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A Design Thinking approach to introduce entrepreneurship education in European school curricula
Get PDFDesign Thinking is visualized as the central strategy to promote entrepreneurial skills in European schools. Europe needs future generations to be more entrepreneurial in their attitudes to achieve a strong position in the international economy. Entrepreneurial thinking needs to be fostered from an early age. With this aim, a review of current entrepreneurial teaching practices is undertaken and the key skills related to entrepreneurship are identified for school aged students. This paper argues that the basic principles of Design Thinking have the potential to promote entrepreneurial competencies in European school curricula
Konpetentzia digitalaren planteamenduaren azterketa EKI proiektuan
Get PDFIkerketa honen helburuak dira Ikastolen Elkarteak garatu duen EKI ikas-materialean konpetentzia
digitala nola jasotzen den ikustea eta materialarekiko ikasle eta irakasleen ahotsak jasotzea. EKI
proiektuan baliatu den ikasmateriala euskarri digitalean zein analogikoan aurki daiteke eta ikerketa
honen bidez, batean zein bestean, konpetentzia digitala nola ulertzen den, euskarriari zein
inplementazioari dagokionez, proiektuaren indar-gune eta ahulguneak zeintzuk izan diren identifikatu
da. Lortutako emaitzak, orokorrean, nazioarteko testuinguruan burututako beste ikerketa batzuen
antzerakoak dira. Ondorioek adierazten dute informazio eta komunikazio teknologiek (IKT) ikasgela
barruan nahiz kanpoan, irakasle-ikasleen jardunaren antolaketan eragiten dutela, baina horiek
baliatzeak ez duela zertan berrikuntza pedagogiko esanguratsua izan irakasleen praktikari dagokionez.The aim of this research is to present the opinion of the teachers and students in relation to the
teaching material called EKI, developed by Ikastolen Elkartea. We can find the teaching material in
digital or analogical format. The research describes the strongholds and weakness of digital
competence with regard to teaching material format and implementation. The results achieved are
similar to international research ones. The results point out that ICT changes the teachers and students
way of organise the task, but that does not mean any pedagogical innovation in respect to teachers
practice
DC-link sensor Fault Detection and isolation for railway traction electric drives
Get PDFThis article presents the design and the implementation of a fault detection and isolation strategy for sensors in variable speed drives. Electric drives use several current and voltage sensors for control and protection. The principal objective of the strategy is to detect faults in DC-Link sensors, since the conclusion of a preliminary study showed that in some applications many functionalities in the control strategy depend on it. Although it was mainly designed for DC-Link sensors, thanks to the FDI structure presented here, the algorithm is able to detect faults in other sensors. The strategy is based on state observers and has been validated through real time simulations in a Hardware-in-the-Loop platform. The principal components of the platform are an OPAL-RT real time simulator and a commercial traction control unit
Next generation of tools for industry to evaluate the user emotional perception: the biometric-based multimethod tools
Get PDFNumerical simulation of U-Drawing test of Fortiform 1050 steel using different material models
Get PDFSteel has been used in vehicles from the automotive industry's inception. Different steel grades are continually being developed
in order to satisfy new fuel economy requirements. For example, advanced high strength steel grades (AHSS) are widely used
due to their good strength/weight ratio. Because each steel grade has a different microstructure composition and hardness, they show different behaviors when they are subjected to different strain paths. Similarly, the friction behavior when using different contact pressures and sliding velocities is considerably altered.
Third generation steels present high yield strength together with high elongation capacity and strain hardening. Thus, it is logical to think that elastic modulus reduction and Bauschinger effect are important aspects when stamping these materials. Furthermore, high contact pressures arise when forming these steels and friction coefficient may significantly influence the numerical results.
Stamping forming processes are nowadays usually optimized by numerical tools such as Finite Element Models. In order to get reliable results, these numerical tools require proper material and contact models in order to correctly predict the real behavior and flow of the materials.
