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241.
Christodoulos Athanasiadis Gary F. Roach Ioannis G. Stratis 《Mathematische Nachrichten》2003,250(1):3-16
A time domain analysis of the equations governing wave propagation in an unbounded chiral medium is presented by a spectral family approach and by a direct eigenfunction expansion using Beltrami–Moses fields. 相似文献
242.
GINDIKIN Simon 《中国科学A辑(英文版)》2006,49(11):1655-1661
We discuss some problems on rigidity of canonical realizations of complex homogeneous domains at ℂn
Dedicated to Professor Sheng GONG on the occasion of his 75th birthday 相似文献
243.
244.
John Michael Rassias Matina John Rassias 《Journal of Mathematical Analysis and Applications》2003,281(2):516-524
In 1941 Hyers solved the well-known Ulam stability problem for linear mappings. In 1951 Bourgin was the second author to treat this problem for additive mappings. In 1982-1998 Rassias established the Hyers-Ulam stability of linear and nonlinear mappings. In 1983 Skof was the first author to solve the same problem on a restricted domain. In 1998 Jung investigated the Hyers-Ulam stability of more general mappings on restricted domains. In this paper we introduce additive mappings of two forms: of “Jensen” and “Jensen type,” and achieve the Ulam stability of these mappings on restricted domains. Finally, we apply our results to the asymptotic behavior of the functional equations of these types. 相似文献
245.
In this paper, we establish sharp two-sided estimates for the Green functions of non-symmetric diffusions with measure-valued drifts in bounded Lipschitz domains. As consequences of these estimates, we get a 3G type theorem and a conditional gauge theorem for these diffusions in bounded Lipschitz domains.Informally the Schrödinger-type operators we consider are of the form L+μ⋅∇+ν where L is a uniformly elliptic second order differential operator, μ is a vector-valued signed measure belonging to Kd,1 and ν is a signed measure belonging to Kd,2. In this paper, we establish two-sided estimates for the heat kernels of Schrödinger-type operators in bounded C1,1-domains and a scale invariant boundary Harnack principle for the positive harmonic functions with respect to Schrödinger-type operators in bounded Lipschitz domains. 相似文献
246.
Potential Analysis - Assume that a bounded domain Ω??N (N ≥ 2) has the property that there exists a signed measure µ with compact support in Ω such that, for every... 相似文献
247.
C. -H. Lai 《Applied Mathematical Modelling》1992,16(12):638-644
For diffusion-dominated steady flows, classical second-order methods are usually used. A large number of iterations, and hence a long computing time, is required to solve the set of discretized equations using an iterative method. On the other hand, a direct solver is degraded because of the accumulation of round- off errors. For convection-dominated flows, first-order upwinding has been used over the past few decades but suffered from severe inaccuracy. In this paper we first discuss the accuracy improvement of solving a diffusion equation by shooting methods. We manage to achieve the theoretical order of accuracy as the mesh size decreases as far as single-precision arithmetic is concerned. We then discuss an application to the interface coupling of subproblems in the context of domain decomposition methods. Finally, we discuss high-order nonoscillatory solutions of a convection-diffusion equation based on shooting methods. 相似文献
248.
Inrecentyears,thequestionsofexistence,uniquenessandmultiplicityofsolutionstothe.problemhasbeenmuchinvestigated(see[l-ll]).WhereOisasmoothboundedregioninRN,N23and6istheLaplacianoperator.Thesolvabilityofboundaryvalueproblemdependsonthegrowthofthenonlinearityf(u)andontheregion,boundedorunbounded,unitballoranyotherregions.Wesaythatfunctionf(u)growssubcriticallyifthereexistsqe(l,'(N 2)/(N-2))suchthatliT32PIf(u)l/lulq相似文献
249.
Björn Gustafsson Mihai Putinar 《Journal of Mathematical Analysis and Applications》2007,328(2):995-1006
The analytic continuation of the exponential transform of a domain in Rn is proved under some global geometric assumptions on the boundary. Two approximation schemes of the continued transform (one based on a Taylor series truncation, the other on a global eigenfunction expansion) are also discussed. 相似文献