Diseño y construcción de un generador de impulso de voltaje de 10 KV

En este articulo se presenta el diseño y construcción de un generador de impulso de voltaje tipo rayo de 10 kV desarrollado en la Universidad del Valle. El generador se concibió con fines académicos y se construyo para que permitiera un fácil entendimiento del principio de funcionamiento del generador de un generador multietapastipo Marx. Los requerimientos para este generador incluyeron portabilidad, modularidad, y que sus elementos de construcción fueran comerciales y de bajo costo. El diseño y la construcción incluyeron las etapas de potencia, la fuente de alimentación, el sistema de control de ignición y un divisor capacitivo amortiguado para la medición de las ondas generadas. Para el diseño se empleo la herramienta OrCAD y la validación de su funcionamiento se realizo mediante pruebas de laboratorio de alta tensión de la Universidad del Valle

MECHANICAL PROPERTIES OF CLASS H CEMENT AT ROOM AND ELEVATED TEMPERATURES AND THE EFFECT OF GILSONITE AND MICROCELLULOSE ON ITS MECHANICAL PROPERTIES

With an increase in global energy demands, the importance of well integrity and the oilfield cements has become more important than ever as it guarantees the continuous supply of fossil fuel to fulfill the requirement of the world. Drilling operations in recent years have gone into much deeper depths to meet the global demands in hydrocarbons, geothermal, gas storage and carbon sequestration purposes. In well integrity, cement plays a crucial role as it seals/isolates the troublesome formation or thief zone meanwhile protect the casing from corrosion and giving structural support to it. Therefore, it is necessary that cement slurry characteristics should be designed according to the subsurface environment, thus a proper characterization of the mechanical properties of cement in the laboratory is mandatory get to know its behavior when exposed to downhole conditions, and cubes and cylinders are the most commonly used shapes to characterized the mechanical properties, nevertheless, American Petroleum Institute (API) does not have a recommendation for cylinders, moreover, a review of American Society for Testing and Materials (ASTM) and British standards (BS) for the UCS is given, hence a study to determine if a correlation between cubes and cylinders can be achieved is studied. Though there are many conventional additives in the market but unconventional additives like Gilsonite and Microcellulose is not extensively studied. Gilsonite is a naturally occurring additive that is derived from hydrocarbons classified as asphaltite. It has been used in water-based drilling fluid and sometimes with an oil base mud as a treatment for filtration and sloughing shale problems. Given the useful properties of Gilsonite such as impermeability, low specific gravity and its great corrosive and acidic resistance it has been used as a loss of circulation material in cement applications. Micro-cellulose (MC) has been reported as a great additive in geothermal well fluid loss curing solutions. Given the recent success of using Micro-Cellulose in curing loss circulation and providing Wellbore Strengthening, addition of some amount to the cement slurry could inevitably be an option for cement fluid loss cure. However, the Micro-Cellulose can change the hydration process on the cement due to its natural characteristics, decreasing the compressive strength of the cement at the early stages; this phenomenon will be further described in the paper This paper shows the results of more than 100 tests conducted on cement cubes and cylinders to determine if a correlation between cubes and cylinders can be obtained, cubes and cylinders samples of class H cement at room and elevated temperature were prepared, and an investigation of more than 500 test was performed to show the effect of age (up to 120 days) and temperature (23c and 75c) on class H neat, H + 4% Microcellulose and 4% Gilsonite to investigate the effect of those additives in the mechanical properties of the cement. It was observed that variation in the results existed in the UCS when cubes are compared with the cylinder, which raises the importance of the development of the new standard. The results showed the high compressive strength of the cube as much as 50% and 35% for the sample cured at high and room temperature respectively. Moreover, no correlation existed between the cylinder cured at high temperature and UCS or UPV. Whereas the cube sample was able to give a logarithmic or exponential correlation for all the testing scenarios. Hence a better understanding of the cylindrical sample is needed and the data from this research can help to compare the results from these two geometries. This research also focuses on the evaluation of mechanical properties of Gilsonite and Microcellulose (MC) cement composite and compared with neat Class H cement. The compressive strength of the cement is measured through a direct and indirect method. Samples were cured at high temperatures (75°C) and at ambient conditions for the period of 1, 3, 7, 14, 21, 28, 35, 60, 90 and 120 days. It was found that at high temperature (HT) the development of compressive strength in 4% Gilsonite cement composite was very rapid with the UCS going as high as 42MPa within three days of curing. Whereas 4% MC shows an identical behavior as Gilsonite at room temperature, but a decrease in strength at HT when compared to Gilsonite or neat class H cement

