COVERING TWO DIGRAPHS WITH ARBORESCENCES

Let G_1 and G_2 be finite digraphs,both with vertex set V.Suppose that each vertexv of V has nonnegative integers f(v) and g(v) with f(v)≤g(v),and each arc e of G_4 hasnonnegative integers a_i(e) and b_i(e) with a_i(e)≤b_i(e),i=1,2.In this paper we give anecessary and sufficient condition for the existence of k arborescences in G_4 covering each are(?) of G_i at least a_i(e) and at most b_i(e) times,i=1,2,and satisfying the condition that foreach v in Vf(v)≤r_1(v)=r_2(v)≤g(v)where r_4(v) denote the number of the arborescences in G_(?) rooted at v.     

关于树形图结构的智能化研究

为了促进树形图结构的智能化研究,通过引入零元的概念将树形图结构转化为格结构,证明了加入零元的树形图可在给定序关系下构成格,进而将格的有关理论引入树形图的逻辑运算中。探讨了格的有关理论在树形图结构表示、逻辑运算等方面的应用,给出了基于格论的树形图表示方法等许多相关结论。这些结论对树形图结构的智能化研究具有一定意义。     

PACKING A TREE OF ORDER p WITH A （p,p＋1）—GRAPH

Let G1 and G2 be two graphs of the same order,If G1 is isomorphic to a spanning subgraph of the complement of G2,then we say that G1 and G2 are packable.A graph G is called a (p,m)-graph if G has p vertices and m edges.The main purpose of this paper is to present a necessary and sufficient condition for a tree of order p and a (p,p 1)-graph to be packable.     

COORDINATING PRODUCTION AND RECYCLING DECISIONS WITH STOCHASTIC DEMAND AND RETUR

In this paper, the joint production and recycling problem is investigated for a hybrid manufacturing and remanufacturing system where brand-new products are produced in the manufacturing plant and recycled products are remanufactured into as-new products in the remanufacturing facility. Both the brand-new products and remanufactured products are used to satisfy customer demands. Returns of used products that are recycled from customers are assumed to be stochastic and nonlinearly price-dependent. A mathematical model is proposed to maximize the overall profit of the system through simultaneously optimizing the production and recycling decisions, subject to two capacity constraints ? the manufacturing capacity and the remanufacturing capacity. Based on Lagrangian relaxation method, subgradient algorithm and heuristic algorithm, a solution approach is developed to solve the problem. A representative example is presented to illustrate the system, and managerial analysis indicates that the uncertainties in demand and return have much influence on the production and recycling policy. In addition, twenty randomly produced examples are solved, and computational results show that the solution approach can obtain very good solutions for all examples in reasonable time.     

基于功能的系统关键要素识别

系统的总体功能是由各系统要素提供的功能实现的。哪些系统要素对于达到总系统的目标功能是关键的,对于系统的优化至关重要。本文在系统关键要素概念的基础上,利用图论理论和矩阵理论,研究了系统关键要素的识别过程,并针对不同的系统基本结构,得出了相应的推论。最后,通过实例说明了系统关键要素判定定理的实用性。     

带有交货期窗口的调度问题及算法

对不同交货期窗口下的提前／拖期单机调度问题进行了分析,给出了最优序列中相邻工件对所满足的必要条件,提出了两个优先级法则,并利用优先级法则设计出遗传算法的交叉算子,在文章的最后,给出了实验结果和结论．     

A Table Based Algorithm for Minimum Directed Spanning Trees

1. INTRODUCTIONSeveral optimal spanning tree methods have been developed for the weighted undirected graph. The commonlyused methods are Kruskal's method (also called Greedy algorithm) and Disorder algorithm [4]. As for theweighted digraph, little work has been done [1]. In practice, the complicated digraph is difficult to be depicted,but easy to be expressed in the form of a table. Based on the table expression instead of the digraph expression,an optimal spanning rooted-tree method cal…     

Table Operation Method for Optimal Spanning Tree Problem

1.INTRODUCTIONSeveraloptimalspanningtreemethodshavebeendevelopedfortheweightundirectedgraph.ThecommonlyusedmethodsareKruskal'sMethod[4](alsocalledGreedyAlgoritlun)andDisorderAlgorithm[4j.Asfortheweightdigraph,littleworkhasbeendone.Inthepractice,thecomplicateddigraphisdifficulttodepict,butitiseasytobeexpressedintheformofatable.Basedoilthetableexpressioninsteadofthedigraphexpression,thispaperdevelopsanoptimalspanningrooted-treemethodcalledtableoperationsmethod(TOM).2.SOMEBASICCONCE…     

LOCAL AND GLOBAL BIFURCATIONS AND APPLICATIONS IN A PREDATOR-PREY SYSTEM WITH SEVERAL PARAMETERS

A predator-prey system,depending on several parameters,is investigated forbifurcation of equilibria,Hopf bifurcation,global bifurcation occurring saddle connection,and global existence and nonexistence of limit cycles,and changes of the topological structureof trajectory as parameters are varied.     

