Transformada de Laplace y sus aplicaciones en sistemas dinámicos: una revisión

This paper presents a review of Laplace Transform (LT) applications in the analysis of linear dynamic systems. Is presented the importance of the transforms; the definition of the Transform; theorems and properties with applications and finally, the use of LT for the calculation of: steady state error, transfer functions, ordinary differential equations solution, frequency responses, signal analysis and block diagrams. The modeling and operational analysis with LT of a multipurpose reactor is proposed as a didactic situation for academic purposes.Este artículo presenta una revisión sobre las aplicaciones de la transformada de Laplace (TL) en el análisis de sistemas dinámicos lineales. Se presenta la importancia de la transformada; la definición de la transformada; los teoremas y propiedades con aplicaciones y por último, aplicaciones del uso de la TL para el cálculo de: error de estado estacionario, funciones de transferencia, solución de ecuaciones diferenciales ordinarias, respuestas en frecuencia, análisis de señales y diagramas de bloques. Se propone, como situación didáctica para propósitos académicos, el modelamiento y análisis operacional con TL de un reactor multipropósito

La necesidad de peaje por congestión en Medellín : una perspectiva económica

RESUMEN: Se presenta una breve descripción de la congestión vehicular en Medellín, y la necesidad de implementar el sistema de peaje por congestión (PC) desde una óptica económica. Se describe la restricción a la circulación vehicular del “Pico y Placa,” mostrando que la medida es paliativa y que es necesaria la implementación del PC. Se realiza un análisis costo-beneficio para valorar los efectos de implementar una estrategia en forma hipotética de PC basado en datos de investigaciones. La mejor solución debida al PC es presentada y considerada como lo óptimo para lograr encontrar la tasa de congestión que maximiza el bienestar social. El principal hallazgo es que el beneficio neto de la implementación es positivo. Por lo tanto, se recomienda la implementación del PC para mejorar la eficiencia en el uso de la infraestructura vial en la ciudad basado en principios económicos. Finalmente, se presentan algunas recomendaciones para mejorar la movilidad en la ciudad.ABSTARCT: This paper presents a brief description of vehicular congestion in Medellin, Colombia, and discusses the need to implement congestion pricing (CP) from an economic point of view. It describes the license plate-based traffic restriction (Pico y Placa) in the city, showing that the measure is palliative, and that the implementation of CP is necessary. A cost-benefit analysis is presented to assess the effects of implementing a hypothetical CP strategy based on data from previous studies. The first-best solution for CP is presented, and considered as the optimal policy for deciding on the congestion rate that would maximize social welfare. The main finding is that the net benefit of implementation costs is positive. Therefore, the implementation of a CP strategy is recommended to improve the efficiency of road infrastructure use in the city based on economic principles. Finally, a set of recommendations for improving the city’s mobility in the future are presented

Plan de viabilidad de una boutique Gucci en Tenerife

El propósito de nuestro Trabajo de Fin de Grado es realizar un plan de viabilidad, que tiene por objeto abrir una boutique Gucci en Tenerife. Ubicada en la zona sur de la isla, Adeje. Pretendemos satisfacer la demanda de productos de moda y lujo de la clientela local, además de la importante masa turística que visita la isla. Este proyecto se estructura de la siguiente forma: Una introducción, explicación de la historia de la marca Gucci, una visión del panorama actual, un análisis del entorno y de la empresa, la ejecución del plan de marketing, el plan de recursos humanos y el plan económico-financiero, estudio del régimen jurídico y de la ubicación del local y finalmente, la conclusión del proyecto.The main objective of our End Grade Project is the creation of a viability plan, which purpose is open a Gucci store in Tenerife. Located on the southern part of the island, in Adeje, we pretend to satisfy not only for locals, furthermore, the huge turistic people that visits the island luxury and fashion demand. This project´s structure is formed by: An explanation, Gucci´s history, a current view, an environment and own business analysis, creation of marketing, employees, economic and financial plans, legal regime and store location and finally, the conclusion

El riesgo financiero en las empresas españolas en el año 2014

El estudio valora el riesgo financiero mediante un modelo probabilístico en las empresas de España, que durante el año 2014 reportaron información financiera ante la Comisión Nacional del Mercado de Valores (CNMV). Se realizó una depuración y análisis de los estados financieros de las empresas, para luego proceder a determinar riesgos financieros de liquidez, endeudamiento y recuperación de cartera mediante los cálculos de los indicadores correspondientes y con ellos, determinar el riesgo financiero de cada empresa y por sector. Posteriormente, se validó el modelo aplicando un modelo Logit que permitió establecer la bondad, consistencia y confiabilidad del modelo. Entre los principales hallazgos fueron que el 43% de las empresas objetivo de estudio presentaron riesgo financiero, frente a un 57% que no presentaron riesgo financiero, los sectores que más presentaron riesgo fueron los sectores de servicios y energético. De los tres indicadores usados en el modelo, los de mayor riesgo fueron la liquidez y el endeudamiento con el 69% y 5 respectivamente. Las pruebas estadísticas, permitieron aceptar la hipótesis de trabajo que expresa que la liquidez, el endeudamiento y la cartera influyen negativamente sobre el riesgo financiero de las empresas

