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471.
This study attempts to assess the sources of occupational stress on air traffic controllers. It is based on data collected from a majority of air traffic controllers at a large U.K. airport. There are two unique methodological features described in this article. First, the use of the repertory grid technique as a method of generating work stressor variables, and second, the use of the multiple logistic equation as a coronary heart disease risk index.  相似文献   
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473.
ABSTRACT: The UN conference on Human Settlements (HABITAT) held in June 1976 at Vancouver, Canada, concluded that nearly two-thirds of the population of the developing world lacked access to safe drinking water and that a larger proportion lacked the means for hygienic human waste disposal. The conference urged governments to give priority to these two areas in their developement process. In March 1977, the UN Water Conference, held at Mar del Plata, Argentina, called for establishing the 1980's as the Decade for Drinking Water and Sanitation. The goal would be to bring clean water and sanitation to all peoples in the world by 1990. Since March 1979, four separate UN bodies have passed resolutions supporting the Decade and calling on all governments to support the Decade's goals. The U.S. Government, other OECD member states, and the private sector must combine to make this Decade a success.  相似文献   
474.
Conclusion Selections reported above were chosen as representative and reflective of the varieties of environmental education research currently reported in the literature. They were picked for this paper somewhat arbitrarily, from among more than 70 surviving an initial screening. No selection bias was intended, other than for the purpose of providing a representative variety. In most cases, abstracts printed in theCurrent Index to Journals in Education, Resources in Education, orDissertation Abstracts International were used in preparing these notes.These notes have been compiled by John F. Disinger, Professor of Environmental Education, School of Natural Resources, The Ohio State University, Columbus, Ohio 43210, USA; he is also Associate Director, Education Resources Information Centre (ERIC) Clearinghouse for Science, Mathematics, and Environmental Education (SMEAC). This contribution by Professor Disinger is in response to the editorial, Invitation to Promote Research Cooperation (The Environmentalist, 1 (3) 177–178.  相似文献   
475.
ABSTRACT: Two types of organizational systems provide most of the water service in the United States. The investor-owned firm operates on a profit basis generally subject to state commission regulation. The government-owned firm is generally confronted by local control. The comparative efficiency of private versus government firm provision of water services is essentially an empirical issue. Unit costs and other operating statistics are examined for water firms of each ownership form. The analysis shows that private firms tend to have higher operation costs than do government firms, possibly attributable to wage-salary differentials. The analysis also indicates that capital investment in large government firms may result in diseconomies. The analysis creates serious doubt as to whether efficient provision of water services can be better facilitated by large mergers of either ownership form.  相似文献   
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477.
Abstract: Opportunities for the development of an amalgam of park and leisure-oriented commercial establishments in urban-core waterfont settings exist in many U.S. cities. Public awareness of the need to enhance the environmental quality of these waterfont areas has resulted in a demand for planning and implementation action. However, the lack of understanding of urban political systems has been an inhibiting factor in the development of this park/ business concept. The major factors that influence the decision-making process leading to the development of urban-core waterfronts for park/business use are identified inthis paper. Understanding this decision-making process can aid project implementation and avoid waste of planning effort in time, dollars, and productivity.  相似文献   
478.
ABSTRACT: Gaged watersheds can provide information as to geomorphic, and geologic influence on the spatial variability of rainfall-runoff relationships. However, correlations between raingages distributed throughout the basin, and stream discharge are influenced by both storm patterns and drainage basin characteristics. Factor analysis has been applied to rainfall-runoff relationship to isolate the storm pattern from a basin response factor. Comparing two periods of time separated by eight years reveals relative stability in the rainfall attenuation (basin response) factor, while storm patterns for the two periods of record are quite disparate.  相似文献   
479.
The use of assimilation tools for satellite validation requires true estimates of the accuracy of the reference data. Since its inception, the Network for Detection of Stratospheric Change (NDSC) has provided systematic lidar measurements of ozone and temperature at several places around the world that are well adapted for satellite validations. Regular exercises have been organised to ensure the data quality at each individual site. These exercises can be separated into three categories: large scale intercomparisons using multiple instruments, including a mobile lidar; using satellite observations as a geographic transfer standards to compare measurements at different sites; and comparative investigations of the analysis software. NDSC is a research network, so each system has its own history, design, and analysis, and has participated differently in validation campaigns. There are still some technological differences that may explain different accuracies. However, the comparison campaigns performed over the last decade have always proved to be very helpful in improving the measurements. To date, more efforts have been devoted to characterising ozone measurements than to temperature observations. The synthesis of the published works shows that the network can potentially be considered as homogeneous within +/-2% between 20-35 km for ozone and +/-1 K between 35-60 km for temperature. Outside this altitude range, larger biases are reported and more efforts are required. In the lower stratosphere, Raman channels seem to improve comparisons but such capabilities were not systematically compared. At the top of the profiles, more investigations on analysis methodologies are still probably needed. SAGE II and GOMOS appear to be excellent tools for future ozone lidar validations but need to be better coordinated and take more advantage of assimilation tools. Also, temperature validations face major difficulties caused by atmospheric tides and therefore require intercomparisons with the mobile systems, at all sites.  相似文献   
480.
Abstract

The impact of weather on air pollution was examined and evaluated for the city of Athens, Greece. We used an objectively defined synoptic classification scheme consisting of six summer and eight winter circulation types. This scheme was established using a combination of both factor and cluster analysis during 1954–1999. Surface and isobaric levels of 850 hPa data were used. Factor analysis combined with cluster analysis was used to derive circulation types based on surface meteorological data for the period 1954–1999 in Athens and on surface pressure grid data. The city was divided into three sectors according to the financial and social activities of the residents. To examine the spatial characteristics of pollutant concentrations over Athens for each synoptic type, the synoptic circulation types were then correlated with both gaseous and particulate pollutant concentrations measured in each sector between 1983 and 1999. Finally, extreme and severe episodic events were studied in terms of their meteorological and synoptic characteristics.  相似文献   
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