Delaunay Tessellations and Voronoi Diagrams in CGAL

The Cgal library provides a rich variety of Voronoi diagrams and Delaunay triangulations. This variety covers several aspects: generators, dimensions and metrics, which we describe in Section 2. One aim of this paper is to present the main paradigms used in CGAL: Generic programming, separation between predicates/constructions and combinatorics, and exact geometric computation (not to be confused with exact arithmetic!). The first two paradigms translate into software design choices, described in Section 4, while the last covers both robustness and efficiency issues, respectively described in Sec- tion 6 and 7. Other important aspects of the Cgal library are the interface issues, be they for traversing a tessellation, or for interoperability with other libraries or languages, see Section 5. We present in Section 8 some tessellations at work in the context of surface reconstruction and mesh generation. Section 9 is devoted to some on-going and future work on periodic triangulations (triangulations in periodic spaces), and on high-quality mesh generation with optimized tessellations. Section 10 provides typical numbers in terms of efficiency and scalability for constructing tessellations, and lists the remaining weaknesses. We conclude by listing some of our directions for the future

Comparative diffusion assay to assess efficacy of topical antimicrobial agents against Pseudomonas aeruginosa in burns care

<p>Abstract</p> <p>Background</p> <p>Severely burned patients may develop life-threatening nosocomial infections due to <it>Pseudomonas aeruginosa</it>, which can exhibit a high-level of resistance to antimicrobial drugs and has a propensity to cause nosocomial outbreaks. Antiseptic and topical antimicrobial compounds constitute major resources for burns care but in vitro testing of their activity is not performed in practice.</p> <p>Results</p> <p>In our burn unit, a <it>P. aeruginosa </it>clone multiresistant to antibiotics colonized or infected 26 patients over a 2-year period. This resident clone was characterized by PCR based on ERIC sequences. We investigated the susceptibility of the resident clone to silver sulphadiazine and to the main topical antimicrobial agents currently used in the burn unit. We proposed an optimized diffusion assay used for comparative analysis of <it>P. aeruginosa </it>strains. The resident clone displayed lower susceptibility to silver sulphadiazine and cerium silver sulphadiazine than strains unrelated to the resident clone in the unit or unrelated to the burn unit.</p> <p>Conclusions</p> <p>The diffusion assay developed herein detects differences in behaviour against antimicrobials between tested strains and a reference population. The method could be proposed for use in semi-routine practice of medical microbiology.</p

La céramique antique de deux établissements ruraux en territoire ségusiave : Grand’Plantes à Fleurieux-sur-l’Arbresle et Les Fourches à Lentilly (Rhône)

Deux fermes antiques en territoire ségusiave, dont une particulièrement bien caractérisée, ont livré des lots de mobilier qui permettent de montrer l’évolution du faciès céramique depuis la fin du Ier s. av. J.-C. jusqu’au IIIe s. de notre ère. À proximité de la colonie romaine de Lugdunum, au sud, et de Forum Segusiavorum, la capitale de cité ségusiave, à l’est, les sites sont également dans l’aire d’influence de l’axe Rhône-Saône. L’étude des céramiques communes et une attention particulière aux pâtes ont révélé une grande variété de faciès morphologiques avec des influences de la vallée de la Loire, de Lyon et Vienne dans la vallée du Rhône mais aussi de la plaine de la Saône.Two Antique farms in the Segusiavi region, including one that is particularly well characterized, yielded artifact assemblages that show the evolution of the ceramic facies from the end of the 1st c. BC to the 3rd c. AD. Located near the Roman colony of Lugdunum to the south, and the Forum Segusiavorum, the capital of the Segusiavi city, to the east, the sites are also in the zone of influence of the Rhône-Saône axis. The study of the common ceramics, with specific attention paid to the clays, revealed a wide variety of morphological facies with influences from the Loire Valley, Lyon and Vienne in the Rhône Valley, as well as from the Saône plain.Die Keramikserien aus zwei antiken ländlichen Siedlungen auf dem Gebiet der Segusiaver, eine der beiden Siedlungen ist sehr charakteristisch, erlauben es die Entwicklung der Keramik vom Ende des 1. Jh. v. Chr. bis zum 3. Jh. n. Chr. zu nachzuverfolgen. Die Siedlungen liegen südlich der römischen Kolonie Lugdunum und östlich von Forum Segusiavorum, dem Hauptort der Segusiaver, und befinden sich zudem im Einflussbereich der Achse Rhône-Saône. Die Untersuchung der Gebrauchskeramik, bei der den verwendeten Tonen besondere Aufmerksamkeit gewidmet wurde, hat eine große morphologische Vielfalt mit Einflüssen des Loiretals, Lyon und Vienne im Rhonetal, doch auch der Saône-Ebene aufgezeigt

