可理解的语言输入(CI) 在英语教学中的意义

本文介绍了Krashen的CI研究,并从实际教学角度探讨了CI在英语教学中的意义,主要包括语言教材的选取、语言教材的表现手段、语言教材的数量、情感过滤等方面。     

模同态的延拓

本文讨论了模上同态延拓的条件，并给出延拓唯一的条件。     

Analysis of Policy Factors in the Stock Market

One model of stochastic time series - Markov chain was presented in this paper. We study and discuss the application of this model. Some results that the policy factor make to stock price were offered when this model is applied to analyze the index of Shanghai stock market quantitatively.     

Application of the Season Time Series Model to Forecast the Rainfall in the Area of Well Irrigation Rice in the Sanjiang Plain

The area of well irrigation rice became more and more, so the crisis of groundwater appeared. Making the most of rainfall is an availability method in water saving irrigation, increasing water temperature and raising yield. Just based on this, through applying the theory of season random time series, according to the data of average monthly rainfall (1981 - 1999), the authors build up the forecasting model in the area of well irrigation rice in the Sanjiang Plain. Through contrasting with practical value, the model has good effect.So, it can be used in water irrigation management.     

约束可满足问题求解策略的改进和实验结果

通过对那些属于ＮＰ－Ｃｏｍｐｌｅｔｅ的约束可满足问题（如图着色，规划、ＳＡＴ问题等）的求解实验，指出了局部搜索算法的局限性，由此给出改进的搜索策略，实验结果表明，应用改进的搜索策略使算法效率明显提高。     

关于有限BCI—代数的拟可换性

本文主要对胡庆平在BCI—代数一书中提出的问题“有限的BCI—代数是否一定是拟可换的”给出了肯定的回答,同时还得到BCI—代数定义中公理V可以由前边四条公理推出。     

几类一阶非线性微分方程的解

本考虑了3种类型一阶非线性微分方程的可积性，并给出了通解。     

可达性等价于状态方程可满足性的两个Petri-Nets子类

可达性是Petri网的一个基本性质,其判定问题是Petri网理论研究方面的一个重要课题.众所周知,一个Petri网的状态方程可满足性是其可达性的一个必要不充分条件.然而[2]证明了,对于活的T-系统,其状态方程可满足性是其可达性的一个充分必要条件.另外[3]指出,对于活的加权T-系统,这一点也成立.下面第1部分给出一种包含活T-系统的活Petri网子类,并证明其状态方程可满足性是其可达性的一个充分必要条件.特别地,第2部分提出另一种Petri网子类(可以是不活的),并证明其状态方程可满足性也是其可达性的一个充分必要条件.