Can dissonance engineering improve risk analysis of human–machine systems?

The paper discusses dissonance engineering and its application to risk analysis of human–machine systems. Dissonance engineering relates to sciences and technologies relevant to dissonances, defined as conflicts between knowledge. The richness of the concept of dissonance is illustrated by a taxonomy that covers a variety of cognitive and organisational dissonances based on different conflict modes and baselines of their analysis. Knowledge control is discussed and related to strategies for accepting or rejecting dissonances. This acceptability process can be justified by a risk analysis of dissonances which takes into account their positive and negative impacts and several assessment criteria. A risk analysis method is presented and discussed along with practical examples of application. The paper then provides key points to motivate the development of risk analysis methods dedicated to dissonances in order to identify the balance between the positive and negative impacts and to improve the design and use of future human–machine system by reinforcing knowledge

Thermal boundary effects on a GT liner structure

GT combustor liners are subjected to mechanical and thermal loads that damage the structure and reduce their operational life. Among those, the thermo-acoustic instabilities develop, generating pressure oscillations because of the interaction between heat release, acoustic waves and structure vibrations. The vibratory behaviour of the structure is the result of these phenomena and undergoes repeated reversals of the main deformation mechanisms as a function of the operating load of the engine. Monitoring and evaluating the operational load history and the life consumption rate of combustor components is essential to sustain a reliable risk-based maintenance in the GT combustion hardware. The non-linear material behaviour can activate possible interactions causing coupled damage mechanisms and become a life threatening mode of failure. A methodology for modelling both the dynamic and static behaviour of a GT cannular combustion chamber by utilizing a combined fluid-structure approach is presented in this study. Together with the calculation of the heat fluxes through the liner, the effects of the modifications at the thermal boundary conditions were used to investigate the modifications in the liner structural properties and the stresses development at different GT loads. The monitored pressure oscillations during operations has been investigated by performing both acoustic and structural dynamics. A correlation with the observed failure has been proposed by investigating stress relaxation phenomena’s, creep and plastic effects for base load and part load operations

Perpignan – Saint-Sauveur

L’opération de diagnostic de l’église Saint-Sauveur se déroule en deux tranches opérationnelles. Cette notice fait état des découvertes réalisées au sein de la cour de l’ancienne école élémentaire. Cette cour, attenante à la nef de l’église au sud, est implantée sur une partie du cloître de l’ancien couvent des nonnes de Saint-Sauveur. La surface globale prescrite est de 165 m2. Une fenêtre d’observation de 88 m2 a été ouverte. Sur la majeure partie, le niveau du décapage a été fixé sous les ..

Espondeilhan – Zac du Levant (tranche 1)

Le diagnostic de la tranche 1 de la Zac du Levant a livré les vestiges d’une parcelle agricole exploitée dès le courant du haut Empire. La répartition spatiale régulière des fosses, respectant des intervalles de 8 m, et leurs gabarits orientent l’interprétation de ces vestiges comme appartenant à un ancien verger ou à une oliveraie pouvant comporter entre 50 et 60 plants. Le fossé observé sur le terrain, précédant la limite parcellaire encore en usage actuellement, en marque la limite occiden..

Traînou – Clos du Vieux Moulin

Le site du Clos du Vieux Moulin n’a été occupé que durant la période médiévale. L’occupation se met en place dans le courant des xie-xiie s., au carrefour de deux voies déjà présentes, et toujours en usage actuellement (la rue du Vieux-Moulin et le chemin de l’Orme Creux). Durant la première période d’occupation (xie s.), il n’a pas été observé d’éléments fossoyés structurant l’espace. Deux bâtiments sur poteaux ont été mis au jour à l’ouest de l’emprise de fouille. Le premier, dégagé partiel..

Neuville-aux-Bois – Sud de Montfort, Les Selliers

Cette seconde phase de l’intervention, commencée en 2007, a permis la fouille sur 4 370 m2 d’environ 500 vestiges appartenant à un hameau situé en bordure de chemin dont l’occupation s’étend entre la fin xie s. et le milieu du xiiie s. L’évolution des principaux éléments structurants (notamment les chemins et les enclos fossoyés) et les datations céramiques obtenues permettent de supposer trois périodes principales d’occupation. Ce hameau, apparu ex nihilo à la fin xie s., est formé par au mo..

Transversity Measurements at COMPASS

The measurement of transverse spin effects in semi-inclusive deep-inelastic scattering is an important part of the COMPASS physics program. From the analysis of the 2002-2004 data, new results for the transverse target spin asymmetry of z-ordered identified pion and kaon pairs are presented. In addition, a first result for the transverse target spin asymmetry of exclusively produced rho^0 mesons on the deuteron is shown.Comment: Proceedings of Photon07, Paris, 200

Dissonance Engineering: A New Challenge to Analyse Risky Knowledge When using a System

The use of information systems such as on-board automated systems for cars presents sometimes operational risks that were not taken into account with classical risk analysis methods. This paper proposes a new challenge to assess risks by implementing an automated tool based on the dissonance engineering principle. It consists in analysing knowledge in term of dissonances. A dissonance is defined as a knowledge that sounds wrong, or in other words that may present conflicts. The paper focuses on two kinds of dissonances: erroneous affordances when events can be related to erroneous actions and contradictory knowledge when the application of knowledge relates to opposite actions. The proposed automated tool analyses the knowledge base content in order to detect possible dangerous affordances or contradictory knowledge. An example of application is given by using a limited number of simple rules related to the use of an Automated Speed Control (ASC) system for car driving