位置控制器与通用变频器APC系统

在每一周期的开始时的速度值V1预设定到传动装置上进行速度预控制，同时，反馈回来的实际值Sj与S1进行比较计算，得出当时偏差值△S，此偏差值△S乘以比例系数Ksp，得到Vk叠加在Vt上，得出传动装置应具有的速度控制信号V，然后V经速度／电压变换和D／A转换向传动系统的速度控制发出控制信号Uα控制执行机构的定位。调节Ksp的值使系统无超调无振荡。     

Overview of Existing Lunar Base Structural Concepts

Various structural concepts for lunar bases have been proposed and considered during the past three decades, each balancing the multitude of lunar constraints and anticipated base functions with a different distribution of weighting factors. This paper provides a brief review of the study of lunar base structures as well as an overview of current ideas. Lunar environmental characteristics are highlighted, and questions of structural functionality are categorized. In an appendix to the overview report, building systems proposed for lunar applications are categorized according to applications, application requirements, types of structures, material considerations, structures technology drivers, and requirement definitions. Another appendix presents a short list of the most important references related to these issues, as ranked by the task committee. This document contains a brief overview rather than an exhaustive review of concepts proposed for lunar outposts. The original documents, including those cited as references, are not replaced by this paper. However, this review is intended to be reasonably complete. There has been no conscious intention to ignore any work in this area of extensive ongoing activity.     

对海超视距导弹攻击方法分析

在对六种超视距目标定位法进行了评估与分析后，着重论述了对海超视距导弹攻击中目标定位的战术态热要求、导弹的射击阵位、导弹射击通道的组织与射击方式的选择，最后对超视距志弹攻击中存在的问题及提高导弹攻击效果的措施进行了论述。     

机械设备监测与诊断技术综述

机械设备监测与诊断技术,在设备维修领域中发挥着越来越重要的作用。其中,应用最广泛的是振动分析技术。     

NUMERICAL STUDY ON 3-D FLUID FLOW WITHIN THE MOLTEN POOL DURING UNEQUAL DIAMETER TWIN ROLL STRIP CAST-ROLLING

1.IntroductionNearNetShapeContinuousCasting(NNSCC)isoneofthemootadvancedteclmologiesinMaterialandMetallurgyinthe1990s.Meanwhile,thetechniqueoftWinrollStripCast--ROllingco~sfirst.Stripcast-rollingwhichcastsmoltenst.eeldirectlyilltostrip,eliminatingtheintermediatehot-stripmilloperation,hasformany}rearsbeenacherisheddreamofsteelengineerssincetheintreniionsofSirHenryBesseme.[1],Withtheplogressofsteelmakinganditsperipheraltechnologies,homelier,thedreanlisbeillgreallied.AsshowninPig.1,unequ…     

煤层气中甲烷δ~3C值偏轻的机理探讨

文中列出了５１个典型煤层气样品的甲烷δ１３Ｃ值测试数据，系统地分析了煤层气甲烷稳定碳同位素组成特征，深入探讨了甲烷δ１３Ｃ值偏轻的原因。     

冷轧扭钢筋在工程中的应用

本文主要介绍了冷轧扭钢筋的原理、特点、制作、材料成品检验及其有关规定。     

1991年我国工程塑料进展

根据国内有关工程塑料的文献,报道1991年国内热塑性树脂及塑料、热固性树脂及塑料、成型加工技术的进展,以及工程塑料在国民经济各个领域中的研究开发和应用。     

电镀制备铟-锡合金电极及其电还原二氧化碳性能

以腐蚀铜网为基体,在硫酸盐镀液中制备得到用于电还原CO2的铟-锡合金电极。对镀液配方进行了筛选,并通过正交试验对镀液配方进行优化,得到制备铟-锡合金电极的最佳工艺条件为:In2(SO4)350g/L,SnSO430g/L,柠檬酸40g/L,添加剂TSNA4g/L,稳定剂3g/L,电流密度1.5A/dm2,温度25°C,pH约1.5。最佳工艺下制备的In-Sn合金镀层呈均匀的灰白色,结合力良好,In-Sn合金电极上电还原CO2生成甲酸的电流效率达71%,稳定性良好。     

大庆石化公司聚烯烃树脂生产现状及发展

介绍了大庆石化公司现有聚烯烃装置的生产状况及聚烯烃新产品的开发．并从工艺角度与国内外同类装置进行了分析对比。最后简要介绍了大庆石化公司未来聚烯烃项目的发展规划。