“三焦点”广义椭圆曲线及其传导特性

提出了三焦点广义椭圆的概念,给出了三焦点广义椭圆的画法及其轨迹方程,建立了三焦点广义椭圆的重心M到三焦点广义椭圆轨迹曲线上动点P的距离d的数学模型,研究了三焦点广义椭圆构件对力与速度的传动特性及其在工业上的应用.     

BCH-代数的Ω-模糊点理想

引入BCH-代数的Ω-模糊点理想的概念,给出了它的几个实例,研究了它们的一些性质.讨论了Ω-模糊理想与Ω-模糊点理想的关系,获得了Ω-模糊点理想的几个等价描述,研究了Ω-模糊点理想的同态像与同态原像的性质,给出了BCH-代数的Ω-模糊点理想与BCH-代数之积代数的Ω-模糊点理想的关系, 讨论了模糊点理想与Ω-模糊点理想之间的相互构造.     

基于HBP估计的宏观经济统计数据诊断方法实证研究

HBP估计是具有高失效点的稳健估计方法,根据生产函数模型,利用LMS和MCD估计方法对浙江省相关年份的GDP进行了定量诊断,发现研究期间的GDP存在异常点和高杠杆点,并对异常点进行了验证,对高杠杆点进行了分析,解释了高杠杆点的产生原因。同时利用RLS估计方法对模型进行回归,根据回归结果对异常点进行了修正。     

各种停点及其关系

给出 了一个 尽可能 完善 的各种 停点的 关系． 仿照 Ｂａｋｒｙ 引 入 ｉ强停点, 对亚强 停点 本文给出了它的准 确位置,它处于 停点和强停点之 间,且可以像停 点和强停点一样 用停时点来刻画     

椭圆曲率中心轨迹——星形线的特性

采用微分几何方法分析了椭圆星形线的多项特性,指出了其中星形线划分平面的特性对于椭圆上的点离已知点距离极值存在性的决定性作用,同时指出了星形线划分平面的特性对于确定椭圆上距离任意已知点最远或最近的点的位置具有决定性意义,提出了确定最远点及最近点的几何方法,阐明了最远点及最近点在各极值点之间的替换过程,为工程中确定圆柱面绕任意轴回转所形成的包络面的特性提供了依据.     

从1999年高考（24）题看多动点轨迹的求法

任何一个轨迹问题，不论动点多少，总可以分为二大类，即主动点(在一定条件下可以相对自由运动的点)与从动点(随主动点运动而运动的点)．多动点轨迹问题的本质是，由主动点的运动规律探求从动点的轨迹．一般地，在多动点轨迹问题中，主动点往往不止一个，这就使从动点与主动点的相互运动增加了复杂性．如何恰当设置变元，     

有效点、弱有效点和真有效点的锥刻画

利用集合在某点的相依切锥、法向锥和可行方向锥等研究向量优化问题的有效点、 弱有效点和真有效点的特征,对局部有效点、局部弱有效点和局部真有效点与集合的各 锥之间的关系作了刻画.     

基于点截集的围堵嫌犯模型

研究了在突发事件中交巡警对在逃嫌犯的围堵问题, 该问题为2011年全国大学生数学建模竞赛B题的一部分。接到报警后,交巡警服务平台的警力需要指派到路网路口以堵截嫌犯。将该问题转化为阻止嫌犯逃到特定点集的问题;并分析了怎样判断被选为围堵点的点集对一个指定点形成包围的问题。推广了点截集的概念,给出了判断点集是否为点截集和紧点截集的优化模型。然后将判断是否为点截集的模型转换为约束集合, 用于建立围堵嫌犯模型,以四个不同的优化标准分别建立了围堵问题的0-1整数规划模型。并给出了部分模型的Lingo算例。     

多指标决策广义双基点法

在多指标决策双基点法中,指出了已有方法的不足,基于靠近理想点和远离负理想点这两个基准,本文定义了一种新的相对贴近度的计算公式,由此给出了一种广义双基点法.     

线性回归模型中的后验影响函数

本文对线性回归模型定义了后验影响函数;针对已有的先验信息的三种不同情况给出了它的分解式,讨论了其优良性;指出强影响点、异常点、高杠杆点的内在联系,讨论了上述三种点的探测方法。     

Mathematical Instantons in Characteristic Two

On P³, we show that mathematical instantons in characteristic two are unobstructed. We produce upper bounds for the dimension of the moduli space of stable rank two bundles on P³ in characteristic two. In cases where there is a phenomenon of good reduction modulo two, these give similar results in characteristic zero. We also give an example of a nonreduced component of the moduli space in characteristic two.     

