55 research outputs found

    A non-linear model for forecasting the monthly demand for electricity in Colombia

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    ABSTRACT This article provides a comparison of the performance of an ARIMA model, a multilayer perceptron, and an autoregressive neural network for forecasting the monthly demand for electricity in Colombia for the following month. The available data were divided into two different sets, i.e. one set for estimating the model parameters, and the other for evaluating the forecast ability outside the range of the sample calibration data. The results show that the autoregressive neural network is able to forecast the demand more accurately than the other two models when the total available data are considered.

    Smart meters adoption: recent advances and future trends

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    High growth in electricity demand and peaks in the load curve, caused mainly by households, require big investments in infrastructure that are used for short periods. Because of this, it is necessary to look for new developments that allow meeting the needs of users as well as using the electricity system resources efficiently. This is possible through the Smart Grid (SG), which additionally allows users to have autonomy in the electricity supply chain. Our focus of investigation is with households because they can monitor their demand and help to reduce the peaks of the load curve. To do this, users must use Smart Meters, because these devices allow consumers to obtain the information necessary to control their demand. This paper presents a systematic analysis of published literature related to the study of the SG from the demand side, analyses the current situation of this topic and the impact of Smart Meter penetration in households

    Análisis y predicción de series de tiempo en mercados de energía usando el lenguaje r

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    El análisis de series de tiempo y la predicción de variables económicas son tópicos centrales de investigación en el campo de la energía. En este artículo, se revisan los principales aspectos del lenguaje R para el computó estadístico, y se discute su utilidad potencial para los investigadores y profesionales en mercados de energía. También, se revisan las principales funciones disponibles para el análisis de series de tiempo y se presentan algunos ejemplos de su uso

    Time series analysis and forecasting in energy markets using the R language.

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    El análisis de series de tiempo y la predicción de variables económicas son tópicos centrales de investigación en el campo de la energía. En este artículo, se revisan los principales aspectos del lenguaje R para el computó estadístico, y se discute su utilidad potencial para los investigadores y profesionales en mercados de energía. También, se revisan las principales funciones disponibles para el análisis de series de tiempo y se presentan algunos ejemplos de su uso./ Abstract: Time series analysis and forecasting of economic variables are central research topics in the energy field. In this paper, we review the main aspects of the R language for statistical computing, and we stress the potential usefulness for researchers and practitioners of energy markets. Also, we review the main available functions for time series analysis and forecasting, and we present some example of their use

    Avances recientes en la predicción de la demanda de electricidad usando modelos no lineales

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    La predicción de la demanda es un problema de gran importancia para el sector eléctrico, ya que a partir de sus resultados, los agentes del mercado de energía toman las decisiones más adecuadas para su labor. En este artículo se presenta un análisis de las técnicas y modelos más usados en el pronóstico de la demanda de electricidad y la problemática o dificultades a las que se enfrentan los investigadores al momento de realizar un pronóstico. El análisis muestra que las técnicas más usadas son los modelos ARIMA y las redes neuronales artificiales. Sin embargo, se encontró poca claridad sobre cuál modelo es más adecuado y en qué casos, adicionalmente, los estudios no presentan una recomendación específica para desarrollar modelos de pronóstico de demanda, específicamente en el caso colombiano. Finalmente, se propone realizar un estudio sistemático con el fi n de determinar los modelos más adecuados para predicción de demanda para el caso colombiano

