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以提高震后恢复重建项目质量评价的准确性，提出一种基于Matlab层次分析法的震后恢复重建项目质量评价体系。层次分析法是进行准确决策的一种有效方式，但在重建项目质量评价中，评价指标繁多，数据处理分析难度较大，单独应用层次分析法的计算效果欠佳。将层次分析法与Matlab软件相结合，并经过一些技术的处理，能在短时间内获取准确的分析结果，并建立一套新的评价指标，为震后恢复重建项目的快速评估提供一种新方法、新思路，本研究对提高震后恢复重建项目质量评价的智能化水平具有一定的参考意义。 相似文献
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《华北地震科学》2015,(3)
利用国内大中城市震害矩阵为样本分析影响建筑物抗震能力的各个因素,提取出主要的震害影响因子。通过海明加权距离法计算出各城市震害矩阵之间的相似度权重,并通过灰色关联法得出各个样本城市震害矩阵与目标城市的关联度,得出差异化权重的关联度矩阵。使用得到的关联矩阵代替层次分析法中的专家打分矩阵,从而减少该方法的主观因素,使得改进层次分析法成为一种可以定量的计算方法。把海明加权距离法、灰色关联法、层次分析法分别根据其各自特点融合在一起,形成了一种全新的震害矩阵拟合算法,解决了3种方法在震害矩阵计算中的局限性。通过对上海市浦东区多层钢混结构房屋进行多元算法的震害预测证明了此种方法的可靠性和可行性。 相似文献
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三亚崖州湾是海南自贸港科技发展的前沿阵地，摸清其地质环境是科技发展规划的基础条件。选取水深、坡度、沉积物环境质量、古河道或古湖泊面积、沙波面积、沙脊面积、软土面积和软土厚度共8个影响因素，采用K-means聚类法、层次分析法和熵权法对研究区适宜性进行定量分区，共划分适宜性好、较好、中等、较差和差五个等级，分析不同影响因素对崖州湾适宜性的影响，总结五个分区的地质环境特征。研究结果表明适宜性最好区位于研究区中北部，其次是中南部，两翼地质环境质量最差，中等区镶嵌分布于崖州湾的外缘；建议优先考虑适宜性最好区进行规划开发，其次是适宜性较好区。文章先用K-means聚类法对影响因素分级，再用层次分析法和熵权法计算评价因子的主客观权重，形成一种主客观结合的科学评价方法，并运用到地质环境开发适宜性评价中，很好地划分出优选区。评价结果可为研究区开发规划及防灾减灾提供基础地质依据，同时具有良好的借鉴作用。 相似文献
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强烈地震会导致建筑物倒塌进而造成室内人员压埋，因此，把特定区域和建筑群的压埋率作为震后救援的决策指标尤为重要。但地震建筑物倒塌受多个影响因素共同作用，造成了压埋率模型的后验倒塌率评估的不确定性问题。针对这个问题采用直觉模糊层次分析法，选取了震级、震源深度、震中距、抗震设防烈度、地基和基础、建筑物结构类型和结构现状等七大影响因素进行加权分析。运用LINGO软件建模解算出了各影响因素权重，通过极大似然法估算了各影响因素对建筑物倒塌率的影响值，进而评估出了建筑物预估倒塌率，并结合先验在室率模型及其区划，建立了基于直觉模糊层次分析法的地震压埋率模型。最后以汶川灾区学校为例，进行了压埋率评估，并对其进行了误差分析。研究表明:抗震设防烈度、建筑物结构类型和结构现状是影响建筑物倒塌的主要因素；在实际评估中模型精度达到±0.15，能为震后快速应急救援提供决策辅助。 相似文献
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根据未利用地资源特点及地力评价的原理，以陕西省定边县板完滩土地开发项目为例，选取了开发项目未利用地16个地力影响因子，利用层次分析法（AHP）对各影响因子进行了权值计算和综合评价结果分析。结果表明，地貌类型是开发项目未利用地地力的最大影响因子，其次是地下水矿化状况、有机质和剖面构型，采用层次分析法进行开发项目未利用地地力评价具有较好的实用性。 相似文献
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鉴于边坡稳定性评价的复杂性及其影响因素的不确定性和模糊性,运用模糊物元分析理论,分别使用层次分析法和熵权法计算各影响因子的主、客观权重值,建立兼顾主、客观因素的组合权重模糊物元评价模型。该模型有效避免了权重分配困难的问题,既能得到综合评价信息,也能反映评价对象的稳定状态。主、客观权重法既利用了样本资料的统计信息,又反映了专家的理论知识和经验,可得到较为客观、合理的指标权重。工程实例分析表明,该方法能准确反映边坡稳定性状况,为边坡稳定性的综合评价提供一条新的思路。 相似文献
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场地地震稳定性一直是岩土工程和工程抗震领域非常关注的问题之一，对防灾减灾意义重大。本文提出一套基于ArcGIS评价场地地震稳定性的技术方法，即将ArcGIS与层次分析法相结合，分析处理主要影响场地地震稳定性的因素，最终得出场地地震稳定性区划图。该方法中ArcGIS可将众因素分散的基础数据处理成系统的数字化与可视化的属性数据库和空间数据库，并可在此基础上进行数据运算和等级自动划分；而层次分析法是数据运算的基础，该方法分别对各个因素内部不同区域的特性和各要素之间对场地地震稳定性影响的权重进行定量分析，以便在ArcGIS中进行叠加运算。以唐山地区为例，对上述方法进行了专题论证，得出该地区的场地地震稳定性的等级区划图，划分的区域与地震灾害专家对唐山大地震发生三天后拍摄的航拍片的解译进行对比，结果基本吻合。这验证了本文所用技术方法在分析场地地震稳定性方面的适用性，为我国的防灾减灾计划和国土资源的规划利用提供依据。 相似文献
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P. A. Lozovik 《Water Resources》2013,40(6):631-639
A classification of surface waters of humid zone by its humus content, alkalinity, and trophic status has been developed basing on the acid-base equilibrium of those waters, governed by two systems: humus and carbonate, which enabled the geochemical classes of water to be established more objectively than by expert systems. An integrated estimate of natural water quality is given with the use of quality points by individual characteristics. For water bodies subject to anthropogenic impact, the degree of their pollution is given in accordance with water pollution index, which is calculated by the main standardized components, taking into account their geochemical background level and the values of MAC for water bodies used for fishery. 相似文献
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Shiliang Su Dan Li Xiang Yu Zhonghao Zhang Qi Zhang Rui Xiao Junjun Zhi Jiaping Wu 《Stochastic Environmental Research and Risk Assessment (SERRA)》2011,25(6):737-746
Given the important role of land ecosystem in social-economic progress at regional, national, and international scale and
concurrent degradation of land ecosystems under rapid urbanization, a systematic diagnosis of land ecological security (eco-security)
