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1.
针对正在兴起的集科学、政策、管理于一体进行综合分析的"生态区评价”理论与方法,本项研究就生态区评价中的空间范围确定的方法进行了探讨,并就其对全球变化的响应机制进行了讨论.提出把自然单元、社会单元和信息单元进行复合(集成)的概念化模型,并以此论证了生态区重要性与安全性水平排序的系统分析法.  相似文献   

2.
Assessing landslide exposure in areas with limited landslide information   总被引:4,自引:2,他引:2  
Landslide risk assessment is often a difficult task due to the lack of temporal data on landslides and triggering events (frequency), run-out distance, landslide magnitude and vulnerability. The probability of occurrence of landslides is often very difficult to predict, as well as the expected magnitude of events, due to the limited data availability on past landslide activity. In this paper, a qualitative procedure for assessing the exposure of elements at risk is presented for an area of the Apulia region (Italy) where no temporal information on landslide occurrence is available. Given these limitations in data availability, it was not possible to produce a reliable landslide hazard map and, consequently, a risk map. The qualitative analysis was carried out using the spatial multi-criteria evaluation method in a global information system. A landslide susceptibility composite index map and four asset index maps (physical, social, economic and environmental) were generated separately through a hierarchical procedure of standardising and weighting. The four asset index maps were combined in order to obtain a qualitative weighted assets map, which, combined with the landslide susceptibility composite index map, has provided the final qualitative landslide exposure map. The resulting map represents the spatial distribution of the exposure level in the study area; this information could be used in a preliminary stage of regional planning. In order to demonstrate how such an exposure map could be used in a basic risk assessment, a quantification of the economic losses at municipal level was carried out, and the temporal probability of landslides was estimated, on the basis of the expert knowledge. Although the proposed methodology for the exposure assessment did not consider the landslide run-out and vulnerability quantification, the results obtained allow to rank the municipalities in terms of increasing exposure and risk level and, consequently, to identify the priorities for designing appropriate landslide risk mitigation plans.  相似文献   

3.
地质流体状态方程   总被引:1,自引:0,他引:1  
几乎所有的地球化学过程都有地质流体参加, 定量地了解地质流体的物理化学性质是定量研究地球化学过程的基础.100多年以来, 广大化学和实验地球化学工作者做了大量的实验测定工作, 可是所有这些工作之和, 仅仅覆盖地球范围内一个不大的温压空间, 远远不能满足地球化学研究的需要.近年来, 我们试图通过分子水平上的研究, 结合热力学和统计力学方面的知识, 在重现前人实验结果的基础上, 研究实验工作者没有或不能研究的温压和成分空间, 得到了一系列能够精确预测地质流体在广阔的温压范围内的物理化学性质的状态方程.这些状态方程不仅能够重现实验数据, 而且具有良好的外延能力, 可以应用于地球化学领域诸多方面的研究.重点讨论了几个状态方程(包括纯流体状态方程含水溶液状态方程和含盐-水-气的状态方程) 在预测流体的溶解度、相平衡、化学位和PVT性质方面的应用.简要介绍了近年来笔者应用分子动力学和蒙特卡罗模拟在地质流体研究方面所取得的成果   相似文献   

4.
用改进后的BP神经网络评价黄土质边坡稳定性   总被引:12,自引:0,他引:12  
首先介绍了改进BP神经网络性能的几种方法;在此基础上,考虑影响黄土质边坡稳定性分析的各种自然因素,包括坡高,坡比,强度指数,土何内摩擦角,土体容重,空隙水压力系数以及地震烈度统方法的计算结果进行逐一对比,对比结果证明了该方法能够满足一般黄土质边坡稳定性评价的精度要求;另一方面,由于方法的改进大大减少了网络的计算时间,使得黄土质边坡稳定性的评价更为便捷迅速,从而证明该方法具有一定的推广应用价值。  相似文献   

