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31.
Models of strictly rational choice assume that decision-makers evaluate options on relevant dimensions, assign fixed values to options, and then make consistent choices based on these values. If so, recent experience would have no impact on preference. But, recent events change an animal’s state, and preference may change accordingly. We explore how state affects willingness to accept greater danger to obtain larger food rewards. We tested how a supplement in state (hoard size) impacts this willingness in gray jays (Perisoreus canadensis). When subsidized, most of the subjects increased their willingness to trade danger for food. Why would they become less cautious when their hoard was increased? Superficially, it might seem prudent to play it safer in response to a subsidy. But imagining fitness as a sigmoid function of state (hoard size) provides a tentative explanation for our counterintuitive finding. Above a threshold hoard size, a subsidy should weaken the willingness to accept extra danger. Incremental increases in state in the deceleratory phase yield smaller fitness gains, so it would pay to increase emphasis on safety after receiving a subsidy. But below this threshold, incremental increases in state in the acceleratory phase yield bigger fitness gains, and so it would pay to decrease emphasis on safety after receiving a subsidy. Most of our subjects’ choice behavior was, thus, plausibly consistent with the possibility that effective hoard size is considerably smaller than the total number of items stored. We speculate that this response may reflect an ecologically rational compensation for the inevitable loss of hoards via theft and rot.  相似文献   
32.
Improving the performance of the state environmental agencies (SEAs) necessitates an effective institutionalization of governmental environmental management functions. There are examples of successful and unsuccessful SEAs in several parts of the world. Analysis and assessment of these cases can deliver useful insights for institution builders. The objective of this article is the assessment of the institutional effectiveness of the SEAs in Turkey through the perceptions of the experts using the Delphi Technique. In this regard, a checklist is developed including 16 criteria and 123 subcriteria to measure the institutional effectiveness of the SEAs. Twenty-eight national and international experts have formed a Delphi panel and evaluated the national and local conditions. Results, based on the perceptions of the experts, indicate that the overall effectiveness of the SEAs is far less than satisfactory. Negative consensus has been reached over the effectiveness of 13 of the16 criteria and 95 of the123 subcriteria; however, no consensus has been achieved over the remainder of the parameters. The survey has also proven that the Delphi Technique can be effectively used for that purpose. Utilization of the checklist method is also useful in diagnosing the problematic components of the SEAs. It is recommended that this approach be used in similar cases elsewhere.  相似文献   
33.
在出水基质浓度Ce,沼气产生速率Qg对进水基质浓度C0序列的传递函数模型的基础上,采用卡尔曼滤波法对Ce和Qg序列进行估计和预测,标准误差分别为6.19%和10.4%。  相似文献   
34.
淮阴区大气降尘污染状况探讨   总被引:1,自引:0,他引:1  
韩静 《环境科技》2006,19(Z2):79-80
根据淮阴区多年监测的降尘数据,对淮阴区降尘量进行了统计分析,找出了淮阴区近几年来降尘的变化规律;利用方差分析方法检验了不同季节降尘的显著性差异,发现春季降尘量最大;找出了不同功能区降尘变化状况,发现交通区的降尘量最大。最后根据秩相关系数法进行了分析。结果表明,淮阴区降尘是呈下降趋势变化。  相似文献   
35.
武汉虹TH-3000微电脑大气污染日平均浓度采样器与美国Dasibi公司生产的Dasibi1000型大气自动监测系统,监测方法不同。本文对两系统监测SO2、NO2、结果进行对比分析,表明:①两种监测系统测定SO2和NO2都具有很好的线性关系;②测定结果之间存在着显著性差异;③两种监测系统间存在着系统误差;④SO2测定结果不具有相同的精密度,而NO2却具有很好的精密度;⑤两种监测系统监测SO2和NO2的平均偏差较大。  相似文献   
36.
