A discrete space-time structure is proposed. The light speed invariant is derived as a natural consequence of the space-time lattice structure constant.

By means of a compound magnetic liquid -non-magnetic conductive inclusions, a new magnetofluidic media has been derived. The model of nano- and mesoscopic harmonic oscillators lattice structure is given. A magnetofluidic tunable acoustical filter is described.

The purpose of the paper is to describe an internal effect in a magnetofluidic media. An interesting effect is that of internal rotation of the nonmagnetic component. To avoid the sedimentation of composites in the terrestrial experiment, magnetic fields with gradient were needed to create the opposite force to gravity. In microgravity, the nonmagnetic solid component of the three-phase liquid needs no more magnetic gradient stabilization. The terrestrial

The purpose of the present paper is to introduce and describe some effects and possible utilization of magnetic fluid composites (MFC) for space onboard applications. The paper presents results suggesting possible applications of the magnetofluidic composites in space onboard technologies, in particular for sensors, actuators, and thermal transfer

The problem of attitude active control of one body by the command on the other body of the system is presented. In the case of the system of two tethered bodies the motion of rotation with respect to the mass center for the principal body is commanded by a torque in articulation which is applied to modify the relative attitude of the secondary body. In the case of two tethered bodies, the command torque on the principal body can be applied by the

Paths on the R3 real Euclidean manifols are define das 2-dimensional simplicial strips which are orbits of the action of a discrete one-parameter group. It is proven that there exists at least one embedding of R3 in the free Z-module generated by the S2(x0) sphere. The speed is defined as the simplicial derivative of the path. If mass is attached to the simplex, the free Lagrangian is proportional to the width of the path. In the continuum limit,

Two types of complex magnetizable media are considered in this work: a) magnetic liquids (ferrofluids) with deformable nonmagnetic inclusions (gas bubbles) and b) magnetic liquids with solid inclusions in the micrometer range. In both cases the behaviour of these composite fluid systems is strongly influenced by an applied magnetic field, but also by gravitational forces (e.g. lifting the bubbles and producing the sedimentation of heavier solid particles

The paths over a real Euclidean manifold are realised as 2-dimensional simplicial complexes. A surface proportional action is constructed. The relativistic free action on a (2+1) manifold is recovered in the continuum limit

The paper describes an experimental form of multidisciplinary postgraduate training in space science and technology, developed under the auspices of the Romanian Space Agency in the period 1994 - 1996. This specific form of training is recommended for developing countries

A small unmanned aircraft has been developed to experiment and teach a class of space science and technology applications. The vehicle, a lenticular aerodyne, is equipped to perform training in remote sensing, communications, attitude control and navigation. The main advantage of this system consists in the reduced period of time necessary to understand and to adjust the phases of a mission, with low costs.