5.
Multi-criteria decision-making methods support decision makers in all stages of the decision-making process by providing useful data. However, criteria are not always certain as uncertainty is a feature of the real world. MCDM methods under uncertainty and fuzzy systems are accepted as suitable techniques in conflicting problems that cannot be represented by numerical values, in particular in energy analysis and planning. In this paper, a modified TOPSIS method for multi-criteria group decision-making with qualitative linguistic labels is proposed. This method addresses uncertainty considering different levels of precision. Each decision maker’s judgment on the performance of alternatives with respect to each criterion is expressed by qualitative linguistic labels. The new method takes into account linguistic data provided by the decision makers without any previous aggregation. Decision maker judgments are incorporated into the proposed method to generate a complete ranking of alternatives. An application in energy planning is presented as an illustrative case example in which energy policy alternatives are ranked. Seven energy alternatives under nine criteria were evaluated according to the opinion of three environmental and energy experts. The weights of the criteria are determined by fuzzy AHP, and the alternatives are ranked using qualitative TOPSIS. The proposed approach is compared with a modified fuzzy TOPSIS method, showing the advantages of the proposed approach when dealing with linguistic assessments to model uncertainty and imprecision. Although the new approach requires less cognitive effort to decision makers, it yields similar results.  相似文献   

6.
昆明市东川区是我国最著名的泥石流分布区。基于社会经济发展的需要,联系泥石流研究的相关理论成果,使用泥石流危险性评价模型,结合GIS软件对昆明市东川区泥石流进行危险性评价,得出了昆明市东川区各乡镇的泥石流危险度。易损性评价是泥石流灾害风险性评价的一部分,根据每个乡镇的经济、人口等指标结合国内有关易损性的理论,建立东川区的泥石流易损性评价模型,从而对东川区以各乡镇为单位进行了易损性评价,得出了各乡镇的易损度。有了易损度和风险度,利用联合国提出的自然灾害风险表达式两项相乘得出了东川区的风险度。最后,使用ARCGIS9.0的制图输出功能,对该区域的泥石流风险性进行了分区和制图,给出了昆明市东川区泥石流风险性评价图,使该地区的泥石流风险性评价有了新的以乡镇为单元的量化指标,更好的服务于当地防灾减灾和经济社会建设。  相似文献   

7.
宋波  曹野 《岩土力学》2013,34(Z1):234-240
目前爆破震动荷载作用下地下围岩稳定性判别主要依靠单一强度因子的独立阈值稳定性判据,这类判据多为定性分析,没有同时考虑爆破震动三要素的综合作用效果,且未建立稳定性判据与巷道围岩破坏程度之间的定量关系,在实际工程应用中存在一定的缺陷和不足。通过建立爆破荷载作用下的不同类别巷道围岩有限元模型,提取巷道围岩的响应信号,基于小波变换理论建立时间能量密度函数分析巷道围岩响应信号的时、频域特征,进而将时间能量密度曲线与时间轴围成的面积TEDI作为评估爆破震动效应的判别指标,建立了TEDI与巷道围岩损伤程度的定量关系,为进一步完善基于小波能量理论的巷道围岩损伤预警体系奠定基础。  相似文献   

8.
Social vulnerability assessment of natural hazards aims to identify vulnerable populations and provide decision makers with scientific basis for their disaster prevention and mitigation decisions. A new method based on remote sensing is presented here to establish a model of social vulnerability for county-scale regions that lack of relative data. To calculate population density, which is the most important indicator in social vulnerability assessment, first, a statistical model is established to estimate the population on village level. Then a new concept defined as “population density based on land use” is created to replace the arithmetic population density. The former has taken the dynamic human distribution related to land use into account; thus, it can map the population distribution more realistically. The other two indicators are age structure and distance to hospital. The application of this method to the Luogang District of Guangzhou, South China demonstrated its capability of providing high spatial resolution and reasonable social vulnerability for social vulnerability assessment of natural hazards.  相似文献   

