Summary of Dissertation Recitals One Opera Role and Two Vocal Music Recitals

One operatic role and two vocal music recitals were performed in lieu of a written dissertation. Friday, November 9, 2012, 8:00pm; Saturday, November 10, 2012, 8:00pm; Sunday, November 11, 2012, 2:00pm, Power Center, University of Michigan Opera Theater. Don Giovanni by Wolfgang Amadeus Mozart; Robert Swedberg, director, Christopher Lees, conductor. Performed the role of Don Giovanni. Monday, April 1, 2013, 5:00pm, Stamps Auditorium, Walgreen Drama Center. Assisted by Lydia Qiu, piano. Program: “Loveliest of trees”, “When I was one and twenty”, “The Lads in their hundreds”, “Is my team ploughing”, “Bredon Hill”, and “On the idle hill of summer”, from A Shropshire Lad and Bredon Hill and Other Songs by George Butterworth; “A last song”, “My Lizard”, “In the Wilderness”, “Solitary Hotel”, and “Despite and Still” from Despite and Still and Dover Beach by Samuel Barber; “And so, goodbye”, “When I have sung my songs”, “If you only knew”, and “O lovely world” by Ernest Charles. Saturday, May 4, 2013, 8:00pm, Stamps Auditorium, Walgreen Drama Center, Assisted by Lydia Qiu, piano, Xavier Suarez, piano, and Imani Mchunu, soprano. Program: “El paño Moruno”, “Seguidilla murciana”, “Asturiana”, “Jota”, “Nana”, “Canción”, and “Polo”, from Siete Canciones Populares Españolas by Manuel de Falla; “La mi sola, Laureola”, “Al Amor”, “Con amores, la mi madre”, “Corazón, porque pasáis…”, “Del cabello más sutil”, and “El vito”, from Canciones Clasicas Españolas by Fernando Obradors; “Chacarera”, “Triste”, “Zamba”, “Arrorró”, and “Gato”, from Cinco Canciones Populares Argentinas by Alberto Ginastera; “Mi Aldea” from Los Gavilanes by Jacinto Guerrero; “Amor, vida de mi vida”, from Maravilla by Federico Moreno Torroba; “Duo de Felipe y Mari-pepa”, from La Revoltosa by Ruperto Chapí.AMUMusic: PerformanceUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/147650/1/juanhp_1.pd

A new neural network technique for the design of multilayered microwave shielded bandpass filters

In this work, we propose a novel technique based on neural networks, for the design of microwave filters in shielded printed technology. The technique uses radial basis function neural networks to represent the non linear relations between the quality factors and coupling coefficients, with the geometrical dimensions of the resonators. The radial basis function neural networks are employed for the first time in the design task of shielded printed filters, and permit a fast and precise operation with only a limited set of training data. Thanks to a new cascade configuration, a set of two neural networks provide the dimensions of the complete filter in a fast and accurate way. To improve the calculation of the geometrical dimensions, the neural networks can take as inputs both electrical parameters and physical dimensions computed by other neural networks. The neural network technique is combined with gradient based optimization methods to further improve the response of the filters. Results are presented to demonstrate the usefulness of the proposed technique for the design of practical microwave printed coupled line and hairpin filters

Characterization of bathtub distributions via percentile residual life functions

In reliability theory and survival analysis, many set of data are generated by distributions with bathtub shaped hazard rate functions. Launer (1993) established several relations between the behaviour of the hazard rate function and the percentile residual life function. In particular, necessary conditions were given for a special type of bathtub distributions in terms of percentile residual life functions. The purpose of this paper is to complete the study initiated by Launer (1993) and to characterize (necessary and sufficient conditions) all types of bathtub distributions.Percentile residual life, Bathtub hazard rate, Aging notions,

The percentile residual life up to time t0: ordering and aging properties

Motivated by practical issues, a new stochastic order for random variables is introduced by comparing all their percentile residual life functions until a certain instant. Some interpretations of these stochastic orders are given, and various properties of them are derived. The relationships to other stochastic orders are studied, and also an application in Reliability Theory is described. Finally, we present some characterization results of the decreasing percentile residual life up to time t0 aging notion.Aging notion, Hazard rate, Mean residual life, Percentile residual life, Reliability, Stochastic ordering

