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1.
本文研究了diffeological空间范畴中光滑映射的分解问题.利用经典同伦论中映射分解的方法,获得了任何一个光滑映射都可以分解为一个光滑同伦等价和光滑纤维化或光滑上纤维化的复合的结果,推广了拓扑空间范畴中的相关结果.  相似文献   

2.
在一致凸一致光滑的Banach空间中,引进了一个新的修正的Halpern迭代序列,并证明了该迭代序列关于α-逆强增生算子的强收敛性,所得结果把其他一些相关的近代结果从2-一致光滑Banach空间推广到一致光滑Banach空间,并且证明方法也不相同.  相似文献   

3.
局部标准2-torus作用和带角流形   总被引:1,自引:1,他引:0  
给出了光滑闭流形上的光滑2-torus作用是局部标准的一个充要条件,即其轨道空间是好的带角流形,并且对轨道空间中的每一个点,其迷向子群的秩等于该点的余维数.  相似文献   

4.
刘西民 《数学季刊》2000,15(1):9-13
设X是单连通光滑闭4-流形,有限群G光滑作用于X,令p:E→X是X上具有光滑G作用的SU(2)从且p是一个G映射.本文研究了丛E上等模空间M^G和商丛E’→X’上的关键空间之间的关系,并讨论了不变模空间的紧致化。  相似文献   

5.
给出了Banach空间凸性特征与光滑模的一个关系。  相似文献   

6.
非常极凸空间的推广及其对偶概念   总被引:1,自引:1,他引:0  
本文研究了k非常极凸和k非常极光滑空间的问题.利用Banach空间理论的方法,证明了k非常极凸空间和k非常极光滑空间是一对对偶概念,并且k非常极凸空间(k非常极光滑空间)是严格介于k一致极凸空间和k非常凸空间(k一致极光滑空间和k非常光滑空间)之间的一类新的Banach空间,得到了k非常极凸空间和k非常极光滑空间的若干等价刻画以及k非常极凸(k非常极光滑性)与其它凸性(光滑性)之间的蕴涵关系,推广了非常极凸空间和非常极光滑空间,完善了k非常极凸空间及其对偶空间的研究.  相似文献   

7.
平的Banach空间   总被引:1,自引:0,他引:1  
韩景銮  黎永锦 《数学进展》1995,24(3):254-256
本文定义了平的Banach空间,证明了平的Banach的空间X的共轭空间X没有非常光滑点,而S(X)的非光滑点在S(X)是稠密的,同时还给出X具有粗范数的一个充分条件。  相似文献   

8.
给定一个实Jacobi群G,我们考虑G的一个Hilbert空间连续表示的范畴,和G的一个Frechet空间光滑表示的范畴.由Mackey理论,它们分别等价于某个实约化群三的两个表示范畴.在这些范畴等价下,我们证明G,表示的光滑化函子和三一表示的光滑化函子是相容的.利用Casselman—Wallach的实约化群光滑表示理论,我们对G的一类光滑表示定义了广义的矩阵系数.为了证明Fourier—Jacobi模型的重数一定理,我们还提出了实Jacobi群的Gelfand—Kazhdan判别法.  相似文献   

9.
研究了局部凸空间的某些几何性质,得到了局部凸空间为一致光滑的一个充分必要条件及局部凸空间为一致凸的若干等价条件,最后讨论了局部凸空间的有关逼近问题。  相似文献   

10.
K-强凸空间的一些性质   总被引:4,自引:0,他引:4  
结合Banach空间的Drop性,利用K维体积给出了K—强凸空间的一个新的定义,同时也给出了K—强光滑空间定义的K维体积表示,然后利用单位圆的切片证明了K—强凸空间是自反空间,进而证明了K—强凸空间与K—强光滑空间是一对对偶空间.最后利用Drop性的切片描述证明了K—强凸空间具有Drop性.  相似文献   

11.
In this paper, we give an operator parameterization for the set of dilations of a given pair of dual g-frames and the set of dilations of pairs of dual g-frames of a given g-frame. In particular, for the dilations of a given pair of dual g-frames, we introduce the concept of joint complementary g-frames and prove that the joint complementary g-frames of a pair of dual g-frames are unique in the sense of joint similarity, which then helps to obtain a sufficient condition such that the complementary g-frames of a g-frame are unique in the sense of similarity and show that the set of dilations of a given dual g-frame pair are parameterized by a set of invertible diagonal operators. For the dilations of pairs of dual g-frames, we prove that the set of dilations of pairs of dual g-frames are parameterized by a set of invertible upper triangular operators.  相似文献   

