Search

A low-computational-cost method is proposed in this paper to predict steady-state nonlinear aeroelastic response for high-aspect-ratio wings. This fast nonlinear static aeroelasticity method relies on a simple but robust mathematical approach. The work presented in this paper evaluates the accuracy of a nonlinear aerodynamic method on a large range of Mach numbers for a geometry representative of a typical industrial high-aspect-ratio-wing aircraft. The robustness of the method relies on the accurate estimation of the local pressure field based on an aerodynamic database using a local incidence estimated with a vortex lattice method. The database can be filled with flight test, wind tunnel test, or high-fidelity numerical simulation. The structural deformation is provided by a coupled aeroelastic high-fidelity numerical simulation, and so this paper focuses mainly on the development and validation of the aerodynamic model. Then, the flexible coefficients of the wing are compared to the high-fidelity aeroelastic numerical simulations for a set of Mach numbers ranging from subsonic to transonic conditions. The results presented in this paper show that the present method is very accurate for low-Mach-number regimes (error is lower than 1% on lift), and it is also adapted to transonic flow regimes because the error on lift is lower than 5%. For high Mach numbers, the current solution commits larger errors on drag and pitching moment coefficients.

International audience; A low-computational-cost method is proposed in this paper to predict steady-state nonlinear aeroelastic response for high-aspect-ratio wings. This fast nonlinear static aeroelasticity method relies on a simple but robust mathematical approach. The work presented in this paper evaluates the accuracy of a nonlinear aerodynamic method on a large range of Mach numbers for a geometry representative of a typical industrial high-aspect-ratio-wing aircraft. The robustness of the method relies on the accurate estimation of the local pressure field based on an aerodynamic database using a local incidence estimated with a vortex lattice method. The database can be filled with flight test, wind tunnel test, or high-fidelity numerical simulation. The structural deformation is provided by a coupled aeroelastic high-fidelity numerical simulation, and so this paper focuses mainly on the development and validation of the aerodynamic model. Then, the flexible coefficients of the wing are compared to the high-fidelity aeroelastic numerical simulations for a set of Mach numbers ranging from subsonic to transonic conditions. The results presented in this paper show that the present method is very accurate for low-Mach-number regimes (error is lower than 1% on lift), and it is also adapted to transonic flow regimes because the error on lift is lower than 5%. For high Mach numbers, the current solution commits larger errors on drag and pitching moment coefficients.

International audience; Aeroelasticity plays an important role in the design and certification of aircrafts. Whether steady aerodynamics is key for static methods, unsteady phenomenon is key for dynamic approaches. Nevertheless, in both aeroelastic problematics, it is basically aerodynamics who monopolizes the CPU cost. Thus, fast methods are interesting as alternative to the high cost of CFDCSM simulations.The aim of this study is to present an unsteady method that predicts the aerodynamics of aircrafts encountering a wind gust. First of all, the process that brought to the formulation of the static aeroelasticity from Wind Tunnel Tests (WTT) is refreshed. It is a rapid and robust method based on the principle of the local incidence shift due to flexible effects. This difference in the angle of attack is used to interpolate the pressure coefficient from aerodynamics lookup tables.Secondly, the static method (called Fast Nonlinear Static Aeroelasticity –FNSA–) is validated when analyzing a high aspect ratio wing which assures a flexible structure. The method deals with nonlinear, flexible and compressible effects in steady aerodynamics.Finally, an algorithm is proposed to integrate the FNSA formulation to the unsteady problem of gust load computation. The methodology uses a quasi-steady approach of the static solver together with Wagner delay function modeling the unsteadiness of the flow. Restricting our aeroelastic equation of motion to a simple mass-stiffness system, the airstream directed downward due to the gust is added to the downwash of each section. The formulation allows, then, a reaction to the gust at each time step that yields to flexible results with an accuracy comparable to the Unsteady Vortex Lattice Method but around 3600 times faster.

