共查询到20条相似文献,搜索用时 31 毫秒
1.
R. R. Salimov 《Siberian Mathematical Journal》2012,53(4):739-747
Under study is the class of ring Q-homeomorphisms with respect to the p-module. We establish a criterion for a function to belong to the class and solve a problem that stems from M. A. Lavrentiev [1] on the estimation of the measure of the image of the ball under these mappings. We also address the asymptotic behavior of these mappings at a point. 相似文献
2.
F. J. Schuurmann P. R. Krishnaiah A. K. Chattopadhyay 《Journal of multivariate analysis》1973,3(4):445-453
In this paper, the authors cosider the derivation of the exact distributions of the ratios of the extreme roots to the trace of the Wishart matrix. Also, exact percentage points of these distributions are given and their applications are discussed. 相似文献
3.
N. K. Bakirov 《Journal of Mathematical Sciences》1989,44(4):425-432
One investigates the asymptotic properties of the quantile test, similar to the properties of the Pearson's chi-square test of fit.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 153, pp. 5–15, 1986.The author is grateful to D. M. Chibisov for useful remarks. 相似文献
4.
Michael Coons 《The Ramanujan Journal》2013,30(1):39-65
Let $\mathcal{G}(z):=\sum_{n\geqslant0} z^{2^{n}}(1-z^{2^{n}})^{-1}$ denote the generating function of the ruler function, and $\mathcal {F}(z):=\sum_{n\geqslant} z^{2^{n}}(1+z^{2^{n}})^{-1}$ ; note that the special value $\mathcal{F}(1/2)$ is the sum of the reciprocals of the Fermat numbers $F_{n}:=2^{2^{n}}+1$ . The functions $\mathcal{F}(z)$ and $\mathcal{G}(z)$ as well as their special values have been studied by Mahler, Golomb, Schwarz, and Duverney; it is known that the numbers $\mathcal {F}(\alpha)$ and $\mathcal{G}(\alpha)$ are transcendental for all algebraic numbers α which satisfy 0<α<1. For a sequence u, denote the Hankel matrix $H_{n}^{p}(\mathbf {u}):=(u({p+i+j-2}))_{1\leqslant i,j\leqslant n}$ . Let α be a real number. The irrationality exponent μ(α) is defined as the supremum of the set of real numbers μ such that the inequality |α?p/q|<q ?μ has infinitely many solutions (p,q)∈?×?. In this paper, we first prove that the determinants of $H_{n}^{1}(\mathbf {g})$ and $H_{n}^{1}(\mathbf{f})$ are nonzero for every n?1. We then use this result to prove that for b?2 the irrationality exponents $\mu(\mathcal{F}(1/b))$ and $\mu(\mathcal{G}(1/b))$ are equal to 2; in particular, the irrationality exponent of the sum of the reciprocals of the Fermat numbers is 2. 相似文献
5.
In [2] it was shown with reference to the cylindrical bending of a plate that the Kirchhoff-Love hypothesis is asympototically accurate for determining the critical load irrespective of the properties of the material. However, the question of the dependence of the critical load on the material properties was left unexplored. This question is now numerically investigated. Curves characterizing the variation of the critical load with relative shear modulus are presented.Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Mekhanika Polimerov, Vol. 5, No. 2, pp. 355–357. March–April, 1969. 相似文献
6.
V. Ya. Tereshchenko 《Journal of Applied Mathematics and Mechanics》1987,51(6):785-792
An algorithm is proposed for solving the Signorini problem /1/ in the formulation of a unilateral variational problem for the boundary functional in the zone of possible contact /2/. The algorithm is based on a dual formulation of Lagrange maximin problems for whose solution a decomposition approach is used in the following sense: a Ritz process in the basis functions that satisfy the linear constraint of the problem, the differential equation in the domain, is used in solving the minimum problem (with fixed Lagrange multipliers); the maximum problem is solved by the method of descent (a generalization of the Frank-Wolf method) under convexity constraints on the Lagrange multipliers. The algorithm constructed can be conisidered as a modification of the well-known algorithm to find the Udzawa-Arrow-Hurwitz saddle points /3, 4/. The convergence of the algorithm is investigated. A numerical analysis of the algorithm is performed in the example of a classical contact problem about the insertion of a stamp in an elastic half-plane under approximation of the contact boundary by isoparametric boundary elements. The comparative efficiency of the algorithm is associated with the reduction in the dimensionality of the boundary value problem being solved and the possibility of utilizing the calculation apparatus of the method of boundary elements to realize the solution. 相似文献
7.
用常微分方程模型分析预防和隔离措施对SARS发病率的影响 总被引:2,自引:2,他引:0
通过建立常微分方程模型 ,分析了预防和隔离措施对 SARS发病率的影响 ,并把计算结果与实际统计数据进行了比较 ,结果表明 ,及时高效的预防和隔离措施能够有效地控制 SARS的传播 . 相似文献
8.
Algebra and Logic - In a first order language we interpret the action of the monoid M of embeddings of (?,<) on the set ? inside (M,°). A similar result is proved for the... 相似文献
9.
