18 research outputs found

    Nanotermodinamika

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    This work presents a theory that goes beyond the scope of Classical Thermodynamics. It is named Nanothermodynamics, and it was created and developed by physicist Terrell Hill in the 1960s. In essence, it includes the necessary tools for the study of small systems, by means of a thermodynamic potential known as the subdivision potential. In fact, it enables the construction of the "nanocanonical" statistical ensemble, by introducing a distinctive degree of freedom related to its distribution of small systems. Through examples, we shall emphasize the importance of taking account of finite size effects in the nanothermodynamic region. With that being said, undergraduates taking a course on Thermodynamics and Statistical Mechanics will find it rewarding to understand and internalize the fundamentals of Nanothermodynamics. Even if it has remained abandoned and left aside for many years, Hill’s theory has nowadays proved useful to scientists of wide-ranging areas for the advancement of their research, such as in Chemical Physics and Biology.; Lan honetan, Termodinamika Klasikotik haratago doan teoria aurkeztuko dugu: Terrell Hill fisikariak 1960ko hamarkadan sortutako eta garatutako Nanotermodinamika. Funtsean, sistema txikien azterketarako nahitaezkoa den tresneria biltzen du, banatze-potentzial deritzon potentzial termodinamikoa dela medio. Hain zuzen, horrek ahalbidetzen du, besteak beste, banatzearekin lotutako askatasun-gradu berezia abian jartzeaz bat, multzo estatistiko nanokanonikoaren eraikuntza. Adibideen bidez, eskualde nanotermodinamikoan kasuan kasuko tamaina finituko efektuek duten esanguran sakonduko dugu. Horiek horrela, Termodinamika eta Fisika Estatistikoa irakasgaiko ikasleei arras aberasgarria gertatuko zaie, alde batetik, ohiko Termodina- mikaren irismenaz ohartzea, eta, bestetik, Nanotermodinamikaren nondik norakoak ulertzea eta barneratzea. Aipatzekoa da ezen urte luzez baztertuta egon bada ere, egun Hill-en teoria baliagarria gertatu zaiela hainbat esparrutako zientzialariei; esate baterako, kimika fisikoan eta biologian

    MinervaLab: Jupyter Notebook-etan oinarritutako irakaskuntza-proiektu alternatiboa

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    Technologies and platforms developed during the last years offer several ways to implement interactivity-based educational projects and to create and publish educational material. The MinervaLab project, which is based in software development tools and workflows, contains interactive material aimed to teach Thermodynamics. Applications, their documentation and theoretical explanations are available for both students and developers (the project can be consulted in https://minervalab.readthedocs.io). An experimental group consisted of students has shown interest on the project and highlighted its usefulness.In the future, MinervaLab will be used to teach phase transitions and van der Waals mechanical equation of state.; Azken urtetan agertutako teknologia eta plataforma berriek ikasleen elkarrekintzan oinarritutako proiektuak garatzeko eta irakaskuntzarako beharrezkoa den materiala sortzeko eta hedatzeko bide ugari eskaintzen dute. MinervaLab proiektuak Jupyter Notebook plataforman eta softwarearen garapenean erabili ohi diren tresna eta lan-fluxuetan oinarritutako Termodinamikaren inguruko material interaktiboa jasotzen du. Garatutako aplikazioak dokumentatuta eta azalpen teorikoz lagunduta aurkezten dira, material guztia ikasle zein garatzaileentzat eskuragarri ipiniz (proiektu guztia https://minervalab.readthedocs.io helbidean kontsulta daiteke). Egindako lanarekiko interes handia azaldu eta eskola emateko erabilgarria dela azpimarratu du ikaslez osatutako talde esperimentalak. Etorkizunean, MinervaLab proiektua fase-trantsizioen eta van der Waals-en egoera-ekuazio mekanikoaren inguruko eskolak emateko erabiliko da

