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This article presents an evaluation of Prony method estimation and its implementation considerations for surge comparison test application in turn insulation diagnostics for three-phase stator windings. Surge testing diagnostics compares recorded surge voltage signals of motor winding, and a diagnostic is then defined with a defined value of EAR (error area ratio), which evaluates the difference between signals to determine a turn insulation diagnostic. First, an overview of surge testing is presented. Next, the Prony method and the considerations for its implementation in surge testing are described. Then, a numerical simulation is used to define a simulated turn fault surge voltage signal, where its parameters can be obtained with Prony method estimation and compared with EAR to evaluate its performance. Lastly, recorded surge test signals from two tested motors are used to validate Prony method estimation application for surge test diagnostics, where twelve recorded surge signals for no-fault and fault conditions were analyzed. The summary results of the surge signals parameter estimation are presented in the results and discussion section.

Socio-emotional skills have been recognized for generating great benefits in the academic progress of students, however, these do not have been appreciated based on its fair value. In the present investigation were used data from the National Plan for the Evaluation of Learning for the year 2017, this to determine the weight they have these skills (perseverance, empathy, self-regulation and positive and negative decisions) with the results in the areas of language and communication and mathematics in a sample of 4,822 students of high school in Nuevo León, Mexico. A theoretical model was proposed to represent the relationship and determine the weight that the proposed factors have in the achievement in the referred areas; for the empirical verification, applied the technique of modeling with structural equations. It was found that all the factors have a significant weight in the result in the described areas. The practical implication that is derived is that it is pertinent that in the educational field students are also trained in these skills.

La violencia escolar es una acción que se ha venido manifestando a través de los años y esta ha afectado la vida de quienes la han padecido. Específicamente, el bachillerato es vulnerable a la violencia y va generando consecuencias negativas en los estudiantes, tanto en el ámbito escolar como en el personal. Es por ello que el objetivo del presente trabajo es determinar los factores que se relacionan con dicha violencia en estudiantes de este nivel, con la finalidad de contribuir a su prevención. El tipo de estudio fue no experimental, transversal, descriptivo y correlacional. La muestra estuvo conformada por 4.822 estudiantes. Se utilizaron los resultados de las Evaluaciones de Logro referidas al Sistema Educativo Nacional (ELSEN) y del cuestionario de contexto, ambos correspondientes al Plan Nacional para la Evaluación de los Aprendizajes (PLANEA) 2017. Se hizo una revisión exhaustiva de la literatura y de ahí se derivaron los factores propuestos en un modelo teórico. Se determinó la cantidad de alumnos que sufría de violencia escolar con base en su sexo y el tipo de escuela. Fueron aplicadas las pruebas t de student y la U de Mann-Whitney para evidenciar uno de los aspectos adversos que padecían los alumnos que experimentaban violencia escolar. Fue aplicada la técnica de modelaje con ecuaciones estructurales para verificar empíricamente el modelo teórico. Entre los hallazgos, se encontró una relación directa de la Violencia con los factores Emociones, Metas, Laboral y Relaciones, e indirecta con Actitud, Padres y Bienes. En conclusión, y tomando como base los resultados arrojados y las revisiones de diferentes autores, la violencia escolar está presente, no obstante, puede ser prevenida si se toman en cuenta los factores propuestos.

This article presents an evaluation of Prony method and its implementation considerations for motor current signal analysis diagnostics in rotor cage induction motors. The broken rotor bar fault signature in current signals is evaluated using Prony method, where its advantages in comparison with fast Fourier transform are presented. The broken rotor bar fault signature could occur during the life cycle operation of induction motors, so that is why an effective early detection estimation technique of this fault could prevent an insulation failure or heavy damage, leaving the motor out of service. First, an overview of cage winding defects in rotor cage induction motors is presented. Next, Prony method and its considerations for the implementation in current signature analysis are described. Then, the performance of Prony method using numerical simulations is evaluated. Lastly, an assessment of Prony method as a tool for current signal analysis diagnostics is performed using a laboratory test system where real signals of an induction motor with broken rotor bar operated with/without a variable frequency drive are analyzed. The summary results of the estimation (amplitudes and frequencies) are presented in the results and discussion section.

Reading is one of the aspects that help students achieve optimal performance in their education. There are several determining factors that can affect reading, particularly its promotion by teachers, and the students’ behavior and comprehension. This paper seeks to determine the relationship between reading promotion, behavior, and comprehension and educational achievement in Mexican high school students. Our sample consisted of 7,299 students, with an average age of 15.8 years. We analyzed their answers to a questionnaire as well as the database from the 2018 Program for International Student Assessment (PISA) test. A theoretical model was built using the reading promotion, reading behavior, reading comprehension, and educational achievement factors; the model was evaluated using the structural equation modelling technique. We found a positive and significant relationship between reading promotion, behavior, and comprehension and educational achievement. We conclude that, in order to improve educational achievement, teachers should perform specific actions to promote favorable reading behavior and comprehension among high school students in Mexico.

