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841.
E A Krasavin S Kozubek K G Amirtayev B Tokarova M Bonev 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1992,12(2-3):103-110
The peculiarities and mechanisms of the mutagenic action of gamma-rays and heavy ions on bacterial cells have been investigated. Direct mutations in the lac-operon of E. coli in wild type cells and repair deficient strains have been detected. Furthermore, the induction of revertants in Salmonella tester strains was measured. It was found that the mutation rate was a linear-quadratic function of dose in the case of both gamma-rays and heavy ions with LET up to 200 keV/micrometer. The relative biological effectiveness (RBE) increased with LET up to 20 keV/micrometer. Low mutation rates were observed in repair deficient mutants with a block of SOS-induction. The induction of SOS-repair by ionizing radiation has been investigated by means of the "SOS-chromotest" and lambda-prophage induction. It was shown that the intensity of the SOS-induction in E. coli increased with increasing LET up to 40-60 keV/micrometer. 相似文献
842.
843.
在简要介绍了飞行器视觉图像定位导航原理及模型的基础上,针对其非线性模型的推广Kalman滤波的收敛与初始条件有关的问题,将其定位导航的两种模型(线性与非线性模型)组合,提出了双模态双滤波器滤波方法。这种滤波能很好地解决非线性推广Kalman滤波的收敛问题。通过第一个线性滤波器的滤波估计给第二个非线性滤波器提供滤波初值,使这一非线性滤波收敛,并能取得较高的滤波精度。 相似文献
844.
V. T. Grumondz E. I. Karpezhnikov M. A. Polishchuk M. V. Polishchuk 《Russian Aeronautics (Iz VUZ)》2017,60(4):534-541
The algorithms of controlled descent for unmanned winged gliders are designed taking into account the requirements to the flight trajectory. The calculation results are represented to show the efficiency of the algorithms. 相似文献
845.
R.A. Gowen A. Smith A.D. Fortes S. Barber P. Brown P. Church G. Collinson A.J. Coates G. Collins I.A. Crawford V. Dehant J. Chela-Flores A.D. Griffiths P.M. Grindrod L.I. Gurvits A. Hagermann H. Hussmann R. Jaumann A.P. Jones K.H. Joy O. Karatekin K. Miljkovic E. Palomba W.T. Pike O. Prieto-Ballesteros F. Raulin M.A. Sephton S. Sheridan M. Sims M.C. Storrie-Lombardi R. Ambrosi J. Fielding G. Fraser Y. Gao G.H. Jones G. Kargl W.J. Karl A. Macagnano A. Mukherjee J.P. Muller A. Phipps D. Pullan L. Richter F. Sohl J. Snape J. Sykes N. Wells 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
846.
A technique of evaluating the micromechanical characteristics (namely, microhardness, microdurability, microbrittleness and
static crack resistance coefficient) using microindentation as applied to plasma zirconia-based thermal barrier coatings is
presented. 相似文献
847.
848.
V. A. Ivanov D. V. Ivanov N. V. Ryabova Luong Viet Loc E. V. Katkov 《Russian Aeronautics (Iz VUZ)》2017,60(2):286-291
The paper presents the methods and algorithms for positioning the dynamic (moving) objects using the oblique-incidence ionospheric sounding by chirp signals. Full-scale experiments have been performed to determine a distance to an object and its location. 相似文献
849.
D. J. McComas E. R. Christian N. A. Schwadron N. Fox J. Westlake F. Allegrini D. N. Baker D. Biesecker M. Bzowski G. Clark C. M. S. Cohen I. Cohen M. A. Dayeh R. Decker G. A. de Nolfo M. I. Desai R. W. Ebert H. A. Elliott H. Fahr P. C. Frisch H. O. Funsten S. A. Fuselier A. Galli A. B. Galvin J. Giacalone M. Gkioulidou F. Guo M. Horanyi P. Isenberg P. Janzen L. M. Kistler K. Korreck M. A. Kubiak H. Kucharek B. A. Larsen R. A. Leske N. Lugaz J. Luhmann W. Matthaeus D. Mitchell E. Moebius K. Ogasawara D. B. Reisenfeld J. D. Richardson C. T. Russell J. M. Sokół H. E. Spence R. Skoug Z. Sternovsky P. Swaczyna J. R. Szalay M. Tokumaru M. E. Wiedenbeck P. Wurz G. P. Zank E. J. Zirnstein 《Space Science Reviews》2018,214(8):116
The Interstellar Mapping and Acceleration Probe (IMAP) is a revolutionary mission that simultaneously investigates two of the most important overarching issues in Heliophysics today: the acceleration of energetic particles and interaction of the solar wind with the local interstellar medium. While seemingly disparate, these are intimately coupled because particles accelerated in the inner heliosphere play critical roles in the outer heliospheric interaction. Selected by NASA in 2018, IMAP is planned to launch in 2024. The IMAP spacecraft is a simple sun-pointed spinner in orbit about the Sun-Earth L1 point. IMAP’s ten instruments provide a complete and synergistic set of observations to simultaneously dissect the particle injection and acceleration processes at 1 AU while remotely probing the global heliospheric interaction and its response to particle populations generated by these processes. In situ at 1 AU, IMAP provides detailed observations of solar wind electrons and ions; suprathermal, pickup, and energetic ions; and the interplanetary magnetic field. For the outer heliosphere interaction, IMAP provides advanced global observations of the remote plasma and energetic ions over a broad energy range via energetic neutral atom imaging, and precise observations of interstellar neutral atoms penetrating the heliosphere. Complementary observations of interstellar dust and the ultraviolet glow of interstellar neutrals further deepen the physical understanding from IMAP. IMAP also continuously broadcasts vital real-time space weather observations. Finally, IMAP engages the broader Heliophysics community through a variety of innovative opportunities. This paper summarizes the IMAP mission at the start of Phase A development. 相似文献
850.
E. S. Soldatkina 《Russian Aeronautics (Iz VUZ)》2013,56(3):291-296
Application prospects, a functional diagram and algorithms for processing informative signals from a vortex aerodynamic angle and true airspeed sensor are considered. The requirements for transducers of pressure pulsations downstream of vortex generators are formed, a technique and connection of these transducers to the sensor circuit diagram are described. A technique is presented to analyze individual and resultant errors of the aerodynamic angle and true airspeed channels. 相似文献