International audience

El treball presenta, de manera sintètica, els resultats dels treballs arqueològics realitzats en els darrers anys al Pirineu Oriental, especialment a la Cerdanya però també en altres comarques veïnes. Aquestes dades es combinen amb els principals estudis paleo-ambientals publicats. A partir d'aquí, els autors presenten una proposta d'interpretació històrica per al període VI-I ane., un model hipotètic que ofereixi un marc de referència que pugui ser validat o modificat per treballs futurs., The work presents, in a synthetic way, the results of the archaeological works carried out in the last years in the eastern Pyrenees, especially in Cerdanya, but also in other neighboring areas. These data are combined with the main published paleo-environmental studies. From here, the authors present a proposal for historical interpretation for the period VI-I B.C., A hypothetical model that offers a frame of reference that can be validated or modified by future works.

The application of the different parameters of the territorial transformations according to the determining factors for each one of the study periods through the Geographic Information Systems and the subsequent calculation of the exposure and the vulnerability of the floods has allowed to identify the flooding areas and the degree of damage. Also, assess the damage of the structures and contents affected by each of its uses, in accordance with the pre-established unitary prices by the different administrations. According to the experimental methodology used, it would start from damages quantified at €104 M today, which would double up to €202 M for B1 scenario/stage of 2050 and would reach maximum values of €268 M for the scenario A2 of 2050. The results obtained demonstrate the potential damages caused by the territorial transformations and amplified by the dynamics associated with the climate change. Therefore, it is necessary to take measures to minimize the risk and losses caused by floods. In this sense, it is proposed to organise the territory with the aim of making it more resilient and to reduce its exposure and vulnerability to the risk of floods. Urban planning must adapt to climate change and, especially, to the flood risk. At the same time, it is necessary to have local and municipal emergency plans for the basin, that include risk prevention and reduction measures, and establish warning systems for emergency managers and citizens themselves. L’aplicació dels diferents paràmetres de les transformacions territorials d’acord amb els condicionants per cadascun dels períodes d’estudi a través dels Sistemes d’Informació Geogràfica i el càlcul posterior de l’exposició i la vulnerabilitat de les inundacions han permès identificar les zones inundables i el grau d’afectació. També valorar els danys de les estructures i dels continguts afectats per cadascun dels seus usos, d’acord amb els preus unitaris preestablerts per diferents administracions. Segons la metodologia experimental emprada, es partiria d’uns danys quantificats en 104 M€ de l’actualitat, els quals es doblarien fins als 202 M€ per l’escenari 2050 B1, i s’assolirien uns valors màxims de 268 M€ per a l’escenari 2050 A2. Els resultats obtinguts posen en evidència els danys potencials causats per les transformacions territorials i amplificats per les dinàmiques associades al canvi climàtic. Així doncs, cal prendre mesures per minimitzar els risc i les pèrdues ocasionades per les inundacions. En aquest sentit, es proposa ordenar el territori amb l’objectiu de fer-lo més resilient i reduir la seva exposició i vulnerabilitat al risc d’inundacions. El planejament urbanístic s’ha d’adaptar al canvi climàtic i, en especial, al risc d’inundació. Paral·lelament, ens cal disposar de plans d’emergència locals i supramunicipals de conca que incloguin les mesures de prevenció i reducció del risc, i fixar sistemes d’alerta dels gestors d’emergència i de la pròpia ciutadania

L’objectiu del present treball és fer reflexió al voltant de la transformació de l’exèrcit japonès durant el feixisme Shôwa i les etapes anteriors. Per què l’exèrcit? Doncs perquè durant aquests períodes l’exèrcit va anar guanyant terreny a la política fins a convertir el país en una dictadura militar de facto l’any 1932. Ara bé, el control militar de la política i la societat té arrels molt profundes que es remunten fins més enllà de la Restauració Meiji. Des del poder l’Exèrcit va anar transformant el Japó en un règim militarista que va derivar en una expansió colonial sobre tot el Pacífic. És vital comprendre què va passar dins l’exèrcit per poder explicar fets ocorreguts durant l’expansió com la Violació de Nanjing o la Marxa sobre Baatan. Per poder estudiar la Guerra d’Àsia Pacífic cal veure tots els processos que van actuar dins de l’exèrcit: com els conflictes interns entre la Marina i l’Exèrcit de Terra, entre “l’Escola ordre” i “l’Estil imperial”. No són menys importants els maltractaments brutals que patien els soldats per part dels seus superiors, per no parlar del menyspreu a la vida que imperava en els alts comandaments de l’exèrcit. Aquests comportaments deriven en part d’una ideologia samurai i feudal que arrelava profundament a les ments dels militars. És vital entendre l’exèrcit perquè, de fet, és el principal actor polític i social del període. Això el converteix en el principal responsable de les atrocitats de l’època. Alguns historiadors occidentals que han tractat el període s’han deixat endur sovint per la singularitat de la figura de l’emperador dins la política japonesa. Tot oblidant-se que precisament per ser un símbol molt poderós, és utilitzat amb interessos per aquells qui ostenten el poder polític, econòmic i militar

