Visual Representation in GENESIS as a tool for Physical Modeling, Sound Synthesis and Musical Composition

International audienceThe motivation of this paper is to highlight the importance of visual representations for artists when modeling and simulating mass-interaction physical networks in the context of sound synthesis and musical composition.GENESIS is a musician-oriented software environment for sound synthesis and musical composition. However, despite this orientation, a substantial amount of effort has been put into building a rich variety of tools based on static or dynamic visual representations of models and of abstractions of their properties. After a quick survey of these tools, we will illustrate the significant role they play in the creative process involved when going from a musical idea and exploration to the production of a complete musical piece. To that aim, our analysis will rely on the work and practice of several artists having used GENESIS in various ways

Evaluation de la chaine numérique en fabrication par Electron Beam Melting

National audience— Les dernières améliorations des procédés de fabrication additive, et entre autre la possibilité de produire des pièces métalliques, a permis d'étendre l'utilisation de ces procédés, réservés jusque-là au prototypage, à la production de pièces fonctionnelles. Ces nouveaux champs d'application ont mis en évidence les nombreuses lacunes des différentes étapes numériques de mise en production de la pièce. L'ensemble de ces étapes est rassemblé sous l'appellation : chaine numérique. Cet article s'attachera à analyser la chaine numérique actuelle afin de déterminer les changements qui doivent être apportés afin de l'améliorer. Fort de ces axes d'amélioration et de l'expérience acquise depuis de nombreuses années dans la chaine numérique pour les procédés soustractifs, une proposition d'environnement de Fabrication Assisté par Ordinateur (FAO) dédié au procédé EBM sera présentée. Mots-clés— Electron Beam Melting (EBM) ; Fabrication Assistée par Ordinateur (FAO) ; chaine numérique ; Fabrication additiv

Multi-temporal airborne structure-from-motion on caldera rim: Hazard, visitor exposure and origins of instabilities at Piton de la Fournaise

International audiencePiton de la Fournaise is one of the world's most active and visited volcanoes. Its summit crater (Cratère Dolomieu), the main tourist attraction, underwent a major caldera collapse in 2007 and its rim is not yet stabilized. In order to assess the caldera rim instability risk for visitors, we followed its structural evolution from 2007 to 2015. Using aerial photogrammetry campaigns, we mapped the unstable sites very precisely, carried out a quantitative analysis of the temporal evolution of these instabilities, and assessed the risks for visitors. Considering the 2008-2015 period, four sites close to the crater's edge showed significant horizontal ground motion (0.5-2 m), fracture widening (average of 0.3-0.56 m) and large-scale mass wasting volumes (total of 1.8+0.1 Â 10 6 m 3). We infer two different processes at work: (1) to the west and north, toppling of the basalt units occurs after periods of fracture widening due to the combined effect of magmatic intrusions and long-term inflation/deflation cycles; (2) to the south and east, parts of the caldera rim slowly slide towards the caldera centre, with significant accelerations during periods of enhanced volcanic activity (in 2008-2010 and 2014-2015). The official observation platform is the most stable zone to overlook the Cratère Dolomieu. By contrast, the most frequently visited area of the rim (northwest) outside the official platform is also the most unstable

The effects of changes in consumption composition and growth in recycling on decoupling household consumption from its waste footprint

