Improving the surface finish of concave and convex surfaces using a ball burnishing process

The ball burnishing process is done to improve the surface finish of workpieces that have been previously machined. In this article we present the results of tests performed with this process that was applied to workpieces with a convex or concave surface of two different materials: aluminum A92017 and steel G10380. An experiment to do the tests was designed. The results of measurements of surface roughness are presented in this paper as well. These results are compared to those measured in the workpieces before being burnished. After that conclusions are drawn about the improvement of surface roughness applied to the workpieces through the ball burnishing process. The main innovation of this paper is that we work with concave and convex geometries. We also obtain a table of recomended parameter values for the process

MVBatch: A matlab toolbox for batch process modeling and monitoring

[EN] A novel user-friendly graphical interface for process understanding, monitoring and troubleshooting has been developed as a freely available MATLAB toolbox, called the MultiVariate Batch (MVBatch) Toolbox. The main contribution of this software package is the integration of recent developments in Principal Component Analysis (PCA) based Batch Multivariate Statistical Process Monitoring (BMSPM) that overcome modeling problems such as missing data, different speed of process evolution and length of batch trajectories, and multiple stages. An interactive user interface is provided, which aims to guide users in handling batch data through the main BMSPM steps: data alignment, data modeling, and the development of monitoring schemes. In addition, a small-scale non-linear dynamic simulator of the fermentation process of the Saccharomyces cerevisiae cultivation is available to generate realistic batch data under normal and abnormal operating conditions. This generator of synthetic data can be used for teaching purposes or as a benchmark to illustrate and compare the performance of new methods with sound techniques published in the field of BMSPM.This work is partially supported by the Spanish Ministry of Economy and Competitiveness and FEDER funds through the projects DPI2017-82896-C2-1-R and TIN2017-83494-R. Authors also acknowledge the volunteers to test MVBatch and report their impressions for this software tutorial.González Martínez, JM.; Camacho Paez, J.; Ferrer, A. (2018). MVBatch: A matlab toolbox for batch process modeling and monitoring. Chemometrics and Intelligent Laboratory Systems. 183:122-133. https://doi.org/10.1016/j.chemolab.2018.11.001S12213318

Design based inference using split questionnaire designs

ilustraciones, tablasAl usar una estrategia de muestreo (combinación de diseño y estimador) cualesquiera, se asume implícitamente en la literatura la regla de recoger todas las variables en todos los respondientes. En la actualidad las encuestas tienden a tener menores tasas de respuestas, en ocasiones debido a la longitud de los cuestionarios; se demanda una mayor cantidad de información a ser recolectada; se cuenta con la disponibilidad de fuentes secundarias más baratas como registros administrativos o big data que actúan como sustitutos de los datos de encuestas. Por lo tanto, es necesario buscar análisis que combinen eficiencia y flexibilidad como la técnica de diseños de cuestionarios divididos que reemplaza el supuesto de recoger todas las variables para todos los respondientes por recoger un subconjunto de la información requerida para cada unidad en la muestra. Sin embargo, bajo este tipo de estrategias estimadores de tipo Horvitz–Thompson o Hansen–Hurwitz para el total poblacional no han sido descritos para diseños muestrales complejos (probabilidades desiguales, estratificados, conglomerados y varias etapas). Con este trabajo se pretende incorporar la metodología de diseños de cuestionario dividido a los diseños de muestreo más conocidos y así, determinar la forma del estimador del total poblacional y su estimador de varianza. (Texto tomado de la fuente)By using a sampling strategy (combination of design and estimator), possibly the rule of collecting all variables in all respondents is duly assumed in the literature. Currently, surveys tend to have lower response rates, sometimes due to the length of the questionnaires; a greater amount of information is demanded to be collected; cheaper secondary sources such as administrative records or big data are available to act as surrogates for survey data. Therefore, it is necessary to look for analyzes that combine efficiency and flexibility, such as the technique of replaceable designs of divided questionnaires, which assumes the collection of all the variables for all the respondents by collecting a subset of the information required for each unit in the sample. However, under this type of strategy, Horvitz-Thompson or Hansen-Hurwitz type estimators for the total population have not been described for complex sample designs (unequal probabilities, stratified, conglomerates and various stages). The aim of this work is to incorporate the split questionnaire design methodology into the best-known test designs and thus determine the shape of the total population estimator and its variance estimator.MaestríaMagíster en Ciencias - Estadístic

Propuesta de un diseño de estación de monitorización en tiempo real: implementación y rendimiento en diferentes condiciones ambientales

With the aim of creating a real-time monitoring network for both oceanographic and meteorological data, a monitoring station conceptual design was developed. A common framework for software and electronics was adapted to different environmental conditions using two buoy approaches: one intended for oceanic waters, to be moored up to 30-40 m depth, where waves are the critical design factor, and one for continental waters (rivers, lakes and the inner part of estuaries), where currents are the critical design factor. When structures such as bridges are present in the area, the monitoring station can be installed on these structures, thus reducing its impact and increasing safety. In this paper, the design, implementation, operation and performance of these stations are described. A reliability index is calculated for the longest time series of the three related deployment options on the Galician coast: Cíes (oceanic buoy in front of the Ría de Vigo), Catoira (continental buoy in the Ulla river) and Cortegada (installation in a bed in the Ría de Arousa).Con el fin de crear una red de monitorización en tiempo real de variables tanto oceanográficas como meteorológicas, se ha desarrollado el diseño conceptual de una estación de monitorización. Este diseño común de electrónica y programación se ha adaptado a las diferentes condiciones ambientales del medio empleando dos tipos diferentes de boya: uno para aguas oceánicas, que puede ser fondeado hasta 30-40 m de profundidad, donde el oleaje es el factor crítico a tener en cuenta para su diseño, y otro para aguas continentales (ríos, lagos o incluso para la parte interior de estuarios), donde las corrientes son el principal elemento ambiental que ha de ser considerado. Asimismo, cuando existen estructuras en el medio, como puentes, esta estación puede ser instalada sobre dichas estructuras, reduciendo así su impacto e incrementando la seguridad. En este trabajo se describen el diseño, implementación, operación y funcionamiento de esta estación. También se calcula el índice de éxito en las series temporales más largas de cada una de las tres posibles ubicaciones descritas en la costa gallega: Cíes (boya oceánica frente a la Ría de Vigo), Catoira (boya continental en el río Ulla) y Cortegada (instalada en una batea en la Ría de Arousa)

