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501.
为更好地研究泥炭质土场地地铁车站基坑周边沉降问题,预测和评估施工时及施工后的沉降风险,在分析了泥炭质土的特点后,选择土层厚度、有机质质量分数、重度、天然含水率、孔隙比、土层埋深和压缩模量7个指标,建立沉降风险评估指标体系,并根据改进层次分析法和改进熵权法求出主观权重与客观权重,最后用理想点法耦合主客观权重求出各评价指标的综合权重;根据沉降等级分类标准,生成每个评价指标的云滴图,计算得到各评价因子的可拓云矩阵,进而将综合权重向量与可拓云矩阵相乘得到综合确定度,根据综合确定度最大原则确定样本沉降风险等级。以昆明某地铁车站施工监测数据为例,用建立的可拓云模型对泥炭质土场地的沉降风险进行评价,最终评价结果与实际监测结果吻合较好,验证了分析方法的合理性及可行性。该评价方法充分考虑了多种因素影响,明确了沉降的风险等级,评价结果为泥炭土场地上建(构)筑物的设计施工及应急处理提供了理论依据。 相似文献
502.
A vast number of prioritization schemes have been developed to help conservation navigate tough decisions about the allocation of finite resources. However, the application of quantitative approaches to setting priorities in conservation frequently includes mistakes that can undermine their authors’ intention to be more rigorous and scientific in the way priorities are established and resources allocated. Drawing on well‐established principles of decision science, we highlight 6 mistakes commonly associated with setting priorities for conservation: not acknowledging conservation plans are prioritizations; trying to solve an ill‐defined problem; not prioritizing actions; arbitrariness; hidden value judgments; and not acknowledging risk of failure. We explain these mistakes and offer a path to help conservation planners avoid making the same mistakes in future prioritizations. Seis Errores Comunes en la Definición de Prioridades de Conservación 相似文献
503.
Kara Chan 《Journal of environmental management》1998,52(4):317-325
Treatment of domestic waste has been one of the major environmental problems in Hong Kong. The Government has a stated policy to advocate the minimization of waste disposal through the encouragement of waste reduction, re-use and recycling. The current study applies Ajzen's theory of planned behaviour to predict behavioural intention and actual behaviour of voluntary use of waste recycling receptacles. A systematic random sample of 173 household members in a public housing estate were interviewed. The results indicated that attitude was the major factor in predicting behavioural intention, followed by behavioural control and social norms. Attitude, subjective norm and perceived control together explained 44% of the variance of behavioural intention. Perception of mass media as a major source of subjective norm was first introduced and tested. Mass communication stood out as one of the major sources of influence in establishment of subjective norms. The study has the implication that more publicity messages should be put on the mass media to promote green behaviours. 相似文献
504.
Leaders face a challenge to simultaneously motivate workgroups and the individuals within them. Recent criticisms highlight the need to deconstruct broad leadership constructs to offer better theoretical insight into the effects of specific leadership behaviors on groups versus individuals. We address this call by exploring the effects of group‐focused and individual‐focused aspects of transformational leadership. Applying social identity theory, we theorize that group‐focused transformational leadership is key to fostering felt obligation, motivating helping behavior, and enhancing group performance, whereas individual‐focused leadership may only foster helping when individuals also feel a sense of obligation toward their workgroup. In a field study of 260 employees reporting to 36 supervisors in a skilled trade company, we find support for these predictions using multilevel structural equation modeling and multilevel mixed effects modeling. Thus, group‐focused (vs. individual‐focused) transformational leadership and subsequent felt obligation are important antecedents for encouraging helping and, in turn, workgroup performance. 相似文献
505.
MARK A. BURGMAN HELEN M. REGAN LYNN A. MAGUIRE MARK COLYVAN JAMES JUSTUS TARA G. MARTIN KRIS ROTHLEY 《Conservation biology》2014,28(2):322-332
Voting systems aggregate preferences efficiently and are often used for deciding conservation priorities. Desirable characteristics of voting systems include transitivity, completeness, and Pareto optimality, among others. Voting systems that are common and potentially useful for environmental decision making include simple majority, approval, and preferential voting. Unfortunately, no voting system can guarantee an outcome, while also satisfying a range of very reasonable performance criteria. Furthermore, voting methods may be manipulated by decision makers and strategic voters if they have knowledge of the voting patterns and alliances of others in the voting populations. The difficult properties of voting systems arise in routine decision making when there are multiple criteria and management alternatives. Because each method has flaws, we do not endorse one method. Instead, we urge organizers to be transparent about the properties of proposed voting systems and to offer participants the opportunity to approve the voting system as part of the ground rules for operation of a group. Sistemas de Votación para Decisiones Ambientales 相似文献
506.