A Numerical Model of the SEIS Leveling System Transfer Matrix and Resonances: Application to SEIS Rotational Seismology and Dynamic Ground Interaction

Abstract Both sensors of the SEIS instrument (VBBs and SPs) are mounted on the mechanical leveling system (LVL), which has to ensure a level placement on the Martian ground under currently unknown local conditions, and provide the mechanical coupling of the seismometers to the ground. We developed a simplified analytical model of the LVL structure in order to reproduce its mechanical behavior by predicting its resonances and transfer function. This model is implemented numerically and allows to estimate the effects of the LVL on the data recorded by the VBBs and SPs on Mars. The model is validated through comparison with the horizontal resonances (between 35 and 50 Hz) observed in laboratory measurements. These modes prove to be highly dependent of the ground horizontal stiffness and torque. For this reason, an inversion study is performed and the results are compared with some experimental measurements of the LVL feet’s penetration in a martian regolith analog. This comparison shows that the analytical model can be used to estimate the elastic ground properties of the InSight landing site. Another application consists in modeling the 6 sensors on the LVL at their real positions, also considering their sensitivity axes, to study the performances of the global SEIS instrument in translation and rotation. It is found that the high frequency ground rotation can be measured by SEIS and, when compared to the ground acceleration, can provide ways to estimate the phase velocity of the seismic surface waves at shallow depths. Finally, synthetic data from the active seismic experiment made during the HP3 penetration and SEIS rotation noise are compared and used for an inversion of the Rayleigh phase velocity. This confirms the perspectives for rotational seismology with SEIS which will be developed with the SEIS data acquired during the commissioning phase after landing

A Pre-Landing Assessment of Regolith Properties at the InSight Landing Site

This article discusses relevant physical properties of the regolith at the Mars InSight landing site as understood prior to landing of the spacecraft. InSight will land in the northern lowland plains of Mars, close to the equator, where the regolith is estimated to be ≥3--5 m thick. These investigations of physical properties have relied on data collected from Mars orbital measurements, previously collected lander and rover data, results of studies of data and samples from Apollo lunar missions, laboratory measurements on regolith simulants, and theoretical studies. The investigations include changes in properties with depth and temperature. Mechanical properties investigated include density, grain-size distribution, cohesion, and angle of internal friction. Thermophysical properties include thermal inertia, surface emissivity and albedo, thermal conductivity and diffusivity, and specific heat. Regolith elastic properties not only include parameters that control seismic wave velocities in the immediate vicinity of the Insight lander but also coupling of the lander and other potential noise sources to the InSight broadband seismometer. The related properties include Poisson’s ratio, P- and S-wave velocities, Young’s modulus, and seismic attenuation. Finally, mass diffusivity was investigated to estimate gas movements in the regolith driven by atmospheric pressure changes. Physical properties presented here are all to some degree speculative. However, they form a basis for interpretation of the early data to be returned from the InSight mission.Additional co-authors: Nick Teanby and Sharon Keda

Development of a qualification methodology for complex systems by reliability tests

Le secteur du chauffage, de la ventilation et de la climatisation (Heating Ventilation and Air-Conditioning,HVAC) se doit, comme toute industrie d’envergure, de maîtriser la fiabilité de ses produits pour garantir un service optimal au client, réduire les délais de développement et maîtriser ses coûts. Pour ce faire, il est indispensable de connaitre et savoir appliquer les outils de fiabilité prévisionnelle, expérimentale et opérationnelle. Seule une méthodologie robuste permettant de définir une stratégie de qualification permet de garantir la tenue de l’objectif de fiabilité.La première partie de ce travail définit les problématiques ayant attrait à la fiabilité et fait l’inventaire des méthodes existantes dans des domaines connexes et surtout dans le domaine HVAC.Dans un second temps la méthodologie de qualification est proposée, avec un focus sur l’exploitation du retour d’expérience, la définition des objectifs de fiabilité et tous les plans d’essais possibles. Enfin, des exemples concrets mis en place chez CIAT (UTC) sont détaillées dans une dernière partie.The heating, ventilation and air conditioning (HVAC) field, as any other large industry, must control the reliability of its products in order to guarantee an optimal service to customers, reduce development limits and master its costs. To achieve it, predicted, experimental and operational reliability tools should be known and well applied. Only a strong methodology leading to a qualification strategy can ensure the holding of the reliability target. The first part of this work defines reliability terms and inventories existing methods in related fields and specifically in HVAC. Following that, the qualification methodology is detailed, focusing on feedback, definition of reliability targets and possible test plans. Finally, specific examples implemented at CIAT (UTC) are detailed in final part

