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791.
以某大型危险化学品储运企业为背景,对重大危险源应急救援信息系统进行研究,首先对重大危险源应急救援过程中各种信息需求进行分析,将信息分为基础信息、预防信息和救援信息3个方面;然后在单机和网络两种版本硬件结构比较的基础上,以工艺参数传感器、泄漏传感器、火灾报警器、应急设备控制器等主要设备为基础构建了单机版的硬件结构;最后,采用C/S软件结构,运用组件式GIS技术,从系统的总体结构、数据库结构以及功能设计等几个方面对应急救援信息系统进行了研究。  相似文献   
792.
Abstract: Mapping stream channels and their geomorphic attributes is an important step in many watershed research and management projects. Often insufficient field data exist to map hydromorphologic attributes across entire drainage basins, necessitating the application of hydrologic modeling tools to digital elevation models (DEMs) via a geographic information system (GIS). In this article, we demonstrate methods for deriving synthetic stream networks via GIS across large and diverse basins using drainage‐enforced DEMs, along with techniques for estimating channel widths and gradient on the reach scale. The two‐step drainage enforcement method we used produced synthetic stream networks that displayed a high degree of positional accuracy relative to the input streams. The accuracies of our estimated channel parameters were assessed with field data, and predictions of bankfull width, wetted width and gradient were strongly correlated with measured values (r2 = 0.92, r2 = 0.95, r2 = 0.88, respectively). Classification accuracies of binned channel attributes were also high. Our methodology allows for the relatively rapid mapping of stream channels and associated morphological attributes across large geographic areas. Although initially developed to provide salmon recovery planners with important salmon habitat information, we suggest these methodologies are relevant to a variety of research and management questions.  相似文献   
793.
地理信息系统(GIS)平台采购成本高、信息发布缺乏有效通用方法,使利用其进行二次开发的模式难以符合一些应急救援信息系统建设实际需要。万维网联盟制定的可缩放矢量图形(SVG)为解决这些问题提供了契机。在评价SVG作为下一代网络矢量图形开放标准的优势基础上,对如何以SVG为基础构建应急救援网络地理信息系统(WebGIS)进行了深入分析;介绍了用SVG设计应急救援专题电子地图的特色与实现方法,然后针对该专题对基于SVG的WebGIS架构进行了剖析与优化设计,并引入了重大危险源元数据库与应急救援方法库两个概念,最后给出一个重大危险源应急救援信息系统的框架。以该技术建立的应急救援WebGIS无平台依赖性,网络发布与交互便捷,开发具有伸缩性,适合不同层次应用需求。  相似文献   
794.
本文在对中国地震灾害现状分析的基础之上,依据地震工作三大体系的要求和建设首都圈防震减灾系统工程的经验,提出了在我国建立地震灾害系统工程的设想,并对该系统进行了初步的设计和论证。分析研究表明,地震灾害系统工程可以涵盖地震工作的各个方面,并且具有系统化、法制化及高科技等特点,对我国实现减轻地震灾害的目标具有积极的推进作用。  相似文献   
795.
Solid major accident prevention management is characterized by efficient and effective risk assessments. As a means of addressing the efficiency aspect, decision support analysis software is becoming increasingly available. This paper discusses the results of a survey of decision support tools for investigating (internal and external) major hazards in the chemical industry. The most significant features, such as the usability and the functionality of the toolkits are discussed. Toolkit characteristics are analyzed in the light of the different major risk decision process stages. Consequently, valuable supportive information for company decision makers purchasing such software is given. Furthermore, conclusions are drawn and recommendations are formulated for establishing priorities for future risk toolkits developments.  相似文献   
796.
The solution with the aid of the hybrid computer of the partial and total differential equations for an integrated surface water groundwater system is described. A versatile computing technique has been developed to make a rapid and accurate study of the groundwater response due to varying inputs (deep percolation) or outputs (evapotranspiration) from the groundwater system. Spatial variations in basic vegetation phenomena, such as pattern, and hydrological parameters, are represented by means of a grid network which also allows the input of variable boundary conditions. The model is applied to an area in Columbia, South America which is subject to high water-table conditions. Various reclamation schemes and management practices under conditions of irrigated agriculture are assessed.  相似文献   
797.