Abstract: The economic valuation of ecosystem services is a key policy tool in stemming losses of biological diversity. It is proposed that the loss of ecosystem function and the biological resources within ecosystems is due in part to the failure of markets to recognize the benefits humans derive from ecosystems. Placing monetary values on ecosystem services is often suggested as a necessary step in correcting such market failures. We consider the effects of valuing different types of ecosystem services within an economic framework. We argue that provisioning and regulating ecosystem services are generally produced and consumed in ways that make them amenable to economic valuation. The values associated with cultural ecosystem services lie outside the domain of economic valuation, but their worth may be expressed through noneconomic, deliberative forms of valuation. We argue that supporting ecosystem services are not of direct value and that the losses of such services can be expressed in terms of the effects of their loss on the risk to the provision of the directly valued ecosystem services they support. We propose a heuristic framework that considers the relations between ecological risks and returns in the provision of ecosystem services. The proposed ecosystem‐service valuation framework, which allows the expression of the value of all types of ecosystem services, calls for a shift from static, purely monetary valuation toward the consideration of trade‐offs between the current flow of benefits from ecosystems and the ability of those ecosystems to provide future flows. 相似文献
507.
Ben Mepham 《Journal of Agricultural and Environmental Ethics》2000,13(1-2):65-78
If respect for the dignity of non-human creatures is to be an element of public policy it needs, as a first step, to be assimilated
into the common morality. It is suggested that such respect may be based on several philosophical premises. Limiting the discussion
to sentient animals, the paper reviews three of these: the concept of animal telos; the application of Rawlsian contractarianism
to the case of non-human animals as moral patients; and human attitudes to animals in the light of virtue theory. Consideration
is then given to the extent to which, by accommodating respect for the dignity of animals within the common morality, these
principles might find more substantive expression in public policy. 相似文献
508.
PAUL D. HIRSCH WILLIAM M. ADAMS J. PETER BROSIUS ASIM ZIA NINO BARIOLA JUAN LUIS DAMMERT 《Conservation biology》2011,25(2):259-264
Abstract: There is a growing recognition that conservation often entails trade‐offs. A focus on trade‐offs can open the way to more complete consideration of the variety of positive and negative effects associated with conservation initiatives. In analyzing and working through conservation trade‐offs, however, it is important to embrace the complexities inherent in the social context of conservation. In particular, it is important to recognize that the consequences of conservation activities are experienced, perceived, and understood differently from different perspectives, and that these perspectives are embedded in social systems and preexisting power relations. We illustrate the role of trade‐offs in conservation and the complexities involved in understanding them with recent debates surrounding REDD (Reducing Emissions from Deforestation and Degradation), a global conservation policy designed to create incentives to reduce tropical deforestation. Often portrayed in terms of the multiple benefits it may provide: poverty alleviation, biodiversity conservation, and climate‐change mitigation; REDD may involve substantial trade‐offs. The gains of REDD may be associated with a reduction in incentives for industrialized countries to decrease carbon emissions; relocation of deforestation to places unaffected by REDD; increased inequality in places where people who make their livelihood from forests have insecure land tenure; loss of biological and cultural diversity that does not directly align with REDD measurement schemes; and erosion of community‐based means of protecting forests. We believe it is important to acknowledge the potential trade‐offs involved in conservation initiatives such as REDD and to examine these trade‐offs in an open and integrative way that includes a variety of tools, methods, and points of view. 相似文献
509.
为了能够解释和预测机务维修人员的故意违章行为,探究故意违章行为的作用机理,以计划行为理论为基础框架,增加个人需要、管理层态度及工作压力因素,并探究影响因素之间的作用关系.对398份机场和航空公司机务维修人员的问卷调查数据进行信度和效度分析,然后利用结构方程模型的方法对假设的因果关系模型进行验证,并得到标准化路径系数.结果表明:感知行为控制、工作压力及个人需要对违章动机的正向影响作用显著;管理层态度和主观规范通过行为态度的中介作用间接影响违章动机;违章动机对违章行为的正向影响作用显著. 相似文献
510.
突变理论视角下突发群体事件演化机理研究 总被引:2,自引:0,他引:2
为探究突发群体事件各阶段的现象、动因和突变点等演化问题,通过剖析突发群体事件影响因素,将事件影响因素分为内在动因和外在诱因,以平息和爆发2种状态作为突发群体事件演化的趋势,构建突发群体事件演化模型,根据该模型解释突发群体事件各阶段的演化现象,找到突变点,分析演化趋势。结果表明:突发群体事件在内在动因和外在诱因的综合作用下,事件发展由量变到质变演化的3个层级阶段,其中,突变点对突发群体事件爆发起决定作用。 相似文献