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91.
Shiffman proved his famous first theorem, that if A R3 is a compact minimal annulus bounded by two convex Jordan curves in parallel (say horizontal) planes, then A is foliated by strictly convex horizontal Jordan curves. In this article we use Perron's method to construct minimal annuli which have a planar end and are bounded by two convex Jordan curves in horizontal planes, but the horizontal level sets of the surfaces are not all convex Jordan curves or straight lines. These surfaces show that unlike his second and third theorems, Shiffman's first theorem is not generalizable without further qualification. 相似文献
92.
We study the convergence of rational interpolants with prescribed poles on the unit circle to the Herglotz-Riesz transform of a complex measure supported on [–, ]. As a consequence, quadrature formulas arise which integrate exactly certain rational functions. Estimates of the rate of convergence of these quadrature formulas are also included.This research was performed as part of the European project ROLLS under contract CHRX-CT93-0416. 相似文献
93.
Allan J. MacLeod 《Numerical Algorithms》1996,12(2):259-272
Rational approximations to the sine integralSi(x) and cosine-integralCi(x) are developed which give an accuracy of 20sf. The robust construction of software for these functions is discussed, together with a test procedure for assessing the performance of such codes. Use of the tests discovers a major error in the netlib library FN codes forSi. Fortran versions of the codes and tests are available by electronic mail. 相似文献
94.
Consider discrete storage processes that are modulated by environmental processes. Environmental processes cause interruptions in the input and/or output processes of the discrete storage processes. Due to the difficulties encountered in the exact analysis of such discrete storage systems, often Poisson flow and/or fluid flow models with the same modulating environmental processes are proposed as approximations for these systems. The analysis of Poisson flow and fluid flow models is much easier than that of the discrete storage processes. In this paper we give sufficient conditions under which the content of the discrete storage processes can be bounded by the Poisson flow and the fluid flow models. For example, we show that Poisson flow models and the fluid flow models developed by Kosten (and by Anick, Mitra and Sondhi) can be used to bound the performance of infinite (finite) source packetized voice/data communication systems. We also show that a Poisson flow model and the fluid flow model developed by Mitra can be used to bound the buffer content of a two stage automatic transfer line. The potential use of the bounding techniques presented in this paper, of course, transcends well beyond these examples.Supported in part by NSF grant DMS-9308149. 相似文献
95.
The generalized linear complementarity problem revisited 总被引:5,自引:0,他引:5
Given a vertical block matrixA, we consider in this paper the generalized linear complementarity problem VLCP(q, A) introduced by Cottle and Dantzig. We formulate this problem as a linear complementarity problem with a square matrixM, a formulation which is different from a similar formulation given earlier by Lemke. Our formulation helps in extending many
well-known results in linear complementarity to the generalized linear complementarity problem. We also show that the class
of vertical block matrices which Cottle and Dantzig's algorithm can process is the same as the class of equivalent square
matrices which Lemke's algorithm can process. We also present some degree-theoretic results on a vertical block matrix. 相似文献
96.
求解交通均衡配流问题的新算法 总被引:1,自引:0,他引:1
给出了一个求解交通均衡配流问题的新算法,证明了新算法的收敛性,并在小型交通网络上进行了初步的数值试验. 相似文献
97.
In the solution methods of the symmetric cone complementarity problem (SCCP), the squared norm of a complementarity function
serves naturally as a merit function for the problem itself or the equivalent system of equations reformulation. In this paper,
we study the growth behavior of two classes of such merit functions, which are induced by the smooth EP complementarity functions
and the smooth implicit Lagrangian complementarity function, respectively. We show that, for the linear symmetric cone complementarity
problem (SCLCP), both the EP merit functions and the implicit Lagrangian merit function are coercive if the underlying linear
transformation has the P-property; for the general SCCP, the EP merit functions are coercive only if the underlying mapping has the uniform Jordan
P-property, whereas the coerciveness of the implicit Lagrangian merit function requires an additional condition for the mapping,
for example, the Lipschitz continuity or the assumption as in (45).
The authors would like to thank the two anonymous referees for their helpful comments which improved the presentation of this
paper greatly.
The research of J.-S. Chen was partially supported by National Science Council of Taiwan. 相似文献
98.
二阶积分微分方程的广义拟线性化方法 总被引:1,自引:0,他引:1
运用广义拟线性化方法研究了正规锥上的二阶积分微分方程初值问题,获得了逼近解序列一致且平方收敛的结果. 相似文献
99.
In this paper, based on the smooth point of the unit ball and its support linear functional,we show two equivalent formulations of the isometric extension problem between the unit spheres of strictly convex two-dimensional normed spaces. We prove that these equivalent formulations have a positive answer in a special case. 相似文献
100.
This paper, motivated by the need to predict performance of production systems with random arrivals, setup times and revisitation,
presents an imbedded Markov chain analysis of the underlyingM/G/1 queue with two customer classes, changeover times and instantaneous Bernoulli feedback. It is assumed that jobs are scheduled
according to the exhaustive alternative priority queue discipline. Expressions for the mean waiting time and the nonsaturation
condition are derived under two different priority assignments to the repeat customers. Sojourn times under these priority
assignments are shown to possess a convex ordering. Results of the study are also applicable to data communication networks
that operate under cyclic switching mechanisms.
Research supported in part by Natural Sciences and Engineering Research Council of Canada. 相似文献