    Artritis reumatoide temprana

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    Early Reumathoid Arthritis.The classic diagnosis of rheumatoid arthritis by American College of Rheumatology criteria is insensitive for detecting early disease. If rheumatoid arthritis is diagnosed early, disease remission and prevention of radiological progression can be quickly achieved, with marked impact on mortality and quality of life of patients. The clinical involvement of metacarpophalangeal and metatarsophalangeal joints, morning stiffness more than 30 minutes and anti-cyclic citrullinated peptide antibodies, together with imaging methods like magnetic resonance imaging and ultrasound, constitute fundamental pillars of early diagnosis. Early treatment with disease-modifying antirrheumatic drugs and biological therapy can achieve clinical status close to non-disease. Key Words: Early diagnosis. Rheumatoid Arthritis. Therapeutics.El diagnóstico clásico de artritis reumatoide por los criterios del Colegio Americano de Reumatología es poco sensible para la detección de enfermedad temprana. Si la artritis reumatoide es diagnosticada precozmente puede lograrse con rapidez la remisión de la enfermedad y evitar su progresión radiológica, con impacto marcado en la mortalidad y en la calidad de la vida de los pacientes. El compromiso clínico de las articulaciones metacarpofalángicas y metatarsofalángicas, la rigidez matinal de 30 minutos y los anticuerpos anti-péptidos cítricos citrulinados, junto con métodos imagenológicos como la resonancia magnética y el ultrasonido, se constituyen en pilares fundamentales de diagnóstico temprano. Un tratamiento precoz con drogas modificadoras o terapia biológica pueden lograr un estado clínico cercano a la curación. Palabras Clave: Diagnóstico Temprano. Artritis Reumatoide. Terapéutica. &nbsp

    Cutaneous manifestations of early systemic lupus erythematosus and correlation with systemic activity

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    RESUMEN: Las manifestaciones cutáneas del lupus eritematoso sistémico (LES) son heterogéneas (específicas e inespecíficas). Poco se sabe acerca de la relación entre estas manifestaciones y la actividad clínica e inmunológica de la enfermedad en sus etapas iniciales. Se llevó a cabo un estudio de corte transversal en 34 pacientes con LES temprano. Se encontró una asociación significativa entre alopecia e hipocomplementemia C3 (p = 0,021), hipocomplementemia C4 (p < 0,001) y anti-Sm (p = 0,011); entre eritema malar y anti-Ro (p = 0,037) y anti-La (p = 0,037); entre fotosensibilidad y anti-RNP (p = 0,037). Se observó una tendencia a la asociación entre úlceras orales e hipocomplementemia C4 (p = 0,064). No hubo asociación entre las manifestaciones cutáneas y la presencia de anti-ADN de doble cadena (anti-ds ADN), anticuerpos anticardiolipinas, anticoagulante lúpico, VDRL falso positivo, leucopenia, trombocitopenia, hipergammaglobulinemia, elevación de la velocidad de sedimentación globular o SLEDAI. Se resalta la importancia de la relación entre las manifestaciones cutáneas inespecíficas de LES (alopecia y fotosensibilidad) y la actividad sistémica en pacientes con enfermedad temprana y la clara asociación de estas con hipocomplementemia, un marcador importante de actividad inmunológica.ABSTRACT: Cutaneous manifestations of systemic lupus erythematosus (SLE) are heterogeneous (both specific and non-specific). Little is known about the relationship between these manifestations and the clinical and immunological activity of the disease in early stages. We carried out a cross-sectional study in 34 patients with early SLE. We found a significant association between alopecia and hypocomplementemia C3 (p = 0.021), hypocomplementemia C4 (p < 0.001) and anti-Sm (p = 0.011); between malar erythema and anti-Ro (p = 0.037) and anti-La (p = 0.037); between photosensitivity and anti-RNP (p = 0.037). We observed a trend to association between oral ulcers and hypocomplementemia C4 (p = 0.064). No association was found between cutaneous manifestations and the presence of anti-ds DNA, anticardiolipin antibodies, lupus anticoagulant, false-positive VDRL, leucopenia, thrombocytopenia, hypergammaglobulinemia, elevated erythrosedimentation rate or SLEDAI. We highlight the relevance of the relationship between non-specific cutaneous manifestations of early SLE (alopecia and photosensitivity) and the systemic activity of the disease and hypocomplementemia, an important marker of immunological activity

    Caracterización de pacientes con artritis indiferenciada y evolución a otras enfermedades inflamatorias en una cohorte del noroccidente colombiano: Estudio observacional.

