Estimation method of building damage level was introduced for the accurate and effective estimation of damage extent and relief goods demand according to long-distance image contrast. In order to obtain completion deg...Estimation method of building damage level was introduced for the accurate and effective estimation of damage extent and relief goods demand according to long-distance image contrast. In order to obtain completion degree of building edge extracted from long-distance images before and after disaster, the concentration ratio was analyzed with Hough transformation. Based on the maximum posterior probability, estimation method of affected population was designed to accurately estimate victim population, which can be directly reflected by fugitive population. Moreover, on basis of escape route and fugitive population, demand assignment algorithm by backward calculation was designed to improve rescue efficiency.展开更多
Linear rolling guideways(LRGs) play an important role in precision engineering. In the pre-rolling region, the hysteretic friction force exerts great impacts on the positioning accuracy. Numerical and experimental stu...Linear rolling guideways(LRGs) play an important role in precision engineering. In the pre-rolling region, the hysteretic friction force exerts great impacts on the positioning accuracy. Numerical and experimental studies of the hysteresis of friction force are presented in this paper. A model, which is based on the stripe theory and the simplified theory of rolling contact, is built to describe the transient hysteresis of the friction force. Then, the model is modified by taking the anelasticity effect into consideration. Experimentally, a linear motor direct-drive setup is utilized to measure the transient asymmetrical hysteresis of the friction force in the pre-rolling region of an LRG. The influences of the pre-rolling displacement and the dwelling time on the asymmetrical hysteresis of the friction force are studied. The numerical and experimental results are well correlated, which shows good accuracy of the model. The transient asymmetrical hysteresis of friction force in the pre-rolling region of LRGs can thus be determined using the model.展开更多
To study the relationship between under-urbanization and international trade, we set up a model of the transfer of surplus rural labor in an open economy using 1995-2010 data from 40 countries and regions where indust...To study the relationship between under-urbanization and international trade, we set up a model of the transfer of surplus rural labor in an open economy using 1995-2010 data from 40 countries and regions where industrialization was incomplete. Our findings indicate that if, in an open economy, there is a substantial labor surplus and in which domestic goods and services can be sold to foreign markets, there will be a significantly positive correlation between the net export ratio and the degree to which urbanization lags behind industrialization; countries or regions with higher marketization level, lower urban unemployment rate and poorer public health facilities are more likely to be under- urbanized; and an inverted U-shaped relationship exists between under-urbanization and percapita GDR展开更多
文摘Estimation method of building damage level was introduced for the accurate and effective estimation of damage extent and relief goods demand according to long-distance image contrast. In order to obtain completion degree of building edge extracted from long-distance images before and after disaster, the concentration ratio was analyzed with Hough transformation. Based on the maximum posterior probability, estimation method of affected population was designed to accurately estimate victim population, which can be directly reflected by fugitive population. Moreover, on basis of escape route and fugitive population, demand assignment algorithm by backward calculation was designed to improve rescue efficiency.
文摘Linear rolling guideways(LRGs) play an important role in precision engineering. In the pre-rolling region, the hysteretic friction force exerts great impacts on the positioning accuracy. Numerical and experimental studies of the hysteresis of friction force are presented in this paper. A model, which is based on the stripe theory and the simplified theory of rolling contact, is built to describe the transient hysteresis of the friction force. Then, the model is modified by taking the anelasticity effect into consideration. Experimentally, a linear motor direct-drive setup is utilized to measure the transient asymmetrical hysteresis of the friction force in the pre-rolling region of an LRG. The influences of the pre-rolling displacement and the dwelling time on the asymmetrical hysteresis of the friction force are studied. The numerical and experimental results are well correlated, which shows good accuracy of the model. The transient asymmetrical hysteresis of friction force in the pre-rolling region of LRGs can thus be determined using the model.
基金a research product of the CASS Innovation Project "Urbanization,Structural Effects and China's Economic Growth Model"
文摘To study the relationship between under-urbanization and international trade, we set up a model of the transfer of surplus rural labor in an open economy using 1995-2010 data from 40 countries and regions where industrialization was incomplete. Our findings indicate that if, in an open economy, there is a substantial labor surplus and in which domestic goods and services can be sold to foreign markets, there will be a significantly positive correlation between the net export ratio and the degree to which urbanization lags behind industrialization; countries or regions with higher marketization level, lower urban unemployment rate and poorer public health facilities are more likely to be under- urbanized; and an inverted U-shaped relationship exists between under-urbanization and percapita GDR
