An analysis of magnetic protection of spacecraft against penetrating radiation

Negative effect of cosmic ray particles is a serious danger for astronauts and onboard equipment. When planning interplanetary flights it becomes one of the main obstacles. The aim of this work is to analyze currently available methods of protecting spacecraft against cosmic rays using magnetic fields and to choose the most effective method. Three variants of protection systems were considered, two of which had been described in scientific literature: with azimuth and axial magnetic filed. The third, more general method (with helical magnetic field) is suggested here for the first time. The first two variants are extreme special cases of the third one. The exact solution is obtained for the problem of motion of a charged relativistic particle in the helical magnetic field, and a criterion of particle reflection is determined. A comparative analysis of reflection characteristics of the chosen systems has been performed, and the conclusion about the optimal configuration of the magnetic protection is drawn.     

Investigation of direct integration for nonlinear finite element equations of motion by the modified central difference method

The investigation of stability and precision of the previously proposed implicit scheme of direct integration for the finite element equations of motion is presented. The scheme parameter values that ensure its unconditional stability in the nonlinear problems are determined and comparison with existing procedures is given.     

Simulation of liferaft string water drop

A mathematical model of motion for a string of liferafts being water dropped is presented under the assumption of a plane system motion. An example of calculations is given.     

A Problem of choosing an optimal number of information unmanned aerial vehicles

Using formalism of the queueing theory, we propose two-objective models for optimizing the number of unmanned aerial vehicles (UAV) designed for remote monitoring (reconnaissance) of certain regions. A model that takes into account the UAV failure in performing a flight mission is considered. The numerical method and examples of solving problems stated are presented.     

Working processes in the solid-propellant low-temperature aerosol generator with an inert heatexchanger

Alignment charts that make it possible to select a standard size of inert heatexchanger structures with specified output characteristics and a developed scheme of the low-temperature aerosol generator are presented.     

Thermodynamic features of aircraft diagonal gas turbines

An effect of the Coriolis forces on the process of gas expansion in the turbine stage is considered. Expressions for efficiency with regard for the radial flow passage are derived. The calculation results and statistical data on the geometric parameters of diagonal stages are presented.     

Solving a plane problem of elasticity theory with the use of a hybrid FEM formulation

In the framework of a plane problem of elasticity theory in strength analysis based on the finite element method in the hybrid formulation, we suggest that the approximation of displacements and stresses be used as magnitudes of vector and tensor fields, respectively. The quadrilateral finite element, the displacements and stresses of which are accepted as nodal unknowns is proposed. The mixed Reissner functional is applied to form a finite element deformation matrix.     

Unsteady oscillation of a deformable airfoil section in incompressible flow

The unsteady aerodynamic loads (pressure increment and generalized forces) acting on a deformable thin airfoil section are determined for its arbitrary motion in the incompressible flow with transverse gusts. In this case, the exact Küssner solution in series is used for harmonic oscillation of an airfoil, in which the Theodorsen function is approximated by a sum of fractional functions with poles. In the time domain, these functions are replaced by the unknown functions that satisfy the one-type ordinary first order differential equations. The equations obtained are combined with the differential equations of the airfoil motion in the generalized coordinates and are used for analyzing the aeroelastic system stability and calculating its dynamic response to gust loads.     

A generalized mathematical model of magneto-inertial horizon-compass deviation

An approach and algorithms are proposed that make it possible to take into account an effect of magnetic interferences introduced by a mobile object, variation of its inclination angles and, hence, to improve precision of the magneto-inertial horizon-compass operation.     

Regional Centres for Space Science and Technology Education and ICG Information Centres affiliated to the United Nations

Based on resolutions of the United Nations General Assembly, Regional Centres for Space Science and Technology Education were established in India, Morocco, Nigeria, Brazil and Mexico. Simultaneously, education curricula were developed for the core disciplines of remote sensing, satellite communications, satellite meteorology, and space and atmospheric science. This paper provides a brief summary on the status of the operation of the regional centres with a view to use them as information centres of the International Committee on Global Navigation Satellite Systems (ICG), and draws attention to their educational activities.