It is shown that if a 'max-subadditive funtional' p(x) defined on some symmetric neighborhood U0 of zero vector θ in a 'b.f.-toplological group' X is 'upper semi-cotinuous' at a point x0 ∈ U0...It is shown that if a 'max-subadditive funtional' p(x) defined on some symmetric neighborhood U0 of zero vector θ in a 'b.f.-toplological group' X is 'upper semi-cotinuous' at a point x0 ∈ U0, or 'lower semi-continuous' in some neighborhood V(x0) U0 and X is of second category; then p(x) can attain its supremum in U0. And there is a similar conclusion for the γ-max-subadditive functional when its supremum is 0 and if U0 is 'pseudo-bounded' set in X.展开更多
This paper introduces a new exact and smooth penalty function to tackle constrained min-max problems. By using this new penalty function and adding just one extra variable, a constrained rain-max problem is transforme...This paper introduces a new exact and smooth penalty function to tackle constrained min-max problems. By using this new penalty function and adding just one extra variable, a constrained rain-max problem is transformed into an unconstrained optimization one. It is proved that, under certain reasonable assumptions and when the penalty parameter is sufficiently large, the minimizer of this unconstrained optimization problem is equivalent to the minimizer of the original constrained one. Numerical results demonstrate that this penalty function method is an effective and promising approach for solving constrained finite min-max problems.展开更多
Objective This study attempted to seek a new Doppler-derived index for estimating ventricularsystolic function. Methods With custom - made software the aortic and pulmonic flow profiles were digitized andconverted to ...Objective This study attempted to seek a new Doppler-derived index for estimating ventricularsystolic function. Methods With custom - made software the aortic and pulmonic flow profiles were digitized andconverted to their 4V2 curves, their maximum value of the first derivative, max (dk/dt) were obtained separately in23 and 25patients with congenital heart disease (mean age 4.5 years). Aortic max(dk/dt) and pulmonic max(dk/dt)measured by Doppler were compared with left ventricular max(dp/dt) and right ventricular max(dp/dt) measuredby cardiac catheterization. Results Aortic max(dk/dt) correlated well with LV max(dp/dt) (r=0.817, P<0.001).An excellent correlation of pulmonic max(dk/dt) with RV max(dp/dt) was established (r=0.926, P<0.0001). Therewas a significant correlation between RVSP and RV max(dp/dt) (r= 0.839, P<0.0001). Conclusion Doppler - derived aortic max(dk/dt) and pulmonic max(dk/dt) could be reliable index of left ventricular contractility and rightventricular contractility respectively. When max(dp/dt) is used for assessing RV systolic function, the impact ofRVSP on that should be taken into consideration.展开更多
为了给驾驶员提供实时准确的行人信息、减少交通事故的发生,提出一种检测增强型YOLOv3-tiny(detection of enhanced YOLOv3-tiny,DOEYT)行人检测算法.创建鲁棒的特征提取网络,首先使用非对称最大池化进行下采样,防止随着感受野增大行人...为了给驾驶员提供实时准确的行人信息、减少交通事故的发生,提出一种检测增强型YOLOv3-tiny(detection of enhanced YOLOv3-tiny,DOEYT)行人检测算法.创建鲁棒的特征提取网络,首先使用非对称最大池化进行下采样,防止随着感受野增大行人横向特征的丢失;其次使用Hardswish作为卷积层的激活函数优化网络性能;最后使用GC(globe context)自注意力机制获得全文特征信息.在分类回归网络部分,采用三尺度检测策略,提升小尺度行人目标的检测精度;使用k-means++算法重新生成数据集锚框,提高网络收敛速度.构建行人检测数据集并分为训练集和测试集,对DOEYT算法的性能进行试验验证.结果表明,非对称最大池化、Hardswish函数、GC自注意力机制分别使平均准确率AP提高14.4%、7.9%、10.8%;DOEYT算法在测试集上检测的平均准确率高达91.2%,检测速度为103帧/s,可见该算法可快速准确地检测行人,降低交通事故发生的风险.展开更多
