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Integral Sensor Fault Detection and Isolation for Railway Traction Drive
Get PDFDue to the increasing importance of reliability and availability of electric traction drives in Railway applications, early detection of faults has become an important key for Railway traction drive manufacturers. Sensor faults are important sources of failures. Among the different fault diagnosis approaches, in this article an integral diagnosis strategy for sensors in traction drives is presented. Such strategy is composed of an observer-based approach for direct current (DC)-link voltage and catenary current sensors, a frequency analysis approach for motor current phase sensors and a hardware redundancy solution for speed sensors. None of them requires any hardware change requirement in the actual traction drive. All the fault detection and isolation approaches have been validated in a Hardware-in-the-loop platform comprising a Real Time Simulator and a commercial Traction Control Unit for a tram. In comparison to safety-critical systems in Aerospace applications, Railway applications do not need instantaneous detection, and the diagnosis is validated in a short time period for reliable decision. Combining the different approaches and existing hardware redundancy, an integral fault diagnosis solution is provided, to detect and isolate faults in all the sensors installed in the traction drive
Opportunities and incentives for Remanufacturing in the Basque Country
Get PDFRemanufacturing is a business model that helps the development of the circular economy. There are numerous successful examples of remanufactured products in different industrial sectors of Europe and US. Obtaining the maximum benefit of remanufacturing is related to the client recognizing the value of his assets at the end of its life, and that the manufacturer makes products that have the functionality and durability required. These aspects, can be improved if the remanufactured products are converted into a product-service systems (PSS). The objective of this research is to identify the opportunities, challenges, drivers and barriers for the development of remanufacturing activities in the main industrial sectors of the Basque Country. The research team has analysed
890 industrial companies, of which 197 companies have been identified the potential to development their remanufacturing process. After that, in order to know the reality of the different industrial sectors of the Basque Country, the research team developed a questionnaire oriented to the companies with the highest remanufacturing potential. In addition, they interviewed the industrial managers and directors of innovation of the 18 leading industrial companies in the Basque Country. The research team estimated that the remanufacturing process in the Basque Country is an emerging activity with great potential for development for 2025. The initial sales estimate for the five priority sectors analysed in 2016 is 63.6 million euros, and for 2025 is 163 million. According to the interviews, the main motivations that companies have for remanufacturing are strategic advantage and differentiation, high product value and high durability of the product. The main barriers identified are access to products, the resulting quality and market valuation
An ad-hoc fretting wear tribotester design for thin steel wires
Get PDFSteel wire ropes experience fretting wear damage when the rope runs over a sheave promoting an oscillatory motion between the wires. Consequently, wear scars appear between the contacting wires leading to an increase of the stress field and the following rupture of the wires due to fatigue. That is why the understanding and prediction of the fretting wear phenomena of thin wires is fundamental in order to improve the performance of steel wire ropes. The present research deals with the design of an ad-hoc fretting wear test machine for thin wires. The test apparatus is designed for testing thin wires with a maximum diameter of 1.0 mm, at slip amplitudes ranging from 5 to 300 μm, crossing angle between 0-90º, and contacting force ranging from 0,5 to 5 N. The working principle of displacement amplitude and contacting force as well as the crossing angle between the wires are described. Preliminary studies for understanding the fretting wear characteristics are presented, analysing 0.45 mm diameter cold-drawn eutectoid carbon steel (0.8% C) wires (tensilestrength higher than 3000 MPa)
Labor Induction failure prediction using Gabor filterbanks and Center Symmetric Local Binary Patterns
