为实现完整熔池表面形貌三维传感,构建了双棱镜单摄像机立体视觉传感系统.针对熔池图像纹理缺乏造成的立体匹配困难的问题,引入了全局优化的变分立体匹配算法,通过建立包含灰度差异数据项和空间连续性约束项的能量函数的可行性泛函,经...为实现完整熔池表面形貌三维传感,构建了双棱镜单摄像机立体视觉传感系统.针对熔池图像纹理缺乏造成的立体匹配困难的问题,引入了全局优化的变分立体匹配算法,通过建立包含灰度差异数据项和空间连续性约束项的能量函数的可行性泛函,经过迭代求解获得具有丰富细节的熔池表面稠密视差图.对自制非标准凹面形状进行立体匹配和三维重建,结果表明,宽度误差小于3.16%,深度误差小于4.82%.基于该算法实现了熔化极气体保护焊(gas metal arc welding,GMAW)的堆焊及V形坡口对焊条件下,不同熔透状态熔池稠密视差图计算和表面形貌的三维重建.展开更多
Bragg's law with refractive correction of low-angle X-ray diffraction for periodic multilayers is deduced according to the optical refractive law and interference rules.Variant forms of this law,which accorded wit...Bragg's law with refractive correction of low-angle X-ray diffraction for periodic multilayers is deduced according to the optical refractive law and interference rules.Variant forms of this law,which accorded with experiments quite well,are given.展开更多
We present a random successive nucleation model to simulate the formation of the dense branching morphology(DBM)found in amorphous Al-Ge alloys.Our simulation shows that the DBM is obtained when the parameter K accoun...We present a random successive nucleation model to simulate the formation of the dense branching morphology(DBM)found in amorphous Al-Ge alloys.Our simulation shows that the DBM is obtained when the parameter K accounting for the structures of alloy films is small,and that a transition from DBM to fractals is found as K increases.展开更多
Double-crystal x-ray diffraction has been used to measure the rocking curve of Ta/Al multilayers.The diffraction profiles of the multilayers are different.Besides the normal profile,two kinds of distorted profiles hav...Double-crystal x-ray diffraction has been used to measure the rocking curve of Ta/Al multilayers.The diffraction profiles of the multilayers are different.Besides the normal profile,two kinds of distorted profiles have been found.The simulations show that the deformed profiles of the peaks are caused by the imperfect periodicity(e.g.systematic period deviation and coexistence of two slightly different periods)in the multilayers.展开更多
The a-Ge/p-Au bilayer thin films with different Au grain sizes were prepared.After annealing,different patterns of Ge appeared in the film morphology.It is found that the fractal dimensions of the patterns are highly ...The a-Ge/p-Au bilayer thin films with different Au grain sizes were prepared.After annealing,different patterns of Ge appeared in the film morphology.It is found that the fractal dimensions of the patterns are highly dependent on the grain size of Au,and the experimental results indicate that the fractal formation in such system is truly dominated by the local latent temperature field.展开更多
The broadening of X-ray diffraction peaks has been used successfully to measure the grain sizes of WSi_(2) in cosputtered W-Si films after annealing.The grain size of WSi_(2) increases with annealing temperature and r...The broadening of X-ray diffraction peaks has been used successfully to measure the grain sizes of WSi_(2) in cosputtered W-Si films after annealing.The grain size of WSi_(2) increases with annealing temperature and reaches 115nm after annealing at 1000°C.The grain sizes are quite similar to that obtained by transmission electron microscope in electron beam coevaporated film and low pressure chemical vapor deposited film.展开更多
文摘为实现完整熔池表面形貌三维传感,构建了双棱镜单摄像机立体视觉传感系统.针对熔池图像纹理缺乏造成的立体匹配困难的问题,引入了全局优化的变分立体匹配算法,通过建立包含灰度差异数据项和空间连续性约束项的能量函数的可行性泛函,经过迭代求解获得具有丰富细节的熔池表面稠密视差图.对自制非标准凹面形状进行立体匹配和三维重建,结果表明,宽度误差小于3.16%,深度误差小于4.82%.基于该算法实现了熔化极气体保护焊(gas metal arc welding,GMAW)的堆焊及V形坡口对焊条件下,不同熔透状态熔池稠密视差图计算和表面形貌的三维重建.
基金Supported by the National Natural Science Foundation of China.
文摘Bragg's law with refractive correction of low-angle X-ray diffraction for periodic multilayers is deduced according to the optical refractive law and interference rules.Variant forms of this law,which accorded with experiments quite well,are given.
文摘We present a random successive nucleation model to simulate the formation of the dense branching morphology(DBM)found in amorphous Al-Ge alloys.Our simulation shows that the DBM is obtained when the parameter K accounting for the structures of alloy films is small,and that a transition from DBM to fractals is found as K increases.
基金Supported by the National Natural Science Foundation of China。
文摘Double-crystal x-ray diffraction has been used to measure the rocking curve of Ta/Al multilayers.The diffraction profiles of the multilayers are different.Besides the normal profile,two kinds of distorted profiles have been found.The simulations show that the deformed profiles of the peaks are caused by the imperfect periodicity(e.g.systematic period deviation and coexistence of two slightly different periods)in the multilayers.
文摘The a-Ge/p-Au bilayer thin films with different Au grain sizes were prepared.After annealing,different patterns of Ge appeared in the film morphology.It is found that the fractal dimensions of the patterns are highly dependent on the grain size of Au,and the experimental results indicate that the fractal formation in such system is truly dominated by the local latent temperature field.
文摘The broadening of X-ray diffraction peaks has been used successfully to measure the grain sizes of WSi_(2) in cosputtered W-Si films after annealing.The grain size of WSi_(2) increases with annealing temperature and reaches 115nm after annealing at 1000°C.The grain sizes are quite similar to that obtained by transmission electron microscope in electron beam coevaporated film and low pressure chemical vapor deposited film.
