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441.
Fontaine JJ 《Journal of environmental management》2011,92(5):1403-1408
The loss of biodiversity is a mounting concern, but despite numerous attempts there are few large scale conservation efforts that have proven successful in reversing current declines. Given the challenge of biodiversity conservation, there is a need to develop strategic conservation plans that address species declines even with the inherent uncertainty in managing multiple species in complex environments. In 2002, the State Wildlife Grant program was initiated to fulfill this need, and while not explicitly outlined by Congress follows the fundamental premise of adaptive management, 'Learning by doing'. When action is necessary, but basic biological information and an understanding of appropriate management strategies are lacking, adaptive management enables managers to be proactive in spite of uncertainty. However, regardless of the strengths of adaptive management, the development of an effective adaptive management framework is challenging. In a review of 53 State Wildlife Action Plans, I found a keen awareness by planners that adaptive management was an effective method for addressing biodiversity conservation, but the development and incorporation of explicit adaptive management approaches within each plan remained elusive. Only ~25% of the plans included a framework for how adaptive management would be implemented at the project level within their state. There was, however, considerable support across plans for further development and implementation of adaptive management. By furthering the incorporation of adaptive management principles in conservation plans and explicitly outlining the decision making process, states will be poised to meet the pending challenges to biodiversity conservation. 相似文献
442.
基于D-S理论的企业安全绩效综合评定研究 总被引:1,自引:0,他引:1
为客观评定企业安全绩效,提出一种基于D-S证据理论的企业安全绩效综合评定方法。在确定安全绩效评定指标的基础上,利用模糊函数和群决策方法处理评价过程中的不确定信息,将多源决策信息转换为同一框架下的评价信息,然后根据各决策信息的重要度,通过D-S证据理论的mass函数和证据合成方法对安全绩效评价群决策中的不确定性信息逐层融合。实例表明,该方法能够克服D-S冲突问题,保证企业安全绩效综合评定信息融合结果的准确度,企业安全管理的优劣势的表征更为直观。 相似文献
443.
基于熵权的区间型多属性决策方法在湖泊水质评价中的应用 总被引:4,自引:2,他引:2
针对现有多属性决策方法在水质评价过程中忽视指标在某一等级内效用相同,导致指标间过度补偿,综合评价效果失真的问题,本文考虑将指标时序或空间的多个监测值转化成区间数以降低数据维度,保留时序信息,同时通过定义指标区间到约定等级区间的距离,体现评价强调达标的特点,进而利用熵权法从指标平均水平达标的一致性和变化幅度的趋同性两方面筛选评价作用显著的指标.该方法在指标测度阶段和指标生成阶段压缩决策矩阵维度,简化了评价过程的计算.最后通过对太湖水域的水质数据的评价案例说明了方法的可行性和实效性. 相似文献
444.
The stamp-charging coke making process has some advantages of improving the operation environment, decreasing fugitive emission, higher gas collection efficiency as well as less environmental pollution. This article describes the different structure strength and high temperature thermal properties of 4 different types of coke manufactured using a conventional coking process and the stamp-charging coke making process. The 4 kinds of cokes were prepared from the mixture of five feed coals blended by the petrography blending method. The results showed that the structure strength indices of coke prepared using the stamp-charging coke method increase sharply. In contrast with conventional coking process, the stamp-charging process improved the coke strength after reaction but had little impact on the coke reactivity index. 相似文献
445.
《International Journal of Sustainable Engineering》2013,6(3):212-224
Nowadays, many countries are looking towards sustainability as a goal because our world has limited resources and serious environmental impacts. In the construction industry, the process of sustainable selection of structural material is considered one of the keys to achieve more sustainable construction. In this paper, the theories of decision making are utilised to develop an approach for evaluation and ranking the structural materials over their total life based on sustainability criteria using multi-attribute decision-making methods. One of them is Analytical Hierarchy Process which is utilised to build the problem hierarchical structure and assign weights of the predetermined sustainable factors. The other is Technique for Order Preference by Similarity to the Ideal Solution which is utilised to rank the structural materials within both each material life cycle phase and the complete material life cycle phases. The third is the concept of entropy by Shannon to evaluate the weight factor for each phase of material life cycle. The proposed approach presents an objective, systematic and comprehensive method for the sustainable ranking of materials that links between the structural element design and the sustainable selection of materials. 相似文献
446.
