3,296 research outputs found
Effect of rhythmic photostimulation on monkeys with hyperkinesis of post-encephalitic genesis
In hyperkinetic monkeys a response opposite to that of healthy monkeys was observed during rhythmic photostimulation (frequency 3, 9, 18, 20, and 25/sec), i.e., the hyperkinesis disappeared. The significance of rhythmic excitatory cycles for interconnections between different brain structures is discussed
Circular photon drag effect in bulk tellurium
The circular photon drag effect is observed in a bulk semiconductor. The
photocurrent caused by a transfer of both translational and angular momenta of
light to charge carriers is detected in tellurium in the mid-infrared frequency
range. Dependencies of the photocurrent on the light polarization and on the
incidence angle agree with the symmetry analysis of the circular photon drag
effect. Microscopic models of the effect are developed for both intra- and
inter-subband optical absorption in the valence band of tellurium. The shift
contribution to the circular photon drag current is calculated. An observed
decrease of the circular photon drag current with increase of the photon energy
is explained by the theory for inter-subband optical transitions. Theoretical
estimates of the circular photon drag current agree with the experimental data.Comment: 8 pages, 4 figure
Exact relations for quantum-mechanical few-body and many-body problems with short-range interactions in two and three dimensions
We derive relations between various observables for N particles with
zero-range or short-range interactions, in continuous space or on a lattice, in
two or three dimensions, in an arbitrary external potential. Some of our
results generalise known relations between large-momentum behavior of the
momentum distribution, short-distance behavior of the pair correlation function
and of the one-body density matrix, derivative of the energy with respect to
the scattering length or to time, and the norm of the regular part of the
wavefunction; in the case of finite-range interactions, the interaction energy
is also related to dE/da. The expression relating the energy to a functional of
the momentum distribution is also generalised, and is found to break down for
Efimov states with zero-range interactions, due to a subleading oscillating
tail in the momentum distribution. We also obtain new expressions for the
derivative of the energy of a universal state with respect to the effective
range, the derivative of the energy of an efimovian state with respect to the
three-body parameter, and the second order derivative of the energy with
respect to the inverse (or the logarithm in the two-dimensional case) of the
scattering length. The latter is negative at fixed entropy. We use exact
relations to compute corrections to exactly solvable three-body problems and
find agreement with available numerics. For the unitary gas, we compare exact
relations to existing fixed-node Monte-Carlo data, and we test, with existing
Quantum Monte Carlo results on different finite range models, our prediction
that the leading deviation of the critical temperature from its zero range
value is linear in the interaction effective range r_e with a model independent
numerical coefficient.Comment: 51 pages, 5 figures. Split into three articles: Phys. Rev. A 83,
063614 (2011) [arXiv:1103.5157]; Phys. Rev. A 86, 013626 (2012)
[arXiv:1204.3204]; Phys. Rev. A 86, 053633 (2012) [ arXiv:1210.1784
The system of human resource development in energy saving in the Ural region
A system of education in the field of energy saving has been developed, built and successfully used for a number of years in the Ural region. In the Ural Federal University (UrFU) the "Energy Saving" Department and Regional Learning and Teaching Centre were created in 1999. At the present time more than 2000 senior students of ten institutes and of a number of UrFU territorial branches listen to lectures and study energy saving and energy efficiency issues at the practical studies yearly at the "Energy Saving" Department. In teaching the above mentioned disciplines a problematic-topical approach is used. It promotes forming a high level of concern and motivation among students to study and master the bases of theoretical and practical activity, enabling them to get the most actual and reliable information. Employees of the department have prepared and published a considerable volume of courseware and scientific-andtechnological literature on the problems of energy saving and raising efficiency of energy usage, forming an academic system, which includes different levels and types of knowledge, methods of educating. Masters' preparing has been started together with the department "Atomic power stations and renewable energy sources" with the deepened studying energy saving and energy efficiency issues. Taking this experience into account, an education standard of UrFU "Energy saving and energy efficiency raising in industry and budget sphere". Thus, a complex approach for creating and constantly improving the system of energy saving specialists' preparation has been realized and is being developed in the territory of the Ural region. © 2014 WIT Press.International Journal of Safety and Security Engineering;International Journal of Sustainable Development and Planning;WIT Transactions on Ecology and the Environmen
Global in Time Solutions to Kolmogorov-Feller Pseudodifferential Equations with Small Parameter
The goal in this paper is to demonstrate a new method for constructing
global-in-time approximate (asymptotic) solutions of (pseudodifferential)
parabolic equations with a small parameter. We show that, in the leading term,
such a solution can be constructed by using characteristics, more precisely, by
using solutions of the corresponding Hamiltonian system and without using any
integral representation. For completeness, we also briefly describe the
well-known scheme developed by V.P.Maslov for constructing global-in-time
solutions.Comment: 27 page
Method for direct identification of optimum modal values of dynamical systems
The synthesis method of a dynamic system by successive solutions of two systems of algebraic equations, variables that are characteristic polynomial coefficients and mechanical parameters of the system
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