With China's rapid economic development,it is important to formulate reasonable and feasible tax and fee policies to promote the development and utilization of low-grade oil and gas resources to guarantee China's en...With China's rapid economic development,it is important to formulate reasonable and feasible tax and fee policies to promote the development and utilization of low-grade oil and gas resources to guarantee China's energy supply security.In this paper,by analyzing major problems of China's current tax and fee policies for oil and gas resources,a reform program for low-grade oil and gas resources is designed from the aspects of tax/fee items and tax/fee rates.The impacts of this reform program on China and China's oil companies during the "Twelfth Five-Year Plan" are investigated according to the related data in 2008.The results show that the proposed tax and fee reform program will lower the tax burden of oil companies,promote the development of low-grade oil and gas resources,and increase China's GDP and national fiscal revenue.Besides that,it will bring positive social effects by increasing employment opportunities.展开更多
In order to measure the parameters of flight rocket by using radar,rocket impact point was estimated accurately for rocket trajectory correction.The Kalman filter with adaptive filter gain matrix was adopted.According...In order to measure the parameters of flight rocket by using radar,rocket impact point was estimated accurately for rocket trajectory correction.The Kalman filter with adaptive filter gain matrix was adopted.According to the particle trajectory model,the adaptive Kalman filter trajectory model was constructed for removing and filtering the outliers of the parameters during a section of flight detected by three-dimensional data radar and the rocket impact point was extrapolated.The results of numerical simulation show that the outliers and noise in trajectory measurement signal can be removed effectively by using the adaptive Kalman filter and the filter variance can converge in a short period of time.Based on the relation of filtering time and impact point estimation error,choosing the filtering time of 8-10 scan get the minimum estimation error of impact point.展开更多
Under single-satellite observation,the parameter estimation of the boost phase of high-precision space noncooperative targets requires prior information.To improve the accuracy without prior information,we propose a p...Under single-satellite observation,the parameter estimation of the boost phase of high-precision space noncooperative targets requires prior information.To improve the accuracy without prior information,we propose a parameter estimation model of the boost phase based on trajectory plane parametric cutting.The use of the plane passing through the geo-center and the cutting sequence line of sight(LOS)generates the trajectory-cutting plane.With the coefficient of the trajectory cutting plane directly used as the parameter to be estimated,a motion parameter estimation model in space non-cooperative targets is established,and the Gauss-Newton iteration method is used to solve the flight parameters.The experimental results show that the estimation algorithm proposed in this paper weakly relies on prior information and has higher estimation accuracy,providing a practical new idea and method for the parameter estimation of space non-cooperative targets under single-satellite warning.展开更多
基金the National Natural Science Foundation of China(No.70941021)
文摘With China's rapid economic development,it is important to formulate reasonable and feasible tax and fee policies to promote the development and utilization of low-grade oil and gas resources to guarantee China's energy supply security.In this paper,by analyzing major problems of China's current tax and fee policies for oil and gas resources,a reform program for low-grade oil and gas resources is designed from the aspects of tax/fee items and tax/fee rates.The impacts of this reform program on China and China's oil companies during the "Twelfth Five-Year Plan" are investigated according to the related data in 2008.The results show that the proposed tax and fee reform program will lower the tax burden of oil companies,promote the development of low-grade oil and gas resources,and increase China's GDP and national fiscal revenue.Besides that,it will bring positive social effects by increasing employment opportunities.
文摘In order to measure the parameters of flight rocket by using radar,rocket impact point was estimated accurately for rocket trajectory correction.The Kalman filter with adaptive filter gain matrix was adopted.According to the particle trajectory model,the adaptive Kalman filter trajectory model was constructed for removing and filtering the outliers of the parameters during a section of flight detected by three-dimensional data radar and the rocket impact point was extrapolated.The results of numerical simulation show that the outliers and noise in trajectory measurement signal can be removed effectively by using the adaptive Kalman filter and the filter variance can converge in a short period of time.Based on the relation of filtering time and impact point estimation error,choosing the filtering time of 8-10 scan get the minimum estimation error of impact point.
基金supported in part by the National Natural Science Foundation of China(Nos.42271448,41701531)the Key Laboratory of Land Satellite Remote Sensing Application,Ministry of Natural Resources of the People’s Republic of China(No.KLSMNRG202317)。
文摘Under single-satellite observation,the parameter estimation of the boost phase of high-precision space noncooperative targets requires prior information.To improve the accuracy without prior information,we propose a parameter estimation model of the boost phase based on trajectory plane parametric cutting.The use of the plane passing through the geo-center and the cutting sequence line of sight(LOS)generates the trajectory-cutting plane.With the coefficient of the trajectory cutting plane directly used as the parameter to be estimated,a motion parameter estimation model in space non-cooperative targets is established,and the Gauss-Newton iteration method is used to solve the flight parameters.The experimental results show that the estimation algorithm proposed in this paper weakly relies on prior information and has higher estimation accuracy,providing a practical new idea and method for the parameter estimation of space non-cooperative targets under single-satellite warning.