在固定硬涂层形状的前提下寻找最佳的涂敷位置是工程化实施硬涂层阻尼减振的迫切需求。以硬涂层薄板为例,研究实现上述硬涂层阻尼优化的方法。针对局部涂敷硬涂层的薄板结构完成了有限元建模,并利用修正模态应变能法确定了涂层复合结构...在固定硬涂层形状的前提下寻找最佳的涂敷位置是工程化实施硬涂层阻尼减振的迫切需求。以硬涂层薄板为例,研究实现上述硬涂层阻尼优化的方法。针对局部涂敷硬涂层的薄板结构完成了有限元建模,并利用修正模态应变能法确定了涂层复合结构的模态损耗因子。以获得单阶次或者多阶次最大模态损耗因子为目标,以涂层位置为设计变量描述了该硬涂层薄板阻尼优化模型。提出利用多种群遗传算法求解该优化问题的方法。以单面局部涂敷Ni Cr Al Co Y+YSZ硬涂层材料的悬臂板为例进行了实例研究,基于所创建的优化模型和优化方法,在薄板上实施了硬涂层涂敷位置的优化,并用实验验证了硬涂层板阻尼优化结果的合理性。展开更多
A foil–microchannel plate(MCP)detector,which uses electrostatic lenses and possesses both good position and timing resolutions,has been designed and simulated for beam diagnostics and mass measurements at the next-ge...A foil–microchannel plate(MCP)detector,which uses electrostatic lenses and possesses both good position and timing resolutions,has been designed and simulated for beam diagnostics and mass measurements at the next-generation heavy-ion-beam facility HIAF in China.Characterized by low energy loss and good performances of timing and position measurements,it would be located at focal planes in fragment separator HFRS for position monitoring,beam turning,Bq measurement,and trajectory reconstruction.Moreover,it will benefit the building-up of a magnetic-rigidity–energy-loss–time-offlight(BqDETOF)method at HFRS for high-precision in-flight particle identification of radioactive isotope beams on an event-by-event basis.Most importantly,the detector can be utilized for in-ring TOF and position measurements,beam-line TOF measurements at two achromatic foci,and position measurements at a dispersive focus of HFRS,thus making it possible to use two complementary mass measurement methods[isochronous mass spectrometry at the storage ring SRing and magnetic-rigidity–time-of-flight(BqTOF)at the beam-line HFRS]in one single experimental run.展开更多
An efficient vehicle detection approach is proposed for traffic surveillance images, which is based on information fusion of vehicle symmetrical contour and license plate position. The vertical symmetry axis of the ve...An efficient vehicle detection approach is proposed for traffic surveillance images, which is based on information fusion of vehicle symmetrical contour and license plate position. The vertical symmetry axis of the vehicle contour in an image is. first detected, and then the vertical and the horizontal symmetry axes of the license plate are detected using the symmetry axis of the vehicle contour as a reference. The vehicle location in an image is determined using license plate symmetry axes and the vertical and the horizontal projection maps of the vehicle edge image. A dataset consisting of 450 images （15 classes of vehicles） is used to test the proposed method. The experimental results indicate that compared with the vehicle contour-based, the license plate location-based, the vehicle texture-based and the Gabor feature-based methods, the proposed method is the best with a detection accuracy of 90.7% and an elapsed time of 125 ms.展开更多
文摘在固定硬涂层形状的前提下寻找最佳的涂敷位置是工程化实施硬涂层阻尼减振的迫切需求。以硬涂层薄板为例,研究实现上述硬涂层阻尼优化的方法。针对局部涂敷硬涂层的薄板结构完成了有限元建模,并利用修正模态应变能法确定了涂层复合结构的模态损耗因子。以获得单阶次或者多阶次最大模态损耗因子为目标,以涂层位置为设计变量描述了该硬涂层薄板阻尼优化模型。提出利用多种群遗传算法求解该优化问题的方法。以单面局部涂敷Ni Cr Al Co Y+YSZ硬涂层材料的悬臂板为例进行了实例研究,基于所创建的优化模型和优化方法,在薄板上实施了硬涂层涂敷位置的优化,并用实验验证了硬涂层板阻尼优化结果的合理性。
基金supported by the National Natural Science Foundation of China(Nos.11605248,11605249,11605267,and 11805032.)
文摘A foil–microchannel plate(MCP)detector,which uses electrostatic lenses and possesses both good position and timing resolutions,has been designed and simulated for beam diagnostics and mass measurements at the next-generation heavy-ion-beam facility HIAF in China.Characterized by low energy loss and good performances of timing and position measurements,it would be located at focal planes in fragment separator HFRS for position monitoring,beam turning,Bq measurement,and trajectory reconstruction.Moreover,it will benefit the building-up of a magnetic-rigidity–energy-loss–time-offlight(BqDETOF)method at HFRS for high-precision in-flight particle identification of radioactive isotope beams on an event-by-event basis.Most importantly,the detector can be utilized for in-ring TOF and position measurements,beam-line TOF measurements at two achromatic foci,and position measurements at a dispersive focus of HFRS,thus making it possible to use two complementary mass measurement methods[isochronous mass spectrometry at the storage ring SRing and magnetic-rigidity–time-of-flight(BqTOF)at the beam-line HFRS]in one single experimental run.
基金The National Natural Science Foundation of China(No. 40804015,61101163)
文摘An efficient vehicle detection approach is proposed for traffic surveillance images, which is based on information fusion of vehicle symmetrical contour and license plate position. The vertical symmetry axis of the vehicle contour in an image is. first detected, and then the vertical and the horizontal symmetry axes of the license plate are detected using the symmetry axis of the vehicle contour as a reference. The vehicle location in an image is determined using license plate symmetry axes and the vertical and the horizontal projection maps of the vehicle edge image. A dataset consisting of 450 images （15 classes of vehicles） is used to test the proposed method. The experimental results indicate that compared with the vehicle contour-based, the license plate location-based, the vehicle texture-based and the Gabor feature-based methods, the proposed method is the best with a detection accuracy of 90.7% and an elapsed time of 125 ms.
