改进的最小费用理论在盲竖井选址中的应用

在网络的任意点求解绝对中心等特殊点是网络流研究的一个难点.在目前最小费用理论的基础上引入平面几何理论,把网络等效于几何图形,建立了数学模型.通过求解,得出了网络间的最佳连接点,从而确定出盲竖井的位置.最后以云南锡业集团个旧东区两个生产平台之间的连接为一算例,得出了理想的结果,验证了该方法的有效可行性.     

Solvothermal Synthesis,Crystal Structure and Optical Property of Lanthanide Selenidostannate [{Tb（en）_3}_2（μ-OH）_2]Sn_2Se_6 with a 3-D H-bonded Network

An inorganic-organic hybrid lanthanide selenidostannate [{Tb(en)3}2(μ-OH)2]Sn2Se6(1) was synthesized by the solvothermal method.1 crystallizes in the monoclinic system,space group P21/n with a=10.120(2),b=11.781(3),c=15.403(3),β=99.534(5)°,V=1811.1(7)3,Mr=1423.62,Z=2,Dc=2.611 g/cm3,μ=11.281 mm-1,F(000)=1312,S=1.101,the final R= 0.0400 and wR=0.0853 for 3242 observed reflections with Ⅰ> 2σ(Ⅰ).1 consists of a [Sn2Se6]4-and a [{Tb(en)3}2(μ-OH)2]4+ ions.The [Sn2Se6]4-anion is constructed by two SnSe4 tetrahedra sharing a common edge.The binuclear [{Tb(en)3}2(μ-OH)2]4+ complex is composed of two [Tb(en)3]3+ ions joined by two μ-OH bridging ligands.The Tb3+ ion lies in an eight-coordinated bicapped trigonal prism.In 1,the [Sn2Se6]4-and [{Tb(en)3}2(μ-OH)2]4+ moieties are connected into a 3-D network via N-H···Se and O-H···Se H-bonds.     

Synthesis and Structure of a Novel 3-Fold Interpenetrating Three-dimensional Coordination Polymer：[Ni（Hbyip~（2-））（bix）_（0.5）（H_2O）]_n

A three-dimensional coordination polymer,[Ni(Hbyip2-)(bix)0.5(H2O)]n,has been hydrothermally synthesized.Each Ni2+ ion is five-coordinated by three carboxylate O atoms from three different 5-(benzoic acid-4-yldiazenyl)isophthalate(Hbyip2-) anions,one N atom from one 1,4-bis(imidazol-1-ylmethyl)benzene(bix) ligand and one O atom from an aqua ligand displaying a distorted square-pyramid.Each Ni atom is defined by three Hbyip2-anions and each Hbyip2-anion adopts a tris(mono-dentate) ligand coordinating to three Ni2+ ions affording a 36-membered inorganic ring.These rings are further arranged into an undulated two-dimensional layer parallel to the(101) plane.Adjacent two-dimensional networks are linked by bix ligands into a three-dimensional {63,83}{63} framework with a large channel(ca.26.3 × 13.6) along the [100] direction.Each individual {63,83}{63} network interpenetrates with two others in a parallel fashion to generate a 3-fold interpenetrating network.     

全光网络的路由扩展方法

本文主要讨论了通信网络的路由创建方法,提出了一种使用节点的相邻关系来创建新路由的原理和操作步骤.在网络连接度满足一定要求后,可以重复用该方法来获得网络节点之间的所有可能路由.文章最后讨论了路由扩展方法在通信网络创建路由时的使用方法.     

Synthesis and Crystal Structure of the Ring-opening of Amino-oxazoline

The compound C12H19Cl2N20·1/2H2O was obtained as the by-product of synthesizing silylene-bridged amino-oxazoline, and its structure was determined by X-ray diffraction. The crystal is of triclinic, space group P1, with a = 12.132（5）, b = 12.231（5）, c = 16.435（6） A^°, α = 97.485（8）, β = 106.106（7）,γ = 98.538（7）°, λ = 0.7103 A^°, V = 2279.0（15）A^°3, Z = 6, Dc = 1.251 g/cm^3, Mr = 286.19, F（000） = 906, R = 0.0846 and wR = 0.2295 for 6290 observed reflections with I 〉 2σ（I）. It is a Cl-salt. The compound was composed of phenyl, amino ion and amido derivatives. The aforementioned components were held together into a complicated three-dimensional network through three types of hydrogen bonding interactions.     

Partitioning a graph into defensive <Emphasis Type="Italic">k</Emphasis>-alliances

A defensive k-alliance in a graph is a set S of vertices with the property that every vertex in S has at least k more neighbors in S than it has outside of S. A defensive k-alliance S is called global if it forms a dominating set. In this paper we study the problem of partitioning the vertex set of a graph into (global) defensive k-alliances. The (global) defensive k-alliance partition number of a graph Θ = (V, E), (ψ _k ^gd (Γ)) ψ _k ^d (Γ), is defined to be the maximum number of sets in a partition of V such that each set is a (global) defensive k-alliance. We obtain tight bounds on ψ _k ^d (Θ) and ψ _k ^gd (Γ) in terms of several parameters of the graph including the order, size, maximum and minimum degree, the algebraic connectivity and the isoperimetric number. Moreover, we study the close relationships that exist among partitions of Γ₁ × Γ₂ into (global) defensive (k ₁ + k ₂)-alliances and partitions of Γ _i into (global) defensive k _i -alliances, i ∈ {1, 2}.     

可信网络连接中一种基于可信度的细粒度授权模型

针对可信网络连接架构中所定义的访问控制粒度粗、对于如何评估访问请求者的可信级别,如何实施授权访问没有定义等问题,提出了根据请求者的行为及其平台计算环境特征评估其信任级别的方法,研究了具有反馈功能的动态访问授权模型,并在构建可信网络连接原型系统的基础上,实现了从连接到授权的接入控制和动态调整.     

The pants sum of high distance Heegaard splittings简

Let Mi be a compact orientable 3-manifold, and Fi be an incompressible surface on δMi, i -= 1,2. Let f ： F1 →F2 be a homeomorphism, and M = M1 UI M2. In this paper, under certain assumptions for the attaching surface Fi, we show that if both M1 and M2 have Heegaavd splittings with distance at least 2（g（M1）＋ g（M2））＋ 1, then g（M） = g（M1）＋g（M2）.