Worldwide, household consumption has significantly increased in the last decades while its composition has significantly changed. In France, economic growth (and therefore consumption growth) is a political objective. On the contrary, waste policies rather target reduction, in particular as to waste generation and waste disposal. Accordingly, decoupling household consumption growth from its waste footprint is a requirement to simultaneously achieve economic and waste policy targets. In this context, this study aims at assessing the effects of both changes in the composition of consumption and growth in recycling rates on the waste footprint of French households. Three models are combined. Firstly, the macro-econometric model “NEMESIS” is used to elaborate prospective economic scenarios by 2020. Three scenarios of economic trajectories for France are built, exclusively modifying the total volume of household consumption. In the meantime, three scenarios of consumption patterns are built, respectively assuming that i) composition remains constant from 2008 to 2020, ii) trends in consumption observed from 1980 to 2010 apply to the period 2008-2020, iii) some final consumption expenditures increase at arbitrarily chosen rates. Moreover, two models are specifically designed in order to calculate the waste footprint of French household consumption in these cases of economic scenarios by 2020. In the first place, an Input-Output model extended to waste is built in order to quantify waste from economic activities induced by household consumption. Quantities of waste to treatments are also differentiated in the model, so that scenarios of recycling can be implemented together with economic scenarios. Secondly a complementary coefficient-based model is built to compute waste generation and treatment (in ktonnes of waste) as a function of household consumption (in Meuros). The results highlight that if consumption trends observed over the last 30 years continue over the period 2008-2020, then they would favor “relative” decoupling between consumption and waste footprint in terms of dry recyclables, mixed wastes and organic wastes, and “absolute” decoupling in terms of mineral wastes. Three scenarios of recycling are additionally assessed in the framework of the economic scenarios, respectively considering the increase in recycling of source-sorted waste fractions, the increase in recovery at sorting centers and the increase in source-segregation. This assessment highlights that the increase in recycling rates would globally limit the effects of consumption growth on the demand for non-mineral waste disposal induced by French households over the period 2008-2020. However, changes in production structures would be additionally required in order to significantly decouple household consumption from its “waste disposal footprint” over the period 2008-2020. Please click Additional Files below to see the full abstract

How summit calderas collapse on basaltic volcanoes: New insights from the April 2007 caldera collapse of Piton de la Fournaise volcano

International audienceIn April 2007, Piton de la Fournaise volcano experienced a caldera collapse during its largest historical eruption. We present here a structural analysis both of the caldera and the surrounding area, and precise GPS data recorded with a dense GPS network specifically dedicated to the analysis of deformation related to the summit collapse structures. Despite a collapse of more than 300 m in the central zone, the geometry of the new caldera is similar in map view to that of the pre-existing collapsed structure, which was formed from the coalescence of several pit craters. The caldera shows an asymmetric inner geometry with sub-vertical walls in the NW quadrant and steep scarps composed of inward tilted blocks in the southern half. The presence of preserved polished surfaces on the lower part of the sub-vertical scarp indicates that it corresponds to the caldera north-western ring fault. The April 2007 caldera collapse led to the development and the reactivation of concentric fractures on the caldera rim, mostly along the southern limit of the caldera. GPS data show that fractures result from radial extensional stresses that are restricted within the first tens of meters of the caldera edge. GPS data also reveal that the caldera collapse was coeval with a centripetal deflation, whose magnitude is largest along the southern half of the caldera. The displacements recorded by GPS result from both a general deflation, due to magma withdrawal from Piton de la Fournaise's summit magma chamber, and additional local effects related to the caldera collapse. Comparison of the caldera collapses at Piton de la Fournaise, Miyakejima and Fernandina reveals striking similarities, with cyclic seismic signals accompanying small-scale deflation–inflation cycles. This strongly suggests a common mode of collapse. Hence, we propose a unifying model of caldera collapse in basaltic setting, in which the inward deflation due to magma withdrawal from the magma chamber prevents the collapse of the caldera roof until the gravitational stress acting on the rock column above the magma chamber exceeds the shear strength along pre-existing ring faults. The downward displacement stops when the pressure increase into the magma chamber is able to again sustain the rock column. The succession of (1) inward deflation that prevents the collapse, (2) collapse due to gravitational stress and (3) stopping of the downward motion is repeated many times. The frequency of the cycles is influenced by the rate of magma withdrawal and by the amount of intrusion of magma along the ring faults

Explosive activity of the summit cone of Piton de la Fournaise volcano (La Réunion island): A historical and geological review

