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121.
An effective protection of our environment is largely dependent on the quality of the available information used to make an appropriate decision. Problems arise when the quantities of available information are huge and nonuniform (i.e., coming from many different disciplines or sources) and their quality could not be stated in advance. Another associated issue is the dynamical nature of the problem. Computers are central in contemporary environmental protection in tasks such as monitoring, data analysis, communication, information storage and retrieval, so it has been natural to try to integrate and enhance all these tasks with Artificial Intelligence knowledge-based techniques. This paper presents an overview of the impact of Artificial Intelligence techniques on the definition and development of Environmental Decision Support Systems (EDSS) during the last fifteen years. The review highlights the desirable features that an EDSS must show. The paper concludes with a selection of successful applications to a wide range of environmental problems. 相似文献
122.
CHEN Fei 《数字社区&智能家居》2008,(35)
随着嵌入式技术、网络技术和监控技术的发展,基于嵌入式技术的远程环境监控系统在安防领域将得到越来越广泛的应用。该文介绍了基于嵌入式技术的远程环境监控系统前端无线数据采集系统中PT2262/PT2272工作原理。 相似文献
123.
Optimization of anisotropic composite panels with T-shaped stiffeners including transverse shear effects and out-of-plane loading 总被引:1,自引:1,他引:0
J. Enrique Herencia Paul M. Weaver Michael I. Friswell 《Structural and Multidisciplinary Optimization》2008,37(2):165-184
A two-step method to optimize anisotropic composite panels with T-shaped stiffeners, including a new formulation of the transverse
shear properties and an approximation of the ply contiguity (blocking) constraints as functions of the lamination parameters
is provided. At the first step, a representative element of the stiffened panel (superstiffener) is optimized using mathematical
programming and lamination parameters subjected to combined loading (in-plane and out-of-plane) under strength (laminate or
ply failure), buckling and practical design constraints. Ply blocking constraints are imposed at this step to improve convergence
towards practical laminates. At the second step, the actual superstiffener’s laminates are obtained by using a genetic algorithm.
Results, for the case considered, show that the inclusion of transverse shear effects has an associated 2.5% mass penalty
and that neglecting its effects might invoke earlier buckling failure. In addition, the influence of designing for failure
strength at laminate or ply level is assessed. 相似文献
124.
张玉山 《数码设计:surface》2008,(2):184-186
当代环境陶艺不仅仅表达艺术家自身的情感以及对社会的关注,更多的是在对传统陶瓷技艺的继承与发扬的基础上,赋予陶瓷新的价值。本文从数字技术与印刷技术对环境陶艺的影响;陶艺雕塑成型与安装;可拆卸的陶瓷壁画与装置;室外整体烧成等四方面对环境陶艺的新技术进行了阐述。 相似文献
125.
Full instrumental rationality and perfect institutions are two cornerstoneassumptions underlying neoclassical models. However, in the real world, thesetwo assumptions never hold, especially not in developing countries. In thispaper, we develop a game theoretical model to investigate if relaxations inthe full instrumental rationality and perfect institutions premise can explainthe conflicts that have been occurring between the various principals in theNarok district in Kenya with regard to land tenure and use. 相似文献
126.
Dynamic planning model for determining cutting parameters using neural networks in feature-based process planning 总被引:1,自引:0,他引:1
Jaekoo Joo Gwang-Rim Yi Hyunbo Cho Yong-Sun Choi 《Journal of Intelligent Manufacturing》2001,12(1):13-29
Although feature-based computer-aided process planning plays a vital role in automating and integrating design and manufacturing for efficient production, its off-line properties prohibit the shop floor controllers from rapidly coping with unexpected production errors. The objective of the paper is to suggest a neural network-based dynamic planning model, by which the shop floor controllers determine cutting parameters in real-time based on shop floor status. At off-line is the dynamic planning model constructed as a neural network form, and then embedded into each removal feature. The dynamic planning model will be executed by the shop floor controllers to determine the cutting parameters. A prototype system is constructed to validate whether the dynamic planning model is capable of determining dynamically and efficiently the cutting parameters for a particular set of shop operating factors. Owing to the dynamic planning model, the shop floor controller will increase flexibility and robustness by rapidly and adaptively determining the cutting parameters in unexpected errors occurring. 相似文献
127.
研究了共坐键长的变化规律,提出了两个影响键长的参数,即配位体的半径与中心原子半径之比Rraio和由中心原子组成的基团拓扑指数F2,用BP神经网络法,逼近了50个、预测了11个简单无机分子中非含氢原子键的键长,其计算误差基本上在2pm以内。 相似文献
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