ABSTRACT

The large share of carbon emitted by energy-intensive industries in the extraction and processing of basic materials must be limited to decarbonise society and the economy. Ways in which the state can govern industrial decarbonisation and contributes to green state theory are explored by addressing a largely ignored issue: the green state’s industrial relations and its role in industrial governance. With insights from a Swedish case study, the tension between the state’s economic imperative and ecological concerns in greening industry are shown to persist. However, as the energy-intensive industry’s previously privileged position in the economy is weakening, industry is opened to decarbonisation strategies. While the case exposes a number of governance challenges, it also suggests potential areas where the state can pursue decarbonisation in energy-intensive industry and points the way to an active role of the green state in governing industrial decarbonisation and greening industry.  相似文献   
37.
State variables in many renewable resource management problems, such as the abundance of a fish stock, are imperfectly observed over time. In systems characterized by state uncertainty, decision makers often invest in monitoring to learn about the level of a stock. We develop a stochastic bioeconomic model of marine invasive species management under state uncertainty. The decision maker in our model simultaneously evaluates optimal investment in monitoring and population control. Using a recently-devised method for solving continuous-state Partially Observable Markov Decision Processes (POMDPs), we find that the ability to learn through monitoring can alter the role of population control in the optimal policy function, for example by reducing control intensity in favor of monitoring. Optimal monitoring depends on the management context, including in our application lionfish population structure. The rich transient dynamics of our model depend critically on the relationship between the initial conditions for information and invader abundance.  相似文献   
38.
This study examines the present environmental and socio-economic status of Adiabo Community in Odukpani Local Government Area of Cross River State against the background of the proposal of the Cross River State Government to site a tourism resort in the community. The paper utilizes participatory appraisal techniques to document information on the existing environmental and socio- economic structure of the study area. It also analyses the potential effect of the proposed tourist resort on the community dwellers and finally recommends strategies to ensure the sustainability of the proposed project and livelihood activities of the natives in the study area.  相似文献   
39.
Environmental auditing: Theory and applications   总被引:3,自引:0,他引:3  
The environmental audit has become a regular part of corporate environmental management in Canada and is also gaining recognition in the public sector. A 1991 survey of 75 private sector companies across Canada revealed that 76% (57/75) had established environmental auditing programs. A similar survey of 19 federal, provincial, and municipal government departments revealed that 11% (2/19) had established such programs. The information gained from environmental audits can be used to facilitate and enhance environmental management from the single facility level to the national and international levels. This paper is divided into two sections: section one examines environmental audits at the facility/company level and discusses environmental audit characteristics, trends, and driving forces not commonly found in the available literature. Important conclusions are: that wherever possible, an action plan to correct the identified problems should be an integral part of an audit, and therefore there should be a close working relationship between auditors, managers, and employees, and that the first audits will generally be more difficult, time consuming, and expensive than subsequent audits. Section two looks at environmental audits in the broader context and discusses the relationship between environmental audits and three other environmental information gathering/analysis tools: environmental impact assessments, state of the environment reports, and new systems of national accounts. The argument is made that the information collected by environmental audits and environmental impact assessments at the facility/company level can be used as the bases for regional and national state of the environment reports and new systems of national accounts.  相似文献   
40.
A consequence of expanding residential development into rural areas is the potential alteration of ecological communities. Certain novel land-use policies seek practical solutions by accommodating social needs for housing while conserving biodiversity. This study investigates whether regulations designed to protect the aesthetic characteristics of a river corridor simultaneously mitigate negative effects of development on avian biodiversity, despite the absence of explicit conservation objectives. Using housing data from the US Census (1990 and 2000) and the Audubon Christmas Bird Count (1987–2000), we examined changes in housing density, avian communities, and the relationship between these two variables in a location that has adopted aesthetic landscape planning, the Lower Wisconsin State Riverway. We found that overall species diversity increased in the Riverway, but remained constant in reference areas, although the relative increase in housing density in the two areas did not differ. We also found that omnivore populations decreased in the Riverway and increased in reference sites. On the whole, our study provides preliminary evidence that aesthetic landscape planning, such as employed in the Lower Wisconsin State Riverway, might constitute a politically viable approach to conserve ecological resources.  相似文献   
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