Social representations on remote teaching during covid-19 pandemic in teenage students in a non-bilingual public school in Barranquilla, Colombia

This article presents the results of a research aimed at understanding the social representations of secondary school students about English classes during the Covid-19 pandemic in an educational institution in Barranquilla. The process of digital adoption of methodologies and tools in the pandemic lead to new conditions and dynamics for the development of classes which in turn, trigger changes in school achievement, performance and learning experiences. The present research involved 8th grade students who had experienced the temporary change from face-to-face to remote English classes. The method used was the structural approach of social representations, along free association techniques to describe its contents, and hierarchization techniques complemented to Likert-type scales to create a hypothesis about the central core. The results show that the most salient element is attitudes, significantly polarized between approval and disapproval of remote English classes, with "Learning", "Fun", "Easy", as well as "Difficult", "Complicated" or "Stressful" being central terms. The findings point to the need to explore further the heterogeneity of students' conditions of access to technology, and their personal experiences, which would merit future studies based on such experiences.MaestríaMagister en la Enseñanza del Ingle

Comparing quantile residual life functions by confidence bands

A quantile residual life function is the quantile of the remaining life of a surviving subject, as it varies with time. In this article we present a nonparametric method for constructing confidence bands for the difference of two quantile residual life functions. These bands provide evidence for two random variables ordering with respect to a quantile residual life order introduced in Franco-Pereira et al. (2010). A simulation study has been carried out in order to evaluate and illustrate the performance and the consistency of this new methodology. We also present applications to real data examples.Quantile residual life, Confidence bands

Numerical evaluation of the Green's functions for arbitrarily shaped cylindrical enclosures and their optimization by a new spatial images method

IIn this paper, a spatial image technique is used to efficiently calculate the mixed potential Green’s functions associated with electric sources, when they are placed inside arbitrarily shaped cylindrical cavities. The technique is based on placing electric dipole images and charges outside the cavity region. Their strength and orientation are thencalculated by imposing the appropriate boundary conditions for the fields at discrete points on the metallic wall. A method for the assessment of the potentials accuracy is proposed, and several optimization techniques are presented. Three cavities are analyzed to demonstrate the usefulness of the techniques. The cutoff frequencies and potentials patterns are compared to those obtained by a standard finite elements technique, showing excellent agreement. Finally, a band-pass filter based on coupled lines is analyzed, demonstrating the practical value of the technique.This work has been developed with support from the Spanish National Project (CICYT) with reference TEC2004-04313-C02-02/TCM, and the Regional Seneca Project with reference 02972/PI/0

Detecting and Monitoring Hate Speech in Twitter

Social Media are sensors in the real world that can be used to measure the pulse of societies. However, the massive and unfiltered feed of messages posted in social media is a phenomenon that nowadays raises social alarms, especially when these messages contain hate speech targeted to a specific individual or group. In this context, governments and non-governmental organizations (NGOs) are concerned about the possible negative impact that these messages can have on individuals or on the society. In this paper, we present HaterNet, an intelligent system currently being used by the Spanish National Office Against Hate Crimes of the Spanish State Secretariat for Security that identifies and monitors the evolution of hate speech in Twitter. The contributions of this research are many-fold: (1) It introduces the first intelligent system that monitors and visualizes, using social network analysis techniques, hate speech in Social Media. (2) It introduces a novel public dataset on hate speech in Spanish consisting of 6000 expert-labeled tweets. (3) It compares several classification approaches based on different document representation strategies and text classification models. (4) The best approach consists of a combination of a LTSM+MLP neural network that takes as input the tweet’s word, emoji, and expression tokens’ embeddings enriched by the tf-idf, and obtains an area under the curve (AUC) of 0.828 on our dataset, outperforming previous methods presented in the literatureThe work by Quijano-Sanchez was supported by the Spanish Ministry of Science and Innovation grant FJCI-2016-28855. The research of Liberatore was supported by the Government of Spain, grant MTM2015-65803-R, and by the European Union’s Horizon 2020 Research and Innovation Programme, under the Marie Sklodowska-Curie grant agreement No. 691161 (GEOSAFE). All the financial support is gratefully acknowledge