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61.
INTRODUCTION: Research suggests safety climate (SC) is a strong predictor of safety-related outcomes in organizations. This study explores the relationship between six SC dimensions and four aspects of work-related driving. METHOD: The SC factors measured were "communication and procedures," "work pressures," "relationships," "safety rules," "driver training," and "management commitment." The aspects of self-reported occupational driving measured were traffic violations, driver error, driving while distracted, and pre-trip vehicle maintenance. RESULTS: Hierarchical regression analyses revealed that the SC factors accounted for significant amounts of variance in all four aspects of work-related driving, over and above the control factors of age, sex, and work-related driving exposure. However, further investigation indicated certain SC factors (particularly safety rules, communication, and management commitment) were more strongly related to specific aspects of work-related driving behavior than others. Together, the SC factors were better able to predict self-reported distraction from the road than the other aspects of driving behavior measured. Implications for occupational safety, particularly for the management of work-related drivers are discussed.  相似文献   
62.
Coral reefs provide shoreline protection, biological diversity, fishery harvests, and tourism, all values that stem from the physically-complex coral infrastructure. Stony corals (scleractinians) construct and maintain the reef through deposition of calcium carbonate. Therefore, assessment of coral reefs requires at least some measurement endpoints that reflect the biological and physical condition of stony corals. Most monitoring programs portray coral quantity as live coral cover, which is the two-dimensional proportion of coral surface to sea floor viewed from above (planar view). The absence of the third dimension, however, limits our ability to characterize coral reef value, physiology, health and sustainability. A three-dimensional (3D) approach more realistically characterizes coral structure available as community habitat and, when combined with estimates of live coral tissue, quantifies the amount of living coral available for photosynthesis, growth and reproduction. A rapid coral survey procedure that coupled 3D coral quantification with more traditional survey measurements was developed and tested in the field. The survey procedure relied on only three underwater observations – species identification, colony size, and proportion of live tissue – made on each colony in the transect. These observations generated a variety of metrics, including several based on 3D colony surface area, that are relevant to reef management.  相似文献   
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64.
提出了一种针对简单多边形的快速三角化算法。该算法利用了多边形的方向性,计算出了多边形每个顶点凹凸性。根据多边形的凹点和凸点的特性,将多边形逐步分割成一系列不可再分割的三角形,实现了多边形的三角化。  相似文献   
65.
Abstract:  The occurrence of fauna in commercial plantations is often associated with structural complexity. Through a meta-analysis, we tested whether the structural complexity of plantations could enhance bird species assemblages and whether bird assemblages respond differently depending on taxonomic affiliation, body size, and diet. Our analyses included 167 case studies in 31 countries in which bird assemblages in forests and plantations were compared and 42 case studies in 14 countries in which bird assemblages in plantations of different structural complexity were compared. Species richness, but not abundance, was higher in forests than in plantations. Both species richness and abundance were significantly higher in complex than in structurally simple plantations. Taxonomic representation and body size did not differ between forest and plantations, except that there were fewer insectivorous birds in plantations than in forests. In the comparison of simple versus complex plantations, abundance of all taxonomic and dietary groups was higher in complex plantations. Body size did not affect bird species richness or abundance. Independent of the type of plantation, bird richness and abundance were greater in structurally complex plantations. Enhancing the structural complexity of plantations may mitigate their impact and offer habitat for some native species.  相似文献   
66.
ABSTRACT

In organizational sustainability, the economic dimension is recognized as having a very important role. However, the discussion regarding whether it is exclusively the economic dimension that has the power to induce the other sustainability dimensions is far from agreement. The purpose of the present paper is to analyze the perceptions regarding the existence of mutual influences between the economic dimension of sustainability and the other sustainability dimensions – environmental, social and cultural – in a relevant Portuguese economic sector: the metal industry. The analysis and statistical tests performed with the 211 collected answers led to the conclusion that the influence exerted by the economic dimension on the other sustainability dimensions is perceived as dominant, both in present and future perspectives. The results also show the perception that the economic dimension is equally influenced by the environmental and social dimensions, and in a less extent, by the cultural dimension, and that all these mutual influences are perceived to increase in the future. The existence of organizational management systems has a positive effect on the perceptions regarding the existence of mutual influences between sustainability dimensions, but only for those companies with more than one certified management system. These results confirm that organizational management systems are connected to higher degrees of awareness regarding sustainability issues. Given that the great majority of the sampled industries are SMEs, the results obtained in this research demonstrate that the existence of mutual influences between sustainability dimensions is recognized even in small-sized industries.  相似文献   
67.
