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151.
A. G. D’yakonov 《Computational Mathematics and Mathematical Physics》2008,48(5):866-876
It is shown that, in the pattern recognition problem with two nonoverlapping classes, the matrices of estimates of the object closeness are described by a metric. The transition to the algebraic closure of the model of recognizing operators of finite degree corresponds to the application of a special transformation of this metric. It is proved that the minimal degree correct algorithm can be found as a polynomial of a special form. A simple criterion for testing classification implementations is obtained. 相似文献
152.
Ivan Cheltsov 《Advances in Mathematics》2008,217(1):97-124
We study global log canonical thresholds of anticanonically embedded quasismooth weighted Fano threefold hypersurfaces having terminal quotient singularities to prove the existence of a Kähler-Einstein metric on most of them, and to produce examples of Fano varieties with infinite discrete groups of birational automorphisms. 相似文献
153.
Henry P. Stapp 《Foundations of Physics Letters》1989,2(1):9-13
Kraus claims that the argument for action at a distance depends upon the classical prejudice that a measurement always measures something that already exists. It is shown that in the example considered by Kraus no assumption about pre-existing results is needed. A criterion proposed by Kraus for a theory to be compatible with locality is shown to be untenable. 相似文献
154.
J. A. H. Coaquira H. R. Rechenberg C. Marquina M. R. Ibarra A. M. Benito W. Maser E. Muñoz M. T. Martínez 《Hyperfine Interactions》2001,134(1):103-108
Iron particles encaged in carbon nanocapsules have been produced by the Krätschmer–Huffmann carbon-arc discharge method. Soot, collarette and cathode samples have been characterized by Mössbauer spectroscopy and magnetic measurements in the temperature range 4.2–300 K. Different iron phases and iron-carbon solid solutions have been detected in our samples. The Einstein model has been used to evaluate the coupling constant between the particles and their environment, yielding values of the order 1–10 N/m. Irreversibilities observed at ZFC and FC curves for soot samples would suggest the presence of superparamagnetism only if the particles presented a blocking temperature above 300 K. 相似文献
155.
Weiping Yin 《Journal of Mathematical Analysis and Applications》2008,339(1):295-302
Monge-Ampère equation is a nonlinear equation with high degree, therefore its numerical solution is very important and very difficult. In present paper the numerical method of Dirichlet's problem of Monge-Ampère equation on Cartan-Hartogs domain of the third type is discussed by using the analytic method. Firstly, the Monge-Ampère equation is reduced to the nonlinear ordinary differential equation, then the numerical method of the Dirichlet problem of Monge-Ampère equation becomes the numerical method of two point boundary value problem of the nonlinear ordinary differential equation. Secondly, the solution of the Dirichlet problem is given in explicit formula under the special case, which can be used to check the numerical solution of the Dirichlet problem. 相似文献
156.
157.
非紧超凸度量空间中的一个新的极大元定理及其对抽象经济的应用 总被引:2,自引:0,他引:2
在非紧超凸度量空间中建立了一个新的极大元定理.作为应用,获得了连续选择及其不动点定理和一个Browder-Fan不动点定理.最后,新建了非紧超凸度量空间中的定性对策和抽象经济的平衡点存在定理. 相似文献
158.
Isotropic Berwald metrics are as a generalization of Berwald metrics. Shen proved that every Berwald metric is of vanishing S-curvature. In this paper, we generalize this fact and prove that every isotropic Berwald metric is of isotropic S-curvature. Let F = α + β be a Randers metric of isotropic Berwald curvature. Then it corresponds to a conformal vector field through navigation representation. 相似文献
159.
In this paper some properties of a symmetric tensor field T(X, Y) = g(A(X), Y) on a Riemannian manifold (M,g) without boundary which satisfies the quasi-Einstein equation Rij-S/2gij=Tij+bξiξj are given. The necessary and sufficient conditions for this tensor to satisfy the quasi-Einstein equation are also obtained. 相似文献
160.
Paul Halpern 《Physics in Perspective (PIP)》2005,7(4):390-403
I explore the early life and contributions of Peter Bergmann (1915–2002), focusing on his family background, education, and
ideas. I examine how Bergmann’s formative years were shaped by the outspoken influence of his mother, a leading educational
reformer; the distinguished reputation of his father, a renowned materials chemist; and his cherished hope of working with
Albert Einstein (1879–1955), to whom he eventually became an assistant. Inspired by these and other notable thinkers, Bergmann
became an exemplary organizer, educator, and mentor in the fields of general relativity and quantum gravity. 相似文献