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Los sistemas cognitivos artificiales en la ense？anza de la matemática
Toro-Carvajal,Luis Alberto; Ortíz-Alvarez,Hugo Hernán; Jiménez-García,Francy Nelly; Agudelo-Calle,Jairo de Jesús;
Educación y Educadores , 2012,
Abstract: the use of artificial cognitive systems (acs) in processes for teaching-learning mathematics is proposed in this article. the theoretical justification for that implementation is based on a view of mathematics and the teaching mathematics as sciences and the cognitive sciences, from which the so-called computational representational model of mathematics (mcrmath) has emerged. this model of mathematics shows why mathematics teaching and learning can and should be mediated by artificial cognitive systems, which are to be understood as tools for cognitive reorganization. an understanding of the knowledge produced through the use of tools provided by artificial cognitive systems is important to the teaching mathematics. the software licensed as matlab and mathcad was used in the examples presented in this study.
Los sistemas cognitivos artificiales en la ense anza de la matemática Os sistemas cognitivos artificiais no ensino da matemática Artificial Cognitive Systems in Teaching Mathematics
Luis Alberto Toro-Carvajal,Hugo Hernán Ortíz-Alvarez,Francy Nelly Jiménez-García,Jairo de Jesús Agudelo-Calle
Educación y Educadores , 2012,
Abstract: Este artículo presenta la implementación de los sistemas cognitivos artificiales (SCA) en los procesos de ense anza-aprendizaje de las matemáticas. La justificación teórica de tal implementación se hace desde el punto de vista de la Matemática y la Educación Matemática como ciencias y la Ciencia Cognitiva, de las cuales emerge el Modelo Computacional-Representacional de la Matemática (MCRMAT). Este modelo de las matemáticas da cuenta del porqué los procesos de ense anza-aprendizaje de las matemáticas pueden y deben ser mediados mediante los sistemas cognitivos artificiales, que deben ser entendidos como herramientas de reorganización cognitiva. La comprensión que se alcance sobre el conocimiento producido con la mediación de las herramientas proporcionadas por los sistemas cognitivos artificiales es importante para la ense anza de la matemática. En los ejemplos que se presentan en este trabajo se ha empleado software licenciado como Matlab y Mathcad. Este artigo apresenta a implementa o dos sistemas cognitivos artificiais (SCA) nos processos de ensino-aprendizagem da matemática. A justificativa teórica dessa implementa o se faz sob o ponto de vista da Matemática e da Educa o Matemática como ciências e a Ciência Cognitiva, das quais emerge o Modelo Computacional-Representacional da Matemática (MCRMAT). Esse modelo da matemática dá conta de por que os processos de ensino-aprendizagem da matemática podem e devem ser mediados pelos sistemas cognitivos artificiais, que devem ser entendidos como ferramentas de reorganiza o cognitiva. A compreens o que se atinge sobre o conhecimento produzido com a media o das ferramentas proporcionadas pelos sistemas cognitivos artificiais é importante para o ensino da matemática. Nos exemplos que se apresentam neste trabalho, empregou-se o software licenciado como Matlab e Mathcad. The use of artificial cognitive systems (ACS) in processes for teaching-learning mathematics is proposed in this article. The theoretical justification for that implementation is based on a view of mathematics and the teaching mathematics as sciences and the cognitive sciences, from which the so-called Computational Representational Model of Mathematics (MCRMATH) has emerged. This model of mathematics shows why mathematics teaching and learning can and should be mediated by artificial cognitive systems, which are to be understood as tools for cognitive reorganization. An understanding of the knowledge produced through the use of tools provided by artificial cognitive systems is important to the teaching mathematics. The software licensed as M
Ionic Composition in Aqueous Extracts from PM2.5 in Ambient Air at the City of Cuernavaca, México  [PDF]
Hugo Saldarriaga-Nore？a, Leonel Hernández-Mena, Enrique Sánchez-Salinas, Fernando Ramos-Quintana, Laura Ortíz-Hernández, Rodrigo Morales-Cueto, Vanesa Alarcón-González, Sandra Ramírez-Jiménez
Journal of Environmental Protection (JEP) , 2014, DOI: 10.4236/jep.2014.513124
Abstract: The present study was carried out between May and June 2012 in the city of Cuernavaca, Mexico. During this time the average ambient temperatures were about 25°C, suggesting the formation of secondary aerosols, consisting mainly of ammonium and sulfate. The average PM2.5 concentration was 37 μg·m-3 for the entire urban area and there were only two days which exceeded the limit established by the official standards for periods of 24 h. The most abundant ionic species associated with PM2.5 were sulfates (3634.82 ng·m-3, average) and ammonium (1709.53 ng·m-3, average). The ratio estimated between total anions and total cations indicated that the concentration of total anions was 1.94 times total cations. The contribution percentage of the ionic species associated with PM2.5 revealed that 76% of the PM2.5 is sulfates and ammonium. The ion balance made for the urban area of Cuernavaca indicated that during the study period, the aerosols showed alkaline characteristics; that is to say the concentration of anions was not sufficient to neutralize the cations, specifically ammonia (m = 0.060). Finally, wind fields showed that during the study the winds came in 50% from the south west, followed by 25% from east and 12.5% of the south east, which in part allowed transport of contaminants into the portion of the city, where the AUSM campus site was located.
