4,011 research outputs found
Regla formal de justicia, valores y principios
SUMARIO: 1. Racionalidad y regla formal de justicia. 2. Las diferencias estructurales entre normas y principios. 3. Clases de principios. 4. Funciones de los principios. 5. Principios y racionalidad material del Derecho.Publicad
-particle sigma model: Momentum-space quantization of a particle on the sphere
We perform the momentum-space quantization of a spin-less particle moving on
the group manifold, that is, the three-dimensional sphere , by
using a non-canonical method entirely based on symmetry grounds. To achieve
this task, non-standard (contact) symmetries are required as already shown in a
previous article where the configuration-space quantization was given. The
Hilbert space in the momentum space representation turns out to be made of a
subset of (oscillatory) solutions of the Helmholtz equation in four dimensions.
The most relevant result is the fact that both the scalar product and the
generalized Fourier transform between configuration and momentum spaces deviate
notably from the naively expected expressions, the former exhibiting now a
non-trivial kernel, under a double integral, traced back to the non-trivial
topology of the phase space, even though the momentum space as such is flat. In
addition, momentum space itself appears directly as the carrier space of an
irreducible representation of the symmetry group, and the Fourier transform as
the unitary equivalence between two unitary irreducible representations.Comment: 29 pages, 3 figure
An experimental course on digital communications
In this paper a laboratory course on digital communications is presented. This course has been designed for medium degree professionals in the telecommunications field, and it is based on training equipment developed to change the usual theoretical classrooms for laboratory seminars.Peer ReviewedPostprint (published version
Feasibility and reliability of a Physical Fitness test battery in individuals with Down Syndrome
Background: Down syndrome (DS) is a genetic disorder that occurs because of an abnormal
division between cells that results in an extra copy of chromosome 21. Some studies show that
physical exercise in people with DS increases some cognitive capacities, such as memory, and improves
the quality of life. Aim: The main aim of this study was to perform an analysis of the reliability
and feasibility of the SAMU-Disability Fitness (DISFIT) battery in adults with DS. Methods: A
cross-sectional study with a test–retest design was performed in a maximum interval of 2 weeks in
37 subjects (11 women and 26 men) aged between 21 and 58 years old with DS. Eight field-based
fitness tests were proposed to assess the physical fitness (PF) of adults with DS: Body Mass Index
(BMI), Waist Circumference (WC), the Timed Up and Go test (TUG), the Deep Trunk Flexibility test
(DTF), the Hand Grip test (HG), the Timed Stand Test (TST), the 30-s Sit-Up (SUP) and the 6-Min
Walk Test (6MWT). Results: The intra-class correlation coefficient (ICC) in all the tests was good
and high (>0.80), except for the 6MWT, whose reliability was fair. Conclusion: The SAMU-DISFIT
battery is a reliable and feasible physical fitness battery which has been created with the purpose
of establishing tests which measure the four basic components of PF (flexibility, cardiorespiratory
fitness, musculoskeletal fitness and motor fitness) in adults with D
Coherent States for infinite homogeneous waveguide arrays
Perelomov coherent states for equally spaced, infinite homogeneous waveguide
arrays with Euclidean E(2) symmetry are defined, and new resolutions of the identity
are constructed in Cartesian and polar coordinates. The key point to construct these
resolutions of the identity is the fact that coherent states satisfy Helmholtz equation
(in coherent states labels) an thus a non-local scalar product with a convolution
kernel can be introduced which is invariant under the Euclidean group. It is also
shown that these coherent states for the Eucliean E(2) group have a simple and
natural physical realization in these waveguide arrays.Spanish MICINN through the project PGC2018-097831-B-I00 and Junta de Andalucı́a through the project FEDER/UJA-1381026
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