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The Science of Nature -  相似文献   
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Walter LS 《Disasters》1990,14(1):20-35
Various kinds of Satellites, including communications, meteorology, remote sensing and geophysics satellites, are, or may become, useful tools in disaster prevention, preparedness and relief. They already provide operational capability for storm warnings and search-and-rescue efforts. Other capabilities, such as improved flood prediction and global mobile communications during relief, are close within reach. Still others, such as earthquake prediction, require considerable research. Close cooperation and communication between space technologists and disaster-management specialists will be needed in guiding research and designing and testing satellite systems. It is hoped that the International Decade for Natural Disaster Reduction can provide a framework for such activities.  相似文献   
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Behavioral ecologists generally agree that animals derive benefits from familiarity with spaces that they inhabit or visit, yet site familiarity is rudimentary or lacking in most models of habitat selection. In this review, I examine evidence for the occurrence of site familiarity and its fitness benefits, describe the difficulty of measuring site familiarity, note its omission from the influential ideal free and ideal despotic models, and use a literature search to test an assumption of the ideal models that has become widespread in habitat selection theory: that animals behave without regard for site familiarity. I find little support for such “familiarity blindness” in vertebrates. Next I discuss how the study of public information has drawn attention away from site familiarity and point out that both kinds of information are likely to be important in habitat selection. I proceed to examine current models of initial settlement (exploration and settlement of prebreeders on first territories) and optional resettlement (site fidelity or dispersal by established breeders following a period of prospecting) and find that the latter include only basic forms of site familiarity. Hence, I develop the concept that an inhabited space holds a unique “private value” to an animal based on its familiarity with the space and offer a simple model for optional resettlement based on private value that generates several novel predictions, including site fidelity based on cumulative breeding site familiarity and high site fidelity among species with complex territories.  相似文献   
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Sampling for nitrogen and sulfur dioxides was initiated at several National Air Sampling Network stations in 1959 using a sampler developed for that purpose. In 1961 the Gas Sampling Network was expanded to its maximum of 49 stations. Sampling equipment and collecting solutions are supplied and chemical analyses performed by the network laboratories. Sampling and analysis procedures are described briefly. Average and maximum 24-hour concentrations of nitrogen dioxide and sulfur dioxide observed at 48 stations during 1961-1963 are presented.  相似文献   
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