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Search Results: 1 - 10 of 191207 matches for " Gómez Carmona "
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Efecto del desbalance en las cargas sobre la valoración de confiabilidad de un sistema de distribución de energía eléctrica
Gómez Carmona,Oscar; Zapata,Carlos J.;
Revista de Ingeniería , 2007,
Abstract: many three-phase distribution feeders are unbalanced because, first, they serve their customers by means of single-phase distribution transformers; second, they use components which operate in single-phase manner; third, most of the failures that affect their components are single-phase. this important fact must be included in reliability studies because, as shown in this paper, when the contrary is assumed pessimistic assessments of the reliability indices are obtained which could lead to erroneous investment decisions.
Solución al problema del despacho hidrotérmico mediante simulación de Monte Carlo y punto interior
Garcés Ruiz,Alejandro; Gómez Carmona,Oscar;
Revista Facultad de Ingeniería Universidad de Antioquia , 2008,
Abstract: hydrothermal dispatch establishes the suitable relation between hydraulic and thermal generation with optimal operative cost in a planning period, according to generation, transmission and load restrictions; moreover, it establishes the rational and efficient use of the energetic resources in the power electric systems. normally the hydrothermal dispatch problem has been simplified to find a solution with a reasonable computational time. the principal simplifications have been: to fit lineally the thermal functions cost, to eliminate the network restrictions, to dispatch in a unique node and to consider the load and reservoir flow in a deterministic way. this paper presents a methodology which solves the hydrothermal dispatch problem using interior point method and monte carlo simulation, the proposed model considers the thermal cost curves, the network restrictions and the stochastic forecasting of load and reservoirs flow, allowing to obtain probability distributions of the output variables (cost function, output power, etc).
Efecto del desbalance en las cargas sobre la valoración de confiabilidad de un sistema de distribución de energía eléctrica
Oscar Gómez Carmona,Fernando Jiménez Mantilla
Revista de Ingeniería , 2007,
Abstract: Muchos circuitos primarios de distribución trifásicos son desbalanceados porque, primero, atienden a sus usuarios por medio de transformadores de distribución monofásicos; segundo, utilizan componentes de operación monopolar; y, tercero, la mayoría de las fallas que afectan sus componentes son monofásicas. Este importante hecho debe incluirse en los estudios de confiabilidad pues, como se muestra en este artículo, cuando se asume lo contrario se obtienen valoraciones pesimistas de los índices de confiabilidad, lo que puede llevar a decisiones de inversión erróneas./ Many three-phase distribution feeders are unbalanced because, first, they serve their customers by means of single-phase distribution transformers; second, they use components which operate in single-phase manner; third, most of the failures that affect their components are single-phase. This important fact must be included in reliability studies because, as shown in this paper, when the contrary is assumed pessimistic assessments of the reliability indices are obtained which could lead to erroneous investment decisions.
INFERENCIA ESTADíSTICA UTILIZANDO REDES NEURONALES ARTIFICIALES
OSCAR GóMEZ CARMONA,LINA PAOLA GARCéS N.
Scientia Et Technica , 2004,
Abstract: Este artículo presenta una metodología para construir modelos probabilísticos de datos aleatorios continuos utilizando redes neuronales artificiales.
Cálculo del valor en riesgo (VAR) en el despacho hidrotérmico a mediano plazo
Alejandro Garcés Ruiz,Oscar Gómez Carmona
Scientia Et Technica , 2007,
Abstract: El análisis de riesgos es una metodología destinada a facilitar la toma de decisiones debido a la incertidumbre implícita en los problemas reales. Una herramienta altamente utilizada, es el Valor en Riesgo (VaR) el cual es un método de medición del riesgo usado especialmente en análisis de tipo financiero. En este artículo, este método será aplicado al problema del despacho hidrotérmico para determinar el costo mínimo de operación que se puede garantizar ante la incertidumbre en las afluencias y la demanda.
