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Recurso libre

Mathematics in physics education: scanning historical evolution of the differential to find a more appropriate model for teaching differential calculus in physics
Martínez Torregrosa, Joaquín - López Gay, Rafael - Gras Martí, Albert

Formato:	info:eu-repo/semantics/article
Enlaces:	Despite its frequent use, there is little understanding of the concept of differential among upper high school and undergraduate students of physics. As a first step to identify the origin of this situation and to revert it, we have done…
Fecha:	2007-11-05
Recurso:	RUA Docencia

Recurso libre

Analytical approximations for the period of a nonlinear pendulum
Beléndez Vázquez, Augusto - Hernández Prados, Antonio - Márquez Ruiz, Andrés - Beléndez Vázquez, Tarsicio - Neipp López, Cristian

Formato:	info:eu-repo/semantics/article
Enlaces:	This paper deals with the non-linear oscillation of a simple pendulum and presents an approach for solving the non-linear differential equation that governs its movement by using the harmonic balance method. With this technique it is possible to easily obtain…
Fecha:	2007-10-27
Recurso:	RUA Docencia

Recurso libre

Application of homotopy perturbation method to the nonlinear pendulum
Beléndez Vázquez, Augusto - Hernández Prados, Antonio - Beléndez Vázquez, Tarsicio - Neipp López, Cristian - Márquez Ruiz, Andrés

Formato:	info:eu-repo/semantics/article
Enlaces:	The homotopy perturbation method is used to solve the nonlinear differential equation that governs the nonlinear oscillations of a simple pendulum, and an approximate expression for its period is obtained. Only one iteration leads to high accuracy of the solutions…
Fecha:	2007-10-27
Recurso:	RUA Docencia

Recurso libre

An improved 'heuristic' approximation for the period of a nonlinear pendulum: linear analysis of a classical nonlinear problem
Beléndez Vázquez, Augusto - Hernández Prados, Antonio - Beléndez Vázquez, Tarsicio - Márquez Ruiz, Andrés - Neipp López, Cristian

Formato:	info:eu-repo/semantics/article
Enlaces:	A new analytical approximate expression for the period of the simple pendulum is obtained by using a heuristic but pedagogical derivation. This formula depends on two parameters obtained by comparing term-by-term the power-series expansions of the approximate and exact expressions…
Fecha:	2012-05-04
Recurso:	RUA Docencia

Recurso libre

Harmonic balance approaches to the nonlinear oscillators in which the restoring force is inversely proportional to the dependent variable
Beléndez Vázquez, Augusto - Méndez Alcaraz, David Israel - Beléndez Vázquez, Tarsicio - Hernández Prados, Antonio - Álvarez López, Mariela Lázara

Formato:	info:eu-repo/semantics/article
Enlaces:	The second-order harmonic balance method is used to construct three approximate frequency-amplitude relations for a conservative nonlinear singular oscillator in which the restoring force is inversely proportional to the dependent variable. Two procedures are used to solve the nonlinear differential…
Fecha:	2009-01-26
Recurso:	RUA Docencia

Recurso libre

Asymptotic representations of the period for the nonlinear oscillator
Beléndez Vázquez, Augusto - Hernández Prados, Antonio - Beléndez Vázquez, Tarsicio - Neipp López, Cristian - Márquez Ruiz, Andrés

Formato:	info:eu-repo/semantics/article
Enlaces:	The asymptotic behaviours for small and large amplitudes, A, of the period for a nonlinear oscillator, where the square of the angular frequency depends quadratically on the velocity, are obtained. These asymptotic expressions are compared with the exact period, T(A),…
Fecha:	2007-10-27
Recurso:	RUA Docencia

Recurso libre

Comments on “investigation of the properties of the period for the nonlinear oscillator x''+(1+x^2)x'=0”
Beléndez Vázquez, Augusto - Beléndez Vázquez, Tarsicio - Hernández Prados, Antonio - Gallego Rico, Sergi - Ortuño Sánchez, Manuel - Neipp López, Cristian

