Konus-W gamma-ray burst experiment for the GGS Wind spacecraft

The Konus-W experiment to be flown on board the GGS-Wind spacecraft is designed to observe gamma-ray bursts and solar flares with moderate spectral and high time resolution. Two large scintillators are used to provide omnidirectional sensitivity. The primary scientific objectives are the study of the continuum energy spectra and spectral features of these events in the energy range of 10 keV to 10 MeV, as well as their time histories in soft, medium, and hard energy bands, with a time resolution to 2 ms.     

Measurement of the partial oxygen pressure and oxygen utilization in the skin of cosmonauts aboard Salyut 6

The oxygen tension (PO₂) in the dorsal skin surface of the forearm was studied during the stay of cosmonauts on board Salyut 6. Between the fourth and fifth day of stay on the orbital station a considerable reduction of the PO₂ level was observed. The oxygen utilization values were also reduced. In the early postflight period the low PO₂ level persisted, with gradual normalization.     

Estimating the number of signals using reference noise samples

Criteria for estimating the number of signals in the case of small-sample populations are considered. The criteria introduced by M. Wax and T. Kailath (1985) do not work well in this case. Two new criteria based on information theoretic and eigenmode composition-based criteria are proposed, assuming a known noise covariance. Simulation results show a significant improvement in the performance of estimating the number of signals in the small-sample case, by the use of the new criteria combined with an estimate of the noise covariance obtained from reference noise samples     

An adaptive array detector with mismatched signal rejection

An adaptive detection algorithm with a sensibility parameter for rejecting unwanted signals is presented. This algorithm is a simple modification of the generalized likelihood ratio (GLR) detector (or test) for detecting a signal in zero mean Gaussian noise with unknown correlation matrix. Specifically, the adaptive detection algorithm is obtained by introducing an arbitrary positive scalar, which is called the sensitivity parameter, into the GLR detector as a multiplier of an already existing quadratic term. The GLR detector then becomes a special case of this detector for the unity sensitivity parameter. It is shown that the sensitivity parameter controls the degree to which unwanted signals are rejected. From numerical examples, it is demonstrated how the sensitivity parameter can be chosen such that unwanted signals, can be rejected while maintaining acceptable detection loss for slightly mismatched signals. Further insight into previous work on adaptive detection is also given     

International cooperation in remote sensing for global change research: political and economic considerations

Activities concerning international cooperation in space-based remote sensing for global change research have for the most part focused on technical/functional aspects such as data harmonization, research project coordination, and sensor selection and deployment. Until fairly recently, little attention has been directed towards the various political and economic constraints which may act as ‘stumbling blocks’. A review of the contemporary international remote sensing milieu as it relates to the global change research agenda is presented. Several important political and economic conditions affecting this area are identified: (1) data access and pricing policies; (2) national security concerns; (3) developed/developing nation relations; and (4) inconsistent political/financial commitments. A set of recommendations is offered to enhance international cooperation in the use of space-based remote sensing data for global change research.     

Dynamic and figure parameters of Venus and Mars

Parameters of the best-fitting tri-axial ellipsoids representing external equipotential surfaces of Venus and Mars have been determined from satellite data. The dynamic consequence of the equatorial flattening of Venus has been discussed from the point of view of the s.c. synodic resonance rotation. The major gravitational anomalies of Venus have been interpreted, space locations and magnitudes of anomalous masses determined and their contribution to the second zonal Stokes' constant in the gravitational potential computed. The conclusions were done: The figure of the aphroditoid is strange even if there is a relatively small polar flattening; an equatorial “disc” of Venus is enormous. Recent space data do not support hypothesis that the Earth controls the spin of Venus.     

Fast intelligent battery charging: neural-fuzzy approach

This paper focuses on the design of a super fast battery charger based on National's proprietary neural network based NeuFuz technology. In this application, we have used a NiCd battery pack as the test vehicle. However, this technology can be extended to other chemistries such as Ni-MH, Li-ion, etc. This technology allows the designer to accurately model the charge controller using a neural network, based on battery charge characteristics provided by the manufacturer. This approach continuously monitors the battery status, and modifies the charge current accordingly. It also eliminates the need for standard charge termination methods used in today's conventional chargers. The result is super fast charging in 20 to 30 minutes, and increased battery life. A low cost embedded controller (COP8) performs all the fuel-gauging and charge control functions by processing data obtained from the battery circuitry     

Cometary probe of the Venera-Halley mission

Venera-Halley mission is to be launched to Venus in Dec. 1984. It will fly by Venus in June 1985. Separation of the cometary probe and Venera descend module will take place at that time. The gravitational swing-by at Venus will provide the encounter with the Halley comet in March 1986. The remote sensing of the inner coma (TV-imagery, spectrometry in the region from 1200 A to 12 μm, polarimetry) and of the nucleus, direct measurements of dust fluxes, dust composition, plasma and magnetic field are planned in the framework of multinational cooperation.     

Application of the method of potentials in problems of fracture mechanics

The theory of generalized elastic potentials is used for solving the problem of a space with cracks of arbitrary shape. Two solutions are proposed. In the first case, the solution is represented by a double-layer potential and a functional equation for determination of the unknown density is constructed in which difficulties stipulated by high polarity of the integrand may be eliminated. The other method consists of an analysis of a space with a thin smooth cavity and the solution of corresponding singular integral equations.Methods to improve the convergence of successive approximations used in solution of the equations are described and some particular cases of three-dimensional solids are considered. A special function is introduced on the external surface of the solid, which allows consideration of a whole space with cracks having fictitious stresses on their edges; this solution has some bearing on the main problem and also provides an integral equation for the auxiliary function. Another approach consists of the elimination of cracks by introduction of corresponding potentials and solution of the auxiliary problem for a continuous solid with special boundary conditions.