Get PDFLabor induction is defined as the artificial stimulation of uterine contractions aimed to induce vaginal birth. Occurring in about 20% of pregnancies labor induction has become one the most commonly practiced procedures in obstetrics. One of the risk related to labor induction is cesarean section which accounts about 20% of the inductions. A requirement for a successful labor is a ripe cervix (soft and distensible). Microestructural changes occurring in the cervix during the ripening process, will affect the interaction between cervical tissues and sound waves during ultrasound transvaginal scanning and will be perceived as gray level intensity variations in the echographic image. A non-invasive method using image processing of ultrasound images may help in predicting the outcome of labor induction. In this paper a set of echography images from labor induction patients is analyzed using a multiscale methodology based on Center Symmetric Local Binary Patterns and Gabor filters. Results show that it is feasible to predict the outcome of a labor induction procedure using this method with a good accuracy
Microstructural aspects of the transition between two regimes in orthogonal cutting of AISI 1045 steel
Get PDFIn depth understanding of tool-chip friction behavior is a significant aspect for tool wear performance in steels. In the present work attention has been paid to the strain mode of the chip section in contact with the rake surface of the tool, and its influence on the mechanics of material removal. There is a multitude of evidence for the existence of qualitatively different cutting regimes in orthogonal machining of annealed AISI-1045 steel with uncoated P15 carbide cutting tools in dry conditions at cutting speeds between 5 and 200 m/min. The evaluation of chip morphology and microstructure, and cutting and feed forces, revealed an abrupt step-like transition at a cutting speed in the range of 50–60 m/min, which was attributed to the transition from built-up edge (BUE) mode developed at low cutting speed, to the mode at which the chip slides directly over the tool surface. These qualitatively distinct mechanisms of tool-chip interaction are determined by two different microstructural effects: work hardening by severe plastic deformation and microstructural softening by dynamic recrystallization (DRX). It is argued that the onset of DRX is the reason for further instability of BUE and thus is the main cause of change of the cutting regime
La implicación del profesorado universitario en procesos de innovación educativa: un estudio en Mondragon Unibertsitatea
Get PDFEl desconcierto que la incertidumbre de este mundo cambiante produce, junto con la naturaleza caduca del
conocimiento, invita a replantearnos la funcionalidad y el desarrollo del modelo educativo vigente en la
sociedad contemporánea. La educación es la herramienta facilitadora sobre la que la sociedad se fundamenta
para su desarrollo. Es por ello por lo que creemos que un cambio significativo en su planteamiento y
tratamiento, mediante procesos de innovación educativa, puede dar respuesta a las nuevas y numerosas
necesidades propuestas. Desde Mondragón Unibertsitatea apostamos por un modelo educativo trasformador.
Un modelo educativo cuyo eje vertebrador es la persona y su capacidad para gestionar la información, construir
conocimiento y utilizarlo para responder así a estos actuales, considerables y numerosos retos. Igualmente,
creemos que estos procesos de innovación educativa que sitúan al alumnado en el centro del foco sugieren
cambios significativos en los posicionamientos de los docentes, por lo que realizar un análisis sobre la
repercusión que los procesos de innovación educativa tienen en la implicación del profesorado, y viceversa,
además de ser un ejercicio novedoso que pueda aportar conocimiento en el ámbito de la investigación
educativa, resulta atrayente.
El objetivo de esta investigación en desarrollo, por tanto, es describir, analizar e interpretar la repercusión o el
efecto de la implicación del profesorado universitario en los procesos de innovación educativa y de igual
manera, analizar, describir e interpretar el efecto que la participación en proyectos de innovación educativa
tiene en la implicación del profesorado universitario. Todo esto, teniendo en cuenta los procesos de
construcción de la identidad.
La metodología de esta investigación de corte cualitativo es un estudio de caso con enfoque narrativo, basado
en relatos autobiográficos, entrevistas en profundidad, grupos de discusión, entre otras
Tokiko kultura-ondarea lantzeko pedagogia- eta didaktika-eredu baten beharra
Get PDFPedagogia- eta didaktika-eredu berrien beharrean gaude; irakasleok horretaz
jarduteko, ondarearen hezkuntzara garamatzan markoa ere diseinatu behar dugu.
