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61.
Ronald M. North 《Natural resources forum》1993,17(3):216-227
Over the past 30 years, we have seen the birth and growth of multiple objective analysis from an idea without tools to one with useful applications. Models have been developed and applications have been researched to address the multiple purposes and objectives inherent in the development and management of water resources. A practical approach to multiple objective modelling incorporates macroeconomic-based policies and expectations in order to optimize the results from both engineering (structural) and management (non-structural) alternatives, while taking into account the economic and environmental trade-offs. 相似文献
62.
Walter P. Neely Ronald M. North James C. Fortson 《Journal of the American Water Resources Association》1976,12(1):19-25
ABSTRACT. A multiple goal planning approach is proposed as a solution to the public water resources project selection problem. The goal programming technique enables a comprehensive water resources model. The model considers both economic and environmental objectives and may be implemented with data which are available to project planners. 相似文献
63.
综述了非调质钢的工艺性能和力学性能及在汽车上的应用.说明非调质钢具有切削加工性能良好,可实施焊接和表面处理;节约能源、简化生产工序、大幅度降低成本等优点. 相似文献
64.
Land use change and carbon exchange in the tropics: I. Detailed estimates for Costa Rica,Panama, Peru,and Bolivia 总被引:1,自引:0,他引:1
Charles A. S. Hall R. P. Detwiler Philip Bogdonoff Sheila Underhill 《Environmental management》1985,9(4):313-333
Our group, composed of modelers working in conjunction with tropical ecologists, 3 has produced a simulation model that quantifies the net carbon exchange between tropical vegetation and the atmosphere due to land use change. The model calculates this net exchange by combining estimates of land use change with several estimates of the carbon stored in tropical vegetation and general assumptions about the fate of cleared vegetation. In this report, we use estimates of land use and carbon storage organized into sixlife zone (sensu Holdridge) categories to calculate the exchange between the atmosphere and the vegetation of four tropical countries. Our analyses of these countries indicate that this life zone approach has several advantages because (a) the carbon content of vegetation varies significantly among life zones, (b) much of the land use change occurs in life zones of only moderate carbon storage, and (c) the fate of cleared vegetation varies among life zones. Our analyses also emphasize the importance of distinguishing between temporary and permanent land use change, as the recovery of vegetation on abandoned areas decreases the net release of carbon due to clearing. We include sensitivity analysis of those factors that we found to be important but are difficult to quantify at present. 相似文献
65.
Gerald K. Moore Gary W. North 《Journal of the American Water Resources Association》1974,10(5):1082-1096
ABSTRACT: Panchromatic black and white, color, and color infrared photographs and thermal infrared imagery are compared for a capability to show flood boundaries. In open agricultural and urban areas, these boundaries are easily delineated on all types of am. Boundaries are more difficult to see in wooded areas. In March, hardwood trees are dormant, but black and white photographs and color photographs show only the tops of these trees. Color infrared photographs in January and March have a distinctive color or tone in inundated woods; the limit of this tone is the flood boundary. Daytime thermal infrared imagery in March shows that inundated woods are cooler than dry land but warmer than open water. After about April 1, both color infrared photography and thermal infrared imagery show only the top of the tree canopy and do not reflect underlying flood water. Inundated areas can be delineated easily on ERTS satellite imagery from December through March. On imagery from May 4–5, 1973, however, most inundation boundaries had to be drawn as dashed lines; the tree canopy obscures flood waters in wooded areas. Despite this problem, the results of mapping flood boundaries on May imagery are believed to be reasonable for the scale of the imagery. 相似文献
66.
Philip A. R. Maxwell Ronald M. North 《Journal of the American Water Resources Association》1974,10(6):1277-1287
ABSTRACT: An analogue method of ex post evaluation is proposed as a method of measuring the effectiveness of small watershed projects in obtaining flood control and economic benefits. Two watersheds were compared on a “with vs. without” project basis by both direct and indirect measurement of economic benefits. Direct measurements indicated that small watershed flood control projects did not generate the expected economic benefits. However, the indirect measurements of the same watersheds using land value enhancement as a surrogate suggested that the expected economic benefits were reflected in differential land values. The economic efficiency of small watershed projects should be measured ex ante and ex post on a “with vs. without” project basis rather than on a “before vs. after” basis whether using direct or surrogate variables. 相似文献
67.
68.
Jackie Sellers Ronald M. North 《Journal of the American Water Resources Association》1979,15(1):189-197
ABSTRACT: In this article a managerial approach to developing and implementing National Water Resources policy is suggested. Proper consideration can be given to national economic development (NED), environmental quality (EQ) and conservation and still result in an implementable policy at the operational level if proper incentives are built into the process with proper attention to alternate non-Federal cost sharing rates. Not only can these multiple objectives be entertained but the Administration and Congress will have a management tool that should ensure a certain probability of success. 相似文献
69.
70.