Recurrent form of the least squares method in the problem of processing phase satellite navigation measurements

The fundamental difference of phase measurements from other measurements in satellite navigation is the presence of constant ambiguous component because of which the acceptable estimate quality is achieved only in the case of measurement during some time interval. In the framework of conventional relations of the least squares method, it is necessary to process matrices with large dimensions which have no pronounced banded or diagonal structure. A recurrent procedure equivalent to the least squares method in the considered problem is proposed; this procedure deals with matrices of small dimensions. The quantities characterizing the quality of the obtained estimate (precision dilution factors) are determined.     

基于网络的智能辅导模式研究与系统设计

针对目前辅导行业的现状,为解决课后辅导的自动化、实时化的问题,分析了学生课后学习掌握知识的过程,提出了一个基于学生课后学习规律的辅导模型,建立了面向问题的多层面知识辅导新模式,构建了基于此模式的网络智能家教系统的框架结构。该系统采用基于知识的自动推理技术使得推理过程得以完整保存来分析后续的多层面辅导信息,采用资源模型分解知识粒度保证抽象度,采用网络服务模式满足用户的实时使用。以学生提出的几何问题为实例,展示了多层面辅导过程,实验结果表明了该模式和系统设计的可行性。     

Use of TVD-schemes to simulate gasdynamic flows with spherical and cylindrical symmetry

A generalization of the Harten TVD-scheme in the form of a predictor-corrector-type scheme of second-order accuracy in time and space is proposed for the flows with spherical and cylindrical symmetry. The scheme does not require introducing components with artificial viscosity and describes discontinuities in the solution without the appearance of nonphysical oscillations for a Courant number less than 0.8.Academic Scientific Complex A. V. Luikov Heat and Mass Transfer Institute of the Academy of Sciences of Belarus, Minsk. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 65, No. 3, pp. 296–301, September, 1993.     

金寨县中小型水库除险加固需重视的问题

文章分析当前中小型水库运行常见险情,探讨了除险加固需重视的问题。     

对安徽省城镇体育人口与经济发展特征探析

运用文献资料、访谈、问卷调查、数理统计等研究方法,对安徽省城镇体育人口现状进行调查研究,结果显示:安徽省经济发展迅速,社会体育人口比率与城镇居民人均可支配收入成正比,与各地市人口总数成反比。安徽省城镇体育人口性别比为109.55,分别高出全国和安徽省人口性别比4.35和6.16。     

有限差分法计算HF分子的振动能级和光谱

本文用有限差分法计算了HF分子的振动能级并且把计算的结果用切比雪夫法进行拟合得到了HF的光谱项,将所得结果与黄整等人的用时域有限差分法计算所的结果和实验值进行了比较。     

基于VRML的虚拟实验室交互控制方法研究

介绍一种采用VRML开发的实现数字逻辑电路虚拟实验室交互控制的方法。首先从系统的整体体系结构出发，详细地论述了虚拟实验室交互控制的事件驱动原理，然后以芯片插入面包板为例，给出实现这一交互控制过程的具体方法。     

企业信息化规划评价的层次分析方法

在总结传统企业信息化评价内容、方法的基础上，着重介绍了定性与定量分析相结合的层次分析法(AHP)理论及信息实施顺序评价中的AHP建模方法，并运用AHP评价模型对某公司规划的信息化实施顺序进行了分析评价．为决策者进行信息化规划决策提供了科学依据。