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1.
《中国航天》2008,(4):37-38
英国维珍银河公司1月23日公布了其亚轨道太空旅游飞船及其载机的设计.根据设计,未来想找刺激的人将可以乘坐一种漂亮的飞船到太空边缘观光旅游.称为"太空船二号"的飞船将挂载在庞大的"白骑士二号"双体载机下部升空.  相似文献   

2.
叶轮盖板侧的流动对离心泵泄漏量的影响   总被引:2,自引:0,他引:2  
利用动量矩定理,建立了叶轮盖板中流体旋转角速度的一阶微分方程,得到了计算离心泵泄漏量的方法.为了获得泄漏量,需要进行迭代求解.从该微分方程出发,可得到容积效率、轴向力等参数.试验研究表明,用此公式计算的理论泄漏量和试验值之间的相对误差在7%~10%以内,验证了该方法的合理性和正确性.  相似文献   

3.
21世纪初,美国、俄罗斯、欧洲(含各国)、日本以及印度等国家或地区纷纷出台了一系列新的深空探测发展战略和相应的规划与计划.为了实现这些战略和计划,首要之举就是突破关键技术.目前各国正在为月球、火星和更远天体的科学探测任务研发各类关键技术.  相似文献   

4.
电子系统的电磁脉冲效应及防护   总被引:1,自引:0,他引:1  
侯民胜  问建 《航天电子对抗》2007,23(3):15-17,24
电磁脉冲对电子系统具有很强的干扰和破坏作用.为研究电磁脉冲对电子系统的影响,进行了静电放电电磁脉冲对单片机系统的辐照效应实验.实验表明,单片机系统在静电放电电磁脉冲作用下,会出现多种故障现象.在效应实验基础上,研究了单片机加固技术.  相似文献   

5.
作者根据多年的实践经验,对该文献中重要部分进行了点评,指出:空间系统的结构设计要"严格"按照环境设计来进行考核,而环境试验的目的除了筛选工艺质量之外,更重要的是验证设计载荷是否合理.文章还分别对声、振动和冲击试验中的关键步骤和内容进行了解析和说明.  相似文献   

6.
李旻  姚方競 《航天电子对抗》2007,23(6):12-13,64
阐述了星载信息安全保障系统对卫星自身信息安全防护的重要意义.介绍了星载信息安全保障系统的概念、基本组成,以及与卫星其它部分之间的关系.对该系统的信息感知、信息环境分析和行动决策、信息对抗三个子系统的基本功能和工作方式进行了描述.  相似文献   

7.
引言遂宁近距导航台为NDB导航台,始建于1980年5月,于1982年正式启用。该台站站址距遂宁机场跑道北端1025m,台站工作频率为465kHz,识别信号为M。于2002年8月26日因校飞时信号偏  相似文献   

8.
征稿简则     
《航天电子对抗》2008,24(1):64-64
  相似文献   

9.
(八)综合电子系统技术 综合电子系统将深空探测器的遥测、遥控、自主控制和管理等功能综合在一个以微处理机为主的系统中,达到信息共享.关键技术包括嵌入式计算机系统技术、数据总线技术、大容量存储技术和微型元器件技术.发展方向是小型化和集成化.  相似文献   

10.
《中国航天》2008,(4):27
俄罗斯主管军事工业的第一副总理伊万诺夫1月23日在俄联邦航天局理事会会议上说,如航天发射仍是俄在该领域的唯一业务,俄将有变成"太空出租司机"的危险.他说:"俄航天局如今赚得的大部分收入是靠发射外国卫星.  相似文献   

11.
A string moving with geostationary angular velocity in its radial relative equilibrium configuration around the Earth, reaching from the surface of the Earth far beyond the geostationary height, could be used as track for an Earth to space elevator. This is an old dream of mankind, originating about 100 years ago in Russia. Besides the question of feasibility from a technological point of view also the question concerning the stability of such a configuration has not yet been completely solved. Under the assumption that a proper material (carbon nanotubes) is available, making the connection possible technologically, we address the question of existence and stability of the radial relative equilibrium of a tapered string on a circular geosynchronous trajectory around the Earth, reaching from the surface of the Earth far beyond the geostationary height.  相似文献   

12.
In this paper, we analyze the illumination conditions, the thermal regime, and the possibility of deposits of volatile compounds existing in the vicinity region (NSR S5 region) near the southern pole of the Moon. It has been found that there are no permanently shadowed zones near the Scott crater and the NSR S5 region, though the temperature conditions allow the of compounds such as CH3OH, SO2, NH3, CO2, H2S, C2H4, and water to remain stable relative to evaporation for a long time (≥1 Gyr). It has been also shown that compounds like CO and CH4 cannot stably exist in these regions.  相似文献   

