数值积分的padé逼近方法

本文将Pade′逼近方法应用于定积分的数值计算。讨论了收敛性,给出了若干近似计算公式。当应用这些公式计算某些定积分时,得到了较为精确的结果。     

组合夹具CAD中子组装模块参数化设计的研究

本文提出了组合夹具CAD子组装模块的概念,进行了参数化设计的探讨。文中重点叙述了参数化设计的方法及其优越性,并对设计中的具体问题,如夹具元件的确定,参数的输入、模块的生成等,做了深入的介绍。     

含氟硫A矿的水化特性

研究了含氟硫Ａ矿的水化性能及Ｆ－、ＳＯ３和Ａｌ３＋固溶量变化对Ａ矿性能的影响。研究结果表明，含氟硫Ａ矿早期水化率、液相ｐＨ值和Ｃａ（ＯＨ）２过饱和度均较大，水化产物细化，强度提高，但凝结时间较长。Ａ矿固溶Ｆ－增多．凝结时间延长；固溶Ａｌ３＋可提高水化活性；固溶ＳＯ３可缩短终凝时间。实验结果还证明，石膏可显著加快Ａ矿的早期水化。     

可微函数鞍点识别的条件

列举了Ｗｉｓｍｅｒ等人所给的鞍点识别充分条件的反例，并给出了正确的鞍点识别条件。     

横向裂纹损伤扩展特性分析

文章对典型铺设的［０２／±４５２／９０２］ｓ碳／环氧复合材料层板中的典型损伤状态进行了实验观测，建立了横向裂纹扩展的三维有限元分析模型。结果表明，横向裂纹是层板的主要损伤型式，横向裂纹的出现能够改变无损伤状态时层板的层间应力分布状态，对分层出现的位置起决定性影响。     

Windows环境下光伏水泵报价系统的实现

该文介绍了在Ｗｉｎｄｏｗｅ３．１环境下．利用ＭｉｃｒｏｓｏｆｔＣ（＋＋）及其基本类库（ＭＦＣ）开发光伏水泵报价系统的方法。该方法采用了面向对象技术，使软件具备可重用性。同时，ＭＦＣ类库的使用使复杂的Ｗｉｎ－ｄｏｗｓ应用程序的编程接口变得更容易。该方法对其它工程报价问题也具借鉴意义。     

无绳集团电话双音多频DTMF信号的实现

介绍了在无绳集团电话研制中所采用的双音多频ＤＴＭＦ信号的一种实现方法，通过软件模拟不同的单音频率，并对其按一定的采样速率取样，叠加即得到相应的双音多频ＤＴＭＦ信号。同时讨论了帝现的原理及软、硬件设计，并对结果进行了分析。     

广州市偏头痛调查及初步分析

本文首次报导1983年在广州地区调查的偏头痛流行病学资料。本区偏头痛发病率为13.1/10万。患病率为306/10万。14岁以下,尚未记录到有患者。广州地区偏头痛发病率和患病率明显低于国内六大城市以及国外资料。女性患者为男性的三倍,此一比例高于国外报导。家族偏头痛史及个人过敏史有一定意义。     

Tilman's predicted productivity-diversity relationship shown by desert rodents

Tilman has developed a model to predict the number of plant species that can coexist competitively on a limited resource base. Species diversity first increases over low resource supplies, then declines as the environment becomes richer. Although Tilman 's model was developed to describe interspecific interactions between plant species, it may also apply to animal species. Tilman questions whether animals specialize on particular proportions of nutrients. However, we believe animals probably specialize on relatively subtle microhabitat differences, especially in a multispecies competitive regime. Thus, microhabitats may act like nutrients. We hypothesize that animal species, too, show a peaked curve of diversity over productivity. The present data provide a confirmation of the hypothesis using rodent species. We have investigated the number of rodent species along a geographical gradient of increasing rainfall. The gradient extends from extremely poor desert habitats to those with annual rainfall over 300 mm. Because of the aridity , precipitation reflects productivity. The diversity pattern in desert rodents agrees with that predicted by Tilman for plants. It even possesses similar asymmetry, rising steeply then falling slowly. The pattern is duplicated in rocky and sandy habitats, each of which has a distinct and almost nonoverlapping assemblage of species. As mean precipitation is closely correlated with the variability of precipitation, the diversity pattern might also be caused by a decline in the frequency of disturbances, models for which have been proposed by several investigators.     

梳毛机的梳理机理和梳理程度 理论部分

首先分析了工作辊和道夫对毛纤维的梳理机理，建立了梳理模型。在考察了纤维转移和负荷重新分配过程中纤维受到的梳理齿数的基础上，提出了梳理程度的表达方法和表达式。同时建立了罗拉梳理机特有的循环梳理负荷和循环梳理齿数的新概念。