12.
Problems of the joint optimization of the shape and distribution along the meridian of the thickness of membrane shells of revolution under the action of axisymmetric loads are considered, taking account of the constraints concerning the strength of the shell and the volume of its cavity. General formulations of problems of the optimal design of shells of revolution are given and the optimal shape of a shell and the corresponding thickness distribution are investigated. Results of the exact solution of problems of the optimal design of closed shells of revolution when there is an internal pressure are presented. The simultaneous introduction of two control functions, describing the shape of the shell and the distribution of its thickness, not only ensures a substantial reduction in the mass of a shell but also leads to significant mathematical simplifications, which enable the solution of the optimization problem being considered to be obtained in an analytical form.  相似文献   

13.
The theory of long-term damageability of a homogeneous material is generalized to the case of an orthotropic fibrous composite material with a stochastic structure. Equations of mechanics of microinhomogeneous media of this structure form the base of the theory. The process of damage of components of a composite is modeled by the formation of stochastically located micropores. The criterion of fracture of a unit microvolume is characterized by its long-term strength determined by the dependence of the time of brittle fracture on the degree of closeness of the equivalent stress to its limit value, which characterizes the short-term strength on the basis of the Huber–von Mises criterion accepted as an arbitrary function of coordinates. Efficient deformation properties and the stress-strain state of an orthotropic fibrous composite with microdamages in components are determined on the base of stochastic equations of elasticity of orthotropic media. For given macrostresses and macrostrains and an arbitrary moment of time, balance equations of damage (porosity) of components are formulated. On the basis of the iteration method, we construct algorithms for calculating dependences of microdamage of components of an orthotropic fibrous material on time and dependences of macrostresses or macrostrains on time and obtain the corresponding curves for the case of a bounded function of the long-term microstrength, which is approximated by an exponential law.  相似文献   

14.
研究了区间数的绝对值和区间值函数的极限问题.首先,讨论了区间数的H-差的性质,得到了H-差的两个运算法则;然后,给出了区间数的绝对值概念,并讨论了区间数绝对值的性质;最后,借助区间数的H-差和绝对值的概念,建立了区间值函数极限概念的一种新的表达方式,给出了极限存在的充分必要条件,证明了极限值的唯一性及对加法运算和数乘运算的封闭性.  相似文献   

15.
For a class of entire functions we study the problem of estimation of the order of growth of functions on the real axis. This problem is important for the justification of the integral representation of bounded solutions to certain partial differential equations considered in other papers of the authors. In order to obtain an estimate of the order of growth of a function on the real axis, we use the method of differential equations. The method is based, on one hand, on the construction of a system of first-order ordinary differential equations whose solution is a vector function of traces of function and its derivatives on the real axis. On the other hand, under the respective change of variables in the system of equations, we obtain an estimate of the solution to the system of equations for a large positive values of the argument. The obtained estimate is non-trivial and shows the way a complex parameter of a power series affects the order of growth of a function.  相似文献   

16.
17.
We survey the known hyperovals in . We then survey the relationship of the study of configurations of ovals in called augmented fans to that of ovoids of , flocks of the quadratic cone of , flocks of a translation oval cone of and spreads of certain generalised quadrangles of order. We also consider the configurations of ovals in called herds and their relationship with flocks of the quadratic cone of.  相似文献   

18.
19.
The paper is devoted to the solution of straight and inverse geometrical tasks of five link mechanism with two degrees of freedom. The solution of the mentioned problem is very important in order to determine kinematic parameters of actuators. The problem can be divided into two parts. The first part is considered when we are given the coordinates of the output link of the mechanism and the necessity arises of determining the angles of rotation of actuators. On the other hand, it is very important to determine the position of the output link when the angles of rotation of the actuators are known. Here we consider that the mechanism is composed only of five classes of rotating kinematic pairs and the actuators are situated at the junctions of frames and links of the examined mechanism. The solution of the said problem is based on utilization of homogenous coordinates. On the basis of the obtained equations of motion, one can calculate the trajectories of motion of the output link as well angles of rotation of the actuators by taking into consideration preliminary given kinematic parameters of the mechanism. Here we also obtain equations for calculating values of speed and acceleration of the links of the mechanism. The calculations differ from known methods in simplicity and high performance, which would be useful for programming actuators mounted in the joints of the linkage.  相似文献   

20.
我国医疗费用增长与医疗设备投入的相关性研究   总被引:3,自引:0,他引:3  
近年来我国卫生总费用占GDP的比例增长很快,而在卫生费用结构上则发生政府投入下降和个人支出的上升。本文采集了大量的统计数据,采用统计相关性研究的方法,论证了医疗设备规模的不断扩大是导致医疗费用上升的主要因素之一;医疗设备的快速增长与医院维修费用投入的增长直接相关,而引起医疗设备维修大量投入的主要原因则是故障期内医疗设备的非正常闲置。本文通过对个人卫生费用的上升、医疗设备规模的扩大及其医疗设备维修投入费用增加相关性的分析,说明了在这种关系下,十分有必要研究医院医疗设备维修体系,以在卫生投入和患者权益上达到平衡。  相似文献   

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