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991.
Consider the perturbed harmonic oscillator Ty = -y" + x2y + q(x)y on L2(R) where the real potential q satisfy some assumption on infinity (the case q L2(R), (t+1)-rdt), r < 1 is covered). 相似文献
992.
Jean-Fran?ois?Cordeau Gilbert?LaporteEmail author 《4OR: A Quarterly Journal of Operations Research》2003,1(2):89-101
The Dial-a-Ride Problem (DARP) consists of designing vehicle routes and schedules for n users who specify pick-up and drop-off requests between origins and destinations. The aim is to plan a set of m minimum cost vehicle routes capable of accommodating as many users as possible, under a set of constraints. The most common example arises in door-to-door transportation for elderly or disabled people. The purpose of this article is to review the scientific literature on the DARP. The main features of the problem are described and classified and some modeling issues are discussed. A summary of the most important algorithms is provided.AMS classification:
90B06, 90C27, 90C59 相似文献
993.
Adam?N.?LetchfordEmail author Andrea?Lodi 《4OR: A Quarterly Journal of Operations Research》2003,1(3):209-224
Given an integer polyhedron
, an integer point
, and a point
, the primal separation problem is the problem of finding a linear inequality which is valid for P
I
, violated by x
*, and satisfied at equality by
. The primal separation problem plays a key role in the primal approach to integer programming. In this paper we examine the complexity of primal separation for several well-known classes of inequalities for various important combinatorial optimization problems, including the knapsack, stable set and travelling salesman problems.Received: November 2002, Revised: March 2003, 相似文献
994.
We derive an elementary formula for Janossy densities for determinantal point processes with a finite rank projection-type kernel. In particular, for =2 polynomial ensembles of random matrices we show that the Janossy densities on an interval I can be expressed in terms of the Christoffel–Darboux kernel for the orthogonal polynomials on the complement of I. 相似文献
995.
Sylvia Pulmannová 《International Journal of Theoretical Physics》2003,42(7):1413-1423
A noncommutative version of generalized Sasaki projections in pseudoeffect algebras is introduced. It is proved that an ideal in a pseudoeffect algebra is Riesz if and only if it is closed under the right and left Sasaki projections. In lattice ordered pseudoeffect algebras, it is shown that generalized Sasaki projections are one-element sets, and their explicit form is found. It is shown that if a supremum of a normal Riesz ideal in a lattice ordered pseudoeffect algebra exists, it is a central element. These results extend those obtained recently by Avallone and Vitolo for effect algebras. 相似文献
996.
In this paper strongly nonlinear oscillator equations will be studied.It will be shown that the recently developed perturbation method based onintegrating factors can be used to approximate first integrals. Not onlyapproximations of first integrals will be given, butit will also be shown how in a rather efficient way the existence and stability oftime-periodic solutions can be obtained from these approximations. In particularthe generalized Rayleigh oscillator equation
will be studied in detail, and it will beshown that at least five limit cycles can occur. 相似文献
997.
In this paper, we continue extending the theory of boundary-value problems to ordinary differential equations and inclusions with discontinuous right-hand side. To this end, we construct a new version of the method of shifts along trajectories. We compare the results obtained by the new approach and those obtained by the method of Fuik spectra. 相似文献
998.
Suppose that k and l are integers such that
and
, M
k is a set of numbers without kth powers, and
. In this paper, we obtain asymptotic estimates of the sums
over
相似文献
999.
Norimichi Hirano 《Journal of Mathematical Analysis and Applications》2003,278(1):83-92
Let N?2 and be a bounded domain. In the present paper, we show the existence of infinity many solutions of nonlinear Dirichlet boundary value problem
1000.
Yuri Kozitsky Piotr Oleszczuk 《Journal of Mathematical Analysis and Applications》2003,277(2):423-437
Differential operators ?(Δθ,ω), where ? is an exponential type entire function of a single complex variable and Δθ,ω=(θ+ωz)D+zD2, D=∂/∂z, , θ?0, , acting in the spaces of exponential type entire function are studied. It is shown that, for ω?0, such operators preserve the set of Laguerre entire functions provided the function ? also belongs to this set. The latter consists of the polynomials possessing real nonpositive zeros only and of their uniform limits on compact subsets of the complex plane . The operator exp(aΔθ,ω), a?0 is studied in more details. In particular, it is shown that it preserves the set of Laguerre entire functions for all . An integral representation of exp(aΔθ,ω), a>0 is obtained. These results are used to obtain the solutions to certain Cauchy problems employing Δθ,ω. 相似文献