Monitorización con vídeo-EEG y ECG simultáneo para el diagnóstico diferencial de trastornos de conciencia transitorios: A propósito de un caso Video-EEG monitoring and simultaneous ECG for the differential diagnosis of transient consciousness disorders: A case report
M. Carmona-Iragui,A. Gómez-Ibá?ez,M. Carmona-Abellán,C. Gasca Salas
Anales del Sistema Sanitario de Navarra , 2012,
Abstract: Se presenta el caso de una mujer de 36 a os, con antecedentes de trastornos de conciencia transitorios con cortejo vegetativo en la adolescencia, interpretados como crisis epilépticas y tratados con ácido valproico durante dos a os. Tras permanecer nueve a os asintomática, reaparecieron asociados a migra a, vómitos y alguna convulsión generalizada. El electroencefalograma y la resonancia magnética cerebral resultaron normales e inició tratamiento con zonisamida, sin beneficio. Estudios cardiológicos posteriores objetivaron bloqueo de rama izquierda, que coincidía con mareo. Se completó el estudio mediante monitorización con vídeo-EEG, donde tuvo un episodio que evidenció actividad epileptiforme temporal derecha, estableciéndose el diagnóstico de epilepsia focal de causa desconocida. Actualmente, permanece asintomática con oxcarbacepina. La anamnesis es fundamental para diferenciar trastornos de conciencia transitorios, especialmente síncopes y crisis epilépticas, pero no siempre es suficiente. La monitorización con vídeo-EEG y registro simultáneo de electrocardiograma resulta muy útil para distinguirlos. We present the case of a 36 year-old woman, with history of transient consciousness disorders with vegetative state, interpreted as epileptic seizures and treated with valproic acid for two years. After nine asymptomatic years, they reappeared associated with migraine, vomiting and some generalized convulsions. Electroencephalogram and cerebral magnetic resonance turned out normal, and treatment with zonisamide was started, without beneficial results. Later cardiological studies objectified a blockage of the left branch that coincided with dizziness. The study was completed with Video-EEG monitoring, where there was an episode that showed right temporal epileptiform activity, with a diagnosis established of focal epilepsy of unknown etiology. At present, she remains asymptomatic with oxycarbazepine.
Widespread Secondary Contact and New Glacial Refugia in the Halophilic Rotifer Brachionus plicatilis in the Iberian Peninsula
Sergi Campillo,Manuel Serra,María José Carmona,Africa Gómez
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0020986
Abstract: Small aquatic organisms harbour deep phylogeographic patterns and highly structured populations even at local scales. These patterns indicate restricted gene flow, despite these organisms' high dispersal abilities, and have been explained by a combination of (1) strong founder effects due to rapidly growing populations and very large population sizes, and (2) the development of diapausing egg banks and local adaptation, resulting in low effective gene flow, what is known as the Monopolization hypothesis. In this study, we build up on our understanding of the mitochondrial phylogeography of the halophilic rotifer Brachionus plicatilis in the Iberian Peninsula by both increasing the number of sampled ponds in areas where secondary contact is likely and doubling sample sizes. We analyzed partial mitochondrial sequences of 252 individuals. We found two deep mitochondrial DNA lineages differing in both their genetic diversity and the complexity of their phylogeographic structure. Our analyses suggest that several events of secondary contact between clades occurred after their expansion from glacial refugia. We found a pattern of isolation-by-distance, which we interpret as being the result of historical colonization events. We propose the existence of at least one glacial refugium in the SE of the Iberian Peninsula. Our findings challenge predictions of the Monopolization hypothesis, since coexistence (i.e., secondary contact) of divergent lineages in some ponds in the Iberian Peninsula is common. Our results indicate that phylogeographic structures in small organisms can be very complex and that gene flow between diverse lineages after population establishment can indeed occur.
