雷达极化理论中常见极化散射矩阵特性分析

介绍了雷达极化理论中常见的辛克莱(Sinclair)散射矩阵、米勒(Mueller)散射矩阵、格雷伍斯(Graves)功率散射矩阵等极化散射矩阵,并对其特性进行了较详尽的分析。导出了上述各种极化散射矩阵间的相互变换关系式,从而为其在雷达目标检测和识别领域中的应用提供了相应的理论依据.     

基于林业部门的中国宏观社会核算矩阵构建

森林碳汇在应对气候变化中的重要作用越来越突显。用可计算一般均衡模型(CGE)分析碳汇政策能够为政策的制订提供强有力的依据,构建CGE模型的前提需要构建基于林业部门的社会核算矩阵(SAM)。SAM中的林业产出和投入各账户、林产品供给和需求各账户,以及隐含的相对价格可以用来模拟碳汇政策对林业的影响。基于《2007年中国投入产出表》并结合其他统计数据,编制了基于林业部门的2007年中国社会核算矩阵。该表的特点是对涉及林业的账户进行了核算,对统计年鉴中没有的数据进行了合理的估算。编制的SAM为CGE模型的构建与应用提供了数据基础。     

Optimal block designs for three treatments when observations are correlated

E$E$-optimal designs for comparing three treatments in blocks of size three are identified, where intrablock observations are correlated according to a first order autoregressive error process with parameter ρ∈(0,1)$\rho \in (0,1)$. For number of blocks b   of the form b=3n+1$b=3n+1$, there are two distinct optimal designs depending on the value of ρ$\rho$, with the best design being unequally replicated for large ρ$\rho$. For other values of b$b$, binary, equireplicate designs with specified within-block assignment patterns are best. In many cases, the stronger majorization optimality is established.     

状态转移矩阵的若干性质

给出了有限域上的状态转移矩阵 ,讨论了其周期、特征根与特征向量的一些性质     

GM模型的病态性问题

本文指出GM模型的方程组存在着严重的方程病态性问题,探讨了GM模型产生病态的原因:(1)矩阵由累加数构成,累加数之间有较大的数量级差别;(2)GM模型中的蜕化使矩阵中元素数量级差别过大;(3)GM模型的矩阵生成方式使得我们难以降低方程组的病态性。并对一个被广泛引用的算例进行了分析。最后,我们认为必须小心使用GM模型。     

Conditional tests in a competing risks model

Testing for equality of competing risks based on their cumulative incidence functions (CIFs) or their cause specific hazard rates (CSHRs) has been considered by many authors. The finite sample distributions of the existing test statistics are in general complicated and the use of their asymptotic distributions can lead to conservative tests. In this paper we show how to perform some of these tests using the conditional distributions of their corresponding test statistics instead (conditional on the observed data). The resulting conditional tests are initially developed for the case of k = 2 and are then extended to k > 2 by performing a sequence of two sample tests and by combining several risks into one. A simulation study to compare the powers of several tests based on their conditional and asymptotic distributions shows that using conditional tests leads to a gain in power. A real life example is also discussed to show how to implement such conditional tests.     

若干元不许自身3个相连的重复n排列的计数

讨论了ｒ元的ｎ重复排列,其中有ｓ个元的每人一个不许３个相邻的问题,作为应用,又讨论了３＊ｎ广义棋盘的２染色问题。     

基于活动──组织流程图的业务过程重构方法

将原有的支持BPR的活动流程图和组织流程图结合起来,提出一种基于活动—组织流程图的、人机交互式的企业业务过程重构方法．该方法利用图的邻接矩接和可达矩阵,可以方便地找出业务流程中的不合理部分,从而为大规模系统的业务过程改造提供了一种有效的工具．方法应用于某钢铁公司的物资管理系统的流程改造,取得了满意的效果．     

有限域上的一类方程组

给出了有限域Fq 上一类方程组∑ski =1 akix1d(k)i1 ……xnd(k)in =bk ,k =1,… ,m的解数公式及其求解方法 ,这里di1(k) ,… ,din(k) >0 ,aki∈Fq ,bk∈Fq,k =1,… ,m ,i=1,… ,sk.     

格序置换群的左弱可迁性

引进了格序置换群的左弱 2 -可迁和左高弱可迁 ,给出了格序置换群左弱 2 -可迁的等价条件和左高弱可迁的充要条件 .