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781.
782.
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   
783.
784.
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   
785.
786.
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   
787.
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   
788.
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   
789.
790.
Long-lived, stable jets are observed in a wide variety of systems, from protostars, through Galactic compact objects to active galactic nuclei (AGN). Magnetic fields play a central role in launching, accelerating, and collimating the jets through various media. The termination of jets in molecular clouds or the interstellar medium deposits enormous amounts of mechanical energy and momentum, and their interactions with the external medium, as well, in many cases, as the radiation processes by which they are observed, are intimately connected with the magnetic fields they carry. This review focuses on the properties and structures of magnetic fields in long-lived jets, from their launch from rotating magnetized young stars, black holes, and their accretion discs, to termination and beyond. We compare the results of theory, numerical simulations, and observations of these diverse systems and address similarities and differences between relativistic and non-relativistic jets in protostellar versus AGN systems. On the observational side, we focus primarily on jets driven by AGN because of the strong observational constraints on their magnetic field properties, and we discuss the links between the physics of these jets on all scales.  相似文献   
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