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Pertsona burujabea Arizmendiarrietaren asmoan eta egitean
Get PDFArizmendiarrietaren pentsaeran eta jokabidean pertsona burujabea gai zentrala da. Ideia hori ulertzeko argibideak ematen dira, Azurmendik gizakiaren historiaz eta moralaz irakatsitakoak bidelagun hartuta
Monitoring of a Hammer Forging Testing Machine for High-Speed Material Characterization
Get PDFDynamic testing of materials is necessary to model high-speed forming processes (i.e. hammer forging, blanking) and crash/impact behavior of structures, among others. The most common machines to perform medium to high-speed tests are the servo-hydraulic high-speed tensile and compression machines and the Hopkinson bars. The paper analyses the possibility to use a laboratory forging hammer for the characterization of materials at medium and high strain rates. For this, an automatized forging hammer has been constructed which is accelerated with a pneumatic cylinder and is able to speed up the upper anvil up to 5 m/s. This forging testing machine can be employed to perform a variety of material characterization tests, such as, uniaxial upsetting tests, plane strain compression tests as well as crash tests. To ensure the correctness of the experimental results obtained from tests performed in this home-developed laboratory facility, it is essential to verify and validate the acquired data. With this aim, copper cylindrical specimens have been deformed at different speeds. A high-speed camera has been employed to monitor real specimen strains using DIC and a load cell has been also utilized to measure the force applied during deformation. In order to obtain valid material rheological results, force data obtained from the load cell has been combined with DIC strain data to draw reference flow curves. Analogous stress-strain values have been calculated analytically using both techniques independently, solely high-speed camera data, on the one hand, and only load-cell data, on the other hand. A comparison of results has been performed and discussed in order to select the best monitoring technique to implement in the laboratory forging hammer
Programa KoopFabrika (Gipuzkoa y Bizkaia) = KoopFabrika Programa (Gipuzkoa eta Bizkaia)
No full textKoopFabrika es un programa de fomento y
promoción de la economía social y el emprendimiento cooperativo para iniciativas surgidas en el Territorio Histórico de Gipuzkoa cuya primera edición se impartió en el curso 2016-2017 promovido por el Instituto Lanki de la Universidad de Mondragón,
Olatukoop (https://olatukoop.eus) y el Instituto Gezki de la Universidad
del País Vasco (UPV/EHU). En el curso 2019-2020
se ha iniciado en Bizkaia esta experiencia en coordinación con REAS
Euskadi, Olatukoop y otras entidades.
El programa trata de combinar tres ejes de actuación principales, junto
con dos actividades complementarias que fortalecen y extienden la
experiencia. Los tres ejes de actuación que se orientan a los emprendimientos
cooperativos dentro del programa son: la formación, la tutorización y el
“hacer red”.KoopFabrika ekonomia sozial eta ekintzailetza
kooperatiboa sustatzeko programa bat da, Gipuzkoako Lurralde
Historikoan sortutako ekimenetara zuzendua. Bere lehen edizioa 2016-2017
ikasturtean izan zen Lanki Institutuak (MU), Olatukoop eta Gezki Institutuak (EHU) bultzatuta. 2019-2020 ikasturtean ekin zaio
ekimenari Bizkaian REAS Euskadi, Olatukoop eta
beste erakunde batzuekin koordinatuta.
Programak hiru jarduera-ardatz nagusi, eta esperientzia indartzen eta
hedatzen duten bi jarduera gehigarri konbinatzen ditu. Programaren
barruan ekimen kooperatiboetara zuzentzen diren hiru jarduera-ardatz
nagusiak dira prestakuntza, tutoretza eta saregintza
Optical Dual Laser Based Sensor Denoising for OnlineMetal Sheet Flatness Measurement Using Hermite Interpolation
Get PDFFlatness sensors are required for quality control of metal sheets obtained from steel coils by roller leveling and cutting systems. This article presents an innovative system for real-time robust surface estimation of flattened metal sheets composed of two line lasers and a conventional 2D camera. Laser plane triangulation is used for surface height retrieval along virtual surface fibers. The dual laser allows instantaneous robust and quick estimation of the fiber height derivatives. Hermite cubic interpolation along the fibers allows real-time surface estimation and high frequency noise removal. Noise sources are the vibrations induced in the sheet by its movements during the process and some mechanical events, such as cutting into separate pieces. The system is validated
on synthetic surfaces that simulate the most critical noise sources and on real data obtained from the installation of the sensor in an actual steel mill. In the comparison with conventional filtering methods, we achieve at least a 41% of improvement in the accuracy of the surface reconstruction
Interpreting Remaining Useful Life estimations combining Explainable Artificial Intelligence and domain knowledge in industrial machinery
Get PDFThis paper presents the implementation and explanations of a remaining life estimator model based on machine learning, applied to industrial data. Concretely, the model has been applied to a bushings testbed, where fatigue life tests are performed to find more suitable bushing characteristics. Different regressors have been compared Environmental and Operational Condition and setting variables as input data to prognosticate the remaining life on each observation during fatigue tests, where final model is a Random Forest was chosen given its accuracy and explainability potential. The model creation, optimisation and interpretation has been guided combining eXplainable Artificial Intelligence with domain knowledge.