for sustainable development is needed. A catastrophe model for land ecological security assessment was developed in order
to overcome the disadvantages in subjectivity and complexity of the currently used assessment methods. The catastrophe assessment
index system was divided into hierarchical sub-systems under the pressure-state-response framework. The catastrophe model
integrated multiple assessment indices of land eco-security according to the inherent contradictions and relative importance
of indices without calculating weights. Specifically, membership degree of higher level index was calculated based on the
membership degrees of lower level indices that were subjective to suitable model, such as cusp, fold, swallowtail and butterfly
model. This model was applied to evaluate the state of land eco-security in Shanghai. Mann–Kendall’s test was utilized to
characterize its temporal trend between 1999 and 2008. Significant downward trend was identified for land eco-security, in
terms of pressure sub-index, state sub-index, response sub-index and synthetic index. All these implied that land ecosystem
conditions were not optimistic for Shanghai and such situation should draw the attention of policy makers. The calculation
procedure presented in this paper does not require a high level of technical expertise to determine the membership degree,
making it simple and operational. Being applicable to similar land ecosystems, the catastrophe model is thus believed to provide
an alternative approach to land eco-security assessment. 相似文献
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Concentration and fractionation of trace metals in surface sediments of intertidal Bohai Bay, China 总被引：4，自引：0，他引：4
Surface sediments from intertidal Bohai Bay were sampled for the geochemical and environmental assessment of six trace metals (Cd, Cr, Cu, Ni, Pb and Zn). Results indicate that sediment grain size plays an important role in controlling the distribution and fractionation of them. Metal concentrations in clayey silt sediments are all clearly higher than in sand and silty sand ones. Cd and Pb in clayey silt sediments are more mobile than in sand and silty sand ones. Two sediment quality guidelines and two geochemical normalization methods (index of geoaccumulation and enrichment factor) were used to judge the potential risk and accumulation of metals. According to the mean probable effects level quotient, the combination of studied metals may have a 21% probability of being toxic. The sediments with high fraction of clay and silt have been contaminated by trace metals to various degrees, among which Cr contributes the most to contamination. 相似文献
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Integrative fuzzy set pair model for land ecological security assessment: a case study of Xiaolangdi Reservoir Region, China 总被引：5，自引：1，他引：4
Shiliang Su Xia Chen Stephen D. DeGloria Jiaping Wu 《Stochastic Environmental Research and Risk Assessment (SERRA)》2010,24(5):639-647
Due to the increasingly serious ecological degradation of land systems, the land ecological security issues have attracted
more and more attention of policy makers, researchers and citizens. Aiming at overcoming the disadvantages in subjectivity
and complexity of the currently used assessment methods, an integrative fuzzy set pair model for assessing the land ecological
security was developed by integrating fuzzy assessment and set pair analysis (SPA). The approximate degree of land ecological
security to the optimal standard set was calculated to describe the secure level by combining multiple indices. The indices
and weights were determined by a pressure-state-response model and the fuzzy analytic hierarchy process (AHP), respectively.
