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971.
A. A. Vostrukhin D. V. Golovin A. S. Kozyrev M. L. Litvak A. V. Malakhov I. G. Mitrofanov M. I. Mokrousov T. M. Tomilina Yu. I. Bobrovnitskiy A. S. Grebennikov M. M. Laktionova B. N. Bakhtin A. V. Sotov 《Cosmic Research》2018,56(3):208-212
The results of testing a number of space-based detectors that contain PMTs or high-voltage electrodes for the noise from the microphonics that occurs in the signal path due to external mechanical action have been presented. A method for the vibration isolation of instruments aboard a spacecraft has been proposed to reduce their responsivity to vibrations. 相似文献
972.
973.
The equations of the mathematical model are solved in terms of special functions. The results for the design scheme of the aircraft forebody are obtained with a guaranteed accuracy by the stable method of functional normalization. 相似文献
974.
Bleed air system is one of the most important components of air management system(AMS).It acts as transfer pipes responsible for air supply at high temperature and pressure.The thermal and flow performance of the bleed air system is a key issue for the design of AMS since the characteristics of air source have a great influence on the anti-ice system,the environmental control system and other downstream system in need of high temperature pressurized air.Based on the one-dimensional lumped parameter technology,a computer analysis model of bleed air system is developed in order to analyze the thermal and flow behaviors of the nodal points in the pipeline network.The simulation are performed with a given flight assignment using the analysis model,and the results verify that the system meets the design requirements. 相似文献
975.
Shyh-Biau Jiang Tse-Liang Yeh Li-Wu Chen Jann-Yenq Liu Ming-Hsuan Yu Yu-Qin Huang Chen-Kiang Chiang Chung-Jen Chou 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(10):2673-2679
In this study, we construct a photomultiplier calibration system. This calibration system can help scientists measuring and establishing the characteristic curve of the photon count versus light intensity. The system uses an innovative 10-fold optical attenuator to enable an optical power meter to calibrate photomultiplier tubes which have the resolution being much greater than that of the optical power meter. A simulation is firstly conducted to validate the feasibility of the system, and then the system construction, including optical design, circuit design, and software algorithm, is realized. The simulation generally agrees with measurement data of the constructed system, which are further used to establish the characteristic curve of the photon count versus light intensity. 相似文献
976.
A. A. Ryabov V. I. Romanov V. N. Rechkin Yu. N. Shmotin A. V. Veselov 《Russian Aeronautics (Iz VUZ)》2011,54(4):379-386
A computational technique, developed for analysis of strength, stability and low-cycle durability of GTE exhaust frame complex
structure under operational and emergency loads is described. The presented technique, based on the ANSYS and STAR-CD engineering
analysis software, and self-design software can improve the accuracy and efficiency of calculations, and reduce efforts on
finite element mesh development, performing calculations and processing of results. 相似文献
977.
郑禹 《沈阳航空工业学院学报》2011,28(6):53-56
近年来,中国的外语学习出现了低龄化的趋势,各种双语早教班和幼儿园的出现似乎在提醒人们,外语学习越早越好。语言习得关键期假说也成为二语习得领域的研究重点之一,语言学者们在外语学习的起始年龄对外语学习效率的影响力方面无法达成共识。在对比分析关键期相关研究的基础上,通过实证研究试图证明不同年龄开始接触英语的学习者在语言能力方面并没有显示出明显的差异,关键期假说不适用于主要基于学校教学的外语教学。 相似文献
978.
979.
Yu. Ya. Fershalov 《Russian Aeronautics (Iz VUZ)》2012,55(4):424-429
In this paper, a technique for the refined determination of turbine stage model parameters to investigate gasodynamic processes in the turbine flow passages without regard to uncontrolled heat exchange with environment is suggested. 相似文献
980.
Guidance law of a homing missile is implemented using an extended high gain observer without the model assumptions on target maneuvers. First, for a class of multi-input–multi-output nonlinear systems, extended high-gain observers are used for output feedback control with partial practical stabilization. Then the method is applied to the guidance law implementation of a homing missile with bearing only measurement. Simulation results show satisfactory performance. 相似文献