Thesis submitted by Oriol Artime Vila to the Department of Physics of the Universitat de les Illes Balears for the degree of Doctor of Philosophy in Physics. Doctoral advisors: Dr. José J. Ramasco, Prof. Maxi San Miguel. Universitat de les Illes Balears, 2020., A system is considered complex when it is formed by a set of elements that interact in a simple way, and by virtue of these interactions, an emergent behavior appears. This means that the global behavior of a complex system cannot be neither explained nor deduced if the individual constituents are isolated and studied separately: the reductionism and the superposition principle, broadly used in physics, are no longer valid. Classical examples of this emergence are the origination of consciousness from neural interactions, the collapses in a financial market, or the synchronized motion of a flock of birds. The definition of a complex system is flexible, therefore, seemingly different systems can be studied under the same set of concepts, methods and techniques. This is the reason why their study has become a multidisciplinar and interdisciplinar challenge. Human societies are a paradigmatic example of a complex system, and it will be the one that we explore in this thesis. The constituents of this system are the individuals, or agents, that interact among them through different channels. We will focus on the collective phenomena of opinion dynamics and emergence of consensus, which are problems that have been traditionally tackled in sociology and psychology, but in the last years there have been valuable contributions coming from other scientific disciplines, such as physics, mathematics or computer science. These new viewpoints look for simple models that attempt to find the minimal conditions and the mechanisms that generate the phenomena that one wants to understand. The study of these minimal models usually analyzes either the type of mechanism that sustains the dynamics through which the individuals interact (opinion changes by imitation, social pressure of a majority, etc.) or the effects that the topology of the interactions (who interacts with whom) has on the model. However, a fundamental element that tends to be ignored is the temporal dimension. To offer a more detailed description of opinion dynamics, non-trivial statistical properties in the activity patterns of the agents, such as long-tailed interevent time distributions or memory effects, need to be included. By doing so, the description not only becomes more realistic, but, as we will see, the dynamical behavior of the models is radically different. The common element among all chapters is precisely the study of the origin and the impact of these temporal properties in the context of opinion dynamics. The first two chapters serve as introduction: the first one offers a general perspective of the type of problems that we will deal with and the tools to solve them, while the second one is a detailed description of the models that we will use and their properties. The first main block of the thesis contains three chapters, each of them corresponding to a publication. In the third and fourth chapter we investigate the mechanism of aging, understood as the influence that the time that an agent has been without changing state, the age, has on the next state change. We analyze the effects of this type of aging in the Kirman model, also known as the noisy voter model. By adding aging the system passes from a discontinuous finite-size phase transition to a continuous one, robust in the thermodynamic limit. We describe in detail, analytically and numerically, some properties of this new transition: critical point, universality class, stationary properties of the age of the agents. The role of aging in the standard voter model on multilayer networks will be also considered. We give a description of the model’s asymptotic states, such as a non-absorbing partially ordered one, in terms of the fraction of nodes participating simultaneously in the different layers, the topology of the networks and the time scales of the evolution of the models. In the last chapter of the first block, the fifth, we study how the distribution of arrival times to the absorbing state in the standard voter model and in the Susceptible-Infected (SI) model of epidemics is affected by different types of correlations. In this case, the correlations do not come from a modified dynamics, such as aging, but they are added manually so their strength is easily tunable. We show that positive temporal correlations in the interevent time activation speed up the dynamics, while topological correlations in the form of communities slow it down. When both types of correlations are considered together, the models show a high sensitivity to their relative strength, speeding up or slowing down the dynamics (with respect to the case without correlations) depending on their combination. The second main part of the thesis is formed by only one chapter, the sixth, where we study the first-passage time distributions for different opinion dynamics models. These probability distributions give the time that is needed to achieve for first time a state (for instance, the consensus) from a predetermined initial state (for instance, the state of exact coexistence of opinions). The main contribution of the chapter is the proof that the functional dependence of these distributions for the family of models described by the Fokker-Planck equation is determined uniquely by the initial and final states, and the eventual presence of absorbing states in the dynamics. We explain under which conditions we find either scale-free first-passage distributions, with their corresponding exponent, or single-peaked fast-decaying distributions. In this way, we overcome the limitation of the mean first-passage time, which is the most used quantity in this kind of problems, since it is unable to distinguish between these two very different behaviors. To complete the analysis, we verify the analytical predictions for models of different nature. To summarize, in this thesis we investigate opinion dynamics models through the lens of the statistical physics of collective phenomena. We put special emphasis on the temporal dimension. On the one hand, we study the behaviors that emerge from the modification of temporal interaction patterns among agents. On the other hand we analyze the first-passage time properties of different models, being able to classify their functionality in terms of few elements. Our results evince the need to include realistic temporal interaction statistics in the modeling, since their absence can lead to wrong or misleading conclusions.

