Wenchuan earthquake caused huge casualties and economic losses, The damage to housing construction accounted for a large proportion. In recent years, focus of the study question is how fast and accurate understanding seismic capacity of group building and post-earthquake losses in urban areas. Vulnerability analysis of building structures is an important component of earthquake loss estimation. It has important practical significance for various cities and regions to develop reasonable earthquake disaster mitigation planning and emergency response.
This paper studies the following aspects:
(1) The choice of vulnerability analysis method has significant impact on the results of earthquake loss estimation. Therefore, this paper studies the correlation between seismic peak acceleration and damage indices of sructure from the perspective of the relevance of random variables. A case study of the masonry and frames select different damage indices. Studies have shown that peak ground acceleration values have best correlation with transcendence intensity rate for the masonry and have better correlation with inter-story drift ratio for frames.
(2) This paper studies total probabilistic seismic risk analysis of single and group buildings. The used method that is simple and practical can be used to assess the comprehensive seismic capacity of cities in China. Seismic vulnerability analysis adopts peak ground acceleration as earthquake input and considers the uncertainty of ground motion parameters. Finally the probabilistic results of seismic damage to the structure in design reference period can be acquired. A case study of the masonry with constructional columns verify the accuracy of the method.
(3) This paper focuses on the group vulnerability of buildings and puts forward a new fast evaluation approach of group vulnerability for post-earthquake. Impersonal weight determination by entropy method and similarity theory in fuzzy mathematics are introduced in group vulnerability analysis, which can evaluate earthquake disaster of group buildings rapidly and reliably. Group vulnerability analysis method presented in the paper is applied in masonry and frames. By studying the seismic capacity similarity of typical known monomer and unknown monomer,Further vulnerability result of unknown monomer is obtained by the vulnerability of the typical monomer. Finally the result of group vulnerability can be obtained by statistical analysis.
(4) This paper combines structural vulnerability analysis with performance-based seismic design concept. It can assess the seismic performance of existing buildings.
In addition, the economic losses caused by the earthquake have been studied. A direct economic loss model which considers structure of different uses is proposed. Finally it can obtain the assessment of total cost of structures during the whole life-cycle and provide reference for the application performance-based seismic design.
Article Source: Technology Science Articles Information Technology Articles
4/12/2010
Energy Diversification Pathway of China for Energy Security
The rapid increase in energy consumption has brought issues such as energy supply and demand imbalance, which makes energy security has become an international subject of widespread concern. Environmental pollution and climate change caused by energy use also seriously threat the sustainable economic development. As the world's fast-growing economies, China's energy demand particularly strong. While, China accounted for nearly three-quarters of global energy consumption growth in 2008.
How to ensure energy security has also become China's a great challenge.As an important strategy for energy security, the theoretical significance and practical value of energy diversification have gradually caught scholars and policy-makers' attention. Diversification of energy resources reduces the over-reliance on a single or few energy options through the provision of multiple choices. Since it can reduce the risk of supply disruptions on one hand, and ensure that energy use does not cause irreversible impacts on the environment on the other hand, Energy Diversification is an important means to ensure energy security from the system level.This paper first analyzed the research background and theoretical relevance of this subject, and straightened out the existing research home and abroad, summed up the research trends and weaknesses.
Then, based on defining energy diversification and energy security, used the energy economic theory to systematically analyze the relationship between energy diversification and energy security, then from the point of view of portfolio theory, analyzed diversification the scope of the role of energy security. Next, build the energy security-oriented MDA model of China's energy diversification, using time-series data on energy consumption to dynamic analysis China's diversity and energy security performance of the. Then, analyzed the multiple trades-offs during diversification path selection process. Based on establishment of system performance optimization models in different contexts, establish the optimal combination selection mechanism of China's energy diversification from the system level. Try to explore a diversification path selection method with a combination of resources and socio-economic conditions. Finally, in summing up the study of this paper, gave some policy recommendations for China's energy diversification.
Article source: Information Technology Articles.com/
How to ensure energy security has also become China's a great challenge.As an important strategy for energy security, the theoretical significance and practical value of energy diversification have gradually caught scholars and policy-makers' attention. Diversification of energy resources reduces the over-reliance on a single or few energy options through the provision of multiple choices. Since it can reduce the risk of supply disruptions on one hand, and ensure that energy use does not cause irreversible impacts on the environment on the other hand, Energy Diversification is an important means to ensure energy security from the system level.This paper first analyzed the research background and theoretical relevance of this subject, and straightened out the existing research home and abroad, summed up the research trends and weaknesses.
