Checking Combinational Circuits by the Method of Logic Complement

Design of fully self-testing combinational circuits was considered. A theorem defining the conditions for guaranteed logic complement-based design of fully self-testing circuit was proved. Examples were presented.__________Translated from Avtomatika i Telemekhanika, No. 8, 2005, pp. 161–172.Original Russian Text Copyright © 2005 by Goessel, Morozov, V. Sapozhnikov, Vl. Sapozhnikov.     

Rames ferroviaires frigorifiques pour poissons vivantsRefrigerated rail wagons for transporting live fish

In the USSR a substantial quantity of live fish is transported by rail, the wagons being equipped with special refrigerating systems to maintain the fish in satisfactory condition.Complete trains are now in use, with one service wagon providing power to one, two or three wagons, each fitted with two tanks which contain 17 tonnes of fish. The chilled water in the tanks is aerated and agitated and there is special equipment to dispose of the CO₂, foam and waste matter.The paper describes the transport equipment and the results of measurements carried out on some trial runs. The installation can maintain a water temperature of 2°C and control the oxygen level at 4 mg l^?1, even with a full load of fish.     

Metalorganic vapour phase epitaxy of GaAs/AlGaAs nanoheterostructures for a quantum cascade laser

Short-period GaAs/AlGaAs superlattices, an active region, and a quantum cascade laser heterostructure have been grown by metalorganic vapor phase epitaxy, and their characteristics have been studied by high-resolution X-ray diffraction, transmission electron microscopy, and photoluminescence spectroscopy. The heterostructures have been used to produce quantum cascade lasers emitting near 10 μm. Their output pulse power at 77 K is above 200 mW.     

The calibration of gradient heat flux sensors

Test benches for calibrating heat flux sensors at temperatures of 500–1000 K are described, and the results of such calibrations are presented.     

The effect of surface waves on the interaction of incident particles with a solid surface

The incidence of two particles onto a thin solid plate has been studied by means of computer simulation. The influence of the impact-excited waves on the particle-surface interaction is considered. The waves excited in the target plate produce a significant change in the surface response dynamics. The distribution of surface damage and plastic strain generated by the incident particles is analyzed, and it is established that this distribution is correlated with the surface wave structure.