大空域机动巡航导弹的模糊PID控制器设计

针对大空域机动巡航导弹下降转平飞过程中出现的强非线性特点．在俯仰通道设计了模糊PID双模控制方案。以高度误差和该误差变化量为输入．以高度误差为阀限．在高度误差较大时采用响应迅速的模糊控制器．较小时采用稳态精度较高的PID控制器。最后通过仿真表明通过该方案所控制的弹道符合方案弹道．满足设计指标要求。     

大伙房水库输水工程隧洞结构应力仿真分析

应用有限元法对辽宁省大伙房水库输水工程主体隧洞结构进行了仿真分析,从而得到隧洞结构的应力分布规律,研究确定薄弱部位并采取相应的稳定措施,以便保证隧洞施工的安全与经济。     

Efficient and accurate waveguide mode computation using BI‐RME and Lanczos methods

In this paper, a special purpose algorithm for solving large eigenvalue problems based on the Lanczos method is successfully applied to an engineering problem: the electromagnetic analysis and design of passive waveguide devices. For dealing with such complex problems, the boundary integral‐resonant mode expansion (BI‐RME) technique has been recently proposed. This technique solves integral equations (IEs) through the well‐known method of moments (MoM), thus leading to structured eigenvalue problems. These problems frequently become very large when solving complex arbitrary geometries with high accuracy. In such cases, the eigenvalue problem cannot be efficiently solved with standard methods by means of personal computers, essentially due to CPU time and memory allocation requirements. In this paper, we propose an alternative technique, based on the Lanczos method, for the fast and accurate solution of large BI‐RME generalized eigenvalue problems. The novel theoretical aspects of this approach, as well as the impacton the original BI‐RME formulation, are described. Comparative benchmarks are also successfully presented for the full‐wave analysis and design of real passive microwave devices. Copyright © 2005 John Wiley Sons, Ltd.     

用于大位移情形的杆系结构虚功原理

通过典型示例揭示了传统杆系结构虚功原理在“微小位移”假定下,忽略挠度的一阶导数,用二阶导数代替曲率,造成的近似计算的假象,以及引起的概念上的混乱. 论证了虚功原理实质上是一组精确的数学恒等式,只是通过定义“力”和“位移”使其中每一项都赋予了虚功的物理意义,并不存在近似的问题. 提出了用截面转角的正切值定义截面的转动位移,并将虚功中力和位移的关系描述为力不随位移拖动的模式. 由此澄清了传统虚功原理可能引起的“近似计算,只适用于小位移”的假象,使虚功原理可以抛弃小位移假定,精确地适用于大位移情形.     

自焙炭块在大型高炉上应用十年概况

自焙炭块陶瓷砌体复合炉缸技术在大型高炉上的应用已有10年，总的来说是成功的，但由于自焙炭块自身的特性，应用中也暴露出了一些问题。通过对国内大型高炉应用自焙炭块陶瓷砌体复合炉缸技术的全面调查，分析了该技术的应用前景，提出了改进措施。     

一种基于模式搜索的大尺寸测量移站坐标转换方法

针对空间大尺寸测量的移站坐标转换，提出了最小二乘坐标转换数学模型和基于模式搜索的参数求解方法，实验证明该方法具有理论正确性和实际可行性。     

催化裂化大油气管线阻焦剂的研究与开发

介绍了阻焦剂的阻聚分散机理，测定了不同组分的阻焦剂对不同性质原料的阻焦效果，并考察了不同加入浓度对阻焦率以及催化裂化产品分布的影响。试验结果表明：加入50—100μg/g的阻焦剂，可使催化裂化大油气管线阻焦率达到53．7％—63．8％，同时对产品分布及产品性质无不良影响，具有技术经济可行性。     

郑411块超稠油试油试采工艺技术应用

郑411块沙三段地层疏松出砂、原油粘度高，属中深层超稠油，常规试油试采方法难以突破出油关，采用APR全通径氮气垫测试、地层与井筒复合防砂、水平井配合直井蒸汽吞吐、氮气泡沫封堵调剖和井筒加热举升稠油等配套工艺技术，取得了较好的效果，为中深层超稠油油藏的开发提供了技术思路。     

Dynamic elastic-plastic behaviour of whipping pipes: experiments and theoretical model

This paper is concerned with the problem of pipe whip, the dynamic response of a high pressure piping system subjected to an end force as the result of a pipe break which releases a jet of fluid from the broken section. Both experimental and theoretical results are presented concerning the dynamic elastic-plastic behaviour of cantilever pipes subjected to a transverse force pulse at the free end. Comparisons between experimental data and theoretical predictions are made for mild-steel pipes with outer diameter-to-thickness ratios of 19.5, 28 and 32. It is demonstrated that, for these geometries, the whipping pipes display three characteristically different responses, viz. elastic, plastic hardening behaviour for thick pipes, elastic, plastic hardening-softening behaviour for moderately thick pipes and elastic, plastic hardening-softening-collapse behaviour for thinner pipes. The experimental data taken from a series of high-speed films are compared with the predictions of the instantaneous shapes of the whipping pipes derived from both a rigid, perfectly-plastic, large deflection, dynamic beam model and a more comprehensive model which incorporates the effects of elasticity and plastic hardening and softening, the details of which are presented in the paper.