9.
Risk management in urban planning is of increasing importance to mitigate the growing amount of damage and the increasing number of casualties caused by natural disasters. Risk assessment to support management requires knowledge about present and future hazards, elements at risk and different types of vulnerability. This article deals with the assessment of social vulnerability (SV). In the past this has frequently been neglected due to lack of data and assessment difficulties. Existing approaches for SV assessment, primarily based on community-based methods or on census data, have limited efficiency and transferability. In this article a new method based on contextual analysis of image and GIS data is presented. An approach based on proxy variables that were derived from high-resolution optical and laser scanning data was applied, in combination with elevation information and existing hazard data. Object-oriented image analysis was applied for the definition and estimation of those variables, focusing on SV indicators with physical characteristics. A reference Social Vulnerability Index (SVI) was created from census data available for the study area on a neighbourhood level and tested for parts of Tegucigalpa, Honduras. For the evaluation of the proxy-variables, a stepwise regression model to select the best explanatory variables for changes in the SVI was applied. Eight out of 47 variables explained almost 60% of the variance, whereby the slope position and the proportion of built-up area in a neighbourhood were found to be the most valuable proxies. This work shows that contextual segmentation-based analysis of geospatial data can substantially aid in SV assessment and, when combined with field-based information, leads to optimization in terms of assessment frequency and cost.  相似文献   

10.
As one of the major problems of geo-engineering, landslides often influence the safety of linear engineering projects that cross mountainous areas. Therefore, when selecting suitable routes for such projects, it is important to assess their susceptibility to landslides. In this paper, we used a natural gas pipeline in the northeast of the Yunnan-Guizhou Plateau of China as a case study to analyze landslide susceptibility. Based on engineering geological analogy, the analytical hierarchy process, and the least-squares method, a regional landslide susceptibility assessment model was developed and was programmed using GIS ArcEngine components under the Visual Studio.NET environment. The landslide susceptibility along the Zhong-Wu natural gas pipeline from Zhongxian County to Wuhan was assessed based on this model and classified into five levels: very safe, safe, moderate, susceptible, and very susceptible. The high accuracy and prediction capability of the model were confirmed by comparing the model results with past landslide data and performing a prediction test. The results indicated that the assessment model used in this study is reliable and can be used for landslide susceptibility assessment and route selection in other areas.  相似文献   

11.
The study of rock pillar failure mechanisms is an issue that is faced routinely in mining and civil industries. In mining operation, the establishment of several mining levels is often necessary to ensure adequate production. This result in the formation of pillars that must be recovered under often high stress conditions at later stages of excavation. It is, therefore, beneficial to develop guidelines that can be used in the design of rock pillars. The aim of this paper is to delve into the mechanisms involved in pillar failure as well as to investigate the non-linear behavior of rock pillars. An extensive numerical analysis was carried out to study the pillar deformation and failure process under natural loading conditions. Effects of pillar geometry and pillar strength parameters on pillar behavior were investigated for hard rock material typical of Canadian mining conditions. Numerical data were compared against field data recorded in Canadian mines. A fairly good match was achieved between numerical and field data and the conducted analysis can be used as a qualitative guideline in the design of rock pillars in underground structures.  相似文献   

12.
Risk evaluation and loss analysis is key in foreseeing the impact of disasters caused by natural hazards and may contribute effectively in improving resilience in a community through the pre-evaluation of preparedness and mitigation actions. The pilot study presented herein is for the Chilean city of Iquique, which is located at the core of a seismic gap that extends from south Perú to north Chile, and has strategic geopolitical and economic importance for the country. The region was hit April 1, 2014, by an \(M_\mathrm{w}\) 8.2 earthquake that caused only moderate damage, but seismological evidence suggests that there is still a potential for a much larger event in the region. Therefore, a careful damage assessment study is fundamental to anticipate the possible physical, social, and economic consequences that Iquique may face in the future. In this work, the HAZUS-MH platform was adapted and used to simulate a set of ten plausible physics-based future seismic scenarios with magnitudes ranging from \(M_\mathrm{w}\) 8.40 to \(M_\mathrm{w}\) 8.98, which were proposed based on an analysis of interplate locking and the residual slip potential remaining after the April 1, 2014, earthquake. Successful application of this damage assessment methodology relies on the construction of a comprehensive exposure model that takes into account regional features and a good characterization of the physical vulnerabilities. For Iquique, a large body of public and local data was used to develop a detailed inventory of physical and social assets including an aggregated building count, demographics, and essential facilities. To characterize the response of the built environment to seismic demand, appropriate HAZUS fragility curves were applied, and outcomes were validated against the damage observed in the 2014 earthquake. After satisfactory testing, a deterministic earthquake damage assessment study was carried out for the collection of predictive scenarios aimed to estimate their expected impacts. This analysis provides data for future evaluations of different physical and social mitigation measures for the city.  相似文献   

