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961.
This paper describes an approach to account for asymmetric preference formation in discrete choice models used for environmental valuation. The paper draws on data from a case study on preferences for environmental change resulting from a hypothetical rural development and conservation programme in Indonesia. Local knowledge on the current state of the environment was used to define an individual-specific status quo that consistently frames changes in a range of environmental services as gains or losses matching the perceptions of the local population living in the vicinity of a National Park. I estimated choice models that included separate parameters for increases and decreases in attribute levels for the environmental services and derived the indicators of local willingness to pay (WTP) corresponding to the bidirectional changes relative to the individual-specific status quo option. I found clear evidence of an asymmetric response to increase and decrease in attribute levels relative to the status quo. Ignoring asymmetric preference formation can therefore result in biased estimates of WTP indicators and welfare measures of change in cases where the outcomes of environmental programmes can plausibly result in both an increase and a decrease relative to a reference option. Compared to a symmetrical modelling approach, the combination of simultaneously accounting for asymmetric preference formation and preference heterogeneity in the choice model yielded additional insights that may be used to inform the development of local strategies towards biodiversity conservation.  相似文献   
962.
Irrigation water management is crucial for agricultural production and livelihood security in Morocco as in many other parts of the world. For the implementation of an effective water management, knowledge about farmers' demand for irrigation water is crucial to assess reactions to water pricing policy, to establish a cost-benefit analysis of water supply investments or to determine the optimal water allocation between different users. Previously used econometric methods providing this information often have prohibitive data requirements. In this paper, the Contingent Valuation Method (CVM) is adjusted to derive a demand function for irrigation water along farmers' willingness to pay for one additional unit of surface water or groundwater. An application in the Middle Draa Valley in Morocco shows that the method provides reasonable results in an environment with limited data availability. For analysing the censored survey data, the Least Absolute Deviation estimator was found to be a more suitable alternative to the Tobit model as errors are heteroscedastic and non-normally distributed. The adjusted CVM to derive demand functions is especially attractive for water scarce countries under limited data availability.  相似文献   
963.
We examined the connection between individuals’ relationships with the natural environment and their environmental behaviors with a focus on commitment to the environment, defined as psychological attachment and long-term orientation to the natural world. Commitment is theorized to emerge from structural interdependence with the environment and to lead to pro-environmental behaviors. Close relationships research has identified three key antecedents to commitment (satisfaction, alternatives, and investments). We developed environment-specific measures of these constructs, and factor analysis verified three distinct factors. A path analysis revealed that satisfaction with the environment and investments in the environment, but not alternatives to the environment, predicted commitment to the environment. Moreover, commitment mediated the effects of satisfaction and investments on general ecological behavior and willingness to sacrifice for the environment. In regression analyses, commitment predicted general ecological behavior and willingness to sacrifice for the environment, even when controlling for ecological worldview, inclusion of nature in the self, connectedness to nature, and environmental identity. Individuals who are satisfied with and invested in the natural world are likely to be committed to the environment and act with the well-being of the environment in mind.  相似文献   
964.
通过分析影响应急系统选址的各种因素,建立衡量应急系统地址优劣的指标体系,并利用层次分析法确定各指标的权重。依据改进逼近理想解排序(TOPSIS)法的基本思路,建立应急系统优化选址模型。通过具体的实例说明,将改进TOPSIS法引入选址模型是解决应急系统优化选址问题的有效方法,是选址方法体系的一种创新思路。  相似文献   
965.

Problem

Young workers are over-represented in injury statistics. In order to develop injury prevention strategies, this study investigated time trends and predictive factors relating to safety skills, confidence, and attitudes.

Method

Annual surveys were conducted from 2006-2009 among incoming students at the University of Adelaide. The questions addressed safety training, injury experience, and health and safety perceptions.

Results

Time trends in training, perceived safety skills, confidence, and attitudes were not significant. In terms of skills and confidence, the most important correlate was safety training outside of high school (odds ratio = 1.6), especially when repeated, assessed, or in face to face mode. Feeling strongly about safety issues was best predicted by injury experience (OR = 1.7) and gender.

Discussion

These results emphasize the value of assessed training, but they are also consistent with published U.S. data, indicating no improvement over time. It is suggested that there be a more integrated approach in safety education, involving schools and workplaces.