447.
Gail Lipfert Andrews L. Tolman Marc C. Loiselle 《Journal of the American Water Resources Association》2004,40(4):999-1010
ABSTRACT: Delineation of contributing areas for wellhead protection around supply wells drilled into bedrock in Maine, USA, is currently achieved by assigning a fixed radius circle around the well. This project develops a methodology that incorporates hydrogeologic processes and ground water modeling (MODFLOW) and accounts for variable data availability to estimate the areas that contribute water to 26 bedrock supply wells. Outcrop fracture mapping and lineament analysis are used to characterize the fracture system. Multiple simulations are constructed of each site using ranges of values for recharge, hydraulic conductivity, and anisotropy. Uncertainty in the delineation process is accounted for by portraying the delineated areas as confidence zones that are constructed by overlapping the capture zones from the multiple simulations. The results are variable and depend on the ability to characterize a site in a way that can be easily modeled. Sites with complex hydrogeology tend to have larger contributing areas that reflect the greater uncertainty in the parameters. The majority of the sites, however, produce reasonable results that provide a much more accurate depiction of the area likely to contribute to a bedrock well than the fixed radius circle. 相似文献
448.
Junchao Li Christopher M. Barnes Kai Chi Yam Cristiano L. Guarana Lin Wang 《组织行为杂志》2019,40(8):869-882
This paper advances the understanding of managerial voice endorsement based on a self‐regulation perspective. We suggest that although managers might potentially benefit more from employees' upward voice when they are more depleted, they are paradoxically less likely to diligently process or endorse such voice under ego depletion. We draw from ego depletion theory and argue that when managers are more depleted of their self‐control resources, they will spend less cognitive effort in processing voice. In turn, they tend to reject employee voice due to status quo bias and confirmation bias. We further suggest that the detrimental effect of ego depletion on voice endorsement is stronger when the voicing employee is perceived as having low expertise. We conducted an experience sampling study surveying 62 managers about voice events they encounter at work over 10 days (Study 1) and an experiment with 198 managers (Study 2). These two studies support our hypotheses. We discuss the theoretical and practical implications of our findings. 相似文献
449.
Mariusz Dąbrowski Jarosław Górski 《International journal of occupational safety and ergonomics》2019,25(2):278-286
One of the most serious causes of accidents in furniture making is kickback of machined material. The aim of this study was to determine the influence of the milling tool setup on hazards associated with kickback in furniture making. The speed of kickback was accepted as the measure of these hazards. The experiment involved controlled changes in milling tool setup, projection of cutting knives over the body of the milling tool, number of cutting knives and clearance angle. Multifactor analysis of variance was applied to the results of individual experiments, showing statistically significant factors and their interactions. Inspection and analysis of traces left by the cutting knives of the tools on the test pieces made of wood materials supported inferential statistics. The obtained results verified some common opinions and ideas on the impact of the milling tool setup on the hazards resulting from kickback in furniture making. 相似文献
450.
为了解决当前县(市)防震减灾工作部门开展地震应急处置工作时,所依据地震应急预案缺乏针对性、可操作性的问题。考虑不同县(市)自然地理、社会经济等环境的不同,提炼影响县(市)地震应急处置的主要因素,构建不同烈度下基于多因素的地震应急处置模型;在此基础上设计,并以国家可持续发展实验区四川省丹棱县为例,研发面向县(市)的地震应急处置辅助决策系统;通过在丹棱县境内假想设定6.5级地震对系统进行测试,结果表明:地震发生后,系统能按烈度分阶段快速产出具有区域特征且操作性较强的地震应急处置方案,可为县(市)地震应急处置的科学决策等提供有效的辅助决策建议。 相似文献