Let E be a holomophic vector bundle over a compact Astheno-Kähler manifold(M,ω).The authors would prove that E is a numerically flat vector bundle if E is pseudoeffective and the first Chern class c_(1)^(BC)(E)i...Let E be a holomophic vector bundle over a compact Astheno-Kähler manifold(M,ω).The authors would prove that E is a numerically flat vector bundle if E is pseudoeffective and the first Chern class c_(1)^(BC)(E)is zero.展开更多
目的评价CTA和DSA对Bühler弓(arc of Bühler,AOB)的检出率和临床意义。方法检索PubMed、Web of Science、Scopus、Embase、Google Scholar、CBM、CNKI、WanFang、VIP、Baidu Scholar数据库,纳入AOB相关的文献,采用Stata 17.0...目的评价CTA和DSA对Bühler弓(arc of Bühler,AOB)的检出率和临床意义。方法检索PubMed、Web of Science、Scopus、Embase、Google Scholar、CBM、CNKI、WanFang、VIP、Baidu Scholar数据库,纳入AOB相关的文献,采用Stata 17.0软件进行Meta分析。结果共计纳入11篇文献,包括研究对象3837例(含65例AOB)。AOB的总检出率为1.9%(0.8%~3.2%),CTA显示AOB的总检出率为2.0%(0.5%~4.3%),DSA显示AOB的总检出率为1.8%(0.5%~3.9%)。结论AOB是一种罕见的解剖学变异,在实施相关腹部手术时应考虑到AOB的存在,以免造成操作困难、腹腔脏器缺血或出血等并发症。展开更多
Recently,a description on a practicability of the Wöhler Curve Method for low-cycle fatigue of metals was given by the author.By the description and the low cycle fatigue test data of 16 MnR steel,it is important...Recently,a description on a practicability of the Wöhler Curve Method for low-cycle fatigue of metals was given by the author.By the description and the low cycle fatigue test data of 16 MnR steel,it is important to show that,for low cycle fatigue of metals,such a way that a stress-based intensity parameter calculated by the linear-elastic analysis is taken to be a stress intensity parameter,S,to establish a relationship between the stress intensity parameter,S,and the fatigue life,N,is practicable.In this paper,many metallic materials from the literature are given to show that the Wöhler Curve Method is well suitable for low-cycle fatigue analysis of metals.展开更多
设x:M→An+1是由定义在凸域ΩAn上的某局部严格凸函数xn+1=f(x1,...,xn)给出的超曲面.考虑Hessian度量 g =∑2fxixjdxidxj.若(M,g)是具有非负李奇曲率的紧致Hessian流形且仿射Khler-Scalar曲率为零,作者证明了如果Δρ≤nρ2...设x:M→An+1是由定义在凸域ΩAn上的某局部严格凸函数xn+1=f(x1,...,xn)给出的超曲面.考虑Hessian度量 g =∑2fxixjdxidxj.若(M,g)是具有非负李奇曲率的紧致Hessian流形且仿射Khler-Scalar曲率为零,作者证明了如果Δρ≤nρ2,则函数f一定是二次多项式,其中ρ=[det(fij)]-1n+2.展开更多
基金supported by the National key R&D Program of China(No.2020YFA0713100)the National Natural Science Foundation of China(No.12141104)the Jiangsu Funding Program for Excellent Postdoctoral Talent(No.2023ZB491).
文摘Let E be a holomophic vector bundle over a compact Astheno-Kähler manifold(M,ω).The authors would prove that E is a numerically flat vector bundle if E is pseudoeffective and the first Chern class c_(1)^(BC)(E)is zero.
文摘目的评价CTA和DSA对Bühler弓(arc of Bühler,AOB)的检出率和临床意义。方法检索PubMed、Web of Science、Scopus、Embase、Google Scholar、CBM、CNKI、WanFang、VIP、Baidu Scholar数据库,纳入AOB相关的文献,采用Stata 17.0软件进行Meta分析。结果共计纳入11篇文献,包括研究对象3837例(含65例AOB)。AOB的总检出率为1.9%(0.8%~3.2%),CTA显示AOB的总检出率为2.0%(0.5%~4.3%),DSA显示AOB的总检出率为1.8%(0.5%~3.9%)。结论AOB是一种罕见的解剖学变异,在实施相关腹部手术时应考虑到AOB的存在,以免造成操作困难、腹腔脏器缺血或出血等并发症。
文摘Recently,a description on a practicability of the Wöhler Curve Method for low-cycle fatigue of metals was given by the author.By the description and the low cycle fatigue test data of 16 MnR steel,it is important to show that,for low cycle fatigue of metals,such a way that a stress-based intensity parameter calculated by the linear-elastic analysis is taken to be a stress intensity parameter,S,to establish a relationship between the stress intensity parameter,S,and the fatigue life,N,is practicable.In this paper,many metallic materials from the literature are given to show that the Wöhler Curve Method is well suitable for low-cycle fatigue analysis of metals.
文摘设x:M→An+1是由定义在凸域ΩAn上的某局部严格凸函数xn+1=f(x1,...,xn)给出的超曲面.考虑Hessian度量 g =∑2fxixjdxidxj.若(M,g)是具有非负李奇曲率的紧致Hessian流形且仿射Khler-Scalar曲率为零,作者证明了如果Δρ≤nρ2,则函数f一定是二次多项式,其中ρ=[det(fij)]-1n+2.