面向复杂的生态环境系统,将生物多样性保护的全部要素在短时间内全部加以规则化、制度化可能会带来高昂的制度转型成本并形成负面反馈,延长有效治理的时限。生物多样性保护的复杂性、生物安全事件的突发性都需要治理系统快速做出反应,提供弹性、包容的治理机制。模糊治理的嵌入可以对精细化治理形成有效补充。这一模式将打破行政主体的关系限制,突破行政区域地理的空间限制,推进生物多样性保护协调行动。要完成这一任务,既需要完善清晰、可预测的生物多样性制度框架,为模糊治理提供规则条件,也需要适度模糊治理主体的组织关系,为模糊治理提供机制条件,还需要完善生物多样性治理的层级网络,模糊治理区域的地域关系,为模糊治理提供策略条件。  相似文献   
68.
While it is commonly acknowledged that the ecosystemic, and the inter- and intra-specific diversity of natural life is under threat of being irremediably lost, there is much less awareness that the diversity in agro-ecosystems is also under threat. This paper is focused on the biodiverse agro-ecosystems generated by landraces (LRs), i.e., farmer-developed populations of cultivated species that show among- and within-population diversity and are linked to traditional cultures. The aim of this work is to arouse concern about their loss, to explain how they can be conserved, and to discuss values that support maintaining and/or restoring on-farm agro-biodiversity. Although agriculture has relied on biodiverse agro-ecosystems for millennia, most of them have disappeared or are disappearing due to profound transformations in the socio-economic context. This is discussed with particular reference to the European situation. The positive values of LRs and LR systems that support their conservation are discussed along with possible objections. The conservation of LRs and LR systems can be well justified on ethical grounds. In particular, the complex intertwining of the biological and cultural contexts of LR systems, which continuously creates new adaptive responses to the changing socio-economic and eco-physical processes, is a value that strongly motivates conservation, particularly when the needs of future generations are considered.  相似文献   
69.
基于单元特性的通风系统可靠性分配方法研究   总被引:1,自引:2,他引:1  
通风系统可靠性分配是优化矿井通风系统可靠性设计、保障安全生产和日常管理的一项重要指标。在系统可靠性设计过程中 ,如何根据具有一定冗余度的通风系统进行可靠性指标的分配或再分配 ,是现场通风安全技术管理人员面临的一个重要课题。笔者以可靠性工程理论为指导 ,针对矿井通风系统时变、可修的特点 ,分别从基于单元相对易损度、基于单元重要复杂度以及基于单元故障频率角度对矿井通风系统可靠性进行了再分配方法研究 ,并以矿用主通风机系统为实例 ,进行了应用分析和验证。实践证明 ,采用上述分配方法的最终分配结果均接近期望的目标值 ,且满足不低于目标值的要求。该分配方法的研究 ,可为矿井通风系统可靠性优化设计提供一条新的研究思路。  相似文献   
70.
Ecosystem management links human activities with the functioning of natural environments over large spatial and temporal scales. Our examination of Greater Yellowstone and Georges Bank shows similarities exist between human uses, administrative characteristics, and some biophysical features. Each region faces growing pressures to replace traditional extractive uses with more sustainable extractive or noncommodity uses coupled with concern about endangered species. Ecosystem management as a set of practical guidelines for making decisions under evolving expectations is far from complete, and it embodies new demands on individuals and institutions. In each system these challenges are considered relative to: the public's symbolic understanding of the management challenge, ecosystem management ambiguities, information availability, information use, administrative setting, and learning capabilities of governance organizations Progress in making ecosystem management operational may occur as refinements in content and approach make it an increasingly attractive option for resource users, the public, and government officials.  相似文献   
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