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    Introduction: Undifferentiated arthritis is an inflammatory arthropathy that does not meet the criteria of specific rheumatological diseases and whose symptoms persist for one year. These individuals may spontaneously remit or evolve to another defined arthropathy, especially rheumatoid arthritis. The aim of this study was to describe the clinical and laboratory characteristics, both baseline and follow-up, of patients with undifferentiated arthritis in a reference center. Materials and methods: A retrospective descriptive study was conducted with patients with undifferentiated arthritis defined by rheumatologist criteria. Sociodemographic, clinical and therapeutic variables were analyzed. The qualitative variables were expressed as absolute and relative frequencies and the quantitative variables with median and interquartile range. Results: 66 patients were included; the median age was 46.3 years (IQR: 37.5-51.8); 10 subjects (15.2%) had a family history of rheumatoid arthritis. Forty individuals (60.6%) had involvement in proximal interphalangeal joints; the main symptom was morning stiffness in 29 patients (44%). The most frequent extra-articular involvement was cutaneous (n = 14, 21.2%). Non-steroidal anti-inflammatory drugs (n=18; 27.2%) and steroids (n=15; 22.7%) were the most frequent treatments. Of 43 patients, 22 (51.2%) remained with a diagnosis of undifferentiated arthritis, 18 (41.9%) progressed to other diseases, the most frequent being rheumatoid arthritis, and in three (7%) there was disease remission. Conclusions: In a cohort of patients with undifferentiated arthritis from northwestern Colombia, after 12 months, most of them persist with this diagnosis; it was striking the important frequency of a family history of rheumatoid arthritis and a low spontaneous remission.Introducción: La artritis indiferenciada es una artropatía inflamatoria que no cumple con los criterios de enfermedades reumatológicas específicas y cuyos síntomas persisten durante un año. Estos individuos pueden remitir espontáneamente o evolucionar a otra artropatía definida, especialmente artritis reumatoide. El objetivo de este estudio fue describir las características clínicas y de laboratorio, tanto basales como de seguimiento, de pacientes con artritis indiferenciada en un centro de referencia. Materiales y métodos: Se realizó un estudio descriptivo retrospectivo con pacientes con artritis indiferenciada por criterio de reumatólogo. Se analizaron variables sociodemográficas, clínicas y terapéuticas. Las variables cualitativas se expresaron como frecuencias absolutas y relativas, y las cuantitativas con mediana y rango intercuartílico. Resultados: Se incluyeron 66 pacientes; la mediana de edad fue 46,3 años (RIC: 37,5-51,8); diez (15,2%) sujetos tenían antecedente familiar de artritis reumatoide. Cuarenta (60,6%) individuos tuvo compromiso articular en interfalángicas proximales; el principal síntoma fue la rigidez matinal en 29 pacientes (44%). El compromiso extraarticular más frecuente fue el cutáneo (n=14; 21,2%). Los antiinflamatorios no esteroideos (n=18; 27,2%) y los esteroides (n=15; 22,7%) fueron los tratamientos más frecuentes. De 43 pacientes, 22 (51,2%) permanecieron con diagnóstico de artritis indiferenciada, 18 (41,9%) progresaron a otras enfermedades, siendo la más frecuente artritis reumatoide y en tres (7%) hubo remisión. Conclusiones: En una cohorte de pacientes con artritis indiferenciada del noroccidente colombiano, luego de 12 meses, en su mayoría, persisten con este diagnóstico; fue llamativa la frecuencia importante de antecedente familiar de artritis reumatoide y de baja remisión espontánea

