Determinación experimental de la permitividad como función de la frecuencia

Objective: To determine the behavior of dielectric permittivity of class II ceramic capacitor in function of frequency up to 10MHz. Context:  in telecommunications and high frequency circuits is necessary to take into account the diminishing of permittivity on dielectrics of ceramic capacitors with the frequency growth, two quantitative methods are proposed to determine this behavior. Method: First, the impedance meter bridge FLUKE PM5306 was used in the frequency range from 10^2 Hz to 10^5 Hz; and second, a novel low-cost electronic circuit for the frequency range between 10^4 Hz to 10^7. Results:  The results from the circuit were validated using the impedance meter bridge RLC FLUKE PM 6306. The measure of the complex capacitance from three capacitors and their loss tangent were obtained. Conclusions: The capacitance decreasing with the increment of the frequency was observed in the impedance meter bridge and the implemented circuit, finding a convergence between both methods in the common frequency region.Contexto: En telecomunicaciones y los circuitos en alta frecuencia es necesario tener en cuenta la disminución de la permitividad de los dieléctricos en capacitores cerámicos con el aumento de la frecuencia, se proponen 2 métodos cuantitativos para determinar el comportamiento. Método: Primero se utilizó el puente medidor de impedancias FLUKE PM6306 en el rango de frecuencias entre  Hz hasta  Hz, y segundo, un circuito electrónico novedoso de bajo costo para frecuencias entre  Hz hasta  Hz. Resultados: Se validaron los resultados obtenidos con el circuito contrastándolo con el puente de impedancias RLC FLUKE PM6306. Se obtuvo la medición de la capacitancia compleja de tres diferentes condensadores, así como la tangente de pérdidas asociada. Conclusiones: Se observó la disminución de la capacitancia con el aumento de la frecuencia a través del puente de impedancias, así como con el circuito implementado, encontrando convergencia entre los dos métodos en la región común de frecuencia

In-Situ Real Time Monitoring and Control of Mold Making and Filling Processes: Final Report

This project presents a model for addressing several objectives envisioned by the metal casting industries through the integration of research and educational components. It provides an innovative approach to introduce technologies for real time characterization of sand molds, lost foam patterns and monitoring of the mold filling process. The technology developed will enable better control over the casting process. It is expected to reduce scrap and variance in the casting quality. A strong educational component is integrated into the research plan to utilize increased awareness of the industry professional, the potential benefits of the developed technology, and the potential benefits of cross cutting technologies