Mathematical model of steam generator feed system at power unit of nuclear plant

A mathematical model of a steam generator feed system at a power unit of a nuclear plant with variable values of transfer function coefficients is presented. The model is realized in the MATLAB/Simulink/Stateflow event-driven simulation.     

Production of Bronze-Steel Bimetallic Parts by Lost Foam Casting

Chemical and Petroleum Engineering - The process of interaction of a bronze insert placed in a lost foam mold with liquid steel filling this mold and thus producing a bimetallic part is...     

Rheological properties and similarity conditions in simulating the upsetting of a titanium alloy VT20 billet: I. Experimental results

The results of high-temperature tensile and compressive tests are used to analyze the effect of a mechanical deformation scheme and the ratio of the initial sizes of the specimens to be upset on the rheological properties of the VT20 titanium alloy.     

Coordination of arm movement during locomotion in Ophiuroidea

Ophiura Amphipholis kochii Lütken can move with any one of five arms directed forwards; therefore, each arm performs various functions during locomotion. The arm amputated together with the adjoining part of the central nervous ring is capable of complicated behaviour, particularly, of locomotion. Transection of the central nervous ring results in disturbances of the arms coordination. Experiments with amputation of a part of the arms showed that afferent signals from arms are important for determination of the leading arm and mode of locomotion. The experimental data suggest that each arm has an autonomous nervous centre, and coordinated activity of all arms is acheaved by an interaction of the nervous centres. The interaction results in function distribution among the arms and in synchronization of arm movements. The leading arm prevails, since the influences exerting by its centre determine activity of adjacent centres.     

Improvement of blast-furnace smelting at PAO Severstal’

In response to change in plant output and the hot-metal composition, unstable batch composition and characteristics, and increase in the recycled content, the maintenance of stable, economical, and highproductivity operation of the blast furnace shop at Cherepovets Metallurgical Works (PAO Severstal’) is of great importance. Particular attention focuses on increasing blast-furnace stability by improving the batch distribution within the furnace. The introduction of a blast-furnace technology with low slag yield (<250 kg/g of hot metal) is analyzed.     

Gregory G. Menshikov has turned 70

Reliable Computing -     

Re-operations after formerly performed suturing of the "silent" perforative duodenal ulcer

After the "silent" perforative duodenal ulcer closure the gap till the complications would occur, which need reoperation, by two times more than such period of time in patients with typical ulcer anamnesis, preceding the perforation. The reoperation causes are the recurrence (in 50.6% of observations), newly occurred ulcer (in 26.9%) or nonhealing of already existing (in 22.5%) duodenal ulcer. The reoperation method of choice is gastric resection according to Billroth-I in combination with truncal vagotomy in case of hypersecretory syndrome.