Correlation between General Education and Vocational Training: Development of Theory and Practice in History and Major Trends of Contemporary Research in Western Europe, USA, Australia

The article gives a brief review of the development of the theory and practice of correlation between general education and vocational training and provides an overview of the major trends in the contemporary research in this sphere in such countries as Germany, France, USA, Australia and others. The underlying reason for this survey is the necessity to enhance training of craft and trade workers in Russia both in general and vocational subjects taking into account the experience of other countriesВ статье кратко рассматривается развитие теории и практики взаимосвязи общеобразовательной и профессиональной подготовки, а также описываются основные направления современных исследований в данной сфере в таких странах как Германия, Франция, США, Австралия и др. Основным мотивом проведения данного исследования является необходимость улучшить подготовку по специальностям ремесленного профиля в России по предметам общеобразовательной и профессиональной подготовки с учетом опыта других стра

Ladder of Eckhaus instabilities and parametric conversion in chi(2) microresonators

Low loss microresonators have revolutionised nonlinear and quantum optics over the past decade. In particular, microresonators with the second order, chi(2), nonlinearity have the advantages of broad spectral tunability and low power frequency conversion. Recent observations have highlighted that the parametric frequency conversion in chi(2) microresonators is accompanied by stepwise changes in the signal and idler frequencies. Therefore, a better understanding of the mechanisms and development of the theory underpinning this behaviour is timely. Here, we report that the stepwise frequency conversion originates from the discrete sequence of the so-called Eckhaus instabilities. After discovering these instabilities in fluid dynamics in the 1960s, they have become a broadly spread interdisciplinary concept. Now, we demonstrate that the Eckhaus mechanism also underpins the ladder-like structure of the frequency tuning curves in chi(2) microresonators.Comment: 10 pages, 5 figure

Efficient mass and stiffness matrix assembly via weighted Gaussian quadrature rules for B-splines

Calabr{\`o} et al. [10] changed the paradigm of the mass and stiffness computation from the traditional element-wise assembly to a row-wise concept, showing that the latter one offers integration that may be orders of magnitude faster. Considering a B-spline basis function as a non-negative measure, each mass matrix row is integrated by its own quadrature rule with respect to that measure. Each rule is easy to compute as it leads to a linear system of equations, however, the quadrature rules are of the Newton-Cotes type, that is, they require a number of quadrature points that is equal to the dimension of the spline space. In this work, we propose weighted quadrature rules of Gaussian type which require the minimum number of quadrature points while guaranteeing exactness of integration with respect to the weight function. The weighted Gaussian rules arise as solutions of non-linear systems of equations. We derive rules for the mass and stiffness matrices for uniform $C^1$ quadratic and $C^2$ cubic isogeometric discretizations. In each parameter direction, our rules require locally only $p+1$ quadrature points, $p$ being the polynomial degree. While the nodes cannot be reused for various weight functions as in [10], the computational cost of the mass and stiffness matrix assembly is comparable.RYC-2017-2264

Soliton metacrystals: topology and chirality

Designing metamaterials with the required band structure, topology and chirality using nano-fabrication technology revolutionises modern science and impacts daily life. The approach of this work is, however, different. We take a periodic sequence, i.e., metacrystal, of the dissipative optical solitons rotating in a single ring microresonator and demonstrate its properties as of the electromagnetic metamaterial acting in the radio to terahertz frequency range. The metacrystal unit cell consists of the bound pair of solitons, and the distance between them is used as a control parameter. We are reporting the soliton metacrystal band structure and its topological properties. The latter is confirmed by the existence of the $\pi$ steps experienced by the crystal phonons' geometrical (Zak) phase. Furthermore, we found the phononic edge states in the metacrystals with defects made by removing several solitons. Optical frequency combs corresponding to the soliton metacrystals reveal the spectral butterfly pattern serving as a signature of the spatio-temporal chirality and bearing a resemblance to the butterfly wings illustrating natural occurrences of chirality.Comment: 11 pages with an interesting Methods section. Title of the published version has been changed to "Topological soliton metacrystals

Walk-off induced dissipative breathers and dissipative breather gas in microresonators

Dissipative solitons in optical microcavities have attracted significant attention in recent years due to their direct association with the generation of optical frequency combs. Here, we address the problem of dissipative soliton breathers in a microresonator with second-order nonlinearity, operating at the exact phase-matching for efficient second-harmonic generation. We elucidate the vital role played by the group velocity difference between the first and second harmonic pulses for the breather existence. We report the dissipative breather gas phenomenon, when multiple breathers propagate randomly in the resonator and collide nearly elastically. Finally, when the breather gas reaches an out-of-equilibrium statistical stationarity, we show how the velocity locking between first and second harmonic is still preserved, naming such phenomena turbulence locking.Comment: 10 pages, 10 figure

Experience in modelling a curriculum based on the project approach

The authors describe their experience in modelling a curriculum while developing a bachelor education program. The curriculum contains modules each of which has its own goals and intermediate results. The development of an education program is considered as a project activityОписывается опыт моделирования учебного плана в рамках разработки основной профессиональной образовательной программы бакалавриата. Учебный план состоит из модулей, каждый из которых имеет свои целевые ориентиры и промежуточные результаты. Разработка образовательной программы рассматривается с точки зрения проектной деятельност

Universal threshold and Arnold tongues in Kerr ring microresonators

We report that an instability boundary of a single-mode state in Kerr ring microresonators with ultrahigh quality factors breaks the parameter space span by the pump laser power and frequency into a sequence of narrow in frequency and broad in power resonance domains - Arnold tongues. Arnold resonances are located between the Lugiato-Lefever (lower) and universal (higher) thresholds. Pump power estimates corresponding to the universal threshold are elaborated in details. RF-spectra generated within the tongues reveal a transition between the repetition-rate locked and unlocked regimes of the side-band generation.Comment: 6 page