Search results for "Process"
showing 10 items of 22310 documents
Valoración de los Proyectos de Grado sobre Educación Ambiental en la Universidad, Aplicando la Hipótesis de Progresión
2015
Este trabajo aplica la hipótesis de progresión como metodología para la valoración de los proyectos de grado de los estudiantes en Educación Ambiental en la Universidad.Se han analizado, los proyectos realizados por los alumnos de la licenciatura en Biología y Educación Ambiental, en la Universidad del Quindío, Colombia. Cuyo objetivo tiene la formación de profesores para los diferentes niveles educativos. La hipótesis de progresión permite valorar el cambio conceptual presentado en los proyectos de grado no como un proceso puntual sino como un proceso de evolución de los contenidos.La investigación muestra que los Proyectos fin de grado de los estudiantes de Biología y educación A…
Corrigendum to "Experimental study of the role of physicochemical surface processing on the IN ability of mineral dust particles" published in Atmos.…
2011
Atmospheric Chemistry and Physics, 11 (22)
A2Ba: Adaptive Background Modelling for Visual Aerial Surveillance Conditions
2015
International audience; Background modelling algorithms are widely used to define a part of an image that most time remains stationary in a video. In surveillance tasks, this model helps to recognize those outlier objects in an area under monitoring. Set up a background model on mobile platforms (UAVs, intelligent cars, etc.) is a challenging task due camera motion when images are acquired. In this paper, we propose A2Ba, a robust method to support instabilities caused by aerial images fusing different information about image motion. We used frame difference as first approximation, then age of pixels is estimated. This latter gives us an invariability level of a pixel over time. Gradient di…
kLa MEASUREMENT IN BIOREACTORS
2010
For accurately measuring kLa in bioreactors the dynamic pressure method (DPM) was introduced by Linek et al. (1993). In this work a simplified version of the same method is discussed. With respect to the original DPM, the simplified version greatly simplifies data treatment. In fact final constant slope observable in the usual semi-log diagram of residual driving force versus time may be simply corrected to obtain the real kLa value with negligible inaccuracy. Experimental data obtained on a lab-size stirred tank reactor confirm all model predictions, including the feature that the adoption of large pressure changes may lead to a better accuracy.
Green Synthesis of Vanillin: Pervaporation and Dialysis for Process Intensification in a Membrane Reactor.
2019
In the present work, two different membrane processes (pervaporation and dialysis) are compared in view of their utilization in a membrane reactor, where vanillin, which is probably the most important aroma of the food industry, is synthesized in a green and sustainable way. The utilized precursor (ferulic acid, which is possibly a natural product from agricultural wastes) is partially oxidized (photocatalytically or biologically) and the product is continuously recovered from the reacting solution by the membrane process to avoid its degradation. It is observed that pervaporation is much more selective towards vanillin than dialysis, but the permeate flux of dialysis is much higher. Furthe…
Fabrication and characterization of Metal and Metal Oxide Nanostructures Grown by metal displacement deposition into anodic alumina membranes
2011
Abstract preview not available - see full-text PDF article.
Vortex shape in unbaffled stirred vessels: experimental study via digital image analysis
2011
There is a growing interest in using unbaffled stirred tanks for addressing certain processing needs. In this work, digital image analysis coupled with a suitable shadowgraphy-based technique is used to investigate the shape of the free-surface vortex that forms in uncovered unbaffled stirred tanks. The technique is based on back-lighting the vessel and suitably averaging vortex shape over time. Impeller clearance from vessel bottom and tank filling level are varied to investigate their influence on vortex shape. A correlation is finally proposed to fully describe vortex shape also when the vortex encompasses the impeller.
EXPERIMENTAL INVESTIGATION OF DILUTE SOLID-LIQUID SUSPENSION IN AN UNBAFFLED STIRRED VESSELS BY A NOVEL PULSED LASER BASED IMAGE ANALYSIS TECHNIQUE
2009
The availability of experimental information on solid distribution inside stirred tanks is a topic of great importance in several industrial applications. The measurement of solid particle distribution in turbulent multiphase flow is not simple and the development of suitable measurement techniques is still in progress. In this work a novel non-intrusive technique for measuring particle concentration fields in solid-liquid systems is employed. The technique makes use of a laser sheet, a high sensitivity digital camera for image acquisition and a Matlab procedure for post-processing the acquired images. Experimental data are here obtained for the case of an unbaffled stirred tank. Stable tor…
Morphodynamics of river bed variation with variable bedload step length
2013
Abstract. Here we consider the 1-D morphodynamics of an erodible bed subject to bedload transport. Fluvial bed elevation variation is typically modeled by the Exner equation, which, in its classical form, expresses mass conservation in terms of the divergence of the bedload sediment flux. An entrainment form of the Exner equation can be written as an alternative description of the same bedload processes, by introducing the notions of an entrainment rate into bedload and of a particle step length, and assuming a certain probability distribution for the step length. This entrainment form implies some degree of nonlocality, which is absent from the standard flux form, so that these two express…
Prácticas artísticas de visualización entre cuerpo y objeto en entornos de mediación pedagógica
2019
El artículo es producto de un proceso de investigación basado en la metodología de la Photo Based Research realizada con alumnado universitario en formación como futuros docentes. Parte del análisis de prácticas artísticas performativas del cuerpo, en relación con un entorno de mediación pedagógica y los objetos que lo configuran, para establecer una nueva mirada analítica sobre el papel de mediación del entorno y sus objetos sobre la posición del docente y su identidad. Ello nos permite vislumbrar y poder subvertir, utilizando la propuesta de análisis de visualización de entornos mediáticos, que desarrollamos en el artículo, estos efectos de mediación. Con ello, podemos articular, por medi…