13.
对老年人体育锻炼负荷量监控方法的探讨   总被引:2,自引:0,他引:2  
通过对老年人体育锻炼活动的情况进行相关调查,发现目前老年人体育锻炼中存在一些误区。因此本文针对这些现实情况提出,应根据实际情况运用一些简单易行的方法来对老年人体育锻炼实施医务监督,达到提高老年人体育锻炼的科学性。  相似文献   

14.
The results of an investigation of the distribution of plasma pressure, pressure gradients, and magnetic field near the equatorial plane in the plasma ring surrounding the Earth under magneto-quiet conditions are presented. Observational data obtained during the international THEMIS mission are used. The picture of the distribution of transverse-current density near the equatorial plane was obtained under assumption of observing the magnetostatic balance condition at geocentric distances from 6 to 12R E. In estimating the integral transverse current it was accepted that in daytime sector the magnetic-field minima on magnetic field lines are not localized in the equatorial plane. Estimates of the integral transverse current were obtained, which demonstrate the possibility of closing nighttime transverse currents at geocentric distances of up to ~12R E inside the magnetosphere, which form a high-latitudinal continuation of the ring current.  相似文献   

15.
本文介绍了“三位一体”教育模式的内容,描述亍我们实施该模式所采取的措施及取得的成效。实践表明,“三位一体”教育模式能够提高学生的综合素质,为学生毕业后的发展打下坚实基础,对教育模式的改革具有一定的指导意义。  相似文献   

16.
The paper has studied the accuracy of the technique that allows the rotational motion of the Earth artificial satellites (AES) to be reconstructed based on the data of onboard measurements of angular velocity vectors and the strength of the Earth magnetic field (EMF). The technique is based on kinematic equations of the rotational motion of a rigid body. Both types of measurement data collected over some time interval have been processed jointly. The angular velocity measurements have been approximated using convenient formulas, which are substituted into the kinematic differential equations for the quaternion that specifies the transition from the body-fixed coordinate system of a satellite to the inertial coordinate system. Thus obtained equations represent a kinematic model of the rotational motion of a satellite. The solution of these equations, which approximate real motion, has been found by the least-square method from the condition of best fitting between the data of measurements of the EMF strength vector and its calculated values. The accuracy of the technique has been estimated by processing the data obtained from the board of the service module of the International Space Station (ISS). The reconstruction of station motion using the aforementioned technique has been compared with the telemetry data on the actual motion of the station. The technique has allowed us to reconstruct the station motion in the orbital orientation mode with a maximum error less than 0.6° and the turns with a maximal error of less than 1.2°.  相似文献   

17.
The possibility of the spacecraft insertion into the system of operational heliocentric orbits has been analyzed. It has been proposed to use a system of several operational heliocentric orbits. On each orbit, the spacecraft makes one or more revolutions around the Sun. These orbits are characterized by a relatively small perihelion radius and relatively high inclination, which allows one to investigate the polar regions of the Sun. The transition of the spacecraft from one orbit to another has been performed using an unpowered gravity assist maneuver near Venus and does not require the cruise propulsion operation. Each maneuver transfers the spacecraft into the sequence of operational heliocentric orbits. We have analyzed several systems of operational heliocentric orbits into which the spacecraft can be inserted by means of the considered transportation system with electric propulsion (EP). The mass of the spacecraft delivered to these systems of operational orbits has been estimated.  相似文献   

18.
电阻式传感器的核心部件——电阻应变计是目前最常用的应力分析的敏感元件。也常用于测量力、压力、扭矩和加速度等物理量。作者简要回顾了电阻应变计的发展历史,介绍了电阻应变计的结构、分类及现状,展望了电阻式传感器的前景。  相似文献   

19.
The results of modeling the dynamics of the Space Radiotelescope are presented. The results of ground-based vibration-dynamic tests are used to validate the calculation models and estimate the damping levels. The dynamic distortions of the reflecting surface caused by the operation of the pointing mechanism of the high-gain antenna are estimated.  相似文献   

20.
论文简略介绍了静力轴压下园柱壳屈曲应力的工程计算方法,对某固体火箭发动机壳体的复杂受载条件对壳体屈曲应力的影响进行了分析,并对该火箭发动机壳体屈曲应力如何估计提出了建议。  相似文献   

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