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Equivalence of primary control strategies for AC and DC microgrids
Get PDFMicrogrid frequency and voltage regulation is a challenging task, as classical generators with rotational inertia are usually replaced by converter-interfaced systems that inherently do not provide any inertial response. The aim of this paper is to analyse and compare autonomous primary control techniques for alternating current (AC) and direct current (DC) microgrids that improve this transient behaviour. In this context, a virtual synchronous machine (VSM) technique is investigated for AC microgrids, and its behaviour for different values of emulated inertia and droop slopes is tested. Regarding DC microgrids, a virtual-impedance-based algorithm inspired by the operation concept of VSMs is proposed. The results demonstrate that the proposed strategy can be configured to have an analogous behaviour to VSM techniques by varying the control parameters of the integrated virtual-impedances. This means that the steady-state and transient behaviour of converters employing these strategies can be configured independently. As shown in the simulations, this is an interesting feature that could be, for instance, employed for the integration of different dynamic generation or storage systems, such as batteries or supercapacitors
Stability and parking cross distance adapter mechanism for electric vehicle
Get PDFDue to the actual vehicle dimensions, low occupancy rates and the increase of world population, a trend to develop new vehicle concepts with smaller dimensions is seen. The objective of this trend is to reduce traffic congestion and park ability related issues in overpopulated areas. Not only footprint reduction is necessary, but also maintaining actual vehicle safety and comfort metrics is a must. Therefore, first of all, a mechanism to reduce wheel track to the third of the space required for a conventional car for low speed and parking
situations is designed and developed. Once the track variation mechanism is completely defined, several suspensions and steering mechanism are analysed, concluding with a design of an unconventional front independent suspension and steering systems which are detailed in the present manuscript. By using MBS (Multi-body System) model, loads transmitted from tyre through mechanism joints to the vehicle chassis are computed. Special attention has been paid to the maximum peak loads that mechanism will suffer from road irregularities in extreme conditions. These load values are also used to evaluate the components that compose the track variation mechanism.
Continuing with the actuation of the system, an electronic control strategy is created and virtually tested, with what vehicle track position and vehicle speed and acceleration conditions are instantaneously controlled and related with the wheel track variation system.
Finally, the complete track width variation mechanism is manufactured, assembled and tested in a test rig
Uxer: Nueva herramienta para la evaluación heurística de la experiencia en entornos interactivos y digitales
Get PDFThe digital interfaces have become the spaces that more interactive flows are generated between products/services and people. The latest proposals allow us to control an entire building, a production facility or execute complex actions that have not traditionally been implemented by a digital drive. The society is immersed in the digitization era along with a quick evolution of interactive environments and this has increased the complexity of use of digital products and services. In this context, this communication presents Uxer: a new tool that seeks to strengthen the technological companies in the field of digital evaluation of their proposals. Thus, the article presents a new agile and reliable support tool to strengthen the evaluation of usability and the experience of digital environments, which is based on the heuristic principles of usability.Las interfaces digitales se han convertido en los espacios que mayor número de flujos interactivos se generan entre productos/servicios y personas. Las últimas propuestas nos permiten controlar todo un edificio, una planta de producción o ejecutar complejas acciones que tradicionalmente no se han ejecutado mediante accionamiento digital. La sociedad está inmersa en la digitalización de la información junto con una rápida evolución de los entornos interactivos y esto hace que haya incrementado la complejidad de uso de los productos y servicios digitales.
En este contexto, esta comunicación presenta Uxer: una nueva herramienta que pretende fortalecer las carencias que presentan las empresas del sector tecnológico en el campo de la evaluación y testeo de sus propuestas. Así, el artículo presenta una nueva herramienta de apoyo ágil y fiable para fortalecer la evaluación de la usabilidad y la experiencia de uso digital, que está basado en los principios heurísticos de la usabilidad
EIEH: Industriako interakzio digitalak diseinatzeko erraminta berria
Get PDFIn recent years, due to the socio-economic development, the wishes of the society have been changing. Nowadays, instead of material goods, the society is looking for emotional and social goods. As a consequence, the market has developed beyond products and services, focusing on offering Experiences. So in design, as it is a discipline directly connected to the environment, the same development has occurred. However, in industry there is still a long way to go in order to integrate the concept of Experience in their developments. Therefore, there is a big gap regarding to Experience Design methods and tools for the industrial digital systems. In this context, Diseinu Berrikuntza Zentroa of Mondragon University (DBZ-MU) together with DANOBATGROUP S.COOP, is working on the creation of new tools for the development of the Experiences of those digital systems. In this article, one of those tools is presented, the User Interface Experience Capturer (UIEC). Thanks to this tool it is possible to capture the experiences that the user has with the interactive systems, so that way afterwards an interaction that fulfils the motivations and emotional