血液分组化验问题二次分组化验法最佳分组方式的算法

针对血液分组化验问题,进行了严密的数学分析和数学证明,给出了一次分组化验法最佳k_1值的简单精确计算方法;特别是通过对引理及定理3证明推导出二次分组化验法中每人平均化验次数计算公式;通过对定理4-5证明,总结出二次分组化验法最佳分组时k1和k2的计算方法.同时给出了二次分组化验法最佳分组时p与k_1和k_2对照表,以及一次分组化验法最佳分组时p与k_1对照表.     

血液化验二次分组模型的简捷算法

运用概率和微分学基本理论推导血液二次分组化验最佳分组方案,给出确定二次分组化验最佳分组组数和最佳分组人数的方法,并将血液二次分组化验最佳分组方式与一次分组化验进行比较.     

血液分组化验模型的解的结构研究

针对相关文献建立的血液分组化验模型,通过数理分析借助Mathematica软件分别研究一次分组化验模型和二次分组化验模型的解的结构特征.     

分组化验模型的优化研究

本文研究了血液的分组化验模型.利用概率和微分学基本理论证明了当血样呈阳性的概率在某一确定范围时,分组化验存在最佳分组方案,针对给定的血样阳性概率给出了最佳分组k值的确定方法,得出了分组化验最佳分组k值计算公式.     

血样二次分组检验的探讨

提出了血样的二次分组检验方法,建立了二次分组验血法预期人均检验次数最小的模型,给出了二次分组法的最佳小组人数和最佳小组数的范围,得到了求二次分组最佳方案的方法.计算结果表明模型和方法是可信的,在单个人血样呈阴性概率较大时,采用二次分组验血法能比一次分组验血法更进一步地减少检验次数,有较大的实用价值.     

关于分组化验模型的一个猜想

运用概率和微分学基本理论推导出分组化验法的适用范围,给出最佳分组的存在性证明,并提出最佳分组人数的一个猜想.     

血液分组化验法的简洁数学证明及简单精确计算方法

给出了血液分组化验中p值存在区间及对应最佳K值所在区间,给出了最佳K值简单精确计算方法,同时作了简洁严密数学证明,并用一个函数式将所研究结果准确表达.     

二分法在血样分组检验中的应用

提出了利用二分法对血样进行分组检验,建立了基于二分法分组方法的人均检验次数上限的数学模型,通过数值模拟给出了二分法的适用范围.计算结果表明,在单个人的血样呈阳性的概率较小且检验人数较多时,相比一次分组和二次分组验血法,采用二分法能更进一步地减少人均验血次数.     

分组化验问题

问题1:在某1000个人中有10个人患有一种病,现要通过验血把这10个病人查出来,若采用逐个人化验的方法需999次(这里所需的化验次数是指在最坏情况下的化验次数,如果碰巧,可能首先化验的10个人全是病人,10次化验就够了.下面讨论的次数均是指最坏情况下的化验次数)为了减少化验次数,人们采用分组化验的方法,即把n个人的血样混在一起,先化验一次,若化验合格,则这n个人全部正常,若混合血样不合格,说明这n个人中有病人,再对它们重新化验(逐个化验,或再分组化验).……     

分组化验的优化模型

依据数学理论证明在一定条件下,通过分组化验的方法可以减少化验次数;并给出了选择方法;建立了一个减少化验次数的优化模型.     

Group connectivity and group colorings of graphs — A survey

In 1950s, Tutte introduced the theory of nowhere-zero flows as a tool to investigate the coloring problem of maps, together with his most fascinating conjectures on nowhere-zero flows. These have been extended by Jaeger et al. in 1992 to group connectivity, the nonhomogeneous form of nowhere-zero flows. Let G be a 2-edge-connected undirected graph, A be an (additive) abelian group and A* = A − {0}. The graph G is A-connected if G has an orientation D(G) such that for every map b: V (G) ↦ A satisfying Σ _v∈V(G) b(v) = 0, there is a function f: E(G) ↦ A* such that for each vertex v ∈ V (G), the total amount of f-values on the edges directed out from v minus the total amount of f-values on the edges directed into v is equal to b(v). The group coloring of a graph arises from the dual concept of group connectivity. There have been lots of investigations on these subjects. This survey provides a summary of researches on group connectivity and group colorings of graphs. It contains the following sections.

An Adjacency Criterion for the Prime Graph of a Finite Simple Group

For every finite non-Abelian simple group, we give an exhaustive arithmetic criterion for adjacency of vertices in a prime graph of the group. For the prime graph of every finite simple group, this criterion is used to determine an independent set with a maximal number of vertices and an independent set with a maximal number of vertices containing 2, and to define orders on these sets; the information obtained is collected in tables. We consider several applications of these results to various problems in finite group theory, in particular, to the recognition-by-spectra problem for finite groups. Supported by RFBR grant No. 05-01-00797; by the Council for Grants (under RF President) and State Aid of Fundamental Science Schools, project NSh-2069.2003.1; by the RF Ministry of Education Developmental Program for Scientific Potential of the Higher School of Learning, project No. 8294; by FP “Universities of Russia,” grant No. UR.04.01.202; and by Presidium SB RAS grant No. 86-197. __________ Translated from Algebra i Logika, Vol. 44, No. 6, pp. 682–725, November–December, 2005.     

On the Rank of Picard Groups of Modular Varieties Attached to Orthogonal Groups

We derive lower bounds for the rank of Picard groups of modular varieties associated with natural congruence subgroups of the orthogonal group of an even lattice of signature (2, l). As an example we consider the Siegel modular group of genus 2. The analytic part of this paper also leads to certain class number identities.     

Class groups of imaginary function fields: The inert case

Let be a finite field and a transcendental element over . An imaginary function field is defined to be a function field such that the prime at infinity is inert or totally ramified. For the totally imaginary case, in a recent paper the second author constructed infinitely many function fields of any fixed degree over in which the prime at infinity is totally ramified and with ideal class numbers divisible by any given positive integer greater than 1. In this paper, we complete the imaginary case by proving the corresponding result for function fields in which the prime at infinity is inert. Specifically, we show that for relatively prime integers and , there are infinitely many function fields of fixed degree such that the class group of contains a subgroup isomorphic to and the prime at infinity is inert.

     

PROOF OF A CONJECTURE RELATED TO THE PARABOLIC CLASS NUMBERS OF SOME FUCHSIAN GROUPS

This paper proves a conjecture given in [6], which is concerning with the parabolic class numbers of some Fuchsian groups.     

幂零群中非正规循环子群的共轭类数

设G是有限幂零群,v~*(G)是其非正规循环子群的共轭类数,则下列结论之一成立：(1) v~*(G)≥c(G)-1；(2)G是Hamilton群；(3)G中存在正规子群K使K/Z(K)有一个同态像与二面体群D(2~n),n≥3或C_2×C_2同构．