Diseño e Implementación de un Instrumento Didáctico para Elaborar Mapas Conceptuales Que Fomente El Desarrollo de Pensamiento de Orden Superior en los Estudiantes de Grado Septimo Y Noveno del Colegio Integral Avancemos (Bogotá D.C.-Colombia)

Teniendo como premisa el logro del aprendizaje significativo mediante el alcance de acciones de pensamiento de orden superior por parte del estudiante, se diseñó y aplicó una secuencia de actividades para dar a conocer la estructura del mapa conceptual, y orientar a los estudiantes de los grados séptimo y noveno del Colegio Avancemos de la localidad de San Cristóbal sur, en la construcción de mapas conceptuales, apartando cada uno de los componentes y características de los mismos, para trabajarlos por separado, lo anterior basado en la teoría de los mapas conceptuales de Novak, las categorías de pensamiento de orden superior de Bloom, y la teoría del aprendizaje significativo de Ausubel. La presente investigación permitió identificar las concepciones alternativas de los estudiantes sobre los mapas conceptuales, para establecer el punto de partida hacia la caracterización de las falencias en los métodos empleados por ellos, en la construcción de los mapas, para luego, poder establecer los parámetros a aplicar en las estrategias que orienten a los estudiantes en la organización de conocimientos, tanto previos como nuevos, en sus estructuras mentales.Teniendo como premisa el logro del aprendizaje significativo mediante el alcance de acciones de pensamiento de orden superior por parte del estudiante, se diseñó y aplicó una secuencia de actividades para dar a conocer la estructura del mapa conceptual, y orientar a los estudiantes de los grados séptimo y noveno del Colegio Avancemos de la localidad de San Cristóbal sur, en la construcción de mapas conceptuales, apartando cada uno de los componentes y características de los mismos, para trabajarlos por separado, lo anterior basado en la teoría de los mapas conceptuales de Novak, las categorías de pensamiento de orden superior de Bloom, y la teoría del aprendizaje significativo de Ausubel. La presente investigación permitió identificar las concepciones alternativas de los estudiantes sobre los mapas conceptuales, para establecer el punto de partida hacia la caracterización de las falencias en los métodos empleados por ellos, en la construcción de los mapas, para luego, poder establecer los parámetros a aplicar en las estrategias que orienten a los estudiantes en la organización de conocimientos, tanto previos como nuevos, en sus estructuras mentales

Seguridad y gestión en arquitecturas ópticas de comunicación de datos

El cambiante escenario telemático, ha permitido la utilización plena de los sistemas de comunicación óptica, para alcanzar así velocidades del orden de los terabits por segundo, cualificando nuevos escenarios operacionales como las SAN y optimizando la potencialidad de la multiplexación por longitud de onda. El paso de PDH a SDH y SONET, deparo una gran ventaja competitiva y funcional, en loa componentes de las capas de la red de transporte: circuito, trayecto y transmisión, al categorizar la calidad de servicio ( Qos) y el Label Switch Path (LSP), como diferenciadores de construcción en el proceso de intercambio de valores son soporte de las SAN, en lo pertinente al direccionamiento, descubrimiento y encaminamiento tanto en redes metropolitanas como en redes de larga distancia, generando el salto operacional del entorno WDM al DWDM. Se presentan en este trabajo, las generalidades del marco de desarrollo, luego se aborda la teoría de la física de la luz, y el nivel operacional de la fibra óptica para entonces poder desarrollar lo pertinente al hardware óptico especializado, redes de acceso, protección, gestión y control

