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991.
992.
Custom-produced fluorescent particles are presented and their use as tracers for particle image velocimetry is evaluated.
The fabrication procedure is explained and the main properties of the particles are described. The advantages of using fluorescent
particles over nonfluorescent ones are discussed, in particular, for applications involving large facilities, as those used
in hydraulic research. Images using the produced particles are also shown.
This work was done under the Grants N00014-05-1-0083, N00014-01-1-0540 and
N00014-06-1-0661 from the U.S. Office of Naval Research. 相似文献
993.
José Francisco Rodrigues Manel Sanchón José Miguel Urbano 《Monatshefte für Mathematik》2008,17(1):303-322
The aim of this paper is twofold: to prove, for L
1-data, the existence and uniqueness of an entropy solution to the obstacle problem for nonlinear elliptic equations with variable
growth, and to show some convergence and stability properties of the corresponding coincidence set. The latter follow from
extending the Lewy-Stampacchia inequalities to the general framework of L
1. 相似文献
994.
Antonio Alarcó n Leonor Ferrer Francisco Martí n 《Transactions of the American Mathematical Society》2007,359(6):2819-2829
The singly periodic genus-one helicoid was in the origin of the discovery of the first example of a complete minimal surface with finite topology but infinite total curvature, the celebrated Hoffman-Karcher-Wei's genus one helicoid. The objective of this paper is to give a uniqueness theorem for the singly periodic genus-one helicoid provided the existence of one symmetry.
995.
Blanca Climent-Ezquerra Francisco Guillén-González Marko Rojas-Medar 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2006,51(10):984-998
In this paper we prove existence of weak solution with the reproductivity in time property, for a penalized PDE’s system related
to a nematic liquid crystal model.
This problem is relatively explict when time-independent Dirichlet boundary conditions are imposed for the orientation of
crystal molecules. Nevertheless, for the time-dependent case, the treatment of the problem is completely different. The verification
of a maximum principle for weak reproductive solutions is fundamental in the argument. 相似文献
996.
Let 1<α≦β<∞ andF be an arbitrary closed subset of the interval [α,β]. An Orlicz sequence spacel
φ (resp. an Orlicz function spaceL
φ(μ)) with associated indices α and β is found in such a way that the set of valuesp for which thel
p-space is isomorphic to a complemented subspace ofl
φ (resp.L
φ(μ)) is precisely the given setF (resp.F ∪ {2}). Also, a recent result of Hernández and Peirats [1] is extended showing that, even for the case in which the indices
satisfy αφ
∞<2<βφ
∞, there exist minimal Orlicz function spacesL
φ(μ) with no complemented copy ofl
p for anyp ≠ 2.
Supported in part by CAICYT grant 0338-84. 相似文献
997.
This paper presents a new methodology whereby the relationships among points of interest appearing in Internet Web pages may
be graphically represented. This is done by quantifying the various points and representing them graphically using an intuitive
interpretation of the similarity of sets. The similarity or interrelationships existing among various lines of research may
be studied based on information taken from the Web pages using function taken from Learning Theory.
A visual analysis of those interrelationships has been applied to the field of machine learning during the time interval May
2003–May 2004. 相似文献
998.
We consider matching markets at a senior level, where workers are assigned to firms at an unstable matching—the status-quo—which might not be Pareto efficient. It might also be that none of the matchings Pareto superior to the status-quo are Core stable. We propose two weakenings of Core stability: status-quo stability and weakened stability, and the respective mechanisms which lead any status-quo to matchings meeting the stability requirements above mentioned. The first one is inspired by the Top trading cycle and Deferred Acceptance procedures, the other one belongs to the family of Branch and Bound algorithms. The last procedure finds a core stable matching in many-to-one markets whenever it exists, dispensing with the assumption of substitutability. 相似文献
999.
Francisco Javier Zaragoza Martínez 《Discrete Mathematics》2008,308(8):1366-1374
The windy postman problem is the NP-hard problem of finding the minimum cost of a tour traversing all edges of an undirected graph, where the cost of an edge depends on the direction of traversal. Given an undirected graph G, we consider the polyhedron O(G) induced by a linear programming relaxation of the windy postman problem. We say that G is windy postman perfect if O(G) is integral. There exists a polynomial-time algorithm, based on the ellipsoid method, to solve the windy postman problem for the class of windy postman perfect graphs. By considering a family of polyhedra related to O(G), we prove that series-parallel graphs are windy postman perfect, therefore solving a conjecture of Win. 相似文献
1000.
The baroclinic stability of a family of two time‐level, semi‐implicit schemes for the 3D hydrostatic, Boussinesq Navier–Stokes equations (i.e. the shallow water equations), which originate from the TRIM model of Casulli and Cheng (Int. J. Numer. Methods Fluids 1992; 15 :629–648), is examined in a simple 2D horizontal–vertical domain. It is demonstrated that existing mass‐conservative low‐dissipation semi‐implicit methods, which are unconditionally stable in the inviscid limit for barotropic flows, are unstable in the same limit for baroclinic flows. Such methods can be made baroclinically stable when the integrated continuity equation is discretized with a barotropically dissipative backwards Euler scheme. A general family of two‐step predictor‐corrector schemes is proposed that have better theoretical characteristics than existing single‐step schemes. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献