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101.
We study sharp minima for multiobjective optimization problems. In terms of the Mordukhovich coderivative and the normal cone, we present sufficient and or necessary conditions for existence of such sharp minima, some of which are new even in the single objective setting.This research was supported by a Central Research Grant of The Hong Kong Polytechnic University (Grant No. G-T 507). Research of the first author was also supported by the National Natural Science Foundation of PR China (Grant No. 10361008) and the Natural Science Foundation of Yunnan Province, China (Grant No. 2003A002M). 相似文献
102.
We prove the dispersionless Hirota equations for the dispersionless Toda, dispersionless coupled modified KP and dispersionless KP hierarchies using an idea from classical complex analysis. We also prove that the Hirota equations characterize the tau functions for each of these hierarchies. As a result, we establish the links between the hierarchies. 相似文献
103.
Some Remarks on the Minty Vector Variational Inequality 总被引:4,自引:0,他引:4
Yang X. M. Yang X. Q. Teo K. L. 《Journal of Optimization Theory and Applications》2004,121(1):193-201
In this paper, we establish some relations between a Minty vector variational inequality and a vector optimization problem under pseudoconvexity or pseudomonotonicity, respectively. Our results generalize those of Ref. 1. 相似文献
104.
An important question in discrete optimization under uncertainty is to understand the persistency of a decision variable, i.e., the probability that it is part of an optimal solution. For instance, in project management,
when the task activity times are random, the challenge is to determine a set of critical activities that will potentially
lie on the longest path. In the spanning tree and shortest path network problems, when the arc lengths are random, the challenge
is to pre-process the network and determine a smaller set of arcs that will most probably be a part of the optimal solution
under different realizations of the arc lengths. Building on a characterization of moment cones for single variate problems,
and its associated semidefinite constraint representation, we develop a limited marginal moment model to compute the persistency
of a decision variable. Under this model, we show that finding the persistency is tractable for zero-one optimization problems
with a polynomial sized representation of the convex hull of the feasible region. Through extensive experiments, we show that
the persistency computed under the limited marginal moment model is often close to the simulated persistency value under various
distributions that satisfy the prescribed marginal moments and are generated independently. 相似文献
105.
This paper deals with the problem of characterizing the pairs of vertices x,y in a connected graph G such that G3 - {x,y} is hamiltonian, where G3 is the cube of G. It is known that the cube G3 is 2-hamiltonian if G is 2-connected. In this paper, we first prove the stronger result that G3 - {x,y} is hamiltonian if either x or y is not a cut-vertex of G, and then proceed to characterize those cut-vertices x and y of G such that G3 -{x,y} is hamiltonian. As a simple consequence of these, we obtain Schaar's characterization of a connected graph G such that G3 is 2-hamiltonian. 相似文献
106.
Summary Monte Carlo simulation of electron scattering in solids is considered and an extremely simplified picture of the process is
demonstrated by a semi-empirical application of the Π theorem of dimensional analysis. The case of electron beam lithography
is presented as an example. A set of parameters fully characterising the process is derived, and their dependence is investigated
on electron energy, substrate thickness and the material physical constants, for a great number of single- and multi-component
substrates. A single generalised argument is shown to be able to effectively describe the properties of forward and backward
scattering of any substrate, in the elastic regime. The physical laws governing the process are approximated through analytical
functions of this argument. These functions are theoretically deduced from very simple models and empirically demonstrated
by fitting the numerical data. The efficacy of the proposed method, applicable to all elemental and composite substrate materials,
is shown in the 5 to 150 keV energy range, with substrate thickness varying from 0.002 to 8 μm. The leading role of diamond
as substrate material, emerging from such an analysis, is finally emphasised. 相似文献
107.
Let D = (V 1, V 2; A) be a directed bipartite graph with |V 1| = |V 2| = n ≥ 2. Suppose that d D (x) + d D (y) ≥ 3n for all x ∈ V 1 and y ∈ V 2. Then, with one exception, D contains two vertex-disjoint directed cycles of lengths 2n 1 and 2n 2, respectively, for any positive integer partition n = n 1 + n 2. This proves a conjecture proposed in [9]. 相似文献
108.
X.X. HUANG K. L. TEO X. Q. YANG 《数学学报(英文版)》2006,22(5):1283-1296
In this paper, an approximate augmented Lagrangian function for nonlinear semidefinite programs is introduced. Some basic properties of the approximate augmented Lagrange function such as monotonicity and convexity are discussed. Necessary and sufficient conditions for approximate strong duality results are derived. Conditions for an approximate exact penalty representation in the framework of augmented Lagrangian are given. Under certain conditions, it is shown that any limit point of a sequence of stationary points of approximate augmented Lagrangian problems is a KKT point of the original semidefinite program and that a sequence of optimal solutions to augmented Lagrangian problems converges to a solution of the original semidefinite program. 相似文献
109.
110.
A. Bencini A. Bianchi M. Micheloni P. Paoletti P. Dapporto P. Paoli E. Garcia-España 《Journal of inclusion phenomena and macrocyclic chemistry》1992,12(1-4):291-304
The interaction of PdCl
4
2–
with the macrocyclic ligands of the series [3k]aneN
k
has been studied both in solution and in the solid state. [18]aneN6 and [21]aneN7 form both mono- and binuclear Pd2+ complexes, whose stability constants have been determined in 0.5 mol dm–3 NaCl at 298.15 K. [21]aneN7 also forms, in solution, a trinuclear species in which an amino group deprotonates to bridge two Pd2+ ions, as observed in the solid state. The crystal structure of the complexes [Pd2([18]aneN6)Cl2][ClO4]2 and [Pd3([21]aneN7)Cl3][ClO4]2 · H2O have been solved by single crystal X-ray analysis. C12H30N6Cl4O8Pd2: monoclinic, space group C2/m,a = 10.876(2),b = 18.117(2),c = 7.043(2) Å, = 113.78(2)°,V = 1270(12) Å3,Z = 2,D
calc = 1.92 g cm-3, = 16.94 cm–1.R = 0.063,R
w = 0.059. C14H36N7CI5O9Pd3: orthorhombic, space groupPcab,a = 13.125(7),b = 13.213(3),c = 33.570(5) Å,V = 5822(3) Å3,Z = 8,D
calc = 2.15 g cm–3, = 21.20 cm–1.R = 0.074,R
w = 0.061. In very acidic solutions the polyammonium cations (H
k
[3k]aneN
k
)
k+
interact with PdCl
4
2–
forming second sphere coordinated species. These reactions have been followed by a microcalorimetric technique in 2 mol dm–3 HCl solutions. The slowness of the reactions of (H10[30]aneN10)10+ with PdCl
4
2–
has been interpreted in terms of inclusion of the anion into the receptor's cavity as shown by the crystal structure of [(PdCl4)(H10[30]aneN10)][PdCl4]2Cl4: triclinic, space group PT,a = 7.760(3),b = 11.448(4),c = 13.399(11) Å, = 96.31(8)°, = 104.50(6)°, = 92.30(3)°,Z = 1.R = 0.046 andR
w = 0.039.This paper is dedicated to the memory of the late Dr C. J. Pedersen. 相似文献