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101.
GaAs:Cr探测器中子辐照改性研究 总被引:3,自引:0,他引:3
介绍了一种新型脉冲辐射探测器以及提高其性能的一种方法,并报告了探测器性能与中子积分通量关系的实验结果。 相似文献
102.
研究了偶氮基染料掺杂薄膜MO-PVA和EO-PVA的双光子存储特性。在对薄膜用Ar^+激光作预激发下实现了He-Ne激光的红光存储。获得了实时和短时存储照片。光电记录存储曲线,分析了双光四能级系统的存储机制。实现确定了最佳预激发功率约为0.28W/cm^2,最小He-Ne光可存储功率密度低于0.2W/cm^2。 相似文献
103.
Matvei Libine 《Topology》2008,47(1):1-39
The Berline-Vergne integral localization formula for equivariantly closed forms ([N. Berline, M. Vergne, Classes caractéristiques équivariantes. Formules de localisation en cohomologie équivariante, C. R. Acad. Sci. Paris 295 (1982) 539-541], Theorem 7.11 in [N. Berline, E. Getzler, M. Vergne, Heat Kernels and Dirac Operators, Springer-Verlag, 1992]) is well-known and requires the acting Lie group to be compact. In this article, we extend this result to real reductive Lie groups GR.As an application of this generalization, we prove an analogue of the Gauss-Bonnet theorem for constructible sheaves. If F is a GR-equivariant sheaf on a complex projective manifold M, then the Euler characteristic of M with respect to F
104.
János Folláth 《Periodica Mathematica Hungarica》2008,57(1):73-81
In a series of papers Mauduit and Sárközy (partly with coauthors) studied finite pseudorandom binary sequences and they constructed sequences with strong pseudorandom properties. In these constructions fields with prime order were used. In this paper a new construction is presented, which is based on finite fields of order 2 k . 相似文献
105.
Nicholas J. Cavenagh Catherine Greenhill Ian M. Wanless 《Random Structures and Algorithms》2008,33(3):286-309
Let L be chosen uniformly at random from among the latin squares of order n ≥ 4 and let r,s be arbitrary distinct rows of L. We study the distribution of σr,s, the permutation of the symbols of L which maps r to s. We show that for any constant c > 0, the following events hold with probability 1 ‐ o(1) as n → ∞: (i) σr,s has more than (log n)1?c cycles, (ii) σr,s has fewer than 9 cycles, (iii) L has fewer than n5/2 intercalates (latin subsquares of order 2). We also show that the probability that σr,s is an even permutation lies in an interval and the probability that it has a single cycle lies in [2n‐2,2n‐2/3]. Indeed, we show that almost all derangements have similar probability (within a factor of n3/2) of occurring as σr,s as they do if chosen uniformly at random from among all derangements of {1,2,…,n}. We conjecture that σr,s shares the asymptotic distribution of a random derangement. Finally, we give computational data on the cycle structure of latin squares of orders n ≤ 11. © 2008 Wiley Periodicals, Inc. Random Struct. Alg., 2008 相似文献
106.
Zhefeng Xu 《Proceedings of the American Mathematical Society》2008,136(12):4175-4184
We obtain an asymptotic formula for the -th power mean of odd primitive character sums over the interval .
107.
108.
Let E/F be a Galois extension of number fields with Galois group G=Gal(E/F), and let p be a prime not dividing #G. In this paper, using character theory of finite groups, we obtain the upper bound of #K2OE if the group K2OE is cyclic, and prove some results on the divisibility of the p-rank of the tame kernel K2OE, where E/F is not necessarily abelian. In particular, in the case of G=Cn, Dn, A4, we easily get some results on the divisibility of the p-rank of the tame kernel K2OE by the character table. Let E/Q be a normal extension with Galois group Dl, where l is an odd prime, and F/Q a non-normal subextension with degree l. As an application, we show that f|p-rank K2OF, where f is the smallest positive integer such that pf≡±1(mod l). 相似文献
109.
利用特征和与指数和的估计,研究了一些同余问题的例外集合.具体来说,设p为充分大的素数,集合Y■Zp,正整数N相似文献
110.
The main purpose of this paper is using the analytic method and the properties of trigonometric sums and character sums to study the computational problem of one kind hybrid power mean involving two-term exponential sums and polynomial character sums. Then the authors give some interesting calculating formulae for them. 相似文献