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41.
我们用三角和的性质研究一类三次Gauss和与两项指数和混合均值的计算问题,并给出一个精确的计算公式. 相似文献
42.
We relate the distribution of the absolute value of some generalized Gauss sums to the absolute irreducibility of some polynomials in two variables in characteristic 0 and p. 相似文献
43.
The main purpose of this paper is using estimates for trigonometric sums and properties of congruence to study the computation of one kind of fourth power mean of a generalized three-term exponential sum, and give an interesting identity for it. 相似文献
44.
Cyclic codes are an important class of linear codes, whose weight distribution have been extensively studied. So far, most of previous results obtained were for cyclic codes with no more than three nonzeros. Recently, the authors of [37] constructed a class of cyclic codes with arbitrary number of nonzeros, and computed the weight distribution for several cases. In this paper, we determine the weight distribution for a new family of such codes. This is achieved by introducing certain new methods, such as the theory of Jacobi sums over finite fields and subtle treatment of some complicated combinatorial identities. 相似文献
45.
46.
化学发光—流动注射—胶束增敏连续测定钴铬研究 总被引:4,自引:0,他引:4
基于钴(Ⅱ)和铬(Ⅲ)对鲁米诺-过氧化氢化学发光反应均有催化作用,加入CTMAB能明显提高发光的信噪比,可测定亚纳克量的钴和铬,加入EDTA掩蔽钴(Ⅱ)测得铬(Ⅲ)量,再由钴和铬总量求得钴(Ⅱ)量,实现钴和铬的不经分离而流动注射连续测定。此法线性范围宽达4个数量级(10-11~10-7g/mL),检测下限低(Co2+1.2×10-11g/mL,Cr3+1.0×10-11g/mL),再现性好,工效高(120个样品/h),用于三种矿泉水中痕量钴(Ⅱ)、铬(Ⅲ)连续测定,结果良好 相似文献
47.
48.
In view of the Bailey lemma and the relations between Hecke-type sums and Appell–Lerch sums given by Hickerson and Mortenson, we find that many Bailey pairs given by Slater can be used to deduce mock theta functions. Therefore, by constructing generalized Bailey pairs with more parameters, we derive some new families of mock theta functions. Meanwhile, some identities between new mock theta functions and classical ones are established. Furthermore, based on the proofs of the main theorems, many q-hypergeometric transformations are obtained. 相似文献
49.
Daniel T. Wise 《Geometriae Dedicata》2002,94(1):215-223
We construct an example of a finitely generated
group G such that rank((G
)n)=2 for all n1. For each n, we construct a finitely presented
group G
n
such that rank((G
n
)n)=2. We conjecture that if G is a word-hyperbolic group then rank(G
n
) as $ n. For each m we give an example of a residually finite
group K
m
such that K
m
has exactly two relators, but K
m
has no proper subgroups of index $ m. We construct a finitely generated
group D such that there is an epimorphism DD×D. 相似文献
50.
唐启鹤 《中国科学A辑(英文版)》2002,45(5):632-639
The famous Embrechts-Goldie-Veraverbeke formula shows that, in the classical Cramér-Lundberg risk model, the ruin probabilities satisfy \(R(x, \infty ) \sim \rho ^{ - 1} \bar F_e (x)\) if the claim sizes are heavy-tailed, where Fe denotes the equilibrium distribution of the common d.f. F of the i.i.d. claims, ? is the safety loading coefficient of the model and the limit process is for x → ∞. In this paper we obtain a related local asymptotic relationship for the ruin probabilities. In doing this we establish two lemmas regarding the n-fold convolution of subexponential equilibrium distributions, which are of significance on their own right. 相似文献