Science & Mathematics

L’épidémiologie d’intervention a pour objectif la détection précoce des situations d’alerte sanitaire afin d’apporter une aide à la décision pour le déclenchement d’une réponse visant à en limiter l’impact. Dans le domaine de la santé animale, l’épidémiologie d’intervention se développe sous l’influence d’enjeux sanitaires, économiques et de santé publique. La structuration des activités est nécessaire au développement performant de cette discipline.Dans ce contexte, un modèle pour la structuration opérationnelle de l’épidémiologie d’intervention a été développé selon les principes d’une méthode d’optimisation de la performance reconnue : l’approche processus. L’établissement de ce modèle a reposé sur l’identification des chaînes d’activités (processus) d’une épidémiologie d’intervention performante, adaptée à la santé animale, tout en capitalisant les acquis et les avancées de cette discipline dans le domaine de la santé publique. Ces chaînes d’activités ont été identifiées grâce à l’analyse qualitative rétrospective d’expériences en épidémiologie d’intervention dans différents domaines (santé publique, santé publique vétérinaire, santé animale), en réponse à des contextes variés.Ces analyses rétrospectives ont permis d’identifier des chaînes d’activités vectrices de performance en épidémiologie d’intervention. Ces activités ont été intégrées au modèle proposé pour la structuration opérationnelle de cette discipline.L’objectif serait désormais d’assurer la mise en œuvre des chaînes d’activités identifiées via un système intégré global, à même de détecter et de documenter toute maladie animale, ou menace liée aux animaux, et d’informer la prise de mesures adéquates pour son controle

We study parabolic aligned elements associated with the type-$B$ Coxeter group and the so-called linear Coxeter element. These elements were introduced algebraically in (Mühle and Williams, 2019) for parabolic quotients of finite Coxeter groups and were characterized by a certain forcing condition on inversions. We focus on the type-$B$ case and give a combinatorial model for these elements in terms of pattern avoidance. Moreover, we describe an equivalence relation on parabolic quotients of the type-$B$ Coxeter group whose equivalence classes are indexed by the aligned elements. We prove that this equivalence relation extends to a congruence relation for the weak order. The resulting quotient lattice is the type-$B$ analogue of the parabolic Tamari lattice introduced for type $A$ in (Mühle and Williams, 2019).

Presse « sauvage », « rebelle », libre, free, presse contre-institutionnelle ou contre-culturelle, underground ou souterraine, presse révolutionnaire, militante, gauchiste, presse alternative ou parallèle, contre-presse, antipresse... Les appellations abondent pour désigner la nébuleuse des journaux et revues apparus dans le sillage de Mai 68. En l’espace de quelques mois et pour une durée, en moyenne, à peine supérieure, des centaines de feuilles ont éclos qui ont porté les aspirations, les rêves, les revendications d’une génération cherchant les voies d’une nouvelle utopie. Cet article tente d’en décrire les modèles économiques, les principales figures, les modes de fonctionnement dans un effort tout à la fois de synthèse et de discrimination. Il soutient que l’« échec » supposé de cette presse nouvelle s’est en fait traduit par une diffusion de certains de ses traits dans l’ensemble des médias et de la société.

SCADA is one of a set of manufacturing-and-control systems that are used to monitor and control critical infrastructure. Such systems extensively utilise communications network protocols such as TCP/IP to interconnect a diverse array of components. A major forthcoming change within TCP/IP is the adoption of the IPv6 protocol and inevitably this change will affect SCADA systems. However IPv6 introduces its own set of vulnerabilities. Hence, given the scale and complexity of current SCADA systems, there is a need for organisations to be able to model and review the risks emanating from the propagation of identifiable vulnerabilities in IPv6 prior to actual operational deployment. This work shows how the required tools can be constructed by complementing the Information Security Management (ISM) risk modelling tool with the formal technique of Coloured Petri Nets (CPN). The results of the application of the tools in a case study confirm the utility of the approach.

The aim of this paper is to examine collaborative supply chain practices and their related ways of integrating an environmental dimension. Seven case studies were analysed relating to different stages of the supply chain (supply side, forward logistics, reverse logistics). We draw on “proximity economics”, a theoretical framework at the crossroads of spatial and industrial economics. Starting with a sample of (alleged) green collaborative initiatives taken from the specialised press in the SC field, and further studied through in-depth interviews, a typology of collaborative practices was developed and characterised in terms of forms of proximity. This typology enabled us to identify the preconditions for environmental collaborative practices in terms of the forms of proximity among the actors involved.

Activities concerned with the upgrading of final ion energies at existing Tandem facilities by the addition of high frequency linear accelerators are reviewed. Two typical examples of the normal conducting linacs, the Munich booster with an interdigital H-structure and the Heidelberg linac using independently phased spiral resonators, are discussed in more detail. A summary of further linac booster projects is given.

A study of multicomponent reacting channel flows with significant heat transfer and low Mach number has been performed using a set of direct and wall-resolved large-eddy simulations (LES). The Reynolds number based on the channel half-height and the mean friction velocity is Re(tau)=300 for DNS and Re(tau)=1000 for wall-resolved LES. Two temperature ratios based on the mean centerline temperature T(c) and the temperature at the wall, T(w), are investigated: T(c)/T(w)=1.1 for DNS and T(c)/T(w)=3 for wall-resolved LES. The mass/momentum/energy balances are investigated, specially showing the changes induced by multicomponent terms of the Navier-Stokes equations. Concerning the flow dynamics, the data support the validity of the Van Driest transformation for compressible reacting flows. Concerning heat transfer, two multicomponent terms arise in the energy conservation balance: the laminar species diffusion which appears to be negligible in the turbulent core and the turbulent flux of chemical enthalpy which cannot be neglected. The data also show that the mean composition of the mixture is at equilibrium state; a model for the turbulent flux of chemical enthalpy is then proposed and validated. Finally, models for the total shear stress and the total heat flux are formulated and integrated in the wall normal direction to retrieve an analytical law of the wall. This wall model is tested favorably against the simulation database.

A rotating, insulated power shaft developed for the Munich MP-Tandem is described. The shaft transfers energy at a rate of several kW to vacuum pumps and beam optical equipment in regions of high electrostatic potential and has now been running trouble free for over 3 500 h. The relatively simple design can be adapted for similar devices in horizontal or vertical electrostatic accelerators with a suitable column grading pitch. It can easily be upgraded for higher energy transfer rates.

In the framework of international trading, new regulations are being drawn up concerning safety and in order to prohibit counterfeit goods. Due to the short delays imposed by Customs, the trend is still toward paperless trading. As a consequence, a better process and software interoperability is needed between the different actors of trading (customer, supplier, Customs...); a first step in software interoperability consists in process modeling. This paper presents a pragmatic guideline to generating successfully the business process model. The original aspects are first to use BPMN (Business Process Modeling Notation) for the representation of all types of flows (and not only information flows), and second to propose BPMN business patterns for the international trading purpose.