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991.
This paper studies online scheduling problems with reassignment on two identical machines. We can reassign some jobs under certain rules after all the jobs have been assigned. Three different versions are studied and optimal algorithms are proposed. 相似文献
992.
The Fisher information of the classical orthogonal polynomials with respect to a parameter is introduced, its interest justified and its explicit expression for the Jacobi, Laguerre, Gegenbauer and Grosjean polynomials found. 相似文献
993.
The dependence of the linear stability of two-time-level finite-difference semi-implicit schemes on the choice of reference temperature profile is studied. Particular vertical profiles of the temperature are considered to derive analytical conditions of stability. Analysis is made for general form of different model parameters such as the number of vertical levels and their distribution, the time step size, and the values of the viscosity coefficients. The derived conditions of stability are more restrictive than those for three-time-level schemes, but obtained necessary and sufficient condition for constant vertical lapse rates of the temperature has the form frequently applied to three-time-level schemes: the basic temperature profile should be warmer than the actual one. Performed numerical experiments show that the last restriction is neither necessary nor sufficient condition of stability for general temperature profiles. 相似文献
994.
A. Birštunas 《Lithuanian Mathematical Journal》2008,48(2):174-187
We study sequent calculus for multi-modal logic K D45n and its complexity. We introduce a loop-check free sequent calculus. Loop-check is eliminated by using the marked modal operator
□i•, which is used as an alternative to sequents with histories ([8], [3], [5]). All inference rules are invertible or semi-invertible.
To get this, we use or branches beside common and branches. We prove the equivalence between known sequent calculus and our newly introduced efficient sequent calculus.
We concentrate on the complexity analysis of the introduced sequent calculus for multi-modal logic K D45n. We prove that the space complexity of the given calculus is polynomial (O(l
3)). We show the maximum height of the constructed derivation tree that leads to the reduction of the time and space complexity.
We present a decision algorithm for multi-modal logic K D45n and some nontrivial examples to improve the introduced loop-check free sequent calculus. 相似文献
995.
996.
In this paper tests are derived for testing neighborhood hypotheses for the one- and multi-sample problem for functional data. Our methodology is used to generalize testing in projective shape analysis, which has traditionally involving data consisting of finite number of points, to the functional case. The one-sample test is applied to the problem of scene identification, in the context of the projective shape of a planar curve. 相似文献
997.
We consider the shape-topology optimization of the Navier–Stokes problem. A new algorithm is proposed based on the variational level set method. By this algorithm, a relatively smooth evolution can be maintained without re-initialization and drastic topology change can be handled easily. Finally, the promising features of the proposed method are illustrated by two benchmark examples. 相似文献
998.
Oscar García Josep Vehí Jose Campos e Matos António Abel Henriques Joan Ramon Casas 《Journal of Computational and Applied Mathematics》2008
An efficient health monitoring system for damage detection in civil engineering structures using on-line monitoring data is being developed to identify any possible damage in short time. The present work is based on the treatment of uncertainties, which is one of the basic common difficulties faced when modelling structures. A methodology, based on interval analysis (IA) theory [R.E. Moore, Interval Analysis, Prentice-Hall, Englewood Cliffs, NJ, 1966] applied to a numerical constraint satisfaction problem (CSP) [J.R. Casas, J.C. Matos, J.A. Figueiras, J. Vehí, O. García, P. Herrero, Bridge monitoring and assessment under uncertainty via interval analysis, in: Ninth International Conference On Structural Safety And Reliability—ICOSSAR2005, 2005. pp. 487–494], is implemented in the damage detection [J.R. Casas, J.C. Matos, J.A. Figueiras, J. Vehí, O. García, P. Herrero, Bridge monitoring and assessment under uncertainty via interval analysis, in: Ninth International Conference On Structural Safety And Reliability—ICOSSAR2005, 2005. pp. 487–494] and modelling system of a long-term monitoring project in order to achieve such an objective. An algorithm is being developed for using such methodology with the obtained data. 相似文献
999.
Miguel A. Goberna Mercedes Larriqueta Virginia N. Vera de Serio 《Journal of Computational and Applied Mathematics》2008
Many mathematical programming models arising in practice present a block structure in their constraint systems. Consequently, the feasibility of these problems depends on whether the intersection of the solution sets of each of those blocks is empty or not. The existence theorems allow to decide when the intersection of non-empty sets in the Euclidean space, which are the solution sets of systems of (possibly infinite) inequalities, is empty or not. In those situations where the data (i.e., the constraints) can be affected by some kind of perturbations, the problem consists of determining whether the relative position of the sets is preserved by sufficiently small perturbations or not. This paper focuses on the stability of the non-empty (empty) intersection of the solutions of some given systems, which can be seen as the images of set-valued mappings. We give sufficient conditions for the stability, and necessary ones as well; in particular we consider (semi-infinite) convex systems and also linear systems. In this last case we discuss the distance to ill-posedness. 相似文献
1000.
Djurdjica Taka?i Arpad Taka?i Mirjana Štrboja 《Nonlinear Analysis: Theory, Methods & Applications》2010,72(5):2367-313
The nonhomogeneous time-fractional diffusion equation is analyzed in the frames of the Mikusiński calculus. The exact and the approximate solution of the considered problem are constructed and their character is analyzed. 相似文献