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21.
In this paper, a methodology is suggested and tested for evaluating the relative performance of conventional and adaptive pushover methods for seismic response assessment. The basis of the evaluation procedure is a quantitative measure for the difference in response between these methods and inelastic dynamic analysis which is deemed to be the most accurate. Various structural levels of evaluation and different incremental representations for dynamic analysis are also suggested. This method is applied on a set of eight different reinforced concrete structural systems subjected to various strong motion records. Sample results are presented and discussed while the full results are presented alongside conclusions and recommendations, in a companion paper.  相似文献   
22.
医院可达性评价与规划——以江苏省仪征市为例   总被引:5,自引:0,他引:5  
医院作为公共服务设施的一个重要组成部分,为居民提供了必不可少的医疗机会,其空间分布以及可达性的优劣,直接影响到居民能接触到医院的机会和方便程度。把可达性的概念引入到医院规划中,利用Mapinfo公司的控件MapX和Borland公司的可视化编程语言Delphi,开发了基于时间最短的路径选择信息系统,生成了医院可达性的等时线图和医院服务范围图,通过该系统可直观的看到区域内任何一点到达同一级医院所花费的最短时间以及通过的路径。以江苏省仪征市的医院为例,运用该系统对医院的可达性进行了评价,并提出了医院的规划方案。  相似文献   
23.
结构稳定性是评估文物安全的重要方面。三星堆二号坑出土1号青铜树体量庞大、结构复杂,且存在腐蚀、裂纹等危险因素,为了充分记录、评估其保存状况,本研究在原始几何形状和内部构造的基础上,利用三维数字建模技术,建立其几何模型和数值模型,并估算出青铜神树的质量分布和质心位置等无法实地测量的数据,并使用有限元方法,从应力和位移的角度分析青铜树的静置状态下的安全性。经过有限元模拟和材料力学简化计算,发现龙身和树干连接处、树枝根部应力较大,是易受损区域。  相似文献   
24.
申玉铭  张云 《人文地理》2006,21(3):19-23,103
基于城市化与生态化两大子系统,从人口与空间城市化、经济城市化、社会城市化、和生态环境水平、生态压力、生态抗逆能力六个层面,构建生态城市建设能力评价的指标体系,运用相关分析、回归分析和主成分分析等方法,对1991-2002年北京市生态城市建设能力机理进行了综合分析与评价。  相似文献   
25.
代戈资 《攀登》2007,26(4):88-89
本文以对青海经济有较大影响的18个工业行业为分析基点,运用多元统计中的因子分析方法,从定量和定性分析相结合的角度对青海工业行业的总体规模、企业内部生产管理能力、经济效益、财务风险等进行了综合分析,并在此基础上提出对策建议。  相似文献   
26.
Since the collapse of the communist system, regional inequalities have increased in Central European Countries. This paper describes an assessment of the impacts of regional development programmes on the development of Hungarian regions at a highly disaggregated level between 2002 and 2008. We construct a multi-dimensional composite indicator to estimate the overall development of rural regions and capture social, economic and environmental dimensions. The impacts of rural development programmes were investigated through counterfactual analysis in combination with Propensity Score Matching and Difference-in-Differences approaches. There has been considerable variation with increasing concentration in the level of subsidies distributed during the analysed period. From a policy perspective, the results are disappointing. Irrespective of the subsidy measures or methodology employed, the impact of the former is very close to zero or non-significant. Our findings cast serious doubt on the effectiveness of development policy and the long-run convergence of European regions.  相似文献   
27.
Past earthquakes have demonstrated that historical vaulted adobe buildings are highly vulnerable to seismic actions. Hence, it is crucial for such building typologies to be evaluated in terms of seismic capacity. To this end, this article deals with the seismic performance of historical vaulted adobe houses from the city of Yazd, Iran as one of the seismically active areas of the world and possessing a very rich adobe heritage. Thus, and based on a detailed geometrical survey, a representative sample of adobe houses from Yazd was studied using a simplified in-plane analysis based on three geometric indexes. Concerning the out-of-plane behavior, a deeper assessment was conducted by performing a numerical study, where the main influential parameters on the seismic behavior of vaulted adobe buildings were considered. The numerical analyses were carried out by adopting the limit analysis theory implemented in the Block2D software. The results obtained indicate the safe in-plane behavior of most of the houses and the safe out-of-plane response of the sample under gravitational loads. However, the sample out-of-plane safety under earthquake-induced loads seems to be a matter of concern.  相似文献   
28.
ABSTRACT

Maniace Castle, built on Ortygia island in Siracusa (Italy) in the first half of the 13th century and hosting a magnificent hypostyle hall (the Salone), a square area covered by 25 cross vaults supported by columns, was severely damaged by the 1693 earthquake and the explosion of the ammunition dump in 1704. The buttresses, built immediately afterward to counteract the thrust of the 10 surviving vaults, did not guarantee adequate seismic safety so that a metal scaffolding was installed in 2001 to prevent an overturning mechanism. This article discusses the design and execution of an external pre-stressing steel system to increase existing buttress strength and the seismic capacity of the Salone, starting with historical and constructional analyses and dealing with both analytical and technical aspects. The monitoring system installed to detect structural response during and after the working execution is shown, along with some of the data acquired so far.  相似文献   
29.
ABSTRACT

Building survey is an essential data-collection procedure to feed large-scale seismic vulnerability assessment. The available strategies usually consider survey forms to gather information about the urban buildings. The application of the available survey forms poses important challenges for the case of the heterogeneous urban centers including different structural typologies. This work proposes four specific survey forms for traditional structural typologies constructed with masonry, reinforced concrete, mixed steel-reinforced concrete, and timber. The proposed forms request essential information on the parameters necessary for seismic vulnerability assessment, by evaluating the lateral-load resistant system, regularity, condition of conservation, and existing damages. The survey forms were applied to the study of 111 buildings of the historical center of Valparaíso, Chile. The proposed methodology was complemented with the use of Geographic Information Systems to obtain a complete database with the structural characterization of the most representative typologies for future works of large-scale seismic vulnerability assessment.  相似文献   
30.
Environmentally Sensitive Areas (ESAs) designated under EC Structure Regulation 797/85 now cover 1.4 million ha of the Scottish countryside and are likely to make a substantial contribution to the regulation of landscape change. Visual changes to landscapes with (policy on) and without (policy off) the ESA programme in two Scottish ESA areas, Breadalbane and the Machair, are predicted through impact-assessment procedures and computer manipulation of photographic images. The methodological requirements for such predictions are outlined and substantial differences in landscape characteristics under policy on/off scenarios are revealed. Such approaches to landscape change are an essential foundation for the development of environmental cost-benefit analyses and will contribute to public consultation processes.  相似文献   
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