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941.
Summary The paper discusses several aspects of the practical application of the SAR. It is shown that the unit is an ideal solution for basic research and laboratory experiments. SAR is directly nonmeasurable unit. Although methods and devices based upon indirect SAR measurements may widen our knowledge about EM energy distribution and absorption within a body. It is shown that for practical applications the temperature SAR measurement methods are not sensitive enough while methods based upon E(H) measurement are less accurate than traditional approaches. As a result of assumption SAR = 4 W/kg as a basic restriction the present protection standards are illogical and nonrealiazable. A return to traditional units (E, H, S) in the standards and surveying metrology is suggested.  相似文献   
942.
Reintroduction of wood in rivers for restoration purposes is now recognized in a positive way by scientists. Nevertheless, the perception of wood in riverscapes is strongly affected by the socio-cultural environment. This cultural influence might explain why wood reintroduction is accepted and promoted in some regions of the world but not in others, despite the demonstrated ecological benefits. From an extensive student perception survey, we show that most of the groups from nine countries in the world considered riverscapes with wood to be less aesthetic, more dangerous, and needing more improvement than riverscapes without wood. By contrast, this way of thinking was not observed in Germany, Sweden, and Oregon (USA), where the first instances of wood reintroduction occurred.  相似文献   
943.
Integrated Approaches in Urban Storm Drainage: Where Do We Stand?   总被引:1,自引:0,他引:1  
Integrated approaches to urban stormwater drainage management are being increasingly advocated as necessary for advancing more sustainable and holistic management of urban water environments. In this paper, the status of integrated approaches in the management of urban stormwater discharges to receiving waterways is summarized. The starting point of the paper is with the recent scientific contributions, revealing that integration is being pursued and implemented predominantly at two conceptual levels. These include 1) integrating the technical system with the receiving waterway environment, and 2) considering the interaction and influence of the human system with the technical system through processes such as stakeholder and public participation. Additionally, it is argued that the evolving shift towards the implementation of water-quality-based strategies advances the need for further development and application of integrated models and approaches. The cases of online physically based models for predictive control and integrated source control and public participation are presented as examples of such ongoing developments in pursuit of integrated urban stormwater management.  相似文献   
944.
- Triggered by the detection of a large variety of pharmaceuticals in surface waters, soils and groundwaters across the world (e.g. Halling- Sørensen et al. 1998, Daughton & Ternes 1999, Jones et al. 2001, Heberer 2002) and the widespread occurrence of endocrine active compounds and related effects in the environment (e.g. Purdom et al. 1994, Tyler et al. 1998, Vethaak et al. 2002), pharmaceuticals in the environment have become an issue for both the scientific and the public community. During the last few years, our understanding of the fate and effects of pharmaceuticals in the environment has progressed significantly. However, there are still a number of uncertainties concerning the effects of pharmaceuticals on the environment and the assessment of potential exposure (e.g. Hanisch et al. 2004, Salomon 2005). These uncertainties will be addressed by the EU-project ‘Environmental risk assessment of pharmaceuticals’ (ERAPharm). This project, a specific targeted research project, is carried out within the priority ‘Global change and ecosystems’ of the 6th framework programme of the European Union. ERAPharm has started on 1st October 2004; the project duration is three years.  相似文献   
945.
ABSTRACT/ The aim of this study is to analyze the antecedents of urban waste recycling behavior. To achieve this goal, a concrete urban waste management program was chosen. The study focuses on the Selective Collection Program (SCP) in Zaragoza, a medium-sized city in northeastern Spain. The research starts with a conceptual model in which the variables that potentially affect recycling behavior can be classified into two groups: incentives and barriers. Moreover, the sociodemographic characteristics of the individuals are included in our study. Given that the proposed model requires specification of latent variables or constructs, the analysis is based on the Structural Equation Models (SEM) methodology. The results revealed that environmental awareness, knowledge of the environmental impact of urban waste, and the positive perception of management by local government exercise a positive effect on individual recycling behavior, while perceived personal difficulties (space and time availability) and distance to and from the container have a negative effect. As regards sociodemographic variables, this study found that annual family income sustains a negative relationship with recycling behavior, while age maintains a positive one. The results obtained clearly show the important role that the public authorities play, especially municipal governments, in achieving the waste recycling objectives established in accordance with international legislation.  相似文献   
946.
