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51.
We have investigated the feasibility of observing an ultra-low-Q-value beta-decay branch of 135Cs by applying the microscopic quasiparticle-phonon model with a realistic two-body nuclear interaction. This work was motivated by an earlier combined experimental and theoretical work on decays of 115In. The inaccuracy of the ground-state-to-ground-state Q value limits our ability to draw definite conclusions, and therefore modern precision measurements for it are called for. We present the computed partial half-lives of each channel for the most likely ranges of Q values. 相似文献
52.
以天然黄铁矿为样本,用Cary 500型紫外可见近红外分光光度计在200~2 000 nm范围内测出了样品的吸收谱和反射谱,计算出了吸收系数,并根据Tauc规则算出了样品的禁带宽度.结果表明:所测天然黄铁矿光吸收系数在105数量级;在吸收图谱中出现了明显的肩行结构,可以判断样品属于间接禁带半导体,其禁带宽度为0.64 ... 相似文献
53.
《Annals of Pure and Applied Logic》2014,165(2):520-551
In this paper, we introduce systems of nonstandard second-order arithmetic which are conservative extensions of systems of second-order arithmetic. Within these systems, we do reverse mathematics for nonstandard analysis, and we can import techniques of nonstandard analysis into analysis in weak systems of second-order arithmetic. Then, we apply nonstandard techniques to a version of Riemannʼs mapping theorem, and show several different versions of Riemannʼs mapping theorem. 相似文献
54.
J.A. Tenreiro Machado 《Optimization》2014,63(8):1167-1179
55.
56.
Stefano Berardi 《Mathematical Logic Quarterly》2004,50(1):41-46
A basic result in intuitionism is Π02‐conservativity. Take any proof p in classical arithmetic of some Π02‐statement (some arithmetical statement ?x.?y.P(x, y), with P decidable). Then we may effectively turn p in some intuitionistic proof of the same statement. In a previous paper [1], we generalized this result: any classical proof p of an arithmetical statement ?x.?y.P(x, y), with P of degree k, may be effectively turned into some proof of the same statement, using Excluded Middle only over degree k formulas. When k = 0, we get the original conservativity result as particular case. This result was a by‐product of a semantical construction. J. Avigad of Carnegie Mellon University, found a short, direct syntactical derivation of the same result, using H. Friedman's A‐translation. His proof is included here with his permission. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
57.
Eric S. Egge 《Discrete Mathematics》2006,306(6):552-563
Gire, West, and Kremer have found ten classes of restricted permutations counted by the large Schröder numbers, no two of which are trivially Wilf-equivalent. In this paper we enumerate eleven classes of restricted signed permutations counted by the large Schröder numbers, no two of which are trivially Wilf-equivalent. We obtain five of these enumerations by elementary methods, five by displaying isomorphisms with the classical Schröder generating tree, and one by giving an isomorphism with a new Schröder generating tree. When combined with a result of Egge and a computer search, this completes the classification of restricted signed permutations counted by the large Schröder numbers in which the set of restrictions consists of two patterns of length 2 and two of length 3. 相似文献
58.
AnInequalityofMatrixandBayesUnbiasedEstimatesZhangYaoting(ShanghaiUniversityofFinanceandEconomics,200433)AbstractTheinequali... 相似文献
59.
A computational test is proposed for existence of solution in nonlinear systems. In this test, an interval inclusion of Newton mapping is estimated applying affine arithmetic. Numerical examples are presented to show the efficiency of this test. 相似文献
60.
Charles Audet Pierre Hansen Frédéric Messine 《Journal of Combinatorial Theory, Series A》2007,114(1):135-150
The convex octagon with unit diameter and maximum perimeter is determined. This answers an open question dating from 1922. The proof uses geometric reasoning and an interval arithmetic based global optimization algorithm to solve a series of non-linear and non-convex programs involving trigonometric functions. 相似文献