MIS信息需求分析方法的比较研究

论述了3种MIS信息需求分析方法即决策分析法、数据分析法和原型法的差异,对于不同的资源需求、过程特征、输出信息特征、用户的理解力和系统分析员的理解力,信息系统需求的分析应采用不同的方法。讨论结果表明,原型法是最佳方法,其次是数据分析法,最后是决策分析法,系统分析人员可以采用多种方法的组合,以弥补各种方法的不足。     

Error analysis and distribution of the driving mechanism for large spherical radio telescope active reflector

In order to reduce the cost, 3-PRS mechanism is introduced into the application of supporting the active reflector unit of large radio telescope. The kinematic model of 3-PRS mechanism with rotational joint errors is derived to solve the error problem in actual engineering application. Then based on the error model, inverse and forward kinematics are analyzed. Because the solutions can not be analytically expressed, a numerical method is applied. Afterwards, the parasitic motion errors are analyzed using search method and empirical formulas of the maximum parasitic motion error are put forward. Finally, the tolerance is distributed using empirical formulas to avoid interference between adjacent reflector units. The analyses provide a theoretical basis for the design and installation of large radio telescope active reflector.     

混杂纤维混凝土动力特性的试验研究

混杂纤维混凝土是高性能混凝土的一种重要形式,本文研究探索了钢纤维与粗合成纤维混杂构成的纤维混凝土的动力特性,并基于试验结果,分析了混杂纤维的增强机理。结果表明：混杂纤维混凝土的初裂、破坏冲击次数及冲击韧性比单一纤维混凝土分别提高了0．2～0．4、1．0～4．0和1．0～2．0倍,表明两种纤维具有良好的协同效应,同时,数理统计分析方法可以较客观、全面地反映混杂纤维混凝土的动力特性。     

企业购并的信息需求模型分析

构建企业购并活动的信息需求模型,以此为企业的决策者在资本运营活动中提供帮助是很有意义的.在本文中作者提出了企业购并信息需求模型的架构,并对主要的辅助信息需求进行了分析,提出了相应的处理方法.     

高级机构运动分析CAD系统的研制与开发

根据角变量逼近法对高级机构进行了运动分析，研制了高级机构运动分析CAD系统，介绍了开发平台和主界面，讨论了程序开发的一些技术处理．给出了全R副Ⅱ级杆组运动分析流程图和通用模块的核心步骤，并以编织机为倒说明了软件的使用．     

0.6准则在抗震计算中的应用

抗震计算中一般只取前s阶振型，误差较大，为此研究如何取s及其计算误差显得尤为重要。应用结构动力计算的0．6准则解决这个问题，可达到取s少、计算简便的目的，并使误差分析较准确。     

中学生体育学习成败归因研究

中学生体育学习的成功和失败归于何种原因?本以韦纳的成就归因4因素论为理论依据，通过《中学生体育学习成败归因问卷》(自编)进行调查．运用主成分分析法，对调查结果进行统计运算，构建了成功归因4因素和失败归因5因素的原因结构，并分别对成败归因进行差异检验，提出了3项教学建议．     

峨眉山绿豆岩的应用及其成因探索

该文对峨眉山龙门洞三叠系中统雷口坡组底部“绿豆岩”运用多种分析手段,了解绿豆岩的物质成分及其在农业上的应用。并结合野外观察,对其形成环境及成因进行初步探索。     

Genetic and morphometric variation in the potamonautid river crab Potamonautes parvispina (Decapoda: Potamonautidae) from two Western Cape rivers,South Africa

Patterns of genetic and morphometric variation amongst five populations of Potamonautes parvispina from two rivers in the Western Cape, were examined. Genetic variation at 14 loci was investigated using protein gel electrophoresis. The results showed that the populations were genetically invariant within and between the two drainage systems. Discriminant functions analyses of seven carapace variables demonstrated regional differentiation between the population groups in the two drainage systems. Other morphometric characters exhibited a significant degree of variation within drainage systems. Morphometric data were highly variable and were discordant with the genetic data, which suggests that environmental factors may be responsible for the large degree of phenotypic plasticity. Results from the present study are discussed in terms of widespread gene flow and recent population divergence.     

地层沉陷的数值模拟应用研究

系统地总结了近些年来，应用有限元、离散元等数值分析方法研究开采引起地层沉限的一些成果，用有限单元法分析了辽源矿务局西安煤矿立井保护煤柱开采引起的筒变形和滑移，在断层与井筒交界处，井筒发生了错动，且周围明显呈现塑性破坏区；用离散单元法研究了地下开采引起地层沉陷的动态发展过程，对指导建（构）筑物下开采具有重要意义，并且表明数值模拟方法对分析含构造岩林地表沉陷是行之有效的。