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941.
N. Chakraborti B. Siva Kumar V. Satish Babu S. Moitra A. Mukhopadhyay 《Applied Mathematical Modelling》2008
A new genetic algorithms based multi-objective optimization algorithm (NMGA) has been developed during study. It works on a neighborhood concept in the functional space, utilizes the ideas on weak dominance and ranking and uses its own procedures for population sizing. The algorithm was successfully tested with some standard test functions, and when applied to a real-life data of the hot-rolling campaign of an integrated steel plant, it outperformed another recently developed multi-objective evolutionary algorithm. 相似文献
942.
Luděk Zajíček 《Czechoslovak Mathematical Journal》2008,58(3):849-864
Properties of Lipschitz and d.c. surfaces of finite codimension in a Banach space and properties of generated σ-ideals are studied. These σ-ideals naturally appear in the differentiation theory and in the abstract approximation theory. Using these properties, we
improve an unpublished result of M. Heisler which gives an alternative proof of a result of D. Preiss on singular points of
convex functions. 相似文献
943.
Luis Velázquez 《Journal of Functional Analysis》2008,254(4):954-986
We present an operator theoretic approach to orthogonal rational functions based on the identification of a suitable matrix representation of the multiplication operator associated with the corresponding orthogonality measure. Two alternatives are discussed, leading to representations which are linear fractional transformations with matrix coefficients acting on infinite Hessenberg or five-diagonal unitary matrices. This approach permits us to recover the orthogonality measure throughout the spectral analysis of an infinite matrix depending uniquely on the poles and the parameters of the recurrence relation for the orthogonal rational functions. Besides, the zeros of the orthogonal and para-orthogonal rational functions are identified as the eigenvalues of matrix linear fractional transformations of finite Hessenberg or five-diagonal matrices. As an application we use operator perturbation theory results to obtain new relations between the support of the orthogonality measure and the location of the poles and parameters of the recurrence relation for the orthogonal rational functions. 相似文献
944.
Radu Ioan Bo? Sorin-Mihai Grad 《Journal of Mathematical Analysis and Applications》2008,337(2):1315-1325
We give some necessary and sufficient conditions which completely characterize the strong and total Lagrange duality, respectively, for convex optimization problems in separated locally convex spaces. We also prove similar statements for the problems obtained by perturbing the objective functions of the primal problems by arbitrary linear functionals. In the particular case when we deal with convex optimization problems having infinitely many convex inequalities as constraints the conditions we work with turn into the so-called Farkas-Minkowski and locally Farkas-Minkowski conditions for systems of convex inequalities, recently used in the literature. Moreover, we show that our new results extend some existing ones in the literature. 相似文献
945.
During the last years both Erd?s space and complete Erd?s space were topologically characterized by Dijkstra and van Mill. Applications include results about Erd?s type spaces in ?p-spaces as well as results about Polishable ideals on ω. We present an unifying theorem in terms of sets with a reflexive relation that among other things contains these apparently dissimilar results as special cases. 相似文献
946.
Abstract We develop a modular landscape model for the mountain pine beetle (Dendroctonus ponderosae Hopkins) infestation of a stage‐structured forest of lodgepole pine (Pinus contorta Douglas). Beetle attack dynamics are modeled using response functions and beetle movement using dispersal kernels. This modeling technique yields four model candidates. These models allow discrimination between four broad possibilities at the landscape scale: whether or not beetles are subject to an Allee effect at the landscape scale and whether or not host selection is random or directed. We fit the models with aerial damage survey data to the Sawtooth National Recreation Area using estimating functions, which allows for more rapid and complete parameter determination. We then introduce a novel model selection procedure based on facial recognition technology to compliment traditional nonspatial selection metrics. Together with these we are able to select a best model and draw inferences regarding the behavior of the beetle in outbreak conditions. 相似文献
947.
Tülin Coşkun 《Proceedings Mathematical Sciences》2000,110(4):357-362
In this work we obtain, under suitable conditions, theorems of Korovkin type for spaces with different weight, composed of
continuous functions defined on unbounded regions. These results can be seen as an extension of theorems by Gadjiev in [4]
and [5]. 相似文献
948.
方征 《大庆师范学院学报》2007,27(4):141-144
混沌理论已运用到教育领域。学校面临外部环境复杂性、学校管理目标的多维性、学校内部存在自发的混沌行为,决定学校管理中必然存在混沌现象。对学校的计划、组织、领导和控制这四大管理职能中混沌现象进行审视,并利用混沌管理理论与方法提出相应绩效改进措施。 相似文献
949.
Gu-Qiang Li 《Theoretical and Mathematical Physics》2008,157(1):1496-1502
We use the brick-wall method to investigate the thermodynamic quantities around a charged dilaton black hole. We show that
all the thermodynamic quantities contain two terms: the first term has exactly the same form as in a flat space-time, but
the second term depends explicitly on the spin of the fields and therefore cannot be neglected.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 157, No. 1, pp. 154–160, October, 2008. 相似文献
950.
In this article,the authors obtain an integral representation for the relaxation of the functional
F(x,u,Ω):={∫^f(x,u(x),εu(x))dx Ω if u∈W^1,1(Ω,R^N), +∞ otherwise, in the space of functions of bounded deformation,with respect to L^1-convergence.Here Eu represents the absolutely continuous part of the symmetrized distributional derivative Eu.f(x,p,ξ)satisfying weak convexity assumption. 相似文献
F(x,u,Ω):={∫^f(x,u(x),εu(x))dx Ω if u∈W^1,1(Ω,R^N), +∞ otherwise, in the space of functions of bounded deformation,with respect to L^1-convergence.Here Eu represents the absolutely continuous part of the symmetrized distributional derivative Eu.f(x,p,ξ)satisfying weak convexity assumption. 相似文献