    Oinezkoen simulazioak giza indarraren ereduaren bidez: larrialdi-egoerak

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    Pedestrian areas such as underground stations or shopping centres are more often than not overcrowded. In case of emergency, the safety of pedestrians is called into question. As a matter of fact, the analysis of pedestrian flows is highly meaningful. This study is developed following the Social Force Model, a perspective on modelling of crowd dynamics and pedestrian motion. The mathematical formulation, fields of applications, limits and the relation with experimental data have been considered. Moreover, a simulated evacuation of a single-exit room has been analysed, together with the influence of obstacles in the event of an emergency evacuation procedure. It has been proven that placing a wall or a column with special features can help reducing the evacuation time because the obstacles tend to organize the flow. In addition replacing a long wall by a row of columns or small walls can even improve the results.; Oinezkoentzako inguruneetan, metroetako pasabideetan edo merkataritza-guneetan esaterako, jende ugari pilatzen da. Ibiltarien segurtasuna arriskuan ipintzen du horrek, bereziki larrialdi-egoeretan. Ondorioz, oinezkoen dinamika aztertzeak berebiziko garrantzia dauka. Lan honetan jendetzaren dinamika modelizatzen duen ereduetako bat landu da, giza indarraren eredua alegia. Besteak beste, eredu horren formulazio matematikoa, aplikagarritasun-esparruak, mugak eta datu esperimentalekiko erlazioa aztertu dira. Gainera, eredu horren bitartez irteera bakarreko gela baten ebakuazioa aztertu da, ibiltarien hustutze prozesuan oztopoek nola eragiten duten ikusteko. Ate ondoan ezaugarri bereziak dituen horma edo zutabe bat kokatzeak irtete-denbora murrizten duela egiaztatu da, oztopoek oinezkoen fluxua ordenatzen dutelako. Bestalde, horma luze baten ordez zutabeen edo horma txikien ilara bat eratu daiteke emaitzak are gehiago hobetzeko

    Prozesu estokastikoak fisikan eta ekonomian: higidura browndarretik finantza-merkatuen ereduetara

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    rket behaviour. In fact, the universality of some simple statistical characteristics in the markets is noticeable: several financial variables (such as the probability distributions of stock returns) show scale invariance. These scale-free phenomena are relevant to different areas of physics.Thus, for physicists, economic research has become the study of a wealth of data on a well-defined complex system. One of the most important analysis methodologies is based on the use of stochastic processes. In fact, in the case of some complex physical systems with universal characteristics, deterministic models are not useful. From the parallelism between both areas, therefore, it would be fair to introduce the stochastic approach in the economic field and thus, model a stochastic market. In other words, it is possible to create independently a physical model and an economic model, using the same mathematical concept.; Azken hamarkadetan, ikerkuntza-talde anitzek, fisikan garatutako metodoak erabili dituzte merkatuen portaera aztertzeko. Izan ere, merkatuetako ezaugarri estatistiko sinple batzuen unibertsaltasuna nabarmena da: eskala-menpekotasunik gabeko fenomenoak antzeman daitezke (itzulkinen probabilitate-banaketetan, adibidez), fisikako hainbat esparrutan agertzen diren gisan. Hala, fisikarientzat, ekonomia ikertzea, ongi definitutako sistema konplexu bati buruzko datu ugari aztertzea bilakatu da. Aztertze-metodologia garrantzitsuenetariko bat, adibidez, prozesu estokastikoak erabiltzean datza. Izan ere, fisikan, ezaugarri unibertsalak dituzten sistema konplexu batzuen kasuan, eredu deterministak ez dira baliagarriak. Bi esparruen arteko paralelismotik, hortaz, ikuspegi estokastikoa ekonomiaren esparruan sartzea, eta merkatu estokastiko bat ereduztatzea zilegi litzateke. Hau da, kontzeptu matematiko beraz baliatuz, posible da eredu fisiko eta ekonomiko bat independenteki sortzea

    Analysis of future teacher’s aptitude for solving science problems related to everyday life

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    [Es]En este trabajo se aborda la problemática detectada como consecuencia del fracaso que presenta gran mayoría del alumnado de la E. U. de Magisterio de Bilbao, futuro profesorado de Educación Primaria (EP), en la aplicación creativa de conocimientos transmitidos en el aula de ciencias, esto es, en la resolución de problemas y en la explicación de fenómenos cotidianos del mundo que nos rodea. Para ello se ha analizado, por un lado, su capacitación en relación a varios tópicos de ciencias incluidos en el Área de Conocimiento del Medio en la EP, presentados en un contexto de ciencia en la vida cotidiana y su autovaloración en relación a su capacitación didáctica para abordarlos en aulas de ciencias escolares y, por otro, la metodología didáctica utilizada en las clases de ciencias que han recibido en etapas educativas previas a la universitaria.[En]This paper addresses the problems detected as a result of failure that presents vast majority of pupils of the E. U. de Magisterio de Bilbao, future teachers of Elementary Education (EE), in the creative application of knowledge transmitted in the science classroom, that is, in the resolution of problems and the explanation of everyday phenomena of the world that surrounds us. To this aim, these three aspects have been analysed: their aptitude in relation to several topics of science included in the “Area de Conocimiento del Medio” in EE, presented in a context of science in everyday life, their self-evaluation of their science teaching qualification to approach them in science school and science teaching methodology used in their science classes in stages prior to the university

