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681.
安全投资技术经济分析的研究   总被引:8,自引:4,他引:8  
在分析安全投资项目特殊性的基础上,提出了较为完整的安全投资技术经济分析方法,为企业进行安全投资决策提供了充分的依据。  相似文献   
682.
叙述了煤矿伤亡事故预测预报系统(MACF)的总体概貌。在对用户需求分析的基础上,建立了煤矿伤亡事故数据库,并重点阐述了行政区划的代码设计和基于数据库的预测预报。特别是灰色预测在煤矿伤亡事故方面的应用尚属初步探索,结果比较令人满意。  相似文献   
683.
重大危险源控制技术研究现状及若干问题探讨   总被引:17,自引:8,他引:17  
本文论述了重大危险源的定义,辨识标准及重大危险源控制系统;介绍了国外重大危险源控制技术的研究和应用进展;对建立我国重大危险源控制系统进行了探讨,提出了尽快制定我国重大工业危险源控制法规、重大危险源辨识标准以及建立分级监察和控制体系等建议。  相似文献   
684.
建筑施工要保证安全生产必须从杜绝“物的不安全状态、人的不安全行为”入手,加强教育与管理,增强法规意识,完善安全生产工作的布置、检查、监督、奖罚等企业安全行为。本文通过一起机械伤害事故分析,讨论了在宏观整体上规范企业安全行为,是促进企业安全生产最根本的环节。  相似文献   
685.
ABSTRACT: Grain transportation is a major economic activity on the multiple use Snake-Columbia River System. Congress is currently considering increased transportation user fees aimed at recapturing federal expenditures for waterway operations and maintenance. Three types of fee structure and four levels of cost recovery are evaluated using a network program model. In each case traffic is diverted away from the river to other Puget Sound ports via truck and rail transport modes. Grain shippers in the region will be adversely affected by a higher transport bill. The Lower Columbia River port economic activities will be negatively affected; however, competitive uses of the river, recreation, and hydroelectric generation will likely benefit modestly.  相似文献   
686.
Numerous backcountry and wilderness use studies have been conducted over the last decade, but nearly all of them have concentrated on peak season and summer use. This study investigates use patterns and user characteristics of winter campers, and implications for the management of winter backcountry overnight use. Use pattern data were collected from 580 backcountry use permits for both winter and summer campers of Great Smoky Mountains National Park (GSMNP). A two-page questionnaire was also mailed to 300 of the winter users to survey their characteristics, past backpacking experience, and reasons for winter camping. Backcountry permit data indicate that use patterns differ significantly between winter and summer campers, with winter campers taking shorter, weekend, destination-type trips. Winter campers engage in backcountry camping nearly twice as often during winter as other seasons of the year, both in and outside GSMNP. They are also experienced hikers that tend to avoid camping in Great Smoky Mountains National Park during the summer because of heavy visitor use. This suggests that winter backcountry campers are different enough from peak season campers that management of these two user groups may require different styles.  相似文献   
687.
经过条件优化试验,研制出氯气检测管。检测管显色长度与氯气浓度呈线性相关,对氯气标气7次测定的变异系数为13.8%,平均相对误差为5.2%,小于15%;一次测定最大相对误差为20%,小于25%,符合国家标准GB7230-87的要求。与化学法比较,2种方法测试结果无显著性差异。干扰物有溴和氯化氢气体以及高浓度二氧化氮。检测管寿命为1a。  相似文献   
688.
A 3-D Eulerian-Lagrangian approach to moving vehicles is presented that takes into account the traffic induced flow rate and turbulence. The method is applied to pollutants dispersion in a street canyon. The approach is based on CFD calculations using Eulerian approach to the continuous phase and Lagrangian approach to the "discrete phase" of moving objects - vehicles. A commercial CFD code StarCD was used into which the Lagrangian model was integrated. As an example a street canyon is taken into consideration. It has the length of 50 m and the aspect ratio of 1.27. The speed of wind was assigned values of 4, 7 and 12 m/s at the altitude of 300 m. The total height of the domain is 115 m. In the study different traffic situations are considered, namely one-way and two-way traffic with different traffic rates per lane. The predictions show that different traffic situations affect pollutants dispersion in the street canyon and that there are also differences in the pollutants dispersion in case of one- and two-way traffic.  相似文献   
689.
The varying traffic parameters such as traffic volume, speed, shape and size, and terrain roughness conditions play a vital role on dispersion of pollutants in the near field of roadways. Simulation experiments were carried out in the Environmental Wind Tunnel (EWT) to evaluate the traffic induced effects on vertical dispersion parameter (σ z ) for heterogeneous traffic conditions in the near field of roadways for evaluating the effect of variations in traffic volume, terrain roughness condition and approaching wind direction. The model vehicle movement system was fabricated and made operational in the EWT, which allowed the variation in traffic volume, speed and wind road inclination. Sixty-six hydrocarbon tracer experiments were performed to evaluate σ z in the near field of roadways for variable traffic volume, three terrain roughness conditions and two approaching wind directions (i.e., 90° and 60°). The values of σ z for heterogeneous traffic conditions were found to be higher for low roughness conditions in comparison to other two higher roughness conditions for various traffic volumes and approaching wind directions. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
690.
This paper explores the long-term effects of a nuclear accident on residents' perceptions of their physical and mental health, their trust of public officials, and their attitudes toward the future risks of nuclear power generation In their community. We find that in the period after the accident at Three Mile Island that there are constant or Increasing levels of distress reported by community residents. We conclude that the effects of a technological disaster may often be more enduring than those natural disaster and that greater research efforts should be made to Investigate the long-term consequences of man-made catastrophies of all types.  相似文献   
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