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1.
FTL—空间上的Fuzzy连续线性算子   总被引:2,自引:0,他引:2  
本文将[1]中给出的fuzzy线性算子的定义作了适当的修改,使之更适合于在fuzzy拓扑线性空间(简称FTL-空间)中研究。我们证明了fuzzy线性算子的一个分解定理。在此基础上,研究了FTL-空间上fuzzy线性算子的连续性的一系列等价刻划,讨论了fuzzy线性算子的连续性与有界性的关系。最后,给出了FTL-空间上fuzzy连续线性算子族的一致有界原理。  相似文献   

2.
关于线性空间到欧氏空间的映射与线性映射   总被引:1,自引:0,他引:1  
文[2]推广了文[1]的全部定理,文[3]又推广了文[2]的全部定理,本文进一步推广了文[3]的全部定理,且证法简洁明快.本文约定,若V,ω是线性空间,则Vω表示V到ω的所有映射的集合,L(Vω)表示所有V到ω的线性映射的集合,L(V)表示V的所有线性变换的集合.本文总假定V是实数域上的线性空间,ω,ω1,ω2,…,ωn为欧氏空间.引理1 设A,B∈Vω,Ct,Dt∈Vωt(t=1,2,…,n),若α,β∈V有(Aα,Bβ)=∑nt=1(Ctα,Dtβ)(1)则x1,x2,…,xr, y1,y2,...,ys∈R(r,s∈N)α1,α2,…,αr, β1,β2,...,βs∈V,有(∑ri=1xiAαi,∑sj=1yjBβj)=∑nt=1(∑ri=1x…  相似文献   

3.
F连续线性映象空间   总被引:1,自引:0,他引:1  
本文采用(1)中给出的Fuzzy拓扑线性空间的定义,并利用Fuzzy拓扑线性空间的有关理论,对Fuzzy连续线性映象空间作了较深入的研究。  相似文献   

4.
文(4)中给出了X(L)上的模糊线性算子的定义。作为其特例,本文证明了LF拓扑线性空间上模糊线性泛函连续性的几个等价命题和模糊线性泛函的Hahn-Banach延拓定理,进而给出了LF拓扑线性空间上存在非零连续模糊线性泛函的一个充要条件。  相似文献   

5.
设 V、W是线性空间 ,本文用“VW”表示 V到 W的所有映射的集合 ,L( V)表示 V的所有线性变换的集合 ,L( VW)表示 V到 W的线性映射的集合。本文假定 V是实数域上的线性空间 ,W为欧氏空间。[1 ]证明了如下定理 :定理 1 [1]  设σ是欧氏空间 V的一个变换 ,φ∈ L ( V)且可逆 ,则对 α,β∈ V,均有 (σα,σβ) =( φα,φβ) ,当且仅当存在 V上正交变换 T,使 σ=Tφ。[2 ]推广 [1 ]的结果得 :定理 2 [2 ] 设 A,B∈ VV( 1 )若 B可逆 ,则有 α,β∈ V,( Aα,Aβ) =( Bα,Bβ) ,当且仅当存在 V的正交变换 T使 A=TB。( 2 )若 B…  相似文献   

6.
引入了幂空间、正则幂空间和一致幂空间概念,并讨论了其相关性质.  相似文献   

7.
引进了和内积空间没有相互包含关系的一类新空间:超积空间,进而研究了超积空间的性质.这类新的线性空间具有许多内积空间的重要性质,从而得到了线性空间一类新的度量刻画.  相似文献   

8.
证明了次子空间的几个不同形式定义的等价性,从不同侧面揭示了次子空间的本质特征,并且研究了次子空间的几何意义与在微积分学方面的应用。  相似文献   

9.
将粗糙集理论引入到线性空间与模糊线性空间中,分别给出了上粗与下粗线性空间及模糊上粗与模糊下粗线性空间的概念,并研究了它们的有关性质,获得了一系列有意义的结果。  相似文献   

10.
本文给出了Fuzzy拓扑线性空间的若干特征刻划,简化了判断Fuzzy拓扑线性空间的条件,研究了Fuzzy拓扑线性空间的层次结构,揭示了Fuzzy拓扑线性空间与分明拓扑线性空间的内在联系,得到了Fuzzy拓扑线性空间的“平移不变性”与“局部凸性”都是可截性质。  相似文献   

11.
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   

12.
13.
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   

14.
15.
We consider submanifolds of non-isotropic planes of the Grassman manifold of the pseudo-Euclidean space. We prove a theorem about the unboundedness of the sectional curvature of the submanifolds of the two-dimensional non-isotropic planes of the four-dimensional pseudo-Euclidean space with the help of immersion in the six-dimensional pseudo-Euclidean space of index 3. We also introduce a concept of the indicatrix of normal curvature and study the properties of this indicatrix and the Grassman image of the non-isotropic surface of the pseudo-Euclidean space. We find a connection between the curvature of the Grassman image and the intrinsic geometry of the plane. We suggest the classification of the points of the Grassman image.  相似文献   

