针对虚拟手术中缝合线打结仿真时存在的实时性、逼真度较差等问题,采用质点弹簧系统(Mass Spring System,MSS)方法建模,并结合物体非线性及弯曲特性对其进行受力分析。采用Verlet法数值求解模型动力学方程,并基于跟踪控制点方法实现缝...针对虚拟手术中缝合线打结仿真时存在的实时性、逼真度较差等问题,采用质点弹簧系统(Mass Spring System,MSS)方法建模,并结合物体非线性及弯曲特性对其进行受力分析。采用Verlet法数值求解模型动力学方程,并基于跟踪控制点方法实现缝合线运动模拟。提出一种基于层次包围球的模拟受力方法解决缝合线打结过程中的自碰撞检测与响应。仿真结果表明,跟踪控制点方法能有效地完成缝合线的动态仿真,并且通过模拟受力方法能够实现缝合线的打结操作,增加了缝合线运动模拟的逼真度和实时性,提高了仿真效率。展开更多
We report on a polarization-adjustable picosecond deep-ultraviolet (DUV) laser at 177.3 nm.The DUV laser was produced by second harmonic generation from a mode-locked laser at 355 nm in nonlinear optical crystal KBBF....We report on a polarization-adjustable picosecond deep-ultraviolet (DUV) laser at 177.3 nm.The DUV laser was produced by second harmonic generation from a mode-locked laser at 355 nm in nonlinear optical crystal KBBF.The laser delivered a maximum average output power of 1.1 m W at 177.3 nm.The polarization of the 177.3nm beam was adjusted with linear and circular polarization by means of λ/4 and λ/2 wave plates.To the best of our knowledge,the laser has been employed as the circularly polarized and linearly polarized DUV light source for a spin- and angle-resolved photoemission spectroscopy with high resolution for the first time.展开更多
文摘针对虚拟手术中缝合线打结仿真时存在的实时性、逼真度较差等问题,采用质点弹簧系统(Mass Spring System,MSS)方法建模,并结合物体非线性及弯曲特性对其进行受力分析。采用Verlet法数值求解模型动力学方程,并基于跟踪控制点方法实现缝合线运动模拟。提出一种基于层次包围球的模拟受力方法解决缝合线打结过程中的自碰撞检测与响应。仿真结果表明,跟踪控制点方法能有效地完成缝合线的动态仿真,并且通过模拟受力方法能够实现缝合线的打结操作,增加了缝合线运动模拟的逼真度和实时性,提高了仿真效率。
基金Supported by the National Basic Research Program of China under Grant No 2010CB630706the National High-Technology Research and Development Program of Chinathe National Natural Science Foundation of China,and the Knowledge Innovation Program of Chinese Academy of Sciences.
文摘We report on a polarization-adjustable picosecond deep-ultraviolet (DUV) laser at 177.3 nm.The DUV laser was produced by second harmonic generation from a mode-locked laser at 355 nm in nonlinear optical crystal KBBF.The laser delivered a maximum average output power of 1.1 m W at 177.3 nm.The polarization of the 177.3nm beam was adjusted with linear and circular polarization by means of λ/4 and λ/2 wave plates.To the best of our knowledge,the laser has been employed as the circularly polarized and linearly polarized DUV light source for a spin- and angle-resolved photoemission spectroscopy with high resolution for the first time.