文摘将α-Fe_(2)O_(3)@C与钛粉和铝粉一同进行高温煅烧,制备了Fe O@C/MAX(FCM)复合材料。通过XRD、SEM、TEM表征了FCM复合材料在不同Ti/C与Al/C物质的量比下的结构、组成及形貌变化,采用电化学动力学分析方法定量计算了FCM复合材料的赝电容占比,推测可能的电荷储存机理。结果表明,随着Ti/C与Al/C物质的量比的增大,FCM复合材料中MAX相(Ti_(2)Al C和Ti_(3)Al C_(2))的含量随之变化,而α-Fe_(2)O_(3)转变为不稳定的Fe O。当n(Ti)∶n(Al)∶n(C)=3∶1∶2时,制得的FCM-312样品在1 m V/s扫描速率下的比电容最大,为125.09 F/g,约为α-Fe_(2)O_(3)@C的4.76倍。FCM复合材料中部分MAX相在电化学过程中发生氧化还原反应,为离子间电子快速输运提供了条件,增加了FCM复合材料的赝电容占比。其中,FCM-312样品在10 m V/s扫描速率下的赝电容占比为22.12%。
文摘It is shown that if a 'max-subadditive funtional' p(x) defined on some symmetric neighborhood U0 of zero vector θ in a 'b.f.-toplological group' X is 'upper semi-cotinuous' at a point x0 ∈ U0, or 'lower semi-continuous' in some neighborhood V(x0) U0 and X is of second category; then p(x) can attain its supremum in U0. And there is a similar conclusion for the γ-max-subadditive functional when its supremum is 0 and if U0 is 'pseudo-bounded' set in X.
基金supported by the Grant of the Academy of Mathematics and System Science of Chinese Academy of Sciences-The Hong Kong Polytechnic University Joint Research Institute (AMSS-PolyU)the Research Grands Council Grant of The Hong Kong Polytechnic University (No. 5365/09E)
文摘This paper introduces a new exact and smooth penalty function to tackle constrained min-max problems. By using this new penalty function and adding just one extra variable, a constrained rain-max problem is transformed into an unconstrained optimization one. It is proved that, under certain reasonable assumptions and when the penalty parameter is sufficiently large, the minimizer of this unconstrained optimization problem is equivalent to the minimizer of the original constrained one. Numerical results demonstrate that this penalty function method is an effective and promising approach for solving constrained finite min-max problems.
文摘Objective This study attempted to seek a new Doppler-derived index for estimating ventricularsystolic function. Methods With custom - made software the aortic and pulmonic flow profiles were digitized andconverted to their 4V2 curves, their maximum value of the first derivative, max (dk/dt) were obtained separately in23 and 25patients with congenital heart disease (mean age 4.5 years). Aortic max(dk/dt) and pulmonic max(dk/dt)measured by Doppler were compared with left ventricular max(dp/dt) and right ventricular max(dp/dt) measuredby cardiac catheterization. Results Aortic max(dk/dt) correlated well with LV max(dp/dt) (r=0.817, P<0.001).An excellent correlation of pulmonic max(dk/dt) with RV max(dp/dt) was established (r=0.926, P<0.0001). Therewas a significant correlation between RVSP and RV max(dp/dt) (r= 0.839, P<0.0001). Conclusion Doppler - derived aortic max(dk/dt) and pulmonic max(dk/dt) could be reliable index of left ventricular contractility and rightventricular contractility respectively. When max(dp/dt) is used for assessing RV systolic function, the impact ofRVSP on that should be taken into consideration.
文摘为了给驾驶员提供实时准确的行人信息、减少交通事故的发生,提出一种检测增强型YOLOv3-tiny(detection of enhanced YOLOv3-tiny,DOEYT)行人检测算法.创建鲁棒的特征提取网络,首先使用非对称最大池化进行下采样,防止随着感受野增大行人横向特征的丢失;其次使用Hardswish作为卷积层的激活函数优化网络性能;最后使用GC(globe context)自注意力机制获得全文特征信息.在分类回归网络部分,采用三尺度检测策略,提升小尺度行人目标的检测精度;使用k-means++算法重新生成数据集锚框,提高网络收敛速度.构建行人检测数据集并分为训练集和测试集,对DOEYT算法的性能进行试验验证.结果表明,非对称最大池化、Hardswish函数、GC自注意力机制分别使平均准确率AP提高14.4%、7.9%、10.8%;DOEYT算法在测试集上检测的平均准确率高达91.2%,检测速度为103帧/s,可见该算法可快速准确地检测行人,降低交通事故发生的风险.
