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991.
建筑施工伤亡事故现状、原因及其对策 总被引:1,自引:1,他引:1
刘少华 《中国安全科学学报》1996,6(4):58-61,57
应用安全系统工程学原理及方法分析建筑行业伤亡事故增多的根本原因;综合阐述建筑安全的基本对策,以求标本兼治,使建筑施工伤亡严峻形势得到根本好转 相似文献
992.
S. B. Kendie 《Environmental management》1996,20(1):1-10
In the examination of the implementation of rural drinking water facilities, not enough attention has been paid to analyzing
the socioeconomic and political relationships that affect the effective utilization of the facilities, particularly as these
relate to women in rural society. This paper suggests that much of the difficulty in instituting the utilization of safe water
supply sources has to do with the rather low economic status of women—the main water collectors. Poverty consigns women to
long periods of work in activities or jobs that bring little reward. This makes it difficult to effectively digest the messages
delivered by program staff and limits the extent of usage of the safe water facilities. 相似文献
993.
Robert M. Kahn Bruce D. Smith Austin Long 《Journal of the American Water Resources Association》1996,32(3):629-635
ABSTRACT: A study of 222Rn concentrations in the water distribution system of Tucson, Arizona, revealed levels of 60 to 1260 pCi/L in domestic waters. These measurements are comparable to levels of between 80 and 1400 pCi/l for 222Rn found in ground water samples in the North-Central Tucson basin (Kahn et al., 1994). Estimated loss of 222Rn due to radioactive decay during travel from the well head to the home ranges from 8 to 50 percent. 相似文献
994.
Seema Bathla 《Environment, Development and Sustainability》1999,1(2):105-121
The paper examines the linkages between water depletion, continuous population growth and economic development viewed primarily as agricultural development. This is done within a framework of a dynamic simulation model of ecological-economic type over extended periods of time. It is found that intensive agriculture, driven by an increase in the cropping intensity as a result of increase in area under paddy crop, has led to an increased gap between the demand for and supply of water resources, in particular subsurface resources. The consequent fall in water table may lead to constraints in the use of water. This has strong inequity implications in the resource use as well as threats to future of agricultural development in the region. It is revealed that a mix of interventions based on price solutions, non-price solutions and institutional set up are decisive in bringing a sustainable development and use of resource. The paper concludes with emphasising the role of state/government in achieving the desired goal. 相似文献
995.
James W. McFarland M. Leon Hyatt 《Journal of the American Water Resources Association》1973,9(4):755-767
Alternative futures are defined to be mutually consistent alternative combinations of assumed sets of future conditions. Alternative futures are employed in conjunction with the Wollman-Bonem model to project future water use. The model solutions under different alternative futures provide an indication of the direction and relative magnitude of changes in water use, both in quantity and quality, that may result from changes in policy-influenced variables, technology, and other data. The Wollman-Bonem model is employed in this paper as a tool to illustrate the alternative futures concept. The model can best be cast as an economic model. The model solutions are not given as a set of formal projections, but as various possible water-use-over-time curves. This should aid in disspelling the erroneous idea that it is possible to make distant projections of water use as a single curve. Multiple curves suggest that water use is really a function of many variables. 相似文献
996.
Charles W. Mallory John J. Boland 《Journal of the American Water Resources Association》1970,6(6):980-989
A system study was conducted on the use of a large number of small reservoirs dispersed throughout an urban community as a means of storm water pollution control. The study was based on an area within the “new city” of Columbia, Maryland. Water collected and stored in the reservoirs is treated for release or use in meeting sub-potable and potable water demands in the community. Design and performance criteria were developed for such a system. A simulation model and a computerized evaluation technique were used to select the optimal locations and system configurations. The results of this study indicated that such a system would be less expensive than a conventional engineering approach to storm water pollution control. Further, the benefits derived from use of the storm water as a water supply can offset a portion of the cost of pollution control. Several secondary benefits also result from this concept including erosion and sediment control, storm flow dampening, and recreational facilities. A program is now underway to demonstrate this concept in Columbia, Maryland. 相似文献
997.
ABSTRACT: Temporary transfers of water for dry year water supply are analyzed for cost and operational feasibility. The temporary transfer is implemented as part of a water rights option agreement (WROA) between a lesson and a lessee. First, engineering analysis determines the technical feasibility and operations plan under the Colorado doctrine of prior appropriation. The cost of the WROA to a water utility is estimated. Other considerations in the agreement are discussed. The WROA is compared to other dry-year supply alternatives using a water system simulation model to obtain expected cost and operational performance characteristics. 相似文献
998.
O. C. Grunewald C. T. Haan David L. Debertin D. I. Carey 《Journal of the American Water Resources Association》1976,12(5):951-962
ABSTRACT: This study proposes that demand management through pricing policies can be used in conjunction with supply management to solve water supply problems. Economic principles are shown to apply to rural residential water use. A demand function for water was developed based on cross-sectional water use data collected in Kentucky. Price was found to be a significant determinant of the quantity of water demanded. A constant price elasticity of -0.92 was found. The demand function was used in a simulation analysis to determine reservoir capacity needed to supply water needs of a rural community. The simulation revealed that price can significantly affect required reservoir storage. 相似文献
999.
Robert Willis Donald R. Anderson John A. Dracup 《Journal of the American Water Resources Association》1976,12(1):157-174
ABSTRACT. A general planning model for simulation of water quality in streams and canals is formulated and verified. The model simulates the temporal and spatial variations in conservative and nonconservative constituents. The nitrogen cycle and its interaction with other nutrients and the dissolved oxygen resources of the stream are included. A fully implicit finite difference approximation is used to solve the mass transport equations describing variations in constituent concentrations throughout the stream systems. The model is applied to the Truckee River in northern California. Results indicate the applicability of the model for assessing the impact of alternative water quality management strategies on the stream system. 相似文献
1000.
William Whipple 《Journal of the American Water Resources Association》1981,17(5):814-819
Water conservation is a much emphasized policy of the Federal government. Discussion of water conservation proposals often involves confusion between a conservation “ethic,” which is an end in itself, and conservation as a means for attaining various economic objectives. Analysis indicates that outside of ground water “mining.” water is usually a renewable and reusable resource. During periods of normal precipitation, water conservation should be employed only when the value of the water saved exceeds the cost of effecting the savings. Water conservation is most valuable as a drought contingency tactic. Water conservation as a substitute for structural provision to meet normal water demand growth is apt to prove shortsighted. 相似文献