En aquest treball analitzem la inscripció més rellevant d’una roca d’Oceja que va ser descoberta l'agost de 2017 en la que s'esmenten quatre personatges que s'identifiquen com qua-tuorvirs, amb tota seguretat els de Iulia Lybica (Llívia), a poc més de cinc km de la roca. Tres dels quatre magistrats i els quatre pares porten noms ibèrics: Bella per dues vegades, Adinildir, Gaisco, Bastobles, Betepe[-] i Erdoild[ir], i només un dels magistrats, Corneli(us), porta un nom llatí. Aquesta circumstància ens mostra simultàniament que les elits ceretanes de Iulia Lybica havien perpetuat el seu control de la ciutat ja romanitzada, i que aquesta inscripció pertany al primer moment de la romanització, de manera que és plausible considerar que aquesta fos una de les primeres generacions de magistrats del municipi Iulia Lybica. Aquest fet confirma epigràfi-cament el que ja se sospitava per les referències de les fonts clàssiques i la documentació arqueològica d'un fòrum a Llívia i reforça la hipòtesi que Iulia Lybica fos un municipi de funda-ció augustal, coincidint així amb les dades arqueològiques., Dans cet article, nous analysons l'inscription la plus pertinente d'une roche d’Osséja, découverte en août 2017, dans laquelle quatre personnages sont identifiés comme quatuorvirs, avec certitude ceux de Iulia Lybica (Llívia), à un peu plus de cinq kilomètres du rocher. Trois des quatre magistrats et quatre parents ont des noms ibériques : Bella deux fois, Adinildir, Gaisco, Bastobles, Betepe[-] et Erdoild[ir], et un seul des magistrats, Corneli(us), a un nom latin. Cette circonstance montre simultanément que les élites céretanes de Iulia Lybica ont perpétué leur con-trôle de la ville déjà romanisée, et que cette inscription appartient à la première période de roma-nisation, il est donc plausible de considérer qu'il s'agit de l'une des premières générations de ma-gistrats de la commune Iulia Lybica. Ce fait confirme épigraphiquement ce qui était déjà suspecté par des références aux sources classiques et à la documentation archéologique d'un forum à Llívia, et renforce l'hypothèse selon laquelle Iulia Lybica était une municipalité de fondation au-gustale, coïncidant ainsi avec des données archéologiques.

