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131.
This paper examines a scheme of economic incentives for environmental protection, in which spatially differentiated pollution taxes are in use in compensating the pollution abatement costs. A simple mathematical model is described which determines an incentive system that encourages polluters to reduce the discharges to an acceptable level of ambient quality standards in a cost-effective manner. It is shown that the vector of pollution charges has to be proportional to the marginal abatement cost vector, but is smaller than the latter in magnitude. It is demonstrated that a necessary incentive effect may be achieved even if the total pollution charge is much lower (about three times) than the total abatement costs. It is also estimated how this charge incentive system reconciles conflicting criteria of cost-effectiveness and of equity. These conclusions are verified by numerical experiments with real data.  相似文献   
132.
随着互联网的迅猛发展和广泛应用,日趋严重的网络信息安全问题,对政府管制提出了更为复杂和系统的要求,在此情况下,如何管制"爆炸式"发展的互联网,既使宪法所赋予公民的言论自由可以在网络上充分且方便地享有,又能够抑制侵害他人、国家乃至社会自由和效率的不正当行为,这成为摆在中国政府面前的一项重要课题.本文分析了网络信息安全与政府管制的关系,提出了网络信息安全政府管制的政策选择.  相似文献   
133.
王文哲  李真燕 《价值工程》2005,24(3):105-108
对公司的竞争力做评价时要借用大量的财务指标,然而这些财务指标在给予我们大量信息的同时也增加了分析问题的复杂性。考虑到各个财务指标之间存在着较大的相关关系,我们可以考虑使用因子分析方法,用几个不相关的综合指标来代替所有的财务指标。本文采用因子分析对我国家电上市公司做了全面的竞争力评价分析。  相似文献   
134.
We examine the two traditions of content analysis: the first in which one substitutes words of a text with categories, and the second in which one looks for clusters of words that may refer to a theme. In the first tradition, preexisting dictionary categories give meaning to the words; in the second, meaning comes after the fact. Preexisting dictionary categories (the substitution model) are calibrated instruments applied within experimental designs that leave no space for doubt; meanwhile, the ability of the correlational model to conjure up complex themes from fragments of a text yields no unique solution. These differences have bearings on the production of new social knowledge. We expound on the epistemological foundations of the two traditions of interpretation and draw from them decision rules upon which one may rely for choosing among appropriate content-analytic tactics. Two reasons make this essay timely and critical: (1) the increasing variety of new content-analyticsoftware for particular purposes and (2) the almost exclusive focusing on software and technology at the expense of adjusting the choice of the software to the nature of the text. Two studies, one in historiometry, the other in autobiography, illustrate the liabilities and benefits of the two models of content analysis.  相似文献   
135.
欧阳忠 《企业技术开发》2005,24(6):40-42,67
文章针对公路桥梁,利用有限元方法分析在地震载荷下的应力分布规律,为桥梁抗震设计提供依据。  相似文献   
136.
Chi-Yo  Joseph Z.  Gwo-Hshiung   《Technovation》2007,27(12):744-765
Since the year 2000, silicon intellectual property (SIP), which can minimize the gap in ‘design productivity’ that exists with systems-on-chip (SOC), has become one of the most important factors in the development of integrated circuit (IC) products in the SOC era. Although SIP is very important for IC industry development, complicated business, technical as well as legal issues inside SIP transactions have hindered successful transactions and the integration of SIPs into SOCs. Thus, web-based SIP e-Commerce mechanisms, called SIP Malls, have emerged, aiming to resolve complex SIP issues. To maintain its leading position and competitiveness in the World's IC industry, as well as the value added by SOC products in Taiwanese IC firms, the Taiwanese government has developed SIP Malls, using innovation policy tools. However, the Taiwanese SIP Mall industry remains immature. No existing Taiwanese SIP Malls generate a profit or account for a significant share of worldwide SIP transactions. This research will develop an analytical framework for defining an innovation policy portfolio that aims to develop Taiwan's SIP Mall industry, so that it will enhance the value added of SIP Malls and, thus, the nation's competitiveness in the SIP and IC industries, something which already has become one of the Taiwanese government's major concerns. The industry innovation requirements (IIRs) are summarized using the Delphi method. Meanwhile, the major IIRs identified by Decision Making Trial and Evaluation Laboratory (DEMATEL) are introduced. After the IIRs are derived, the relationships between the IIRs and innovation policy tools are derived by Grey relational analysis (GRA). Then, the innovation policy tools are clustered, based upon the Grey grades derived by GRA. Finally, reconfigured innovation policy portfolios are presented for the Taiwanese government's policy definition. The results demonstrate that developing an innovative policy portfolio that includes scientific, technical, educational, public enterprise, information, legal and regulatory, financial, and taxation policy tools will be the most necessary step towards developing Taiwan's SIP Mall industry.  相似文献   
137.
广州南沙港发展现代物流业的SWOT分析及对策研究   总被引:1,自引:0,他引:1  
陈勇  赵一飞 《物流科技》2006,29(3):51-53
本文用SWOT分析法时广州南沙港发展现代物流业的优劣势以及面临的机遇和挑战进行了综合分析,并就如何做强南沙港物流业提出了相关对策。  相似文献   
138.
谭斌华 《企业技术开发》2007,26(5):22-24,84
地下管线的主要特点是隐蔽性,地下分布纵横交错,年代已久的原有手工数据几乎无参考价值且存档不便、使用复杂、工作量大。使用自主开发升级后的计算机程序软件,不仅可以大大提高地下管线测量数据的更新、规划设计及施工的效率,而且可以通过CAD图形分析对特殊地段重要管线是否保留利用作出决定。  相似文献   
139.
三维激光扫描仪在地形测量中的应用   总被引:4,自引:0,他引:4  
张宏  胡明 《企业技术开发》2007,26(8):16-19,25
文章从三维激光扫描仪在测量中的作用入手,详细介绍了三维激光扫描仪的工作原理和三维激光扫描系统,并说明了三维激光扫描仪配套三维数据处理软件的功能,着重介绍了三维数据的处理方法:点云的连接、特征线的提取、对地物的三维建模(TIN建模),在TIN建模中,介绍了狄洛尼三角网的构网方法。  相似文献   
140.
Improving productive efficiency is an increasingly important determinant of the future of the swine industry in Hawaii. This paper examines the productive efficiency of a sample of swine producers in Hawaii by estimating a stochastic frontier production function and the constant returns to scale (CRS) and variable returns to scale (VRS) output-oriented DEA models. The technical efficiency estimates obtained from the two frontier techniques are compared. The scale properties are also examined under the two approaches. The industry's potential for increasing production through improved efficiency is also discussed.  相似文献   
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