Angelo Miele 《Journal of Optimization Theory and Applications》1967,1(1):70-82
This paper considers the minimization of the product of the powers ofn integrals, each of which depends on a functiony(x) and its derivative
. The necessary conditions for the extremum are derived within the frame of the Mayer-Bolza formulation of the calculus of variations, and it is shown that the extremal arc is governed by a second-order differential equation involvingn undetermined multipliers related to the unknown values of the integrals. After the general solution is combined with the definitions of the multipliers and the end conditions, a system ofn+2 algebraic equations is obtained; it involvesn+2 unknowns, that is, then undetermined multipliers and two integration constants.The procedure discussed here can be employed in the study of shapes which are aerodynamically optimum at supersonic, hypersonic, and free-molecular flow velocities, that is, wings and fuselages having the maximum lift-to-drag ratio or the minimum drag. The problem of a slender body of revolution having the minimum pressure drag in Newtonian hypersonic flow is developed as an example. First, a general solution is derived for any pair of conditions imposed on the length, the thickness, the wetted area, and the volume. Then, a particular case is treated, that in which the thickness and the wetted area are given, while the length and the volume are free; the shape minimizing the pressure drag is a cone.This research, supported by the Office of Scientific Research, Office of Aerospace Research, United States Air Force, Grant No. AF-AFOSR-828-67, is a condensed version of the investigation described in Ref. 1. The author is indebted to Messrs. H. Y. Huang, J. C. Heideman, and J. N. Damoulakis for analytical and numerical assistance. 相似文献
10.
Giovannia Cimatti 《Applicable analysis》2013,92(3-4):407-423
The stability of the stationary solution of the thermistor problem 1s proved using a Liapunov functional for a class of physically relevant electrical conductivity. 相似文献
11.
Vilks Yu. K. Saulgozis Yu. Zh. Balodis A. A. Knets I. V. Yanson Kh. A. 《Mechanics of Composite Materials》1974,10(5):771-778
Mechanics of Composite Materials - A method is proposed for determining the propagation velocity and coefficient of attenuation of ultrasonic vibrations in both the whole diaphysis of the human... 相似文献
12.
A method is proposed for estimating the thermal-conductivity coefficients of orthotropic composite glass-reinforced plastics with a structure composed of continually repeating units, in which the contours of the reinforcing elements can be described by a sinusoidal law. The arguments in the formulas are the relative content and thermophysical characteristics of the components and the parameters of the microstructure of the materials considered.Mekhanika Polimerov, Vol. 4, No. 1, pp. 18–23, 1968 相似文献
13.
N. N. Ural'tseva 《Journal of Mathematical Sciences》1989,45(3):1181-1191
For the equation Au=f(x) in the domain Rn, where A is a linear second-order elliptic operator, under conditions of Signorini type on the boundary of the domain , one proves the boundedness of the Hölder continuity of the first derivatives of the solution under the assumption that f Lq(), q>n. The results are applied to the investigation of the regularity of the solutions of variational inequalities in the case of quasilinear operators.Translated from Problemy Matematicheskogo Analiza, No. 10, pp. 92–105, 1986. 相似文献
14.
When the Laplace transform is inverted numerically, the original function is sought in the form of a series in the Laguerre polynomials. To accelerate the convergence of this series, the Euler-Knopp method is used. The techniques for selecting the optimal value of the parameter of the transform on the real axis and in the complex plane are proposed. 相似文献
15.
Leonid Tolmatz 《Journal of Mathematical Analysis and Applications》2005,304(2):668-682
The double Laplace transform of the distribution function of the integral of the positive part of the Brownian bridge was determined by M. Perman and J.A. Wellner, as well as the moments of this distribution. The purpose of the present paper is to determine the asymptotics of this distribution for large values of the argument, and the corresponding asymptotics of the moments. 相似文献
16.
LetT be a positive linear operator on the Banach latticeE and let (S
n
) be a sequence of bounded linear operators onE which converge strongly toT. Our main results are concerned with the question under which additional assumptions onS
n
andT the peripheral spectra (S
n
) ofS
n
converge to the peripheral spectrum (T) ofT. We are able to treat even the more general case of discretely convergent sequences of operators. 相似文献
17.
多晶体光滑表面疲劳微裂纹形核机理研究 总被引:1,自引:0,他引:1
建立晶体学模型来研究多晶体承受均匀外载时光滑表面疲劳微裂纹形核的机理.由于晶粒取向的不相同,即使承受均匀外载,多晶体内将产生不均匀的应力,变形也不均匀A·D2在疲劳载荷的作用下,表面粗糙度随疲劳周次逐渐增加,变形逐渐集中到若干部位,即局部化,形成微裂纹. 相似文献
18.
V. V. Kuznetsov 《Journal of Mathematical Sciences》1986,32(5):483-485
One obtains conditions for the existence and uniqueness of the solution of the continuation of the boundary layer near a solid wall in the case when the pressure gradient Px is positive and satisfies one of the inequalities pxpx(0).Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Maternaticheskogo Instituts im. V. A. Steklova AN SSSR, Vol. 138, pp. 86–89, 1984.The author is grateful to V. V. Pukhnachev for his assistance and also to N. V. Khusnutdinova for useful remarks. 相似文献
19.
Yu. Zh. Saulgozis I. V. Knet-s Kh. A. Yanson G. O. Pfafrod 《Mechanics of Composite Materials》1971,7(5):837-842
The elastic, deformation, and strength properties of six different zones of the cross section of the diaphysis of the human tibia have been experimentally investigated. It is shown that when the compact bone tissue is stressed in tension all these properties differ significantly from zone to zone. The greatest values of the initial modulus of elasticity and the tensile strength correspond to the frontal-outer zones of the bone. The nonlinear stress-strain curves are analytically approximated. The secant and tangent moduli are shown to depend on the stress intensity.Institute of Polymer Mechanics, Academy of Sciences of the Latvian SSR, Riga. Translated from Mekhanika Polimerov, No. 5, pp. 940–946, September–October, 1971. 相似文献
20.
Jennifer Biermann 《代数通讯》2013,41(8):3665-3681
We study the minimal free resolution of the edge ideal of the complement of the n-cycle for n ≥ 4 and construct a regular cellular complex which supports this resolution. 相似文献