Intoxicación escombroide secundaria al consumo de atún: presentación de un caso

Scombroid poisoning is caused by the consumption of certain types of fish (from the Scombridae family), especially tuna. Due to inadequate refrigeration procedures, these fish have high levels of histamine which generate symptoms similar to those of a food allergy in their consumers, so it is frequently underdiagnosed. It is self-limited in a few hours and the symptoms are usually not serious, except for specific cases reported in the literature of hypotension, bronchospasm, respiratory distress, tachyarrhythmias, and even acute myocardial infarction.We report here the case of a woman admitted to the emergency department of a third level hospital in Medellín a few minutes after eating tuna with the typical symptoms of intoxication, as well as tachyarrhythmias, a serious and atypical manifestation.La intoxicación escombroide es ocasionada por el consumo de ciertos tipos de pescado (de la familia Scombridae), comúnmente el atún, los cuales acumulan grandes concentraciones de histamina cuando los procedimientos de refrigeración son inadecuados, ocasionando en quienes los consumen síntomas muy similares a los de una alergia alimentaria, por lo que es frecuente que no se diagnostique correctamente. Generalmente, los síntomas desaparecen en pocas horas y no suelen ser graves, excepto algunos casos descritos en la literatura especializada, de hipotensión, broncoespasmo, dificultad respiratoria, taquicardia supraventricular e, incluso, infarto agudo de miocardio.Este fue, precisamente, el caso de una mujer que ingresó al servicio de urgencias de un hospital de tercer nivel de Medellín a los pocos minutos de haber ingerido atún con una sintomatología típica de la intoxicación, pero con taquicardia supraventricular, una de sus manifestaciones graves y atípicas

Proyecto de modernización de la formación profesional

Documento liderado por la Subdirección de Formación Profesional y Desarrollo Social en el cual participaron siete regionales del SENA y un grupo inter divisiones de la Dirección General. En el documento se establece el marco conceptual de la formación profesional como fundamento de la unidad técnica dentro del proceso de modernización SENADocument led by the Subdirectorate of Vocational Training and Social Development in which seven regional SENA and an inter-division group of the General Directorate participated. The document establishes the conceptual framework of vocational training as the foundation of the technical unit within the process of modernization SENANuevos ámbitos para la formación profesional -- Una concepción moderna de la formación profesional -- Principios de la formación profesional -- Enfoque pedagógico de la formación profesional -- Caracterización de la formación profesional -- Misión Institucionaln

Human papilloma virus genotypes in dysplasia and epithelial hyperplasia of oral cavity using the luminex xmap technology. A multicenter study

Oral cancer associated with high risk (HPV-HR) human papilloma virus (HPV) has been increasing. HPV-HR has been associated with epithelial dysplasia, however, little information exists on its frequency in epithelial hyperplasia lesions. The aim of this study is to compare HPV genotypes in dysplastic and hyperplastic lesions of oral cavity. Two hundred and fifty oral lesions: 131 dysplasia and 119 hyperplasia from two regions of Colombia were evaluated. One hundred seventy-four coming from urban area and 104 from a high risk population to oral cancer from a rural area. HPV was identified by qPCR and Twenty-four HPVs genotypes were evaluated by Luminex® technology. Logistic regressions were performed to establish the associations between HPV infections with oral dysplasia. Twenty-eight percent (70/250) of the samples were positives for any HPV and HPV-HRs were more frequently than low risk HPVs. HPV-16 was the most detected genotype (16%) followed by HPV-31, 53, 18 and 45. HPV, HPV-HRs and HPV-16 were only associated with dysplasia in urban area; OR 3.28 (CI 95% 1.49-7.17), OR 7.94 (CI 95% 2.97-21.2) and OR 5.90 (CI 95% 2.05-17). Individuals in rural area showed more HPV and HPV-HRs infection in hyperplasic lesions than urban population. The majority of HPV+ lesions had multi-type of HPV (52/70) and the urban individuals showed more genotypes than rural population. HPV-.HRs are frequently found in hyperplastic and dysplastic epithelial lesions. HPV-HRs and HPV-16 were associated with dysplasia in urban population. Rural high risk population and urban population differ in the frequency and variety of HPV genotypes

