On the definition of the standard atmosphere

On April 15, 1920, the under Secretary of State for Aeronautics and Aerial Transport decided to adopt as Standard Atmosphere for official airplane tests in France, the atmosphere defined by the following law, known as the Law of the S.T.You.(Technical Section of Aeronautics): From 0 to 11,000 m. - 0=15-0.0065 Z and above 11,000 m. - 0= -56.5 degrees being the temperature in centigrade degrees at altitude Z expressed in meters. For altitude 0 the pressure is 760 mm of mercury. In the magazine "L'Aeronautique" Mr. A. Toussaint has already written at length on the first studies which led to the elaboration of this law. Since that time the results obtained have been confirmed by fuller and more abundant data which have justified the official adoption of the Law of the S.T. You. The object of the present article is to give a summary exposition and discussion of the ideas and documents which form the basis of the question

Can Temporal Fine Structure and Temporal Envelope be Considered Independently for Pitch Perception?

One aim of higher education is to develop professional identities in students to equip them for future working life. Health professional students will work under financial pressures in a market-based environment, which can lead to conflicts with professional ethical values. This study explores how Swedish dental students perceive economic aspects of dentistry. The article is based on a study of undergraduate research projects. In the analysis of the projects, two themes were identified: (1) cost-effective organizing of dentistry and (2) costs and benefits of interventions. The students displayed socially responsible values by emphasizing the need for dentists to utilize resources effectively, which implies that professional education can support the development of the perception that economic values can be compatible with professional ethical values

An adaptive large neighborhood search for a full truckload routing problem in public works

International audienceThis paper presents a truck routing and scheduling problem faced by a public works company. Itconsists of optimizing the collection and delivery of materials between sites, using a heterogeneousfleet of vehicles. These flows of materials arise in levelling works and construction of roads networks.As the quantity of demands usually exceeds the capacity of a truck, several trucks are needed tofulfill them. As a result, demands are split into full truckloads. A set of trucks routes are needed toserve a set of demands sharing a set of resources, available at pickup or delivery sites, which can beloaders or asphalt finishers in our application cases. Thus, these routes need to be synchronized ateach resource. We propose an Adaptive Large Neighborhood Search (ALNS) to solve this problem.This approach is evaluated on real instances from a public work company in France

Efficient handling of synchronization in three vehicle routing problems

International audienceThis paper presents a synthesis of contributions to the solving of three vehicle routing problemsinvolving synchronization constraints. These problems are: the Pickup and Delivery Problem withTransfers (PDPT), studied during the PhD of Renaud Masson, co-advised with Olivier Péton [4], theTwo-Echelon Multiple-Trip Vehicle Routing Problem with Satellite Synchronization (2E-MTVRPSS),studied by Philippe Grangier during his PhD, co-advised with Michel Gendreau and Louis-Martin Rousseau [2], and the Heterogeneous Full Truckload Pickup and Delivery Problem with TimeWindows and Resource Synchronization(HFTPDPTW-RS), under study by Axel Grimault in hisPhD and co-advised with Nathalie Bostel [3]. All these problems have been solved with an AdaptiveLarge Neighborhood Search (ALNS).A special focus is given to the temporal feasibility evaluation of an insertion which has beenproposed for the PDPT [5] and extended to the other problems. The concept of forward time slack[6] is extended to provide a constant time feasibility test of temporal constraints. Experimentsconfirm the solving time reduction provided by the implementation of this test in a meta-heuristic

Sécurisation des parcours professionnels et flexicurité : analyse comparative des positions syndicales

Partant d’exploitations de « textes » syndicaux tels que documents de congrès, articles, notes et entretiens auprès des syndicalistes en charge de la question de la sécurisation des parcours professionnels, cet article analyse la place qu’occupe la flexicurité dans les positions de syndicats français de salariés. L’auteure revient, dans un premier temps, sur la généalogie des positions syndicales. Elle présente ensuite les positions syndicales sur la sécurisation des parcours professionnels, en mettant en évidence l’intention principale, l’orientation ou l’axe que chaque organisation privilégie aujourd’hui sur ce thème. L’article fournit également des éléments permettant de situer la position des organisations d’employeurs – Medef et CGPME en particulier. Enfin, il propose une « cartographie » des positions syndicales, afin de mieux distinguer les approches des uns et des autres.This article aims to analyse the way in which the idea of flexicurity is expressed in the stances adopted by the French trade unions, in the light of the various concepts that they use when discussing the issue of job security. It firstly reviewes the roots of the trade unions’ respective stances on flexicurity, not in an exhaustive fashion, but instead by highlighting each organisation’s main aim, focus and strategic area on this issue. Finally, the article includes a sort of “map” of the trade unions’positions, enabling their various approaches to be better distinguished. This in-depth examination highlights a sort of “structural equivalence” between the stance taken by each organisation in the field of labour relations, and the proposals or models it defends on the issue of flexicurity and job security