In the present paper, Fortiform 1050 material is deeply characterized using uniaxial and cyclic tension-compression tests. Friction coefficient is obtained using
strip drawing tests. These results have been used to calibrate mixed kinematic-hardening material models as well as the friction. Finally, the geometrical accuracy of the different material models has been obtained by means of the comparison of the numerical predictions with experimental demonstrators obtained using a U-Drawing tester
Development of Tools to Calculate the Vibroacoustic Performance of Electrical Machines in Lift Installations
Get PDFImproper operation of the traction machine of a lift installation causes energy waste, vibrations and noise. The design of the machine must be optimum if energy efficiency and comfort specifications have to be satisfied. The vibrations and noise frequency spectra of electrical machines present manifest peaks at certain frequencies, multiples of the fundamental electrical frequency, that depend on the machine topology and its rotation velocity. Changes in its topology or in its mechanical properties (geometry, size, materials…) must be done in order to reduce the magnitude of peaks at certain excitation frequencies or to locate the excitation frequencies far from the natural frequencies of the structure or the lift installation. Machine designers need tools to calculate their vibroacoustic response once a certain design has been proposed, so they can modify it before a prototype is built in case the response is not acceptable. Numerical and analytical models to calculate the vibroacoustic response of electrical machines have been developed and experimentally validated. In this paper, the authors summarise the state of the art in modelling the vibroacoustic performance of electrical machines, provide some guidelines regarding the values to be assigned to the machine componets, and show some of the results obtained in their research work
A Coupled Eulerian Lagrangian Model to Predict Fundamental Process Variables and Wear Rate on Ferrite-pearlite Steels
Get PDFA coupled Eulerian-Lagrangian Finite Element model of the orthogonal cutting process was developed to predict the influence that ferritepearlite steel variants have on fundamental process variables and tool wear. As a case study, this paper is focused on two different ferritepearlite inclusion free alloys, where mainly the influence of ferrite-pearlite ratio was tested. Flow stress behavior based on dynamic compression tests and thermal properties function of temperature were characterized for model input parameters. The numerical model is compared with orthogonal cutting tests where the cutting and feed forces, tool temperature, chip morphology and tool wear related variables were measured. Globally, predicted tendencies match with experiments in forces and temperatures. Widest differences on predictions were found for chip thickness and tool-chip contact length. Predicted wear rates are in accordance to experimentally measured values
Euskarazko tokiko komunikabideen egoerari begirada bat
Get PDFArtikulu honen helburua da euskarazko tokiko komunikabideen egoeraren aurkezpen berritu bat egitea, azken hiruzpalau urteetan komunikabide batzuk sortu edota bateratu direlako, bereziki. Arreta jarri da sortutako komunikabide berrietan eta, bereziki, Tolosaldeko Ataria komunikabidearen egoera deskribatu da. Horrez gain, ekoizpen datuak eta Interneteko audientziak begiratu dira
Press hardening of alternative materials: conventional high- strength steels
Get PDFhe increase in strength of new high strength steels(HHS) and advanced high strength steels (AHHS) has led toforming issues, such as high springback, low formability, increase of forming forces and tool wear. These problems increase thecosts of manufacturing and maintainingstamping tools in the automotive industry. The aim of this research was to analyse the advantages of applyingthe press-hardening process toconventional HSS and AHSS steel to increase their formability and therefore reduce thenumber of forming steps and productioncosts. With this aimin mind, the press-hardening process was used to manufacturean industrialcomponent using four different automotive steelgrades: dual phase (DP),complex phase (CP), transformation-induced plasticity (TRIP) and martensitic (MS) grade.Springback measurements werecarried out, together with ananalysis of the obtained final mechanical properties and microstructures. The results showed that the formability of all thematerials increased. The mechanical properties of theCP800and TRIP700 materials were maintained or even improved, whereas those of the MS1200 and HCT980Xmaterials were significantly reduced. Weconclude thatpress hardening is a suitable manufacturing processforCP800 and TRIP700components
Euskara, generoa, klasea eta jatorria eskolan. Zenbait gogoeta
Get PDFDemagun gizarte justuago bat eraiki nahi dugula (hitzaldi
hau jaso duen jardunaldiaren helburua hori dela
esango nuke). Lau desparekotasun soziopolitiko ditugu
aurrean, eta badakigu haien artean gurutzatzen direla;
eskolan gurutzatzen dira une oro, etengabe. Jakina
da eskola aniztasunaren eremua dela (hori da behintzat
eskola inklusiboaren paradigma); baina bada, halaber,
desberdinkeriaren eremua. Horretaz arituko naiz hurrengo
lerroetan