Професор Ф.М. Левон. Життєвий і творчий шлях (до 75-річчя від дня народження)

The milestones of a course of life and scientific activity of the scientist-forester, the ecologist, the known specialist in the field of an amenity planting and an afforestation, professor F.M. Levon are elucidated.Висвітлено основні етапи життєвого шляху і наукову діяльність вченого-лісівника, еколога, знаного спеціаліста в галузі створення зелених насаджень в умовах урбогенного і техногенного середовища, професора Ф.М. Левона

Dynamics of ring dark solitons in Bose-Einstein condensates and nonlinear optics

Quasiparticle approach to dynamics of dark solitons is applied to the case of ring solitons. It is shown that the energy conservation law provides the effective equations of motion of ring dark solitons for general form of the nonlinear term in the generalized nonlinear Schroedinger or Gross-Pitaevskii equation. Analytical theory is illustrated by examples of dynamics of ring solitons in light beams propagating through a photorefractive medium and in non-uniform condensates confined in axially symmetric traps. Analytical results agree very well with the results of our numerical simulations.Comment: 10 pages, 4 figure

Condition for convective instability of dark solitons

Simple derivation of the condition for the transition point from absolute instability of plane dark solitons to their convective instability is suggested. It is shown that unstable wave packet expands with velocity equal to the minimal group velocity of the disturbance waves propagating along a dark soliton. The growth rate of the length of dark solitons generated by the flow of Bose-Einstein condensate past an obstacle is estimated. Analytical theory is confirmed by the results of numerical simulations

Multipoint Vernier VISAR Interferometer System for Measuring Mass Velocity in Shock Wave Experiments

AbstractThe results of development of a laser interferometer designed to measure the mass velocity of condensed substances in shock wave experiments in the field of high energy density physics are presented. The developed laser system allows measurements of the velocity of free surfaces of samples in shockwave experiments with accuracy no worse than 10 m/s for the entire range of velocities attained experimentally. The time resolution of measurements is limited by the response speed of the used PMTs and amounts to 2.5 ns

VUV spectral line emission measurements in the TCABR tokamak

The study of tokamak plasma light emissions in the vacuum ultraviolet (VUV) region is an important subject since many impurity spectral emissions are present in this region. These spectral emissions can be used to determine the plasma ion temperature and density from different species and spatial positions inside plasma according to their temperatures. We have analyzed VUV spectra from 500 Å to 3200 Å wavelength in the TCABR tokamak plasma including higher diffraction order emissions. There have been identified 37 first diffraction order emissions, resulting in 28 second diffraction order, 24 third diffraction order, and 7 fourth diffraction order lines. The emissions are from impurity species such as OII, OIII, OIV, OV, OVI, OVII, CII, CIII, CIV, NIII, NIV, and NV. All the spectra beyond 1900 Å are from higher diffraction order emissions, and possess much better spectral resolution. Each strong and isolated spectral line, as well as its higher diffraction order emissions suitable for plasma diagnostic is identified and discussed. Finally, an example of ion temperature determination using different diffraction order is presented.39227027

Diagnostics of evolution of risk collapse complications at student group with anomalous cardiovascular reaction

The description of investigation of predisposition to potential danger of collapse complications at 429 first-year students during physical training is presented using the analysis of pulse wave form. With the help of developed device the group of students with predisposition to risk of collapse complications during physical activity has been revealed. The results of clinical examination have confirmed the predisposition of the given group to risk of collapse complication

Model for tumour growth with treatment by continuous and pulsed chemotherapy

Peer reviewedPreprin