石油化工装备“后果分析”方法的介绍

石油化工装备的失效,由于所处理的物料常常是易燃易爆的化学品,所以往往导致发生燃烧、爆炸等,还可以波及附近的其它装置和设备发生连锁的失效和爆炸。为了分析这种严重事故可能造成的影响,研究防止这种事故的发生,近年来研究和发展了一种定量估计这种失效后果严重程度的方法,称为后果分析(Consequence Analysis)。通过分析,从这些设备的失效概率、可能发生的失效形式,研究设备内物料的泄漏形式、可能发生的后果、影响范围的大小、对周围装置、环境和人员的危害程度等,从而提出在设备设计、工厂的总图设计中采取的措施,以减轻其危害的程度。     

模糊神经网络控制器在飞行器姿态控制中的应用

基于ＡＫａｗａｍｕｒａ等人提出的Ｎｅｕｒａｌ－Ｆｕｚｙ协作系统概念［１］，根据模糊系统的结构，确定等价结构的神经网络。网络保留了模糊控制系统的优点，空间结构清晰，同时具有学习功能，并介绍了采用多层神经网络表达模糊控制系统的知识规则、模糊推理和学习算法，给出了控制某导弹纵向姿态的仿真结果，结果表明该控制系统具有较强的鲁棒性。     

运载器饱和非线性姿态控制系统稳定性分析

简要介绍了用描述函数分析饱和非线性系统稳定性的方法，然后在此基础上给出了适合于工程的饱和非线性系统稳定裕度的定义，研究了舵偏角不满足近似关系时，正弦函数非线性对姿控系统稳定性的影响，最后计算了某运载器的伺服机构处于饱和状态时姿态控制系统的稳定裕度。     

实时微分控制的算法研究

实时微分控制是进行航天器轨道控制的主要方法。本文在费景高所提出的算法基础上 ,提出了一种有效的改进算法 ,扩大了算法的适用范围。文章对算法的稳定性进行了研究 ,并给出了此算法在弹道导弹显式制导中的应用实例。     

0.8m 风洞风扇系统的设计和运转

为提高低速风洞的最大风速,根本的措施是设计高转速大功率的风扇系统。风扇系统的设计首先在于有一个良好的设计方法,选择高升阻比的风扇翼型,根据需要恰当地确定设计工况点,合理选择桨叶和反扭导流片的各个参数,如桨毂比、实度、升力系数和圆弧角等。设计中针对已经设计的外形,进行性能计算,可以迅速鉴别设计的优劣,检查是否能满足设计要求,节约研制成本和缩短周期。     

A strategy for investigation of the outer solar system

The requirements of systematic exploration of the outer solar system have been intensively studied by a Science Advisory Group (SAG) of consulting scientists for the National Aeronautics and Space Administration (NASA). Comets and Asteroids were excluded from this study, as a separate group is planning missions to these bodies. This paper and accompanying articles on specific related scientific subjects written by members of the SAG, summarize the findings and recommendations of this group. These recommendations should not be interpreted as official NASA policy. Following some general introductory remarks, a brief sketch is given of the development and current status of scientific missions to the inner planets by the U.S. and the U.S.S.R. With this perspective, the development of the U.S. program for investigation of the outer solar system is described. The scientific focus of outer solar system exploration has been studied in detail. The relationship of the outer planetary bodies to one another and to the inner planets, as parts in a unified solar system evolved from a primitive solar nebula, is emphasized. Deductions from outer solar system investigations regarding the conditions of the solar nebula at the time of planetary formation have been considered. Investigations have been proposed that are relevant to studies of the atmospheric structure and dynamics, internal structure of the planets, satellite composition and morphology, and planetary and interplanetary fields and energetic particles. The mission type and sequence required to conduct a systematic exploration of the outer solar system has been developed. Technological rationales for the suggested missions are discussed in general terms. The existing NASA program for outer solar system exploration is comprised of four missions:

1. Pioneer 10 fly-by mission to Jupiter and beyond, currently underway, with launch on 3 March 1972;
2. Pioneer G, intended for a similar mission with planned launch 2–22 April 1973; and
3. Two Mariner Jupiter/Saturn fly-bys in 1977, with experiment selection scheduled for late 1972 and detailed engineering design during 1972–74.

The Science Advisory Group advocates that detailed mission planning be undertaken on the following additional missions for launches during the late 1970's and early 1980's. Together with existing plans, these would provide a balanced, effective exploration program.

1. 1976 Pioneer Jupiter/Out-of-Ecliptic (One Mission)
2. 1979 Mariner Jupiter/Uranus Fly-bys (Two Missions)
3. 1979 Pioneer Entry Probe to Saturn 1980 Pioneer Entry Probe to Uranus via Saturn Fly-by (Three Missions)
4. 1981/1982 Mariner Jupiter Orbiter (Two Missions).

     

ISO 9000 认证所带来的利益及质量管理之发展(英文)

本文总结了９项有关ＩＳＯ９０００认证的研究，主要论述了这套国际标准为实施者所带来之利益。这９项研究分别在英国、新西兰、澳大利亚、中国香港特区、美国、巴西、加拿大、法国、德国、日本、韩国、瑞典和荷兰等地进行。研究发现，ＩＳＯ９０００的主要优点有：令运作方式系统化、减少损耗、增加效率和减少顾客投诉。取得ＩＳＯ９０００认证的公司，大多采取较严格的方法去控制分供方。不少取得证书的公司还表示，他们会进一步采用其他的质量管理方法，例如全面优质管理，ＩＳＯ９０００，ＩＳＯ１４０００和优质奖的规格。     

Lateral Flight Technical Error Estimation Model for Performance Based Navigation

Flight technical error (FTE) combined with navigation system error (NSE) is the main part of total system error (TSE) in performance based navigation (PBN).The implementation of PBN requires pre-flight prediction and en-route short-term dynamical prediction of the TSE.Once the sum of predicted lateral FTE and NSE is greater than the specified PBN value,the PBN cannot operate.Thus,accurate modeling and thorough analysis of lateral FTE are indispensible.Multiple-input multiple-output (MIMO) lateral track control system of a transport aircraft is designed using linear quadratic Gaussian and loop transfer recovery (LQG/LTR) method,and the lateral FTE of a turbulence disturbed approach operation is analyzed.The error estimation mapping function of latera FTE and its bound estimation algorithm are proposed based on singular value theory.According to the forming mechanism of lateral FTE,the algorithm considers environmental turbulence fluctuation disturbance,aircraft dynamics and control system parameters.Real-data-based Monte-Carlo simulation validates the theoretical analysis of FTE.It also shows that FTE is mainly caused by turbulence fluctuation disturbance when automatic flight control system (AFCS) is engaged and would increase with escalating environmental turbulence intensity.