模糊数四则运算的交点-间断点法

对模糊数的四则运算提出了一种交点-间断点法:将模糊数的加法、减法和除法运算,化为求两个函数在某区间上其交点处的值;当交点不存在且两函数在该区间上的间断点为有限个时,将其运算化为求一函数在这些间断点处及区间的两端点处的最大值;将模糊数的乘法运算,化为用交点法或间断点法分别在两个区间上求出相应的值,然后取它们中最大者。     

On two inequalities similar to Opial's inequality in two independent variables

In the present paper we establish two new integral inequalities similar to Opial's inequality in two independent variables. The inequalities established in this paper are similar to the analogues of Calvert's generalizations of Opial's inequality, in two independent variables and contains in the special case the analogue of Opial's inequality given by G. S. Yang in two independent variables.     

不完全信息动态二维价格博弈模型及其分析

单位生产成本为不完全信息条件下,本文首先讨论了两个企业关于具有一定替代性的两种产品价格的动态二维博弈模型,并求得其精练Bayes均衡.然后分析了当两种产品不存在替代关系时,企业对这两种产品价格进行动态博弈的精练Bayes均衡相当于对这两种产品单独进行博弈的精练Bayes均衡的简单组合.     

Convergence Analysis for the Iterated Defect Correction Scheme of Finite Element Methods on Rectangle Grids

This paper develops a new method to analyze convergence of the iterated defect correction scheme of finite element methods on rectangular grids in both two and three dimensions. The main idea is to formulate energy inner products and energy (semi)norms into matrix forms. Then, two constants of two key inequalities involved are min and max eigenvalues of two associated generalized eigenvalue problems, respectively. Local versions on the element level of these two generalized eigenvalue problems are exactly solved to obtain sharp (lower) upper bounds of these two constants. This and some essential observations for iterated solutions establish convergence in 2D and the monotone decreasing property in 3D. For two dimensions the results herein improve those in literature; for three dimensions the results herein are new. Numerical results are presented to examine theoretical results.     

Existence of solutions of two generalized riccati operator equations and their representation

The solutions of two generalized Riccati operator equations are discussed in terms of two critical parameter values, which are related to the application of optimal control under unknown disturbances. Explicit formulas for calculating these two critical parameters as well as the closedform solutions of these two generalized Riccati operator equations are given. The connection between these two parameters and a zero-sum differential game is also investigated.     

Polygon vertex extremality and decomposition of polygons

In this paper, we show that if we decompose a polygon into two smaller polygons, then by comparing the number of extremal vertices in the original polygon versus the sum of the two smaller polygons, we can gain at most two globally extremal vertices in the smaller polygons, as well as at most two locally extremal vertices. We then will derive two discrete Four-Vertex Theorems from our results.     

Influences of migrations from local competitive pressures on populations between patches

A mathematical model of two competitive populations with migrations between two patches is proposed, which incorporates the dispersals produced by local competitive pressures. It is shown that the density-dependent migrations enhance the persistence of the two competitive populations. Compared with constant migrations, the dispersals from local competitive pressures induce dramatic changes of dynamical behavior of the model. First, the model admits a transition from one stable positive equilibrium to bistable positive equilibria. Second, the model exhibits bifurcations with the existence of seven positive steady states, in which two stable positive equilibria coexist with two stable boundary equilibrium points. These changes alter the distribution of the two populations in the two patches and increase their survival possibilities.     

论带有趋势变化的变量的相关:数值试验

当计算相关的二个变量都包含有明显的趋势变化成分时,原变量之间的相关特征可能被歪曲(夸大或者缩小).对此问题进行了数值试验,结果表明,变量带有性质相反的趋势变化,会使这二个变量之间的相关系数减小(正相关的数值减小,负相关被夸大).变量带有性质相同的趋势变化,会使这二个变量之间的相关系数增加(正相关被夸大,负相关数值变小).数值试验还表明,趋势变化对相关的影响具有可交换性.只要不改变它们趋势变化的数值,它们叠加的变量互相交换,影响相关系数的后果是一样的;研究还指出,二个变量有相同的变化趋势时,对相关的影响会更大些.给出了实例.     

Ruin Probabilities in Cox Risk Models with Two Dependent Classes of Business

In this paper we consider risk processes with two classes of business in which the two claim-number processes are dependent Cox processes. We first assume that the two claim-number processes have a two-dimensional Markovian intensity. Under this assumption, we not only study the sum of the two individual risk processes but also investigate the two-dimensional risk process formed by considering the two individual processes separately. For each of the two risk processes we derive an expression for the ruin probability, and then construct an upper bound for the ruin probability. We next assume that the intensity of the two claim-number processes follows a Markov chain. In this case, we examine the ruin probability of the sum of the two individual risk processes. Specifically, a differential system for the ruin probability is derived and numerical results are obtained for exponential claim sizes.