In this paper,we consider the algebraic structure of derivative Hardy Spaces.By using the method of[6,12,15],we get the Duhamel product forming Banach algebra in derivative Hardy Spaces,and invertibility criterion,and...In this paper,we consider the algebraic structure of derivative Hardy Spaces.By using the method of[6,12,15],we get the Duhamel product forming Banach algebra in derivative Hardy Spaces,and invertibility criterion,and describe the extended eigenvalue of the integral operator V.We generalize the results in[1,2,6,11,16].展开更多
Here we complete our work on the asymptotics of Hankel determinants studying the case wherein the entries are “ultrarapidly”-varying functions in the sense that their logarithms are rapidly varying. Moreover, the la...Here we complete our work on the asymptotics of Hankel determinants studying the case wherein the entries are “ultrarapidly”-varying functions in the sense that their logarithms are rapidly varying. Moreover, the last results in the paper highlight analogies between algebraic identities for Hankelians with special entries and asymptotic relations valid for large classes of entries.展开更多
目的探讨脑小血管病(CSVD)患者外周血G蛋白耦联雌激素受体30(GPER30)、神经元PAS结构域蛋白4(NPAS4)、FK506结合蛋白5(FKBP5)表达与认知功能障碍(CD)的相关性。方法前瞻性选取2022年1月至2023年12月郑州大学第二附属医院收治的227例CSV...目的探讨脑小血管病(CSVD)患者外周血G蛋白耦联雌激素受体30(GPER30)、神经元PAS结构域蛋白4(NPAS4)、FK506结合蛋白5(FKBP5)表达与认知功能障碍(CD)的相关性。方法前瞻性选取2022年1月至2023年12月郑州大学第二附属医院收治的227例CSVD患者,根据有无CD分为障碍组(n=66)与无障碍组(n=161)。比较两组患者的一般资料及外周血GPER30、NPAS4、FKBP5 m RNA表达水平,Logistic回归分析CSVD患者CD的影响因素,比较不同程度CD患者外周血GPER30、NPAS4、FKBP5 m RNA表达水平,采用Pearson法分析外周血GPER30、NPAS4、FKBP5 m RNA表达与蒙特利尔认知评估量表(Mo CA)评分的相关性。结果障碍组患者的年龄、病程分别为(72.49±5.68)岁、(2.69±0.78)年,明显高(长)于无障碍组的(67.51±7.04)岁、(2.31±0.62)年,差异均有统计学意义(P<0.05);障碍组患者的外周血GPER30 m RNA表达水平为1.02±0.17,明显低于无障碍组的1.66±0.31,NPAS4m RNA、FKBP5 m RNA表达水平分别为2.79±0.60、3.88±1.12,明显高于无障碍组的1.55±0.51、2.10±0.59,差异均有统计学意义(P<0.05);Logistic回归分析结果显示,年龄、病程、GPER30 m RNA、NPAS4 m RNA及FKBP5 m RNA均为CSVD患者CD的独立影响因素(P<0.05)。轻度组患者的外周血GPER30 m RNA表达水平为1.27±0.25,明显高于中重度组的0.70±0.12,NPAS4 m RNA、FKBP5 m RNA表达水平分别为2.31±0.58、3.19±1.07,明显低于中重度组的3.40±0.72、4.76±1.39,差异均有统计学意义(P<0.05);Pearson法分析结果显示,外周血GPER30 m RNA表达与CSVD患者Mo CA评分呈正相关(r=0.704,P<0.05),NPAS4 m RNA、FKBP5 m RNA与Mo CA评分呈负相关(r=-0.572、-0.542,P<0.05)。结论外周血GPER30、NPAS4、FKBP5是CSVD患者CD的独立相关因素,各指标表达水平与CD病情严重程度均具有一定相关性,可为临床判断CD、评估CD病情严重程度提供参考,以指导后续临床工作。展开更多
Based on the dual source cumulative rotation technique in the time-domain proposed by Zeng and MacBeth（1993）,a new algebraic processing technique for extracting shear-wave splitting parameters from multi-component V...Based on the dual source cumulative rotation technique in the time-domain proposed by Zeng and MacBeth（1993）,a new algebraic processing technique for extracting shear-wave splitting parameters from multi-component VSP data in frequency-dependent medium has been developed.By using this dual source cumulative rotation technique in the frequency-domain（DCTF）,anisotropic parameters,including polarization direction of the shear-waves and timedelay between the fast and slow shear-waves,can be estimated for each frequency component in the frequency domain.It avoids the possible error which comes from using a narrow-band filter in the current commonly used method.By using synthetic seismograms,the feasibility and validity of the technique was tested and a comparison with the currently used method was also given.The results demonstrate that the shear-wave splitting parameters frequency dependence can be extracted directly from four-component seismic data using the DCTF.In the presence of larger scale fractures,substantial frequency dependence would be found in the seismic frequency range,which implies that dispersion would occur at seismic frequencies.Our study shows that shear-wave anisotropy decreases as frequency increases.展开更多
