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441.
S. V. Falaleev 《Russian Aeronautics (Iz VUZ)》2017,60(2):229-235
The paper studies different types of dampers for rotor supports of gas turbine engines (GTE). The advantages of hydrodynamic dampers are shown. Hydrodynamic dampers for GTE rotor supports are studied. A new design and technique of calculation are proposed for an adjustable hydrodynamic damper. 相似文献
442.
In the paper, processes of high-energy electron beam interaction with plasma particles in a discharge channel of a stationary plasma thruster are analyzed and the results are presented. 相似文献
443.
Reconfiguration of multiprocessor systems makes it possible to improve their failure-resistance that is especially important for the integrated modular avionics systems. The algorithm considered in this paper allows minimizing the reservation and providing the better safety level and more effective flight completion or even its further execution in the case of failures of airborne equipment. 相似文献
444.
系统分析各类高性能制造以注重零件的几何尺寸精度所带来的问题,即在具备超精密、高精度加工能力后,由"合格的高精度零件"装配出的产品至今依然还是合格率低、参数稳定性差的本质内因.首次从零件制造微观角度提出了产品生产合格率低、参数稳定性差是由零件表面微观特征与产品技术特征非匹配性导致的,提出了全新的产品制造理念,从注重零件的几何尺寸精度向关注零件制造微观工艺特征与产品技术特征的匹配性和符合性转变.形成和建立起我国自主创新的高性能产品制造思想和产品制造工艺技术体系,才能从根本上解决产品生产制造合格率低、参数稳定性差等问题,才能形成有继承性、可持续、稳定的产品制造技术体系,而这一切是工业4.0制造模式无法解决的. 相似文献
445.
R. Manuel S.E.S. FerreiraM.S. Potgieter R.D. StraussN.E. Engelbrecht 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
Time-dependent cosmic ray modulation is calculated over multiple solar cycles using our well established two-dimensional time-dependent modulation model. Results are compared to Voyager 1, Ulysses and IMP cosmic ray observations to establish compatibility. A time-dependence in the diffusion and drift coefficients, implicitly contained in recent expressions derived by , , and , is incorporated into the cosmic ray modulation model. This results in calculations which are compatible with spacecraft observations on a global scale over consecutive solar cycles. This approach compares well to the successful compound approach of Ferreira and Potgieter (2004). For both these approaches the magnetic field magnitude, variance of the field and current sheet tilt angle values observed at Earth are transported time-dependently into the outer heliosphere. However, when results are compared to observations for extreme solar maximum, the computed step-like modulation is not as pronounced as observed. This indicates that some additional merging of these structures into more pronounced modulation barriers along the way is needed. 相似文献
446.
S. O. Karpenko N. V. Kupriyanova M. Yu. Ovchinnikov V. I. Penkov A. S. Selivanov O. E. Khromov 《Cosmic Research》2010,48(6):517-525
The results of designing the attitude control system of the first Russian nanosatellite TNS-0 no. 1 providing orientation of its longitudinal axis along the local geomagnetic field induction vector are presented. The system
consists of a permanent magnet and two sets of hysteresis rods. The magnetic and geometric parameters of the magnet and rods
are calculated. The influence of the permanent magnet field on the hysteresis rods and mutual influence of the rods in the
case of compact satellite packaging are analyzed. Examples of calculations of transient processes and steady-state angular
satellite motion are presented. 相似文献
447.
The Juno Waves Investigation 总被引:1,自引:0,他引:1
W. S. Kurth G. B. Hospodarsky D. L. Kirchner B. T. Mokrzycki T. F. Averkamp W. T. Robison C. W. Piker M. Sampl P. Zarka 《Space Science Reviews》2017,213(1-4):347-392
Jupiter is the source of the strongest planetary radio emissions in the solar system. Variations in these emissions are symptomatic of the dynamics of Jupiter’s magnetosphere and some have been directly associated with Jupiter’s auroras. The strongest radio emissions are associated with Io’s interaction with Jupiter’s magnetic field. In addition, plasma waves are thought to play important roles in the acceleration of energetic particles in the magnetosphere, some of which impact Jupiter’s upper atmosphere generating the auroras. Since the exploration of Jupiter’s polar magnetosphere is a major objective of the Juno mission, it is appropriate that a radio and plasma wave investigation is included in Juno’s payload. This paper describes the Waves instrument and the science it is to pursue as part of the Juno mission. 相似文献
448.
The paper discusses a method of designing the neural controller for two-channel control of a technical object by an example of the roll and yaw control depending on deviations, velocities and accelerations of their variation. 相似文献
449.
The methodology is proposed and the mathematical model is developed for the purpose of numerical simulation of the power circuit of the gas-hydraulic actuator with displacing power source for the gimbaled nozzle control. It provides the highest power efficiency factor of the actuator as a part of aircraft by means of pulling together the profiles of available and required power. 相似文献
450.
The paper presents an improved technique and the results of strength analysis for the aircraft structural elements with a structural defect like an arbitrary shape delamination. 相似文献