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911.
建筑物沉降观测结束之后,为降低和预防因地基不均匀沉降等因素造成的不安全事故发生率,准确预测建筑物沉降量变化趋势已引起相关科研单位的重视。首先,将人工神经网络数据分析与灰色GM(1,1)模型相结合,提出GM-ANN预测模型。然后,结合工程实例验证模型对监测沉降危险点数据变化的准确性,形成Matlab拟合曲线和预测趋势图。最终,结果表明仅考虑时间因素,GM-ANN模型明显优于灰色GM(1,1)模型,可使预测精度提高将近三倍。因此,利用GM-ANN预测模型可以对建筑物安全性进行有效预测。  相似文献   
912.
以深圳市高层建筑为研究实例,介绍了香港大学的城市灾害损失评估及应急反应管理系统,并采用此系统内置的建筑易损性分析模块,结合泛珠三角地区灾害危险性概率模式,场地特征及高层建筑实地调查分析结果,从建筑安全性角度对深圳市的标志性建筑进行危险性分析,进而对深圳市应对突发性灾难事件的管理建设提出建议。作为应用实例,模拟一定概率条件下的灾难事件发生时的建筑物损坏情况,归纳出高层建筑的损坏模式,总结深圳市高层建筑的安全性隐患,提出目前防灾减灾急需实施的相应步骤:建议在一元化的城市灾害预警和应急指挥体系下,整合各个灾种防灾减灾管理部门的资源,以科学分析软件为灾情模拟和决策预案制定的工具,使危机处理的理念由领导决策型转向科学分析型,加强城市应对面对突发事件的能力,保障经济与社会的持续稳定发展。  相似文献   
913.
《Environmental Hazards》2013,12(2):112-131
The disaster management applications of geographical information systems and remote sensing are examined relative to the disaster cycle, in pre-disaster, crisis and post-disaster contexts. We focus on the uses and limitations of free or low-cost data and software. A wide range of geospatial datasets are currently freely available, from digital elevation models (DEMs) and thematic digital maps, to multispectral satellite imagery and virtual globes, such as Bing Maps. Maps of hazardous terrain and vulnerable features can be derived from sets of satellite data such as shuttle radar topography mission DEMs and Landsat imagery. The derived maps are particularly useful for district scale (1:25 to 1:100 K) disaster management in low-income countries. Detailed maps (i.e. better than 1:25 K scale) of hazardous terrain and vulnerable features generally require expensive high-resolution satellite imagery or aerial photography.

Although the Internet allows the distribution of free or low-cost geospatial data, software and training materials, there are still some countries with limited Internet access. Data integration, spatial/temporal analysis and map production are also limited by the frequently high price of geoinformatic software, making it a priority to develop suitable Free and Open-Source Software.  相似文献   
914.
《Environmental Hazards》2013,12(1):53-58
In 1984 the Mitigation Implementation Conference recognized the need for effective management of urban development in terms of building standards and land-use zonation. In the intervening 25 years, significant progress has been made in the development of building codes and hazard mapping for disaster risk reduction; however, the failure to promulgate, implement and enforce regulation of development has resulted in the dramatic expansion of exposure and risk. It is now necessary to re-assess regulatory policy and practice. New approaches to regulatory compliance must be explored, including participatory regulation and reliance on cultural and religious bases for individual commitment to community safety.  相似文献   
915.
Traditional Central Himalaya societies face a range of socio-economic and environmental problems. The potential of science and technology has not yet been adequately and appropriately harnessed to overcome the development constraints posed by the fragile Himalayan environment. Thus there is a need for large-scale establishment of technology resource centers. The Garhwal Unit of GB Pant Institute of Himalayan Environment and Development established rural technology demonstration and training centers in three different agroecological zones between 550 and 2200 m asl and in 13–15 locations, with suitable technologies based on appropriate use and management of locally available bio-resources that ensure people participation. About 35 on-site training courses were organised for about 2329 participants. The participants were given on-site demonstrations, training and technical know-how on various technologies, to enable farmers to better understand problems faced during implementation of new technologies for sustainable management of natural resources. An action research framework and training manuals were also developed in consideration of local socio-economic condition. The documentation and analysis of research (quantitative and qualitative) and data related to cost–benefit analysis of the technologies adopted by farmers generated through this study has created wider sharing of farmer training outputs, at farm level, amongst the scientific communities and with policy planners.  相似文献   
916.
This paper presents the results of research on the utilization of slag produced as the waste material of metallic magnesium production. This material is a fine powder with a high magnesium content. The characterization of slag was performed by XRD, DTA and TG analysis. Chemical composition and mechanical properties of slag were also determined. By using a mixture this slag and limestone aggregate, it is possible to obtain dry mortar which, mixed with water, gives a material fully satisfying for plastering mortar. By adding inorganic pigments (Fe2O3, Ca2O3, etc.) decorative mortars are obtained, and when they are spread over the foundation made of brick or concrete, they retain their colour on the entire coating and surface of the mortar.  相似文献   
917.
电石渣脱硫浆液中存在沉降速率低于二水硫酸钙的黑色悬浮物质,严重影响脱硫石膏真空过滤,在浆液沉降装置中,对动态沉降分离电石渣脱硫浆液中的黑色悬浮物质进行了实验研究,研究表明:搅拌转速在30~70 r/min,可实现电石渣脱硫浆液动态沉降分层,搅拌转速为60 r/min时,浆液分层最佳;虹吸分离上层黑色悬浮液,黑色物质去除率可达到70%,在相同的过滤工艺条件下,浆液过滤后滤饼含水率可降低3%~5%;浆液中黑色物质含量低于3 g/L时,进一步降低浆液中黑色物质的含量,对提高浆液脱水性能作用不大,甚至可以忽略不计。  相似文献   
918.
With the beginning of the new millennium, the longstanding need for reform of the United Nations system has gained new momentum. Efficiency gains and better coordination are desirable, though not sufficient to bring about improvement in international relations. There is need, therefore, to look for institutional innovations that would upgrade the pressing tasks of environmental and development policy in the eyes of national governments, international organizations, and non-governmental organizations, improve the institutional setting for the negotiation and implementation of new agreements and action programs, and strengthen the action capacity of the developing countries on these matters. The present article points to and elaborates on the need for a World Environment and Development Organization within the United Nations system, and outlines the shape it might be given.  相似文献   
919.
The diversity of shelters used in transitional settlements for internally displaced persons (IDPs) in Herat, Afghanistan is described. The information is based on a field survey undertaken in March 2002 and highlights the adaptation techniques, which IDPs undertake to improve any provided shelter. Potential areas for improvement are indicated; for example, the possibility for using insulated, demountable liners to prevent cold-related deaths without sacrificing shelter flexibility along with the likely need for better agency coordination of the shelter responses they provide. The wider context in which the technical recommendations would be implemented must also be considered. Such issues include agency resources, political impediments to providing the desired option, and the preference of many IDPs that the best shelter would be their home.  相似文献   
920.
本文提出了在沿海地区滨海相地层中深井降水的设计方法,深刻剖析了影响降水的诸多因素,并结合九州大厦工程实例加以验证,为类似工程提供了可借鉴的方法。  相似文献   
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