Plan de clase de la unidad de óptica reflexión y refracción

Debido a los altos índices de estudiantes que reprueban la materia Física D, se ha decidido realizar un plan piloto para implementar un plan de estudio que incluya el cambio de metodología para el dictado de esta materia. La metodología a seguir está basada en el método de Gagne, ya que este pone énfasis en el aprendizaje para lograr el desarrollo individual y promueve el desarrollo de habilidades más complejas en el individuo. El método de Gagne se fundamenta en la teoría del procesamiento de la información, que se refiere a la secuencia de procesos y operaciones mentales que se realizan para llegar a un conocimiento organizado de grandes cantidades de información. Las variables que interfieren en la aplicación de este método son: 1. Los procesos de aprendizaje 2. Las fases del aprendizaje 3. Los resultados del aprendizaje 4. Las condiciones del aprendizaj

Generalized Parton Distributions of ^3He

A realistic microscopic calculation of the unpolarized quark Generalized Parton Distribution (GPD) $H_q^3$ of the $^3He$ nucleus is presented. In Impulse Approximation, $H_q^3$ is obtained as a convolution between the GPD of the internal nucleon and the non-diagonal spectral function, describing properly Fermi motion and binding effects. The proposed scheme is valid at low values of $\Delta^2$, the momentum transfer to the target, the most relevant kinematical region for the coherent channel of hard exclusive processes. The obtained formula has the correct forward limit, corresponding to the standard deep inelastic nuclear parton distributions, and first moment, giving the charge form factor of $^3He$. Nuclear effects, evaluated by a modern realistic potential, are found to be larger than in the forward case. In particular, they increase with increasing the momentum transfer when the asymmetry of the process is kept fixed, and they increase with the asymmetry at fixed momentum transfer. Another relevant feature of the obtained results is that the nuclear GPD cannot be factorized into a $\Delta^2$-dependent and a $\Delta^2$-independent term, as suggested in prescriptions proposed for finite nuclei. The size of nuclear effects reaches 8 % even in the most important part of the kinematical range under scrutiny. The relevance of the obtained results to study the feasibility of experiments is addressed.Comment: 23 pages, 8 figures; Discussion in section II enlarged; discussion in section IV shortened. Final version accepted by Phys. Rev.

A (p/E) Calculation of Strong Pionic Decays of Baryons

Strong pionic decays of baryons are studied in a non-relativistic quark model framework via a convergent (p/E) expansion of the transition operator. Results are compared to the ones obtained within a more conventional (p/m) expansion.Comment: 16 pages, LaTeX, using amssymb.st

Empathic and Nonempathic Interaction in Chronic Pain Couples

Empathy and empathic response are receiving greater attention in pain research as investigators acknowledge that other forms of interaction may impact the pain process. The purpose of this study was to examine validation and invalidation as forms of empathic and nonempathic responses in chronic pain couples. Participants were 92 couples in which at least one spouse reported chronic musculoskeletal pain. Each couple participated in two videotaped interactions about the ways in which the pain has impacted their lives together. Trained raters then coded interactions for each partner’s use of validation and invalidation. Couples also completed surveys on spouse responses to pain, marital satisfaction, and perceived spousal support. Correlations demonstrated validation by spouses of persons with pain was associated with punishing, solicitous, and distracting spouse responses to pain, marital satisfaction, and perceived spousal support. In contrast, spouses’ invalidation scores were correlated with punishing spouse responses. Exploratory factor analyses were then conducted to determine the extent to which spouses’ responses to pain and spouse validation and invalidation loaded on similar factors. Results indicated that validation and invalidation are more closely related to punishing spouse responses than to solicitous or distracting spouse responses. These results have implications for theoretical and clinical work on spouse responding

Band Connectivity for Topological Quantum Chemistry: Band Structures As A Graph Theory Problem

The conventional theory of solids is well suited to describing band structures locally near isolated points in momentum space, but struggles to capture the full, global picture necessary for understanding topological phenomena. In part of a recent paper [B. Bradlyn et al., Nature 547, 298 (2017)], we have introduced the way to overcome this difficulty by formulating the problem of sewing together many disconnected local "k-dot-p" band structures across the Brillouin zone in terms of graph theory. In the current manuscript we give the details of our full theoretical construction. We show that crystal symmetries strongly constrain the allowed connectivities of energy bands, and we employ graph-theoretic techniques such as graph connectivity to enumerate all the solutions to these constraints. The tools of graph theory allow us to identify disconnected groups of bands in these solutions, and so identify topologically distinct insulating phases.Comment: 19 pages. Companion paper to arXiv:1703.02050 and arXiv:1706.08529 v2: Accepted version, minor typos corrected and references added. Now 19+epsilon page

Time series segmentation based on stationarity analysis to improve new samples prediction

A wide range of applications based on sequential data, named time series, have become increasingly popular in recent years, mainly those based on the Internet of Things (IoT). Several different machine learning algorithms exploit the patterns extracted from sequential data to support multiple tasks. However, this data can suffer from unreliable readings that can lead to low accuracy models due to the low-quality training sets available. Detecting the change point between high representative segments is an important ally to find and thread biased subsequences. By constructing a framework based on the Augmented Dickey-Fuller (ADF) test for data stationarity, two proposals to automatically segment subsequences in a time series were developed. The former proposal, called Change Detector segmentation, relies on change detection methods of data stream mining. The latter, called ADF-based segmentation, is constructed on a new change detector derived from the ADF test only. Experiments over real-file IoT databases and benchmarks showed the improvement provided by our proposals for prediction tasks with traditional Autoregressive integrated moving average (ARIMA) and Deep Learning (Long short-term memory and Temporal Convolutional Networks) methods. Results obtained by the Long short-term memory predictive model reduced the relative prediction error from 1 to 0.67, compared to time series without segmentation

Low-temperature specific heat of real crystals: Possibility of leading contribution of optical and short-wavelength acoustical vibrations

We point out that the repeatedly reported glass-like properties of crystalline materials are not necessarily associated with localized (or quasilocalized) excitations. In real crystals, optical and short-wavelength acoustical vibrations remain damped due to defects down to zero temperature. If such a damping is frequency-independent, e.g. due to planar defects or charged defects, these optical and short-wavelength acoustical vibrations yield a linear-in-$T$ contribution to the low-temperature specific heat of the crystal lattices. At low enough temperatures such a contribution will prevail over that of the long-wavelength acoustical vibrations (Debye contribution). The crossover between the linear and the Debye regime takes place at $T^* \propto \sqrt N$, where $N$ is the concentration of the defects responsible for the damping. Estimates show that this crossover could be observable.Comment: 5 pages. v4: Error in Appendix corrected, which does not change the main results of the pape

Stiff oscillatory systems, delta jumps and white noise

Two model problems for stiff oscillatory systems are introduced. Both comprise a linear superposition of N >> 1 harmonic oscillators used as a forcing term for a scalar ODE. In the first case the initial conditions are chosen so that the forcing term approximates a delta function as N tends to infinity, and in the second case so that it approximates white noise. In both cases the fastest natural frequency of the oscillators is O(N). The model problems are integrated numerically in the stiff regime where the time step is of size O(1/N). The convergence of the algorithms is studied in this case in the limit of N tending to infinity and the time step tending to zero. For the white noise problem both strong and weak convergence are considered