Using the system dynamics paradigm in teaching and learning technological university subjets

2nd International Conference on Education and New Learning Technologies

DUAQUAL: calidad percibida por docentes y alumnos en la gestión universitaria

[ES] El proceso de Bolonia ha remarcado una perspectiva institucional en la preocupación por la gestión de la calidad del servicio prestado en las universidades y otras instituciones de enseñanza superior. La calidad del servicio en la educación superior no se centra exclusivamente en el proceso de enseñanza- aprendizaje y en la relación entre docente y discente, sino que debe estar también garantizada en el servicio prestado por las bibliotecas universitarias, los servicios de acción social, los servicios académicos y las secretarías departamentales.

Estrategias de lectura on-line en inglés como lengua extranjera

XXIV, 508 p.

Virtual Sensors for On-line Wheel Wear and Part Roughness Measurement in the Grinding Process

Grinding is an advanced machining process for the manufacturing of valuable complex and accurate parts for high added value sectors such as aerospace, wind generation, etc. Due to the extremely severe conditions inside grinding machines, critical process variables such as part surface finish or grinding wheel wear cannot be easily and cheaply measured on-line. In this paper a virtual sensor for on-line monitoring of those variables is presented. The sensor is based on the modelling ability of Artificial Neural Networks (ANNs) for stochastic and non-linear processes such as grinding; the selected architecture is the Layer-Recurrent neural network. The sensor makes use of the relation between the variables to be measured and power consumption in the wheel spindle, which can be easily measured. A sensor calibration methodology is presented, and the levels of error that can be expected are discussed. Validation of the new sensor is carried out by comparing the sensor's results with actual measurements carried out in an industrial grinding machine. Results show excellent estimation performance for both wheel wear and surface roughness. In the case of wheel wear, the absolute error is within the range of microns (average value 32 mu m). In the case of surface finish, the absolute error is well below R-a 1 mu m (average value 0.32 mu m). The present approach can be easily generalized to other grinding operations.