Microscopic study of neutron-rich Dysprosium isotopes

Microscopic studies in heavy nuclei are very scarce due to large valence spaces involved. This computational problem can be avoided by means of the use of symmetry based models. Ground-state, gamma and beta-bands, and their B(E2) transition strengths in 160-168Dy isotopes, are studied in the framework of the pseudo-SU(3) model which includes the preserving symmetry Q.Q term and the symmetry-breaking Nilsson and pairing terms, systematically parametrized. Additionally, three rotor-like terms are considered whose free parameters, fixed for all members of the chain are used to fine tune the moment of inertia of rotational bands and the band-head of gamma and beta-bands. The model succesfully describes in a systematic way rotational features in these nuclei and allows to extrapolate toward the midshell nucleus 170Dy. The results presented show that it is possible to study full chain of isotopes or isotones in the region with the present model

On involution kernels and large deviations principles on β\beta-shifts

Consider $\beta > 1$ and $\lfloor \beta \rfloor$ its integer part. It is widely known that any real number $\alpha \in \Bigl[0, \frac{\lfloor \beta \rfloor}{\beta - 1}\Bigr]$ can be represented in base $\beta$ using a development in series of the form $\alpha = \sum_{n = 1}^\infty x_n\beta^{-n}$, where $x = (x_n)_{n \geq 1}$ is a sequence taking values into the alphabet $\{0,\; ...\; ,\; \lfloor \beta \rfloor\}$. The so called $\beta$-shift, denoted by $\Sigma_\beta$, is given as the set of sequences such that all their iterates by the shift map are less than or equal to the quasi-greedy $\beta$-expansion of $1$. Fixing a H\"older continuous potential $A$, we show an explicit expression for the main eigenfunction of the Ruelle operator $\psi_A$, in order to obtain a natural extension to the bilateral $\beta$-shift of its corresponding Gibbs state $\mu_A$. Our main goal here is to prove a first level large deviations principle for the family $(\mu_{tA})_{t>1}$ with a rate function $I$ attaining its maximum value on the union of the supports of all the maximizing measures of $A$. The above is proved through a technique using the representation of $\Sigma_\beta$ and its bilateral extension $\widehat{\Sigma_\beta}$ in terms of the quasi-greedy $\beta$-expansion of $1$ and the so called involution kernel associated to the potential $A$

New tools for analyzing the Mexican economy: indexes of coincident and leading economic indicators

New composite indexes presented in this article could prove useful in analyzing and forecasting the Mexican economy. Keith Phillips, Lucinda Vargas, and Victor Zarnowitz present composite indexes of leading and coincident indexes for Mexico. In constructing the indexes, the economists use an approach similar to that developed by the National Bureau of Economic Research to create the composite indexes of U.S. economic activity. The authors classify peaks and troughs in the Mexican business cycle since 1980. Using these business cycle turning points, the authors determine which indicators consistently turned down prior to recessions and turned up prior to expansions. Eight of the best performing indicators are combined to create a composite index of leading economic indicators.Texas ; Economic indicators

Fraud detection in energy consumption: a supervised approach

Data from utility meters (gas, electricity, water) is a rich source of information for distribution companies, beyond billing. In this paper we present a supervised technique, which primarily but not only feeds on meter information, to detect meter anomalies and customer fraudulent behavior (meter tampering). Our system detects anomalous meter readings on the basis of models built using machine learning techniques on past data. Unlike most previous work, it can incrementally incorporate the result of field checks to grow the database of fraud and non-fraud patterns, therefore increasing model precision over time and potentially adapting to emerging fraud patterns. The full system has been developed with a company providing electricity and gas and already used to carry out several field checks, with large improvements in fraud detection over the previous checks which used simpler techniques.Peer ReviewedPostprint (author's final draft

Entropy, pressure, ground states and calibrated sub-actions for linear dynamics

Denote by $X$ a Banach space and by $T : X \to X$ a bounded linear operator with non-trivial kernel satisfying suitable conditions. We consider the concepts of entropy - for $T$-invariant probability measures - and pressure for H\"older continuous potentials. We also prove the existence of ground states (the limit when temperature goes to zero) associated with such class of potentials when the Banach space $X$ is equipped with a Schauder basis. We produce an example concerning weighted shift operators defined on the Banach spaces $c_0(\mathbb{R})$ and $l^p(\mathbb{R})$, $1 \leq p < +\infty$, where our results do apply. In addition, we prove the existence of calibrated sub-actions when the potential satisfies certain regularity conditions using properties of the so-called Ma\~n\'e potential. We also exhibit examples of selection at zero temperature and explicit sub-actions in the class of H\"older continuous potentials

