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591.
592.
本文以北华航天工业学院图书馆的电子显示屏的使用为例,介绍了高校图书馆电子显示屏通过一定的控制方式显示文字、图形、二维或三维动画、电视等各种信息的方法,实现文本、图像、视频等多种内容形式的播放,彰显出电子显示屏在图书馆对外宣传服务中的优越性。 相似文献
593.
Quaternion regularization and trajectory motion control in celestial mechanics and astrodynamics: II
Yu. N. Chelnokov 《Cosmic Research》2014,52(4):304-317
Problems of regularization in celestial mechanics and astrodynamics are considered, and basic regular quaternion models for celestial mechanics and astrodynamics are presented. It is shown that the effectiveness of analytical studies and numerical solutions to boundary value problems of controlling the trajectory motion of spacecraft can be improved by using quaternion models of astrodynamics. In this second part of the paper, specific singularity-type features (division by zero) are considered. They result from using classical equations in angular variables (particularly in Euler variables) in celestial mechanics and astrodynamics and can be eliminated by using Euler (Rodrigues-Hamilton) parameters and Hamilton quaternions. Basic regular (in the above sense) quaternion models of celestial mechanics and astrodynamics are considered; these include equations of trajectory motion written in nonholonomic, orbital, and ideal moving trihedrals whose rotational motions are described by Euler parameters and quaternions of turn; and quaternion equations of instantaneous orbit orientation of a celestial body (spacecraft). New quaternion regular equations are derived for the perturbed three-dimensional two-body problem (spacecraft trajectory motion). These equations are constructed using ideal rectangular Hansen coordinates and quaternion variables, and they have additional advantages over those known for regular Kustaanheimo-Stiefel equations. 相似文献
594.
在制品管理中条码技术的应用 总被引:2,自引:0,他引:2
针对面向订单的单件、小批量生产制造企业,设计了一套条码数据采集系统,分析了主要运作流程和功能模块.在在制品的管理中提出了基于不同级别的工件生产状态定义,并给出了相应的加工、检验判定准则.经实际使用证明条码技术运用于工业现场是可行的. 相似文献
595.
Yu. P. Kataev 《Russian Aeronautics (Iz VUZ)》2012,55(2):192-195
In this paper, a proper choice of technological parameters for a shot peening process is considered, namely, the shot diameter, shot blast velocity, density of shot material, and depth of a plastically deformed layer-depending on the material being processed. The data presented can be used in calculations of technological parameters of FV monolithic panel shaping. 相似文献
596.
The results of a preliminary analysis of microperturbations on the International Space Station during physical exercises of the crew are presented. The goal of this paper is to identify the parameters of perturbations
when physical exercises are performed. The results of measurements by sensors of microaccelerations of both Russian and American
segments during physical exercises in the service module of the Russian segment are analyzed. 相似文献
597.
A. V. Tavrov O. I. Korablev A. V. Rodin I. I. Vinogradov A. Yu. Trokhimovsky A. Yu. Ivanov L. V. Ksanfomaliti D. A. Orlov 《Cosmic Research》2011,49(2):99-109
In order to observe exoplanets we propose a space-based achromatic stellar coronagraph combined with a 0.8–1.5 m telescope.
We develop an achromatic common path interferometer for observing an exoplanet (a faint off-axis source) on the background
of a hoste star (bright axial source). An image of the star and its copy acquire an achromatic phase shift by 180° and interfere
in antiphase. The achromatic phase shift is caused by geometric phase in the scheme of a three-dimensional interferometer.
The interference process divides spatially the dark and light fields of the star image redirecting them to the opposite sides
of a beam splitter. The interference process does not weaken the image of a planet, with equal intensities it is redirected
to both sides of a beam splitter. The suggested scheme of common path interferometer ensures mechanical stability. The background
signal is experimentally demonstrated to be reduced by six orders of magnitude. 相似文献
598.
王宇 《郑州航空工业管理学院学报(管理科学版)》2008,26(5):103-108
通过金融深化增加农村家庭参与金融市场的机会,提高农村家庭的福利,让金融为广大农村家庭服务,改善其资源配置,解决农村金融抑制的问题,是当前金融改革与发展的一个重要内容。文章将农村家庭的实物资产分为生活型与生产投资型,将金融资产分为安全型和风险型,根据问卷调查获取的数据建立Logistic回归模型,对东部地区农村家庭实物资产配置和参与金融市场的决定因素进行研究,探讨当前农村的金融深化与金融发展路径。 相似文献
599.
介绍一种以线性调频半导体激光为光源的衍射光栅干涉仪。激光与光栅上衍射的±1级衍射波会合,由于有光程差而发生光拍频,测量拍频信号的相位移则可测得光栅的位移。设计了一种克服激光波长漂移和空气折射率变化影响的对称差动光路,使这种方法达到实用化的程度,分辨力达到纳米级。此外,还介绍了应用于接触干涉仪的实验情况。 相似文献
600.
H. Fuke J.E. Koglin T. Yoshida T. Aramaki W.W. Craig L. Fabris F. Gahbauer C.J. Hailey F.J. Jou N. Madden K. Mori H.T. Yu K.P. Ziock 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(12):2056-2060
We discuss current progress and future plans for the general antiparticle spectrometer experiment (GAPS). GAPS detects antideuterons through the X-rays and pions emitted during the deexcitation of exotic atoms formed when the antideuterons are slowed down and stopped in targets. GAPS provides an exceptionally sensitive means to detect cosmic-ray antideuterons. Cosmic-ray antideuterons can provide indirect evidence for the existence of dark matter in such form as neutralinos or Kaluza–Klein particles. We describe results of accelerator testing of GAPS prototypes, tentative design concepts for a flight GAPS detector, and near-term plans for flying a GAPS prototype on a balloon. 相似文献