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The surfaces and refractive index of crystalline lens play an important role in the optical performance of human eye.On the basis of two eye models,which are widely applied at present,the effect of lens surfaces and its refractive index distribution on optical imaging is analyzed with the optical design software ZEMAX (Zemax Development Co.,San Diego,USA).The result shows that good image quality can be provided by the aspheric lens surfaces or (and) the gradient-index (GRIN) distribution.It has great potential in the design of intraocular lens (IOL).The eye models with an intraocular implantation are presented. 相似文献
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Lucian Coroianu 《Numerical Functional Analysis & Optimization》2013,34(7):713-727
In this article, we investigate the local approximation and shape preserving properties in subintervals for the Meyer-König and Zeller max-product operators. The results obtained put in evidence that in the class of strictly positive continuous functions, the local properties of the nonlinear Meyer-König and Zeller max-product operators are much stronger and more general than those in the case of their linear counterparts. 相似文献
116.
Zh.G. Nikoghosyan 《Discrete Mathematics》2009,309(8):1925-1930
Bondy conjectured a common generalization of various results in hamiltonian graph theory concerning Hamilton and dominating cycles by introducing a notion of PDλ-cycles (cycles that dominate all paths of lengths at least λ). We show that the minimum degree version of Bondy’s conjecture is true (along with the reverse version) if PDλ-cycles are replaced by CDλ-cycles (cycles that dominate all cycles of lengths at least λ). Fraisse proved a minimum degree generalization including a theorem of Nash-Williams for Hamilton cycles as a special case. We present the reverse version of this result including a theorem of Voss and Zuluaga as a special case. Two earlier less known results (due to the author) are crucial for the proofs of these results. All results are sharp in all respects. A number of possible similar generalizations are conjectured as well. 相似文献
117.
Guy Wolfovitz 《Random Structures and Algorithms》2012,40(2):254-267
Let H = (V,E) be a k ‐uniform hypergraph with a vertex set V and an edge set E. Let V p be constructed by taking every vertex in V independently with probability p. Let X be the number of edges in E that are contained in V p. We give a condition that guarantees the concentration of X within a small interval around its mean. The applicability of this result is demonstrated by deriving new sub‐Gaussian tail bounds for the number of copies of small complete and complete bipartite graphs in the binomial random graph. © 2011 Wiley Periodicals, Inc. Random Struct. Alg., 2012 相似文献
118.
The discretization counterpart of the Cw local flow-box theorem, a Cw normal form result for one-step discretizations of ordinary differential equations in the vicinity of nonequilibria is presented. The very same problem in the less smoother function class ck, k∞ has been investigated in [lo]. The remaining analytic case requires completely different techniques. The proof is based on the parametrized version of a Nash-Moser type implicit function theorem by Belitskii and Tkachenko [5,6]. Connections to results on structural stability under discrctization and backward error analysis are also investigated. 相似文献
119.
For two square matrices that commute, we present some additive results for the Drazin inverse. We also give the application to relative perturbation of eigenvalues when the perturbed matrix commutes with the original matrix and perturbation bounds of the Drazin inverse. 相似文献
120.
《Optimization》2012,61(12):1421-1440
Over the past decades various solution concepts for vector optimization problems have been established and used: among them are efficient, weakly efficient and properly efficient solutions. In contrast to the classical approach, we define a solution to be a set of efficient solutions on which the infimum of the objective function with respect to an appropriate complete lattice (the space of self-infimal sets) is attained. The set of weakly efficient solutions is not considered to be a solution, but weak efficiency is essential in the construction of the complete lattice. In this way, two classic concepts are involved in a common approach. Several different notions of semicontinuity are compared. Using the space of self-infimal sets, we can show that various originally different concepts coincide. A Weierstrass existence result is proved for our solution concept. A slight relaxation of the solution concept yields a relationship to properly efficient solutions. 相似文献