International audienceSummit explosive activity and collapses that form pit craters and calderas represent major volcanic hazards on a dominantly effusive, frequently active volcano like Piton de la Fournaise. Only three summit collapse events (1986, 2002, 2007) have been recorded since the foundation of the Piton de la Fournaise volcano observatory (OVPF) in 1979, and two of them (1986 and 2007) were associated with weak phreatic activity. At Piton de la Fournaise, the normal explosive activity consists of short-lived and mild (< 20 m-high) lava fountains, which quickly evolve into strombolian activity during the eruptions. Based on comprehensive literature review and high-resolution image analysis of surface outcrops and summit caldera walls, we reconstructed the time distribution of recent explosive events (phreatomagmatic; phreatic) and their link with summit collapses and lateral (flank) effusive eruptions. In historical time (post-1640 CE), we recognise two main clusters of explosive events. Frequent and violent phreatomagmatic to phreatic explosions occurred during the oldest cluster (1708–1878) and alternated with long-lasting periods (years to decades) of summit effusive activity. In contrast, scarce, and on average, weak explosions occurred during the youngest cluster (1897–2012), when discrete and short-lived (< 6 months) effusive eruptions represent the main eruptive dynamics. Historical summit collapses (pit craters and caldera), all localised at the top of the summit cone, were related to voluminous lateral eruptions and were followed by a significant decrease in eruptive rate. However, magma draining during lateral eruptions was not systematically associated with summit collapses or explosions. The long-lasting occurrence of magma at very shallow depth below the volcano summit, followed by a rapid lateral drainage, apparently represents a critical condition favouring magma–groundwater interaction to produce explosive activity. The prehistoric growth of the Piton de la Fournaise summit cone results chiefly from long-lasting to continuous activity, centred below its western side (Bory crater containing lava lakes). High lava fountains, long-lasting effusive activity, lava lakes, ash plumes and block ejections were common types of eruptive dynamics in the historical past, between 1640 and 1878. In this perspective, short-lived, small volume eruptions and long pauses, up to six years, during the last century of activity of Piton de la Fournaise can be considered as a lull, despite the high frequency of eruption (1 eruption/9 months on average). Temporal and spatial variations in recurrence rate and eruptive dynamics of basaltic volcanism, such as those recognised at Piton de la Fournaise, should be considered in the formulation of hazard assessments and in the interpretation of precursory patterns

Direct sediment transfer from land to deep-sea: Insights into shallow multibeam bathymetry at La Réunion Island

International audienceSubmarine canyon heads are key areas for understanding the triggering factors of gravity currents responsible for the transfer of detrital sediment to the deep basins. This contribution offers a detailed picture of canyon heads off La Réunion Island, with high-resolution multibeam bathymetry in the water depth range of 4-220 m. The present feeding of the Cilaos turbidite system, one of the largest modern volcaniclastic systems in the world, is deduced from morphological and sedimentological interpretations of newly acquired data. The study highlights small-scale sedimentary features indicating hydrodynamic and sedimentary processes. A direct connexion between the Saint-Etienne river mouth and submarine canyons is evidenced by the complete incision of the shelf and the presence of canyon heads connected to the modern deltaic bar. This direct connection, supplied by river torrential floods (cyclonic floods every two or three years), suggests the continuity of high-density fluvial flows to submarine gravity flows, forming hyperpycnal flows in the canyon. The initiation of secondary submarine gravity flows by storm waves (large austral waves and cyclonic waves) is also proposed for submarine canyons with large canyon heads developed in the surf zone from a sandy coastal bar. Bedforms in active canyon axis are considered as an indicator of the frequent activity of high-density turbidity currents. Moreover, a morphological record of last glacial and deglacial sea level variations is preserved, and particularly the Last Glacial Maximum sea level with the presence of small vertical cliffs, observed in this bathymetric data, which likely corresponds to a paleo-shoreline or paleo-reefs

Decision Support System for technology selection based on multi-criteria ranking: Application to NZEB refurbishment