LINEAR COMPLEXITY AND RANDOM SEQUENCES WITH PERIOD 2~n

Let (?)=(S,S,…)be a binary random sequence with period N=2~n,where S=(S_0,…,S_(N-1))is its one period with N independent and uniformly distributed binary random variables.The main results of this paper are as follows.1)Var c(?)=2-(2N+1)2~(-N)-2~(-2N);2)E|c(?)-c(?)|=[2~(c(?)+1)-2]2~(-N)for any sequence (?) with period 2~n;3)N-1+2~(-N)-(n/2+1-2~(-(N-n)))≤E[(?)c(?)]≤N-1+2~(-N)4)2-2~(-(N-1))≤E[(?)|c(?)-c(?)|]≤2-2~(-N)+n/2-2~(-(N-n)),where E and Var stand for taking expectation and variance respectively,c(?) is the linearcomplexity of the sequence (?) and W(b) the Hamming weight of one period of the seqnence (?).     

GLOBAL ATTRACTIVITY OF POPULATIONMODELS WITH DELAYS AND DIFFUSION

In this paper, the asymptotic behavior of three types of population models with delays and diffusion is studied. The first represents one species growth in the patch Ω and periodic environment and with delays recruitment, the second models a single species dispersal among the m patches of a heterogeneous environment, and the third models the spread of bacterial infections. Sufficient conditions for the global attractivity of periodic solution are obtained by the method of monotone theory and strongly concave operators. Some earlier results are extended to population models with delays and diffusion.     

LIMIT THEOREMS AND OPTIMAL DESIGN WITH ADAPTIVE URN MODELS

In this paper we study urn model, using some available estimates of successes probabilities, and adding particle parameter, we establish adaptive models. We obtain some strong convergence theorems, rates of convergence, asymptotic normality of components in the urn, and estimates. With these asymptotical results, we show that the adaptive designs given in this paper are asymptotically optimal designs.     

基于随机来水量随机负荷的短期水火电调度

本文利用随机变量计及自然来水量及负荷的不确定性，用机会约束来描述水库蓄水量约束及线路的安全约束，并通过两阶段随机线性规划求解本文模型．本文最后给出了一样例系统的计算结果．     

ESTIMATION AND INFERENCE FOR VARYING-COEFFICIENT REGRESSION MODELS WITH ERROR-PRONE COVARIATES

This paper studies the estimation and inference for a class of varying-coefficient regression models with error-prone covariates. The authors focus on the situation where the covariates are unobserved, there are no repeated measurements and the covariance matrix of the measurement errors is unknown, but some auxiliary information is available. The authors propose an instrumental variable type local polynomial estimator for the unknown varying-coefficient functions, and show that the estimator achieves the optimal nonparametric convergence rate, is asymptotically normal, and avoids using undersmoothing to allow the bandwidths to be selected using data-driven methods. A simulation is carried out to study the finite sample performance of the proposed estimator, and a real date set is analyzed to illustrate the usefulness of the developed methodology.     

MODELLING AND STABILITY ANALYSIS OF POPULATION GROWTH WITH SPATIAL DIFFUSION

In recent years, population growth models with spatial diffusion have beenextensively studied by many authors (for example, see [1-5]). In this paper, a populationgrowth model is considered with a discrete age-dependence and spatial diffusion, and isinvestigated in a semigroup framework. The spectral properties of the population oper-ator are given. On the basis of such spectral consideration, the asymptotic behaviourof the semigroup generated by the population operator is obtained. Finally, a nonlinearpopulation growth model is considered and its stability is analyzed.     

兼容多个综合评价方案及其分类的数学模型

本文研究的模型、是与多种综合评价方法的样品排序有最大相关和综合定样品排序分类时具有最小差异的新评价模型,这些模型已应用于综合广州市工业企业５０强中。     

NONMRAMETRIC AND SEMIPARAMETRICREGRESSION MODELS WITH LOCALLYGENERALIZED GAUSSIAN ERROR

1.IntroductionLetpbeanaturalnumberandAbeacompactsetinW,K(")~g(xj")) e(")ti~1)2,...5acwherexln),x;n),''t.in)EAaredesignpoints,gisanunknownfunction,ej")arerandomerrors.Georgiovil]definedg.(x)~fWu.(x)K(")asanestimateofg,whereWei(x)=i=1Wei(x,xl"),xln),''5x;…     

SINGLE-PERIOD TWO-PRODUCT INVENTORY MODEL WITH SUBSTITUTION:SOLUTION AND PROPERTIES

In this paper, we study a single-period two-product inventory model with stochastic demands and downward substitution. The optimal order quantities are presented and some properties are provided. Comparing with newsboy model, we prove that both the profit and the fill rate can be improved by using the substitution policy.     

RELIABILITY BOUNDS IN NWUE CLASS WITH KNOWN MEAN AND VARIANCE

Let. F∈NWUE with known mean and variance. In this note a simple sharplower bound of F=1-F(t) is given.     

基于线性约束的系数矩阵可调的管理决策NLP模型

本文是文献［１］的继续，依据约束理论原理，给出了当系数矩阵Ａ可调时，确定线性约束Ａｘ≤ｂ的并行管理决策ＮＬＰ模型的“瓶颈”约束元素的定量方法，并提出了通过“松弛”瓶颈约束以有效地提高管理决策的整体综合效益的管理决策流程