Variations of the gravitational field as a motive power for rhythmics of biochemical processes.

Variations of the gravitational field affected by the Sun and the Moon while the Earth's moving along the orbit seem to be a powerful source of many rhythmical processes typical of biochemical processes. Studies carried out in AARI revealed the obvious relationships between the dynamics of some biochemical reactions and lambda(D)-function describing the regular variations of the gravitational field under combined influence of the Sun and the Moon. The following of them are examined as examples: the rate of the unithiol oxidation in vitro, concentration of the thiol compounds in human urine, some hematological indicators (rate of the erythrocytes sedimentation, hemoglobin content). Compatibility of run of the biochemical indicators and lambda(D)-function is indicative of essential influence of the regular variations of the gravitational field on rhythmics of the biochemical processes. As this takes place, the solar activity acts like to the instability factor. Balance of the solar activity effects and the varying gravitational field effect alter in time depending on location in the solar activity cycle.     

Stable-Member Mounted Instrument Environment Simulation Model Development

The equations of motion for the stable member of a threegimbal platform are presented [3]. These equations are combined with models of the three platform control loops to formulate a model for the system. The system model is simplified and a digital simulation is developed for studying the motion of the stable member under conditions of dynamic vehicle angular environment.     

Comparison of A1-absorption data with theoretically computed values based on the International Reference Ionosphere (IRI)

Total absorption of hf radio waves at vertical incidence is calculated using the IRI electron density N(h) profiles at a low latitude for low and high solar activities and the calculated values of absorption are compared with the observed values. It is found that the IRI model holds good in this respect only for equinoxial months in years of low solar acitvity; however, it yields much higher values of absorption than observed during years of high solar activity (all seasons). It is suggested that seasonal anomalous variations of gas composition and bottomside thickness of the E-layer may be given due weight in revising the IRI.     

Passive Array Tracking of a Continuous Wave Transmitting Projectile

Differential Doppler measurements by a passive array are used to track an unstable continuous wave (CW) source moving in a ballistic trajectory, e.g., a projectile carrying a proximity fuse. The ballistic equations of motion couple frequency measurements at various sections along the track with the track parameters at any arbitrary time, e.g., at impact. A nonlinear weighted leastsquare method is used to estimate the track parameters, and the resulting error covariance matrix is derived. A numerical example demonstrates the relative contributions of various frequency measurements to the estimation accuracy.     

Performances of order statistics CFAR

A previous analysis of order-statistics constant-false-alarm-rate (OS-CFAR) radar receiving a single pulse from a Rayleigh fluctuating target in a Rayleigh background is extended to a Rayleigh-plus-dominant target. The analysis includes effects of a multitarget environment. A detailed comparison of OS-CFAR, cell-averaging (CA) CFAR, and censored CA-CFAR is provided for a Rayleigh target in the presence of strongly interfering targets. The false-alarm analysis of OS-CFAR is extended to the more general case of a Weibull background. The deterioration of the CFAR property of OS as the shape factor, C, of a Weibull probability density function changes from Rayleigh (C=2) to a longer-tailed one (C<2) is evaluated. The analytic comparison between CA-CFAR and OS-CFAR is extended to an integration of pulses reflected from a Swerling II target. The OS-CFAR performance (with and without interfering targets) yields an integral equation that is solved numerically     

The Onset of Long Term Modulation in the Heliosphere in Cycle 23

The combination of Voyager 1 (77.9 AU, 34.4° N) and Voyager 2 (61.2 AU, 24.5° S) at moderate heliolatitudes in the distant heliosphere and Ulysses with its unique latitudinal surveys in the inner heliosphere along with IMP 8 and other satellites at 1 AU constitutes a network of observatories that are ideally suited to study cosmic rays over the solar minimum of cycle 22 and the onset of solar activity and the long term cosmic ray modulation of cycle 23. Through 2000.7 there have been three well-defined step decreases in the cosmic ray intensity at 1 AU with the cumulative effect being in good agreement with the net decrease in cycle 21 at a comparable time in the solar cycle. Over this period the intensity changes at Ulysses are similar to those at 1 AU. In the distant heliosphere the initial decreases appear to be smaller than those at 1 AU. However the full effects of the interplanetary disturbances producing the most recent and largest step decrease in the inner heliosphere have not yet reached V-2. This revised version was published online in August 2006 with corrections to the Cover Date.     

Acceleration of particles by shocks in a cosmic plasma

The theory and observational evidence pertaining to particle acceleration by shock waves in astrophysical objects and in space are systematized. Recent works showing observational and theoretical aspects of the problem dealing with shocks in turbulent media are emphasized. The acceleration of particles by shocks in turbulent media is observed in interplanetary space. This acceleration mechanism is of particular interest from the point of view of the origin of cosmic rays, providing the degree form of the spectrum. The index of the spectrum is close to the observable one for galactic cosmic rays. It depends slightly on specific conditions in the acceleration region. Electron and nucleus acceleration in supernova remnants and in radiogalaxies is discussed, and theory and observational data are compared. The theory of particle acceleration by supersonic turbulence is outlined.     

The use of stereoscopic satellite observation in the determination of the emissivity of cirrus

The feasibility of determining cirrus “emissivity” from combined stereoscopic and infrared satellite observations in conjunction with radiosounding data is investigated for a particular case study. Simultaneous visible images obtained during SESAME-1979 from two geosynchronous GOES meteorological satellites were processed on the NASA/Goddard interactive system (AOIPS) and were used to determine the stereo cloud top height Z_C as described by Hasler [1]. Iso-contours of radiances were outlined on the corresponding infrared image. Total brightness temperature T_B and ground surface brightness temperature T_S were inferred from the radiances. The special SESAME network of radiosoundings was used to determine the cloud top temperature T_CLD at the level defined by Z_C. The “effective cirrus emissivity” NE where N is the fractional cirrus cloudiness and E is the emissivity in a GOES infrared picture element of about 10 km × 10 km is then computed from T_B, T_S and T_CLD.