    Larmor-en prezesioa kristaletan gertatzen diren aldaketen detektagailu

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    Material batean gertatzen diren trantsizio magnetikoen eta haren egitura kristalinoaren arteko erlazioa aztertzea oso garrantzitsua da, batik bat multiferroikoak diren materialetan. Gehienetan, trantsizio magnetikoetan gertatzen diren egiturazko al-daketak gako dira trantsizioan agertzen edo desagertzen den polarizazio elektrikoaren jatorria zein den ulertzeko. Hala ere, hainbat materialetan aldaketa horiek oso txikiak dira eta horiek detektatzea oso zaila izan daiteke. Hori da aztergai dugun materialean (MnWO4) gertatzen dena. Hori dela eta, ondorio zuzenetara heltzekotan, ezinbestekoa da kristalaren egitura ikertzeko teknika oso sentikorrak erabiltzea. Egiturazko aldaketa oso txikiak aztertzeko neutroien prezesioaz baliatzen den teknika aurkeztuko dugu lan honetan, neutroien bidezko Larmor-en difrakzioa, hain zuzen ere. Nahiz eta lortutako emaitzak behin-behinekoak izan, oso argi ikusten dira zein diren teknika honen indarra eta potentzia, eta trantsizio magnetikoetan gertatzen diren egiturazko aldaketak; The study of the interplay between magnetic transitions and the crystal structure is crucial for the investigation of multiferroic materials. In fact, the structural changes across the magnetic transitions are usually the clue to ascribe the origin of the concomitant appearance of electric polarization. Nevertheless, in some materials, those structural variations are so small that their detection is very difficult. That is the case of MnWO4. Hence, in order to reach appropiate conclusions we need to use experimental techniques which are very sensitive to crystal structure variations. In this piece of work we present an experimental technique that takes profit of the precession of the neutrons in magnetic fields in order to see those small changes in the crystallographic structures, that is, the Larmor diffraction by means of neutrons. Even if the obtained results are rather preliminary, the undoubtedly show the strength and power of this technique and the modifications of the structure across the magnetic transitions

    Bateria-multzoen simulazio elektrotermikoak: 14S5P bateria-multzo komertziala

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    Electrothermal behaviour of 14S5P battery-pack, usually placed in small electric vehicles, is analysed for the first time using multiphysics simulations. An electrochemical model is developed to describe the electric behaviour of LMO 26650 battery (3.5 Ah). NMC active material is added in the LMO cathode (0, 29, and 59 % wt) to check the improvement of the electrical performance of the battery. The heating process of LMO 26650 battery is simulated in a high intensity discharge process (10 A). As a result, the temperature of the cell suffers an important increment of 64 %. Finally, with intensities of usual working conditions, the temperature of 14S5P battery-pack does not increase remarkably.; Normalean ibilgailu elektriko txikietan erabiltzen den 14S5P bateria-multzoaren jokaera elektrotermikoa lehenengo aldiz aztertu dugu simulazio multifisikoen bidez. LMO kimikako 26650 bateriaren (3,5 Ah) jokaera elektrikoa simulatzeko eredu elektrokimikoa garatu dugu. LMOko katodoan NMC material aktiboa gehitu dugu (pisuan, % 0, % 29 eta % 59), bateriaren ezaugarri elektrikoak hobetzen direla egiaztatzeko. LMO kimikadun 26650 bateriaren beroketa simulatu dugu intentsitate altuko deskarga batean (10 A), eta tenperatura % 64 igotzen dela behatu dugu. Azkenik, ohiko lan-baldintzetako korronteetan, 14S5P bateria-multzoaren tenperatura ez dela era nabarmenean handitzen frogatu dugu

    Analysis of future teacher’s aptitude for solving science problems related to everyday life

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    [Es]En este trabajo se aborda la problemática detectada como consecuencia del fracaso que presenta gran mayoría del alumnado de la E. U. de Magisterio de Bilbao, futuro profesorado de Educación Primaria (EP), en la aplicación creativa de conocimientos transmitidos en el aula de ciencias, esto es, en la resolución de problemas y en la explicación de fenómenos cotidianos del mundo que nos rodea. Para ello se ha analizado, por un lado, su capacitación en relación a varios tópicos de ciencias incluidos en el Área de Conocimiento del Medio en la EP, presentados en un contexto de ciencia en la vida cotidiana y su autovaloración en relación a su capacitación didáctica para abordarlos en aulas de ciencias escolares y, por otro, la metodología didáctica utilizada en las clases de ciencias que han recibido en etapas educativas previas a la universitaria.[En]This paper addresses the problems detected as a result of failure that presents vast majority of pupils of the E. U. de Magisterio de Bilbao, future teachers of Elementary Education (EE), in the creative application of knowledge transmitted in the science classroom, that is, in the resolution of problems and the explanation of everyday phenomena of the world that surrounds us. To this aim, these three aspects have been analysed: their aptitude in relation to several topics of science included in the “Area de Conocimiento del Medio” in EE, presented in a context of science in everyday life, their self-evaluation of their science teaching qualification to approach them in science school and science teaching methodology used in their science classes in stages prior to the university
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