自由群的直积的检验元素的注记

本文研究了自由群的直积的检验元素,通过对直积的自同态的分解,得到了直积中的元素为检验元素的充分必要条件,改进了O'neill和Turner的结果.此外,构造了两类具体的检验元素.     

基于GRA-DEA模型的有关农民收入的九城市的评价

有关农民收入,文章以山西省九个城市为例进行了评价.首先用灰色关联分析法分析了2016年这些城市的有关数据,筛选出影响农民收入的主要因素;其次构建了指标体系,利用数据包络分析法对有关农民收入九个城市进行了DEA有效性评价;再次对非DEA有效的城市,借助投影公式探索了改进方法;最后得出了九城市分为两类的结论,提出了针对性的建议.     

幂格与商格的关系的注记

研究了分配格上的幂格,给出了格的相对凸子格的概念,得到了分配格上的幂格的一个充要条件,建立了幂格与商格的联系.     

环的投射自由性的研究

引进了两类新环,进而研究了其投射自由性,得到了群环上的模结构,推广了Quillen-Suslin定理.     

关于特征值的平方和的注记

探讨了特征值的平方和这一计算问题,指出了常用方法的不足之处,并在深入研究方阵相似的基础之上弥补了这一不足,彻底解决了这一问题,此外运用这种方法还能解决特征值高次幂之和与多项式之和的计算问题.最后文中给出了一种新的计算特征值平方和的方法,这种方法能够回避第一种方法的不足,但缺点是不易推广.     

含有共轭三键的高聚物的掺杂机制的探讨

本文从实验事实出发,对含有共轭三键的共轭高聚物——聚丁二炔的掺杂及电导的特点进行了详细的分析;对聚丁二炔晶体掺杂的机制进行了初步的探讨;从结构相变的角度出发,提出了一个掺杂模型,并从能量的角度估算了由于掺杂引起链段结构改变所需的能量,较好地解释了聚丁二炔晶体掺杂未取得成功的原因.     

由自然数的因子构成的半群

本文首先介绍了半群、群的定义,研究了自然数n取何值时,通过定义相应的代数运算,使得它的因子集构成半群、群,从而为半群的代数理论提供了一个有趣的实例.     

基于小波变换的信号突变检测的方法

本文利用高斯函数的正整数阶导函数的一个性质,给出了一种探测信号奇异性的方法,得到了奇异点的位置,阶数α以及相应的平滑因子a和k,推导出了α满足的方程,对文献[8]的结论进行了推广.最后进行了数值试验,相对Mallat定理的10%的误差,取得了较好的效果.     

基于灵敏性分析的Q-MSGSID的优化及应用

本文针对绝对关联度、综合关联度以及相对关联度的取值范围存在的不足,首先,设置了控制因子λ以及空间中的距离d,以此来调节关联度值的范围,建立了新模型。其次,研究了它的一些性质,并在理论上证明了新模型满足灰色关联公理。另外,提出了新模型的准优值所满足的几个原则,并结合灵敏性分析原理给出了准优值的算法步骤。最后,通过实例研究,验证了新模型所得结果不但能够使关联度的值扩充到(0,1]这一更大的范围,而且提高了区分度和分辨效果。     

标准体系的使用期的模型与分析

本文提出了关于标准体系使用期的两个模型。首先定义了标准使用期,然后讨论了模型的合理性。通过模型讨论了标准使用期的性质,给出了数值示例。提出了需进一步研究的问题。     

Existence and uniqueness of solutions to a class of singular diffusion problems

Existence, uniqueness, and non-uniqueness results are given for a class of singular diffusion problems with variable diffusion rates. Continuity arguments are used on related initial value problems to produce the existence results. Uniqueness criteria are established for different sets of hypotheses and non-uniqueness results are discussed when these hypotheses fail.     

Solvability of a class of impulsive damped vibration problems

In this paper, a class of impulsive damped vibration problems are considered. Existence results are obtained by using variational method and critical point theorem. The obtained results are also valid and new even if the impulsive damped vibration problem is reduced to impulsive Hamiltonian system and Hamiltonian system. Examples are presented to illustrate the feasibility and effectiveness of the results. Copyright © 2013 John Wiley & Sons, Ltd.     

Uniqueness of difference polynomials of meromorphic functions

In this article, we investigate the uniqueness problems of difference polynomials of meromorphic functions and obtain some results which can be viewed as discrete analogues of the results given by Shibazaki. Some examples are given to show the results in this article are best possible.     

Properties of serial kanban systems

In this paper we show some structural results of a kanban system by using results about the underlying GSMP. The main results from this connection are: dominance of allocations, optimal partition, upper and lower bounds on throughput, consistency of the IPA derivative, convexity of throughput as a function of service time parameters and concavity of throughput with respect to number of kanbans. Although the dominance and the partition results were obtained previously by sample path arguments, the proofs here are less cumbersome and generalize the earlier results. The second-order properties for kanban lines are new. These results form a basis for results in multi-product lines where proofs by sample paths require extensive notation.     

Radial stability of periodic orbits of damped Keplerian-like systems

In this paper, by using the third order approximation method, the averaging method and the theory of upper and lower solutions, we study the existence and radial stability of periodic orbits of damped Keplerian-like systems. Two different results are obtained: perturbative and global results. Our results are also applicable to the classical Keplerian-like systems.     

Meromorphic solutions of some types of complex differential-difference equations

Using Nevanlinna theory of the value distribution of meromorphic functions, we investigate the problem of the existence of meromorphic solutions of some types of complex differential-difference equations and some properties of meromorphic solutions, and we obtain some results, which are the improvements and extensions of some results in references. Examples show that our results are precise.     

Banach空间中微分包含的生存单调轨道与解的稳定性

我们在无限维空间中研究微分包含的生存W—单调轨道的存在性．基于Zorn引理，我们给出了一个逼近方法，在较弱的条件下得到了一个存在性定理，其特殊情形则包含了已有的生存定理和微分方程理论中的若干结果作为应用，我们首先研究了微分包含生存解的整体存在性，得到了整体生存理．然后我们研究了微分包含解的稳定性，得到一些新的结果．     

B值随机元阵列的完全收敛性及大数定律

该文在随机元阵列随机有界于某非负随机变量的条件下，得到了B值随机元阵列完全收敛性的一般性结论，并讨论了随机元阵列加权和的收敛性，使[5][6]中的结果得到了改进和推广．同时讨论了完全收敛性与Banach空间p型（1＜P≤2）性质的等价性，使[14]，[15]中的结果得到进一步的改进．     

一些平均值的比较

利用关于广义平均值进行比较的已知结果去比较幂平均值、Stolarsky平均值和Heron平均值,简化了某些结果的证明,并得到了一些新的结果.     

A rate of approach to the steady state of solutions of second-order hyperbolic equations

In this paper projection methods based on expansions of solutions of retarded function differential equations in terms of generalized eigenfunctions are considered. It is first shown that the projection series developed earlier by Hale and Shimanov and those considered by Bellman and Cooke are actually the same. Using extensions of the residue-type arguments of Bellman and Cooke, convergence results are then established for a class of perturbed systems. These results are applied to obtain approximations to optimal controls for certain infinite dimensional variational problems. Numerical results are presented for several examples.