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31.
The particle and gas properties that profoundly affect design and performance of fly ash precipitators are discussed and evaluated in this section. Relation of the coal burned to these properties and to the precipitator gas cleaning problem is broadly examined. The need for a high order of technology consistently applied to cope successfully with the wide and often uncertain variations in coal and ash properties encountered in precipitation practices is emphasized.  相似文献   
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This article compares, contrasts and analyzes energy use data in five worldwide manufacturing subsectors. It documents the differences in energy input/production output ratios among industries and among countries, and outlines areas of opportunity for implementing energy conservation measures. Special attention is given to the energy use record in developing countries and to assessing their particular problems and limitations in reducing industrial energy demand.
Cet article établit des comparaisons, fait ressortir des contrastes et présente une analyse des données sur l'utilisation de l'énergie dans cinq sous-secteurs industriels mondiaux. Il explique les différences qui existent dans le taux de rendement relatif aux entrées-sorties dans les industries et les pays. Il désigne des secteurs où peuvent s'appliquer des mesures de conservation d'énergie. Une attention toute particulière est accordée aux tendances d'utilisation de l'énergie dans les pays en développement et à revaluation des problèmes et limitations qu'ils confrontent à réduire la demande d'énergie industrille.
Este artículo analiza comparativamente la información sobre uso de energía en cinco ramas industriales. Documenta los ratios insumo/producto en varios países e indica las oportunidades para establecer medidas para la conservacón de energa. Se da especial atención a los patrones de uso de energía en los países en desarrollo y evalúa los problemas particulares y limitaciones para la reducción del uso de energía en la indústria.  相似文献   
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This paper presents quantitative methods that allow scientists to compare the patterns in two maps that show a shared real variable. Specifically, this paper shows how to budget various components of agreement and disagreement between maps. The components are based on the separation of a map’s information of quantity from its information of location. The technique also examines how variation in resolution influences the measurement of the components of information. The manner in which the measurements change as a function of spatial resolution can be more important and interesting than the results at any single particular resolution, because the results at a single particular resolution may indicate more about the format of the data than about the overall pattern in the landscape. An example illustrates the mathematical concepts, and an application compares mapped vegetation indices in Africa to illustrate the usefulness of the proposed approach vis-à-vis a conventional approach. The results are presented visually in the form of stacked bar graphs that show separable components of information. The entire analysis is performed twice, each time with a different mathematical measurement of deviation: (1) root mean square error, and (2) mean absolute error. This paper compares these two approaches and discusses their relative advantages and disadvantages. Hopefully, this approach of budgeting components of information at multiple resolutions will become adopted as standard practice in the measurement of patterns.
Robert Gilmore Pontius JrEmail:
  相似文献   
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A divergence of values has become apparent in recent debates between conservationists who focus on ecosystem services that can improve human well‐being and those who focus on avoiding the extinction of species. These divergent points of view fall along a continuum from anthropocentric to biocentric values, but most conservationists are relatively closer to each other than to the ends of the spectrum. We have some concerns with both positions but emphasize that conservation for both people and all other species will be most effective if conservationists focus on articulating the values they all share, being respectful of divergent values, and collaborating on common interests. The conservation arena is large enough to accommodate many people and organizations whose diverse values lead them to different niches that can, with good will and foresight, be far more complementary than competitive. Los Nichos Complementarios de los Conservacionistas Antropocéntricos y Biocéntricos  相似文献   
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This paper examines the ‘range of choice’ concept in water management. Although many efforts have been made to design policies that broaden the consideration of water resources alternatives, the experiences gained from these policy experiments have not been adequately assessed. What insights might American policy approaches offer for developing countries? To address this question, four general policy types were identified and compared: (1) comprehensive single-objective policies; (2) comprehensive multiple-objective policies; (3) specific non-structural policies; and (4) specific technological policies. Case studies of each approach revealed that effective institutional development occurs when policies are: (1) stated in clear and specific language; (2) modified as experience is gained; (3) adequate in terms of statutory and administrative authority; and (4) subject to an orderly process of public and judicial review. The most successful policy efforts to date have involved specific alternatives, while multiple-objective policies have encountered the most difficulties. Common institutional problems are identified, and their potential relevance for developing countries is discussed.  相似文献   
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A survey of academic programs in air pollution control was made. Results from the 127 schools reporting are tabulated by state. Faculty involved in air pollution instruction are identified. Some conclusions and recommendations are presented.  相似文献   
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