Développement d’une méthodologie de qualification de systèmes complexes par des essais de fiabilité

The heating, ventilation and air conditioning (HVAC) field, as any other large industry, must control the reliability of its products in order to guarantee an optimal service to customers, reduce development limits and master its costs. To achieve it, predicted, experimental and operational reliability tools should be known and well applied. Only a strong methodology leading to a qualification strategy can ensure the holding of the reliability target. The first part of this work defines reliability terms and inventories existing methods in related fields and specifically in HVAC. Following that, the qualification methodology is detailed, focusing on feedback, definition of reliability targets and possible test plans. Finally, specific examples implemented at CIAT (UTC) are detailed in final part.Le secteur du chauffage, de la ventilation et de la climatisation (Heating Ventilation and Air-Conditioning,HVAC) se doit, comme toute industrie d’envergure, de maîtriser la fiabilité de ses produits pour garantir un service optimal au client, réduire les délais de développement et maîtriser ses coûts. Pour ce faire, il est indispensable de connaitre et savoir appliquer les outils de fiabilité prévisionnelle, expérimentale et opérationnelle. Seule une méthodologie robuste permettant de définir une stratégie de qualification permet de garantir la tenue de l’objectif de fiabilité.La première partie de ce travail définit les problématiques ayant attrait à la fiabilité et fait l’inventaire des méthodes existantes dans des domaines connexes et surtout dans le domaine HVAC.Dans un second temps la méthodologie de qualification est proposée, avec un focus sur l’exploitation du retour d’expérience, la définition des objectifs de fiabilité et tous les plans d’essais possibles. Enfin, des exemples concrets mis en place chez CIAT (UTC) sont détaillées dans une dernière partie

Stratégie de qualification d'un système complexe : application à la machine thermodynamique

International audienceCet article, dans le cadre d'une thèse CIFRE ANRT commune à l'entreprise CIAT et au laboratoire LARIS, propose une stratégie de qualification d'un système complexe à partir des données opérationnelles, avec comme cas d'application la machine thermodynamique. La donnée d'entrée sera le retour d'expérience. Puis, l'allocation de fiabilité sera pratiquée pour aboutir aux fiabilités visées. Ces dernières seront les données d'entrée de plans d'essais de démonstration (zérodéfaillance) par organes.</p

Culture & société dans la littérature policière (les romancières anglophones à la fin du XXe siècle)

L'Angleterre, pays urbanisé depuis deux siècles, a participé à la création et au développement du roman policier. A partir de 1960, une génération de femmes écrivains a apporté un nouveau souffle à ce genre d'écriture. Universitaires dotées d'une large et solide culture littéraire et artistique, elles insufflent dans ces romans basés sur l'observation minutieuse d'une société et d'une époque de nouvelles perspectives de lecture. La profondeur de champ s'enfonce dans notre histoire occidentale et parcourt par le biais des œuvres des grands maîtres de la peinture notre passé jusqu'à rejoindre les grands mythes qui en sont le fondement. Notre étude tente de montrer que ces écrivains en cette fin de millénaire voient dans le passage du temps une usure des grands principes originels, un désagrégation de la pensée et des sentiments fondateurs jusqu'à l'effacement, une dilution qui entraîne une chute de la psyché vers le néant.England, a country urbanised for two centuries, has been playing a part in the creation and the developing of the detective literature. Since 1960, a new generation of woman novelists has given a new spirit to this literary genre. Academics with a large and solid culture in Arts and classics, they introduce original perspectives in the reading of those novels based on a detailed observation of a society and a time. By means of the paintings of the most famous artists, the depth of the field plunges into our western history to meet the myths which compose its foundation. Our work tries to show that, at the end of the millennium, these woman novelists see the wearing effects of the time in our great basic principles, and the disintegration of the primeval thoughts, a thinning down that leads mankind to fall into the abyss.PAU-BU Lettres (644452101) / SudocSudocFranceF