13.
This paper presents a new method for quantifying vulnerability to natural hazards in China. As an important area of vulnerability research, quantitative assessment of vulnerability has raised much focus in academia. Presently, scholars have proposed a variety of methods for quantitative assessment, which usually create an index of overall vulnerability from a suite of indicators, based on the understanding of the cause or mechanism of vulnerability. However, due to the complex nature of vulnerability, this approach caused some arguments on the indicator selection and the weight set for subindices. A data envelopment analysis?Cbased model for the assessment of the regional vulnerability to natural disasters is presented here to improve upon the traditional methods, and a new approach for the classification of vulnerability is proposed. The vulnerability to natural hazards in China??s mainland is illustrated as a case study. The result shows that the overall level of vulnerability to natural hazards in mainland China is high. The geographic pattern shows that vulnerability is highest in western China, followed by diminishing vulnerability in central China, and lowest vulnerability levels in eastern China. There is a negative correlation between the level of vulnerability and the level of regional economic development.  相似文献   

14.
Spatial analysis of anthropogenic impact on karst geomorphology (Slovenia)   总被引:1,自引:0,他引:1  
The objective of this contribution is analyzing, visualizing, interpreting and discussing the impacts of anthropogenic influences on karst geomorphology through various geomorphologically based environmental indicators. The primary data sources are digital terrain models (DTMs) as continuous surface data, supported by aerial photographs, satellite images, topographic maps and databases of natural and anthropogenic features. The sources are supplemented by written information about surface changes and in situ inspections. Spatial analyses as quantitative methods in combination with enhanced visualizations as qualitative methods performed in a geographical information system (GIS) on different data sets are introduced as an important methodology. This enables explaining many anthropogenic influences on the terrain surface (landform), which were not perceived before by classical surveying techniques and verifications.  相似文献   

15.
16.
Freitas  Gabriel  Díaz  Ismael  Bessonart  Martín  da Costa  Edwin  Achkar  Marcel 《GeoJournal》2021,86(3):1155-1171

Floods are natural processes that constitute a hazard to society when associated to improper land use. Anthropic activities in floodplains are a factor of vulnerability that converts a natural hazard into a threat factor, eventually leading to disaster. Nowadays, natural and social complex processes demand integrated assessments in order to improve their understanding, helping decision making over sustainable use of territory, as well as integrating society’s activity in ecosystems and potentials, restrictions and benefits that society obtain from them. In this context, the objective of this work was to build a composite vulnerability model for a floodplain under urban influence, using an integrated assessment approach. This model was based on three dimensions; threat, fragility and an ecosystem services provision. These dimensions were calculated using both primary and secondary information, and weights by specialists. Main results show that the area presents high vulnerability with an increasing gradient towards high and urbanized areas, associated with an important number and relevant ecosystem services. Also, a spatial heterogeneity of the three dimensions emerged, making evident this area’s complexity and the need of integrated assessments to approach it. The composite vulnerability model proposed presents an elevated potential for natural and social processes analysis in floodplains, which is crucial for these territory management. Moreover, these integrated dimensions could contribute to decision making in different levels, as well as generating important supplies for environmental management and land planning.