Effect of cerebrolysin on dopaminergic neurodegeneration of rat with oxidative stress induced by 3-nitropropionic acid
ATTILUS, JONAS,BRIZUELA, NORMA OSNAYA,GUZMáN, DAVID CALDERóN,HERNáNDEZ GARCíA, ERNESTINA,HERRERA, MARIBEL ORTíZ,MEJíA, GERARDO BARRAGáN,OLGUíN, HUGO JUáREZ,PERAZA, ARMANDO VALENZUELA,RUíZ, NORMA LABRA
- , 2016, DOI: 10.1515/acph-2016-0027
Abstract: Sa？etak The study tested the hypothesis that cerebrolysin protects the brain from free radicals in rats treated with 3-nitropropionic acid (3-NPA). To address this hypothesis, the levels of dopamine (DA) and some oxidative stress biomarkers were measured after administration of 3-NPA. Young male Fischer rats were treated for three days with cerebrolysin, 3-NPA or both substances. Their brains were extracted, and DA, lipid peroxidation (LP), glutathione (GSH), calcium, and H2O2 were measured using validated methods. In the cortex, hemispheres and cerebellum/medulla oblongata of the group treated with cerebrolysin and 3-NPA, the levels of DA and LP decreased. In addition, calcium and H2O2 levels decreased in the hemispheres of the same group, while GSH increased in cortex. The increased dopamine metabolism due to the administration of cerebrolysin led to increased formation of radical species and oxidative stress, especially when free radicals were generated by 3-NPA
Evaluación de control neuronal con arquitectura óptima para convertidor DC/DC
Martínez Sarmiento,Fredy Hernán; Castiblanco Ortíz,Mariela;
Ingeniería e Investigación , 2009,
Abstract: controlling dc/dc converters (topologies widely used in the active reduction of harmonic content for singlephase nonlinear low power equipment) raises great design challenges due to the mathematical model's complexity and its highly nonlinear dynamic characteristics. artificial intelligence techniques, such as neuronal networks, suppose great improvements in design and final performance, given their capacity for learning complex dynamics and generalising their behaviour. this work was aimed at proposing (and evaluating dynamic response later on) direct control link with neuronal networks which also allowed eliminating test elements and error in its design. artificial neuronal networkbased direct control was designed as well as possible using bioinspired search models. this simultaneously optimised two different but fundamental aspects of the network: architecture and the weight of the connections. the control was applied to a boost converter. the results led to observing the scheme's dynamic performance; response time and exit voltage delta led to concluding that the criteria selected for designing the control were appropriate and represented a contribution towards developing control applications of dc/dc switchmode systems.
Evaluación de control neuronal con arquitectura óptima para convertidor DC/DC Evaluating neural control with optimal architecture for DC/DC converter
Martínez Sarmiento Fredy Hernán,Castiblanco Ortíz Mariela
Ingeniería e Investigación , 2009,
Abstract: El control de convertidores DC/DC, topologías utilizadas ampliamente en la reducción activa de contenido armónico para equi- po monofásico no lineal de baja potencia, plantea grandes retos de dise o debido a lo complejo del modelo matemático y su característica dinámica altamente no lineal. Técnicas de inteligencia artificial como las redes neuronales, suponen grandes me- joras en el dise o y desempe o final, dada su capacidad de aprender dinámicas complejas y generalizar su comportamiento. La motivación de este trabajo fue la de plantear (y posteriormente evaluar la respuesta dinámica) un lazo de control directo con re- des neuronales, que permitiera adicionalmente eliminar elementos de prueba y error en su dise o. Se propone un control direc- to basado en red neuronal artificial, cuyo dise o se realizó de forma óptima utilizando modelos de búsqueda bioinspirada, esto para optimizar simultáneamente dos aspectos diferentes pero fundamentales de la red: la arquitectura y los pesos de las cone- xiones. El control es aplicado a un convertidor boost. Los resultados obtenidos permiten observar el desempe o dinámico del es- quema, para el cual los tiempos de respuesta y los delta de voltaje en la salida permiten concluir que los criterios seleccionados para el dise o del control son apropiados y representan un aporte en el desarrollo de aplicaciones de control de sistemas con- mutados DC/DC. Controlling DC/DC converters (topologies widely used in the active reduction of harmonic content for single-phase nonlinear low -power equipment) raises great design challenges due to the mathematical model’s complexity and its highly nonlinear dynamic characteristics. Artificial intelligence techniques, such as neuronal networks, suppose great improvements in design and final per- formance, given their capacity for learning complex dynamics and generalising their behaviour. This work was aimed at propo- sing (and evaluating dynamic response later on) direct control link with neuronal networks which also allowed eliminating test ele- ments and error in its design. Artificial neuronal network-based direct control was designed as well as possible using bio-inspired search models. This simultaneously optimised two different but fundamental aspects of the network: architecture and the weight of the connections. The control was applied to a boost converter. The results led to observing the scheme’s dynamic performan- ce; response time and exit voltage delta led to concluding that the criteria selected for designing the control were appropriate and represented a contribution to
