Search results for "classical"
showing 10 items of 2294 documents
Formation of dislocation patterns: Computer simulations
1996
Dislocations patterns have been extensively studied by means of TEM. In parallel, theoretical approaches have been developed by using two methods; reaction diffusion schemes and computer simulation models. This distinction is not rigid since some computer models include the former approach in their evolution equations. Independently from the difficulties each approach presents in formulating the collective behavior of dislocations, the aim of these studies is to exhibit simple dislocation patterns as persistent slip bands and/or cellular organization. In this context, computer simulations brought a methodology which undoubtedly is a complement to the existing approaches for dislocations. Ne…
A numerical assessment of the free energy function for fractional-order relaxation
2014
In this paper a novel method based on complex eigenanalysis in the state variables domain is proposed to uncouple the set of rational order fractional differential equations governing the dynamics of multi-degree-of-freedom system. The traditional complex eigenanalysis is appropriately modified to be applicable to the coupled fractional differential equations. This is done by expanding the dimension of the problem and solving the system in the state variable domain. Examples of applications are given pertaining to multi-degree-of-freedom systems under both deterministic and stochastic loads.
A nonlocal strain gradient plasticity theory for finite deformations
2009
Abstract Strain gradient plasticity for finite deformations is addressed within the framework of nonlocal continuum thermodynamics, featured by the concepts of (nonlocality) energy residual and globally simple material. The plastic strain gradient is assumed to be physically meaningful in the domain of particle isoclinic configurations (with the director vector triad constant both in space and time), whereas the objective notion of corotational gradient makes it possible to compute the plastic strain gradient in any domain of particle intermediate configurations. A phenomenological elastic–plastic constitutive model is presented, with mixed kinematic/isotropic hardening laws in the form of …
LU Filoloģijas un filozofijas fakultātes klasiskās filoloģijas studenta Jāņa Gefkina (1911-1938) izvadīšana Rīgas Meža kapos
1938
The coffin of Jānis Gefkins (1911-1938), a graduate of Riga State Gymnasium No.1, student of classical philology at the Faculty of Philology and Philosophy of the University of Latvia and member of the Latvian student fraternity Fraternitas Lettica. PHOTO 2 - being taken from the chapel to his burial place in Riga Forest Cemetery in May 1938. PHOTO 2 - The Honour Guard of the Latvian student fraternity Fraternitas Lettica mournfully attends the funeral of their deceased member. PHOTO 3 - The honour guard of the Latvian student fraternity Fraternitas Lettica mournfully accompanies its deceased member to his burial place in the Riga Forest Cemetery.
LU Filoloģijas un filozofijas fakultātes klasiskās filoloģijas students Jānis Gefkins (1911-1938)
1938
Jānis Gefkins (1911-1938), a graduate of Riga State Gymnasium No.1, student of classical philology at the Faculty of Philology and Philosophy of the University of Latvia and member of the Latvian student fraternity Fraternitas Lettica, passed away at the age of 27.
Human Soul, Body and Life Horizons
2013
Phenomenology of life develops an essential transformation of the positioning of life, human being, soul and life horizons. Human soul reflects the passions of the earth and of the skies. There are two directions characteristic for the soul – upward and downward. Life horizons are closely connected with life forms, styles of living. It has been described in rather different cultures including post-modern culture. This paper deals with A.-T. Tymieniecka’s ideas about the New Enlightenment and critique of too narrow an explanation of human subjectivity and body and discusses the need for balance between soul’s directions and decreasing of materialistic, consumerism life form, orientations to …
From microscopic to macroscopic description of Josephson dynamics in one-dimensional arrays of weakly-coupled superconducting islands
2015
Abstract By starting from a microscopic quantum mechanical description of Josephson dynamics of a one-dimensional array of N coupled superconductors, we obtain a set of linear differential equations for the system order parameter and for additional macroscopic physical quantities. With opportune considerations, we adapt this description to two coupled superconductors, obtaining the celebrated Feynman model for Josephson junctions. These results confirm the correspondence between the microscopic picture and the semi-classical Ohta’s model adopted in describing the superconducting phase dynamics in multi-barrier Josephson junctions.
Unified description of 2+_1 states within the deformed quasiparticle random-phase approximation
2013
We describe low-lying collective states in deformed even-even nuclei within a deformed quasiparticle random-phase approximation (dQRPA) by using a single-particle basis with good angular momentum. The statistical factors, accounting for the level occupancy, appear in the dQRPA in a natural way as rotation coefficients that take the intrinsic system to the laboratory system. We have used our model by performing a systematic analysis of E2 transitions from the first ${2}^{+}$ state to the ground state for all superfluid nuclei in the range $50lZ\ensuremath{\le}100$ by using a common charge polarization parameter $\ensuremath{\chi}=0.2$. In spite of its similarity to the QRPA, this method is a…
Thermodynamical derivation of a hydrodynamical model of inhomogeneous superfluid turbulence
2007
In this paper, we build up a thermodynamical model of inhomogeneous superfluid turbulence to describe vortex diffusion in inhomogeneous turbulent tangles, and a coupling between second sound and vortex-density waves. The theory chooses as fundamental fields the density, the velocity, the energy density, the heat flux, and the averaged vortex line length per unit volume. The restrictions on the constitutive quantities are deduced from the entropy principle, using the Liu method of Lagrange multipliers. Field equations are written and the wave propagation is studied with the aim to describe the mutual interactions between the second sound and the vortex tangle.