Formato:	info:eu-repo/semantics/article
Enlaces:	Two Lidstedt-Poincaré perturbation based methods are used to solve the nonlinear differential equation of a nonlinear oscillator having the square of the angular frequency depends quadratically on the velocity. Mickens published two interesting papers [1, 2] about this oscillator and…
Fecha:	2007-10-27
Recurso:	RUA Docencia

Recurso libre

Application of the harmonic balance method to a nonlinear oscillator typified by a mass attached to a stretched wire
Beléndez Vázquez, Augusto - Hernández Prados, Antonio - Beléndez Vázquez, Tarsicio - Álvarez López, Mariela Lázara - Gallego Rico, Sergi - Ortuño Sánchez, Manuel - Neipp López, Cristian

Formato:	info:eu-repo/semantics/article
Enlaces:	The first-order harmonic balance method via the first Fourier coefficient is used to construct two approximate frequency–amplitude relations for a conservative nonlinear oscillatory system in which the restoring force has an irrational form. This system corresponds to the motion of…
Fecha:	2007-10-26
Recurso:	RUA Docencia

Recurso libre

Temporal response and first order volume changes during grating formation in photopolymers
Kelly, John V. - Gleeson, Michael R. - Close, Ciara E. - O'Neill, Feidhlim T. - Sheridan, John T. - Gallego Rico, Sergi - Neipp López, Cristian

Formato:	info:eu-repo/semantics/article
Enlaces:	We examine the evolution of the refractive index modulation when recording gratings in an acrylamide based photopolymer. A nonlocal diffusion model is used to predict theoretically the grating evolution. The model has been developed to account for both nonlocal spatial…
Fecha:	2009-02-13
Recurso:	RUA Docencia

Recurso libre

10.

Corrigendum to “Solution of the relativistic (an)harmonic oscillator using the harmonic balance method” [J. Sound Vib. 311 (2008) 1447–1456]
Beléndez Vázquez, Augusto - Pascual Villalobos, Carolina - Méndez Alcaraz, David Israel - Neipp López, Cristian

Formato:	info:eu-repo/semantics/article
Enlaces:	Descripción completa.
Fecha:	2009-02-02
Recurso:	RUA Docencia

Recurso libre

11.

Effect of the glass substrate on the efficiency of the different orders that propagate in a transmission sinusoidal diffraction grating
Neipp López, Cristian - Sheridan, John T. - Márquez Ruiz, Andrés - Gallego Rico, Sergi - Ortuño Sánchez, Manuel - Beléndez Vázquez, Augusto - Pascual Villalobos, Inmaculada

Formato:	info:eu-repo/semantics/article
Enlaces:	In this work we study the effect of the glass substrate on the efficiencies of the different orders that propagate inside a transmission sinusoidal diffraction grating. Holographic optical elements are usually recorded on a photosensitive medium deposited on to a…
Fecha:	2009-02-02
Recurso:	RUA Docencia

Recurso libre

12.

On the steric and mass-induced contributions to the annual sea level variations in the Mediterranean Sea
García García, David - Chao, Benjamin F. - Río, Jorge del - Vigo Aguiar, Isabel - García-Lafuente, Jesús

Formato:	info:eu-repo/semantics/article
Enlaces:	The sea level variation (SLVtotal) is the sum of two major contributions: steric and mass-induced. The steric SLVsteric is that resulting from the thermal and salinity changes in a given water column. It only involves volume change, hence has no…
Fecha:	2011-12-20
Recurso:	RUA Docencia

Recurso libre

13.

Reply to comment by L. Fenoglio-Marc et al. on “On the steric and mass-induced contributions to the annual sea level variations in the Mediterranean Sea”
García García, David - Chao, Benjamin F. - Río, Jorge del - Vigo Aguiar, Isabel - García-Lafuente, Jesús

Formato:	info:eu-repo/semantics/article
Enlaces:	Reply to comment by L. Fenoglio-Marc et al. on “On the steric and mass-induced contributions to the annual sea level variations in the Mediterranean Sea”., This work is supported by the Spanish Science and Technology Ministry Project ESP2006-11357.
Fecha:	2011-12-20
Recurso:	RUA Docencia

Recurso libre

14.

