Metabolic emergent auditory effects by means of physical particle modeling : the example of musical sand

International audienceIn the context of Computer Music, physical modeling is usually dedicated to the modeling of sound sources or physical instruments. This paper presents an innovative use of physical modeling in order to model and synthesize complex auditory effects such as collective acoustic phenomena producing metabolic emergent auditory organizations. As a case study, we chose the "dune effect", which in open nature leads both to visual and auditory effects. The article introduces two particle physical models, able to collaborate. The first is dedicated the synthesis of spatial (or visual) dynamics effects of moving sand dunes. The second is dedicated to the rendering of acoustical dynamics of "sounding sands". Altogether, they lead to a multisensorial simulation of sand in dune

Describing/Modelling the Dynamics of Pedestrian Behaviour: From the Role of Ambiance to a Hypothesis for a Physical Model

Let us look a little closely at the movement of people in public space. What do we see if we follow their paths, the relations played out among them, the areas occupied or left empty and, more importantly, the dynamics of these constant variations and adjustments? In designing public space, it is increasingly important to look at potential movement. This is the case whether considering the quality and diversity of itineraries (e.g. through parks, museums, stadiums, squares) or for the ease with which the public can get in to or out of a given place (e.g. shopping centres and railway stations). We must therefore seek to understand both the individual and collective dynamics involved here and bring to bear analysis and design tools that take them into account. Pedestrian behaviour in public space is a vast subject of research, involving numerous disciplines. This article will address it from the point of view of path making. The approach developed here highlights the role played by architectural and urban surroundings (Jean-François Augoyard 1979) in pedestrian dynamics, as situations of sensory interaction, which we experience according to a network-actor system (Bruno Latour, 2006). The actor may be a physical person, a group of persons, a moveable or fixed built object or semiographic features within the space, sensory elements of the environment such as a particular light, a zone or source of heat or coolness, soothing or stress-inducing sounds, and so on. We will first present the adaptation of a method of observation in situ (recurrent observation, (Pascal Amphoux, 2001), then describe experiments with a numerical relational model. This is the physical model developed by ACROE, which generates dynamics using the descriptors and operators of Newtonian physics (the force concept and the principle of action-reaction). The initial subject of study is an element of public architecture that is particularly dynamic, namely the automatic double doors at the entrance to a shopping centre. Since this first study (Tixier, 2000 ), numerous applications of this model have been developed and have enabled an approach to the whole of urban configurations having to do with public space to take place with a view to analysing existing spaces and investigating spatial design. This is covered in the third section of this article

Formal Modulation for Acoustic Performances of a Bridge

In the last fifteen years in architecture the frequent use of design instruments such as algorithms, dynamical relations, parametric systems, mapping, morphogenesis, cellular automata and bifurcation with broken symmetry shows clearly how contemporary thinking in mathematics and physical sciences, dealing with complex dynamics, non-linear systems, chaos, emergent properties, resilience, etc., has changed the way we think about design and the life of today's cities

An inside look at Bogotá’s urban renewal from broad urban stories to everyday tales

The Colombian capital has become recently a model of urban development thanks to a successful process of urban renewal that fostered the insertion of the city in the international scene. In order to understand the complexity of Bogotá’s transformation, it is essential to examine the objective causes that have determined the changes and the discourses that have shaped it. An analysis of the most important facts of Bogotá’s transformation, of the image of the city promoted by the discourses of the experts and of the narratives created by the residents, permits to better understand the process globally. In addition, confronted with the observation of new emerging dynamics in renovated areas, this body of knowledge permits to recognize situated controversies and bring out certain lessons about urban project management that can be learned from the case of Bogotá.Peer Reviewe

Paysages réactionnaires : petit essai contre la nostalgie de la nature (sous la dir. de Federico Ferrari)

Ce petit essai, qui prend le contre-pied de la pratique aménagiste actuelle, en contient en fait deux, au moins. Deux car l’auteur principal, Federico Ferrari, architecte et chercheur, a invité Marco Assennato, philosophe, à contribuer par un texte placé en fin d’ouvrage. Au moins deux, car le développement proposé par Federico Ferrari passe tour à tour de la critique architecturale, à une histoire du paysage, puis à une approche politique de la fabrique actuelle du territoire par un certain ..

Penser depuis la frontière : expérimentations méthodologiques et épistémologiques entre art et sciences humaines

Suivre les morts, pousser les portes d’un hôtel de ville, construire une plate-forme multimédia, déployer des actions artistiques et sociales, autant d’expériences auxquelles nous invitent les auteures de cet ouvrage qui se propose de Penser depuis la frontière. Six auteures, Anne Bossé, Christiane Carlut, Emmanuelle Chérel, Amélie Nicolas, Elisabeth Pasquier et Véronique Terrier-Hermann, chercheuses ou artistes, croisent leurs travaux. Elles nous font entrer directement dans la fabrique de l..