Evaluating neural control with optimal architecture for DC/DC converter
Fredy Hernán Martínez Sarmiento,Mariela Castiblanco Ortíz
- , 2009,
Abstract: Controlling DC/DC converters (topologies widely used in the active reduction of harmonic content for single-phase nonlinear low -power equipment) raises great design challenges due to the mathematical model’s complexity and its highly nonlinear dynamic characteristics. Artificial intelligence techniques, such as neuronal networks, suppose great improvements in design and final per- formance, given their capacity for learning complex dynamics and generalising their behaviour. This work was aimed at propo- sing (and evaluating dynamic response later on) direct control link with neuronal networks which also allowed eliminating test ele- ments and error in its design. Artificial neuronal network-based direct control was designed as well as possible using bio-inspired search models. This simultaneously optimised two different but fundamental aspects of the network: architecture and the weight of the connections. The control was applied to a boost converter. The results led to observing the scheme’s dynamic performan- ce; response time and exit voltage delta led to concluding that the criteria selected for designing the control were appropriate and represented a contribution towards developing control applications of DC/DC switchmode systems
EVALUATION OF THE COMPOSITION AND ABUNDANCE OF RESIDUES OF THE TRAWLING ACTIVITY IN THE GULF OF VALENCIA (SPANISH MEDITERRANEAN SEA)
Francisco Ciri León,Vladimir Ortíz Mu？oz,Ricardo Alvarez León
Luna Azul , 2006,
Abstract: The general purpose of the research on solid wastes, mainly plastics, existing in the trawling seabed of the Gulf of Valencia, is to find their composition and abundance. For 21 days during the eight months of field work, 1043 km were sampled during the 160 hours of trawling. The areas sampled were designated by the preexisting trawling pattern. The classification was done manually and according to its composition six fundamental kinds of residues were established: plastics, metals, glasses, woods, textiles and others. Plastic containers were counted as units and weighted with the rest of the plastics. 697 different items were obtained: 33.4% plastics, 26,3% metals, 17% glasses, 12,3% woods, 9.4% textiles, 1.6% others and a total of 77.5 kg of plastics.
Trabeculectomía con 5-fluorouracilo transoperatorio
Alegre Nú？ez,Juan R; García álvarez,Hernán; Hernández Pe？a,Eduardo; Ortíz Bermúdez,Osmany;
Revista Cubana de Oftalmolog？-a , 2002,
Abstract: in a study of 70 eyes operated on of glaucoma that underwent conventional trabeculectomy with the use of transoperative 5-fluorouracil, those eyes at high risk for postoperative closure of the fistula were excluded and subjected to several postoperative controls during a year and a half. complications characteristic of filtering surgery without antimetabolites that improved with the usual treatment were observed. an adequate control of the intraocular pressure was achieved without reoperations or hypotensive drugs, which makes us think about encouraging future results with this type of surgery
Trabeculectomía con 5-fluorouracilo transoperatorio Trabeculectomy with transoperative 5-Fluorouracil
Juan R Alegre Nú？ez,Hernán García álvarez,Eduardo Hernández Pe？a,Osmany Ortíz Bermúdez
Revista Cubana de Oftalmolog？-a , 2002,
Abstract: En un estudio sobre 70 ojos operados de glaucoma, a los que se les realizó una trabeculectomía convencional con uso de 5-fluorouracilo transoperatorio, se excluyeron los ojos con alto riesgo de cierre posoperatorio de la fistula y se les realizaron varios controles posoperatorios hasta el 1 a o. Se observaron complicaciones propias de la cirugía filtrante sin antimetabolitos, que mejoraron con el tratamiento habitual, y se logró un control adecuado de la presión intraocular sin necesidad de reoperaciones o de medicación hipotensora, lo que hace pensar en resultados prometedores con este tipo de cirugía In a study of 70 eyes operated on of glaucoma that underwent conventional trabeculectomy with the use of transoperative 5-Fluorouracil, those eyes at high risk for postoperative closure of the fistula were excluded and subjected to several postoperative controls during a year and a half. Complications characteristic of filtering surgery without antimetabolites that improved with the usual treatment were observed. An adequate control of the intraocular pressure was achieved without reoperations or hypotensive drugs, which makes us think about encouraging future results with this type of surgery
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