Analysis and Performance of Adhesively Bonded Crush Tube Structures

Lighter structural and energy absorbing materials are essential to increase fuel efficiency in transportation systems and have provided a motivation to investigate the use of new joining techniques based on the use of high strength and high tenacity adhesives. Current joining techniques, such as spot-welding, limit the possible weight reduction that can be achieved if lighter sections, dissimilar materials and/or novel geometries were to be used. Adhesive materials can address many limitations of current joining techniques. To take advantage of the available numerical codes for the simulation of bonded structures during dynamic crash events, a constitutive model for structural adhesive material using cohesive elements was assembled from the measured properties of two structural adhesives; DP-460NS and EC-2214 (3M, Canada). To verify that the proposed cohesive model accurately describes the behavior of the materials a two stage approach was used. First, a cohesive element formulation of the adhesive material was implemented to investigate a Double Cantilever Beam (DCB) (ASTM test D3433-99). The results of the simulation were compared against available experimental data. Second, using sub-size crush tube structures assembled from steel sections that were adhesively bonded, quasi-static and impact events were performed. The results from the experiment were compared against the numerical simulation of the same structure using cohesive elements to describe the adhesive joint. Later, Tie-Breaks were implemented to reduce computational times. Both types of elements successfully represented the adhesive joint and the numerical model of the crush tube was in good agreement with the overall load-displacement behavior of the experimental crush tubes. The use and testing of sub-size structures not only permitted the validation of the numerical models; it also investigated the feasibility of adhesive-only joints in automotive structures that may be exposed to crash scenarios. Sub-sized tubes were used due to equipment capacity limits, but an analysis was undertaken to demonstrate appropriate structural scaling. Even though the results between the experiments and the simulations were in very good agreement, it is clear that current cohesive material models and Tie-Breaks cannot incorporate strain rate effects, which may be important under dynamic impact conditions. Although testing in the literature has reported that the mechanical properties of the bond are affected by the properties of the joined materials as well as the geometry of the joint, these effects in the case of crush tube structures seem perhaps negligible in view of the simulation results

A Novel ARX-Based Approach for the Steady-State Identification Analysis of Industrial Depropanizer Column Datasets

This paper introduces a novel steady-state identification (SSI) method based on the auto-regressive model with exogenous inputs (ARX). This method allows the SSI with reduced tuning by analyzing the identifiability properties of the system. In particular, the singularity of the model matrices is used as an index for steady-state determination. In this contribution, the novel SSI method is compared to other available techniques, namely the F-like test, wavelet transform and a polynomial-based approach. These methods are implemented for SSI of three different case studies. In the first case, a simulated dataset is used for calibrating the output-based SSI methods. The second case corresponds to a literature nonlinear continuous stirred-tank reactor (CSTR) example running at different steady states in which the ARX-based approach is tuned with the available input-output data. Finally, an industrial case with real data of a depropanizer column from PETROBRAS S.A. considering different pieces of equipment is analyzed. The results for a reflux drum case indicate that the wavelet and the F-like test can satisfactorily detect the steady-state periods after careful tuning and when respecting their hypothesis, i.e., smooth data for the wavelet method and the presence of variance in the data for the F-like test. Through a heat exchanger case with different measurement frequencies, we demonstrate the advantages of using the ARX-based method over the other techniques, which include the aspect of online implementation

Características de la Educación Superior en Colombia y de las Universidades Públicas del SUE 2022