Precisely, ELI5 and LIME explainable techniques have been used to perform local and global explanations. These were used to understand the relevance of predictor variables in individual and overall remaining life estimations. The achieved results have been process knowledge gain and expert knowledge validation, assertion of huge potential of data-driven models in industrial processes and highlight the need of collaboration between expert knowledge technicians and eXplainable Artificial Intelligence techniques to understand advanced machine learning models
Integrando las dimensiones de la experiencia de paciente en proyectos de diseño centrado en las personas
Get PDFDiversas investigaciones apuntan que una eXperiencia de Paciente (PX) positiva mejora los resultados de salud y la rentabilidad de los centros médicos. Uno de los enfoques utilizados para mejorar la PX es el diseño centrado en las personas (HCD), ya que posee métodos participativos, multidisciplinares y efectivos para proponer nuevos productos y servicios en base a la experiencia de las personas. Por otro lado, las instituciones médicas se rigen por un enfoque de atención centrada en la persona y miden la PX con las denominadas PREMs, cuestionarios validados que ayudan a identificar las dimensiones de la PX a mejorar. El objetivo es examinar si los proyectos realizados con métodos HCD identifican las mismas dimensiones que evalúan estos cuestionarios. Se ha realizado un estudio utilizando métodos HCD donde se recogió, analizó y contrastaron los datos obtenidos sobre las dimensiones de la PX. El estudio indica que los métodos HCD no identificaron claramente el mismo número de dimensiones definidas por las encuestas sobre PX. Para integrar de forma efectiva las dimensiones de la PX en los proyectos de HCD, se proponen tres líneas de trabajo posibles para guiar a los equipos de diseño de forma efectiva en proyectos de salud
Framework to evaluate continuous improvement process efficacy: a case study of a capital goods company
Get PDFPurpose: This document describes a continuous improvement process assessment system (CIPAS). A continuous improvement process (CIP) was developed to progress through the levels of continuous improvement (CI) defined by Bessant, Caffyn and Gallagher (2001), and the CIPAS was developed to measure this evolution. The CIP and the CIPAS were tested in a mature industrial small and medium-sized enterprise (SME) cooperative company (Basque Country, Spain) that works in the capital goods sector. Methodology/Approach: The study was developed according to an ‘action research’ strategy (Coughlan and Coghlan, 2002) over a period of two years. The action research team includes the authors and managers of several areas of the studied company. Findings: The assessment identified critical elements and related routines for the effective execution of the CIP in this company. In addition, the evaluation system allowed for a visualisation of the company’s CI maturity level progression. Research Limitation/implication: The assessment system was designed in an ad hoc manner for this CIP and this industrial company, but it may be possible to adapt these to other types of companies by using the steps followed and indicators defined as an example. Originality/Value of paper: The CIPAS is used to identify the key CI elements, to measure the evolution of CI routines, and to identify a CI maturity level of the company in which the CIP is applied. It can be applied to any type of company and serves to define future actions for its evolution.
Category: Case stud
A population-specific material model for sagittal craniosynostosis to predict surgical shape outcomes
Get PDFSagittal craniosynostosis consists of premature fusion (ossification) of the sagittal suture during infancy, resulting in head deformity and brain growth restriction. Spring-assisted cranioplasty (SAC) entails skull incisions to free the fused suture and insertion of two springs (metallic distractors) to promote cranial reshaping. Although safe and effective, SAC outcomes remain uncertain. We aimed hereby to obtain and validate a skull material model for SAC outcome prediction. Computed
tomography data relative to 18 patients were processed to simulate surgical cuts and spring location. A rescaling model for age matching was created using retrospective data and validated. Design of experiments was used to assess the effect of different material property parameters on the model output. Subsequent material optimization—using retrospective clinical spring measurements—was performed for nine patients. A population-derived material model was obtained and applied to the whole population. Results showed that bone Young’s modulus and relaxation modulus had the largest effect on the model predictions: the use of the population-derived material model had a negligible effect on improving the prediction of on-table opening while significantly improved the prediction of spring kinematics at follow-up. The model was validated using on-table 3D scans for nine patients: the predicted head shape approximated within 2 mm the 3D scan model in 80% of the surface points, in 8 out of 9 patients. The accuracy and reliability of the developed computational model of SAC were increased using population data: this tool is now ready for prospective clinical application
A Hybrid Sensor Fault Diagnosis for Maintenance in Railway Traction Drives
Get PDFDue to the importance of sensors in railway traction drives availability, sensor fault diagnosis has become a key point in order tomove frompreventivemaintenance to condition-basedmaintenance. Most research works are limited to sensor fault detection and isolation, but only a few of them analyze the types of sensor faults, such as offset or gain, with the aim of reconfiguring the sensor in order to implement a fault tolerant system. This article is based on a fusion of model-based and data-driven techniques. First, an observer-based approach, using a Sliding Mode observer, is utilized for sensor fault reconstruction in real time. Then, once the fault is detected, a timewindowof sensormeasurements and sensor fault reconstruction is sent to the remotemaintenance center for fault evaluation. Finally, an offline processing is carried out to discriminate between gain and offset sensor faults, in order to get a maintenance decision-making to reconfigure the sensor during the next train stop. Fault classification is done by means of histograms and statistics. The technique here proposed is applied to the DC-link voltage sensor in a railway traction drive and is validated in a hardware-in-the-loop platform