雷达散射截面RCS(R adar C ross Section)是基于平面波照射下目标各项同性散射的概念。飞行器RCS的仿真建模在飞行器的仿真过程中既是重点,也是难点。结合雷达模拟器研制过程中对飞行器雷达散射截面仿真建模的实际需求,在建立简化飞行...雷达散射截面RCS(R adar C ross Section)是基于平面波照射下目标各项同性散射的概念。飞行器RCS的仿真建模在飞行器的仿真过程中既是重点,也是难点。结合雷达模拟器研制过程中对飞行器雷达散射截面仿真建模的实际需求,在建立简化飞行器外形模型和六自由度运动姿态计算的基础上根据目标外形建模特点,将飞行器分解为机头、机身、机翼三种类型的散射体进行研究。针对各类部件的不同特性,综合运用了几何光学法、物理光学法和绕射理论计算飞行器RCS。这种理论建模方法简单,物理概念清晰,计算量不大,能满足仿真实时性要求。展开更多
This paper proposes a dynamic model to forecast intraday volume percentages by decomposing the trade volume into two parts: The average part as the intraday volume pattern and the residual term as the abnormal changes...This paper proposes a dynamic model to forecast intraday volume percentages by decomposing the trade volume into two parts: The average part as the intraday volume pattern and the residual term as the abnormal changes. An empirical test on data spanning half-a-year gold futures and S&P 500 futures reveals that a rolling average of the previous days' volume percentages shows great predictive ability for the average part. An SVM approach with the input pattern consisting of two categories is employed to forecast the residual term. One is the previous days' volume percentages in the same time interval and the other is the most recent volume percentages. The study shows that this dynamic SVM-based forecasting approach outperforms the other commonly used statistical methods and enhances the tracking performance of a VWAP strategy greatly.展开更多
Y2001-62863-536 0120786含尘等离子体中的固有电子密度波动=Intrinsic elec-tron density fluctuation in a plasma with dust[会,英]/Li,F.//2000 5th International Symposium on Anten-nas,Propagation and EM Theory Proceedings....Y2001-62863-536 0120786含尘等离子体中的固有电子密度波动=Intrinsic elec-tron density fluctuation in a plasma with dust[会,英]/Li,F.//2000 5th International Symposium on Anten-nas,Propagation and EM Theory Proceedings.—536～539(PC)展开更多
文摘雷达散射截面RCS(R adar C ross Section)是基于平面波照射下目标各项同性散射的概念。飞行器RCS的仿真建模在飞行器的仿真过程中既是重点,也是难点。结合雷达模拟器研制过程中对飞行器雷达散射截面仿真建模的实际需求,在建立简化飞行器外形模型和六自由度运动姿态计算的基础上根据目标外形建模特点,将飞行器分解为机头、机身、机翼三种类型的散射体进行研究。针对各类部件的不同特性,综合运用了几何光学法、物理光学法和绕射理论计算飞行器RCS。这种理论建模方法简单,物理概念清晰,计算量不大,能满足仿真实时性要求。
文摘This paper proposes a dynamic model to forecast intraday volume percentages by decomposing the trade volume into two parts: The average part as the intraday volume pattern and the residual term as the abnormal changes. An empirical test on data spanning half-a-year gold futures and S&P 500 futures reveals that a rolling average of the previous days' volume percentages shows great predictive ability for the average part. An SVM approach with the input pattern consisting of two categories is employed to forecast the residual term. One is the previous days' volume percentages in the same time interval and the other is the most recent volume percentages. The study shows that this dynamic SVM-based forecasting approach outperforms the other commonly used statistical methods and enhances the tracking performance of a VWAP strategy greatly.
文摘Y2001-62863-536 0120786含尘等离子体中的固有电子密度波动=Intrinsic elec-tron density fluctuation in a plasma with dust[会,英]/Li,F.//2000 5th International Symposium on Anten-nas,Propagation and EM Theory Proceedings.—536～539(PC)