Singular configurations must be avoided in path planning and control of a parallel manipulator. However, most studies rarely focus on an overall singularity loci distribution of lower-mobility parallel mechanisms. Geo...Singular configurations must be avoided in path planning and control of a parallel manipulator. However, most studies rarely focus on an overall singularity loci distribution of lower-mobility parallel mechanisms. Geometric algebra is employed in analysis of singularity of a 3-RPS parallel manipulator. Twist and wrench in screw theory are represented in geometric algebra. Linear dependency of twists and wrenches are described by outer product in geometric algebra. Reciprocity between twists and constraint wrenches are reflected by duality. To compute the positions of the three spherical joints of the 3-RPS parallel manipulator, Tilt-and-Torsion angles are used to describe the orientation of the moving platform. The outer product of twists and constraint wrenches is used as an index for closeness to singularity（ICS） of the 3-RPS parallel manipulator. An overall and thorough perspective of the singularity loci distribution of the 3-RPS parallel manipulator is disclosed, which is helpful to design, trajectory planning and control of this kind of parallel manipulator.展开更多
As the dynamic equations of space robots are highly nonlinear,strongly coupled and nonholonomic constrained,the efficiency of current dynamic modeling algorithms is difficult to meet the requirements of real-time simu...As the dynamic equations of space robots are highly nonlinear,strongly coupled and nonholonomic constrained,the efficiency of current dynamic modeling algorithms is difficult to meet the requirements of real-time simulation.This paper combines an efficient spatial operator algebra（SOA） algorithm for base fixed robots with the conservation of linear and angular momentum theory to establish dynamic equations for the free-floating space robot,and analyzes the influence to the base body＇s position and posture when the manipulator is capturing a target.The recursive Newton-Euler kinematic equations on screw form for the space robot are derived,and the techniques of the sequential filtering and smoothing methods in optimal estimation theory are used to derive an innovation factorization and inverse of the generalized mass matrix which immediately achieve high computational efficiency.The high efficient SOA algorithm is spatially recursive and has a simple math expression and a clear physical understanding,and its computational complexity grows only linearly with the number of degrees of freedom.Finally,a space robot with three degrees of freedom manipulator is simulated in Matematica 6.0.Compared with ADAMS,the simulation reveals that the SOA algorithm is much more efficient to solve the forward and inverse dynamic problems.As a result,the requirements of real-time simulation for dynamics of free-floating space robot are solved and a new analytic modeling system is established for free-floating space robot.展开更多
基金Supported by National Natural Science Foundation of China(11801094).
文摘In this paper,we consider the algebraic structure of derivative Hardy Spaces.By using the method of[6,12,15],we get the Duhamel product forming Banach algebra in derivative Hardy Spaces,and invertibility criterion,and describe the extended eigenvalue of the integral operator V.We generalize the results in[1,2,6,11,16].
文摘Here we complete our work on the asymptotics of Hankel determinants studying the case wherein the entries are “ultrarapidly”-varying functions in the sense that their logarithms are rapidly varying. Moreover, the last results in the paper highlight analogies between algebraic identities for Hankelians with special entries and asymptotic relations valid for large classes of entries.
