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101.
The classification of hyperspectral images with a few labeled samples is a major challenge which is difficult to meet unless some spatial characteristics can be exploited. In this study, we proposed a novel spectral-spatial hyperspectral image classification method that exploited spatial autocorrelation of hyperspectral images. First, image segmentation is performed on the hyperspectral image to assign each pixel to a homogeneous region. Second, the visible and infrared bands of hyperspectral image are partitioned into multiple subsets of adjacent bands, and each subset is merged into one band. Recursive edge-preserving filtering is performed on each merged band which utilizes the spectral information of neighborhood pixels. Third, the resulting spectral and spatial feature band set is classified using the SVM classifier. Finally, bilateral filtering is performed to remove “salt-and-pepper” noise in the classification result. To preserve the spatial structure of hyperspectral image, edge-preserving filtering is applied independently before and after the classification process. Experimental results on different hyperspectral images prove that the proposed spectral-spatial classification approach is robust and offers more classification accuracy than state-of-the-art methods when the number of labeled samples is small. 相似文献
102.
103.
We state and prove characterization theorem for semi-classical orthogonal polynomials on nonuniform lattices (quadratic lattices of a discrete or q-discrete variable). This theorem proves the equivalence between the four characterization properties, namely, the Pearson type equation for the linear functional, the strictly quasi-orthogonality of the derivatives, the structure relation, and the Riccati equation for the formal Stieltjes function. We give the classification of the semi-classical linear functional of class one on nonuniform lattice. Using the definition and the properties of the associated orthogonal polynomials, we prove that semi-classical orthogonal polynomials satisfy the second-order divided difference equation on nonuniform lattices. 相似文献
104.
105.
In this paper the distribution of the zeros of the error function for bestL
1-approximation by rational functions fromR
n,m
is considered. It is shown that the maximal distance between such zeros isO(1/(n–m)), ifn > m.Communicated by Edward B. Saff. 相似文献
106.
XIANG DaoHong 《中国科学 数学(英文版)》2011,(1)
We continue our study on classification learning algorithms generated by Tikhonov regularization schemes associated with Gaussian kernels and general convex loss functions. Our main purpose of this paper is to improve error bounds by presenting a new comparison theorem associated with general convex loss functions and Tsybakov noise conditions. Some concrete examples are provided to illustrate the improved learning rates which demonstrate the effect of various loss functions for learning algorithms. In our ... 相似文献
107.
YanminWang EricForssberg JingxianLi ZhidongPan 《中国颗粒学报》2003,1(2):70-75
This paper describes the use of a disc-stack nozzle centrifuge for wet classification of ultra-fine particles of calcium carbonate. The influences of G-force and disc geometry on the performance of the ultra-fine classification have been investigated. The results have demonstrated that the efficiency of the classification can be increased by (1) applying a relatively moderate G-force and (2) the use of stud spacer discs in the centrifuge. The increased extraction of the fine particles is related to the formation of the appropriate fluid velocity profile at a lower G-force and a circumferential motion without meridional barriers for the case of the stud spacer discs. 相似文献
108.
Andrés Perea y Monsuwé Mathijs Jansen Dries Vermeulen 《International Journal of Game Theory》2000,29(3):433-450
By a player splitting we mean a mechanism that distributes the information sets of a player among so-called agents. A player
splitting is called independent if each path in the game tree contains at most one agent of every player. Following Mertens
(1989), a solution is said to have the player splitting property if, roughly speaking, the solution of an extensive form game
does not change by applying independent player splittings. We show that Nash equilibria, perfect equilibria, Kohlberg-Mertens
stable sets and Mertens stable sets have the player splitting property. An example is given to show that the proper equilibrium
concept does not satisfy the player splitting property. Next, we give a definition of invariance under (general) player splittings
which is an extension of the player splitting property to the situation where we also allow for dependent player splittings.
We come to the conclusion that, for any given dependent player splitting, each of the above solutions is not invariant under
this player splitting. The results are used to give several characterizations of the class of independent player splittings
and the class of single appearance structures by means of invariance of solution concepts under player splittings.
Received: December 1996/Revised Version: January 2000 相似文献
109.
Licun Xue 《International Journal of Game Theory》2000,29(3):339-357
This paper defines “negotiation-proof Nash equilibrium', a notion that applies to environments where players can negotiate
openly and directly prior to the play of a noncooperative game. It recognizes the possibility that a group of self-interested
players may choose, voluntarily and without binding agreement, to coordinate their choice of strategies and make joint objections;
moreover, it takes the perfect foresight of rational players fully into account. The merit of the notion of negotiation-proof
Nash equilibrium is twofold: (1) It offers a way to rectify the nestedness assumption and myopia embedded in the notion of
coalition-proof Nash equilibrium. (2) The negotiation process is formalized by a “graph”, which serves as a natural extension to the approach that models
preplay communication by an extensive game.
Received: October 1998/Final version: May 2000 相似文献
110.
We prove a direct theorem for shape preservingL
p
-approximation, 0p, in terms of the classical modulus of smoothnessw
2(f, t
p
1
). This theorem may be regarded as an extension toL
p
of the well-known pointwise estimates of the Timan type and their shape-preserving variants of R. DeVore, D. Leviatan, and X. M. Yu. It leads to a characterization of monotone and convex functions in Lipschitz classes (and more general Besov spaces) in terms of their approximation by algebraic polynomials.Communicated by Ron DeVore. 相似文献