The O3N2 and N2 abundance indicators revisited: improved calibrations based on CALIFA and T e-based literature data

Astronomy and Astrophysics 559 (2013): A114 reproduced with permission from Astronomy and AstrophysicsThe use of integral field spectroscopy is since recently allowing to measure the emission line fluxes of an increasingly large number of star-forming galaxies, both locally and at high redshift. Many studies have used these fluxes to derive the gas-phase metallicity of the galaxies by applying the so-called strong-line methods. However, the metallicity indicators that these datasets use were empirically calibrated using few direct abundance data points (Te-based measurements). Furthermore, a precise determination of the prediction intervals of these indicators is commonly lacking in these calibrations. Such limitations might lead to systematic errors in determining the gas-phase metallicity, especially at high redshift, which might have a strong impact on our understanding of the chemical evolution of the Universe. The main goal of this study is to review the most widely used empirical oxygen calibrations, O3N2 and N2, by using newdirect abundance measurements. We pay special attention to (1) the expected uncertainty of these calibrations as a function of the index value or abundance derived and (2) the presence of possible systematic offsets. This is possible thanks to the analysis of the most ambitious compilation of Te-based H ii regions to date. This new dataset compiles the Te-based abundances of 603 H ii regions extracted from the literature but also includes new measurements from the CALIFA survey. Besides providing new and improved empirical calibrations for the gas abundance, we also present a comparison between our revisited calibrations with a total of 3423 additional CALIFA H ii complexes with abundances derived using the ONS calibration from the literature. The combined analysis of T e-based and ONS abundances allows us to derive their most accurate calibration to date for both the O3N2 and N2 single-ratio indicators, in terms of all statistical significance, quality, and coverage of the parameters space. In particular, we infer that these indicators show shallower abundance dependencies and statistically significant offsets compared to others'. The O3N2 and N2 indicators can be empirically applied to derive oxygen abundances calibrations from either direct abundance determinations with random errors of 0.18 and 0.16, respectively, or from indirect ones (but based on a large amount of data), reaching an average precision of 0.08 and 0.09 dex (random) and 0.02 and 0.08 dex (systematic; compared to the direct estimations), respectivelyR.A. Marino is funded by the Spanish program of International Campus of Excellence Moncloa (CEI). D. Mast thank the Plan Nacional de Investigación y Desarrollo funding programs, AYA2012-31935 of the Spanish Ministerio de Economía y Competitividad, for the support given to this project. S.F.S thanks the the Ramón y Cajal project RyC-2011-07590 of the spanish Ministerio de Economía y Competitividad, for the support giving to this project. F.F.R.O. acknowledges the Mexican National Council for Science and Technology (CONACYT) for financial support under the program Estancias Postdoctorales y Sabáticas al Extranjero para la Consolidación de Grupos de Investigación, 2010-2012. We acknowledge financial support for the ESTALLIDOS collaboration by the Spanish Ministerio de Ciencia e Innovación under grant AYA2010- 21887-C04-03. BG-L also acknowledges support from the Spanish Ministerio de Economía y Competitividad (MINECO) under grant AYA2012- 39408-C02-02. J.F.-B. acknowledges financial support from the Ramón y Cajal Program and grant AYA2010-21322-C03-02 from the Spanish Ministry of Economy and Competitiveness (MINECO), as well as to the DAGAL network from the People’s Program (Marie Curie Actions) of the European Union’s Seventh Framework Program FP7/2007-2013/ under REA grant agreement number PITN-GA-2011-289313. CK has been funded by project AYA2010-21887 from the Spanish PNAYA. P.P. acknowledges support by the Fundação para a Ciência e a Tecnologia (FCT) under project FCOMP-01-0124-FEDER-029170 (Reference FCT PTDC/FIS-AST/3214/2012), funded by FCT-MEC (PIDDAC) and FEDER (COMPETE). R.M.G.D. and R.G.B. also acknowledge support from the Spanish Ministerio de Economía y Competitividad (MINECO) under grant AyA2010-15081. V.S., L.G., and A.M.M. acknowledge financial support from the Fundação para a Ciência e a Tecnologia (FCT) under program Ciência 2008 and the research grant PTDC/CTE-AST/112582/200

Temas Socio-Jurídicos. Volumen 17 No. 36 Junio 1999

La revista Temas Socio-jurídicos, en su edición número 36 que corresponde al año 17, entrega a sus lectores el producto del trabajo realizado por profesores y estudiantes de la Facultad de Derecho en el primer semestre de 1999.The magazine Temas Socio-jurídicos, in its 36th edition that corresponds to the year 17, delivers to its readers the product of the work carried out by professors and students of the Faculty of Law in the first semester of 1999