基于光电自准直仪的静压长导轨设计及测量

为了实现对长导轨的直线度精密测量,完成了静压长导轨的设计,并采用光电自准直仪对长导轨精密加工中进行了测量、检验;进行了长导轨各段的三次实测数据和直线度计算,对同类工程测量具有一定的指导意义。     

Evaluation of Characteristics of Non-Metallic Inclusions in P/M Ni-Base Superalloy by Automatic Image Analysis

Non-metallic inclusions,especially the large ones,within P/M Ni-base superalloy have a major influence on fatigue characteristics,but are not directly measurable by routine inspection.In this paper,a method,automatic image analysis,is proposed for estimation of the content,size and amount of non-metallic inclusions in superalloy.The methodology for the practical application of this method is described and the factors affecting the precision of the estimation are discussed.In the experiment,the characteristics of the non-metallic inclusions in Ni-base P/M superalloy are analyzed.     

西文 DOS 环境软件设计的汉字界面技术及其应用

阐述了精密仪器软件在西文ＤＯＳ环境中运行的汉字界面模块功能和设计中的主要问题，介绍了该模块在精密轴系径向回转误差测量数据处理软件设计中的应用。     

空间拦截非线性控制问题的高精度计算

在空间拦截非线性控制问题数学模型的基础上，采用动力系统的一种高精度计算方法－时程精细分法，对非线性空间拦截问题进行了研究，其主要步骤为，首先将非线性控制问题线性化，使其满足精细积分算法的要求，进而根据线性化的方程，建立一套处理非线性问题的精细迭代算法，该算法不仅具有很高的计算精度，还具有很好的数值稳定一。     

现役装备维修性增长的投入精度控制

装备维修性由含有多个参数的指标体系决定,其增长方案的优选属于多属性优化决策的范畴.数据包络分析理论以客观评价多属性参评单元和固有包容性见长,将它应用于装备维修性增长投入方案优化,不仅能对现有各方案进行优劣排序,而且可通过建立前沿面,指出非最优方案样本的具体问题所在及其改进的方向和程度,使得改进后的维修性增长方案相对于样本方案系列为最优.进一步地,还可据此对未来决策单元的可行性和改进措施等给出判断和精确指导.     

大迎角气动导数对飞机横船向飞行品质的影响

以第三代战斗机为例，采用等效系统方法，通过计算并讨论飞行品质指标滚转模态时间常数（Ｔｒ），荷幸滚模态的阻尼比和频率及驾驶员座位处的加速度随气动导数的改变特征，研究在失束宛角前大迎角气动对具有现代控制系统的飞机横向飞行品质的影响。结果表明，气动导数Ｃｌδａ和ｌｐ主要影响Ｔｒ及ａｙｐ；Ｃｎδｒ，Ｃｎδｒ，Ｃｎｒ，Ｃｎβ及Ｃｙβ主要影响ξｎ或ωｎ；Ｃｌβ的影响相对较小。     

Properties of the high area-to-mass ratio space debris population at high altitudes

In the framework of its space debris research activities ESA established an optical survey program to study the space debris environment at high altitudes, in particular in the geostationary ring and in the geostationary transfer orbit region. The Astronomical Institute of the University of Bern (AIUB) performs these surveys on behalf of ESA using ESA’s 1-m telescope in Tenerife. Regular observations were started in 1999 and are continued during about 120–140 nights per year. Results from these surveys revealed a substantial amount of space debris at high altitudes in the size range from 0.1 to 1 m. Several space debris populations with different dynamical properties were identified in the geostationary ring. During the searches for debris in the geostationary transfer orbit region a new population of objects in unexpected orbits, where no potential progenitors exist, was found. The orbital periods of these objects are clustered around one revolution per day; the eccentricities, however, are scattered between 0 and 0.6. By following-up some of these objects using the ESA telescope and AIUB’s 1-m telescope in Zimmerwald, Switzerland, it was possible to study the properties of this new population. One spectacular finding from monitoring the orbits over time spans of days to months is the fact that these objects must have extreme area-to-mass ratios, which are by several orders of magnitudes higher than for ‘normal-type’ debris. This in turn supports the hypothesis that the new population actually is debris generated in or near the geostationary ring and which is in orbits with periodically varying eccentricity and inclination due to perturbations by solar radiation pressure. In order to further study the nature of these debris, multi-color and temporal photometry (light curves) were acquired with the Zimmerwald telescope. The light curves show strong variations over short time intervals, including signals typical for specular reflections. Some objects exhibit distinct periodic variations with periods ranging from 10 to several 100 s. All this is indicative for objects with complicated shapes and some highly reflective surfaces.     

New He neutron monitor for Chilean Cosmic-Ray Observatories from the Altiplanic zone to the Antarctic zone

We present the results of three years of continuous operations and the principal characteristics of our new ³He neutron monitors installed in the Chilean Network of Cosmic-Ray Observatories. During the years 2004 and 2005, we began the construction of this International Geophysical Year (IGY)-type ³He neutron monitor, with the intention of replacing the older proportional tubes of the BF₃. These new monitors are installed in stations at locations ranging from the near-equatorial zone to the Antarctic zone. As a reference system, we used our own BF₃ neutron monitors and previously complemented the collected data with a Monte Carlo simulation for the proton-yield function response of the Putre neutron monitor. Herein, we present for the first time the data obtained from our new high-mountain observatory located in the Altiplanic zone.     

牛顿流理论及其在谐振机翼上的应用

根据牛顿流理论,文中讨论了高马赫数、任意迎角、一般剖面在均匀来流中作沉浮和俯仰谐振的翼型和机翼。导得翼型和机翼表面的牛顿撞击压强和安定性导数公式。给出楔、平板三角翼、双抛物线剖面三角翼俯仰刚性导数(-C_(mθ)和阻尼导数(-C_(m))的数值例子。数值结果与现有的牛顿-布兹曼流理论、薄激波层理论、欧拉方程摄动理论的结果作了比较,算例表明本文的结果令人满意。     

微米级自动扫描磨粒形态分析仪运动系统的设计及制造

介绍了自动扫描磨粒形态分析仪运动系统的设计、关键技术的解决途径及制造过程中的关键工艺问题的研究成果．