  相似文献   

17.
Sarah Wolf 《Natural Hazards》2012,61(3):1099-1113
The concepts vulnerability and risk are of great importance in the fields of climate change and natural hazards. Confusion is asserted in the terminology used by the respective communities, and a large conceptual literature has not solved this problem. This affects the communication within and between the two communities and the comparison of results from vulnerability and risk assessments. This paper argues that the main difference between methods to assess vulnerability and risk in the climate and the disaster communities is not a conceptual one, but rather different terminologies are used. This point is made using a formal framework of vulnerability to climate change that makes the structure of vulnerability and risk assessments explicit. The framework distinguishes three assessment approaches in the field of vulnerability to climate change, which recur—under different labels—in the risk assessment approaches analysed. While within each community, the same terms are ambiguously used to refer to more than one assessment approach, the confusion is enhanced between the two communities by using different labels for very similar approaches. As an application of the results, similarities and differences between two assessment tools are analysed: the Dynamic Interactive Vulnerability Assessment model (DIVA) for the case of vulnerability to climate change and the CATastrophe SIMulation model (CatSim) for risk of natural hazards.  相似文献   

18.
极端洪水灾害损失评估方法及应用   总被引:3,自引:0,他引:3       下载免费PDF全文
极端洪水灾害具有频率低、影响范围大、损失高等特点,一般常遇洪水的灾害损失评估方法难以适用。分析了极端洪水灾害的自然属性与社会属性,认为极端洪水灾害损失具有时空分布的特性,因此借鉴空间信息格网技术,分别形成了极端洪水水文特性格网与社会经济特性格网,并将其叠加得到具有空间拓扑关系和属性信息的基于GIS的极端洪水损失空间信息格网模型,从而有效地反映了极端洪水灾害的时空特性。结合极端洪水损失率数据库,可评估极端洪水灾害损失。利用该方法评估了1998年特大洪水造成哈尔滨市江南主城区的直接经济损失,实证说明该方法可用于极端洪水灾害损失的评估。  相似文献   

19.
Spyway Quarry in Dorset contains >100 tracks made by large sauropod dinosaurs walking across what was a shelly beach in the Early Cretaceous. It is the largest in situ easily accessible UK dinosaur tracksite, a unique location for the public to directly engage with dinosaurs. Following consultation on how best to open and manage the site considering its 'value', longevity, and resources available, it was left unstaffed with the track surface directly accessible. The site has been open to the elements since 2013 and to the public since 2016. We created a new photogrammetric model of the site in 2021, for comparison with an existing 2014 model to identify any changes in the trackway surface and to assess the sustainability of direct public access and weathering to the surface. To understand public use of the site, we installed a visitor counter, compiled social media reviews, and analysed photographs of visitor's movement on the quarry surface. We provide quantitative evidence for exfoliation of the track surface and reduction in the prominence of individual tracks over time primarily due to natural processes. Visitor data suggest ~10,000 people visit annually, and feedback suggests potential improvements to visitor directions and information. We do not recommend substantial changes to the site management plan given resource constraints. Our work highlights the importance of using 3D imaging techniques to document sites upon discovery and thereafter and making these data openly available to all for conservation monitoring, communication and to preserve sites' legacies.  相似文献   

20.
文章尝试性地提出岩溶水生态系统的概念,从系统的特征、功能和面临的威胁三方面论述了其内涵,基于驱动力-压力-状态-影响-响应(DPSIR)模型,综合考虑自然因素和人类活动叠加影响,构建了岩溶水生态系统健康评价指标体系;用层次分析法(AHP)确定指标权重,用综合评价法确定岩溶水生态系统所处健康状态,并将其分为很健康、健康、亚健康、不健康和病态五级。并以晋祠泉域为例,采用ArcGIS空间分析技术确定岩溶水生态系统健康评价等级。结果表明:泉域煤矿开采区处于不健康状态,东部平原区和中部径流区均处于亚健康状态,碳酸盐岩裸露区和汾河周边区域处于健康状态,分别占晋祠泉域总面积的29%、31%和40%。  相似文献   

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