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311.
根据中国道路交通事故经济损失的研究现状,借鉴国外对道路交通事故经济损失研究的成功经验,提出适用于中国实际情况的交通事故社会公共机构服务损失费用构成;确定了道路交通事故社会公共机构服务损失评价指标体系。基于经济学和统计学理论,主要从警方服务、清障服务、管理部门服务和法律诉讼服务4个方面对道路交通事故社会服务损失进行了深层次理论分析与评价;构建了相应的评价计量模型;提出了我国评价交通事故社会服务损失的一些合理化建议。研究结果对科学、全面、合理地评价道路交通事故社会经济损失具有重要的实际意义。  相似文献   
312.
根据实践,介绍控制图分析法在煤矿安全管理中的应用,将控制图法应用于安全风险指标的统计分析可以对风险指标的发展趋势作出科学判断,评价系统安全状态是否有明显好转或恶化,检验安全管理及技术措施是否有效。以样本矿井为例,分别以月平均受伤人数、月平均计划外瓦斯超限次数为风险评价指标进行控制图分析。应用伤亡事故控制图进行安全管理,其主要优点是能够明确伤亡事故管理目标,掌握事故发展规律与趋势,有利于总结经验,吸取教训,在动态中进行安全管理。控制图分析法在煤矿安全管理中有着简便、实用、动态、预测等多种优点,对煤矿企业安全管理具有推广和借鉴意义。  相似文献   
313.
鉴于碗窑碾压混凝土重力坝个别变形测点测值异常现象,依据大坝变形观测资料,通过变形规律时空分析和统计模型的建立,以及影响因子的分解,合理地解释了其变形成因,从而得出碗窑水库大坝变形性态总体正常的结论。为确保大坝安全运行,通过建立有限元力学模型和混合模型,拟定了典型坝段坝顶水平位移的一级监控指标,进而更有效地监控大坝的安全性态。另外,就个别测点坝段时效有呈逐年缓慢上升的趋势,建议管理单位加强观测,并及时分析,确保工程安全运行。  相似文献   
314.
运用模糊综合评价法对矿井采掘工作面进行了通风效果的评价,先确定了影响工作面通风效果的指标,并逐一构造了其隶属函数,然后采用层次分析法定出评价指标的相对权重,最后对计算模糊评判的算法进行了分析,以此来确定采掘工作面通风效果的评价等级。以东滩煤矿部分采掘工作面的环境状况为例进行了评价,据实际考察评价结果反映,通过该评价方法得到的结果与现场完全一致。  相似文献   
315.
针对当前安全文化评价领域存在的评价方法相对简单、主观性较强等问题,基于企业安全文化的人本主体,设计以企业决策层、管理层、执行层为主体的企业安全文化指标体系;充分利用因素重构分析法和主成分分析法在数据处理上的各种优势,建立适应指标体系特征并考虑数据约束条件的企业安全文化评价模型;通过实例分析加以验证。该模型为解决企业安全文化评价中指标体系庞大复杂、样本空间小、缺少可以直接利用的历史数据等难题给出了一条具有可操作性的路径。  相似文献   
316.
危险货物道路运输系统的风险评价   总被引:7,自引:0,他引:7  
分析了危险货物道路运输系统的风险影响因素,在此基础上建立了风险评价指标体系,并采用专家咨询法确定了各指标的权重,提出了使用模糊数学综合评价法对危险货物道路运输系统进行风险评价,并通过实例对评价模型进行了验证.结果表明,利用模糊综合评价的方法对危险货物道路运输系统的风险进行研究,可以为危险货物道路运输企业和交通安全监管部门对危险货物道路运输采取有效的安全控制措施,提供有益的参考.  相似文献   
317.
Abstract: There is a significant need for a science‐based approach to interpret water‐monitoring data and to facilitate the rapid transfer of information to water resource managers and the general public. The water quality Index (WQI) is defined as a single numeric score that describes the surface water quality condition at a particular time and location. The objective of this paper is to describe the WQI concept and the approach for developing an ecoregion‐specific standardized WQI that meets the needs described above. The premise of the proposed WQI is based on categorizing scientifically documented aquatic life responses to changes in instream water chemistry. The method uses an aggregated procedure that matches the entire range of standardized probable biological responses to standardized narrative water quality evaluation categories and standardized rank score categories. The calculation of WQI and decision‐making process are performed within an Excel spreadsheet software program. The article includes examples of the proposed WQI applications that could enhance effective water resource management and facilitate timely communication of water quality conditions to water resource managers and the general public.  相似文献   
318.
Bogs are of interest to outdoor recreationists, but little information exists concerning how recreation resource managers might manage these areas to enhance visitor benefits. This study evaluates bog visitor characteristics and experiences, visual preferences, and reasons for visiting. Implications for recreational resource management of bogs include the location and design of boardwalk trails and management of understory vegetation to meet the visual preferences and motives of bog visitors.  相似文献   
319.
A mathematical model simulates the cumulative volume of debris produced from brushland watersheds. Application of this model to a 176-km2 (0.678 = mi2) watershed along the southern flank of the Central San Gabriel Mountains permits assessment of expected debris production associated with alternative fire-management policies. The political implications of simulated debris production are evaluated through a conceptual model that links interest groups to particular successional stages in brushland watersheds by means of the resources claimed by each group. It is concluded that in theory, a rotation burn policy would provide benefits to more interest groups concerned about southern California's brushland watersheds than does the current fire exclusion policy.This research was supported by the College of Agriculture and Life Sciences, University of Wisconsin-Madison, and by the Office of Water Research and Technology, USDI, under the Allotment program of Public Law 88–379, as amended, and by the University of California. Water Resources Center, as a part of Office of Water Research and Technology Project No. A-058-CAL and Water Resources Center Project UCAL-WRC-499. Support was also provided by the California Agricultural Experiment Station, Berkeley, California.  相似文献   
320.
Technetium-99 (99Tc) is formed in significant amounts (6.2% fission yield) during fission in both nuclear reactors and nuclear bombs. The effects of technetium on soybeans (Glycine max) were studied in relation to (a) cytochemical events in the apical meristems of germinating seedlings; (b) growth responses to 0, 0.04, 0.2, 1.0, 5.0, and 20.0 ppm Tc; (c) growth responses to varying levels of Tc after a prior 5-day germination on Tc-free media, and (d) response to Tc in the presence of added manganese.By 20 days, reductions in growth were evident at all levels of Tc except 0.04 ppm (Experiment 2). Root growth was most severely affected, and seedling abnormality at 20 ppm was fivefold greater than that of the controls. The effect of 20 ppm Tc was evident at 10 days when the accumulated absorption dose was approximately 25 rads. The first evidence of damage at this dose was a delay in the initiation of the first trifoliate leaf. The shoot meristem size was 1.2-fold smaller than that of the control; however, there was no cytological evidence of radiation-induced damage. Observation of mitotic figures did not reveal any chromosome aberrations, micronuclei, or chromosome bridges. The lowest level of Tc showing toxicity was 0.2 ppm which resulted in a 31% reduction in growth at 20 days. The accumulated dose was 0.5 rad (0.025 rad/day) and thus it seems unlikely that the rapid inhibition of growth and development is due to radiological toxicity. It is quite probable that the growth effects are due to chemical toxicity possibly due to nutrient competition and/or substitution in uptake or metabolism. However, extremely low doses of radiation have been shown to delay the onset of DNA synthesis (possibly by membrane effects) inTradescantia and until the actual mechanism of Tc inhibition is determined a radiation effect cannot be totally ruled out.This research was partially supported by ERDA Contract EY-76-S-02-4139  相似文献   
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