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961.
962.
M. Gueri E.S. Guerra L.E. Gonzalez N.A. Martinez A.V. Olivares E. Rosero C. de Ville de Goyet 《Disasters》1983,7(3):174-179
A retrospective study of the effects of the Tumaco earthquake of 1979 shows a smaller number of deaths and injuries than in earthquakes of similar magnitude that have occurred elsewhere, which is probably related to the type of building. Most of the deaths were caused by a tsunami. Proportionally the mortality was higher in the 0 to 4 age group. Among the injured, most of the lesions were minor. Morbidity was higher in the over 45 years age group, and lower among the "under-fives." There was an evident need for a simple "disaster medical record card." Coordination among the different relief agencies could have been better. 相似文献
963.
This paper investigates the scope for stabilizing commodity prices by buffer stock interventions. Optimal control is used, rather than simulation, to evaluate the scope for intervention at best. Applications to a world copper market model show that substantial but extensive gains to stabilization are possible. These gains cannot be realised by traditional bandwidth decision rules. An important difficulty is setting the level at which prices should be stabilized. The lack of this information severely reduces the achievable gains. 相似文献
964.
The thelycum morphology of 7 species of the genus Nematoscelis, based upon observations with the scanning electron microscope, is described. The thelycum of N. megalops and N. difficilis did not differ either with respect to general morphology of the thelycum, or in spermatophore insertion. In the other 5 species, N. tenella, N. gracilis, N. atlantica, N. lobata, N. microps, the main thelycum structure consists of a central lobe of various forms, to which a filamentous spermatic mass is attached. Preliminary observations on the position of the genital pores of two species are reported briefly. 相似文献
965.
This review describes the more important features of the emission, chemistry, transport and deposition of pollutants involved in acid deposition. Global emissions, both natural and man-made, of sulphur and nitrogen oxides are discussed and examples of spatial distributions and trends over the last century presented. The more significant chemical and physical processes involved in the transformation of the primary emissions into their acidic end products are described, including a summary of the approximate timescales of the processes involved. Measurements and modelled calculations of spatial and temporal patterns in the deposition of acidic pollutants by both wet and dry pathways are presented. 相似文献
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970.
Albin Brandstetter Roger L. Engel Dennis B. Cearlock 《Journal of the American Water Resources Association》1973,9(6):1188-1200
ABSTRACT: A comprehensive mathematical model (Urban Wastewater Management Model) has been developed to continuously simulate time-varying wastewater flows and qualities in complex metropolitan combined sewerage systems. The model serves three functions: (1) assessment of existing or planned system performance in relation to other wastewater discharges in either a metropolitan or river basin area; (2) determination of the optium operation or automatic control of existing or planned systems during rainstorms; and (3) determination of the most economically feasible combination of design alternatives for improving or expanding existing systems to meet specified performance criteria. The model provides an efficient engineering tool for evaluating and controlling pollutant discharges from combined sewerage systems (including treatment plants) to receiving waters, while considering the time and spacial variations of rainfall and dry-weather flows and qualities as well as economic constraints. 相似文献