Analytical approximate solutions for conservative nonlinear oscillators by modified rational harmonic balance method
Beléndez Vázquez, Augusto - Gimeno Nieves, Encarnación - Álvarez López, Mariela Lázara - Yebra Calleja, María Soledad - Méndez Alcaraz, David Israel

Formato:	info:eu-repo/semantics/article
Enlaces:	An analytical approximate technique for conservative nonlinear oscillators is proposed. This method is a modification of the generalized harmonic balance method in which analytical approximate solutions have rational form. This approach gives us not only a truly periodic solution but…
Fecha:	2009-10-22
Recurso:	RUA Docencia

Recurso libre

15.

Solution of the relativistic (an)harmonic oscillator using the harmonic balance method
Beléndez Vázquez, Augusto - Pascual Villalobos, Carolina - Méndez Alcaraz, David Israel - Neipp López, Cristian

Formato:	info:eu-repo/semantics/article
Enlaces:	The harmonic balance method is used to construct approximate frequency–amplitude relations and periodic solutions to the relativistic oscillator. By combining linearization of the governing equation with the harmonic balance method, we construct analytical approximations to the oscillation frequencies and periodic…
Fecha:	2009-01-29
Recurso:	RUA Docencia

Recurso libre

16.

Post-buckling of a cantilever column: a more accurate linear analysis of a classical nonlinear problem
Beléndez Vázquez, Augusto - Hernández Prados, Antonio - Gallego Rico, Sergi - Ortuño Sánchez, Manuel - Neipp López, Cristian - Beléndez Vázquez, Tarsicio

Formato:	info:eu-repo/semantics/article
Enlaces:	A more accurate analytical approximate expression for the slope at any point of the elastic curve of a slender cantilever column is obtained by using a heuristic but pedagogical derivation. This derivation is based on the linearization of the nonlinear…
Fecha:	2009-03-10
Recurso:	RUA Docencia

Recurso libre

17.

Overmodulation control in the optimization of a H-PDLC device with ethyl eosin as dye
Ortuño Sánchez, Manuel - Riquelme Morell, Marina - Gallego Rico, Sergi - Márquez Ruiz, Andrés - Pascual Villalobos, Inmaculada - Beléndez Vázquez, Augusto

Formato:	info:eu-repo/semantics/article
Enlaces:	The response of a H-PDLC device is improved by means of a two-step method. First, component optimization—initiator system, crosslinker, and cosolvent—enables the diffraction efficiency of the hologram to be maximized. Second, the use of N-methyl-2-pyrrolidone in combination with N-vinyl-2-pyrrolidone prevents…
Fecha:	2013-12-04
Recurso:	RUA Docencia

Recurso libre

18.

Approximate analytical solutions for the relativistic oscillator using a linearized harmonic balance method
Beléndez Vázquez, Augusto - Méndez Alcaraz, David Israel - Álvarez López, Mariela Lázara - Pascual Villalobos, Carolina - Beléndez Vázquez, Tarsicio

Formato:	info:eu-repo/semantics/article
Enlaces:	The analytical approximate technique developed by Wu et al. for conservative oscillators with odd nonlinearity is used to construct approximate frequency-amplitude relations and periodic solutions to the relativistic oscillator. By combining Newton's method with the method of harmonic balance, analytical…
Fecha:	2009-03-11
Recurso:	RUA Docencia

Recurso libre

19.

Hot thermal X-ray emission from the Be star HD 119682
Torrejón Vázquez, José Miguel - Schulz, Norbert S. - Nowak, Michael A. - Testa, Paola - Rodes Roca, José Joaquín

Formato:	info:eu-repo/semantics/article
Enlaces:	We present an analysis of a series of four consecutive Chandra high-resolution transmission gratings observations, amounting to a total of 150 ks, of the Be X-ray source HD 119682 (=1WGA J1346.5–6255), a member of the new class of γ Cas…
Fecha:	2013-11-13
Recurso:	RUA Docencia

Recurso libre

20.

