76 research outputs found
Sunspot waves and flare energy release
We address a possibility of the flare process initiation and further
maintenance of its energy release due to a transformation of sunspot
longitudinal waves into transverse magnetic loop oscillations with initiation
of reconnection. This leads to heating maintaining after the energy release
peak and formation of a flat stage on the X-ray profile. We applied the
time-distance plots and pixel wavelet filtration (PWF) methods to obtain
spatio-temporal distribution of wave power variations in SDO/AIA data. To find
magnetic waveguides, we used magnetic field extrapolation of SDO/HMI
magnetograms. The propagation velocity of wave fronts was measured from their
spatial locations at specific times. In correlation curves of the 17 GHz (NoRH)
radio emission we found a monotonous energy amplification of 3-min waves in the
sunspot umbra before the 2012 June 7 flare. This dynamics agrees with an
increase in the wave-train length in coronal loops (SDO/AIA, 171 {\AA})
reaching the maximum 30 minutes prior to the flare onset. A peculiarity of this
flare time profile in soft X-rays (RHESSI, 3-25 keV) is maintaining the
constant level of the flare emission for 10 minutes after the short impulse
phase, which indicates at the energy release continuation. Throughout this
time, we found 30-sec period transverse oscillations of the flare loop in the
radio-frequency range (NoRH, 17 GHz). This periodicity is apparently related to
the transformation of propagating longitudinal 3-min waves from the sunspot
into the loop transverse oscillations. The magnetic field extrapolation showed
the existence of the magnetic waveguide (loop) connecting the sunspot with the
energy release region. A flare loop heating can be caused by the interaction
(reconnections) of this transversally oscillating waveguide with the underlying
twisted loops.Comment: 7 pages, 9 figure
Methodology development for the sustainability process assessment of sheet metal forming of complex-shaped products
Β© Published under licence by IOP Publishing Ltd. A methodology was developed for automated assessment of the reliability of the process of sheet metal forming process to reduce the defects in complex components manufacture. The article identifies the range of allowable values of the stamp parameters to obtain defect-free punching of spars trucks
Aspects of a healthy lifestyle
A healthy lifestyle includes not only sports and limit yourself from bad habits, but many another aspects. We consider the most important criteria of the leading of a healthy lifestyle, such as elaborated regime of the day, healthy sleep, proper nutrition, personal hygiene and active life in this project. The main thing in a healthy way of life is an active creation of health, including all of its componentsΠΠ΄ΠΎΡΠΎΠ²ΡΠΉ ΠΎΠ±ΡΠ°Π· ΠΆΠΈΠ·Π½ΠΈ ΠΏΡΠ΅Π΄ΠΏΠΎΠ»Π°Π³Π°Π΅Ρ Π½Π΅ ΡΠΎΠ»ΡΠΊΠΎ Π·Π°Π½ΡΡΠΈΠ΅ ΡΠΏΠΎΡΡΠΎΠΌ ΠΈ ΠΎΠ³ΡΠ°Π½ΠΈΡΠ΅Π½ΠΈΠ΅ ΡΠ΅Π±Ρ ΠΎΡ Π²ΡΠ΅Π΄Π½ΡΡ
