森林火险的序贯分析初探

本文利用森林着火危险度指标属于正态分布的特点,根据正态型序贯分析的原理,提出了确定林火危险性的序贯分析方法;建立了长白山林区5个站点森林火险的“安全域”与“危险域”的模型;并以东岗(长白山西坡)为例,作了正态型序贯分析全过程的应用示例。结果证明,利用正态型序贯分析来确定林火的等级是可行的、可靠的,具有实用价值。     

Community response to hazard information

The impact of flood hazard information on public acceptance of a selected flood mitigation strategy was assessed by an analysis of the content of newspaper reports of community reaction and letters to the editor. The impact of personal delivery of a flood hazard map on individual perception of risk and attitude to such information was assessed using personal interviews. The results indicated that media coverage of the flood hazard information reduced public criticism of the works. This result must be partially attributable to the dramatic style of media coverage and the fact that the media only emphasized the positive value of the works. The interview demonstrated that personal delivery of the information raised perception of risk, improved comprehension of flood risk, had no impact on acceptability of risk but discouraged some respondents from seeking such information in the future. Factors to explain the last negative change were identified to be the format of the map sheet and low salience of flood hazard. On the basis of all results, methods to improve community response to hazard information are provided.     

用伴随方法对毒气泄漏事件进行危害评估

由于自然、人为等因素造成的有毒气体泄漏事件随时威胁着人们的生命安全。对于这类突发事故进行危害评估 ,在应急救援中 ,可以给决策者提供参考 ,使之采取有效措施 ,最大限度地降低事故危害程度 ,减少事故恶果及引起的恐慌。由于毒气泄漏位置事先无法确定 ,如果用常规方法进行逐点评估 ,将面临着巨大的计算量而难以进行。笔者发展了一种伴随方法 ,对风险函数的表达式进行等价变形 ,通过求解伴随方程 ,可以一次求得任意位置的毒气泄漏的风险值 ,大大降低计算量和工作量。此法在化学工厂和仓库设置 ,煤气网铺设和监测点选取 ,城市应急中心设置等多种安全规划中均有重要价值 ,为快速危害评估 ,降低化学事故危害提供了有力的研究工具和实用方法。     

基于主逻辑图的安全风险建模研究

概率风险评估已成为研究复杂系统安全风险较为成熟的方法 ,其风险模型的建立是基于故障树/事件树的 ,风险分析具有众多的静态特性。然而 ,大的复杂系统往往存在诸多动态因素 ,在风险研究需要考虑这些动态因素的情况下 ,基于传统故障树 /事件树的模型则难以提供支持。笔者对此进行了分析 ,提出了基于主逻辑图的安全风险建模 ;主要介绍了主逻辑图的概念及其建模方法 ,并对模型进行了分析 ;在此基础上 ,基于主逻辑图分析事故场景 ,对场景风险的量化评估进行了简要介绍 ,并结合某核反应堆例子进行了分析。     

People's Perception About Participatory Developmental Programs: Lessons from the Mountain Risk Engineering Program in the Indian Central Himalaya

The Indian Himalayan Region (IHR) is suffering from environmental degradation due to population pressure and infra-structural needs. This is coupled with a natural setting, which creates problems of accelerated soil erosion and mass wasting. In view of these environmental difficulties and the growing concern for effective restoration, there has become an urgent need for multi-disciplinary coordinated improvement schemes. The mitigation of risk arising from hazardous mass wasting processes, through a careful and systematic approach, has helped in the development of the concept of Mountain Risk Engineering (MRE). The MRE practices involve an integrated approach to solving the infra-structural engineering problems of hilly and mountainous areas through environmentally conscious cost-effective and site-specific designs. However, the role of people's participation is extremely crucial for the success of such programs. This paper analyzes the perception of the local people about the approaches adopted in MRE participatory developmental programs and throws light on the intricacies of peoples' participation.     

计算机安全技术

在当今信息时代，林业安全管理所需要的信息要实现网络化必须以计算机安全技术为基础。本文主要介绍了计算机安全技术所需要注意的一些问题，同时举例说明实现单机运行安全的几种方法。     

STREAM DISCHARGE PREDICTION VIA A GRID BASED SOIL WATER ROUTING WITH PADDY FIELDS1

ABSTRACT: A grid based daily hydrologic model for a watershed with paddy fields was developed to predict the stream discharge. ASCII formatted elevation, soil, and land use data supported by the GRASS Geographic Information System are used to generate distributed results such as surface runoff and subsurface flow, soil water content, and evapotranspiration. The model uses a single flow path algorithm and simulates a water balance at each grid element. A linear reservoir assumption was used to predict subsurface runoff components. The model was applied to a 75.6 km² watershed located in the middle of South Korea, and observed stream flow hydrographs from 1995 and 1996 were compared to model predictions. The stream flow predictions of 1995 and 1996 generally agreed with the observed flow, resulting in a Nash‐Sutcliffe efficiency R² of 0.60 and 0.62, respectively. The hydraulic conductivity for percolating water through the saturated layer affected baseflow generation. The levee height of the paddy influenced the time and magnitude of the surface runoff, depending on irrigation management. The model will be used for making low flow management decisions by evaluating the role of each land use to stream flow, especially in case of paddy decrease by gradual urbanization of a watershed.     

GIS在重庆市地质灾害信息管理系统中的应用

重庆市是我国地质灾害非常严重的省市之一。长期以来，地质灾害的发生严重地影响着其城市建设与发展。为了加强对地质灾害规律的研究以及科学地管理地质灾害信息，本文探讨了GIS技术在重庆市地质灾害信息管理系统(CQGHMIS)中的应用。该系统以MapGis和MapInfo、Mapx作为后台支持，利用Visual basic5．0中文企业版作为开发语言，具有数据采集与更新、空间检索与查询、信息时空分析与可视和信息输出以及系统说明与帮助等五大功能。     

应用GIS-ANN进行土地盐碱化危险度评价--以吉林西部平原为例

土地盐碱化可破坏生态环境，制约社会经济的可持续发展，已成为一种严重的环境灾害。应用GIS技术提取土地盐碱化和环境信息，采用关联度法分析了土地盐碱化与各环境要素之间的关系，应用人工神经网络模型(ANN)进行了盐碱化危险度评价。结果表明，吉林西部平原有53．97％的土地盐碱化危险度为Ⅳ级和V级。实践证明，应用GIS—ANN集成技术评价土地盐碱化的危险度是一种较好的方法，为土地盐碱化的防治提供了科学依据。     

利用WEBGIS实现地震灾害信息数据的管理

介绍了WEBGIS技术的特点、基本原理和实现方法，及其在管理海量地理数据中的优势，并构建了基于WEBGIS的地震灾害信息数据的主体框架。