Tensorial split-field finite-difference time-domain approach for second- and third-order nonlinear materials
Francés Monllor, Jorge - Tervo, Jani - Márquez Ruiz, Andrés

Formato:	info:eu-repo/semantics/article
Enlaces:	The split-field finite-difference time-domain (SF-FDTD) method for one-dimensionally periodic structures is extended to include the coefficient-tensor description of second- and third-order nonlinear-optical media. A set of nonlinear equations related to the split-field values of the electric field is established. An…
Fecha:	2013-09-06
Recurso:	RUA Docencia

Recurso libre

21.

Linearization of conservative nonlinear oscillators
Beléndez Vázquez, Augusto - Álvarez López, Mariela Lázara - Fernández Varó, Elena - Pascual Villalobos, Inmaculada

Formato:	info:eu-repo/semantics/article
Enlaces:	A linearization method of the nonlinear differential equation for conservative nonlinear oscillators is analyzed and discussed. This scheme is based on the Chebyshev series expansion of the restoring force which allows us to obtain a frequency-amplitude relation which is valid…
Fecha:	2009-01-26
Recurso:	RUA Docencia

Recurso libre

22.

Approximation for a large-angle simple pendulum period
Beléndez Vázquez, Augusto - Rodes Roca, José Joaquín - Beléndez Vázquez, Tarsicio - Hernández Prados, Antonio

Formato:	info:eu-repo/semantics/article
Enlaces:	An approximation scheme to obtain the period for large amplitude oscillations of a simple pendulum is analysed and discussed. The analytical approximate formula for the period is the same as that suggested by Hite (2005 Phys. Teach. 43 290), but…
Fecha:	2009-02-25
Recurso:	RUA Docencia

Recurso libre

23.

The contribution of fast neutrals to cathode erosion in glow discharges
Abril Sánchez, Isabel - Gras Martí, Albert - Vallés Abarca, José Antonio

Formato:	info:eu-repo/semantics/article
Enlaces:	We calculate the rate at which a target located at the cathode of a glow discharge is sputtered. The calculation involves two steps: (1) evaluation of the energy distribution functions of ions and neutrals impinging on the target; and (2)…
Fecha:	2013-01-07
Recurso:	RUA Docencia

Recurso libre

24.

Development of a unified FDTD-FEM library for electromagnetic analysis with CPU and GPU computing
Francés Monllor, Jorge - Bleda Pérez, Sergio - Gallego Rico, Sergi - Neipp López, Cristian - Márquez Ruiz, Andrés - Pascual Villalobos, Inmaculada - Beléndez Vázquez, Augusto

Formato:	info:eu-repo/semantics/article
Enlaces:	The present paper describes an optimized C++ library for the study of electromagnetics. The implementation is based on the Finite-Difference Time-Domain method for transient analysis, and the Finite Element Method for electrostatics. Both methods share the same core and are…
Fecha:	2013-05-07
Recurso:	RUA Docencia

Recurso libre

25.

A novel rational harmonic balance approach for periodic solutions of conservative nonlinear oscillators
Beléndez Vázquez, Augusto - Gimeno Nieves, Encarnación - Álvarez López, Mariela Lázara - Gallego Rico, Sergi - Ortuño Sánchez, Manuel - Méndez Alcaraz, David Israel

Formato:	info:eu-repo/semantics/article
Enlaces:	An analytical approximate procedure for a class of conservative single degree-of-freedom nonlinear oscillators with odd non-linearity is proposed. This technique is based on the generalized harmonic balance method in which analytical approximate solutions have rational forms. Unlike the classical harmonic…
Fecha:	2012-05-04
Recurso:	RUA Docencia

Recurso libre

26.