The need to compare potential health risks to the public associated with different activities that can result in releases of hazardous substances to the environment is becoming increasingly important in decision-making. In making such comparisons, it is desirable to use equivalent indicators of potential health risks for radionuclides, chemical carcinogens, and noncarcinogenic hazardous chemicals. Current approaches to risk assessment that were developed for purposes of protecting human health do not provide equivalent indicators of potential risks from exposure to radionuclides and hazardous chemicals. Comparisons of environmental concentrations or calculated exposures or risks with standards for protection of public health also do not provide equivalent indicators of potential risks. We propose a simple approach to comparative risk assessments in which calculated exposures to any hazardous substances are expressed relative to no-observed-effect levels (NOELs) or, preferably, lower confidence limits of benchmark doses (BMDLs) in humans. This approach provides an equivalent, science-based indicator of the relative risks posed by different exposures to any hazardous substances.  相似文献   
947.
Over the last decade or so, rural housing problems in Britain have become an important focus of attention both for researchers and planners. Inaccessibility to adequate housing is a significant component of the more all‐embracing problems of rural deprivation. The rented sector is of particular relevance to the amelioration of these problems, but the supply has been increasingly restricted both in the private and in the public sector. Great stress has therefore been laid on the ability of housing associations to provide rented sector housing. This paper investigates the work of one particular housing association in Mid‐Wales — Cymdeithas Tai Dyffryn Teifi (CTDT) and assesses the degree of complementarity achieved with housing provision by the local councils operating in the same rural locality. The particular areas of effectiveness of a housing association in this context are thereby evaluated.  相似文献   
948.
A planning and decision-making framework for ecological restoration   总被引:2,自引:0,他引:2  
A broad and objective perspective of ecological and socioenomic knowledge is required to underlie a scientific approach to the problems of terrestrial restoration ecology. Uncertainty associated with limited scientific knowledge highlights the crucial importance of the interaction between science and policy in weighing ecological restoration alternatives in relation to other management options. In this paper, we provide a pragmatic definition for restoration ecology that is suitable for extensive terrestrial applications and present a decision framework to help organize and clarify different phases of the decision process as it is related to ecological restoration. We argue that restoration planning should include a wider spectrum of participants and decisions than have traditionally been employed.  相似文献   
949.
环境中五氯酚监测研究进展   总被引:4,自引:0,他引:4  
冯亚平 《四川环境》1992,11(1):23-26
本文概述了五氯酚(PCP)的环境污染、人群暴露水平及目前有关监测方法研究进展。环境污染主要来源于本品的生产及工农业中的应用。在我国主要广泛用于杀灭血吸虫的中间宿主——钉螺。人体通过污染的空气、水体及食品可摄入PCP造成生物蓄积,危害健康。监测方法有化学法、紫外分光光度法、色谱法、极谱法、电化学检测法等,其中,色谱法简单、灵敏,易于普及使用。  相似文献   
950.
National park plans are mainly prepared by a central planning team of the National Parks of Turkey. In this article, a model is presented that proposes a different approach to preparing national park plans. The study is based on a questionnaire distributed among the residents of the villages just outside a selected national park in Turkey and the relevant local and general authorities who are interested in the national park in their region, to find out the effect of public opinion on national park planning. Four basic strategies that represent the four main alternative approaches to forming policies in the planning of the park were identified. Respondents were asked to choose one and to suggest their own ideas. As this is a first attempt of such a study in Turkey, the results of the survey have been very encouraging. Therefore, this paper suggests that the assessment of public opinion should be borne in mind throughout the planning process in Turkey.  相似文献   
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