We present a brief overview of follow-up observations of GRB afterglows made by the 0.8-m TNT and other telescopes at the Xinglong observatory during the last three years.Our system,dedicated to the measurement of ear...We present a brief overview of follow-up observations of GRB afterglows made by the 0.8-m TNT and other telescopes at the Xinglong observatory during the last three years.Our system,dedicated to the measurement of early-time optical afterglow emission,responded to 50 GRBs from Jan.2006 to Apr.2009.Among them,about 50% have been successfully detected.The fastest response time is 76 sec(GRB 061110A and GRB 090426) after the space-borne GRB detector was triggered.The redshift distribution spans the range from z = 0.033(GRB 060218) to z = 5.6(GRB 060927).We also report the optical photometric follow-up of GRB 080330,which is an X-ray flash,as an example of our observations.展开更多
An efficient and real-time simulation method is proposed for the dynamic electromagnetic characteristics of cluster targets to meet the requirements of engineering practical applications.First,the coordinate transform...An efficient and real-time simulation method is proposed for the dynamic electromagnetic characteristics of cluster targets to meet the requirements of engineering practical applications.First,the coordinate transformation method is used to establish a geometric model of the observation scene,which is described by the azimuth angles and elevation angles of the radar in the target reference frame and the attitude angles of the target in the radar reference frame.Then,an approach for dynamic electromagnetic scattering simulation is proposed.Finally,a fast-computing method based on sparsity in the time domain,space domain,and frequency domain is proposed.The method analyzes the sparsity-based dynamic scattering characteristic of the typical cluster targets.The error between the sparsity-based method and the benchmark is small,proving the effectiveness of the proposed method.展开更多
目的:"某飞行模拟器训练系统"是一个典型的针对第三代军机、运用现代先进技术研制的全任务仿真系统。以该系统为背景,基于先进的虚拟现实和视景仿真软件-Vega和Mu ltiGen C reator,设计与开发了视景仿真系统。方法:分析了三...目的:"某飞行模拟器训练系统"是一个典型的针对第三代军机、运用现代先进技术研制的全任务仿真系统。以该系统为背景,基于先进的虚拟现实和视景仿真软件-Vega和Mu ltiGen C reator,设计与开发了视景仿真系统。方法:分析了三维视景仿真的系统结构,采用Mu ltiGen C reator进行三维场景建模,通过Vega实现了模型的驱动。结果:建立了既有丰富的场景,又能很好地满足虚拟环境真实沉浸感要求的视景系统。结论:建立的飞行模拟器视景系统能够满足飞行训练的要求。展开更多
基金supported by the National Basic Research Program of China (Grant No. 2009CB824800)the National Natural Science Foundation of China (Grant Nos. 10673014 and 10803008)
文摘We present a brief overview of follow-up observations of GRB afterglows made by the 0.8-m TNT and other telescopes at the Xinglong observatory during the last three years.Our system,dedicated to the measurement of early-time optical afterglow emission,responded to 50 GRBs from Jan.2006 to Apr.2009.Among them,about 50% have been successfully detected.The fastest response time is 76 sec(GRB 061110A and GRB 090426) after the space-borne GRB detector was triggered.The redshift distribution spans the range from z = 0.033(GRB 060218) to z = 5.6(GRB 060927).We also report the optical photometric follow-up of GRB 080330,which is an X-ray flash,as an example of our observations.
文摘An efficient and real-time simulation method is proposed for the dynamic electromagnetic characteristics of cluster targets to meet the requirements of engineering practical applications.First,the coordinate transformation method is used to establish a geometric model of the observation scene,which is described by the azimuth angles and elevation angles of the radar in the target reference frame and the attitude angles of the target in the radar reference frame.Then,an approach for dynamic electromagnetic scattering simulation is proposed.Finally,a fast-computing method based on sparsity in the time domain,space domain,and frequency domain is proposed.The method analyzes the sparsity-based dynamic scattering characteristic of the typical cluster targets.The error between the sparsity-based method and the benchmark is small,proving the effectiveness of the proposed method.
文摘目的:"某飞行模拟器训练系统"是一个典型的针对第三代军机、运用现代先进技术研制的全任务仿真系统。以该系统为背景,基于先进的虚拟现实和视景仿真软件-Vega和Mu ltiGen C reator,设计与开发了视景仿真系统。方法:分析了三维视景仿真的系统结构,采用Mu ltiGen C reator进行三维场景建模,通过Vega实现了模型的驱动。结果:建立了既有丰富的场景,又能很好地满足虚拟环境真实沉浸感要求的视景系统。结论:建立的飞行模拟器视景系统能够满足飞行训练的要求。
