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91.
Conservation is a crisis discipline requiring rapid action with limited funds. This study examines the potential of socioeconomic variables to predict forest use values. If natural resource use can be predicted from socioeconomic data, conservation planners could rapidly identify and focus conservation programs on the sectors of local populations that most intensively utilize local flora and fauna. Families in three communities in the northern Peruvian Amazon were surveyed over a 6-month period. Data were collected on use of flora and fauna from six locally determined use categories (food, medicine and poisons, wood, weavings, adornments, and “other”) in forest types of three age classes (fallow fields—very young forests, young secondary forests, and old secondary forests). Forest use values were the dependant variables calculated in $/ha/year. Socioeconomic variables included: age, education, family size, residence time, land worked, land owned, number of fishing nets, chickens, pigs, cows, and/or mules owned (all proxies for productive assets), and level of ecological knowledge (ability of informants to correctly identify forest species and answer basic questions about their biology). Ordinary least square multiple regressions were run independently for each forest type. Regressions were also run separately for the two most valuable use categories, food and wood. Low R2 adjusted values (all < 0.3) reflect the difficulty in predicting human behavior due to confounding variables and complex interactions. Residence time and a household's community of residence were the most significant predictors of forest use values. Households in Vista Alegre, the community with the highest density of people and smallest landholdings per household, extracted the highest value of forest products per hectare. The longer a family stayed in any community the higher the value of forest goods they extracted. If families that lived in an area longest are the most intensive extractors of forest products, they should be a major focus for conservation programming. In addition, the higher value of products extracted from forests by some families may make them more open to strategies seeking to protect long-term viability of the resources they utilize. The importance of residence time also indicates that planners need to account for changes in the resource use patterns of stakeholders over time.  相似文献   
92.
Recent terrorist acts, in particular the 9-11 attacks in 2001, have created disruptions in the global economy. The short-term impact had been felt in the global tourism, airline industries, as well as the financial markets. While the global economy has recovered and is adjusting to the new global realities, the longer-term impact of heightened security risk across the world can be felt in the form of higher risk premiums in asset markets, as well as a shift of resources towards dealing with terrorism. Just as World War II had accelerated the development of nuclear energy as well as a major contributing factor in the genesis of Silicon Valley, the current war against terrorism will affect both the pace and trajectory of technology trends, as efforts are focused on developing technologies to combat terrorism. In this paper, we review the effects of the current war on terrorism in terms of its impact on the economy, the allocation of resources to R&D, and the trajectory of future R&D.  相似文献   
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The Kyoto Protocol foresees emission trading but does not yet specify verification of (uncertain) emissions. This paper analyses a setting in which parties can meet their emission targets by reducing emissions, by investing in monitoring (reducing uncertainty of emissions) or by (bilaterally) trading permits. We derive the optimality conditions and carry out various numerical simulations. Our applications suggest that including uncertainty could increase compliance costs for the USA, Japan and the European Union. Central Europe and the Former Soviet Union might be able to gain from trading due to higher permit prices. Emissions trading could also lower aggregate uncertainty on emissions.  相似文献   
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Summary. We analyze an oligopoly model of homogeneous product price competition that allows for discontinuities in demand and/or costs. Conditions under which only zero profit equilibrium outcomes obtain in such settings are provided. We then illustrate through a series of examples that the conditions provided are “tight” in the sense that their relaxation leads to positive profit outcomes. Received: April 7, 2000; revised version: September 14, 2000  相似文献   
98.
Gasoline divorcement regulations restrict the integration of gasoline refiners and retailers. Theoretically, vertical integration can harm competition, making it possible that divorcement policies could increase welfare; alternatively, these policies may reduce welfare by sacrificing efficiencies. This paper attempts to differentiate between these possibilities by estimating a reduced form equation for the real retail price of unleaded regular gasoline. I find that divorcement regulations raise the price of gasoline by about 2.6¢ per gallon, reducing consumers surplus by over $100 million annually. This finding suggests that current proposals to further separate gasoline retailing from refining will be harmful to gasoline consumers.  相似文献   
99.
Competition was introduced into the electric utility industry with the passage of the Public Utilities Regulatory Policy Act (PURPA) of 1978. Increasing interest has appeared in structuring the PURPA purchase market into an auction system. This paper addresses the design issues associated with setting up such markets and introduces a simulation model to study them. The simulation analysis is guided by theoretical issues such as the alleged inefficiency of first-price auctions. We find that efficiency concerns raised about first-price auctions turn out to be less important than simple theoretical concerns would suggest.  相似文献   
100.
王园  王彦亭 《时代经贸》2007,5(2X):30-31
遗传算法是一种宏观意义下的仿生优化算法,它模拟生物在自然环境中的遗传和进化过程而形成的一种自适应全局优化概率搜索算法。这种算法可以用于对海量的客户信息进行搜索,提取对决策有用的信息,让企业在激烈的市场竞争中处于有利地位,最终达到最高利润。本文还通过一个简单的实例研究将该算法应用在客户关系管理中。  相似文献   
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