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221.
从造纸中段废水絮凝法处理和生化处理效果的实验研究结果出发,讨论了造纸中段废水处理的技术路线,指出絮凝法与好氧生化法联用是该废水处理的适宜方法。根据废纸造纸产生的两股废水(打浆洗涤废水和抄纸废水)的污染物特性,提出了废纸造纸废水处理的5条设计原则。  相似文献   
222.
ABSTRACT: The primary objective of this study was to perform a cost‐benefit analysis of maintaining the current level of water quality in the Catawba River basin. Economic benefits were estimated using a stated preference survey method designed to value respondents' willingness to pay for a management plan to protect water quality in the Catawba basin over time. From the surveys conducted with 1,085 area residents, we calculated an annual mean willingness to pay of $139 for the management plan, or more than $75.4 million for all taxpayers in the area. Over the five‐year time horizon in which respondents were asked to pay for the management plan, this resulted in a total economic benefit of $340.1 million. The Watershed Analysis Risk Management Framework model was used to estimate the amount of management activities needed to protect the current level of water quality in the basin over time. Based on the model results, the total cost of the management plan was calculated to be $244.8 million over a ten‐year period. The resulting cost‐benefit analysis indicated that the potential benefits of this management plan would outweigh the costs by more than $95 million.  相似文献   
223.
Amphibians are severely affected by climate change, particularly in regions where droughts prevail and water availability is scarce. The extirpation of amphibians triggers cascading effects that disrupt the trophic structure of food webs and ecosystems. Dedicated assessments of the spatial adaptive potential of amphibian species under climate change are, therefore, essential to provide guidelines for their effective conservation. I used predictions about the location of suitable climates for 27 amphibian species in the Iberian Peninsula from a baseline period to 2080 to typify shifting species’ ranges. The time at which these range types are expected to be functionally important for the adaptation of a species was used to identify full or partial refugia; areas most likely to be the home of populations moving into new climatically suitable grounds; areas most likely to receive populations after climate adaptive dispersal; and climatically unsuitable areas near suitable areas. I implemented an area prioritization protocol for each species to obtain a cohesive set of areas that would provide maximum adaptability and where management interventions should be prioritized. A connectivity assessment pinpointed where facilitative strategies would be most effective. Each of the 27 species had distinct spatial requirements but, common to all species, a bottleneck effect was predicted by 2050 because source areas for subsequent dispersal were small in extent. Three species emerged as difficult to maintain up to 2080. The Iberian northwest was predicted to capture adaptive range for most species. My study offers analytical guidelines for managers and decision makers to undertake systematic assessments on where and when to intervene to maximize the persistence of amphibian species and the functionality of the ecosystems that depend on them.  相似文献   
224.
Conservation practitioners, natural resource managers, and environmental stewards often seek out scientific contributions to inform decision-making. This body of science only becomes actionable when motivated by decision makers considering alternative courses of action. Many in the science community equate addressing stakeholder science needs with delivering actionable science. However, not all efforts to address science needs deliver actionable science, suggesting that the synonymous use of these two constructs (delivering actionable science and addressing science needs) is not trivial. This can be the case when such needs are conveyed by people who neglect decision makers responsible for articulating a priority management concern and for specifying how the anticipated scientific information will aid the decision-making process. We argue that the actors responsible for articulating these science needs and the process used to identify them are decisive factors in the ability to deliver actionable science, stressing the importance of examining the provenance and the determination of science needs. Guided by a desire to enhance communication and cross-literacy between scientists and decision makers, we identified categories of actors who may inappropriately declare science needs (e.g., applied scientists with and without regulatory affiliation, external influencers, reluctant decision makers, agents in place of decision makers, and boundary organization representatives). We also emphasize the importance of, and general approach to, undertaking needs assessments or gap analyses as a means to identify priority science needs. We conclude that basic stipulations to legitimize actionable science, such as the declaration of decisions of interest that motivate science needs and using a robust process to identify priority information gaps, are not always satisfied and require verification. To alleviate these shortcomings, we formulated practical suggestions for consideration by applied scientists, decision makers, research funding entities, and boundary organizations to help foster conditions that lead to science output being truly actionable.  相似文献   
225.
ISAPEC中知识自动获取的设计与实现   总被引:1,自引:0,他引:1  
剖析了利用人工神经网络实现大气污染总量控制规划智能决策支持系统(ISAPEC)中知识自动获取的必要性,论述了ISAPEC中知识的自动获取的设计与实现过程,并用一实例进行了验证。结果表明用人工神经网络实现知识的自动获取与知识的人工获取相比既具有更高的时间效率,又能保证更高的质量。  相似文献   
226.
227.
传统的基于GIS建立的土地适宜性评价系统缺乏对空间问题决策的支持能力,而GIS与DSS技术集成建立土地适宜性评价决策系统一方面可以实现对空间数据的管理和分析,另一方面可以利用模型进行辅助决策,有利于解决与空间有关的决策问题。以MapInfo Professional 6.0为基础平台,以Visual 〖XC夏敏字1.TIF,JZ〗6.0为开发工具,建立了一个土地适宜性评价决策支持系统,该系统包括数据库系统、模型库系统、知识库系统以及人机接口4个部分,具有数据输入输出、图属互查、数据空间分析和辅助决策等功能。系统成功应用于南京市江宁区淳化镇农地适宜性评价实践中,应用结果表明系统能为决策者提供多种决策方案,同时又集成了GIS的数据管理和空间分析功能,满足土地适宜性评价的要求,有推广使用的价值。  相似文献   
228.
本文简要地介绍了QSDWZHYC—1智能辅助决策系统结构、功能以及所采用的技术途径。应用QSDWZHYC—1系统可预测企事业单位现有房屋的震害,评估经济损失和人员伤亡,优化抗震加固方案,识别高危害房屋类别,找出单位建(构)筑物地震危害的薄弱环节。为企事业单位抗震减灾对策进行辅助决策。  相似文献   
229.
This paper seeks to understand evacuation behaviour in a case of spontaneous evacuation. During the Second Lebanon War of 2006, more than one‐third of residents in north Israel spontaneously evacuated—the remainder stayed in situ. Using a telephone survey of 665 respondents residing in north Israel, we were able to characterise the behaviour of evacuees and non‐evacuees. The main reasons cited for evacuating were fear of injury to self or family, the effect on children, inability to remain in a protective space, and family pressure. The main reasons cited for remaining at home were no suitable alternative, did not perceive a high level of danger, had to go to work, and there is no place like home. There were no significant differences with regard to most socio‐demographic characteristics of the population. These findings should aid emergency managers in preparing the population for a future emergency and in engaging in effective dialogue with the population during an emergency on the evacuation option.  相似文献   
230.
近年来,由于生产的全球化、工业水平的迅速提高、技术系统的复杂化和规模化,以及社会结构急剧变化,我国技术灾害的发生频次增多,强度加剧,经济损失趋于上升.技术灾害继自然灾害之后,已逐渐发展为威胁我国人民生命安全和生存环境的主要灾种.基于技术灾害数据库,从致灾因子多度、风险频数、相对损失强度和综合风险指数等4个方面对中国技术灾害的时序变化和区域差异进行了分析与探讨,以期加深对中国技术灾害的系统认识,并为中国技术灾害的风险管理提供依据.  相似文献   
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