Aided by a geographic information system, this model was applied to evaluate comprehensively the status of land ecological
security in Xiaolangdi Reservoir Region, China, taking the administrative division as the assessment unit. The results showed
that 20% of the total area maintained a slightly secure status, while 50% of the study area was of a middle or seriously low
grade of land ecological security. The remaining portion (30%) was the most ecologically insecure. From the spatial prospective,
obvious variations were observed. The land eco-security gradually decreased from the Xiaolangdi Dam to its surrounding regions.
It was concluded that the status of the integral land ecological security of Xiaolangdi Reservoir Region was in the middle
level, and increasingly intense human activities speeded up the degradation of regional land ecosystem in recent years and
thus induced the crisis of land ecological security. 相似文献
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This paper reports the main results of the EC-ProjectSERGISAI. The project developed a computer prototypewhere a methodology for seismic risk assessment hasbeen implemented. Standard procedural codes,Geographic Information Systems and ArtificialIntelligence Techniques compose the prototype, whichpermits a seismic risk assessment to be carried outthrough the necessary steps. Risk is expressed interms of expected damage, given by the combination ofhazard and vulnerability. Two parallel paths have beenfollowed with respect to the hazard factor: theprobabilistic and the deterministic approach. Thefirst provides the hazard analysis based on historicaldata, propagation models, and known seismic sources.The deterministic approach provides the input forscenarios, by selecting a specific ground motion.With respect to the vulnerability factor, severalsystems have been taken into account apart frombuildings, which are usually considered in this typeof analysis. Defining vulnerability as a measure ofhow prone a system is to be damaged in the event of anearthquake, an attempt has been made to move from theassessment of individual objects to the evaluation ofthe performance of urban and regional areas. Anotherstep towards an approach which can better serve civilprotection and land use planning agencies has beenmade by adapting the analysis to the followinggeographical levels: local, sub-regional and regional.Both the hazard and the vulnerability factors havebeen treated in the most suitable way for each one, interms of level of detail, kind of parameters and unitsof measure. In this paper are shown some resultsobtained in two test areas: Toscana in Italy, for theregional level, the Garfagnana sub-area in Toscana,for the sub-regional level, and a part of the city ofBarcelona, Spain, for the local level. 相似文献
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Can global sensitivity analysis steer the implementation of models for environmental assessments and decision-making? 总被引：3，自引：1，他引：3
S. Tarantola N. Giglioli J. Jesinghaus A. Saltelli 《Stochastic Environmental Research and Risk Assessment (SERRA)》2002,16(1):63-76
We illustrate a method of global sensitivity analysis and we test it on a preliminary case study in the field of environmental
assessment to quantify uncertainty importance in poorly-known model parameters and spatially referenced input data. The focus
of the paper is to show how the methodology provides guidance to improve the quality of environmental assessment practices
and decision support systems employed in environmental policy. Global sensitivity analysis, coupled with uncertainty analysis,
is a tool to assess the robustness of decisions, to understand whether the current state of knowledge on input data and parametric
uncertainties is sufficient to enable a decision to be taken. The methodology is applied to a preliminary case study, which
is based on a numerical model that employs GIS-based soil data and expert consultation to evaluate an index that joins environmental
and economic aspects of land depletion. The index is used as a yardstick by decision-makers involved in the planning of highways
to identify the route that minimises the overall impact. 相似文献
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复杂多变的陆地表微波比辐射率,造成陆面上星载微波观测反演大气参数较为困难,也使得许多卫星微波资料不易同化应用到数值模式,因此迫切需要提供准确可靠的陆面微波地表比辐射率信息.随着卫星观测技术的迅速发展,利用丰富的星载被动微波观测直接反演陆面微波比辐射率成为一种主要手段.国外针对星载微波成像仪和微波垂直探测器开展较为系统的陆面微波比辐射率研究,建立不同类型的地表比辐射率反演方法,开发地表比辐射率参数化方法并应用于辐射资料同化.对于卫星观测反演陆面微波比辐射率存在的问题,开展了评估分析和方法订正.国内利用卫星观测也开展了一些陆面微波比辐射率研究工作,尚需要系统、综合的提炼.对于地表特征复杂的中国地区,还需要评估认识不同陆面微波比辐射率反演方法在我国适用情况,需要增强陆面微波比辐射率数据质量的认识以及业务应用. 相似文献