文摘目的探讨脑小血管病(CSVD)患者外周血G蛋白耦联雌激素受体30(GPER30)、神经元PAS结构域蛋白4(NPAS4)、FK506结合蛋白5(FKBP5)表达与认知功能障碍(CD)的相关性。方法前瞻性选取2022年1月至2023年12月郑州大学第二附属医院收治的227例CSVD患者,根据有无CD分为障碍组(n=66)与无障碍组(n=161)。比较两组患者的一般资料及外周血GPER30、NPAS4、FKBP5 m RNA表达水平,Logistic回归分析CSVD患者CD的影响因素,比较不同程度CD患者外周血GPER30、NPAS4、FKBP5 m RNA表达水平,采用Pearson法分析外周血GPER30、NPAS4、FKBP5 m RNA表达与蒙特利尔认知评估量表(Mo CA)评分的相关性。结果障碍组患者的年龄、病程分别为(72.49±5.68)岁、(2.69±0.78)年,明显高(长)于无障碍组的(67.51±7.04)岁、(2.31±0.62)年,差异均有统计学意义(P<0.05);障碍组患者的外周血GPER30 m RNA表达水平为1.02±0.17,明显低于无障碍组的1.66±0.31,NPAS4m RNA、FKBP5 m RNA表达水平分别为2.79±0.60、3.88±1.12,明显高于无障碍组的1.55±0.51、2.10±0.59,差异均有统计学意义(P<0.05);Logistic回归分析结果显示,年龄、病程、GPER30 m RNA、NPAS4 m RNA及FKBP5 m RNA均为CSVD患者CD的独立影响因素(P<0.05)。轻度组患者的外周血GPER30 m RNA表达水平为1.27±0.25,明显高于中重度组的0.70±0.12,NPAS4 m RNA、FKBP5 m RNA表达水平分别为2.31±0.58、3.19±1.07,明显低于中重度组的3.40±0.72、4.76±1.39,差异均有统计学意义(P<0.05);Pearson法分析结果显示,外周血GPER30 m RNA表达与CSVD患者Mo CA评分呈正相关(r=0.704,P<0.05),NPAS4 m RNA、FKBP5 m RNA与Mo CA评分呈负相关(r=-0.572、-0.542,P<0.05)。结论外周血GPER30、NPAS4、FKBP5是CSVD患者CD的独立相关因素,各指标表达水平与CD病情严重程度均具有一定相关性,可为临床判断CD、评估CD病情严重程度提供参考,以指导后续临床工作。
基金supported by the National Natural Science Foundation of China (No. 41004055)
文摘Based on the dual source cumulative rotation technique in the time-domain proposed by Zeng and MacBeth（1993）,a new algebraic processing technique for extracting shear-wave splitting parameters from multi-component VSP data in frequency-dependent medium has been developed.By using this dual source cumulative rotation technique in the frequency-domain（DCTF）,anisotropic parameters,including polarization direction of the shear-waves and timedelay between the fast and slow shear-waves,can be estimated for each frequency component in the frequency domain.It avoids the possible error which comes from using a narrow-band filter in the current commonly used method.By using synthetic seismograms,the feasibility and validity of the technique was tested and a comparison with the currently used method was also given.The results demonstrate that the shear-wave splitting parameters frequency dependence can be extracted directly from four-component seismic data using the DCTF.In the presence of larger scale fractures,substantial frequency dependence would be found in the seismic frequency range,which implies that dispersion would occur at seismic frequencies.Our study shows that shear-wave anisotropy decreases as frequency increases.
基金Supported by National Natural Science Foundation of China(Grant No.51135008)Zhejiang Provincial Natural Science Foundation of China(Grant No.LZ14E050005)
文摘Singular configurations must be avoided in path planning and control of a parallel manipulator. However, most studies rarely focus on an overall singularity loci distribution of lower-mobility parallel mechanisms. Geometric algebra is employed in analysis of singularity of a 3-RPS parallel manipulator. Twist and wrench in screw theory are represented in geometric algebra. Linear dependency of twists and wrenches are described by outer product in geometric algebra. Reciprocity between twists and constraint wrenches are reflected by duality. To compute the positions of the three spherical joints of the 3-RPS parallel manipulator, Tilt-and-Torsion angles are used to describe the orientation of the moving platform. The outer product of twists and constraint wrenches is used as an index for closeness to singularity（ICS） of the 3-RPS parallel manipulator. An overall and thorough perspective of the singularity loci distribution of the 3-RPS parallel manipulator is disclosed, which is helpful to design, trajectory planning and control of this kind of parallel manipulator.
基金supported by National Natural Science Foundation of China (Grant No. 50375071)Commission of Science, Technology and Industry for National Defense Pre-research Foundation of China (Grant No. C4220062501)
文摘As the dynamic equations of space robots are highly nonlinear,strongly coupled and nonholonomic constrained,the efficiency of current dynamic modeling algorithms is difficult to meet the requirements of real-time simulation.This paper combines an efficient spatial operator algebra（SOA） algorithm for base fixed robots with the conservation of linear and angular momentum theory to establish dynamic equations for the free-floating space robot,and analyzes the influence to the base body＇s position and posture when the manipulator is capturing a target.The recursive Newton-Euler kinematic equations on screw form for the space robot are derived,and the techniques of the sequential filtering and smoothing methods in optimal estimation theory are used to derive an innovation factorization and inverse of the generalized mass matrix which immediately achieve high computational efficiency.The high efficient SOA algorithm is spatially recursive and has a simple math expression and a clear physical understanding,and its computational complexity grows only linearly with the number of degrees of freedom.Finally,a space robot with three degrees of freedom manipulator is simulated in Matematica 6.0.Compared with ADAMS,the simulation reveals that the SOA algorithm is much more efficient to solve the forward and inverse dynamic problems.As a result,the requirements of real-time simulation for dynamics of free-floating space robot are solved and a new analytic modeling system is established for free-floating space robot.
