ABSTRACT
This paper proposes an approach to the real time simulation of photovoltaic (PV) arrays that are subjected to mismatching conditions, e.g. partial shadowing. The method, which has been named Model by Zone (MbZ), adopts the best PV model depending on the operating conditions of the cells in the module: it switches among single-diode model (SDM), linear model and constant voltage model. An optimized digital hardware architecture exploiting parallelism of operations over a FPGA system is exploited to effectively implement the proposed model. It reduces the computation time and the use of hardware resources. The good trade-off between accuracy and computation time of the proposed technique has been demonstrated in two cases of study: by evaluating the long-term PV power production of a PV field subjected to dynamic shadowing conditions and by analyzing the model performance in a maximum power point tracking (MPPT) application. In the former case, the proposed approach improves the computation time by 182.5 % with respect to methods that are available in recent literature, with a Relative Error (RE) at the Global Maximum Power Point (GMPP) lower than 0.39 % . In the MPPT application, the proposed technique allows to achieve a MAPE of 0.0319 % and 0.1892 % in the string voltage and power calculation, respectively.
ABSTRACT
El desarrollo de la profesión de la instrumentación quirúrgica en el país ha estado vinculado con la organización de la prestación de servicios de salud y en particular con la práctica médica quirúrgica. Así mismo, se ha sincronizado con los avances en protección específica, nuevas vacunas, y con las innovaciones en bioseguridad y vigilancia epidemiológica en el entorno hospitalario. Estas nuevas realidades plantean diversas exigencias para la formación del Instrumentador Quirúrgico.
Subject(s)
Humans , Allied Health Personnel , Schools, Medical , Colombia , Intraoperative CareABSTRACT
We report the results of a retrospective, descriptive, qualitative study of suicide among university students in Bogotá, Colombia. The objective of this study was to document the magnitude, principal characteristics, and impact of this phenomenon in the selected population. A semi-structured survey was employed to collect information from 66 individuals linked to the universities. A total of 45 cases of suicide were documented in the study period (2004 - 2014). Of these, 69% occurred in males and 31% in females. The age range was 17 - 27 years, with 62% of the cases in the 19 - 22 year-old group. The most common mechanisms employed were suffocation and poisoning, followed by intentional falls, use of a firearm, and drug overdose. The selected location was the place of residence in 52% of cases and the university campus in 16% of cases. The distribution of students by area of knowledge showed a predominance of social and human science (44%) followed by engineering (22%). A history of difficulties in family and affective relationships was common among victims, as was a history of exposure to intolerance of differences in sexual orientation. The individuals surveyed expressed a wide range of interpretations of the significance of suicide, both positive (courage, self-affirmation, autonomy) and negative (defeat, despair, and an inability to adapt).
Subject(s)
Interpersonal Relations , Students/statistics & numerical data , Suicide/statistics & numerical data , Adolescent , Adult , Colombia/epidemiology , Female , Humans , Male , Retrospective Studies , Students/psychology , Universities , Young AdultABSTRACT
Resumen Estudio cualitativo, exploratorio, descriptivo y retrospectivo en cinco universidades de Bogotá, Colombia, para conocer la magnitud, las principales características y significados y el impacto del suicidio de estudiantes universitarios. Se realizaron 66 entrevistas semiestructuradas a personal institucional. Se identificaron 45 casos de suicidio consumado en el período 2004 - 2014. El 69% de los casos fueron hombres y el 31% mujeres. El rango de edad estuvo entre 17 y 27 años; 62% entre 19 y 22 años. Las formas más frecuentes de cometer el suicidio fueron el ahorcamiento y el envenenamiento, seguidos del lanzamiento al vacío, el uso de armas de fuego y el consumo de sustancias psicoactivas. El 52% de los casos eligió el lugar de residencia para cometer el hecho; el 16% eligió el campus universitario. Áreas de conocimiento: el 44% pertenecía a ciencias sociales y humanas y el 22% a ingenierías. Motivos y procesos desencadenantes del suicidio identificados, el principal grupo se relaciona con lo familiar, en especial desintegración familiar, ruptura de relaciones de pareja e intolerancia a opciones sexuales diferentes. Los entrevistados expresaron diversos significados del suicidio, tanto positivos: acto de valor y ejercicio de la autonomía, como negativos: impotencia, desadaptación y derrota.
Abstract We report the results of a retrospective, descriptive, qualitative study of suicide among university students in Bogotá, Colombia. The objective of this study was to document the magnitude, principal characteristics, and impact of this phenomenon in the selected population. A semi-structured survey was employed to collect information from 66 individuals linked to the universities. A total of 45 cases of suicide were documented in the study period (2004 – 2014). Of these, 69% occurred in males and 31% in females. The age range was 17 – 27 years, with 62% of the cases in the 19 – 22 year-old group. The most common mechanisms employed were suffocation and poisoning, followed by intentional falls, use of a firearm, and drug overdose. The selected location was the place of residence in 52% of cases and the university campus in 16% of cases. The distribution of students by area of knowledge showed a predominance of social and human science (44%) followed by engineering (22%). A history of difficulties in family and affective relationships was common among victims, as was a history of exposure to intolerance of differences in sexual orientation. The individuals surveyed expressed a wide range of interpretations of the significance of suicide, both positive (courage, self-affirmation, autonomy) and negative (defeat, despair, and an inability to adapt).