[EN] We consider the herding-to-non-herding transition caused by idiosyncratic choices or imperfect imitation in the context of the Kirman Model for financial markets, or equivalently the Noisy Voter Model for opinion formation. In these original models, this is a finite-size transition that disappears for a large number of agents. We show how the introduction of two different mechanisms makes this transition robust and well defined. A first mechanism is nonlinear interactions among agents taking into account the nonlinear effect of local majorities. The second one is aging, so that the longer an agent has been in a given state the more reluctant she becomes to change state., [FR] Nous considérons la transition grégaire/non grégaire causée par des choix idiosyncrasiques ou une imitation imparfaite dans le contexte du modèle de Kirman pour les marchés financiers ou, de façon équivalente, du modèle de l'électeur aléatoire pour la formation de l'opinion. Dans ces modèles originaux, il s'agit d'une transition de taille finie qui disparaît pour un grand nombre d'agents. Nous montrons comment l'introduction de deux mécanismes différents rend cette transition robuste et bien définie. Un premier mécanisme est celui des interactions non linéaires entre agents tenant compte de l'effet non linéaire des majorités locales. La deuxième est le vieillissement, de sorte que plus un agent a été longtemps dans un état donné, plus il devient réticent à changer d'état., Partial financial support has been received from the Agencia Estatal de Investigacion (AEI, Spain) and Fondo Europeo de Desarrollo Regional under the Project PACSS, Project No. RTI2018-093732-B-C2 (AEI/FEDER, UE) and the Spanish State Research Agency, through the Maria de Maeztu Program for units of Excellence in R&D (MDM-2017-0711). A.F.P. acknowledges support by the Formacion de Profesorado Universitario (FPU14/00554) program of Ministerio de Educacion, Cultura y Deportes (MECD) (Spain).

Con autorización de la editorial para este capítulo., [EN] This paper offers new information about metallurgical activities in the site of Castellot de Bolvir (Cerdanya) during the 2nd-1st century BC. A singular building with several rooms was identifyed as a metallurgical workshop, where some pottery vessels were also identified as crucibles. The sediment from this crucible was studied by Scaning Electron Microprobe (SEM). Some minerals and metallic particles have been identified, defining a polymetallic workshop (iron, copper, brass and lead) including noble metals (gold and silver) and cinnabar., [ES] Se presentan datos sobre la actividad metalúrgica en el poblado de Castellot de Bolvir (Cerdanya) durante su fase de ocupación en los siglos II-I a.C. La identificación de un edificio con varias estancias donde se realizaron diferentes actividades vinculadas con la metalurgia y algunos elementos cerámicos que podrían interpretarse como crisoles, llevó a indagar sobre su funcionalidad a través del estudio de los sedimentos con Microscopia Electrónica de Barrido (MEB). La identificación de diferentes partículas metálicas y minerales permite ampliar la información sobre los metales procesados en este taller principalmente, definiendo un área de actividad polimetálica (hierro, cobre, plomo, latón) y destaca la presencia de metales nobles (oro y plata) y cinabrio., Esta investigación ha contado con la ayuda del proyecto MINECO, HAR2013-41629-P, Paisajes de la Hispania romana: de la diversidad a la complementariedad, y del Proyecto de la Generalitat de Catalunya, PATCA, 2014/100875.

In Western Europe, the transition from the middle Iron Age to the early Roman period implied changes in livestock practices, with the emergence of a specialized and selective animal husbandry. These changes have been related in Italy and south of France with changes in livestock management involving their mobility between ecologically complementary areas. The study of this question in the Iberian Peninsula has only been partially investigated through palaeoenvironmental analyses, and the information about the origin and significance of this phenomenon is very scarce. To shed new light on this topic we used an archaeozoological approach, with the application of geometric morphometrics. They were used to study size and shape variability in sheep astragali from 9 sites dating from the middle Iron Age to the early Roman period (5th c. BC–3rd c. AD) and located on the Pyrenees and on the north-eastern Iberian coast as a case study. The results we obtained, combined with Number of Identified Specimens (NISP) and kill-off patterns, showed local specificities in terms of breeding methods and sheep morphologies between the two areas during the middle Iron Age. On the contrary, sheep with similar size and the implementation and development of similar sheep husbandry practices in the Pyrenees and the north-eastern Iberian coast were documented during the early Roman period. These results suggest the existence of livestock links between these two areas during the Roman period, that could be involved a possible movement of sheep between the lowlands and the Pyrenees for the first time.