Linearized harmonic balancing approach for accurate solutions to the dynamically shifted oscillator
Beléndez Vázquez, Augusto - Rodes Roca, José Joaquín - Fuentes Rosillo, Rosa - García Llopis, Celia - Yebra Calleja, María Soledad - Pascual Villalobos, Inmaculada

Formato:	info:eu-repo/semantics/article
Enlaces:	The analytical approximate technique developed by Wu et al for conservative oscillators with odd nonlinearity is used to construct approximate frequency-amplitude relations and periodic solutions to the dynamically shifted oscillator. This nonlinear oscillator is described by an equation of motion…
Fecha:	2012-05-04
Recurso:	RUA Docencia

Recurso libre

27.

Higher accuracy approximate solution for oscillations of a mass attached to a stretched elastic wire by rational harmonic balance method
Gimeno Nieves, Encarnación - Álvarez López, Mariela Lázara - Yebra Calleja, María Soledad - Rosa Herranz, Julio Luis - Beléndez Vázquez, Augusto

Formato:	info:eu-repo/semantics/article
Enlaces:	A second-order modified rational harmonic balance method is used for approximately solve the nonlinear differential equation that governs the oscillations of a system typified as a mass attached to a stretched elastic wire for which the restoring force for this…
Fecha:	2012-05-04
Recurso:	RUA Docencia

Recurso libre

28.

The young open cluster Berkeley 55
Negueruela Díez, Ignacio - Marco Tobarra, Amparo

Formato:	info:eu-repo/semantics/article
Enlaces:	We present UBV photometry of the highly reddened and poorly studied open cluster Berkeley 55, revealing an important population of B-type stars and several evolved stars of high luminosity. Intermediate-resolution far-red spectra of several candidate members confirm the presence of…
Fecha:	2013-11-13
Recurso:	RUA Docencia

Recurso libre

29.

Target inner-shells contributions to the stopping power and straggling for H and He ions in gold
Heredia Ávalos, Santiago - Abril Sánchez, Isabel - Denton Zanello, Cristian D. - Moreno Marín, Juan Carlos - García Molina, Rafael

Formato:	info:eu-repo/semantics/article
Enlaces:	The electronic energy loss of swift H and He ions in gold is studied, paying special attention to the contribution to the projectile energy loss due to the ionization of the target inner-shells. We calculate the stopping power and the…
Fecha:	2012-11-27
Recurso:	RUA Docencia

Recurso libre

30.

The Canada-France Ecliptic Plane Survey—full data release: the orbital structure of the Kuiper Belt
Petit, Jean-Marc - Kavelaars, J. John - Gladman, Brett J. - Jones, R. Lynne - Parker, Joel Wm. - Van Laerhoven, Christa - Nicholson, Phil - Mars, Gilbert - Rousselot, Philippe - Mousis, Olivier - Marsden, Brian - Bieryla, Allyson - Taylor, Matthew - Ashby, Matthew L.N. - Benavídez, Paula Gabriela - Campo Bagatín, Adriano - Bernabeu Pastor, José Guillermo

Formato:	info:eu-repo/semantics/article
Enlaces:	We report the orbital distribution of the trans-Neptunian objects (TNOs) discovered during the Canada-France Ecliptic Plane Survey (CFEPS), whose discovery phase ran from early 2003 until early 2007. The follow-up observations started just after the first discoveries and extended until…
Fecha:	2013-11-13
Recurso:	RUA Docencia

Recurso libre

31.

Chandra and Suzaku observations of the Be/X-ray star HD110432
Torrejón Vázquez, José Miguel - Schulz, Norbert S. - Nowak, Michael A.

Formato:	info:eu-repo/semantics/article
Enlaces:	We present an analysis of a pointed 141 ks Chandra high-resolution transmission gratings observation of the Be X-ray emitting star HD110432, a prominent member of the γ Cas analogs. This observation represents the first high-resolution spectrum taken for this source…
Fecha:	2013-11-13
Recurso:	RUA Docencia