Survival of TNF antagonists in spondylarthritis is better than in rheumatoid arthritis. Data from the Spanish registry BIOBADASER
Loreto Carmona, Juan J Gómez-Reino, on behalf of the BIOBADASER Group
Arthritis Research & Therapy , 2006, DOI: 10.1186/ar1941
Abstract: The term spondylarthritis (SpA) refers to a group of conditions with inflammation at the entheses, axial skeleton, peripheral joints, and non-articular structures [1-3]. It includes ankylosing spondylitis (AS), reactive arthritis, undifferentiated SpA, juvenile spondylitis, and the arthritis associated with psoriasis or inflammatory bowel diseases. These conditions occur in approximately 1% of the general population [3]. Because of overlapping clinical features, diagnosis of any single one from among the several within the group is sometimes difficult. Nevertheless, treatment does not differ very much among the different conditions. Non-steroidal anti-inflammatory drugs (NSAIDs) have a role in symptom modification and disease control in patients with AS [4,5] as do methotrexate and sulfasalazine with psoriatic arthritis (PsA) and AS [6-17]. In both conditions, these drugs have demonstrated some benefit in peripheral arthritis. In axial disease, evidence is lacking.Recently, tumor necrosis factor (TNF) inhibitors have been found to be safe and effective in the short-term management of AS, PsA, enteropathic arthritis, and juvenile SpA in patients failing to respond to traditional therapies [17-34]. Unlike in rheumatoid arthritis (RA), however, their long-term efficacy and safety in such conditions are largely unknown.In February 2000, the Spanish Society of Rheumatology (SER) launched a drug registry (BIOBADASER) of patients with any rheumatic condition treated with biologic disease modifiers. In the past 5 years, more than 5,000 patients from 100 centres have been included in the registry and followed up with [35]. Although the emphasis of BIOBADASER is in drug safety, information on drug discontinuation for any cause is gathered as well. For prescription of any biological disease modifier in a context of universal health coverage in Spain, the physician commits himself to assess effectiveness and safety regularly and discontinue medication when appropriate to meet o
TECNOLOGíA LIMPIA APLICADA AL TRATAMIENTO Y APROVECHAMIENTO DE RESIDUOS DE AMALGAMA DENTAL
Ruiz Córdoba,Jairo; Carmona,Rosaura; Gómez,Gabriel Jaime; Mu?oz,José Alejandro;
Luna Azul , 2008,
Abstract: the world problem regarding the environmental pollution due to human activities where mercury is used increases the contamination generated by the dental amalgam scraps when they are inadequately disposed. although colombia has clear regulations regarding this issue, the problem subsists when oral health service institutions discard down the drainpipe, incinerate or bury the amalgam scraps that they produce as a disposal method. this occurs because the regulations are unknown or because, many times, they are partially or incorrectly applied. as a solution to this situation, the universidad de antioquia through the research groups: science and biomedical technology, precious materials and pyrometallurgical and material researches, and the dental supplies manufacturing and marketing company new stetic s.a., developed and implemented a eco-efficient recovery process for amalgam wastes in order to prevent any incorrect disposal that negatively impacts the environment, and to take advantage of the recovered metals by returning them to the production line. the process stages include the pyrometallurgical mercury recovery (at high temperatures) using a hermetical distiller called retorta, and the hydrometallurgical recovery (selective recovery in watery media) of the rest of the constituent metals. the latter permits the obtainment, in an eco-efficient and self-sustainable manner, of each metal which can be taken through a refining process to be reused.
ANáLISIS DE LIBERACIóN DE LOS GRUPOS DE MACERALES DEL CARBóN: CARBONES COLOMBIANOS
GóMEZ ROJAS,OLGA PATRICIA; CARMONA LóPEZ,INéS; BUSTAMANTE RúA,OSWALDO;
Boletín de Ciencias de la Tierra , 2007,
Abstract: three coal seams of different carboniferous zones from colombia were selected with the intention of evaluating the degree of liberation of the macerals groups. the method used in the studies mineral liberation of the hard rock was followed. the analyzed samples correspond to coals of the carboniferous zones of la guajira, antioquia, and boyacá, the analysis of liberation of the macerals was based on the results of the petrography analysis (determination of the percentage of free macerals and particles with mixed composition) of the samples with grain size mesh 230, 270, 325 and 400. during the pulverize the macerals groups in the coal present a tendency to the increase of free components. the liberation is not delimited at intervals of size, as usually happens in the minerals, the sizes oscillates between 5 and 350 microns for the liptinites and between 5 and 504 microns for the inertinites. the forms, sizes and associations (microlithotypes) that present the different groups from macerals, define the proportions of component free and mixed. the group maceral that presents greater probability of being frees is the vitrinite, because it is the maceral that is in greater proportion, this is demonstrated in the dominion of microlithotype vitrite in the different samples; the second group is the inertinite specially for the coals of boyacá and la guajira, the distribution of size and form of presentation of the macerals of the group of the inertinite (particle tissues) help their liberation. the liptinites by their association with the vitrinite and its low proportion in coals of boyacá and la guajira only present a significant degree of liberation in the sample of antioquia. in order to receive a greater rank of liberation of the components it is necessary to take inferior coals to grain size a to 10 microns.
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