Hala, artikulu honek bi helburu ditu: ondarearen eta hezkuntzaren arteko balioetan
sakontzea, eta diseinurako gakoak (genealogia, irakaslea, ikaslea, testuingurua eta
edukia) identifikatu eta ezaugarritzea. Izan ere, hezkuntza-sistema modernoaren
krisiarekin topo egin dugu azken aro honetan. Pedagogia-paradigma berrien
beharrean gaude, non familiaren, eskolaren, komunitate osoaren inplikazioa
beharrezkoa den, baina aurrekoari uko egin gabe, transmisioa bertan behera laga
gabe. Esan nahi da gure ingurune soziokulturaleko ikasketa esanguratsuak erraztu
eta sustatzeko ardura dugula hezitzaileok; hots, konpromiso bat daukagula ikaslearen
nahiz irakaslearen identitatearen parte den natura- eta kultura-ondarearekin.We need new pedagogical and didactic models; in order for teachers to act on this,
we must also design a framework that will lead us to heritage education. Therefore, this article
has two aims. First, to examine the values that link heritage and education and then second,
to identify and characterise keys for design (genealogy, teacher, student, context and content). In fact, we have found the modern educational system to be in crisis in recent times. We
are in need of new pedagogical paradigms in which the involvement of family, school, and the
entire community is essential, and in which this involvement is maintained without abandoning
the transmission of knowledge. This means ensuring that educators will be responsible for facilitating and promoting meaningful studies on our socio-cultural environment; that is, studies
that include the natural and cultural heritage that forms a part of the identity of both students
and teachers
Opportunities and policy challenges of digital economy to small regions: the case of Gipuzkoa
Get PDFNations and territories have new and varied challenges with respect to promoting continuous growth in the economy. The purpose of this article is to determine the opportunities and difficulties faced by the territory of Gipuzkoa in the field of economics. In interviews and focus groups with the principle agents of the territory, the unified commitment to industry over the last decades is unanimously appreciated. This commitment involves the complete transformation of the social and economic structure of the territory. However, disparities in business dynamism are evident, and the capacities and resources of companies to bring industry up to date in the digital economy and respond to new competitive factors are very different. This being the case, different perspectives are emerging to respond to challenges among agents. Nevertheless, two general issues are agreed upon: the territory is conceptualized as an active agent, and the need for updating the innovation system is recognized. This makes it possible to share strategies and to respond in a cooperative way to productive specialization.Las naciones y los territorios tienen nuevos y variados desafíos con respecto a la promoción del crecimiento continuo en la economía. El propósito de este artículo es determinar las oportunidades y dificultades que enfrenta el territorio de Gipuzkoa en el campo de la economía. En entrevistas y grupos de discsuón con los principales agentes del territorio, se aprecia unánimemente el compromiso unificado con la industria en las últimas décadas. Este compromiso implica la transformación completa de la estructura social y económica del territorio. Sin embargo, las disparidades en el dinamismo empresarial son evidentes, y las capacidades y recursos de las empresas para actualizar la industria en la economía digital y responder a los nuevos factores competitivos son muy diferentes. Siendo este el caso, están surgiendo diferentes perspectivas para responder a los desafíos entre los agentes. Sin embargo, se acuerdan dos cuestiones generales: el territorio se conceptualiza como un agente activo y se reconoce la necesidad de actualizar el sistema de innovación. Esto permite compartir estrategias y responder de manera cooperativa a la especialización productiva
Material management without forecasting: From MRP to demand driven MRP
Get PDFPurpose: Efficient Operations and Supply Chain Management is key to building sustainable competitive edge for companies. However, the achievement of this goal is becoming challenging in the present dynamic production environment, as traditional Manufacturing Planning and Control systems were not developed to work in this context. The Demand-Driven Material Requirement Planning (DDMRP) methodology was developed with the aim of addressing this need and deal efficiently with material management. The present work therefore, analyzes the implemented changes and the subsequent qualitative and quantitative results of a company after converting from MRP to DDMRP.
Design/methodology/approach: To achieve an in depth understanding of the case study a qualitative approach was taken. Data was collected from semi-structured interviews, documents and archival records enabling triangulation. The results from before and after the implementation of DDMRP were compared, and the evolution of the performance of the company was evaluated.
Findings: The results clearly show that using DDMRP the company increased visibility in the supply chain. In addition, the inventory level was reduced by 52.53% while material consumption was increased by 8.7%. These results were achieved while maintaining the high service level.
Originality/value: DDMRP is a relatively new methodology and for this reason there is little published data in this field. In addition the few studies found in the literature analyze the performance of DDMRP in simulated environments. The present work aims to go one step further and analyzes the implementation of DDMRP in a real company
Frequency-Dependent Pi Model of a Three-Core Submarine Cable for Time and Frequency Domain Analysis
Get PDFIn this paper, a Frequency-Dependent Pi Model (FDPi) of a three-core submarine cable is presented. The model is intended to be used for the representation of submarine cables in an Offshore Wind Power Plant (OWPP) scenario for both time and frequency domain analysis. The frequency-dependent variation of each conductive layer is modeled by a Foster equivalent network whose parameters are tuned by means of Vector Fitting (VF) algorithm. The complete formulation for the parameterization of the model is presented in detail, which allows an easy reproduction of the presented model. The validation of the model is performed via a comparison with a well-established reference model, the Universal Line Model (ULM) from PSCAD/EMTDC software. Two cable system case studies are presented. The first case study shows the response of the FDPi Model for a three-core submarine cable. On the other hand, the second case study depicts the response of three single-core underground cables laying in trefoil formation. This last case shows the applicability of the FDPi Model to other types of cable systems and indirectly validates the response of the aforementioned model with experimental results. Additionally, potential applications of the FDPi model are presented