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271.
Effective planning of resources management is important for facilitating socio-economic development and eco-environmental sustainability. Such a planning effort is complicated with a variety of uncertain, dynamic and nonlinear factors as well as their interactions. In this study, an inexact-stochastic quadratic programming with recourse (ISQP-R) method is developed for reflecting dynamics of system uncertainties based on a complete set of scenarios as well as tackling nonlinearities in the objective function to reflect the effects of marginal utility on system benefits and costs. Moreover, since penalties are exercised with recourse against any infeasibility, the ISQP-R can support the analysis of various policy scenarios that are associated with different levels of economic consequences when the promised targets are violated. The developed method is applied to a case study of planning resources management and developing regional ecological sustainability. The results have been generated and are helpful for decision makers in not only identifying desired resources-allocation strategies but also gaining insight into the tradeoff between economic objective and eco-environment violation risk. 相似文献
272.
通过筛选实验,从土壤中新分离到1株对活性艳红K-2BP具有明显脱色效果的酵母菌株Y-G-1,经鉴定为克鲁斯假丝酵母Candida krusei.该菌株对含活性艳红K-2BP起始浓度为200mg/L的培养基,最大脱色率为99%,达到最大脱色率的时间是12h.克鲁斯假丝酵母的最佳接种量应不低于5%(体积分数),培养基最适pH在4~9之间,氮源(NH4)2SO4浓度不低于0.1%,相对应的碳源葡萄糖浓度不低于0.5%.对脱色机理的研究表明,该菌株对活性艳红K-2BP的去除属于降解脱色.此外,该菌株对另外9种染料(50mg/L)的脱色率在62%~96%之间.其中,对偶氮染料弱酸艳红B、活性黑KN-B和活性红M-3BE的脱色率都达到了90%以上,对三苯甲烷染料(酸性媒介漂蓝B)的脱色率达到了93%.表明克鲁斯假丝酵母在染料废水的处理上可能具有较好地应用潜能. 相似文献
273.
Weather, climate, and flood predictions are incorporated into human decisions in a wide variety of situations, including decisions related to hazardous hydrometeorological events. This article examines ethical aspects of such predictions and decisions, focusing on the case of the 1997 Red River flood in Grand Forks, North Dakota and East Grand Forks, Minnesota (US). The analysis employs a formal ethical framework and analytical method derived from medical and business ethics. The results of the analysis highlight issues related to forecast generation, communication of forecast meaning and uncertainty, responsibility for the use of forecasts in decision making, and trade-offs between the desire for forecast certainty and the risk of missed events. Implications of the analysis for the broader arenas of weather, climate, and flood prediction and disaster management are also discussed. 相似文献
274.
The results of a discrete choice experiment (DCE) as a part of a survey among the urban riverbank residents on the Red River in Winnipeg, Manitoba, Canada, indicated that the risk of over-dike flooding, set at 2 ft above the 1997 flood water level, was a significant determinant of both voluntary and mandatory evacuation, compared to those set at the 1996 or 1997 levels. Mandatory evacuation was more preferred over voluntary evacuation when the likelihood of flooding was at its most severe, and the opposite relationship was the case when the likelihood was low. The notification time for evacuation, suggested as 1, 2, and 4 days, proved to be an insignificant attribute, whereas the respondents indicated significant preference for full flood compensation over an offer of either 80% or 90% flood relief, irrespective of the alternatives of voluntary or mandatory evacuation. 相似文献
275.
Samples of Mugil cephalus, Liza ramada, Siganus luridus, Siganus rivulatus, Epinephelus alexandrinus, Epinephelus areolatus, Epinephelus fasciatus, Epinephelus chlorostigma, Cephalopholis argus and Cephalopholis sonnerati were collected from the Mediterranean and Red Seas and their muscle and bone analyzed by AAS for some trace metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Pb). the results showed that these metals accumulate in the bones to a greater extent than in the muscle. the highest accumulated element is cobalt (4.7-20.8 times), while the lowest is lead (1.1-2.5 times). the accumulation is more pronounced in Red Sea species than in Mediterranean species. the elevated levels of lead in Mugil cephalus (2.6-3.0 mg kg-1) and Epinephelus alexandrinus (3.0-3.9 mg kg-1) were attributed to the intake in food in the polluted environment of Alexandria coastal water. the relationship between body size and concentration of trace metals using a standard linear regression technique gives a significant positive correlation for cobalt, manganese, iron and lead in the muscle, as well as for lead in the bones of Mugil species from the Red Sea, while the Mediterranean species showed little correlation.
