3,866 research outputs found
Anderson Localization in Disordered Vibrating Rods
We study, both experimentally and numerically, the Anderson localization
phenomenon in torsional waves of a disordered elastic rod, which consists of a
cylinder with randomly spaced notches. We find that the normal-mode wave
amplitudes are exponentially localized as occurs in disordered solids. The
localization length is measured using these wave amplitudes and it is shown to
decrease as a function of frequency. The normal-mode spectrum is also measured
as well as computed, so its level statistics can be analyzed. Fitting the
nearest-neighbor spacing distribution a level repulsion parameter is defined
that also varies with frequency. The localization length can then be expressed
as a function of the repulsion parameter. There exists a range in which the
localization length is a linear function of the repulsion parameter, which is
consistent with Random Matrix Theory. However, at low values of the repulsion
parameter the linear dependence does not hold.Comment: 10 pages, 6 figure
Epistemología y política en el discurso pedagógico
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Anthropometric Profile in Different Event Categories of Acrobatic Gymnastics
There is a specific anthropometric profile for each sport, which may be differentiated even in relation to the position, role or event category within each sport discipline. However, there are few studies on acrobatic gymnastics, and the goal of this work was to determine the anthropometric profile depending on the event category, as well as factors that predisposed to performance in these categories. The sample consisted of 150 gymnasts from Spain, divided into 8 groups according to the event category and the role played. The kinanthropometric measurements were taken through the procedures established by the International Society for the Advancement of Kineantropometry. The anthropometric characteristics, including body mass index, somatotype, body composition and proportionality using the Phantom stratagem were analyzed, and the results obtained from the different groups were compared. A regression analysis was performed with particular groups of gymnasts. No significant differences (p < 0.05) were observed between groups of female tops or male bases, although differences were found between female group bases and female pair bases. It could be suggested that higher values of body height, sitting height, the minimum abdominal circumference, percentage of fat and low biliocristal breadth predispose female bases to work in pairs rather than in groups. The conclusion is that the anthropometric measurements are not decisive when guiding a gymnast toward choosing one event category or another, except for female bases
Wannier-Stark ladders in one-dimensional elastic systems
The optical analogues of Bloch oscillations and their associated
Wannier-Stark ladders have been recently analyzed. In this paper we propose an
elastic realization of these ladders, employing for this purpose the torsional
vibrations of specially designed one-dimensional elastic systems. We have
measured, for the first time, the ladder wave amplitudes, which are not
directly accessible either in the quantum mechanical or optical cases. The wave
amplitudes are spatially localized and coincide rather well with theoretically
predicted amplitudes. The rods we analyze can be used to localize different
frequencies in different parts of the elastic systems and viceversa.Comment: 10 pages, 6 figures, accepted in Phys. Rev. Let
Diferencias biomecánicas entre jugadores principiantes y de alto rendimiento en el lanzamiento en salto en baloncesto
La valoración y el aprendizaje de la técnica del lanzamiento en salto en baloncesto están relacionados
con el conocimiento de la diferencias existentes en la ejecución técnica de este gesto entre
jugadores con diferente nivel de rendimiento. Las diferencias obtenidas en las variables biomecánicas,
entre los tres niveles de rendimiento establecido, ha aportado los aspectos claves en los que debemos
focalizar nuestra atención durante la ejecución de este gesto. La muestra que se ha utilizado
para realizar esta investigación ha estado compuesta por jugadores representativos de tres niveles
de rendimiento, analizándose los lanzamientos mediante la metodología de análisis tridimensionales
de video (50 Hz). En general, se puede afirmar que las diferencias halladas entre jugadores de alto
rendimiento y jugadores en fase de aprendizaje tienen su fin en la fase final de salida del balón, en
donde los jugadores con menor nivel de rendimiento lanzan en trayectoria ascendente del centro de
gravedad con el objeto de poder aplicar al balón una gran velocidad de salida. Por lo que se deduce
que no existe un modelo teórico universal aplicable del alto rendimiento a jugadores en proceso
formativo.Peer Reviewe
Influencia de la inteligencia emocional en la autoeficacia para el liderazgo