needs of the user could be created.Azken urteotako aldaketa sozio-ekonomikoa dela eta, gizartearen nahiak aldatuz joan dira. Gaur egun, behar materialak baino, gizarteak beharrizan emozional eta sozialak betetzea ditu helburu, ondorioz, merkatuak produktu eta zerbitzuetatik haratago doan eboluzioa jasan du, esperientziak eskaintzean zentratuz. Neurri berean, diseinuan, inguruari guztiz lotutako disziplina izanik, esperientziaren alorrean ari da lanean. Hala ere, industria, behar guztiz materialetara zuzenduta egonik, egoera honetara egokitzeke dago oraindik. Horren erakusle, bertako inguru digitaletako esperientzien diseinurako metodo eta erraminten hutsune handia dagoela identifikatu da. Kontestu honen baitan, Mondragon Unibertsitateako Diseinu Berrikuntza Zentroa (DBZ-MU) DANOBATGROUP S.COOP-ekin elkarlanean, inguru digital horien esperientziara bideratutako erraminten sorreran ari da lanean. Horren adibide da artikulu honetan aurkezten den erraminta, Erabiltzaile Interfazeen Esperientzia Hartzailea (EIEH). Erraminta honi esker, erabiltzaileak sistema interaktiboekin dituen esperientziak jasotzen dira, ondoren bere motibazioak betetzen dituen eta lotura emozional eraginkorragoa ahalbidetzen dituen interakzio berriak diseinatu ahal izateko
A Performance Study of a Horizontal-axis Micro-turbine in a Numerical Wave Flume
Get PDFNumerical studies of performance of a 3-bladed Savonius type horizontal-axis wave energy converter are presented. Numerical simulations based on a volume of fluid (VOF) method coupled with a finite volume method (FVM) approach are performed in a numerical wave flume (NWF) for specified values of flow physics and turbine blade geometry conditions. Once validated against experimental data, the numerical simulations are extended to investigate the overall performance of the turbine over a very large range of wave height, wave frequency, and the submergence level for the same water depth in the context of optimization of a design of a small scale Savonius rotor. From the numerical results obtained and validated against the experimental data it can be concluded that the flow characteristics are strongly dependent upon differing wave propagation conditions and energy conversion rate can be increased with a proper combination of selected wave height and frequency for the investigated parametric value range
Investigación e innovación responsables: retos teóricos y políticos
Get PDFEl artículo valora las nuevas vías para conceptualizar las relaciones entre ciencia, tecnología, políticas
públicas y sociedad. Los Estudios de Ciencia y Tecnología anticipan modelos alternativos para comprender la
gobernanza de la ciencia. Por su parte, en el ámbito institucional en el seno de la estrategia “Horizonte 2020”
adquiere relevancia el lenguaje político asociado a la investigación y la innovación responsables (IIR) y se
reclama que las actividades de investigación e ingeniería deben alinear mejor su proceso y resultados con los
valores, las necesidades y las expectativas de la sociedad europea. El artículo establece un diálogo crítico entre
los avances teóricos y el nuevo lenguaje político y sugiere que el significado, alcance y aplicación de un enfoque
IIR dependerá de las dinámicas económicas y sociopolíticas por las cuales se instrumentalizan y regulan la
ciencia y la tecnología.O presente artigo valoriza as novas vias para conceber as relações entre ciência, tecnologia, política
pública e sociedade. Os Estudos de Ciência e Tecnologia antecipam modelos alternativos para compreender a
governança da ciência. Por seu lado, no âmbito institucional no seio da estratégia “Horizonte 2020” adquire
relevância a linguagem política associada à investigação e inovação responsáveis (IIR) e defende-se que as
atividades de investigação e engenharia devem alinhar melhor o seu processo e resultados com os valores, as
necessidades e as expectativas da sociedade europeia. O artigo estabelece um diálogo crítico entre os avanços
teóricos e a nova linguagem política e sugere que o significado, alcance e aplicação dum enfoque IIR dependerá
das dinâmicas económicas e sociopolíticas pelas quais se instrumentalizam e regulam a ciência e a tecnologia.The present article postulates the value of the new ways of looking at the relations between science,
technology, public / policies and society. On the one hand, Science and Technology Studies / foreshadow
/ alternative models for understanding the governance of science. On the other, within the institutional
framework at the heart of the “Horizon 2020” strategy, the political language associated with responsible
research and innovation (RRI) is gaining in importance, arguing that those who engage in research and
engineering activities should do a better job of aligning their processes and outcomes with the values, needs and
expectations of European society. The article offers a critical dialogue between the theoretical advances and the
new political language, and suggests that the significance, scope and application of an RRI-based focus will
depend on the economic and sociopolitical dynamics by which science and technology are instrumentalised and
regulated.Cet article aborde les nouvelles voies pour concevoir les relations entre science, technologie, politique
publique et société. Les Études de Science et Technologie proposent des modèles alternatifs pour comprendre la
gouvernance de la science. Pour sa part, dans le cadre institutionnel de la stratégie “Horizon 2020”, le langage
politique associé à la recherche et à l’innovation responsables (RRI) prend de l’importance, en défendant que les
activités de recherche et d’innovation doivent aligner davantage leurs processus et leurs résultats sur les valeurs,
les besoins et les attentes de la société européenne. L’article établit un dialogue critique entre les avancées
théoriques et le nouveau langage politique et suggère que le sens, la portée et l’application RRI dépendront des
dynamiques économiques et sociopolitiques par lesquelles la science et la technologie sont instrumentalisées et
régulées
Hizkuntzen arteko elkarreragina: Zer nolako hizkuntza baliabide transferitzen dituzte Lehen Hezkuntzako ikasleek euskara ikasteko garaian?