ΠΏΡΠΈΠ²ΡΡΠ΅ΠΊ, Π½ΠΎ Π΅ΡΠ΅ ΠΌΠ½ΠΎΠΆΠ΅ΡΡΠ²ΠΎ Π°ΡΠΏΠ΅ΠΊΡΠΎΠ². Π Π΄Π°Π½Π½ΠΎΠΉ ΡΠ°Π±ΠΎΡΠ΅ ΠΌΡ ΡΠ°ΡΡΠΌΠΎΡΡΠΈΠΌ ΡΠ°ΠΌΡΠ΅ Π²Π°ΠΆΠ½ΡΠ΅ ΠΊΡΠΈΡΠ΅ΡΠΈΠΈΠ²Π΅Π΄Π΅Π½ΠΈΡ Π·Π΄ΠΎΡΠΎΠ²ΠΎΠ³ΠΎ ΠΎΠ±ΡΠ°Π·Π° ΠΆΠΈΠ·Π½ΠΈ, ΡΠ°ΠΊΠΈΠ΅ ΠΊΠ°ΠΊ Π²ΡΡΠ°Π±ΠΎΡΠ°Π½Π½ΡΠΉ ΡΠ΅ΠΆΠΈΠΌ Π΄Π½Ρ, Π·Π΄ΠΎΡΠΎΠ²ΡΠΉ ΡΠΎΠ½, ΠΏΡΠ°Π²ΠΈΠ»ΡΠ½ΠΎΠ΅ ΠΏΠΈΡΠ°Π½ΠΈΠ΅, Π»ΠΈΡΠ½Π°Ρ Π³ΠΈΠ³ΠΈΠ΅Π½Π° ΠΈ ΠΏΠΎΠ΄Π²ΠΈΠΆΠ½ΡΠΉ ΠΎΠ±ΡΠ°Π· ΠΆΠΈΠ·Π½ΠΈ.ΠΠ»Π°Π²Π½ΠΎΠ΅ Π² Π·Π΄ΠΎΡΠΎΠ²ΠΎΠΌ ΠΎΠ±ΡΠ°Π·Π΅ ΠΆΠΈΠ·Π½ΠΈ β ΡΡΠΎ Π°ΠΊΡΠΈΠ²Π½ΠΎΠ΅ ΡΠ²ΠΎΡΠ΅Π½ΠΈΠ΅ Π·Π΄ΠΎΡΠΎΠ²ΡΡ, Π²ΠΊΠ»ΡΡΠ°Ρ Π²ΡΠ΅ Π΅Π³ΠΎ ΠΊΠΎΠΌΠΏΠΎΠ½Π΅Π½Ρ
Ultrasound in the manufacture of medical instruments
Β© Published under licence by IOP Publishing Ltd. The article contains information on the properties and possibilities of ultrasonic oscillations of high intensity, the features of the application of ultrasonic vibrations for the intensification of processes occurring in liquid, solid, gaseous media, polymeric materials, as applied to solving problems in the chemical, biotechnological, food industries and related industries. The methods of using ultrasound for cleaning parts on grinding and polishing operations, which are primarily intended for use in the manufacture of medical instruments, are described in more details
Automated Generation of Rational Sheet Metal Forming Technology Variants at Process Engineering Stage
Β© 2017 The Authors. Published by Elsevier Ltd. The procedure of automated process reliability evaluation was developed in order to prevent recurrent defects in parts manufactured by die stamping. The procedure is based on the analysis of such factors as part design, material, its mechanical and physical properties; equipment parameters, tool performance, etc. The list of reliability factors may vary according to a type of operation as deformation process is different for each group of operations. The adjustment of stamping process reliability performance prevents any defects emerging during production of critical parts as early as the PPE stage. The automated control system for IE design at the PPE stage provides better part quality and lower production expenses thanks to IP reliability
An expert system for ensuring the reliability of the technological process of cold sheet metal forming
In order to exclude periodic defects in the parts manufacturing obtained by cold sheet metal forming a method of automated estimation of technological process reliability was developed. The technique is based on the analysis of reliability factors: detail construction, material, mechanical and physical requirements; hardware settings, tool characteristics, etc. In the work the expert system is presented based on a statistical accumulation of the knowledge of the operator (technologist) and decisions of control algorithms
Imrovement of the cold forming technology of the parts such as longeron
Β© Published under licence by IOP Publishing Ltd. As a result of modeling in LS-PREPOST preprocessor of the program LS-DYNA a range of radii of curvature edge transition matrix (27,5 Β°β€ R β€ 48 Β°) is obtained, which allows to produce defect-free stamping slots for longeron shock absorbers of tractors KAMAZ-5460
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