Refurbishing existing building into Near Zero Energy Building (NZEB) is a key objective for the European Union. In order to achieve high rate of conversion, new refurbishment process must allow Decision Makers (DMs) (architects or designers) to sort through an ever increasing list of new technologies while taking into account uncertain preferences from multiple stakeholders. A Decision Support System (DSS) based on Multi-Criteria Decision-Making (MCDM) approaches is proposed. The DSS enables the DMs to browse the solutions space by selecting the relevant criteria, order them by preferences and specify the granularity in the assessment of the technologies regarding each criteria. This DSS is based on a ranking algorithm that operates on multiple types of quantitative (continuous, discrete, or binary) and qualitative (nominative or ordinal) variables from technological and human sources. An online user interface allows the real-time exploration of the solution space. A sensitivity analysis of the algorithm is conducted to expose the influence of the ranking algorithm parameters and to demonstrate the robustness of this algorithm. The proposed DSS is eventually implemented and validated through a use case concerning the choice of insulating materials considering heterogeneous criteria that model sustainable constraints.REfurbishment decision making platform through advanced technologies for near Zero energy BUILDing renovatio

Apprendre en faisant - Présentation d'une démarche pédagogique dans l'enseignement supérieur intégrant un projet pluri-technologique trisannuel

ESTIA, école d'ingénieurs généralistes, a récemment ouvert une formation Bachelor de Technologies. Les modules d'enseignement ont été définis autour d'un Projet Fil Rouge (PFR), projet pluritechnologique trisannuel, s'inscrivant dans la mouvance actuelle de l'apprentissage par projet. Dans ce contexte, le principal défi concerne la démarche pédagogique à mettre en oeuvre pour assurer l'application de connaissances théoriques au travers du PFR. Un sujet de PFR est proposé à chaque promotion entrante. Sur trois années, les étudiants appliquent les connaissances théoriques sur les différentes étapes de conception et de réalisation d'un système pluri-technologique, de la conception préliminaire à la démonstration de fonctionnement. Cette communication détaillera le modus operandi, en s'attachant à illustrer les particularités de la démarche employée. Citons, par exemple, la démonstration finale du système par les étudiants devant un jury composé d'industriels, ou encore l'usage obligatoire des langues étrangères dans le suivi du projet en deuxième année de cycle. Cette démarche a été expérimentée par une première promotion, qui a travaillé sur la conception et la réalisation d'un système de livraison autonome du courrier. Les résultats obtenus, tant sur la réalisation que sur l'intégration des premiers diplômés Bachelor en Cycle Ingénieur sont prometteurs, et les perspectives d'évolution nombreuses

Toxicity report of once weekly radiation therapy for low-risk prostate adenocarcinoma: preliminary results of a phase I/II trial

<p>Abstract</p> <p>Background</p> <p>Increasing clinical data supports a low α/β ratio for prostate adenocarcinoma, potentially lower than that of surrounding normal tissues. A hypofractionated, weekly radiation therapy (RT) schedule should result in improved tumour control, reduced acute toxicity, and similar or decreased late effects. We report the toxicity profile of such treatment.</p> <p>Materials and Methods</p> <p>We conducted a multi-institution phase I/II trial of three-dimensional conformal radiation therapy (3D-CRT) for favourable-risk prostate cancer (T1a-T2a, Gleason ≤ 6 and PSA < 10 ng/ml). RT consisted of 45 Gy in nine 5 Gy fractions, once weekly. Primary end-points were feasibility and late gastrointestinal (GI) toxicity (RTOG scale), while secondary end-points included acute GI toxicity, acute and late genitourinary (GU) toxicity, biochemical control, and survival.</p> <p>Results</p> <p>Between 2006 and 2008, 80 patients were treated. No treatment interruptions occurred. The median follow-up is 33 months (range: 20-51). Maximal grade 1, 2, and 3 acute (< 3 months) GU toxicity was 29%, 31% and 5% respectively (no grade 4). Acute GI grade 1 toxicity was reported in 30% while grade 2 occurred in 14% (no grade 3 or 4). Crude late grade ≥ 3 toxicity rates at 31 months were 2% for both GU and GI toxicity. Cumulative late grade ≥ 3 GI toxicity at 3 years was 11%. Two patients had PSA failure according to the Phoenix definition. The three-year actuarial biochemical control rate is 97%.</p> <p>Conclusions</p> <p>Weekly RT with 45 Gy in 9 fractions is feasible and results in comparable toxicity. Long term tumour control and survival remain to be assessed.</p