The Lagrange-I equations and measure differential equations for multibody systems with unilateral and bilateral constraints are constructed. For bilateral constraints, frictional forces and their impulses contain the ...The Lagrange-I equations and measure differential equations for multibody systems with unilateral and bilateral constraints are constructed. For bilateral constraints, frictional forces and their impulses contain the products of the filled-in relay function induced by Coulomb friction and the absolute values of normal constraint reactions. With the time-stepping impulse-velocity scheme, the measure differential equations are discretized. The equations of horizontal linear complementarity problems （HLCPs）, which are used to compute the impulses, are constructed by decomposing the absolute function and the filled-in relay function. These HLCP equations degenerate into equations of LCPs for frictional unilateral constraints, or HLCPs for frictional bilateral constraints. Finally, a numerical simulation for multibody systems with both unilateral and bilateral constraints is presented.展开更多
Statement of the Problem: Upper limb hemiparesis is a common impairment underlying disability after Stroke. Transfer of treatment to daily functioning remains a question for traditional approaches used in treatment of...Statement of the Problem: Upper limb hemiparesis is a common impairment underlying disability after Stroke. Transfer of treatment to daily functioning remains a question for traditional approaches used in treatment of upper extremity hemiparesis. Approaches based on Motor Learning principles may facilitate the transfer of treatment to activities of daily living. Methodology: Forty one subjects with chronic stroke, attending department of occupational therapy, National Institute for the Orthopaedically Handicapped, Kolkata, West Bengal, India participated in a single blinded randomized pre-test and post-test control group training study. Subjects were randomized over three intervention groups receiving modified Constraint Induced Movement Therapy (n = 13), Bilateral Arm training (n = 14), and an equally intensive conventional treatment program (n = 14). Subjects in the bilateral arm training group participated in bilateral symmetrical activities, where as subjects in constraint induced movement therapy group performed functional activities with the affected arm only and conventional group received conventional Occupational Therapy. Each group received intensive training for 1 hour/day, 5 days/week, for 8 weeks. Pre-treatment and post-treatment measures included the Fugl-Meyer measurement of physical performance (FMA- upper extremity section), action research arm test, motor activity log. Assessments were administered by a rater blinded to group assignment. Result: Both m-CIMT (p = 0.01) and bilateral arm training (p = 0.01) group showed statistically significant improvement in upper extremity functioning on Action Research Arm Test score in comparison to the conventional therapy group (p = 0.33). The bilateral arm training group had significantly greater improvement in upper arm function (Proximal Fugl-Meyer Assessment score, p = 0.001);while the constraint induced movement therapy group had greater improvement of hand functions (Distal Fugl-Meyer Assessment score, p = 0.001. There is an improvement seen in Quality of movement in the Conventional Therapy group. (p = 0.001). Conclusion: Both the treatment techniques can be used for upper extremity management in patients with chronic stroke. Bilateral arm training may be used to improve upper arm function and m-CIMT may be used to improve hand functions, while the group that received modified constraint induced movement therapy had greater improvement.展开更多
In the present study,we propose to integrate the bilateral filter into the Shepard-interpolation-based method for the optimization of composite structures.The bilateral filter is used to avoid defects in the structure...In the present study,we propose to integrate the bilateral filter into the Shepard-interpolation-based method for the optimization of composite structures.The bilateral filter is used to avoid defects in the structure that may arise due to the gap/overlap of adjacent fiber tows or excessive curvature of fiber tows.According to the bilateral filter,sensitivities at design points in the filter area are smoothed by both domain filtering and range filtering.Then,the filtered sensitivities are used to update the design variables.Through several numerical examples,the effectiveness of the method was verified.展开更多
压缩感知(CS)重构中的近似消息传递(AMP)算法通过迭代执行小波阈值操作和残差更新来快速准确地实现稀疏信号重构,但它所采用的小波系数稀疏约束并不适用于非稀疏的自然图像,尤其CS观测过程存在噪声干扰时.为此,文中提出了一种基于复合...压缩感知(CS)重构中的近似消息传递(AMP)算法通过迭代执行小波阈值操作和残差更新来快速准确地实现稀疏信号重构,但它所采用的小波系数稀疏约束并不适用于非稀疏的自然图像,尤其CS观测过程存在噪声干扰时.为此,文中提出了一种基于复合稀疏约束和AMP框架的CS图像重构算法,使用相似图像块低秩约束和双边滤波约束作为自然图像的联合先验信息,以改善图像规则纹理和边缘的恢复效果,从而提升算法的重构性能.无噪CS观测的重构实验表明,文中算法的峰值信噪比(PSNR)比仅用低秩约束的AMP算法提高了0.45 d B,比原始AMP算法高6.19 d B;而在含噪CS观测的重构实验中,对应的PSNR增益则分别是0.25和4.60 d B;无论是无噪观测还是含噪观测,文中算法都获得了更佳的主观视觉效果.展开更多
基金supported by the National Natural Science Foundation of China (10672007)
文摘The Lagrange-I equations and measure differential equations for multibody systems with unilateral and bilateral constraints are constructed. For bilateral constraints, frictional forces and their impulses contain the products of the filled-in relay function induced by Coulomb friction and the absolute values of normal constraint reactions. With the time-stepping impulse-velocity scheme, the measure differential equations are discretized. The equations of horizontal linear complementarity problems （HLCPs）, which are used to compute the impulses, are constructed by decomposing the absolute function and the filled-in relay function. These HLCP equations degenerate into equations of LCPs for frictional unilateral constraints, or HLCPs for frictional bilateral constraints. Finally, a numerical simulation for multibody systems with both unilateral and bilateral constraints is presented.