En estos momentos en los que como sociedad nos enfrentamos a grandes retos sociales, económicos y científicos, la educación superior se convierte en un desafío a nivel mundial, nacional y local, al que se debe atender con compromiso y constancia, revisando y estudiando permanentemente su labor en todos los campos, para que con base en datos y cifras se puedan formalizar propuestas académicas, sociales, de investigación y de sostenibilidad, encaminadas a una formación pertinente y de alta calidad. Es por esta razón, que como Rector de la Universidad Tecnológica de Pereira presento con satisfacción este documento elaborado desde la Comisión de Vicerrectores administrativos y Financieros del SUE, que desde el seno de nuestra institución y mediante un ejercicio juicioso y técnico compila una información valiosa de todas las Instituciones de Educación Superior en Colombia y del sector, e incluye una caracterización de las Universidades Públicas que conforman el Sistema Universitario Estatal. En este sentido, agradecemos la confianza depositada en el equipo de nuestra alma mater para acompañar y coordinar esta comisión y mantenemos nuestro compromiso en el desarrollo y participación de los diferentes ejercicios que se efectúen al interior del SUE y en particular de los desarrollados por la Comisión de Vicerrectores Administrativos y Financieros.Contenido Agradecimientos ..................................................................................................................................................10 Prólogo ...................................................................................................................................................................12 Presentación ..........................................................................................................................................................14 1 Educación Superior.......................................................................................................................................15 1.1 La Educación Superior en el escenario global...............................................................................15 1.2 La Educación Superior en Colombia................................................................................................17 1.2.1 Datos de cobertura en Educación Superior en Colombia...........................................................21 1.2.2 Personal docente .................................................................................................................................33 1.2.3 Calidad en el sistema de Educación Superior............................................................................... 40 1.2.4 Datos de la evolución de los procesos de investigación.............................................................47 1.2.5 Procesos de internacionalización y movilidad académica........................................................ 50 1.2.6 Condiciones económicas de la población estudiantil .................................................................51 1.2.7 Deserción en matrícula.......................................................................................................................53 2 Sistema Universitario Estatal (SUE).........................................................................................................56 2.1 Integrantes del Sistema Universitario Estatal................................................................................56 2.2 Reglamentación y estructura interna..............................................................................................59 2.3 Evolución de las Universidades del SUE. ........................................................................................61 2.3.1 Cobertura estudiantil y programas académicos. .........................................................................61 2.3.2 Datos sobre deserción estudiantil....................................................................................................68 2.3.3 Planta docente y niveles de formación. ..........................................................................................69 2.3.4 Fortalecimiento de la Investigación.................................................................................................74 2.3.5 Procesos de internacionalización y movilidad académica.........................................................78 2.3.6 Infraestructura física...........................................................................................................................79 2.4 Financiación Universidades Públicas............................................................................................. 80 3 Descripción de las Universidades Públicas que integran el SUE ....................................................8

Influencing over people with a social emotional model

[EN] This paper presents an approach of a social emotional model, which allows to extract the social emotion of a group of intelligent entities. The emotional model PAD allows to represent the emotion of an intelligent entity in 3-D space, allowing the representation of different emotional states. The social emotional model presented in this paper uses individual emotions of each one of the entities, which are represented in the emotional space PAD. Using a social emotional model within intelligent entities allows the creation of more real simulations, in which emotional states can influence decision-making. The result of this social emotional mode is represented by a series of examples, which are intended to represent a number of situations in which the emotions of each individual modify the emotion of the group. Moreover, the paper introduces an example which employs the proposed model in order to learn and predict future actions trying to influence in the social emotion of a group of people.This work is partially supported by the MINECO/FEDER TIN2015-65515-C4-1-R and the FPI grant AP2013-01276 awarded to Jaime-Andres Rincon.Rincon, J.; De La Prieta-Pintado, F.; Zanardini, D.; Julian Inglada, VJ.; Carrascosa Casamayor, C. (2017). Influencing over people with a social emotional model. Neurocomputing. 231:47-54. https://doi.org/10.1016/j.neucom.2016.03.107S475423