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991.
岩土强度与变形关系的理论剖析 总被引:1,自引:0,他引:1
深入浅出地阐述了岩土强度与变形关系,并对一些令人困惑的问题进行了讨论和作出可能的解释。 相似文献
992.
V. V. Ivanenko Yu. G. Voloshina M. V. Okhrimenko L. K. Patrilyak K. I. Patrilyak 《Theoretical and Experimental Chemistry》2009,45(3):198-202
Along with oxidation of hydrogen-containing coke structures, we have observed oxidation of compact accumulations of hydrogen-free
coke and as a result we can quantitatively differentiate between outer-surface and intraporous burned coke, and the intraporous
coke in turn can be quantitatively distributed over the different elements of the zeolite structures.
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 45, No. 3, pp. 185–189, May–June, 2009. 相似文献
993.
On convergence properties of a least-distance programming procedure for minimization problems under linear constraints 总被引:3,自引:0,他引:3
G. L. Xue 《Journal of Optimization Theory and Applications》1986,50(2):365-370
In Ref. 1, Bazaraa and Goode provided an algorithm for solving a nonlinear programming problem with linear constraints. In this paper, we show that this algorithm possesses good convergence properties.This paper was written under the guidance of Associate Professor C. Y. Wang. The author takes great pleasure in thanking him. 相似文献
994.
F. Bavaud 《Journal of statistical physics》1986,45(1-2):171-181
New expressions for the elastic moduli of a classical system are derived. They involve only the two-point correlation function and the derivative of the onepoint correlation function, both only on the boundary of the system. These expressions, valid for any interaction derivable from a potential, are proved from a mechanical point of view by generalizing the virial theorem of Clausius, and from a statistical point of view by a direct method that constitutes an alternative to Green's dilatation method. 相似文献
995.
In this paper, we examine a joint lot-sizing and process investment problem with random yield and backorders. We allow for inspection and develop stochastic models which provide the optimal inspection and lot-sizing policy as well as the optimal process investment for variance reduction. The process quality loss profile around the target is captured via a modification of the Reflected Normal loss function. We conduct numerical experiments assuming that the proportion of defectives follows a Uniform distribution while the process quality characteristic follows either a Normal or Uniform distribution. We also develop closed-form solutions that depend on at most the first two moments of any general probability distribution of defective units and which allow us to examine the nature of optimal policies. We demonstrate via numerical experiments the value of our integrated approach for jointly determining optimal inventory, inspection, and investment policies. Overall, our models and analyses provide some interesting insights into this reasonably complex inventory-quality problem and open up several avenues for future work in this area. 相似文献
996.
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
997.
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
998.
P. A. Kendall N. J. Mason 《Journal of Electron Spectroscopy and Related Phenomena》2001,120(1-3):27-31
Electron energy loss spectroscopy (EELS) has been used to study the photo-absorption spectrum of trifluoromethyl sulphur pentafluoride (SF5CF3) for the first time. Comparison is made with the EELS spectrum of sulphur hexafluoride (SF6). The photolysis of the compound is discussed with relevance to estimated lifetimes in the atmosphere. It is estimated that the lifetime of SF5CF3 is of the order of 1000 years. 相似文献
999.
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
1000.
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