Dynamics in a noncommutative phase space

Dynamics has been generalized to a noncommutative phase space. The noncommuting phase space is taken to be invariant under the quantum group $GL_{q,p}(2)$. The $q$-deformed differential calculus on the phase space is formulated and using this, both the Hamiltonian and Lagrangian forms of dynamics have been constructed. In contrast to earlier forms of $q$-dynamics, our formalism has the advantage of preserving the conventional symmetries such as rotational or Lorentz invariance.Comment: LaTeX-twice, 16 page

On the Wigner function of the relativistic finite-difference oscillator in an external field

The phase-space representation for a relativistic linear oscillator in a homogeneous external field expressed through the finite-difference equation is constructed. Explicit expressions of the relativistic oscillator Wigner quasi-distribution function for the stationary states as well as of states of thermodynamical equilibrium are obtained and their correct limits are shown.Comment: 12 pages, 6 figures, IOP styled LaTeX, to be published in Journal of Physics

Control and measuring devices for controlling the temperature regime of the cooking cabinet

The article considers issues connected to natural lighting in rooms. The problem of lack of natural light in an apartment of a typical building of the M111-90 series in Belarus is described and ways of its solution are presented

Control and measuring devices for controlling the temperature regime of the cooking cabinet

The article considers issues connected to natural lighting in rooms. The problem of lack of natural light in an apartment of a typical building of the M111-90 series in Belarus is described and ways of its solution are presented

Global existence and finite time blow-up in a class of stochastic nonlinear wave equations

We consider a stochastic extension of a class of wave equations with nonlinear viscoelastic damping and nonlinear forcing. We show the global existence of the solution of the stochastic equation and, additionally, when the source term dominates the damping term and when the initial data are large enough, we show that the expected value of the L p norm of the solution, blows up in finite time. In the presence of noise, we extend the previously known range of initial data corresponding to blow-up. Furthermore we use a spectral stochastic Galerkin method to perform numerical simulations that verify certain special cases of our theoretical results

Pan-Eurasian Experiment (PEEX): Towards a holistic understanding of the feedbacks and interactions in the land-Atmosphere-ocean-society continuum in the northern Eurasian region

The northern Eurasian regions and Arctic Ocean will very likely undergo substantial changes during the next decades. The Arctic-boreal natural environments play a crucial role in the global climate via albedo change, carbon sources and sinks as well as atmospheric aerosol production from biogenic volatile organic compounds. Furthermore, it is expected that global trade activities, demographic movement, and use of natural resources will be increasing in the Arctic regions. There is a need for a novel research approach, which not only identifies and tackles the relevant multi-disciplinary research questions, but also is able to make a holistic system analysis of the expected feedbacks. In this paper, we introduce the research agenda of the Pan-Eurasian Experiment (PEEX), a multi-scale, multi-disciplinary and international program started in 2012 (https://www.atm.helsinki.fi/peex/). PEEX sets a research approach by which large-scale research topics are investigated from a system perspective and which aims to fill the key gaps in our understanding of the feedbacks and interactions between the land-Atmosphere-Aquatic-society continuum in the northern Eurasian region. We introduce here the state of the art for the key topics in the PEEX research agenda and present the future prospects of the research, which we see relevant in this context

Mathematical model and software for investigation of internal ballistic processes in high-speed projectile installations

This paper describes a software package that allows to explore the interior ballistics processes occurring in a shot scheme with bulk charges using propellant pasty substances at various loading schemes, etc. As a mathematical model, a model of a polydisperse mixture of non-deformable particles and a carrier gas phase is used in the quasi-one-dimensional approximation. Writing the equations of the mathematical model allows to use it to describe a broad class of interior ballistics processes. Features of the using approach are illustrated by calculating the ignition period for the charge of tubular propellant

Somatotopic features of the collagen skeleton of the knee meniscus in men

Relevance. The structural features of the collagen skeleton, including constitutional ones, suggest the ability of the menisci to withstand excessive mechanical stress and injury.Purpose – to study the differences in the collagen skeleton of the knee menisci in male corpses of different types of sexual dimorphism according to J. Tanner.Materials and methods. The menisci of the knee joints (medial and lateral) from the corpses of 84 men aged 22–74 years of different types of sexual dimorphism according to J. Tanner were studied. Microslides of the menisci at the level of the body, anterior and posterior horns, stained according to the method of K. Masson, were made. The location is described and the percentage of collagen fibers of the fibrous cartilage of the menisci of the knee joints with surrounding formations per unit area of unchanged cartilage tissue at the level of the horns and body of the menisci is calculated.Results. The collagen fibers of the body of both menisci of men are located in parallel, forming the central, upper and lower middle and superficial layers. In the horns, collagen fibers are located chaotically, which leads to “smoothing” of the boundaries. A minimal amount of collagen was found in the central layer of both horns and the body of the meniscus compared to the superficial layers. The maximum values of the percentage of collagen in the central layer are characteristic of the body, the minimum – for the posterior horn of the menisci. Low percentages of collagen in the dorsal horn are due to the andromorphic type.Conclusion. The andromorphic type of sexual dimorphism according to J. Tanner in men is a predisposition factor to damage to the menisci of the knee joints

Hydrodynamic bidimensional stability of detonation wave solutions for reactive mixtures

The structure of a planar detonation wave is analyzed for an Eulerian mixture of ideal gases undergoing the symmetric reversible explosive reaction A1 + A1 = A2 + A2. The chemical rate law is derived from the reactive Boltzmann equation, showing a detailed chemical kinetics in terms of a second-order reaction rate. The hydrodynamic bidimensional stability of the detonation wave is also investigated using a normal mode approach, when small time-space transverse disturbances affect the shock wave location. A suitable numerical technique is here proposed in order to solve the stability problem and numerical results are provided illustrating the detonation wave structure and its instability spectrum.The paper is partially supported by Brazilian Research Council (CNPq), by Italian Research Council GNFM-INdAM, and by Portuguese Funds of FCT, CMAT project UID/MAT/00013/2013

ON ONE APPROACH TO THE CALCULATION OF THE BITUMEN MELTING PROCESS

The paper presents a technique for numerical modeling of the process of heating bitumen with its transfer to a characteristic liquid state, when convective flows of the medium are observed. The mathematical model of the process is formulated on the basis of the two-phase Stefan problem with the use of equations that determine the free motion of particles in the melt. The calculation results and conclusions are presented.В работе представлена методика численного моделирования процесса разогрева битума с переводом его в характерное жидкое состояние, когда наблюдаются конвективные потоки среды. Математическая модель процесса сформулирована на основе двухфазной задачи Стефана с привлечением уравнений, определяющих свободное движение частиц в расплаве. Приведены результаты расчетов и выводы