A new smooth gap function for the box constrained variational inequality problem （VIP） is proposed based on an integral global optimality condition. The smooth gap function is simple and has some good differentiable...A new smooth gap function for the box constrained variational inequality problem （VIP） is proposed based on an integral global optimality condition. The smooth gap function is simple and has some good differentiable properties. The box constrained VIP can be reformulated as a differentiable optimization problem by the proposed smooth gap function. The conditions, under which any stationary point of the optimization problem is the solution to the box constrained VIP, are discussed. A simple frictional contact problem is analyzed to show the applications of the smooth gap function. Finally, the numerical experiments confirm the good theoretical properties of the method.展开更多
目的建立基于静息态功能磁共振(functional magnetic resonance imaging,fMRI)低频振幅(amplitude of low-frequency fluctuation,ALFF)数据预测早期精神分裂症(schizophrenia,SZ)患者视觉信息处理速度(visual information processing s...目的建立基于静息态功能磁共振(functional magnetic resonance imaging,fMRI)低频振幅(amplitude of low-frequency fluctuation,ALFF)数据预测早期精神分裂症(schizophrenia,SZ)患者视觉信息处理速度(visual information processing speed,VIPS)的模型。方法纳入31例早期SZ患者和33名正常对照者,用连线测验(trail making test,TMT)评估受试者VIPS,使用支持向量回归(support vector regression,SVR)以两组ALFF差异脑区作为模板定量预测患者组VIPS评分。结果两组的VIPS差异存在统计学意义(P<0.01)。与对照组相比,患者组ALFF值升高主要分布在边缘叶(P<0.01,AlphaSim校正),而ALFF值降低主要分布在额叶、顶叶和枕叶(P<0.01,AlphaSim校正)。SVR结果显示,SZ异常脑区ALFF值可有效预测VIPS(r=0.62,P=0.04)。SVR过程中权重高的脑区包括右侧楔前叶、右侧辅助运动区和右侧中央后回,其中,右侧楔前叶ALFF值与VIPS相关(r=0.50,P<0.01)。结论早期SZ患者部分异常脑区自发活动与VIPS相关且可有效预测VIPS,这提示脑区自发活动可能是SZ患者VIPS受损的预测指标和客观生物标志物。展开更多
基金Project supported by the National Natural Science Foundation of China(Nos.10902077,11172209, and 10572031)
文摘A new smooth gap function for the box constrained variational inequality problem （VIP） is proposed based on an integral global optimality condition. The smooth gap function is simple and has some good differentiable properties. The box constrained VIP can be reformulated as a differentiable optimization problem by the proposed smooth gap function. The conditions, under which any stationary point of the optimization problem is the solution to the box constrained VIP, are discussed. A simple frictional contact problem is analyzed to show the applications of the smooth gap function. Finally, the numerical experiments confirm the good theoretical properties of the method.
文摘目的建立基于静息态功能磁共振(functional magnetic resonance imaging,fMRI)低频振幅(amplitude of low-frequency fluctuation,ALFF)数据预测早期精神分裂症(schizophrenia,SZ)患者视觉信息处理速度(visual information processing speed,VIPS)的模型。方法纳入31例早期SZ患者和33名正常对照者,用连线测验(trail making test,TMT)评估受试者VIPS,使用支持向量回归(support vector regression,SVR)以两组ALFF差异脑区作为模板定量预测患者组VIPS评分。结果两组的VIPS差异存在统计学意义(P<0.01)。与对照组相比,患者组ALFF值升高主要分布在边缘叶(P<0.01,AlphaSim校正),而ALFF值降低主要分布在额叶、顶叶和枕叶(P<0.01,AlphaSim校正)。SVR结果显示,SZ异常脑区ALFF值可有效预测VIPS(r=0.62,P=0.04)。SVR过程中权重高的脑区包括右侧楔前叶、右侧辅助运动区和右侧中央后回,其中,右侧楔前叶ALFF值与VIPS相关(r=0.50,P<0.01)。结论早期SZ患者部分异常脑区自发活动与VIPS相关且可有效预测VIPS,这提示脑区自发活动可能是SZ患者VIPS受损的预测指标和客观生物标志物。