    The Research Journey as a Challenge Towards New Trends

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    The academic community of the department of Risaralda, in its permanent interest in evidencing the results of the research processes that are carried out from the Higher Education Institutions and as a product of the VI meeting of researchers of the department of Risaralda held in November 2021 presents its work: “The journey of research as a challenge towards new trends”, which reflects the result of the latest research and advances in different lines of knowledge in Agricultural Sciences, Health Sciences, Social Sciences and Technology and Information Sciences, which seek to solve and meet the demands of the different sectors. This work would not have been possible without the help of each of the teachers, researchers and authors who presented their articles that make up each of the chapters of the book, to them our gratitude for their commitment, dedication and commitment, since their sole purpose is to contribute from the academy and science to scientific and technological development in the search for the solution of problems and thus contribute to transform the reality of our society and communities. We also wish to extend our gratitude to the institutions of the Network that made this publication possible: UTP, UCP, UNAD, UNIREMINGTON; UNISARC, CIAF, Universidad Libre, Uniclaretiana, Fundación Universitaria Comfamiliar and UNIMINUTO, institutions that in one way or another allowed this work to become a reality, which we hope will be of interest to you.Preface............................................................................................................................7 Chapter 1. Technologies and Engineering Towards a humanization in Engineering using soft skills in training in Engineers.............................................................................................................11 Omar Iván Trejos Buriticá1, Luis Eduardo Muñoz Guerrero Innovative materials in construction: review from a bibliometric analysis....................................................................................................................27 Cristian Osorio Gómez, Daniel Aristizábal Torres, Alejandro Alzate Buitrago, Cristhian Camilo Amariles López Bibliometric review of disaster risk management: progress, trends, and challenges.........................................................................................................51 Alejandro Alzate Buitrago, Gloria Milena Molina Vinasco. Incidence of land coverage and geology, in the unstability of lands of the micro-basin of the Combia creek, Pereira, Risaralda....................................73 Alejandro Alzate Buitrago, Daniel Aristizábal Torres. Chapter 2. Arts, Humanities, and Social Sciences Training experience with teachers teaching mathematics using the inquiry methodology ...............................................................................................95 Vivian Libeth Uzuriaga López, Héctor Gerardo Sánchez Bedoya. Interpretation of the multiple representations of the fears associated to the boarding of limited visual patients in the elective I students’ written productions and low vision ...................................................................................113 Eliana Bermúdez Cardona, Ana María Agudelo Guevara, Caterine Villamarín Acosta. The relevance of local knowledge in social sciences............................................131 Alberto Antonio Berón Ospina, Isabel Cristina Castillo Quintero. Basic education students’ conceptions of conflict a view from the peace for the education....................................................................................................143 Astrid Milena Calderón Cárdenas,Carolina Aguirre Arias, Carolina Franco Ossa, Martha Cecilia Gutiérrez Giraldo, Orfa Buitrago. Comprehensive risk prevention in educational settings: an interdisciplinary and socio-educational approach ............................................................................163 Olga María Henao Trujillo, Claudia María López Ortiz. Chapter 3. Natural and Agricultural Sciences Physicochemical characterization of three substrates used in the deep bedding system in swine .......................................................................................175 Juan Manuel Sánchez Rubio, Andrés Felipe Arias Roldan, Jesús Arturo Rincón Sanz, Jaime Andrés Betancourt Vásquez. Periodic solutions in AFM models........................................................................187 Daniel Cortés Zapata, Alexander Gutiérrez Gutiérrez. Phenology in flower and fruit of Rubus glaucus benth. Cv. Thornless in Risaralda: elements for phytosanitary management .........................................199 Shirley Palacios Castro, Andrés Alfonso Patiño Martínez, James Montoya Lerma, Ricardo Flórez, Harry Josué Pérez. Socio-economic and technical characterization of the cultivation of avocado (Persea americana) in Risaralda..............................................................217 Andrés Alfonso Patiño Martínez, Kelly Saudith Castañez Poveda, Eliana Gómez Correa. Biosecurity management in backyard systems in Santa Rosa de Cabal, Risaralda................................................................................................................227 Julia Victoria Arredondo Botero, Jaiver Estiben Ocampo Jaramillo, Juan Sebastián Mera Vallejo, Álvaro de Jesús Aranzazu Hernández. CONTENTS Physical-chemical diagnosis of soils in hillside areas with predominance of Lulo CV. La Selva production system in the department of Risaralda.............241 Adriana Patricia Restrepo Gallón, María Paula Landinez Montes, Jimena Tobón López. Digestibility of three concentrates used in canine feeding....................................271 María Fernanda Mejía Silva, Valentina Noreña Sánchez, Gastón Adolfo Castaño Jiménez. Chapter 4. Economic, Administrative, and Accounting Sciences Financial inclusion in households from socioeconomic strata 1 and 2 in the city of Pereira ..................................................................................................285 Lindy Neth Perea Mosquera, Marlen Isabel Redondo Ramírez, Angélica Viviana Morales. Internal marketing strategies as a competitive advantage for the company Mobilautos SAS de Dosquebradas........................................................................303 Inés Montoya Sánchez, Sandra Patricia Viana Bolaños, Ana María Barrera Rodríguez. Uses of tourist marketing in the tourist sector of the municipality of Belén de Umbría, Risaralda.............................................................................................319 Ana María Barrera Rodríguez, Paola Andrea Echeverri Gutiérrez, María Camila Parra Buitrago, Paola Andrea Martín Muñoz, Angy Paola Ángel Vélez, Luisa Natalia Trejos Ospina. Territorial prospective of Risaralda department (Colombia), based on the SDGS...............................................................................................................333 Juan Guillermo Gil García, Samanta Londoño Velásquez. Chapter 5. Health and Sports Sciences Performance evaluation in times of pandemic. What do medical students think?.......................................................................................................353 Samuel Eduardo Trujillo Henao, Rodolfo A. Cabrales Vega, Germán Alberto Moreno Gómez. The relevance of the therapist’s self and self-reference in the training of psychologists.....................................................................................................371 Maria Paula Marmolejo Lozano, Mireya Ospina Botero. Habits related to oral health which influence lifestyle of elder people in a wellness center for the elderly in Pereira 2020. .............................................387 Isadora Blanco Pérez, Olga Patricia Ramírez Rodríguez, Ángela María Rincón Hurtado. Analysis of the suicide trend in the Coffee Region in Colombia during the years 2012-2018 ..............................................................................................405 Germán Alberto Moreno Gómez, Jennifer Nessim Salazar, Jairo Franco Londoño, Juan Carlos Medina Osorio. Hind limb long bone fractures in canines and felines...........................................419 María Camila Cruz Vélez, Valentina Herrera Morales, Alba Nydia Restrepo Jiménez, Lina Marcela Palomino, Gabriel Rodolfo Izquierdo Bravo. Prevalence of overweight and obesity in children in the rural and urban area of Risaralda....................................................................................................439 Angela María Álvarez López, Angela Liceth Pérez Rendón, Alejandro Gómez Rodas, Luis Enrique Isaza Velásquez. Chapter 6. Architecture, Design and Advertising The artisan crafts of Risaralda, characteristics, importance, and risks within the Colombian Coffee Cultural Landscape, CCCL....................................457 Yaffa Nahir Ivette Gómez Barrera, Javier Alfonso López Morales