The Ruelle operator for symmetric β\beta-shifts

Consider $m \in \mathbb{N}$ and $\beta \in (1, m + 1]$. Assume that $a\in \mathbb{R}$ can be represented in base $\beta$ using a development in series $a = \sum^{\infty}_{n = 1}x(n)\beta^{-n}$ where the sequence $x = (x(n))_{n \in \mathbb{N}}$ take values in the alphabet $\mathcal{A}_m := \{0, \ldots, m\}$. The above expression is called the $\beta$-expansion of $a$ and it is not necessarily unique. We are interested in sequences $x = (x(n))_{n \in \mathbb{N}} \in \mathcal{A}_m^\mathbb{N}$ which are associated to all possible values $a$ which have a unique expansion. We denote the set of such $x$ (with some more technical restrictions) by $X_{m,\beta} \subset\mathcal{A}_m^\mathbb{N}$. The space $X_{m, \beta}$ is called the symmetric $\beta$-shift associated to the pair $(m, \beta)$. It is invariant by the shift map but in general it is not a subshift of finite type. Given a H\"older continuous potential $A:X_{m, \beta} \to\mathbb{R}$, we consider the Ruelle operator $\mathcal{L}_A$ and we show the existence of a positive eigenfunction $\psi_A$ and an eigenmeasure $\rho_A$ for some appropriated values of $m$ and $\beta$. We also consider a variational principle of pressure. Moreover, we prove that the family of entropies $h(\mu_{tA})_{t>1}$ converges, when $t \to\infty$, to the maximal value among the set of all possible values of entropy of all $A$-maximizing probabilities

Applying bottom-up listening strategies to eighth grade in a public high school

El presente estudio busca observar la percepción de los estudiantes y el impacto al aplicar la estrategia de escucha "bottom-up" en la clase de ingles, la cual consiste que los estudiantes escuchen partes individuales del lenguaje como palabras, terminación de formas gramaticales, entonación etc. Para lograr los objetivos del estudio, los investigadores llevaron a cabo los siguientes pasos: primero se desarrollaron observaciones a las clases de Ingles de un colegio en Pereira RDA, en las cuales se observó que el profesor no usaba suficientes estrategias para desarrollar la habilidad de escucha en los estudiantes, los cuales solo escuchaban el ingles cuando la profesora leía lo que estaba escrito en el tablero. Después de estas observaciones se elaboraron dos preguntas que encabezarían el estudio: ¿Cuáles son las percepciones de los estudiantes durante la aplicación de la estrategia para la escucha "bottom-up"? ¿Cuál es el impacto en términos de aprendizaje del lenguaje durante la aplicación de la estrategia para la escucha "bottom-up"? Bottom-up listening strategies. 4 Para dar respuesta a estas preguntas se llevo a cabo una investigación de tipo cualitativo, y los instrumentos que se usaron para recolectar datos fueron, diarios de campo, videos y cuestionarios. Los datos que se recolectaron gracias a los instrumentos fueron codificados para obtener categorías y dar respuesta a las preguntas formuladas, y finalmente estas categorías fueron discutidas con base en teorías desarrolladas por expertos que habían hecho investigaciones anteriores en este campo del conocimiento.The current study is based on listening comprehension techniques applying bottomup listening strategies. In this study our first observations were addressed to eighth graders of a high school in Pereira where we found that the amount of listening practice was not sufficient to develop the learners’ listening skill. After observing this fact, we decided to implement bottom-up listening strategies to provide the learners with opportunities to receive listening input. Consequently, we formulated two questions that aimed to find answers to what learners’ perceptions were, and what the impact on learners’ listening skill was when applying bottom-up listening strategies. To answer these questions we applied qualitative research. The instruments that we used to collect data were field notes, video recordings, and questionnaires. The collected data was analyzed in order to obtain findings that gave answers to our research questions. Those findings were discussed based on what experts have written about the field to support and enlighten the results of our stud