Then, based on defining energy diversification and energy security, used the energy economic theory to systematically analyze the relationship between energy diversification and energy security, then from the point of view of portfolio theory, analyzed diversification the scope of the role of energy security. Next, build the energy security-oriented MDA model of China's energy diversification, using time-series data on energy consumption to dynamic analysis China's diversity and energy security performance of the. Then, analyzed the multiple trades-offs during diversification path selection process. Based on establishment of system performance optimization models in different contexts, establish the optimal combination selection mechanism of China's energy diversification from the system level. Try to explore a diversification path selection method with a combination of resources and socio-economic conditions. Finally, in summing up the study of this paper, gave some policy recommendations for China's energy diversification.
Article source: Information Technology Articles.com/
The Research of Magnetic Driver Simulation System for Magnetic Pump
The magnetic drive system of the magnetic driver pump is usually composed of inner magnetic rotor、and containment shell. The inner magnetic rotor connect with the being transmissioned parts, and the outer magnetic rotor connect with the transmission parts. Magnetic transmission has the function of Elastic coupling vibration absorption, and to the point, it can completely seal the inner magnetic rotor and the being transmissioned parts. Without the mechanical contact,it also can pass the kinematic and dynamic of the transmission parts to the being transmissioned parts by magnetic action, so that the dynamic seal becomes to static seal.
Therefore, magnetic drive is wildly used in the environment of which has some special demands of seal, such as petroleum, chemical, pharmacy, food and aviation field.During the design and calculating of magnetic drivers, the process "preliminary design—modeling—analysis—revision—re-design—re-modeling—re-analysis"will be carried out repeatedly, and the process are operated complex the requirement to Users is too much, and the user be apt to make mistake during the processing. To solve the problems mentioned above, the study has developed a magnetic driver simulation system. This system contains three parts: parametric design, Parametric modeling and parametric finite element.The study of 3D parametric design system is based on characteristics of the structure of the cylinder typed radial magnetic drive, design flow and design method.
This system Use Solid Works as the supporting platform and take VB language to do the secondary development of the API function of Solid Works. It can realize the auto-modeling and assembling of every parts of the magnetic drive.Based on ANSYS, the study use vector potential method and scalar potential method to build 2D, 3D models of the magnetic field of cylinder typed radial magnetic drive, then do the solution computation and analysis the distribution of magnetic line, the distribution of magnetic induction, the size of the moment of magnetic force and the size of eddy current. A template for magnetic drivers structure calculating and analysis based on ANSYS is built.
The system possesses the following features:
1. A method of parametric finite element analysis for magnetic drivers is presented in this system, the FEA model is droved by the parameters.
2. through proceeding communication mechanism of Windows, the centre of control based on passages is formed. it can be use the ANSYS as a subprogram.The developed magnetic driver simulation system, under the different design parameter, is advantageous for the magnetic driver to rebuild the model fast, and carry on the finite element simulation analysis . The above conclusion and the method have enriched the magnetic driver research contend, and explored a lower consumption higher quality design and analysis method.
Article source from:http://www.latest-science-articles.com/Technology_Science/ and http://information-technology-articles.com/
Therefore, magnetic drive is wildly used in the environment of which has some special demands of seal, such as petroleum, chemical, pharmacy, food and aviation field.During the design and calculating of magnetic drivers, the process "preliminary design—modeling—analysis—revision—re-design—re-modeling—re-analysis"will be carried out repeatedly, and the process are operated complex the requirement to Users is too much, and the user be apt to make mistake during the processing. To solve the problems mentioned above, the study has developed a magnetic driver simulation system. This system contains three parts: parametric design, Parametric modeling and parametric finite element.The study of 3D parametric design system is based on characteristics of the structure of the cylinder typed radial magnetic drive, design flow and design method.
This system Use Solid Works as the supporting platform and take VB language to do the secondary development of the API function of Solid Works. It can realize the auto-modeling and assembling of every parts of the magnetic drive.Based on ANSYS, the study use vector potential method and scalar potential method to build 2D, 3D models of the magnetic field of cylinder typed radial magnetic drive, then do the solution computation and analysis the distribution of magnetic line, the distribution of magnetic induction, the size of the moment of magnetic force and the size of eddy current. A template for magnetic drivers structure calculating and analysis based on ANSYS is built.
The system possesses the following features:
1. A method of parametric finite element analysis for magnetic drivers is presented in this system, the FEA model is droved by the parameters.
2. through proceeding communication mechanism of Windows, the centre of control based on passages is formed. it can be use the ANSYS as a subprogram.The developed magnetic driver simulation system, under the different design parameter, is advantageous for the magnetic driver to rebuild the model fast, and carry on the finite element simulation analysis . The above conclusion and the method have enriched the magnetic driver research contend, and explored a lower consumption higher quality design and analysis method.
Article source from:http://www.latest-science-articles.com/Technology_Science/ and http://information-technology-articles.com/
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