Usually landslide studying investigates the facts such as gender land, atmospheric rainfall, gradients＇ change, earthquake, volcanic eruption, subterranean water vibration, and human causes in the form of different m...Usually landslide studying investigates the facts such as gender land, atmospheric rainfall, gradients＇ change, earthquake, volcanic eruption, subterranean water vibration, and human causes in the form of different models. However, the facts can have main share in appearing this phenomenon but correlative and sufficient condition for genesis and such a phenomenon is historical base of lands＇ bed that has experienced specific formative process. In the case of distribution and dispersion of slides and their reasons of occurring in lsfahan, general studying has also been carried out. And this article has investigated this phenomenon on the other aspects and has tried to reveal this phenomenon＇s effect on instigating instabilities, so that it can conclude distribution of this phenomenon references to climate on one side and historical formative process on the other side. It aims to study this effect by using IDW （Inverse Distance Weighting）, Kiriging method in ArcGIS 9.3 software dispersal map of Isfahan＇s main landslides and formative systems on the other side and by local analyzing these two collections evaluated their vicinity relation using local-statistical ways. Results of this research will show that in the past the main part of this landslide has occurred in cold hole and seldom occurred in hot hole.展开更多
A set of compressed natural gas (CNG) multi-point direct injection system of spark-ignited engines and the corresponding measurement and data acquisition systems were developed in this paper. Based on different inject...A set of compressed natural gas (CNG) multi-point direct injection system of spark-ignited engines and the corresponding measurement and data acquisition systems were developed in this paper. Based on different injection modes, the mixture formation and combustion of CNG low-pressure direct injection (LPDI) engines were studied under varying factors such as air/ fuel ratio, injection timing. Meanwhile, three-dimensional simulations were adopted to explain the mixture formation mechanisms of CNG low-pressure compound direct injection (LPCDI) mode. On the basis of test results and simulation of the mixture homogeneous degree, the conception of injection window was proposed, and the LPCDI mode was proved to be more beneficial to the mixture concentration stratification formation in cylinder under lean-burning conditions, which resulted in effective combustion and stability.展开更多
A method based on the virtual prototype technology simulating the separation of a launch vehicle from its aircraft in the aircraft wake was proposed based on the internally carried air-launched launch vehicle program....A method based on the virtual prototype technology simulating the separation of a launch vehicle from its aircraft in the aircraft wake was proposed based on the internally carried air-launched launch vehicle program.In this method,the full-scale model of the aircraft,the vehicle and the parachute are constructed.Then,they are imported into the ADAMS software,constraint solutions and driving forces are then added for visual dynamic simulation.The unsteady aerodynamic forces of the vehicle in the aircraft wake are calculated by CFD and the moving grid technique.The forces generated by the parachute can be derived from the Kirchhoff motion equation.Through comparing and analyzing the simulation results under different launch conditions,it has been proven that this method simulates the separation of a launch vehicle from the aircraft in the aircraft wake accurately.It provides the foundation for the aggregate project of internally carried air-launch vehicles,and offers a new referenced method for multi-body dynamic simulation.展开更多
文摘Usually landslide studying investigates the facts such as gender land, atmospheric rainfall, gradients＇ change, earthquake, volcanic eruption, subterranean water vibration, and human causes in the form of different models. However, the facts can have main share in appearing this phenomenon but correlative and sufficient condition for genesis and such a phenomenon is historical base of lands＇ bed that has experienced specific formative process. In the case of distribution and dispersion of slides and their reasons of occurring in lsfahan, general studying has also been carried out. And this article has investigated this phenomenon on the other aspects and has tried to reveal this phenomenon＇s effect on instigating instabilities, so that it can conclude distribution of this phenomenon references to climate on one side and historical formative process on the other side. It aims to study this effect by using IDW （Inverse Distance Weighting）, Kiriging method in ArcGIS 9.3 software dispersal map of Isfahan＇s main landslides and formative systems on the other side and by local analyzing these two collections evaluated their vicinity relation using local-statistical ways. Results of this research will show that in the past the main part of this landslide has occurred in cold hole and seldom occurred in hot hole.
基金Supported by National High Technology Research and Development Program ("863" Program) of China (No.2008AA11A114)
文摘A set of compressed natural gas (CNG) multi-point direct injection system of spark-ignited engines and the corresponding measurement and data acquisition systems were developed in this paper. Based on different injection modes, the mixture formation and combustion of CNG low-pressure direct injection (LPDI) engines were studied under varying factors such as air/ fuel ratio, injection timing. Meanwhile, three-dimensional simulations were adopted to explain the mixture formation mechanisms of CNG low-pressure compound direct injection (LPCDI) mode. On the basis of test results and simulation of the mixture homogeneous degree, the conception of injection window was proposed, and the LPCDI mode was proved to be more beneficial to the mixture concentration stratification formation in cylinder under lean-burning conditions, which resulted in effective combustion and stability.
基金Supported by the National Natural Science Foundation Programme of China(No.61374145)
文摘A method based on the virtual prototype technology simulating the separation of a launch vehicle from its aircraft in the aircraft wake was proposed based on the internally carried air-launched launch vehicle program.In this method,the full-scale model of the aircraft,the vehicle and the parachute are constructed.Then,they are imported into the ADAMS software,constraint solutions and driving forces are then added for visual dynamic simulation.The unsteady aerodynamic forces of the vehicle in the aircraft wake are calculated by CFD and the moving grid technique.The forces generated by the parachute can be derived from the Kirchhoff motion equation.Through comparing and analyzing the simulation results under different launch conditions,it has been proven that this method simulates the separation of a launch vehicle from the aircraft in the aircraft wake accurately.It provides the foundation for the aggregate project of internally carried air-launch vehicles,and offers a new referenced method for multi-body dynamic simulation.
