The RadioAstron project: Measurements and analysis of basic parameters of space telescope in flight in 2011–2013

The results of a large number of the antenna radiometric measurements at bands of 92, 18, 6.2, 1.35, and 1.7-1.2 cm are presented by the data of the standard telemetry system of the Spektr-R spacecraft. Both special sessions of calibration object observations in the mode of a single space radio telescope (SRT) operation and numerous observations of researched sources in the mode of the ground-space interferometer were used. The obtained results agree with the first results of Kardashev et al. (2013), i.e., within 10–15% at bands of 92, 18, and 6.2 cm and 20–25% at the band of 1.35 cm. In the main, the measurements for the eight subbands at wavelengths of 1.7-1.2 cm indicate a monotonic increase in the spectral system equivalent flux density (SEFD) of noise radiation with a frequency consistent with the calculated estimates for the discussed model. The sensitivity of the ground-space interferometer for the five subbands at wavelengths from 1.35 to 1.7 cm can be higher by a factor of 1.5, and for the three subbands from 1.35 to 1.2 cm lower by a factor of 1.5 than at the band of 1.35 cm. The SRT contribution to the interferometer sensitivity proportional to the square root of SEFD is close to the design one at the bands of 92 and 18 cm and decreases the design sensitivity approximately by a factor of 1.5 and 2 at the bands of 6.2 and 1.35 cm, respectively. These differences of implemented values from the design ones were not significantly affected the scientific program implementation.     

Trends in space life support.

Considerable progress has been made in recent years on development of candidate physico-chemical components for use in regenerative life support systems (LSS) for future extended-duration-mission spacecraft; these life support systems provide air revitalization including carbon dioxide reduction, water reclamation, and limited waste management. For still longer duration manned space flights, such as a permanently inhabited space station, it is generally recognized that development of biological life support systems capable of generating food and regenerating wastes will be essential to reduce logistics costs.     

Energy dependence of the characteristic decay time of proton fluxes in solar cosmic ray events

Energetic solar proton events within the energy interval 1–48 MeV at the stage of their decay are considered over the period of 1974–2001. The dependence of the characteristic decay time on the proton energy in the assumed power-law representation τ(E) =E ^?n is analyzed for the events with an exponential decay form. The dependence of n on the heliolongitude of the flare (the particles source on the Sun) is studied.     

On the correlation between individual biochemical parameters of human blood serum following space flight and their basal values

The article presents data concerning the osmolality and concentration of electrolytes and hormones regulating their balance for blood serum of 223 cosmonauts and astronauts. The obtained results allow us to judge the constancy of physicochemical parameters for the blood serum of healthy individuals and how they react to extreme conditions of space flight. The parameters used for evaluation included not just absolute values for the examined indices, but also how they responded to space flight, the dependence on baseline values and the interrelationship between ions. These data are important to predict the effect of exposure to extreme conditions and point to what extent the effect depends on the characteristics of the individual.     

Amplitude modulation of VLF emission and absorption of cosmic noise by <Emphasis Type="Italic">Pc</Emphasis>5 geomagnetic pulsations in the period of geomagnetic storms on October 30–31, 2003

Modulation of the VLF emission and riometric absorption by Pc5 geomagnetic pulsations is studied in the period of strong geomagnetic disturbances on October 30–31, 2003. Some conclusions about the regime of pitch-angular diffusion into the loss cone are made. The better coincidence of VLF emission modulation with geomagnetic pulsations in other longitude sectors is explained by the global character of excitation of the pulsations and by damping of their amplitudes at the meridian of observation of the VLF emission, which is associated with intensification of auroral electrojets.Translated from Kosmicheskie Issledovaniya, Vol. 42, No. 6, 2004, pp. 632–639.Original Russian Text Copyright © 2004 by Solovyev, Mullayarov, Baishev, Barkova, Samsonov.     

Dynamics of electron fluxes in the slot between radiation belts in November–December 2014 according to data of the <Emphasis Type="Italic">Vernov</Emphasis> satellite

The variations in the spatial structure and time in electron fluxes with E = 235–300 keV in the slot region (2 < L < 3) between the radiation belts in the period of November 1, 2014 through December 8, 2014 during weak and moderate geomagnetic disturbances (Kp < 4, Dst >–60 nT) are analyzed based on the data of the RELEC complex on board the Vernov satellite (the height and inclination of the orbit are from 640 to 830 km and 98.4°, respectively). Irregular increases in the fluxes of such electrons and formation of a local maximum at L ~ 2.2–3.0 were observed. It has been shown that the intensity of this maximum is inversely proportional to the L value and grows with an increase in the geomagnetic activity level. New features discovered for the first time in the dynamics of radiation belt electrons manifest in the variations in the local structure and dynamics of fluxes of subrelativistic electrons in the slot region.     

SAR ATR performance using a conditionally Gaussian model

A family of conditionally Gaussian signal models for synthetic aperture radar (SAR) imagery is presented, extending a related class of models developed for high resolution radar range profiles. This signal model is robust with respect to the variations of the complex-valued radar signals due to the coherent combination of returns from scatterers as those scatterers move through relative distances on the order of a wavelength of the transmitted signal (target speckle). The target type and the relative orientations of the sensor, target, and ground plane parameterize the conditionally Gaussian model. Based upon this model, algorithms to jointly estimate both the target type and pose are developed. Performance results for both target pose estimation and target recognition are presented for publicly released data from the MSTAR program     

A set of systems for labor standards computer-aided design

A set of systems for labor standard computer-aided design is described, namely, initial developments, advance and state-of-the art.     

Application of nonlinear filtering to navigation system designusing passive sensors

The problem of navigation system design for autonomous aircraft landing is addressed. New nonlinear filter structures are introduced to estimate the position and velocity of an aircraft with respect to a possibly moving landing site, such as a naval vessel, based on measurements provided by airborne vision and inertial sensors. By exploring the geometry of the navigation problem, the navigation filter dynamics are cast in the framework of linear parametrically varying systems (LPVs). Using this set-up, filter performance and stability are studied in an H_∞ setting by resorting to the theory of linear matrix inequalities (LMIs). The design of nonlinear, regionally stable filters to meet adequate H_∞ performance measures is thus converted into that of determining the feasibility of a related set of LMIs and finding a solution to them, if it exists. This is done by using-widely available numerical tools that borrow from convex optimization techniques. The mathematical framework that is required for integrated vision/inertial navigation system design is developed and a design example for an air vehicle landing on an aircraft carrier is detailed