Get PDFAzken urteetan egoera eta testuinguru desberdinetan ikertu da etxeko hizkuntzak eta bigarren
hizkuntzak hirugarren hizkuntzaren ikasketa prozesuan izan dezaketen eragina. Gauzatutako
ikerketetan ondorioztatu da hizkuntza ikasleek transferitzen dituztela aurretiaz garatutako errekurtso
linguistikoak ikasten ari diren hizkuntzara. Artikulu honetan, hiztun eleanitzek hizkuntza batetik
bestera egiten dituzten transferentziak behatu eta analizatuko dira hizkuntzen arteko harremanak
aztertzeko. Ikerketa Lehen Hezkuntzako etapan zeuden 11 ikasle atzerritarrekin egin zen. Jasotako
emaitzetatik zera ondorioztatu da: laginean parte hartutako ikasleek aurretiaz zekizkiten hizkuntzetatik
lexikoa eta sintaxiarekin erlazionatutako transferentziak egin dituztela hizkuntza berria ikasterakoan.The influence of first and second language skills on third language acquisition (TLA) has been
analysed in different contexts in the last few years. Evidence from diverse research studies conclude
that language learners transfer linguistic resources to the target language. The aim of this paper is to
analyse the type of linguistic resources students transfer from one language to another when learning
a new language. Research was carried out with 11 immigrant students at primary school. Results from
the study show that language learners in our sample transfer previously acquired knowledge related
to lexicon and syntax, in order to learn a new language
Thermodiffusion in multicomponent n-alkane mixtures
Get PDFCompositional grading within a mixture has a strong impact on the evaluation of the pre-exploitation distribution of hydrocarbons in underground layers and sediments. Thermodiffusion, which leads to a partial diffusive separation of species in a mixture due to the geothermal gradient, is thought to play an important role in determining the distribution of species in a reservoir. However, despite recent progress, thermodiffusion is still difficult to measure and model in multicomponent mixtures. In this work, we report on experimental investigations of the thermodiffusion of multicomponent n-alkane mixtures at pressure above 30 MPa. The experiments have been conducted in space onboard the Shi Jian 10 spacecraft so as to isolate the studied phenomena from convection. For the two exploitable cells, containing a ternary liquid mixture and a condensate gas, measurements have shown that the lightest and heaviest species had a tendency to migrate, relatively to the rest of the species, to the hot and cold region, respectively. These trends have been confirmed by molecular dynamics simulations. The measured condensate gas data have been used to quantify the influence of thermodiffusion on the initial fluid distribution of an idealised one dimension reservoir. The results obtained indicate that thermodiffusion tends to noticeably counteract the influence of gravitational segregation on the vertical distribution of species, which could result in an unstable fluid column. This confirms that, in oil and gas reservoirs, the availability of thermodiffusion data for multicomponent mixtures is crucial for a correct evaluation of the initial state fluid distribution
40 urtean euskal gizartean eragiten Irakasle eskola - Humanitate eta Hezkuntza Zientzien Fakultatea (HUHEZI)
Get PDFEskuartean duzun liburu honetan argi ikus daitekeen bezala, 1976. urtean
Hezibideren eskutik, Irakasle Eskola sortu zenetik gaur egunera arte
oparoa izan da etxe honen emaria. Harrotasun eta poz handiz ikusiko
dute gaur, sorrerako hazia erein eta zaindu zuten haiek, nola hazi eta
edertu den jada 40 urte bete dituen proiektu itxaropentsu eta bitxi hau.
Mondragon Unibertsitatea ren baitan dagoen Humanitate eta Hezkuntza
Zientzien Fakultateak izaera berezia garatu du urteen joanean.
Unibertsitatea, Euskalduna eta Kooperatiboa dira proiektuaren oinarrizko
ezaugarria
Accurate drawbead modeling in stamping simulations
Get PDFAn adaptive line bead model that continually updates according to the changing conditions during the forming process has been developed. In these calculations, the adaptive line bead's geometry is treated as a 3D object where relevant phenomena like hardening curve, yield surface, through thickness stress effects and contact description are incorporated. The effectiveness of the adaptive drawbead model will be illustrated by an industrial example