Impact on industry

By developing an understanding of student safety perceptions and experiences, this research aims to target strategies to reduce the excess injury rate for young workers. Workplaces should be more aware of the limitations of school-based safety education and a more integrated and evidence-based approach should be developed, involving schools and workplaces.  相似文献   
966.
近年来国内各大型水电厂都相继开展安全生产标准化建设,引用和建立适合本厂的安全生产管理体系,不断地完善和规范本厂的安全管理制度,逐步地提升了大型水电厂安全生产管理水平,实现水电厂安全生产长效机制和长治久安。具体阐述了水电厂开展安全生产标准化建设的重要性,并结合二滩水电厂的安全政策与管理体系、风险预控、职业健康和持续整改等方面对安全生产标准化建设进行全面总结经验,对特大型水电厂安全生产标准化建设有一定借鉴意义。  相似文献   
967.
This study was aimed at investigating the injury mechanism of pedestrian chests in collisions with passenger vehicles of various frontal shapes and examining the influence of the local structural stiffness on the chest injury risk by using the headform impact test at the chest contact area of the vehicle. Three simulations of vehicle to pedestrian collisions were conducted using three validated pedestrian finite element (FE) models of three pedestrian heights of 177 (AM50th), 165 and 150 cm and three FE vehicles models representing a one-box vehicle, a minicar and a medium car. The validity of the vehicle models was evaluated by comparing the headform acceleration against the measured responses from headform impact tests. The chest impact kinematics and the injury mechanisms were analyzed in terms of the distribution of the von Mises stress of the ribcage and in terms of the chest deflections. The chest contact locations on the front panel and the bonnet top were identified in connection to the causation of rib fractures. The risk of rib fractures was predicted by using the von Mises stress distribution. The headform impact tests were carried out at the chest contact area on the front panel and bonnet to examine the safety performance with respect to pedestrian chest protection. In simulations of the one-box vehicle to pedestrian collisions, the chest was struck directly by the frontal structure at a high velocity and deformed substantially, since a shear force was generated by the stiff windshield frame. The acceleration of the headform was related to the rib deflections. The injury threshold of the ribcage deflection (42 mm) corresponded to the headform average acceleration of 68 G. In the minicar collision, the chest was struck with the bonnet top and cowl area at a low velocity, and the deformation was small due to the distributed contact force between the chest and the bonnet top. Besides, the ribcage deformation was too small for bridging a relation between the headform accelerations and rib deflections. In the medium car collision, the deformation mode of the chest was similar to that in the minicar collision. The chest collided with the bonnet top at a low velocity and deformed uniformly. The deflection of the ribs had an observable correlation with the headform accelerations measured in the headform impact tests. The frontal shape of a vehicle has a large influence on a pedestrian’s chest loadings, and the chest deformation depends on the size of the pedestrian and the stiffness of the vehicle. The one-box passenger vehicle causes a high chest injury risk. The headform impactor test can be utilized for the evaluation of the local stiffness of a vehicle’s frontal structure. The reduction of the headform acceleration is an effective measure for pedestrian chest protection for specific shapes of vehicles by efficacy in modifying the local structural stiffness.  相似文献   
968.
介绍了碳排放量核算的基本原理与通用方法。以某钢铁公司焦化厂CO2排放量计算为实例,对比分析了物料衡算法和经验计算法的合理性和准确性。研究发现,对于钢铁企业来说,采用IPCC方法进行CO2排放量的计算是可行的。  相似文献   
969.
人误是造成民用航空维修差错的主要因素。由于缺少实际的数据,对航空维修行业人为失误发生的规律进行研究是必要的,但是规律研究主要依赖于该领域专家的判断,很难确保一致性。为了克服这个困难得到更加准确的评估,本文将层次分析法同成功似然函数结合起来估计造成飞机/发动机/附件损坏的人误概率。该方法确定了航空器维修人员的安全态度、知识和技能、计划和监管、信息沟通等因素,对人误的影响程度以及飞机/发动机/附件损坏中常见人误的发生概率。计算结果表明,操作/试验时最容易发生飞机/发动机/附件损坏,并且提出加强组织和监管、严格按章办事等解决措施。  相似文献   
970.
Dialogue about complex science and society issues is important for contemporary conservation agendas. Conferences provide an appropriate space for such dialogue, but despite its recognized worth, best practices for facilitating active dialogue are still being explored. Face‐to‐face (FTF) and computer‐mediated communication (CMC) are two approaches to facilitating dialogue that have different strengths. We assessed the use of these approaches to create dialogue on cultural perspectives of conservation and biodiversity at a national ecology conference. In particular, we aimed to evaluate their potential to enhance dialogue through their integrated application. We used an interactive blog to generate CMC on participant‐sourced issues and to prime subsequent discussion in an FTF conference workshop. The quantity and quality of both CMC and FTF discussion indicated that both approaches were effective in building dialogue. Prior to the conference the blog averaged 126 views per day, and 44 different authors contributed a total of 127 comments. Twenty‐five participants subsequently participated in active FTF discussion during a 3‐h workshop. Postconference surveys confirmed that CMC had developed participants’ thinking and deepened FTF dialogue; 88% indicated specifically that CMC helped facilitate the FTF discussion. A further 83% of respondents concluded that preliminary blog discussion would be useful for facilitating dialogue at future conferences. Construcción del Diálogo sobre Problemas Complejos de Conservación en un Escenario de Conferencia  相似文献   
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