“Ah, summer red, I would love you, if not for the heat, and dust, Yes mosquitoes, Yes flies”. And although the high poetry of the great poet little combined with the dry prosaic lines, technical articles, these words can be safely put as the epigraph to this material. To stop the change of seasons in nature is impossible, and every year we have a “happening” summer, and with it come the usual worries of relief and localization of negative emotions, invariably manifested in humans with the appearance of annoying flying insects — mosquitoes, flies and other midges. To protect yourself from them, in nature and even at home someone buys a mosquito net, others treat themselves and family members with special insect repelling creams and formulations. However, possessing the skills, you can build a simple circuit protection device against mosquitoes, operating by using of ultrasonic radiation. What is ultrasound?
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Overcoming water obstacles by troops in the course of warfare is still one of the most difficult tasks of engineering support of Special importance is its start — up phase, the crossing, that is, overcoming water obstacles with the battle, when the opposite Bank defended by the enemy the Crossing ends with the capture of the vanguard or the first echelon of the advancing troops of the bridgehead, eliminating the possibility of enemy direct fire of ferrying troops.
Since the profession of Aviator became popular, there was a need for a training aircraft They were needed for initial pilot training and for maintaining the necessary level of flight training of the personnel of combat units. Since the thirties of the XX century, a whole generation of Soviet pilots passed the initial training on a simple and reliable aircraft Po-2 For advanced training were used Yakovlevskaya UT-1 and UT-2. After the war, under the leadership of Alexander Yakovlev for this purpose has created the Yak-18 and Yak-11.
When carrying out installation work related to installation of structures on mortgages supporting parts of foundations, as a result of violation of technological process or as a result of its imperfections may be difficulties caused by irregularities in the supporting surfaces (local distortions, holes, etc exceeding permissible limits). Such situations often arise in the installation of industrial equipment, but such cases are not uncommon in everyday life. For example, the use of embedded items in the Foundation in the construction of different buildings on a country or a plot.
Many model airplanes-students dream to provide their own model gliders hooks for dynamic start. Designs that have already been published, quite complex for the manufacture of novice modelers.
Ministerial reshuffle in France in the 90-ies of the XIX century in the absence of common ideas in the creation of the Navy not only politicians, but also among experts has led to what could cause any mess of Sharp change of course has impact on all classes of ships, but the most affected was exactly cruiser.
Yes, this oven lay on the wood, and… motors that require repair. “Burn” them in her invited young innovators Omsk CHPP-4, participants NTTM-78. It is easy to imagine how much work and time consuming in the repair of electric motors, the extract from the grooves of the rotor and stator are tightly Packed windings with insulating filling. In furnace insulation under high temperature burns, its volume is reduced by more than a third, and the wire is easily removed.
