interest in strategic management literature about factors that influence a company's ability to use IT. There is general consensus that knowledge and competency are necessary in developing an IT capability, but there is very little understanding of what the necessary competencies are, and how they influence IS usage in different contexts. The small and medium-sized enterprise context is particularly interesting for two reasons: it constitutes a major part of the economy and it has been relatively unsuccessful in exploiting e-business.  相似文献   
35.
This paper introduces the Precise Rendering Method, which generates accurately anti-aliased and highlighted images from tessellated polygons. The Precise Rendering Method first solves the aliasing problems of hidden surface removal by using the Cross Scanline Algorithm. This algorithm can exactly calculate polygon areas projected onto each pixel by using horizontal and vertical scanlines. Aliasing artifacts in shading are then prevented by the Reflection Intergration Method, which analytically integrates the intensity of reflection in the solid angle defined by surface normals at vertices of the projected area. Several synthesized images are created to show the efficiency of the Precise Rendering Method.  相似文献   
36.
利用不可逆循环图代替传统的半不可逆循环推导出Clausius积分式,并用熵方程证明之,得出可逆过程膨胀功大于不可逆过程膨胀功。  相似文献   
37.
During the second part of the 1990s the Nordic (Denmark, Finland, Norway and Sweden) countries have created a unique multinational market for electricity. This paper aims to analyse the degree of integration of the different national markets that constitute the Nordic electricity market. In particular the Norwegian and Swedish wholesale and retail electricity markets are analysed. The results suggest that the wholesale markets are well integrated. Thus prices differ significantly only during periods with unusually high or low supply of hydropower. However, the retail markets are not integrated to the same degree. Thus retail prices and trade margins differ significantly. Differences in the national electricity market legislation seem to be a key factor behind these differences.  相似文献   
38.
虚拟企业中数字车间与供应链系统的集成与协调   总被引:1,自引:0,他引:1  
数字车间和供应链系统是虚拟企业的两个重要的功能组织。数字车间与供应链系统的信息集成和功能协调是虚拟企业能够高效运作的基础。Agent技术是构建大型、分布式系统的有效方法。本文研究了基于Agent技术的虚拟企业集成技术和协调机制。  相似文献   
39.
40.
This paper deals with the development of computational schemes for the dynamic analysis of flexible, nonlinear multi-body systems. The focus of the investigation is on the derivation of unconditionally stable time integration schemes for these types of problem. At first, schemes based on Galerkin and time discontinuous Galerkin approximations applied to the equations of motion written in the symmetric hyperbolic form are proposed. Though useful, these schemes require casting the equations of motion in the symmetric hyperbolic form, which is not always possible for multi-body applications. Next, unconditionally stable schemes are proposed that do not rely on the symmetric hyperbolic form. Both energy preserving and energy decaying schemes are derived that both provide unconditionally stable schemes for nonlinear multi-body systems. The formulation of beam and flexible joint elements, as well as of the kinematic constraints associated with universal and revolute joints. An automated time step selection procedure is also developed based on an energy related error measure that provides both local and global error levels. Several examples of simulation of realistic multi-body systems are presented which illustrate the efficiency and accuracy of the proposed schemes, and demonstrate the need for unconditional stability and high frequency numerical dissipation.  相似文献   
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