The paper describes a model designed for analysing interrelated nitrogen (N) fluxes in farming systems. It combines the partial N balance, farm gate balance, barn balance and soil surface balance, in order to analyse all relevant N fluxes between the subsystems soil–plant–animal–environment and to reflect conclusive and consistent management systems. Such a system approach allows identifying the causes of varying N surplus and N utilisation.The REPRO model has been applied in the experimental farm Scheyern in southern Germany, which had been subdivided into an organic (org) and a conventional (con) farming system in 1992. Detailed series of long-term measuring data are available for the experimental farm, which have been used for evaluating the software for its efficiency and applicability under very different management, yet nearly equal site conditions.The organic farm is multi-structured with a legume-based crop rotation (N2 fixation: 83 kg ha−1 yr−1). The livestock density is 1.4 LSU ha−1. The farm is oriented on closed mass cycles.The conventional farm is a simple-structured cash crop system based on mineral N (N input 145 kg ha−1 yr−1). Averaging the years 1999–2002, the organic crop rotation reached, with regard to the harvested products, about 81% (6.9 Mg ha−1 yr−1) of the DM yield and about 93% (140 kg ha−1 yr−1) of the N removal of the conventional rotation. Related to the cropped area, the N surplus calculated for the organic rotation was 38 kg ha−1 yr−1 versus 44 kg ha−1 yr−1 for the conventional rotation. The N utilisation reached 0.77 (org) and 0.79 (con), respectively. The different structure of the farms favoured an enhancement of the soil organic nitrogen stock (35 kg ha−1 yr−1) in the organic crop rotation and caused a decline in the conventional system (−24 kg ha−1 yr−1). Taking account of these changes, which were substantiated by measurements, N surplus in the organic rotation decreased to 3 kg ha−1 yr−1, while it increased to 68 kg ha−1 yr−1 in the conventional system. The adjusted N utilisation value amounted to 0.98 (org) and 0.69 (con), respectively.  相似文献   
798.
公共事务的积累只是为制度化解决提供了必要性,当政者维护政权的根本利益需要决定了公共事务处理的优先序列。客观问题的属性和解决的迫切程度只有在政府最高层统治集团认为维系权力存续的手段具备充分的支撑条件时,才会愿意在正式制度上进行调整,为解决问题提供制度供给。新中国成立后很长一段时间内,我国环境问题并不突出,中央政府根据社会主要矛盾需要制定了以发展经济为重心的制度体系。这种制度结构使地方政府和辖区企业形成了利益共容关系。为适应竞争的需要,地方政府庇护辖区企业环境行为,机会主义地执行环境管理制度,使环境问题积累成为影响安全价值的显著因素。在国内外政治压力下,中央政府最终做出了战略调整,地方政府在中央政府制度调控下,自发地合作治理环境问题。  相似文献   
799.
介绍了中国石化长岭分公司油品储运系统中硫化氢的危害情况,包括人身伤害、设备腐蚀、部件破坏、环境污染等,针对存在的问题提出防范与改造措施,达到了安全生产与环境的要求。  相似文献   
800.
INTRODUCTION: Companies that use forklifts to load and unload trucks at loading docks are well aware of the main danger associated with this type of activity (i.e., the possibility of the forklift falling or tipping over when the truck suddenly moves away from the dock). Even if various truck restraint measures can be implemented to reduce the possibility of this type of accident, a number of hazardous incidents that result in a forklift tipping over from a loading dock still do occur regularly in day-to-day activities. This situation has brought experts to examine and evaluate the effectiveness of different measures and systems depending on the context in which they are used. METHODS: The present study touched upon both the technical and the organizational aspects of the restraint measures that could have an impact on safety. Certain elements were examined very closely, especially the failure of mechanical devices and their relation to the environment in which they are used, as well as the systemic interaction between people and the various restraint measures in use in a given context. CONCLUSION: This article presents a safety evaluation tool regarding restraint measures or systems for trucks docked at loading platforms - a tool that, of course, would take into consideration both the specific contextual aspects related to the docking bay itself, and to the plant. IMPACT ON INDUSTRY: This tool is designed to help companies choose the optimal safety measures to implement, while remaining realistic in terms of the technical and economic aspects of any given situation.  相似文献   
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