第三类边界条件下球内凝固问题的摄动解

对第三类边界条件下，初态在熔点的球内相变介质的凝固问题，采用一种奇异摄动方法求解，以Ｓｔｅ数作摄动参数，将温度、移动界面位置以及球坐标按摄动参数展开，得到一个附近似解，并分析讨论了Ｂｉ数和Ｓｔｅ数对凝固过程的影响。     

关于一类半线性椭圆型方程的爆破解

提供一种新的方法研究问题（１）解的存在性，在此对ｋ（ｘ）的限制要比已有文献弱。     

正交组的初等变换求法

本文给出了用矩阵的初等变换求正交组的一种方法.     

谈Joshi水平井产量公式

认为 Joshi在推导水平井的产量公式时 ,把水平井的流动视做向一个点汇的垂直流动与向一与水平井等长的垂直裂缝的水平流动的代数相加 ,这种简化处理是不对的 ,物理解释是牵强的 ,所给的水平井产量公式是错误的 .文中在保证地层内具有稳定流动的基础上 ,利用保角变换对顶底不渗透油藏中心有一口水平井的产量公式进行了重新推导 ,给出了水平井产量公式的修正公式 ,并且利用等值渗流阻力法进行了解释     

煤气站凉水塔的技术改造

通过对冷煤气站中凉水塔的重要作用及其现状、运行形式的介绍，提出了存在问题及改造方向，并认为WTZ系列玻璃钢风筒式自然吸风凉水塔可作为今后煤气站凉水塔改造的首选方案。     

化归方法在数学分析中的应用

从方法论角度阐述了数学化归法在数学分析中的应用和意义.     

Robust stability test for 2-D continuous-discrete systems with interval parameters

It is revealed that the dynamic stability of 2-D recursive continuous-discrete systems with interval parameters involves the problem of robust Hurwitz-Schur stability of bivariate polynomials family. It is proved that the Hurwitz-Schur stability of the denominator polynomials of the systems is necessary and sufficient for the asymptotic stability of the 2-D hybrid systems. The 2-D hybrid transformation, i. e. 2-D Laplace-Z transformation, has been proposed to solve the stability analysis of the 2-D continuous-discrete systems, to get the 2-D hybrid transfer functions of the systems. The edge test for the Hurwitz-Schur stability of interval bivariate polynomials is introduced. The Hurwitz-Schur stability of the interval family of 2-D polynomials can be guaranteed by the stability of its finite edge polynomials of the family. An algorithm about the stability test of edge polynomials is given.     

HEAVY TRAFFIC LIMIT THEOREMS IN FLUID BUFFER MODELS

A fluid buffer model with Markov modulated input-output rates is considered.When traffic intensity is near its critical value, the system is known as in heavy traffic.It is shown that a suitably scaled sequence of the equilibrium buffer contents has a weakor distributional limit under heavy traffic conditions. This weak limit is a functional of adiffusion process determined by the Markov chain modulating the input and output rates.The first passage time of the reflected process is examined. It is shown that the mean firstpassage time can be obtained via a solution of a Dirichlet problem. Then the transitiondensity of the reflected process is derived by solving the Kolmogorov forward equation witha Neumann boundary condition. Furthermore, when the fast changing part of the generatorof the Markov chain is a constant matrix, the representation of the probability distributionof the reflected process is derived. Upper and lower bounds of the probability distributionare also obtained by means of asymptotic e     

Improved fuzzy identification method based on Hough transformation and fuzzy clustering

This paper presents an approach that is useful for the identification of a fuzzy model in SISO system. The initial values of cluster centers are identified by the Hough transformation, which considers the linearity and continuity of given input-output data, respectively. For the premise parts parameters identification, we use fuzzy-C-means clustering method. The consequent parameters are identified based on recursive least square. This method not only makes approximation more accurate, but also let computation be simpler and the procedure is realized more easily. Finally, it is shown that this method is useful for the identification of a fuzzy model by simulation.