L’eau dans les paysages de l’énergie

Les résultats présentés dans cet article sont issus d’une recherche interdisciplinaire portant sur les enjeux énergétiques et les ressources environnementales d’un quartier construit sur une presqu’île, celle de Grenoble. Sur ce site, les dispositifs énergétiques liés à l’eau permettent de collecter, de convertir et/ou de distribuer énergie et flux de l’eau. Nous proposons d’aborder la diversité de ces devenirs de l’eau à travers deux notions, celle des nœuds socioénergétiques aux croisements des grands réseaux et des énergies renouvelables et celle des interfaces entre le milieu aquifère et son environnement atmosphérique et terrestre contigu. Pour croiser ces deux approches, nous utilisons des représentations en transect afin de révéler ce paysage mi-sociotechnique, mi-géographique, et pour que soient débattues autrement dans des espaces de décision collective les relations entre ressources naturelles, exploitations énergétiques et paysages de l’eau.The findings presented in this article are the fruit of interdisciplinary research on the energy and environmental resource challenges of an urban development project on the Grenoble Peninsula. On this site, water-related energy systems are used to collect, convert and/or distribute energy and water. We propose to address the diversity of these future water resources through two concepts. One of these concepts is that of a socio-energetic node at the intersection of major networks and sources of renewable energy and the other is that of the interfaces between the aquifer and its atmospheric and terrestrial environments. Transect representations are used to reveal this semi-sociotechnical, semi-geographical landscape in order to compare the two approaches and to organise a process of collective debate and decision-making on the interrelations between natural resources, energy uses and water landscapes

Evaluation of streamwater composition changes in the Vosges Mountains (NE France): 1955–2005

n 1995, in the southwestern Vosges Mountains (NE France), 158 of 395 streams (40%) had a pH lower than 5.5 at baseflow. As elsewhere in Europe, acid deposition has decreased since the seventies, as has base cation deposition. In order to assess the response of streamwater to decreasing deposition, we compared their present chemical composition to their former composition. All comparisons showed a decrease in sulphate concentration, which was greater on granite than on sandstone. In addition calcium, magnesium and aluminium concentrations generally decreased. Acidity in streams draining granite decreased in spring, especially during the eighties, decreases were not observed on sandstone. Continuous monitoring of 5 streams since 1998 confirmed that Al concentrations decreased while changes in pH were small. Chemical trends in streams from the Vosges massif fell between those measured in Northern Europe and Central Europe. This study provides the first broad-scale overview of surface water acidification and recovery in France and emphasizes the need for continuous monitoring to assess long-term changes in aquatic ecosystems

Conduites en milieu urbain. Analyse in situ et expérimentation virtuelle

International audienceCette recherche se situe dans le cadre des ambiances architecturales et urbaines. Elle propose de tester des modèles morphodynamiques (en particulier les modèles physiques développés par l'Acroe) générant des représentations par synthèse numérique de phénomènes sensibles. Une confrontation avec l'observation in situ de ces phénomènes et les représentations sonores et visuelles issues de la synthèse est ainsi rendu possible. Ce retour par l'expérimentation virtuelle à l'observation et à la catégorisation phénoménale à partir de causes potentielles inférées au modèle permet d'envisager une utilisation du modèle physique comme outil de re-construction d'effets et par là même à la conception. L'exemple développé ici sera celui des dynamiques de conduites piétonnières qui s'inscrivent de façon récurrente dans l'espace public urbain

Retour vers le futur

Et si l’espace des mobilités du Paris des années 1920 avait déjà des attributs et des qualités que nous recherchons et projetons aujourd’hui pour les espaces métropolitains de demain ? À savoir, un foisonnement des mobilités et des usages au fil de la Seine et des canaux, une voirie partagée ou se croisent piétons, vélos et véhicules sans délimitation stricte au sol, des moyens de locomotion variés et inventifs tant dans leur forme, leur fonction que leur mode de propulsion, la marche urbaine omniprésente et peu canalisée, et même la présence d’ani­maux à chaque coin de rue. Les mobilités participent du façonnement du paysage. Lorsqu’elles disparaissent, elles laissent presque toujours des traces. Cette situation peut être donnée à voir à notre regard d’aujourd’hui grâce aux rares et magnifiques plans cinématographiques réalisés par André Sauvage en 1928 dans Études sur Paris. Retour vers le futur. Serait-il possible d’utiliser avantageusement des documents à caractère historique dans des situations où il est avant tout question de changements à venir ?Do the mobilities of Paris in the 1920’s resemble or presage those that urban planners and designers seek today for the future of metropolitan areas? That period offered a richness of means of movement and of corresponding expe­riences and uses, be it in and alongside the Seine or through the coexistence of a diversity of possibilities for movement-walking, pedaling or motoring-in a common, undifferentiated street space. It associated innovation in the form, use and mechanical design of means of loco­motion with great freedom of movement for those on foot and a rich presence of animal life. Ali mobilities play a raie in the shaping of the urban landscape and those that disappear tend to leave traces. Back to the future. The rare, exceptionally fine cinematic images realized by André Sauvage’s 1928 film Études sur Paris suggest the possibility of considering historical documents as source of ideas for reactivating and redefining the latent qualities of the spaces they portray