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41.
设计了一个烧结模糊控制系统,进而构建了一个基于模糊控制的自适应脉宽控制器,对煤气阀、换向阀开关时间进行控制;利用模糊控制器的模糊推理能力来实现煤气阀门开度在线调整,以达到优化控制的目的。运行结果表明,这种控制器与常规比值控制器相比可以取得较好的控制效果。 相似文献
42.
Donald Kimball 《中国与世界经济(英文版)》2005,(4)
I. IntroductionNations at every stage of development and in every region of the world are more closelylinked through trade in goods and services, through flows of funds and investments ineach others’ economies than ever before. But in sharp contrast to more and more nationsloosening restrictions on international trade, controls over capital flows are still substantialnearly everywhere except in the most developed economies. This is certainly the case inChina, where restrictions on movements … 相似文献
43.
Walter Block 《Journal of Business Ethics》2002,40(1):75-90
Rent control is an economic abomination. It diverts investments away from residential rent units, it leads to their deterioration, it is responsible for urban decay such as in the South Bronx, it does not help poor tenants, it is a horrendous means of income redistribution. Yet this economic regulation is beloved of intellectuals (hot beds of pro rent control sentiment are Berkeley, Ann Arbor and Cambridge) particularly in the legal and philosophical communities. The present article is dedicated to an exploration and rejection of the arguments in behalf of rent control which emanate from this source. 相似文献
44.
近几年的几场局部战争部分表明了现代军事航天系统的重要性。本文主要介绍了美国最重要的一个军事航天测控网--空军卫星控制网的情况,希望能对了解美国军事航天测控体制有所帮助。 相似文献
45.
油井水泥产品质量现状分析 总被引:1,自引:0,他引:1
结合2000~2005年对各油田油井水泥的质量监督工作,对我国油井水泥使用的标准、产品工艺、产品质量现状进行了分析。 相似文献
46.
47.
Haluk Emiroglu 《International Journal of Consumer Studies》2002,26(3):198-209
This paper addresses the following subjects: biotechnology and consumers, concern about risks, consumer acceptance, labelling of foods produced using biotechnology, the legal approach to consumer protection, and consumer protection policies relating to biotechnology products in the European Union, the United States, Turkey and global institutions such as the Convention for Biological Diversity (CBD) and the World Trade Organisation (WTO). It is likely that biotechnology will gain ground much more rapidly in the twenty‐first century than in the past. Despite rapid, detailed and precise advances in gene technology, its applications have not been the received with a great deal of consumer enthusiasm. Consumers have approached genetically modified foods with considerable apprehension and opposition. Consumer concerns about bioengineered food products focus on the questions of human health, environmental and social risks and benefits. The most important stages in the process of marketing new foods produced using biotechnology are to demonstrate user need and consumer acceptance. Generally, the technical complexity of biotechnology makes it difficult for consumers to understand details of the product and the specific attributes of biotechnology applications. Scientific uncertainty, the nature of consumer concerns and general reluctance to accept biotechnology products, increase the importance of consumer protection. Legal protection is a very important factor in the solution of new social problems related to technological advances. More specifically, consumer and environmental law support consumer protection related to foods produced with biotechnology. The basic principles of consumer law can be re‐formulated as consumer rights. Environmental law is a new phenomenon, but precautionary principles and public participation in decision‐making for environmental law are relevant to consumer protection relating to bioengineered food products. 相似文献
48.
Hypotheses which relate top-level managers' age, years of company and industry service, and education to strategic change are studied with a sample of 855 managers from 27 railroads. Results generally support hypotheses that younger managers and those with less experience are more likely to alter their strategies with changing environmental conditions. 相似文献
49.
Doede Wiersma 《Environmental and Resource Economics》1991,1(1):63-82
A great deal of the economic literature on pollution control strategies concentrates on the efficiency of environmental policy instruments. Most analytical studies in this field show that market instruments are more efficient with respect to the cost of pollution abatement of a given number of polluters than non-market instruments. According to several analytical studies, market instruments should also be more efficient with respect to innovation in pollution abatement equipment than non-market instruments. In the empirical literature a great number of case studies exist with estimations of the savings of abatement costs of market instruments in a situation without technological progress. Empirical studies about the impact of environmental policy market instruments on the abatement costs in situations with technological progress are lacking.The purpose of this paper is to fill this gap. The paper deals with an empirical estimation of abatement costs for the emission of SO2 of coal-fired electricity units in the Netherlands from 1985 to 2000. First, the working of market instruments and non-market instruments (the existing environmental policy of the Dutch government) is simulated in a static situation. Second, we analyse the learning effects of flue gas desulphurization. The efficiency advantage of market instruments turns out to be larger in a situation of technological progress than in a static situation. 相似文献
50.
张文驹 《中国国土资源经济》2003,16(2):4-7
从自然资源投入产出关系分析入手 ,论述了资源产业的两大产业群———资源开发业与资源再生产业 ,揭示了其内外经济关系。 相似文献