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361.
The problem of determining the “potential” number of integration steps by explicit difference schemes is solved within the framework of the prediction model for chemically non-equilibrium processes. 相似文献
362.
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
363.
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
364.
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
365.
366.
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
367.
We consider in detail the intense Pc5 pulsations of the magnetic field, riometric absorption, and electron fluxes occurred
on the recovery phase of the strong magnetic storm on November 21, 2003. The global structure of these disturbances is studied
using the world network of magnetometers and riometers supplemented by the data of particle detectors onboard the LANL geosynchronous satellites. The local spatial structure is investigated according to data of the regional network of Finnish
vertical riometers and of stations of the IMAGE magnetic network. Though a certain similarity is observed in the frequency
composition and time evolution of the variations of magnetic field and riometric absorption, the local spatial structure of
these oscillations turns out to be different. It is suggested that these variations can be manifestations of oscillatory properties
of two weakly connected systems: the magnetospheric MHD waveguide/resonator and the system cyclotron noise + electrons. The
recorded Pc5 oscillations are, presumably, a result of excitation of the magnetospheric waveguide on the morning and evening
flanks of the magnetosphere. At high velocities of the solar wind this waveguide can appear in a metastable state. Not only
jumps in the solar wind density, but injection of electrons into the magnetosphere as well, can serve as a trigger for the
waveguide excitation. 相似文献
368.
This paper proposes a novel landing gear for spacecraft that allows a weight reduction due to using deformable crash legs. Numerical simulation of the landing process was performed. 相似文献
369.
G. S. Anufriev 《Cosmic Research》2010,48(1):101-107
The isotopic composition and concentrations of helium are investigated in 9 samples taken from different depths of a soil
column delivered by the Luna-24 mission. It is demonstrated that, with allowance made for random errors, the isotopic composition of helium remains invariable.
The concentrations of helium are subject to considerable variations, the increases and decreases relative to the average value
reaching a factor of 1.5–2. Assuming that the full length of the soil column was formed due to long-term accumulation of lunar
clastic rocks (regolith), based on measurements of cosmogenic isotopes, a method of determining the rate of regolith accumulation
has been developed, as well as a method of determining the age of the column soil samples. It is found that the rate of regolith
accumulation is variable, and it changes over the column length within the limits (0.2–0.8 cm)/106 years. The range of the time for formation of the investigated part of the column is 100–600 million years. The observed
decreases of concentration (at 250 and 600 million years) can be associated with both solar and lunar processes. In particular,
a possibility of diffusion losses of helium due to the mechanism of jump-like diffusion is discussed, and diffusion parameters
are found. A comparison of time periods of the observed variations in the solar wind with paleontological epochs and periods
is made. 相似文献
370.
Dynamics of planets around other stars that demonstrate a variety of possible characteristics is of interest from the point
of view of realization of new scenarios of evolution which have not been realized in the Solar System. We consider the rotational
evolution of exoplanets under the action of gravitational perturbations and magnetic disturbances using the methods of quality
analysis and theory of bifurcation of multiparametric differential equations that describe evolution of non-resonant rotation
of a dynamically symmetric planet magnetized along its symmetry axis. We analyze 64 phase portraits describing the evolution
of angular momentum vector L for all possible values of planet parameters. The values of parameters are determined for the case when the direct rotation
of a planet is changed for its retrograde rotation. 相似文献