Communication System Architecture for Air Traffic Management and Weather Information Dissemination

The authors present the communication system architecture for air traffic management and weather information dissemination as viewed within the context of the overall National Airspace System (NAS) and the services it provides. This presents the architecture in the 2015 time frame when the final phases of transition take place from analog voice to digital data exchange of common data via integrated networks. The results of this transition are an integrated collection of systems and procedures that efficiently use the capacity of the NAS while balancing access to all user classes and maintaining the highest levels of safety. Efficient collaboration among users is built on a foundation of common data. This information base provides common situational awareness to all participants. All users are accommodated and will receive benefits commensurate with equipage level. This architecture development provides a technical framework for decision-making, research, and analysis of communication technologies     

ATE enabling technologies

A discussion of the current and emerging core technologies and philosophies that will enable Air Force personnel to quickly, accurately and intuitively diagnose faults in increasingly complex systems     

Gamow and the physics and evolution of stars

The high temperature sensitivity of thermonuclear reactions and the neurrino emission at the final stages of stellar evolution (urca process) are the most crucial Gamow's contribution to the physics and evolution of stars. G. Gamow made one of a few first attempts in astrophysics to get a comprehensive picture of stellar evolution from the main sequence (thenormal stars in his terminology) through the formation of white dwarfs, gravitational collapse of stellar cores and supernova explosions.     

Ultra-wideband ground-penetrating radar for the detection of buriedmetallic mines

The suitability of ultra-wideband ground-penetrating radar as a tool for the detection of buried metallic mines is explored in this paper. The analysis centers around a 200-800 MHz, dual-polarized ground penetrating radar (GPR) designed and built by SRI International. The analysis consisted of fusing the images from the dual polarizations into a single image to enhance the target objects and suppress clutter. Results are shown for several variations of a Mahalanobis-based fusion technique, and “soft decision” minefield detection results based upon Monte Carlo statistical techniques are also presented. Although relatively few scenes were analyzed, these results show that the dual-polarized GPR is potentially very effective at finding buried mines and minefields     

Venus Express: Scientific goals, instrumentation, and scenario of the mission

The first European mission to Venus (Venus Express) is described. It is based on a repeated use of the Mars Express design with minor modifications dictated in the main by more severe thermal environment at Venus. The main scientific task of the mission is global exploration of the Venusian atmosphere, circumplanetary plasma, and the planet surface from an orbiting spacecraft. The Venus Express payload includes seven instruments, five of which are inherited from the missions Mars Express and Rosetta. Two instruments were specially designed for Venus Express. The advantages of Venus Express in comparison with previous missions are in using advanced instrumentation and methods of remote sounding, as well as a spacecraft with a broad spectrum of capabilities of orbital observations.     

The Motion of Coaxial Bodies of Varying Composition on the Active Leg of Descent

The motion of a spacecraft (SC) with double rotation and variable mass on the active leg of its descent is considered. The SC consists of two coaxial bodies. The coaxial scheme is used for gyroscopic stabilization of the SC longitudinal axis by the method of partial spin-up. The equations of spatial motion of coaxial bodies of varying composition are derived and approximate solutions for the angles of spatial orientation are found. The condition of decreasing amplitude of nutation oscillations is obtained, which allows the estimation of efficiency of the stabilization by partial spin-up. The errors in the magnitude and direction of the vector of braking thrust are also determined.__________Translated from Kosmicheskie Issledovaniya, Vol. 43, No. 3, 2005, pp. 224–232.Original Russian Text Copyright © 2005 by Aslanov, Doroshin, Kruglov.     

Usefulness of daily +2Gz load as a countermeasure against physiological problems during weightlessness.

Adaptation to head-down-tilt bed rest as a simulated microgravity leads to an abnormality of reflex control of circulation, hypovolemia and reduction of exercise capacity. We hypothesized that this cardiovascular deconditioning and reduction of exercise capacity could be prevented by a daily 1 hr centrifugation at +2Gz. To test this hypothesis, twenty healthy male subjects underwent 4 day of 6 degrees head-down-tilt bed rest. Ten of them were exposed to a +2Gz load for up to 30 min twice per day (the Gz group). The remaining 10 were not exposed to a Gz load (the no-Gz group). We estimated autonomic cardiovascular control by power spectral analysis of blood pressure and R-R interval variability, and baroreflex regulation by the transfer function analysis and the sequence method, before and after bed rest. Further, we measured hematocrit as an index of changes in plasma volume and maximal oxygen consumption as an index of exercise capacity, before and after bed rest. Result: In the no-Gz group, heart rate increased after bed rest. The high frequency power of R-R interval variability as an index of cardiac parasympathetic nervous activity, baroreflex gains estimated by transfer function analysis and the sequence method as index of the integrated arterial-cardiac baroreflex function decreased significantly. Associated with these changes, the ratio of low to high frequency power of R-R as an indicator of cardiac sympathovagal balance tended to increase after bed rest in the no-Gz group. However, those showed no significant changes after bed rest in the Gz group. Hematocrit increased after bed rest in the no-Gz group. It also tended to increase in the Gz group, however it did not achieve statistical significance. Maximal oxygen consumption decreased significantly to similar extent in both the groups. Conclusion: This result suggested that 1) a daily 1hr +2Gz load produced by a centrifuge might eliminate the changes in autonomic cardiovascular control during simulated weightlessness; 2) furthermore, it might partly reverse hypovolemia induced by bed rest; 3) however, it could not prevent the decreases in exercise capacity.     

Relaxation of electron and proton radiation belts of the earth after strong magnetic storms

During strong magnetic storms in July and November of 2004 the fluxes of trapped particles (protons and electrons of MeV energies) in the Earth’s radiation belts have increased by orders of magnitude and then decreased remaining on an enhanced level for several months. These enhancements allowed us to study the processes of relaxation of the radiation belts. Measurements of energetic particles by low-altitude satellites Coronas-F and Servis-1 have shown that predictions of the theory about the rate of pitch-angle diffusion are not always correct, giving both overestimated and underestimated values for the lifetime of energetic particles.     

The observation of the galactic anticenter region by the balloon borne gamma-ray telescope Natalya-I

This paper presents the results of measurements of gamma radiation with energies above 5 MeV, from the galactic anticenter region. The balloon-borne gamma ray telescope “Natalya-I”, was launched on 6 November, 1980 from the Tata Institute of Fundamental Research's Balloon Facility (Hyderabad, India) and reached ceiling altitude of 35 km. The results on the accelerator calibration of the telescope, using a “tagged” gamma ray beam are also presented.