Optimization of building constructions on the basis of genetic algorithm

The technique of optimal design of bearing structures on the basis of genetic algorithm has been suggested. A design of steel frame with varying 9 parameters using the method of finite elements is considered as an example. The best variant corresponding to the volume minimum of the frame material is revealed

Optimization of building constructions on the basis of genetic algorithm

The technique of optimal design of bearing structures on the basis of genetic algorithm has been suggested. A design of steel frame with varying 9 parameters using the method of finite elements is considered as an example. The best variant corresponding to the volume minimum of the frame material is revealed

Obtekanie Krylovogo Profilia Pri Dokriticheskoi Skorosti Potoka

"The use of the linearized equations of Chaplygin to calculate the subsonic flow of a gas permits solving the problem of the flow about a wing profile for absence and presence of circulation. The solution is obtained in a practical convenient form that permits finding all the required magnitudes for the gas flow (lift, lift moment velocity distribution over the profile, and critical Mach number). This solution is not expressed in simple closed form; for a certain simplifying assumption, however, the equations of Chaplygin can be reduced to equations with constant coefficients, and solutions are obtained by using only the mathematical apparatus of the theory of functions of a complex variable" (p. 1)

Deposition of the low resistive ITO-films by means of reactive magnetron sputtering of the In/Sn target on the cold substrate

Detailed information on the deposition technology of the low-resistive ITO-films in oxygen-containing media by magnetron reactive sputtering from the In(90%)/Sn(10%) target on the cold substrate is given. Developed technology allows deposition ITO-films with sheet resistance transparency higher than 90%. Developed technology is notable for high reproducibility of results and is compatible with production technology of semiconductor devices of optoelectronics

Stages and Fracture Mechanisms of Lamellar Pearlite of 100-m-Long Differentially Hardened Rails Under Long-Term Operation Conditions

Using the methods of transmission electron microscopy, the carbide phase evolution in surface layers of the differentially quenched rails is studied after the passed tonnage of 691.8 million tons at the depth up to 10 mm along the central axis and fillet of rail head. The action of two mutual supplement mechanisms of steel carbide phase transformation in surface layers at rail operation is established: (1) cutting mechanism of cementite particles with the following departure in the volume of ferrite grains or plates (in pearlite structure); (2) cutting mechanism and following dissolution of cementite particles, transfer of carbon atoms on dislocations (in Cottrell atmospheres and dislocation cores), transfer of carbon atoms by moving dislocations into ferrite grains volume (or plates) with the following repeated formation of nanosized cementite particles. The first mechanism is accompanied by the change in linear sizes and morphology of carbide particles. Cementite element composition change is not essential. Carbide structure change can take place during the second mechanism

Distribution, resources, features of biology, and the first results of specialized fishery of shrimp <i>Pandalus goniurus</i> in the Tatar Strait

Shrimp Pandalus goniurus is poorly known in the Tatar Strait. Its distribution, state of stock, and features of biology are described on the data of 7 trawl surveys conducted by RV Buhoro in the western Tatar Strait in April-June 2009-2010 (227 trawls) and September-October 2011-2014 (589 trawls) and commercial catches obtained by fishing vessel Sovetskoye in May 2014 (50 trawls) and April 2015 (59 trawls). Horizontal opening of the scientific and commercial trawls was 16 and 35 m, respectively. About 14,000 individuals of the shrimp were subjected to biological analysis. P. goniurus was distributed along the whole continental coast of the strait northward from 47°20′ N and in spring concentrated at the depth from 50 to 120 m, rarely to 270-300 m, with single findings down to 340 m. Its stock fluctuated from 16 to 70 thousand t, on average 45,000 t (50-70 % within the territorial waters); possible annual catch was estimated as 5,000 t. Commercial fishery of this species was started in 2014 (mean CPUE 1.91 t/hour), the number of fishing vessels increased to 3 in 2015 (mean CPUE 3.26 t/hour, total landing 1160 t). The fishery is distinguished by easy hydroacoustic search of aggregations, long-time fishing within limited areas, high catches, including the catches in nighttime, and low bycatch. The highest concentration of P. goniurus was registered in April 2015: CPUE 11.86 t/hour, density 73.2 t/km2 or 10 ind./m2. Size-weight parameters of P. goniurus in the Tatar Strait were the best for all its populations: their average values in commercial catches in 2014/2015 were: carapace length 20.4/22.4 mm, individual weight 5.7/7.4 g or 165/116 ind./kg. Its larvae hatching was observed in April-May, mass post-hatching molt of females was supposedly in June-July and breeding molt and spawning - in September-October. First results of the fishery are analyzed, its prospects are estimated, and measures for its regulation are proposed