中立型脉冲微分方程正解的存在性

本文利用Banach压缩映射原理，讨论了中立型时滞脉冲微分方程正解的存在性。     

权马尔可夫链在人口死亡率时序误差预测中的应用

针对人口死亡率时间序列既有摆动又有一定趋势的特点,首先对人口死亡率的时间趋势项进行拟合,然后对人口死亡率的误差序列进行分析,提出了以规范化的自相关系数为权,用加权的马尔可夫链来预测人口死亡率状况。并通过实例对该方法进行了具体的应用。     

An efficient adaptive analysis procedure for node-based smoothed point interpolation method (NS-PIM)

This paper presents an efficient adaptive analysis procedure being able to operate in the framework of the node-based smoothed point interpolation method (NS-PIM). The NS-PIM uses three-node triangular cells and is very easy to be implemented, which make it an ideal candidate for adaptive analysis. In the present adaptive procedure, a new error indicator is devised for NS-PIM settings; two ways are proposed to calculate the local critical value; a simple h-type local refinement scheme is adopted and Delaunay technology is used for regenerating optimal new mesh. A number of typical numerical examples involving stress concentration and solution singularities have been tested. The results demonstrate that the present procedure achieves much higher convergence rate results compared to the uniform refinement, and can obtain upper bound solution in strain energy.     

Synthesis, crystal structure and spectroscopic properties of two new complexes containing azido or dicyanamido bridges

Two new complexes, [Cu(L₁){N(CN)₂}]·ClO₄ (1) (L₁ is 1,8-dimethyl-1,3,6,8,10,13-hexa-azacyclotetradecane) and [Co(L₂)(N₃)₂]·ClO₄ (2) (L₂ is 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetra-azacyclotetradecane) have been synthesized and characterized. The compounds crystallize in the monoclinic system P2₁ space group for 1 and P2₁/n for 2. Single crystal X-ray analysis reveals that the compound 1 assumes a one-dimensional structure via hydrogen-bonding interactions, in which each Cu(II) ion is coordinated by four nitrogen atoms from ligand L₁ and one nitrogen atom from [N(CN)₂]⁻ anion. For compound 2, each Co(III) ion is coordinated by four nitrogen atoms of ligand L₂ and two nitrogen atoms from N₃ ⁻ anion.     

混合互补问题牛顿型算法的二阶收敛性

在凸规划理论中,通过ＫＴ条件,往往将约束最优化问题归结为一个混合互补问题来求解。该文就正则解和一般解两种情形分别给出了求解混合互补问题牛顿型算法的二阶收敛性的充分性条件,并在一定条件下证明了非精确牛顿法和离散牛顿法所具有的二阶收敛性。     

一类含非保守瞬时态的Q－矩阵

既含瞬时态又含稳定态的Ｑ－矩阵的研究比较困难，目前国内外已有的结果不多，且大部分是在Ｑ保守的条件下给出。本文对瞬时态非保守的矩阵Ｑ．给出了存在Ｑ过程的一个充分条件，此条件直接加在矩阵Ｑ上，比较容易检验。应用本文结果，可直接导出［６］中主要结论的充分性的证明。     

保费随机收取的广义二元复合非齐次Poisson风险模型

研究了一类双险种风险模型,其中索赔到达计数过程和保费到达计数过程均为非齐次Po isson过程,用鞅方法得到了有限时间破产概率的一个上界,并给出了当两个险种的个体索赔均服从指数分布时,有限时间破产概率的上界估计.     

双参数六点细分法

提出了一类包含两个形状参数的双参数六点细分法,可以构造光滑插值曲线和光滑逼近曲线,并且可以通过对两个参数取值的调整使得曲线达到一致收敛,C1或C2.讨论了形状参数对细分法的收敛性及连续性的影响,给出了细分法一致收敛、C1连续、C2连续的充分条件,并给出了一些数值算例.     

基于深孔改进电极发射光谱法同时测定地球化学样品中微量银、锡、硼

采用深孔改进电极,一米平面光栅交流电弧摄谱法同时测定地球化学样品中微量银、锡、硼的含量。以三氧化二铝、硫酸钾、氟化钠和碳粉作缓冲剂,锗作内标。方法检出限为:银0.015μg/g、锡0.32μg/g、硼1.0μg/g,相对标准偏差(RSD)为5.8%~7.5%。实验用国家一级标准物质进行验证,方法的测定值与标准值相符。     

一类上、下限互为倒数的定积分计算方法

本文利用对数函数变换简便地解决了积分上、下限互为倒数的一类定积分计算问题．