Olesti i Vila Oriol. ¡Al basurero!: el tratamiento del cuerpo del esclavo romano y tardo-romano en algunos yacimientos rurales del N.E. Peninsular. In: Praxis e Ideologías de la Violencia. Para una anatomía de las sociedades patriarcales esclavistas desde la Antigüedad. XXXVIII Coloquio del GIREA.

"Old and New Territorial Dependencies : New Data about the Ager per extremitatem mensura comprehensus in the Ars Gromatica Gisemundi". The recent edition of the Ars Gromatica siue Geometria Gisemundi, which is based on two manuscripts that date from the ninth century (mostly ACA Ripoll 106), has offered new data about the literature of the Roman land surveyors. The work includes a description of the division of Spain’ s provinces in late Roman times (Discriptio Hispaniae), especially focused on the Carthaginensis region. The author based his text on several unpublished ancient sources dating from the early empire to the byzantine period. The text mentions some land surveying activities and describes some specific works in order to delimitate territories that allow us to propose the existence of a type of provincial land surveying documentation that has remained unknown until now. In addition, the document provides new information about the Byzantine presence in Spania and the possible boundaries of their occupation., La reciente edición del texto del Ars Gromatica siue Geometria Gisemundi procedente de dos manuscritos del siglo ix (especialmente ACA Ripoll 106) ha proporcionado nuevos datos sobre la literatura de los agrimensores romanos. En esta obra se ha conservado una descripción de la división provincial de la Hispania tardoantigua (Discriptio Hispaniae) focalizada en la Carthaginiensis, que el autor basó en diversas fuentes inéditas de época antigua, tanto de época imperial como bizantina. La mención en el texto a diversas fases de actividad agrimensoria, con precisas descripciones de trabajos de delimitación territorial, permite proponer la existencia de una documentación provincial gromática, hasta el momento desconocida, de gran interés histórico. A su vez, el documento ofrece nueva información sobre la presencia bizantina en Spania y los posibles límites territoriales de su ocupación., Olesti i Vila Oriol, Andreu Expósito Ricard. Viejas y nuevas dependencias territoriales. Nuevos datos sobre elAger per extremitatem mensura comprehensus en la Ars Gromatica Gisemundi. In: Lo viejo y lo nuevo en las sociedades antiguas: homenaje a Alberto Prieto.

Aquest article té com a objectiu presentar el jaciment del Tossal de Baltarga (Bellver de Cerdanya, Lleida), un assentament situat en un turó controlant els accessos a la vall de la Cerdanya i amb una ocupació entre els segles iv i i aC. Amb una funció com a punt de guaita i de control del territori, les seves característiques i la seva evolució històrica ofereixen un magnífic exemple per comprendre l’estructuració territorial del poble ceretà durant l’Antiguitat. A la vegada, es tracta d’un dels millors casos documentats per a poder interpretar la participació d’aquesta regió en els diferents fets històrics del període, especialment en relació amb l’arribada i conquesta per part de Roma. The objective of this paper is to present the site of Tossal de Baltarga (Bellver de Cerdanya, Lleida), a settlement spanning the 4th to the 1st century BC perched in a hill controlling the accesses to the Cerdanya Valley. The site’s main function was to monitor and control the territory and its resources. The site’s historical evolution offers a good example in the understanding of the territorial structure of the Cerretani tribe during Antiquity. The site is likewise serves as one of the best cases to analyse the region’s role in the historical framework, especially during the advance and conquest of the region by Rome.

In recent times new research has completed our vision about the development of the urban system in northeast Hispania, identifying several stages: from the earliest proto-urban settlements of 2nd c. BC. until the eclosion of consolidated cities in the 1st half of 1st c. BC. This process is analyzed in its dual identity, urbs and ager. Nuevos trabajos han permitido en los últimos años completar nuestra visión sobre el desarrollo del fenómeno urbano en el Noreste peninsular, identificando la existencia de diversas fases de urbanización, desde los primeros establecimientos protourbanos del s. II a.C. hasta la eclosión de las definitivas ciudades en la primera mitad del s. I a.C. Se analiza este proceso en su doble vertiente: urbs y ager.