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261.
Sparaco P 《Aviation week & space technology》1996,145(19):49, 53-49, 55
Methods of fighting fatigue in airline pilots are reviewed. Recommendations include maintaining home base time, monitoring sleep, and time adjustments on extended layovers. Disorders related to the circadian rhythm include sleep disturbances, altered biological rhythms, and weakened mental performance. Drug therapy includes the use of stimulants such as coffee, tea, and cola; sleep pills; and oral administration of melatonin. 相似文献
262.
G. P. Anshakov A. I. Belousov A. V. Sedel’nikov A. S. Gorozhankina 《Russian Aeronautics (Iz VUZ)》2018,61(3):347-354
The influence of various control systems of the orbital motion of a technological spacecraft on the level of microacceleration of its internal environment is simulated. Conclusions are drawn about the effectiveness of control systems with different actuators for realization of certain gravitationally sensitive processes onboard a spacecraft. 相似文献
263.
Yu. M. Ignatkin P. V. Makeev V. I. Shaidakov A. I. Shomov 《Russian Aeronautics (Iz VUZ)》2018,61(3):396-403
The research is conducted of aerodynamic performance of the Mi-8 helicopter main rotor in the hover state and the vertical descent state, including vortex ring states (VRSs). Total and distributed aerodynamic performance, wake patterns, and main rotor flow patterns are calculated. The findings and results were compared with those provided by other researchers. 相似文献
264.
P. V. Bulat M. P. Bulat I. A. Volobuev A. A. Levikhin 《Russian Aeronautics (Iz VUZ)》2018,61(3):420-424
The bearing capacity of hybrid segmented bearings with different groove systems is compared. The research establishes that the system with a crescent groove has the best characteristics. 相似文献
265.
A. V. Bogatyi R. V. El’nikov I. P. Nazarenko G. A. Popov S. A. Semenikhin 《Russian Aeronautics (Iz VUZ)》2018,61(3):445-451
The paper presents the research results of the effect of a capacitor energy storage device configuration on the specific characteristics of advanced modern propulsion systems based on the ablative pulsed plasma thrusters (APPT). These thrusters are designed to perform specific tasks within the small spacecrafts with the onboard power capacity up to 200 W. 相似文献
266.
267.
Savkin A.V. Pathirana P.N. Faruqi F.A. 《IEEE transactions on aerospace and electronic systems》2003,39(3):901-910
Addressed here is the precision missile guidance problem where the successful intercept criterion has been defined in terms of both minimizing the miss distance and controlling the missile body attitude with respect to the target at the terminal point. We show that the H/sup /spl infin// control theory, when suitably modified, provides an effective framework for the precision missile guidance problem. The existence of feedback controllers (guidance laws) is investigated for the case of finite horizon and non-zero initial conditions. Both state feedback and output feedback implementations are explored. 相似文献
268.
The Role and Contributions of Energetic Neutral Atom (ENA) Imaging in Magnetospheric Substorm Research 总被引:2,自引:0,他引:2
Pollock C.J. C:son-Brandt P. Burch J.L. Henderson M.G. Jahn J.-M. McComas D.J. Mende S.B. Mitchell D.G. Reeves G.D. Scime E.E. Skoug R.M. Thomsen M. Valek P. 《Space Science Reviews》2003,109(1-4):155-182
Energetic Neutral Atom (ENA) imaging has contributed substantially to substorm research. This technique has allowed significant advances in areas such as observation and quantification of injected particle drift as a function of energy, observation of dynamics in the tail that are directly related to the effects of imposed (growth phase) and induced (expansion phase) electric fields on the plasma, the prompt extraction of oxygen from the ionosphere during substorms, the relationship between storms and substorms, and the timing of substorm ENA signatures. We present discussion of the advantages and shortcomings of the ENA technique for studying space plasmas. Although the technique is in its infancy, it is yielding results that enrich our understanding of the substorm process and its effects. 相似文献
269.
Tracking multiple objects with particle filtering 总被引:8,自引:0,他引:8
Hue C. Le Cadre J.-P. Perez P. 《IEEE transactions on aerospace and electronic systems》2002,38(3):791-812
We address the problem of multitarget tracking (MTT) encountered in many situations in signal or image processing. We consider stochastic dynamic systems detected by observation processes. The difficulty lies in the fact that the estimation of the states requires the assignment of the observations to the multiple targets. We propose an extension of the classical particle filter where the stochastic vector of assignment is estimated by a Gibbs sampler. This algorithm is used to estimate the trajectories of multiple targets from their noisy bearings, thus showing its ability to solve the data association problem. Moreover this algorithm is easily extended to multireceiver observations where the receivers can produce measurements of various nature with different frequencies. 相似文献
270.
V. A. Ryabyi V. A. Obukhov A. P. Kirpichnikov P. E. Masherov A. I. Mogulkin 《Russian Aeronautics (Iz VUZ)》2015,58(4):448-453
A technique of integral diagnostics for an RF inductively coupled plasma gas discharge unit of an ion thruster is proposed. This technique includes a priori measurements of antenna coil electrical parameters in free space and in assembled state as well as experimental determination of the antenna coil currents with and without discharge. 相似文献