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791.
The key radiative processes are discussed, numerical methods of magnetized radiative transfer are presented, and these are considered in their application to X-ray pulsar models.  相似文献   
792.
The instrument IESP-IPMP represents the complex unit measuring the vector of the DC electric field, the vectors of the electric and magnetic field in the frequency range of 0.2 – 6.5 Hz (wave form), autocorrelation functions of waves with frequencies of 0.1 – 5 kHz, and wave amplitudes in 8 bandpass channels. Some results are shown and compared in the various frequency ranges.  相似文献   
793.
The 1985 International Solar Polar Mission will provide the first opportunity to perform measurements from out of the ecliptic and from above the solar poles. Included in this mission is the Zodiacal Light/Background Starlight Experiment of the Ruhr-University Bochum, FRG (in collaboration with the State University of New York at Albany). The experiment is based on the use of a multicolor, sky-scanning photopolarimeter, which will be carried on the NASA S/C.The scientific objectives of the experiment are to investigate the intensity, polarization, and color of the diffuse sky brightness and determine the spatial distribution and physical properties of the interplanetary dust, including a possible interstellar component, as a function of S/C position in and out of the ecliptic.The instrument will allow simultaneous measurements in two separate wavelength bands. Measurements will be performed at 180, 220, 240, 280, 320, 350, 360, 440, 540, 640, 800 nm, including the state of polarization. Two different fields-of-view (1 sq deg and 5.6 sq deg) can be selected.The use of a microprocessor system in the instrument electronics will provide flexibility in measurement sequences and programs, on-board data processing and data quality control.  相似文献   
794.
This paper analyzes a sequential feedback detection scheme derived by Kramer's nonsequential intermittent one; in addition to the noiseless information feedback channel, it makes use of a noiseless decision feedback channel. Expressions for the normalized average evergy per symbol, average decision time, probability of error, and average power are derived. The comparison with the nonsequential intermittent scheme shows that the proposed one allows an appreciable gain in transmission rate and requires a smaller peak-to-average power ratio.  相似文献   
795.
Plans for the various missions in which men and women are expected to participate during the next 10 years are outlined. Such missions include flights of up to three months duration in low earth orbit as well as possible short excursions to geosynchronous orbit. Research activities are described which cover the full spectrum of physiological and psychological responses to space flight. These activities are shown to contribute to the ongoing Shuttle program and the future Space Station. The paper includes a summary of the major technical thrusts needed to support extended habitation in space.  相似文献   
796.

The current state of knowledge concerning Birkeland currents (j ) and parallel electric field (E ) is briefly reviewed. Four types of j are discussed-the primary ‘region 1’ sheets, the ‘region 2’ sheets which parallel them and which seem to close in the partial ring current, the cusp currents which appear to correlate with interplanetary B y, and the ‘Harang filament’. The energy required by E and by the associated particle acceleration processes seems to be derived from j . Much of the evidence for e comes from particles, from ‘inverted V’ spectra, rising ion beams and expanded loss cones, while ‘conies’ may signify acceleration by Electrostatic Ion Cyclotron (EIC) waves, associated with beams accelerated by E . Different theoretical studies predict for E a smooth, disordered or abrupt structure, and evidence for all 3 types can be deduced from S3-3 electric field probe observations.

  相似文献   
797.
Available rocketsonde information has been used to compile tables of monthly mean temperature, pressure, density and zonal wind for the middle atmosphere of the southern hemisphere with the purpose of revising similar tables presented to COSPAR earlier. The altitude range is 25 to 80 km in steps of 5 km. The latitude range is 0° to 70°S with a 10° step. The compatability of different sets of temperature measurements is discussed. Mean values of temperature, pressure and zonal wind obtained for the southern hemisphere are compared with northern hemisphere model values. Large differences between the hemispheres (up to 20°C in temperature, 20–30% in pressure, 30–50 m/s in wind) imply that reference atmospheres such as CIRA should be complemented by southern hemisphere climatology.  相似文献   
798.
The concepts of "equivalent linear arrays" and "minimum effective spacing" can be used to simplify the analysis of planar adaptive arrays. The resulting design rules permit the rapid determination of array configurations without the need for computer modeling.  相似文献   
799.
800.
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