Objective To realize accurate localization of moving vehicles from single monocular intens ity image. Methods The new modified Hausdorff distance(M2HD) was adopted, which used dominant points instead of edge maps a...Objective To realize accurate localization of moving vehicles from single monocular intens ity image. Methods The new modified Hausdorff distance(M2HD) was adopted, which used dominant points instead of edge maps as features for mea suring similarity between image and model projection. Modified simulated anneali ng (MSA) algorithm was used to find optimum localization parameters. Res ults M2HD reduces the computational complexity, and improves the matc hing precision. Furthermore, MSA can fast find global optimum instead of getting into partial one because of its high parallel and robust performance. C onclusion Experiments confirm that the combination of MSA and M 2H D can effectively localize the vehicles that are changed both in translation and rotation展开更多
Self-locked energy-absorbing systems have been proposed in previous studies to overcome the limitations associated with the round-tube systems because they can prevent the lateral splash of tubes from impact loadings ...Self-locked energy-absorbing systems have been proposed in previous studies to overcome the limitations associated with the round-tube systems because they can prevent the lateral splash of tubes from impact loadings without any constraints.In case of self-locked systems,the ellipse-shaped self-locked tube is considered to be an optimal design when compared with the ordinary circle-shaped self-locked tubes and other shaped self-locked tubes.In this study,we aim to theoretically analyze the ellipseshaped self-locked tubes.Further,a plastic hinge model is developed to predict the force-displacement relation of the tube,which is compared with the deformation process observed in the experiment and finite element method(FEM)simulation.Using this model,the effects of tuning the geometric parameters of the tube on the energy absorption performance,including the deformation efficiency,energy absorption capacity,and effective stroke ratio,are simulated and analyzed.Finally,a guideline is provided with respect to the design of the ellipse-shaped self-locked tube in engineering applications.展开更多
Recently Hari Shroff and his collaborators[Nano Letters 5(2005)]developed a nanoscopic force sensor,but the force which they measured in their single molecular experiment was much lower than the theoretical critical v...Recently Hari Shroff and his collaborators[Nano Letters 5(2005)]developed a nanoscopic force sensor,but the force which they measured in their single molecular experiment was much lower than the theoretical critical value.In order to fix this problem,we investigate the micromechanics of dsDNA based on the worm-like chain model and flexible hinge model by using Monte Carlo algorithm.The simulation results not only address Hari Shroff’s experiment difficulty reasonably,but also provide strong support for flexible hinge mechanism put forward recently by Yan and Marko[Phys.Rev.Lett.93(2004)].展开更多
文摘Objective To realize accurate localization of moving vehicles from single monocular intens ity image. Methods The new modified Hausdorff distance(M2HD) was adopted, which used dominant points instead of edge maps as features for mea suring similarity between image and model projection. Modified simulated anneali ng (MSA) algorithm was used to find optimum localization parameters. Res ults M2HD reduces the computational complexity, and improves the matc hing precision. Furthermore, MSA can fast find global optimum instead of getting into partial one because of its high parallel and robust performance. C onclusion Experiments confirm that the combination of MSA and M 2H D can effectively localize the vehicles that are changed both in translation and rotation
基金the National Natural Science Foundation of China(Grant Nos.11622214,11472027,and 11202012)the Academic Excellence Foundation of Beihang University for PhD Students。
文摘Self-locked energy-absorbing systems have been proposed in previous studies to overcome the limitations associated with the round-tube systems because they can prevent the lateral splash of tubes from impact loadings without any constraints.In case of self-locked systems,the ellipse-shaped self-locked tube is considered to be an optimal design when compared with the ordinary circle-shaped self-locked tubes and other shaped self-locked tubes.In this study,we aim to theoretically analyze the ellipseshaped self-locked tubes.Further,a plastic hinge model is developed to predict the force-displacement relation of the tube,which is compared with the deformation process observed in the experiment and finite element method(FEM)simulation.Using this model,the effects of tuning the geometric parameters of the tube on the energy absorption performance,including the deformation efficiency,energy absorption capacity,and effective stroke ratio,are simulated and analyzed.Finally,a guideline is provided with respect to the design of the ellipse-shaped self-locked tube in engineering applications.
基金This research was supported by the Young Investigator Award received by Yan in 2006 and the Foundation for the Visiting PhD Candidate of the Chinese Academy of Science received by Liu in 2006Liu is also supported by the Innovation Foundation for Graduate Students of Guizhou University(2007022).
文摘Recently Hari Shroff and his collaborators[Nano Letters 5(2005)]developed a nanoscopic force sensor,but the force which they measured in their single molecular experiment was much lower than the theoretical critical value.In order to fix this problem,we investigate the micromechanics of dsDNA based on the worm-like chain model and flexible hinge model by using Monte Carlo algorithm.The simulation results not only address Hari Shroff’s experiment difficulty reasonably,but also provide strong support for flexible hinge mechanism put forward recently by Yan and Marko[Phys.Rev.Lett.93(2004)].
