Diseño de un sistema de ordeño mecánico portátil

Los equipos mecánicos dedicados al agro en Colombia, son de gran importancia para la debida explotación de los recursos naturales casi ilimitados que este país presenta. El sector ganadero es una de las venas económicas de este país (teniendo hasta el 2008 más de cuatro millones de cabezas de ganado vacuno y produciendo en el 2008 más de 6 millones de litros de leche). De tal forma este sector genera miles de empleos y deja regalías significantes para los productores como para el gobierno (Fedegan@, 2008).76 p., + planos (7 p.)Contenido parcial: Definición del usuario final del producto -- Planteamiento de la situación de diseño -- Alcance y productos -- Determinación de la función principal o caja negra -- Determinación del diámetro interior mínimo de la conducción de leche

Trend analysis in two standard growth models

This paper analyzes the trend processes characterized by two standard growth models using simple econometrics. The first model is the basic neoclassical growth model that postulates a deterministic trend for output. The second model is the Uzawa-Lucas model that postulates a stochastic trend for output. The aim is to understand how the different trend processes for output assumed by these two standard growth models determine the ability of each model to explain the observed trend processes of other macroeconomic variables such as consumption and investment. The results show that the two models reproduce the output trend process. Moreover, the results show that the basic growth model captures properly the consumption trend process, but fails in characterizing the investment trend process. The reverse is true for the Uzawa-Lucas model.Uzawa-Lucas model, basic neoclassical growth model, trend process, cointegration

Cyclical Features of Uzawa-Lucas Endogenous Growth Model

This paper analyzes the cyclical properties of a generalized version of Uzawa-Lucas endogenous growth model. We study the dynamic features of different cyclical components of this model characterized by a variety of decomposition methods. The decomposition methods considered can be classified in two groups. On the one hand, we consider three statistical filters: the Hodrick-Prescott filter, the Baxter-King filter and Gonzalo-Granger decomposition. On the other hand, we use four model-based decomposition methods. The latter decomposition procedures share the property that the cyclical components obtained by these methods preserve the log-linear approximation of the Euler-equation restrictions imposed by the agent’s intertemporal optimization problem. The paper shows that both model dynamics and model performance substantially vary across decomposition methods. A parallel exercise is carried out with a standard real business cycle model. The results should help researchers to better understand the performance of Uzawa-Lucas model in relation to standard business cycle models under alternative definitions of the business cycle.endogenous growth, decomposition methods, cyclical features

Pos-simulacro e hipermodernidad en \u3cem\u3eComo la sombra que se va\u3c/em\u3e, de Antonio Muñoz Molina

Demostraré que Antonio Muñoz Molina, en su novela Como la sombra que se va (2014) supera el paradigma posmoderno de simulacro. La novela entrecruza geográficamente Lisboa tres relatos: una crónica de la escapada de James Earl Ray después de asesinar al reverendo Martin Luther King y las memorias de la creación tanto de su novela El invierno en Lisboa (1987) como de Como la sombra que se va. Muñoz Molina proyecta la crónica de Ray y la memoria de la creación de El invierno en Lisboa no sobre una Lisboa hiperreal, sino sobre un espacio concreto en el que se reconstruye una narración de un orden que podemos llamar de pos-­simulacro

Trend analysis in two standard growth models

This paper analyzes the trend processes characterized by two standard growth models using simple econometrics. The first model is the basic neoclassical growth model that postulates a deterministic trend for output. The second model is the Uzawa-Lucas model that postulates a stochastic trend for output. The aim is to understand how the different trend processes for output assumed by these two standard growth models determine the ability of each model to explain the observed trend processes of other macroeconomic variables such as consumption and investment. The results show that the two models reproduce the output trend process. Moreover, the results show that the basic growth model captures properly the consumption trend process, but fails in characterizing the investment trend process. The reverse is true for the Uzawa-Lucas model.Financial support from Ministerio de Ciencia y Tecnología, Gobierno Vasco and Universidad del País Vasco (Spain) through projects BEC2000-1393, PI-1999-131 and 9/UPV00035.321-13511/2001, respectively, is gratefully acknowledged

Teoría de precios de arbitraje. Evidencia empírica para Colombia a través de redes neuronales

RESUMENEsta investigación utiliza una red neuronal multicapa para relacionar el Índice General de Bolsa de Valores de Colombia (IGBC) con fundamentales macroeconómicos y variables Financieras. Proponemos dos modelos: un modelo APT (fundamentales macroeconómicos) y un modelo APT modificado (fundamentales macroeconómicos + indicador de las bolsas del mundo); de acuerdo a nuestro análisis el APT tradicional se ajusta mejor para predecir el mercado de valores Colombiano. Los resultados confirman que las redes neuronales artificiales (ANN) son más efectivas que los modelos estadísticos tradicionales por su capacidad explicativa y precisión.ABSTRACTThis research uses a multilayer neural network to relate the General Index from Colombia Stock Exchange (IGBC) with macroeconomic fundamentals and fiancial variables. We propose two models: an APT (macroeconomic fundamentals) one and a modified APT (macroeconomic fundamentals + international stock markets indicator); according to our analysis the traditional APT predicts more accurately the behavior of the Colombian stock market. The results confirm that the artificial neural network (ANN) approach is more effective than traditional statistical models given its explanatory power and precision.Teoría de precios de arbitraje, variables macroeconómicas,mercado de valores, redes neuronales artificiales.