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971.
The aim of this paper is to analyse one of the principal problems in primary health care management: the evaluation of efficiency in primary health care centres. Given the special characteristics of measuring outcome in primary care it is necessary to evaluate the performance of centres from a quality perspective too. The methodology used, DEA (Data Envelopment Analysis), allows us to introduce quantitative and qualitative variables in a sample of primary care centres in a Spanish province. Once the efficiency of the different centres is known, we investigate the sensitivity of the methodology to changes in the definition of outputs used.  相似文献   
972.
Linking forestry, sustainability and aesthetics   总被引:1,自引:0,他引:1  
In forest planning, little research has been devoted towards examining how visual-impact assessment can improve the public acceptance of forest activities and augment forest sustainability. The objective of the present work is to review the methods of aesthetic assessment of forest landscapes, which will help the implementation of visual-impact assessment in sustainable forestry. From the numerous techniques of landscape evaluation that have been devised in recent years, the expert approach techniques have dominated in environmental management practices and the perception-based approach in research. The non-market economic valuation techniques are essentially trade-off methods and not aesthetic assessments by themselves. Revealed preference methods, such as hedonic-price, use actual market choices of individuals to get their preferences towards non-market attributes, and stated preference methods, such as contingent valuation method, rely on surveys to get directly the individual's willingness to pay for the non-market attributes. Psychophysical preference modelling is a popular quantitative holistic technique of landscape evaluation and if used in combination with indirect aesthetic evaluation methods might create new standards and protocols for techniques of objectively estimating public perception of aesthetic quality and thus to enhance social sustainability in forest space.  相似文献   
973.
As the focus of environmental policy and management shifts from cleaner production at the process level towards greener products as a whole, stakeholders ask for transparency throughout the entire value chain. This article assesses the comprehensiveness and the value of currently reported quantitative environmental disclosures of 97 listed companies from the automotive, banking, pharmaceutical and electronic hardware sectors. Findings indicate that quantitative environmental disclosures have many limitations, including incompleteness and inconsistency regarding corporate activities and sites, and limited internal data coherence. For many sectors, corporate disclosures only cover a very small share of the total environmental burden of products. A stepwise procedure is proposed to verify and improve the quality and completeness of reporting using life cycle approaches. We present simple data quality tests, and we introduce the concept of the environmental influence matrix, which provides a solid basis for the identification and prioritization of key performance indicators and areas of action. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.  相似文献   
974.
简要介绍水环境研究所组建近10年来取得的主要科研成果。其创新性研究工作主要体现在:(1)水环境监测与标准化体系建设。实现了从常规污染物监测到技术难度较大的痕量有毒有害污染物监测的转变,水质监测技术实现了标准化;(2)水环境保护与水污染控制。开展了水环境演化机理、水环境污染模拟及水污染修复等理论的研究与实践;(3)水利水电工程的生态环境影响研究。着重关注了重大水电工程因改变水文情势所引发的生态与环境问题,为我国重大水利工程的规划设计和运行管理提供了技术支持;(4)饮用水安全保障。研究了饮水安全保障技术及相关设备;(5)水环境综合管理。研究了基于3S技术的水环境信息管理技术,协助业务主管部门开展了大规模的水环境状况调查,取得了多项创新性成果。最后提出了水环境研究今后的展望。  相似文献   
975.
We examine the interaction between internal control assessments and substantive testing in a model of fraud detection. The purpose of our study is to examine a two‐stage model of the auditor‐manager interaction in which the auditor assesses the “likelihood” or possibility of fraud in the first stage and conducts substantive tests in the second stage. We examine the allocation of audit resources across these two distinct facets of the audit. We find that, regardless of the auditor's allocation, the probability of undetected fraud remains the same, but the allocation of some audit resources to internal control assessment may provide cost savings for the auditor.  相似文献   
976.
As many cases studies show, successful public health measures are being implemented in many places around the globe, and country-level mortality has fallen significantly in recent decades in all but a few countries. Are the two linked? Does development assistance for health (DAH) improve, on balance, recipient countries’ mortality trajectory? Using a new data source containing DAH on 96 high mortality countries, the regression analysis shows no effect of DAH on mortality. Other types of aid, including water development, also have no effect. Economic growth, on the other hand, has a strong negative effect on mortality. These findings confirm and build upon recent work by Williamson (2008) and are shown to be robust to a variety of sensitivity analyses and alternative model specifications and estimation methods.This analysis also shows that the effectiveness of DAH has not increased over time, even as the level of that funding has increased fourfold, though spending on infectious diseases and family planning may have caused small reductions in mortality. Furthermore, even though it is encouraging that DAH has tended to go where the need is highest, it also goes to states that have experienced the greatest mortality reductions in the recent past. In other words, DAH appears to be following success, rather than causing it.  相似文献   
977.
978.
979.
河流系统的连通性是维持河流生态系统健康的重要因素。基于图论连通度理论,将河道-滩区系统中的水流通道、鬃岗地形、小型封闭水域和牛轭湖等微地貌单元概化为图模型,并利用ArcGIS平台和DEM模型实现其表述。在此基础上,建立图的邻接矩阵,进行连通性分析和水流通道连通度计算,实现了河道-滩区系统连通程度分析的定量化。最后以瓯江丽水河段的河道-滩区系统为例,进行了一定水位条件下的连通状况模拟和连通程度定量分析。案例分析结果表明:通过确定关键性水流通道和水流通道汇合点,可对河流生态修复工程设计方案进行优化;利用本文所提出的方法对河道-滩区系统的连通性进行定量评价是有效可行的。该方法可用于河流健康评估、河流生态修复工程优化、河湖水网连通程度的定量分析等。  相似文献   
980.
集约化农业生产所带来的环境影响和健康危害已经使人们逐渐认识到建立可持续农业发展途径的必要性。随着人们收入的增长,城市化的迅速发展成为消费模式转变的最为显见的驱动力。揭示在考虑到可持续发展的风险和不确定性的情况下对未来农业生产规划的预测,和在决策过程中恰当的风险指标,而这些内容的引入将极可能改变与畜产品设备配置和集约化程度相关的未来政策。以中国为例,研究主要目标为:(1)阐明如何将风险指标引入到决策过程中从而避免健康风险带来的负面结果;(2)阐明如何在农业生产规划中明确风险和不确定性,以达到可持续农业发展。  相似文献   
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