A system of metrological assurance of measurement quality for the determination of chemical composition of light alloys and superalloys

 The paper covers the main principles of setting up and the function of the Russian system of metrological assurance of analytical measurements for the production of light alloys and superalloys. Received: 20 October 1998 / Accepted: 9 November 1998     

模糊分析计算中的结构元方法

提出模糊结构元的概念，研究模糊结构元的性质，给出模糊数和模糊值函数的结构元表现定理。利用模糊数和模糊值函数的结构元表现形式，使得过去必须依赖扩张原理和表现定理来刻画的模糊数运算、模糊值函数的微积分运算等变得更加简单与直观。     

The ‘Temperature Integral’ — Its use and abuse

This paper first reviews the history of the temperature dependence of reaction rate in reaction kinetics. The various equations which are in use today for expressing this dependence were delineated by van't Hoff almost one hundred years ago. Since an exponential form best describes this dependence for most thermal analysis reactions and, due to the fact that the simple Arrhenius equation (with a temperature-independent preexponential factor) has traditionally been used for this purpose, the mathematically intractable temperature integral often has become a necessary evil in the analysis of thermal analysis kinetics. Methods which avoid the temperature integral in kinetics analysis are discussed. The merits of various evaluations and approximations for the temperature integral are described and assessed in this paper.     

平衡随机模型中方差分量的非负估计

众所周知, 对于平衡随机模型, 方差分量的方差分析估计为一致最小方差无偏估计. 本文基于方差分量的方差分析估计, 构造了一个二次不变估计类, 它包含了一些常用重要估计. 证明了该估计类在一定条件下在均方误差意义下一致优于方差分析估计, 并在此估计类基础上, 给出了方差分量的两种非负估计, 它们在均方误差意义下分别一致优于方差分析估计和限制极大似然估计, 且有显式解、容易计算.     

基于模糊因素的载人航天器乘员舱内人-机界面工效学评价研究

载人航天器乘员舱内人－机界面的工效学评价是决定能否进行载人空间飞行的重要依据之一，由于人－机界面本身的复杂性，使得对其评价有一定的难度。本文在模糊理论的基础上，首先对舱内人－机界面工效学评价各参数进行随机模糊分析，据此建立工效学模糊综合评价模型，最后进行了实例研究。结果表明，对于同一个评价对象，应用该方法更能接近实际。     

原子吸收法在有机分析中的应用（Ⅴ）─甘草及其制品中甘草酸分析法的研究

原子吸收法在有机分析中的应用（Ⅴ）─甘草及其制品中甘草酸分析法的研究郎惠云，谢志海，赵怡（西北大学化学系西安，７１００６９）关键词原子吸收法，有机分析，甘草酸现代医药研究证明，甘草草药理作用的活性成分为甘草甜素或甘草酸，其定量测定方法国内外虽有报导￣...     

Ultrasound-assisted extraction and analysis of maidenhairtree polysaccharides

The maidenhairtree polysaccharides (MTPs) have important application prospects. So, the extraction, purification, structure, derivatization and biological activities of polysaccharides from leaves, fruits, and testae of maidenhairtree were disscussed. Polysaccharides were extracted by collaborative extraction methods such as ultrasound-assisted extraction and microwave-assisted extraction. The ultrasound-assisted extraction had higher content and higher efficiency. The structural characteristics and structure-activity relationship of maidenhairtree polysaccharides were studied in order to provide theoretical basis and technical support for the further development and utilization of maidenhairtree polysaccharides.     

地质灾害图形图象分析系统在天津地面沉降分析中的应用

地质灾害的分布和发生发展过程具有空间特性, 其影响因素具有自身的特点和复杂性。作者开发的地质灾害图象分析系统(GHMIAS)是以典型地质灾害为主要对象、以空间信息管理和分析为主要功能的应用性地理信息系统, 该系统有独特的空间分析模型扩充, 融矢量、栅格和Windows图形用户对象为一体, 支持多种数据格式相互转换, 具有丰富的制图功能和高质量的制图输出, 可以快速生成灾害专题图件。     

极限分析的无搜索数学规划算法

本文研究理想刚塑性介质极限载荷因子的计算方法。根据极限分权理论的上限定理,建立了计算极限载荷因子的一般数学规划有限元格式。针对这种格式的特点,提出了一个求解极限载荷因子的无搜索迭代算法。这个算法中采用逐步识别刚性、塑性分区,不断修正目标函数的方案,克服了目标函数非光滑所导致的困难。本文提出的算法建立于位移模式有限元基础上,有较广的适用范围,且具有计算效率高,稳定性好,格式简单易于程序实现等优点。