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31.
In a market where consumers and the regulatory authorities are not fully informed about the actual production technology or environmental performance of firms that engage in strategic competition, I study the effect of environmental consciousness of consumers on firms׳ incentive to invest in cleaner technology. Firms compete in prices and may signal their environmental performance to uninformed consumers through prices. I also analyze the effect of an expected liability on firms in this setting. Compared to full information, incomplete information generates higher strategic incentive to invest in cleaner technology particularly when consciousness and/or expected liability are not too high. Requiring mandatory disclosure of technology or environmental performance may discourage such investment. Even though consumers and the regulator are uninformed, competition has a positive effect (relative to monopoly) on the incentive to invest.  相似文献   
32.
The level of rents attributable to natural resource producers depends on the risk faced by those producers. This paper argues that estimates of risk in mining should control for characteristics of firms such as diversification and debt financing. The capital asset pricing model is applied to securities of three Canadian nickel mining firms over the period 1961–1974. It is concluded that the level of risk was not unusually high.  相似文献   
33.
In Lepidoptera, female mating systems range from strict monandry to strong polyandry. Males transfer an ejaculate during copulation that contains both sperm and accessory gland substances. In butterflies the male ejaculate has at least three effects: it (1) contains sperm that can fertilize the eggs of the male’s mating partner, (2) influences the refractory period of the mated female, and (3) contains nutrients that can be used by the female to increase her reproductive output. A number of recent studies have shown that males in polyandrous mating systems are endowed with adaptations to increase mating capabilities. Relative to males in more monandrous species they transfer larger first ejaculates which contain relatively more protein, and allocate proportionally more resources to reproduction. The objective of this study was to compare male reproductive investment in successive ejaculates, in terms of both mass and quality, to determine if males of polyandrous species are capable of maintaining the production of larger and more nutritious ejaculates than males of more monandrous species. We used three species of pierid butterfly, with mating systems ranging from relative monandry to polyandry. The degree of polyandry had a substantial effect on the reproductive performance of males. The cumulative protein content of ejaculates increased with the degree of polyandry. Only males of the most polyandrous species, Pieris rapae, produced three successive ejaculates of similar mass and protein content. In the relatively monandrous species, Aporia crataegi and P. brassicae, males in subsequent matings never produced another ejaculate as large as that transferred by males mating for the first time, although the protein content (mg) of ejaculates did not differ in second and third ejaculates. Moreover, the ability to remate varied with the degree of polyandry. Given the opportunity to remate, the majority of P. rapae males mated three times, whereas relatively few A. crataegi and P. brassicae males were able to perform three matings. These results suggest that male capacity to produce large, nutritious ejaculates is limited in relatively monandrous species. In this study only males belonging to the most polyandrous species had the ability to recuperate quickly from a mating event and remate. Our results suggest that males in polyandrous systems are better adapted to mating more than once. Received: 3 November 1995/Accepted after revision: 13 July 1996  相似文献   
34.
This paper discusses the development impact of mining and mineral processing on the regions in which they are located. The discussion is organized so as to be of relevance for policy formulation in resource-rich developing countries which consider the exploitation of their mineral wealth. The hypothesis is that mining technology, interpreted in a broad sense, has undergone a profound change since 1900. In consequence, experiences of mineralbased regional development in the industrialized countries around the turn of the century are of little relevance to the Third World in the 1980s. Contemporary mineral ventures have very weak regional development repercussions in the absence of forceful policies specifically directed towards the regional development goal.  相似文献   
35.
从环境污染汉理投资的相关因子和系数分析入手,对治理投资质量和效果分别建立了量化函数关系,由此计算所得结果与理论标准值比较,则可确定其质量与回报结果。  相似文献   
36.
针对我国环保产业发展中的不足之处,剖析了环保产业在发展方向、科技含量及发展条件等方面存在的误区,并提出了相应的对策和建议  相似文献   
37.
张佳华  王伟 《上海环境科学》1998,17(11):14-16,19
从模糊分析的基本概念出发,采用“主因素决定型:的综合评综合方法,提出了环保基金效益分析模糊隶属度原则,建立了保投资效益分析的模糊数学模型,通过实例分析表明:(1)环保基金投分析应选择污染投资费比,污染物削减费比,污染物处理效益和污染物去除率4个综合指标;(2)应用模型的预测功能,对年度早报的污染物治理项目优劣进行效益分析筛选,排序,为科学合理的编制年度计划提供依据。  相似文献   
38.
通过回归分析法研究造纸与印刷业上市公司的环保投资与财务绩效的相关性,发现两者之间呈显著的正向线性关系。将环保投资按不同结构分类,发现污染预防投资比末端治理投资带来的财务绩效更明显,环保固定资产投资比技术投资在短期内带来的财务效益更明显。  相似文献   
39.
The main objective of this paper is to compare indicators based on energy consumption and financial savings to rank strategies to save potable water in buildings. The method is based on potable water savings, embodied energy, energy consumption for operation, and investment feasibility analysis; and it was applied to a school in the city of Florianópolis, southern Brazil. The strategies considered to save potable water were rainwater, greywater, water-efficient appliances, and their combinations. The embodied energy was estimated using indices of embodied energy per mass of material, and labour. The indicators used to rank the strategies were potential for potable water savings, index between potable water savings and embodied energy or total energy consumption, net present value, internal rate of return, discounted payback, and index between potable water savings and initial costs. All strategies and combinations were feasible, but the use of water-efficient appliances was the best. Amongst the indicators used to rank the strategies, five of them led to the same ranking. Such indicators can be applied to rank potable water saving strategies in other types of buildings and climates.  相似文献   
40.
关于公共交通基础设施投资建设的研究目的是降低汽车密度 ,从而使公共交通事故减少。笔者主要研究如何进行投资建设 ,使公共交通客流按照一定的增长率增长 ,不至于引起客流较大的波动 ,保障人们出行的安全。首先 ,建立投资控制模型 ,分析其能控性和稳定性 ;由于该系统不是渐进稳定 ,投资策略只能采用有状态反馈的极点配置策略 ;采用待定系数法得出投资策略的数学表达式。最后 ,对结果进行验证并分析策略的优缺点。得出以下两个结论 :即在该投资策略下 ,系统在两步之内便逼近目标 ,有快速反应的品质 ;若需求在短时间内按照给定的规律增长 ,必须加大投资力度。笔者还给出展望和建议。  相似文献   
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