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There are many equipments that work the most part of their time in transient regime; therefore, in the design of their drive systems must be employed different methodologies to when, they work in stationary regime. In this paper is shown the application of two distinct methods to the design and selection of the components of an drive system for rapid movements. The Transient Power - Double Kinetic Energy Method and Torque - Time Constant Method were applied to select the drive system of a axis to linear guidance in a punch machine, this case was developed within a project founded by Colciencias. It was necessary to use MATLAB and information obtained from catalogs in order to carry out the required simulations in the evaluation process of the convenience of distinct drive kinds. Also, in this paper is analyzed the complementariness of the referenced methods. [ABSTRACT FROM AUTHOR]

In this paper, we present a methodology for calculating the thermal efficiency of a pot on an electric stove using numerical simulations in ANSYS FLUENT®. The system domain was divided into three subsystems: electrical resistors, the air volume inside the resistors, and the pot. It was determined that the heat transfer to the pot was mainly caused by conduction between the heating element and the pot surface, representing 85.7% of the total energy going into the system. Heat transfer by convection and radiation represented 13% and 1.3% of the total incoming energy, respectively. A method to set the initial value of the contact resistance between the electrical resistance and the pot based on experimental tests is also presented. This initial contact resistance value is a key parameter for the correct simulation of the system. The numerical simulations and experimental tests corresponded well with one another, with a difference of no more than 15% for all geometries analyzed. Finally, a substantial stove improvement is proposed. The enhancement consists of the suppression of the circulating currents that are formed inside the stove by adding an insulating material. With this improvement, the heat losses to the surroundings were reduced from 15.19% to 6.64%. And therefore, a potential reduction of the cost of living is possible in the main urban centers of Colombia. [ABSTRACT FROM AUTHOR]

This paper proposes a numerical method for the calibration of dynamic stochastic general equilibrium (DSGE) models. The method consists in the use of a hybrid algorithm, first to find the steady state, and then to minimize an objective function defined by the researcher according to the purposes of the calibration. The proposed method consists in the use of the Simulated Annealing algorithm followed by traditional optimization routines. The virtues of the algorithm are analyzed through Monte Carlo simulations, using a closed-economy model that has a steady state with no analytical solution. The results obtained in this exercise show that the proposed algorithm generates more precise results using less computational resources than traditional alternatives. Finally we present the calibration of a model for the Colombian economy, consisting of 179 equations and adjusted through 50 parameters to replicate 50 ratios. The maximum percent deviation of the steady-state ratios of the model with respect to the corresponding values in the Colombian economy is 7.9%, and in 29 of all the 50 cases this deviation is less than or equal to 1%. [ABSTRACT FROM AUTHOR]