The paper provides an analysis of the principles of the multichannel protection system. The analysis showed that in order to solve the problem of ensuring secure communication with an external resource through public networks, it is advisable to use a multi-channel system with different channel capacities, while the main channel and spare channels that are connected to work when the main channel cannot handle all incoming applications with probability of 0.95. This model takes into account that the channels are filled hierarchically, and are freed up as the applications are processed.

Keywords: automated system, modeling, protection subsystem, queuing system, probabilistic assessment

At present an important role in solving energy conservation problem is assigned to thermal pumping plants (TPP). Using processes of evaporation and condensation of easily boiling liquid circulating in the system they extract low potential heat from environmental objects and provide heat supply for buildings, constructions, greenhousee and so on. Artificial sources of low potential heat for TPP of different capacity can be, for instance, ventilation air and exhaust gases, circulating and waste water,ground. Energy efficient reasonability of TPP use in the system of water disposal for the town of Novocherkassk in Rostov region is considered. Calculations indicate that there is a technical potential to replace a boiler house operating on expensive gas fuel and emissing into the atmospere more than 850 t of carbon dioxide - greenhouse gas - with ecologically clean TPP, one of which uses heat of waste water and the other - heat of ground.

Keywords: thermal pumping plant, renewable sources, energy conservation, evaporation, condensation, waste water, ground

  Prospects are discussed of interorbital transportation vehicles based on reusable space tugs with nuclear electric rocket propulsion for spacecraft delivering to the high orbits. The potential advantages of this kind of tugs are demonstrated comparing with the traditional spacecraft launch technologies. The issues of the nuclear interorbital tugs development are examined with the special attention towards the baseline information uncertainty, as well as of the nuclear space tugs ground processing considering requirements of the nuclear and radiation safety.

Keywords: Geostationary orbit, spacecraft, interorbital space tug, parametric optimization, radiation safety, upper stage, interorbital transportation means, nuclear electric rocket propulsion, power and propulsion system.