16.
Conclusions A computational procedure based on a limiting state has been worked out which proposes the performance of tests of samples, small-scale models, and full-scale structures and a statistical analysis of the experimental data. Advantages of the method are shown in comparison with the computational method based on fracturing loads which pertain to estimating the accuracy of the computational scheme of structures and determining their safety coefficients. An optimality criterion is formulated within the framework of the method which is related to ensuring a maximum of the limiting (fracturing or critical) load with a constant mass of the structure.Applications of the method are given to estimation of the strength and stability of structures made out of polymeric and metal CM with the use of the Gol'denblat-Kopnov criterion and solutions based on linear shell theory. The conditions for realization of the optimality criterion of structures are determined. Recommendations are made for the rational reinforcement of structures made out of filamentary CM, and a procedure is proposed for the rational design of reinforced structures.As an example of the tests for stability of cylindrical shells made out of aluminum-magnesium alloy under external pressure, the legitimacy of the cause of the disagreement between the calculated and experimental critical loads, which consists of a discrepancy in the nature of wave formation at the instant of stability loss and initial imperfections, and the effectiveness of the computational method based on a limiting state are confirmed. Refined computational formulas for the critical loads of cylindrical shells made out of fiberglass, carbon fiber, and boraluminum under typical kinds of loading are proposed within the framework of the method and on the basis of an analysis of the results of tests, and a comparison is made of the effectiveness of the reinforcement of shells made out of aluminum-magnesium alloy and carbon fiber. The values of the safety coefficients of structures which guarantee their reliability are determined.Translated from Mekhanika Kompozitnykh Materialov, No. 2, pp. 262–271, March–April, 1980.  相似文献   

17.
The problem of the motion of a rigid body possessing a plane of symmetry over the surface of a three-dimensional sphere under the action of a spherical analogue of Newtonian gravitation forces is considered. Approaches to introducing spherical analogues of the concepts of centre of mass and centre of gravity are discussed. The spherical analogue of “satellite approach” in the problem of the motion of a rigid body in a central field, which arises on the assumption that the dimensions of the body are small compared with the distance to the gravitating centre, is studied. Within the framework of satellite approach, assuming plane motion of the body, the question of the existence and stability of steady motions is investigated. A spherical analogue of the equation of the plane oscillations of a body in an elliptic orbit is derived.  相似文献   

18.
19.
In this paper, a notion of Levitin–Polyak (LP in short) well-posedness is introduced for a vector optimization problem in terms of minimizing sequences and efficient solutions. Sufficient conditions for the LP well-posedness are studied under the assumptions of compactness of the feasible set, closedness of the set of minimal solutions and continuity of the objective function. The continuity assumption is then weakened to cone lower semicontinuity for vector-valued functions. A notion of LP minimizing sequence of sets is studied to establish another set of sufficient conditions for the LP well-posedness of the vector problem. For a quasiconvex vector optimization problem, sufficient conditions are obtained by weakening the compactness of the feasible set to a certain level-boundedness condition. This in turn leads to the equivalence of LP well-posedness and compactness of the set of efficient solutions. Some characterizations of LP well-posedness are given in terms of the upper Hausdorff convergence of the sequence of sets of approximate efficient solutions and the upper semicontinuity of an approximate efficient map by assuming the compactness of the set of efficient solutions, even when the objective function is not necessarily quasiconvex. Finally, a characterization of LP well-posedness in terms of the closedness of the approximate efficient map is provided by assuming the compactness of the feasible set.  相似文献   

20.
The motion of a satellite about its centre of mass in a central Newtonian gravitational field is investigated. The satellite is considered to be a dynamically symmetrical rigid body. It is assumed that the ratio of the polar and equatorial principal central moments of inertia of the satellite is 4/3, or close to this. The orbit of the centre of mass is elliptic, and the orbit eccentricity is assumed to be small. In the limit case, when the orbit of the centre of mass is circular, a steady motion exists (corresponding to relative equilibrium of the satellite in the orbital system of coordinates) in which the axis of dynamic symmetry is directed along the velocity vector of the centre of mass of the satellite; here, the frequencies of the small linear oscillations of the axis of symmetry are equal or close to one another. But in an elliptic orbit of small eccentricity, multiple 1:1:1 resonance occurs in this case, as the oscillation frequencies mentioned are equal or close to the frequency of motion of the centre of mass of the satellite in orbit. The non-linear problem of the existence, bifurcations and stability of periodic motions of the satellite with a period equal to the rotation period of its centre of mass in orbit is investigated.  相似文献   

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