There is a tendency for increased concentrations of the essential metals manganese, iron and copper with increasing trophic level of the fish, while the opposite is true for the toxic metals chromium and lead. Our results indicate that there is no risk from toxic metal concentrations in muscle of fish from the Mediterranean and Red Seas consumed by man even in contaminated areas. 相似文献
There is a tendency for increased concentrations of the essential metals manganese, iron and copper with increasing trophic level of the fish, while the opposite is true for the toxic metals chromium and lead. Our results indicate that there is no risk from toxic metal concentrations in muscle of fish from the Mediterranean and Red Seas consumed by man even in contaminated areas. 相似文献
276.
Siar SV 《Environmental management》2003,31(5):0569-0580
The coastal zone is a place of intense activity where resources, users, and resource-use practices interact. This case study
of small-scale fisheries in Honda Bay, Palawan, Philippines shows that resources, space, and gender are intertwined. The study
was conducted between June 1997 and July 1998. The data were gathered using free listing, pile sort, ranking, resource mapping,
and key informant interviews. The results showed that women's knowledge about fishery resources and their fishing activities
are associated with the intertidal zone whereas men's knowledge is associated with coral reefs. In classifying fishery resources,
appearance is the main consideration for women whereas a combination of appearance, habitat, and type of fishing gear is the
consideration used by men. Market price is very important because of its dependence on the demand of the export market as
well as the local market. Women dominate the buying of fishery products. Many women market their husband's catch, process
fish, or gather shells and sea cucumber for sale. Among the fishing households, type of fishing gear provides an indication
of socioeconomic standing. This paper concludes that access to resources is shaped by gender and age. The differences in resource
knowledge possessed by men and women lead to differential access to fishery resources. In addition, the differences in socioeconomic
status also influence resource access. The socialization of children into fishing reinforces the gender division of labor
and space in the coastal zone. 相似文献
277.
PROBLEM: This paper evaluates the stopping propensity of drivers at matured in-service red light camera (RLC) signalized T-intersections after a number of years of camera operation. METHOD: A special-purpose data logger working in conjunction with loop sensors was used to gather traffic parameters, vehicle stopping/crossing movements, and signal phases at camera (treatment) and noncamera (comparison) approaches. Logistic modeling was employed to determine the stopping/crossing decisions of civilian vehicle drivers in response to the onset of yellow (amber) with traffic and the associated situational and behavioral variables, including their interactions. SUMMARY: The propensity to stop at camera approaches was about 17 times more than at noncamera approaches. This finding strongly affirmed the positive effect of RLC in encouraging drivers to stop. The likelihood to stop was about 6.5 times higher for an approach that faces an opposing right-turn conflict immediately after the onset of red. Higher stopping propensity was also more prevalent during weekdays and in periods of low traffic volumes. IMPACT ON INDUSTRY: The findings provided an objective measure on the effectiveness of RLC that would be useful to evaluate intersections for camera installation as well as on the implementation and operational aspects of RLC program. 相似文献
278.
DeVerle P. Harris 《Resources Policy》1984,10(2):81-100
Political-economic events of the 1970s brought mineral resource appraisal to the focus of national policy. Estimates of and methodologies for mineral resources appraisal were scrutinized, revealing deficiencies in method and data and fostering considerable debate about the credibility of estimates and about preferred methodology. Since credibility can be increased through the acquisition of additional geoscience information, questions regarding methodology have more than one formulation and therefore more than one correct solution, depending upon the expected value of additional information and the conditional losses of relevant policy options. When existing information is meagre and the expected value of information is high, the optimum decision may be to defer all policy options until after the acquisition and analysis of- additional information. Decision theory offers an analytical framework that is sufficiently generalized to provide answers for highly varied circumstances of geoscience and resource information and policy issues. Our ability to perform any such analysis is limited by inaccuracies in both geologists' estimates of undiscovered mineral resources, and in economists' calculations of conditional losses of policy options for each of the relevant states of mineral resources. 相似文献
279.
John J. Knightly Reece Morehead 《Journal of the American Water Resources Association》1979,15(5):1221-1225
ABSTRACT: The Water Resources Scientific Information Center (WRSIC) provides comprehensive indexing/abstracting for the water resources literature. To determine in one objective way the coverage of this information service from a user's point of view, an extensive sampling of the journal literature was used to determine extent to which 10 leading water resources journals are indexed and abstracted by the system. Coverage is so high that some users will want to change toward greater use of the system. 相似文献
280.