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91.
碧流河水库水质状况的模糊模式识别及对策讨论   总被引:6,自引:0,他引:6  
提出了确定污染指标权重的新方法,运用陈守煜建立的模糊模式识别理论模型对大连市碧流河水库连续3a的水质进行了综合评价,并探讨了水质保护对策   相似文献   
92.

Introduction

The purpose of this study was to analyze linked crash and hospital data to determine the effect that enactment of a standard enforcement safety belt law in Ohio would have on hospital charges and direct medical costs due to motor-vehicle crashes, focusing on the impact to the state's Medicaid system.

Method

The linkage and analysis was conducted as part of the Ohio Crash Outcome Data Evaluation System (CODES) program. Current safety belt usage in Ohio stands at 82% with its secondary enforcement safety belt law.

Results

Assuming an increase in usage to 92% through standard enforcement, over $15.3 million in medical costs to Medicaid for injuries that occur in a single year could be prevented over a 10-year period. Cumulative savings could reach more than $91.2 million during the 10-year period. In addition, 161 fatalities could have been prevented in one year had all unbelted occupants who sustained a fatal injury instead chosen to wear their safety belt.

Summary and Impact on Industry

Clearly, substantial progress can be made in reducing the number of deaths and injuries, as well as medical costs associated with motor-vehicle crashes, by strengthening safety belt laws and increasing safety belt usage in Ohio.  相似文献   
93.
地震人员伤亡快速评估模型研究   总被引:2,自引:0,他引:2  
每年地震都会给社会造成巨大人员伤亡,如果震后能迅速预知地震人员伤亡数量,这对挽救生命损失是十分有意义的。统计了近10年来中国大陆数10次强震、中强震灾害损失,根据影响伤亡的主要因素,用线性回归分析法,建立地震人员伤亡快速评估模型,并对模型进行验证,使之可用于地震预警。  相似文献   
94.
目前中国由于建设项目繁多,在役塔机数量急剧上升,若不加强监管和提升控制手段,安全事故隐患会随着塔机数量的增加剧增。本文对塔机安全事故发生的主要原因进行了分析,介绍了塔机安全监控和评估系统的技术现状,对一种新研发的塔机安全监控与评估系统做了简要阐述。同时通过对试点工程的应用,指出了本塔机安全监控和评估系统的优势,为塔机的安全作业监控提供了一个新的技术方法和手段。  相似文献   
95.
Humanity's future depends on the preservation of natural ecosystems that supply resources and absorb pollutants. Rural and urban productions are currently based on chemical products made from petroleum, which are responsible for high negative impacts on the Biosphere. In order to prevent those impacts, efficient public policies seeking for sustainable development are necessary. Aiming to assess the load on the environment (considering the gratuitous contributions of natural systems—a donor's perspective) due to human-dominated process, a scientific tool called Emergy Evaluation has been applied in different production systems, including crops and farms. However, there is still a lack of emergy studies in the context of watersheds, probably due to the difficulty of collecting raw data. The present work aims to carry out an assessment of Mogi-Guaçu and Pardo watershed, through the combined use of Emergy Evaluation and Geographical Information System. The agricultural and natural land uses were considered, while urban areas were excluded. Emergy flows (expressed in seJ ha−1 yr−1) obtained for all agricultural and natural land uses were expanded for the whole watershed and the emergy indices were calculated. The results show that the watershed has: low renewability (%R = 32%); low capture of natural resources through high external economic investment (EYR = 1.86); low dependence on natural resources (EIR = 1.16); and moderate load on the environment (ELR = 2.08). Considering a scenario where sugar-cane crops, orchards and pasture areas are converted from conventional to organic management, watershed's emergy performance improved, reaching a new renewability of 38%, but it is still not enough to be considered sustainable.  相似文献   
96.
综合多学科、多领域,从生物物理、社会经济和人类健康等方面综合考虑,建立了天津市景观河流健康评价指标体系,包括6个因素24个指标。评估了水生态健康程度。寻求人为压力与天津城市河流水生态系统变化之间的联系,识别河流受损原因.验证河流管理措施的有效性,对有效保障水生态安全、科学治水、综合利用水资源等均具有一定的科学指导作用。  相似文献   
97.
The study described in this article incorporates stakeholders' views on aquatic invasion processes and combines expert analysis with information from field work into an evaluation exercise. Management scenarios are designed based on available technical data and stakeholders' perceptions. These scenarios are evaluated using the Social Multi-Criteria Evaluation framework employing the NAIADE model. Two evaluations are carried out, technical and social. Social acceptance of different management scenarios, distribution of costs and benefits, and attribution of responsibility are discussed. The case study was carried out on Lake Izabal, a body of water connected to the Caribbean Sea in Northeastern Guatemala. In 2000, local fishermen reported the presence of an alien species in the lake, the macrophyte Hydrilla verticillata. Two years later, this alien species was established around the entire lakeshore, damaging the ecosystem, endangering native species and the subsistence of local inhabitants through impacts on transportation, fishing practices, and tourism.  相似文献   
98.
相思湖湿地公园是南宁市打造"中国水城"品牌的重要建设项目,既保护了湿地资源,也发挥了巨大的生态环境、经济及社会效益.就已完成景观绿化亮化提升工程的相思湖湿地公园展开相关调查,对其生态多样性进行分析及按照相关标准计算湿地景观特征指数,评价了其现状并提出保护对策.相思湖湿地公园具有丰富的动植物资源,从水域、林地、草地、沼泽、滩涂五种景观类型的数据可以看出:水域面积占到了52.74%,说明湿地功能显著;破碎度最大的是草地跟林地,分别达到了1.29和0.81,说明南宁市生态恢复工程和绿色提升工程效果明显.相思湖湿地公园是保护和利用当地湿地资源的有效措施.  相似文献   
99.

