摘要:

AbstractIn the first part, basic properties of a class of functions (called Omega‐functions) are investigated, e.g. series representation, recurrence relation, asymptotic behavior. In the second part, beginning with Section 12, the solution of some versions of the diffusion equation by a series of Omega‐functions is treated. Omega‐functions may be used as auxiliary functions in the case of onedimensional non‐stationary diffusion under forced convection with or without removal

ISSN:0044-2267    

DOI:10.1002/zamm.19780580802

出版商:WILEY‐VCH Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractThe two‐fluid theory is used to analyze the wave motion of a fully ionized plasma under the gravitational field. For wave propagated in the direction of the gravitational force, the transverse waves are not affected by the gravitational force but the longitudinal waves are greatly affected by the gravitational force. There is a cut‐off frequency ωcsuch that all the longitudinal waves with frequency greater than ωcwill always be damped even for an ideal plasma of infinite electrical conduct

ISSN:0044-2267    

DOI:10.1002/zamm.19780580803

出版商:WILEY‐VCH Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractBy using a variational principle which is complementary to Hamilton's Principle, and by introducing new stress functions, the domain of application of stress functions has been extended to problems of elastodynamics. The Euler‐Lagrange equations associated with the new stress functions emerge as additional compatibility conditions involving the velocity fields. It is shown how by Judicial choice of the new stress functions various restricted motions may be analyse

ISSN:0044-2267    

DOI:10.1002/zamm.19780580804

出版商:WILEY‐VCH Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractThis paper deals with a formal extension of the Sih's fracture criterion so that the strain energy density factor is formulated both with the singular term and with the nonsingular terms of the solution in the elastic stress field near the crack tip. Thus, investigation of the direction of crack initiation leads to a two‐dimensional extreme value problem. In addition further statements on validity of the linear elastic behaviour of material in front of the crack tip are possibl

ISSN:0044-2267    

DOI:10.1002/zamm.19780580805

出版商:WILEY‐VCH Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractRecently Chandra and Gulati established duality theorems for the nondifferentiable fractional programming problem maximize<[cTx – (xTBx)1/2– α]/[eTx + (xTDx)1/2+ β] subject to Ax ≦ b, x≧. Here we treat the more general nonlinear fractional programming problem maximize [f(x) – (xTBx)1/2]/[g(x) + (xTDx)1/2] subject to h(x) ≦0, where f, g and h are differentiable, possibly nonlinear, functions. Necessary and sufficient conditions for optimality as well as appropriate duality theorems ar

ISSN:0044-2267    

DOI:10.1002/zamm.19780580806

出版商:WILEY‐VCH Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractFor a linear hyperbolic mixed boundary value problem frequently occurring in the engineering science, the existence and uniqueness of a solution are proved. The complete, self‐contained and analytical solution of the problem are explicitly given. With a view to a correct indication of the problem, only such boundary conditions are permitted which are not in contradiction with the defined compatibility condition

ISSN:0044-2267    

DOI:10.1002/zamm.19780580807

出版商:WILEY‐VCH Verlag    

年代:1978

数据来源: WILEY

ISSN:0044-2267    

DOI:10.1002/zamm.19780580808

出版商:WILEY‐VCH Verlag    

年代:1978

数据来源: WILEY

ISSN:0044-2267    

DOI:10.1002/zamm.19780580809

出版商:WILEY‐VCH Verlag    

年代:1978

数据来源: WILEY

ISSN:0044-2267    

DOI:10.1002/zamm.19780580810

出版商:WILEY‐VCH Verlag    

年代:1978

数据来源: WILEY

ISSN:0044-2267    

DOI:10.1002/zamm.19780580811

出版商:WILEY‐VCH Verlag    

年代:1978

数据来源: WILEY