文摘Statement of the Problem: Upper limb hemiparesis is a common impairment underlying disability after Stroke. Transfer of treatment to daily functioning remains a question for traditional approaches used in treatment of upper extremity hemiparesis. Approaches based on Motor Learning principles may facilitate the transfer of treatment to activities of daily living. Methodology: Forty one subjects with chronic stroke, attending department of occupational therapy, National Institute for the Orthopaedically Handicapped, Kolkata, West Bengal, India participated in a single blinded randomized pre-test and post-test control group training study. Subjects were randomized over three intervention groups receiving modified Constraint Induced Movement Therapy (n = 13), Bilateral Arm training (n = 14), and an equally intensive conventional treatment program (n = 14). Subjects in the bilateral arm training group participated in bilateral symmetrical activities, where as subjects in constraint induced movement therapy group performed functional activities with the affected arm only and conventional group received conventional Occupational Therapy. Each group received intensive training for 1 hour/day, 5 days/week, for 8 weeks. Pre-treatment and post-treatment measures included the Fugl-Meyer measurement of physical performance (FMA- upper extremity section), action research arm test, motor activity log. Assessments were administered by a rater blinded to group assignment. Result: Both m-CIMT (p = 0.01) and bilateral arm training (p = 0.01) group showed statistically significant improvement in upper extremity functioning on Action Research Arm Test score in comparison to the conventional therapy group (p = 0.33). The bilateral arm training group had significantly greater improvement in upper arm function (Proximal Fugl-Meyer Assessment score, p = 0.001);while the constraint induced movement therapy group had greater improvement of hand functions (Distal Fugl-Meyer Assessment score, p = 0.001. There is an improvement seen in Quality of movement in the Conventional Therapy group. (p = 0.001). Conclusion: Both the treatment techniques can be used for upper extremity management in patients with chronic stroke. Bilateral arm training may be used to improve upper arm function and m-CIMT may be used to improve hand functions, while the group that received modified constraint induced movement therapy had greater improvement.
基金This research work was supported by the National Natural Science Foundation of China(Grant No.51975227)the Natural Science Foundation for Distinguished Young Scholars of Hubei Province,China(Grant No.2017CFA044).
文摘In the present study,we propose to integrate the bilateral filter into the Shepard-interpolation-based method for the optimization of composite structures.The bilateral filter is used to avoid defects in the structure that may arise due to the gap/overlap of adjacent fiber tows or excessive curvature of fiber tows.According to the bilateral filter,sensitivities at design points in the filter area are smoothed by both domain filtering and range filtering.Then,the filtered sensitivities are used to update the design variables.Through several numerical examples,the effectiveness of the method was verified.
文摘压缩感知(CS)重构中的近似消息传递(AMP)算法通过迭代执行小波阈值操作和残差更新来快速准确地实现稀疏信号重构,但它所采用的小波系数稀疏约束并不适用于非稀疏的自然图像,尤其CS观测过程存在噪声干扰时.为此,文中提出了一种基于复合稀疏约束和AMP框架的CS图像重构算法,使用相似图像块低秩约束和双边滤波约束作为自然图像的联合先验信息,以改善图像规则纹理和边缘的恢复效果,从而提升算法的重构性能.无噪CS观测的重构实验表明,文中算法的峰值信噪比(PSNR)比仅用低秩约束的AMP算法提高了0.45 d B,比原始AMP算法高6.19 d B;而在含噪CS观测的重构实验中,对应的PSNR增益则分别是0.25和4.60 d B;无论是无噪观测还是含噪观测,文中算法都获得了更佳的主观视觉效果.
