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741.
ABSTRACT. The purpose of this paper is to present and discuss a procedure for finding an optimal staging plan for implementing a multi-basin water resource system-a system that must meet, with tolerable shortages, pre-specified but highly variable demands for water that increase over time-a system such as the proposed Texas Water System. The paper stresses that, in the past, planners have paid little attention to quantifying explicitly the impact that uncertainty has on the decision process, and in that context, presents a means for explicitly evaluating the impact that uncertainty has on finding and evaluating the performance of the optimal and several alternate staging plans. The procedure presented evaluates the impact that uncertainty, in both the hydrologic and the economic variables, has on the decisions that need to be made. The decisions requiring resolution are (1) which of an over-specified set of facilities should be constructed, (2) how large each of the facilities should be at various points in time, and (3) how should the system be operated so as to minimize the capital plus operational costs over the planning period. 相似文献
742.
C. W. Slaughter A. E. Helmers 《Journal of the American Water Resources Association》1974,10(2):256-264
ABSTRACT: It is increasingly recognized that natural resources research should in many cases be broadened in scope and oriented toward more general “environmental” problems. Locales with a history of “watershed” research can be eminently suited for development of comprehensive, environmental research programs. This is recognized in many research efforts of the International Biological Program (IBP), where watershed research sites have been successfully utilized for intensive investigations of process and function of selected ecosystems or ecosystem components. In the North American Subarctic there is almost no history of “watershed” studies. Basic data on hydrometeorologic parameters such as precipitation amounts and areal and seasonal distribution of runoff are scarce; the data framework within which environmental understanding can be structured is exceedingly sketchy. Opportunity exists in the discontinuous-permafrost settings of central Alaska to begin rectifying this situation. A basic program of multi-agency, multi-discipline research and data acquisition for the most significant hydrologic subregions is being developed, based around several existing environmental research areas (chiefly the Bonanza Creek Experimental Forest, the Caribou-Poker Creeks Research Watershed, the Wickersham Dome Fire Study Area, and a series of outlying sites). 相似文献
743.
Warren Viessman Karen E. Stork 《Journal of the American Water Resources Association》1974,10(3):440-446
ABSTRACT: A user-oriented research plan is presented herein. Its principal components are: (1) a mechanism for identifying social goals and translating them into research objectives; (2) procedures for setting priorities; (3) a program planning technique for designing projects to impact on important research objectives; (4) a mechanism for coordinating research activities of important research producers; (5) a structure for encouraging and establishing interdisciplinary team efforts when they are required; (6) a well-coordinated technology transfer plan; and (7) an effective method for promoting and sustaining user-researcher cooperation. Both basic and applied research designs are examined and criteria presented. The implementation of research plans is also discussed and various factors which play a role in implementation are outlined including: coordination, goal interpretation and priority setting, project Planning, Project review, interdisciplinary considerations and the user-researcher interface. 相似文献
744.
K. Jack Kooyoomjian Nicholas L. Clesceri 《Journal of the American Water Resources Association》1974,10(4):728-744
ABSTRACT: This paper examines four lake environments which are paired by lake size and by trophic state, where trophic state is employed as an identifier of water quality. Two large lakes and two intermediate-sized lakes, with each pair having one oligotrophic lake and one eutrophic lake are selected for cross-sectional survey-oriented questionnaire research. This paper focuses upon one aspect of the research, namely, the perception of water quality by three user groups. The user groups examined are recreationists, cottage and homeowners, and fishermen. The groups are compared utilizing percentage response profiles and cluster level groupings. It appears from a preliminary analysis of the data that the lakes selected are viable trophic state endpoints for questionnaire analysis of respondents. Each user group surveyed does appear sensitive to select water quality parameters; where shifts in sensitivity appear within and between user groups with changes in ecological settings, as well as with factors independent of ecological settings. 相似文献
745.
提出了电厂锅炉利用灰水进行除尘脱硫一体化的简易脱硫工艺,探讨了该工艺除尘和脱硫的原理,同时,对影响系统脱硫效率的因素进行了现场试验。试验表明,该系统脱硫效率较高,投资和运行费用低。 相似文献
746.
747.
通过对目前世界上规模最大的微污染水源水生物接触氧化处理工程运行过程中氨氮作效果的跟踪监测,较系统地对影响硝化处理效果的环境湿度、源水氨氮浓度、两类硝化细菌生长速率和转化能力的差异等因素进行了实验研究,为工程的运行参数控制提供了依据。 相似文献
748.
The Precautionary Principle: Scientific Uncertainty and Omitted Research in the Context of GMO Use and Release 总被引:3,自引:0,他引:3
Commercialization of genetically modified organisms (GMOs) have sparked profound controversies concerning adequate approaches to risk regulation. Scientific uncertainty and ambiguity, omitted research areas, and lack of basic knowledge crucial to risk assessmentshave become apparent. The objective of this article is to discuss the policy and practical implementation of the Precautionary Principle. A major conclusion is that the void in scientific understanding concerning risks posed by secondary effects and the complexity ofcause-effect relations warrant further research. Initiatives to approach the acceptance or rejection of a number of risk-associated hypotheses is badly needed. Further, since scientific advice plays a key role in GMOregulations, scientists have a responsibility to address and communicate uncertainty to policy makers and the public. Hence, the acceptance of uncertainty is not only a scientific issue, but is related to public policy and involves an ethical dimension. 相似文献
749.
750.
Third World countries should exploit the genetic information stored in their flora and fauna to develop independent and highly competitive biotechnological and pharmaceutical industries. The necessary condition for this policy to succeed is the reshaping of their universities and hospitals—to turn them into high-caliber research institutions dedicated to the creation of original knowledge and biomedical invention. Part of the service of the Third World foreign debt should be co-invested with the lending banks in high technology enterprises. This should be complemented with an active program of investments in First World biotech companies and university research departments which could contribute to the solving of problems connected with the First World. These strategic alliances would allow effective training of molecular biologists, improvement of South American universities, and education of biotechnologists, managers, and lawyers in the complexities of high-technology business. The establishment of real joint ventures between developed and underdeveloped countries might contribute to change the present strained relations between the North and the South, and science and technology could become real forces of social and economic development. 相似文献