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991.
Ricard Martí 《Journal of Combinatorial Theory, Series A》2008,115(4):547-568
Let k=Fq be a finite field. We enumerate k-rational n-sets of (unordered) points in a projective space PN over k, and we compute the generating function for the numbers of PGLN+1(k)-orbits of these n-sets. For N=1,2 we obtain a formula for these numbers of orbits as a polynomial in q with integer coefficients. 相似文献
992.
Xianglei Kong 《中国光学快报(英文版)》2008,6(6)
Direct mass spectrometric analysis of complex biological samples is very important and challenging. In this paper, nanodiamonds have been successfully used in matrix-assisted laser desorption/ionization mass spectrometric analysis of human serum and urine. As a practical tool and platform, it can be widely used in the field of humoral proteomics, and it plays a very promising role in clinical diagnosis, including identification of novel disease-associated biomarkers. 相似文献
993.
M. V. Komarova I. S. Kremnev M. Yu. Nalimov 《Theoretical and Mathematical Physics》2009,158(2):167-178
We find the family of instantons of the Kraichnan model with a frozen velocity field. Using these instantons, we investigate
the asymptotic behavior of higher orders of the perturbation theory series constructed for the response function. We demonstrate
that although the number of diagrams increases factorially with the degree of the perturbation series term, the perturbation
series itself has a finite and sometimes even infinite convergence radius. We thus disprove the commonly accepted view that
the type of series convergence can be determined by estimating the number of diagrams in higher orders of the perturbation
theory.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 158, No. 2, pp. 200–213, February, 2009. 相似文献
994.
In this article, we introduce the concept of skewness to the Gaussian random field theory by defining a new two-dimensional non-Gaussian random field called skew-Gaussian random field. We derive the expected Euler characteristic of its excursion set. Moreover, an approximation to the size distribution of one connected component is derived. As an illustration, we present a simulation study to compare the approximation mechanism with the exact one. 相似文献
995.
Let K be an imaginary quadratic field with class number one and ? be a rational prime that splits in K. We prove that mod ?, a system of Hecke eigenvalues occurring in the first cohomology group of some congruence subgroup Γ of SL2(OK) can be realized, up to twist, in the first cohomology with trivial coefficients after increasing the level of Γ by (?). 相似文献
996.
YCESAN Ahmet~ KEN A.Ceylan Department of Mathematics Süleyman Demirel University Isparta Turkey 《中国科学A辑(英文版)》2008,51(2):233-240
We derive intrinsic formulation for elastic line deformed on a pseudo-hypersurface by an external field in the pseudo-Euclidean spaces E_v~n.This formulation determines elastic line deformed on a pseudo-hypersurface. 相似文献
997.
A scheme for creating an arbitrary coherent superposition of two atomic states in serial multi-A-type system is proposed.This technique with the application of a control field is based on the existence of two degenerate dark states and their interaction.The mixing of the dark states can be controlled by changing the relative delay time of the control pulse.One can get any desired superposition by changing the delay time of the control pulse. 相似文献
998.
M. L. Filshtinsky D. I. Bardzokas 《Archive of Applied Mechanics (Ingenieur Archiv)》2001,71(4-5):341-352
Summary The antiplane steady dynamic problem of the theory of elasticity for an isotropic layer and a half-layer weakened by tunnel
cavities of arbitrary cross section is investigated. A radiating monochromatic shear wave (SH-wave) is considered as loading. Using the constructed Green's functions for a layer and a half- layer, the corresponding
boundary problems are reduced to the Fredholm's integral equations of the second kind. The obtained algorithm is realized
numerically by the quadrature method. Results specifying the influence of the openings configuration, their number and relative
position, types of edge conditions and inertia effects on tangential stress concentration are given.
Received 13 July 1999; accepted for publication 20 July 2000 相似文献
999.
In this paper, the question posed in the title is critically examined on the basis of the available literature evidence implying the positive answer. The distinction between, on the one hand, the actual crystal field (CF) or equivalently ligand field (LF) related quantities and, on the other hand, the actual zero-field splitting (ZFS) or equivalently fine structure (FS) quantities, is elucidated. The origin and possible roots of the incorrect terminology consisting in mixing up the two physically distinct quantities at different levels are examined. Aspects concerning Hamiltonians, parameters, energy level splitting, and nature of the operators involved are taken into account. Problems with the various notations for the operators and parameters used in the electron magnetic resonance (EMR) area are also identified and reviewed. A large number of cases of incorrect terminology and other inconsistencies identified in the course of a comprehensive literature survey are analyzed and systematically classified. Implications of the confusion in question, which go beyond the simple semantic issues, are discussed. The results of the survey reveal that the two most serious categories of this confusion lead to misinterpretation of the experimental EMR data. Several examples of serious misinterpretations found in the books, reviews, and original papers are discussed. The incorrect terminology contributes also to misleading keyword classifications of papers in journals as well as references in scientific literature databases. Thus, the database searches may produce unreliable outcomes. Examples of such outcomes are also shown. It is concluded that, in order to prevent further proliferation of the incorrect terminology and thus to increase reliability of the published EMR data, a concerted effort within the EMR community is indispensable. Various ways in this regard at the international level are suggested. 相似文献
1000.
本文提出直观法的理论 ,举出用直观法构造单参数假设检验拒绝域的应用实例 ,并得出构造形如 ( * )式的检验拒绝域的一种方法 相似文献