Neural changes associated with semantic processing in healthy aging despite intact behavioral performance

Semantic memory recruits an extensive neural network including the left inferior prefrontal cortex (IPC) and the left temporoparietal region, which are involved in semantic control processes, as well as the anterior temporal lobe region (ATL) which is considered to be involved in processing semantic information at a central level. However, little is known about the underlying neuronal integrity of the semantic network in normal aging. Young and older healthy adults carried out a semantic judgment task while their cortical activity was recorded using magnetoencephalography (MEG). Despite equivalent behavioral performance, young adults activated the left IPC to a greater extent than older adults, while the latter group recruited the temporoparietal region bilaterally and the left ATL to a greater extent than younger adults. Results indicate that significant neuronal changes occur in normal aging, mainly in regions underlying semantic control processes, despite an apparent stability in performance at the behavioral level

Optimisation de tournées de camions complets dans le secteur des travaux publics

In 2013, the transportation of materials for roads construction and earthwork represents more than half of the whole activity of in the public works sector. Optimization methods for vehicle routing problems allow to solve big-size problems with industrial sector constraints. In this thesis, we focus on solving the rich full truckload pickup and delivery problem with resource synchronization. First, we solve this vehicle routing problem with a two phase heuristic method. Then, we study the integration of regulation of drivers’ working hours and the addition of lunch breaks in routes of vehicles. These methods are tested on instances from the literature and real life instances from a public works company.Le transport de matériaux pour la réalisation d’infrastructures routières et le terrassement représente, en 2013, plus de la moitié de l’activité du secteur des travaux publics. Les méthodes d’optimisation de tournées de véhicules permettent aujourd’hui de résoudre des problèmes de grandes tailles en intégrant les contraintes liées au métier. Dans cette thèse, nous nous intéressons à la résolution du problème riche de collectes et livraisons en camions complets avec des contraintes de synchronisation sur les ressources. Dans un premier temps, nous résolvons le problème de tournées de véhicules avec une méthode heuristique en deux phases. Dans un second temps, nous étudions l’intégration des contraintes liées aux temps de conduite des chauffeurs ainsi que l’ajout des pauses déjeuners aux tournées. Nous testons les algorithmes proposés sur des instances de la littérature et des instances réelles issues d’une application industrielle d’une entreprise de Travaux Publics

Auditory Stream Segregation and the Perception of Across-Frequency Synchrony

This study explored the extent to which sequential auditory grouping affects the perception of temporal synchrony. In Experiment 1, listeners discriminated between 2 pairs of asynchronous "target" tones at different frequencies, A and B, in which the B tone either led or lagged. Thresholds were markedly higher when the target tones were temporally surrounded by "captor tones" at the A frequency than when the captor tones were absent or at a remote frequency. Experiment 2 extended these findings to asynchrony detection, revealing that the perception of synchrony, one of the most potent cues for simultaneous auditory grouping, is not immune to competing effects of sequential grouping. Experiment 3 examined the influence of ear separation on the interactions between sequential and simultaneous grouping cues. The results showed that, although ear separation could facilitate perceptual segregation and impair asynchrony detection, it did not prevent the perceptual integration of simultaneous sounds. Keywords: perceptual organization, auditory perception, stream segregation, asynchrony Sensitivity to seemingly low-level sensory features in a scene can be profoundly influenced by the way in which the scene is perceptually organized. A striking example of this in visual perception relates to the finding by In the auditory modality, one of the most compelling examples of the influence of perceptual organization on sensitivity comes from demonstrations that listeners are largely unable to correctly perceive the relative timing of sounds that form part of separate perceptual "streams." The first lines of evidence for this were provided b