    Pronóstico de series de tiempo con tendencia y ciclo estacional usando el modelo airline y redes neuronales artificiales

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    Many time series with trend and seasonal pattern are successfully modeled and forecasted by the airline model of Box and Jenkins; however, this model neglects the presence of nonlinearity on data. In this paper, we propose a new nonlinear version of the airline model; for this, we replace the moving average linear component by a multilayer perceptron neural network. The proposed model is used for forecasting two benchmark time series; we found that the proposed model is able to forecast the time series with more accuracy that other traditional approaches.Muitas s´eries temporais com tend�encia e sazonalidade s�ao sucesso modelado e previsto pelo modelo airline de Box e Jenkins, no entanto, este modelo negligencia a presen¸ca de n�ao-linearidade dos dados. Neste trabalho, propomos uma nova vers�ao n�ao-linear do modelo airline, por isso, substituir o componente linear das medias moviles por um perceptron multicamadas. O modelo propostoe utilizado para previsao de duas series temporais de referencia; descobrimos que o modelo proposto ´e capaz de prever a s´erie de tempo com mais precis�ao que outros m´etodos tradicionais.Muchas series de tiempo con tendencia y ciclos estacionales son exitosamente modeladas y pronosticadas usando el modelo airline de Box y Jenkins; sin embargo, la presencia de no linealidades en los datos son despreciadas por este modelo. En este art´ýculo, se propone una nueva versi´on no lineal del modelo airline; para esto, se reemplaza la componente lineal de promedios m´oviles por un perceptr´on multicapa. El modelo propuesto es usado para pronosticar dos series de tiempo benchmark; se encontr´o que el modelo propuesto es capaz de pronosticar las series de tiempo con mayor precisi´on que otras aproximaciones tradicionales
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