Muchas investigaciones se han centrado en analizar y estudiar los beneficios que la inteligencia emocional podría aportar en temas de capacitación y desarrollo de personal. El objetivo de este estudio es comparar las relaciones que existen entre la inteligencia emocional rasgo de los líderes con algunos procesos emocionales; y cómo éstos procesos influyen en otras variables como la autoeficacia para el liderazgo y el desempeño. La muestra fue de 176 estudiantes de Psicología. Cada uno de ellos fue asignado aleatoriamente a los roles de líder y de seguidor, y fueron distribuidos para conformar equipos. El procedimiento de la investigación se desarrolló a lo largo de tres fases. Los resultados del estudio mostraron que la inteligencia emocional rasgo de los líderes influyó significativamente en la autoeficacia para el liderazgo y también predijo el desempeño final del equipo, aunque en este último caso su influencia es parcial. Esta investigación tiene importantes repercusiones para avanzar en la comprensión de las emociones en el lugar de trabajo.Many researches have focused on analyzing and studying the benefits of emotional intelligence could provide in training and staff development issues. The aim of this study is to compare the relationship between trait emotional intelligence of leaders with some emotional processes and how these processes affect other variables such as leadership self-efficacy, self-efficacy and collective effectiveness of a team. The sample comprised 176 students of Psychology. Each person was randomly assigned the roles of leader and follower and they were distributed to form teams. The research procedure was developed over three phases. The results showed that self-efficacy for leadership significantly influenced self-efficacy in the task of the leader and also predicted the team’s final performance; although in the latter case its influence is only partial. This research has important implications for advancing the understanding of emotions in the workplace
SU(3)c⊗SU(4)L⊗U(1)X model for three families
ABSTRACT: An extension of the Standard Model to the local gauge group SU(3)c⊗SU(4)L⊗U(1)XSU(3)c⊗SU(4)L⊗U(1)X as a three-family model is presented. The model does not contain exotic electric charges and we obtain a consistent mass spectrum by introducing an anomaly-free discrete Z2Z2 symmetry. The neutral currents coupled to all neutral vector bosons in the model are studied. By using experimental results from the CERN LEP, SLAC Linear Collider and atomic parity violation we constrain the mixing angle between two of the neutral currents in the model and the mass of the additional neutral gauge bosons to be −0.0032≤sinθ≤0.0031−0.0032≤sinθ≤0.0031 and 0.67TeV≤MZ2≤6.10.67TeV≤MZ2≤6.1 TeV at 95% C.L., respectively
El emprendedor desde el enfoque de la psicología positiva
En el presente trabajo se pretende analizar la conexión entre la psicología positiva y el comportamiento emprendedor. Desde sus orígenes y hasta hace no tanto tiempo atrás, la psicología sólo se centraba en la patología, en la debilidad y en el sufrimiento. Actualmente, el acento se pone sobre el bienestar mental o la calidad de vida para que el ser humano pueda, además de vivir saludablemente, salir fortalecido ante las adversidades o crisis que puedan presentársele. Conceptos propios de la psicología positiva como son resiliencia, motivación o felicidad, son cualidades propias del emprendedor, el cual tiene una sensibilidad especial para detectar oportunidades, movilizar recursos, interconectar información o tener ideas innovadoras. En definitiva, para hallar oportunidades donde otros no las ven o convertir en hechos lo pensado. Tener espíritu emprendedor es hacer las cosas, levantarse con más fuerza cada vez que se cae y ser capaz de convivir con la incertidumbre manteniéndose optimista. Por consiguiente, el estudio del comportamiento y el éxito emprendedor no puede ser correctamente entendido si no se aborda desde la óptica de la psicología positiva.In this paper, we expect to analyse the relationship between Positive Psychology and entrepreneur behaviour. Originally and since no some much time ago, psychology only concentrated in the pathology, weakness and suffering. Nowadays the emphasis is on the mental welfare or quality of life, so that the human being could, in addition of living healthy, get stronger in adversity or crisis that could experience.
Typical concepts of Positive Psychology as resilience, motivation and happiness, are qualities of the entrepreneur. The entrepreneur has an special feeling to detect opportunities, mobilize resources, link information or has innovative ideas. In short, to find opportunities where other people don´t see it or make thoughts real. Having entrepreneur´s nature is to do things, to get up with more strength when you have fallen and to be optimist living with uncertainty. Therefore, the study of entrepreneur´s behaviour and sucess can´t be understood if we don´t take the point of view of Positive Psychology
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