Video-based assistance system for training in minimally invasive surgery

In this paper, the development of an assisting system for laparoscopic surgical training is presented. With this system, we expect to facilitate the training process at the first stages of training in laparoscopic surgery and to contribute to an objective evaluation of surgical skills. To achieve this, we propose the insertion of multimedia contents and outlines of work adapted to the level of experience of trainees and the detection of the movements of the laparoscopic instrument into the monitored image. A module to track the instrument is implemented focusing on the tip of the laparoscopic tool. This tracking method does not need the presence of artificial marks or special colours to distinguish the instruments. Similarly, the system has another method based on visual tracking to localize support multimedia content in a stable position of the field of vision. Therefore, this position of the support content is adapted to the movements of the camera or the working area. Experimental results are presented to show the feasibility of the proposed system for assisting in laparoscopic surgical training

Informe sobre los estudios realizados sobre las lesiones que afectan a diferentes elementos constructivos del Palacio de San Esteban, Murcia, y sobre la inspección efectuada sobre el mismo

Preprin

Prediction of the force of the ball-burnishing, physical model

En este artículo se desarrolla un modelo físico para predecir la fuerza en el bruñido con bola. El modelo está construido en base a la teoría de la plasticidad. En el desarrollo del modelo se ha encontrado el número adimesional B que caracteriza el problema de deformación plástica en el bruñido con bola. Los experimentos realizados en acero y aluminio permiten validar el modelo y destacar la correcta predicción de las tendencias de comportamiento del bruñido con bola.Postprint (published version

Solución analítica para el problema de deformación plástica de un cuerpo cilíndrico

En este artículo se relata la obtención de una solución para predecir la presión media hecha por una prensa en un proceso de recalcado de un cuerpo cilíndrico. La principal novedad en este trabajo es la consideración de la velocidad de la prensa en el modelo de deformación plástica y la estimación de la relación que tiene esta velocidad, con el endurecimiento por deformación. Los principales resultados son: Se ha podido estimar la presión media en un proceso de recalcado y el endurecimiento por deformación asociado, también se ha podido determinar las condiciones de operación, velocidad de la prensa y espesor de material de forma que no aparezca el fenómeno de endurecimiento por deformación.Postprint (published version

Ingeniería de procesos de fabricación

Postprint (published version

Economic Burden Associated with the Treatment with a Cardiovascular Polypill in Secondary Prevention in Spain: Cost-Effectiveness Results of the NEPTUNO Study.

PURPOSE The aim of this study was to estimate health-care resources utilization, costs and cost-effectiveness associated with the treatment with CNIC-Polypill as secondary prevention of atherosclerotic cardiovascular disease (ASCVD) compared to other treatments, in clinical practice in Spain. PATIENTS AND METHODS An observational, retrospective study was performed using medical records (economic results [healthcare perspective], NEPTUNO-study; BIG-PAC-database) of patients who initiated secondary prevention between 2015 and 2018. Patients were followed up to 2 years (maximum). Four cohorts were balanced with a propensity-score-matching (PSM): 1) CNIC-Polypill (aspirin+atorvastatin+ramipril), 2) Monocomponents (same separate drugs), 3) Equipotent (equipotent drugs) and 4) Other therapies ([OT], other cardiovascular drugs). Incidence of cardiovascular events, health-care resources utilization and healthcare and non-healthcare costs (2020 Euros) were compared. Incremental cost-effectiveness ratios per cardiovascular event avoided were estimated. RESULTS After PSM, 1614 patients were recruited in each study cohort. The accumulated incidence of cardiovascular events during the 24-month follow-up was lower in the CNIC-Polypill cohort vs the other cohorts (19.8% vs Monocomponents: 23.3%, Equipotent: 25.5% and OT: 26.8%; p<0.01). During the follow-up period, the CNIC-Polypill cohort also reduced the health-care resources utilization per patient compared to the other cohorts, particularly primary care visits (16.6 vs Monocomponents: 18.7, Equipotent: 18.9 and OT: 21.0; p<0.001) and hospitalization days (2.3 vs Monocomponents: 3.4, Equipotent: 3.7 and OT: 4.0; p<0.001). The treatment cost in the CNIC-Polypill cohort was lower than that in the other cohorts (€4668 vs Monocomponents: €5587; Equipotent: €5682 and OT: €6016; p<0.001) (Difference: -€919, -€1014 and -€1348, respectively). Due to the reduction of cardiovascular events and costs, the CNIC-Polypill is a dominant alternative compared to the other treatments. CONCLUSION CNIC-Polypill reduces recurrent major cardiovascular events and costs, being a cost-saving strategy as secondary prevention of ASCVD.This study was funded by Ferrer.S