Introduction

A converging pair of studies investigated the validity of a simulator for measuring driving performance/skill.

Study 1

A concurrent validity study compared novice driver performance during an on-road driving test with their performance on a comparable simulated driving test.

Results

Results showed a reasonable degree of concordance in terms of the distribution of driving errors on-road and errors on the simulator. Moreover, there was a significant relationship between the two when driver performance was rank ordered according to errors, further establishing the relative validity of the simulator. However, specific driving errors on the two tasks were not closely related suggesting that absolute validity could not be established and that overall performance is needed to establish the level of skill.

Study 2

A discriminant validity study compared driving performance on the simulator across three groups of drivers who differ in their level of experience - a group of true beginners who had no driving experience, a group of novice drivers who had completed driver education and had a learner's permit, and a group of fully licensed, experienced drivers.

Results

The findings showed significant differences among the groups in the expected direction -- the various measures of driving errors showed that beginners performed worse than novice drivers and that experienced drivers had the fewest errors. Collectively, the results of the concurrent and discriminant validity studies support the use of the simulator as a valid measure of driving performance for research purposes.

Impact on industry

These findings support the use of a driving simulator as a valid measure of driving performance for research purposes. Future research should continue to examine validity between on-road driving performance and performance on a driving simulator and the use of simulated driving tests in the evaluation of driver education/training programs.  相似文献   
100.
Public participatory techniques have been the focus of a large and growing body of environmental literature. There is some consensus among those who study these techniques that there is a need to develop and implement new techniques that meet certain criteria. These include that the techniques be comfortable, convenient, and satisfying to participants. Authors have also frequently called for the use of deliberative techniques, which allow participants to express and listen to a variety of perspectives regarding the issue at hand. However, the literature on public participation lacks a set of widely applicable evaluation methods to determine whether participants in techniques find them comfortable, convenient, satisfying, or deliberative. This paper reports on the implementation of two different techniques that participants scored fairly high on all of these factors, as well as the scale-based survey questions developed to measure these factors.  相似文献   
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