Influence of Wheel Blunting on the Machining Precision in CNC Plunge Grinding: Digital Twin Analysis

Russian Engineering Research - The machining precision in grinding a flexible shaft by sharp and blunt wheels is compared for a CNC system with a specified cycle of radial supply velocities. To...     

Optoviscosimetry of a Liquid Film by the Method of a Dispersed Magnetic Sublayer

A magnetooptical method of measurement of viscosity, which is based on recording the optical response (induced by the magnetic-field pulses) of a two-layer system resulting from the sedimentation of ferroparticles dispersed in the liquid under study, has been proposed. The procedure has been described and the results of measurement of the rheokinetics of a number of media, including polymer compositions formed into a thin film, in heating, evaporation, and polymerization have been presented.     

Upgrade of circulating water supply in glass production

The experience in the development and service of circulating water supply systems at glass factories is described, The reconstruction of such system has made it possible to decrease to one-tenth the consumption of freshwater.     

Training recurrent neurocontrollers for real-time applications.

In this paper, we introduce a new approach to train recurrent neurocontrollers for real-time applications. We begin with training a recurrent neurocontroller for robustness on high-fidelity models of physical systems. For training, we use a recently developed derivative-free Kalman filter method which we enhance for controller training. After training, we fix weights of our recurrent neurocontroller and deploy it in an embedded environment. Then, we carry out additional training of the neurocontroller by adapting in real time its internal state (short-term memory), rather than its weights (long-term memory). Such real-time training is done with a new combination of simultaneous perturbation stochastic approximation (SPSA) and adaptive critic. Our critic is also a recurrent neural network (RNN), and it is trained by stochastic meta-descent (SMD) for increased efficiency. Our approach is applied to two important practical problems, electronic throttle control and hybrid electric vehicle control, with apparent performance improvement.     

Effect of Quasi-Hydrostatic Compression on the Mechanical Properties of Ceramics in the ZrO2 + 3 MOL.% Y2O3 System

The effect of quasi-hydrostatic compression on the strength of ZrO₂ + 3 mol.% Y₂O₃ ceramic specimens of two series was studied. The series 1 ceramic was a powder commercially available from TOSOH Co. (Japan), with a density of 6.1 g/cm³, and the series 2 ceramic was a powder with a density of 5.9 g/cm³ prepared under laboratory conditions at the IPM Research Institute (National Academy of Sciences, Ukraine). The pressure range was up to 1.2 GPa, and the pressure-transmitting medium was a coarse-grained corundum powder. In the series 1 specimens, the strength increases with pressure over the entire pressure range (from 670 MPa to 1098 MPa at 1.2 GPa); in the series 2 specimens, the strength increases only to a pressure of 0.8 GPa (from 695 MPa to 828 MPa) and then, with further increase in pressure drops sharply to nearly zero (30 MPa at 1.2 GPa). It was proposed that the observed effect might be associated with a martensite transformation in the zone of structural imperfections (discontinuities). On reaching a critical value determined by the strength of the matrix, the martensite transformation becomes a cause of failure of the material.     

Morphological and structural features of polyacrylonitrile fibres spun by the dry-wet method

Conclusions -- A technological regime for the preparation of polyacrylonitrile fibres from binary and ternary copolymers has been chosen; these differ from known specimens in having a more uniform cross-sectional structure and a smoother elementary filament surface.-- A considerable difference in crystalline structure of fibres from binary and ternary copolymers which have been spun into a dimethyl sulfoxide—water bath has been shown.-- Fibres from the binary or ternary copolymer which have been spun into a precipitation bath having a large dimethyl sulfoxide content in water are characterized by a lower degree of swelling.-- Shrinkage of fibres from the binary copolymer in the temperature range 200–220°C is twice as small as the shrinkage of fibres from the ternary copolymer.Deceased.VNIIPV. Translated from Khimicheskie Volokna, No. 3, pp. 19–22, May–June, 1991.     

Swelling of steels and alloys irradiated in the BOR-60 reactor to a fluence of 1.1·1023 neutrons/cm2

Conclusions The structure created by preliminary treatment has a strong influence on the swelling, the nature of pore generation, the dislocation density, and the phase composition of 0Kh16N15M3B steel. The greatest reduction in swelling was produced by 20% cold deformation, which at a high dislocation density led to a sharp refinement of the pores and lamellar precipitations.The lamellar phases precipitated in steels of the Kh16N15 type during the irradiation after special alloying or preliminary treatment do not always determine the nature of the generation and growth of vacancy pores.At a temperature of 460 and 550°C the swelling of nickel is less by a factor of about 3, and the swelling of iron is less by a factor of about 10, than the swelling of austenized 0Kh16N15M3B steel.The least swelling was found in the Kh77TYu alloy (with 77% nickel), which before irradiation contained -phase pre-precipitations, whereas the swelling of alloys with 40 and 60% nickel is 100 times as great. From this it is clear that the nickel content is not the only factor determining the swelling.Journal version of a report delivered at the Conference on the Study of Reactor Materials (Alushta, 1978).Translated from Atomnaya Énergiya, Vol. 45, No. 6, pp. 433–439, December, 1978.