This article presents a comparative analysis for the design considerations for a solar power generation transformer. One of the main existing problems in transformer manufacturing is in the renewable energy field, specifically the solar power generation, where the transformer connected to the inverter is operated under a certain harmonic content and operating conditions. The operating conditions of the transformer connected to the inverter are particularly unknown for each solar power plant; thus, the transformer will be subject to a particular harmonic content, which is defined by the inverter of the solar power plant. First, the fundamental calculations for solar power plant transformer and the proposed methodology for the design calculation of the distribution pad-mounted three phase transformer are presented. Then, a design study case is described where a distribution transformer and an inverter of a particular solar power plant are used for the analysis. Next, the transformer under analysis is modeled using finite element analysis in ANSYS Maxwell® software, where the transformer will be designed for a non-harmonic and harmonic content application. Lastly, the main design parameters, flux density, the core losses and the winding excitation voltage of the transformer are calculated and presented in results and discussion section.

The aim was to evaluate if medetomidine and dexmedetomidine affected arterial ovarian blood flow in dogs. The dogs were randomly assigned to two different groups. In Group 1, medetomidine (10 µg/kg) was administered intramuscularly and, in Group 2, dexmedetomidine (5 µg/kg) was used. After a preliminary exam, arterial blood pressure (BP) was measured and a duplex Doppler ultrasonographic examination of both ovarian arteries was performed. Twenty minutes after the administration of medetomidine or dexmedetomidine, BP and ovarian Doppler ultrasonography were repeated. High quality tracings of ovarian artery flow velocity were obtained in all dogs and Doppler parameters: Peak Systolic Velocity (PSV), End Diastolic Velocity (EDV) and Resistive Index (RI) were measured before and after drug administration in the left (LO) and right (RO) ovaries. PSV and EDV values decreased significantly after drug administration (p < 0.05) compared to the non-sedated values, but no differences were found between the LO and RO (p > 0.05). The RI was not affected by drugs administration in neither of the groups studied (p > 0.05). In conclusion, the administration of medetomidine or dexmedetomidine causes a decrease in blood flow velocity in the ovarian artery and may be a good choice to avoid excessive bleeding prior surgeries in which ovariectomy.

El objetivo de esta contribución es determinar la asociación entre los factores personales, contextuales y tecnológicos con el logro educativo en estudiantes de Educación Media Superior en México. El estudio fue no experimental, descriptivo y correlacional con una muestra de 7,568 estudiantes que presentaron la prueba pisa 2015, en los 32 estados de la República Mexicana. Se construyó un modelo teórico a través de ecuaciones estructurales, considerando los enfoques humanista y sistémico. Los resultados muestran que existen asociaciones positivas del logro educativo con los factores: el uso tecnológico, ambiente escolar, autosuperación, dedicación escolar, profesor constructor, apoyos de padres/madres, y aprendizaje colaborativo; así como asociaciones negativas con: el ausentismo, disregulación emocional y profesor dominante. El modelo empírico construido muestra otras asociaciones: profesor constructor y mejor ambiente escolar; profesor limitador y ausentismo; disregulación emocional y falta de autosuperación. En conclusión, se propone la integración tecnológica, la transformación docente, la sinergia formativa y la activación de centros psicopedagógicos.

This paper describes the design and construction of a prototype equipment for measuring homogeneous magnetic Þ eld with working frequency sinusoidal 60 Hz, using as the main tool hall effect sensor.The meter has three stages of construction, patterns hall effect sensor, microcontroller programming and screen display. The employer has two stages, gating power to the Helmholtz coil and calibration of the Hall Effect sensor. The final part is the simulation of the magnetic field performance verification COMSOL as both a generatorand the measuring equipment.

In the country there is a great quantity of hanging bridges type pony. This article presents the methodology and the results obtained in a study of the behavior of this type of bridges for the construction and the service loads. Besides, the behavior of the lateral stability of these models.

Ting and Robinson (1998) and Dimmitt (2003) present the need to study the topic of academic success including psychosocial aspects of the pupils. The objective of this research was to describe the psychosocial profile and the use of the Information and Communication Technologies (ICTs) of undergraduate students. The research design used for this purpose was non-experimental transectional descriptive. The instruments were a questionnaire for the Integral Profile of the Student and the Gordon Personal Profile Inventory. The sample consisted of 469 Mexican undergraduate pupils who receive traditional education. The results show that there is a significant difference statistically speaking according to the p value (0.000; 0.025; 0.004.000) obtained in the ANOVA for the cognitive and emotional areas, use of the ICTs and self-esteem of the surveyed students with high GPA.