SharePoint
Aide
IRSN, Institut de radioprotection et de sûreté nucléaire

Search our site :

ok

Contact us :

ok
En Fr

Enhancing Nuclear Safety


Research

Publications

Representation and propagation of vague knowledge: what the theories of uncertain can bring to environmental sciences


Congress title :17èmes Journées Scientifiques de la Société d'Ecologie Humaine 
Congress town :Arles
Congress date :23/11/2005

Document type > *Congrès/colloque

Keywords >

Research Unit > IRSN/DEI/SESURE/LERCM

Authors > BAUDRIT Cédric, CHOJNACKI Eric, MERCAT-ROMMENS Catherine

Publication Date > 25/11/2005

Summary

The taking into account of uncertainties became a stage impossible to circumvent in the évaluation and risk management process. However, the realization of an analysis of uncertainties raises many technical difficulties because it often runs up against the limits of scientific knowledge and the formalization of some sources of uncertainties rests on an incomplète or subjective knowledge. Moreover, the propagation of vague knowledge, i.e. the characterization of its effect on the computation resuit, requires the use of théories still badly known in the field of environmental sciences, the théories of the uncertain. The présent communication proposes to présent the work completed for several years by the Institut de Radioprotection et de Sûreté Nucléaire (IRSN) in collaboration with the Bureau de Recherches Géologiques et Minières (BRGM), the Institut National de l'Environnement Industriel et des Risques (INERIS) and the Institut de Recherche en Informatique de Toulouse (IRIT - Université Paul Sabatier) on the représentation and the propagation of incomplète or vague information and its application in the case of the contamination of the food chain by a pollutant. The main objective of this work is to promote cohérence between the way in which information is mathematically represented and information really available. To achieve this objective, alternative methods are proposed to represent and propagate uncertainties. In particular, this work highiighted that the systematic use of probability distributions to represent environmental knowledge is often subjective and arbitrary and can resuit in underestimating the risk. To exceed this problem, the possibilities of use of various théories of uncertain were studied (probabilities, possibilities, functions of belief, p-boxes and fuzzy numbers). This utilisation required mathematical and numerical developments to elaborate tools usable for the représentation and the propagation of knowledge available in environmental sciences. Thèse tools will be described through their application to the case of the contamination of milk following a chronic strontium 90 deposit. This concrète example makes it possible to compare the impact of the différent mathematical methods and to discuss the difficulties of the use of the various kinds of results produced within the framework of the decision-making.

Close

Send to a friend

The information you provide in this page are single use only and will not be saved.
* Required fields

Recipient's email:*  

Sign with your name:* 

Type your email address:*   

Add a message :

Do you want to receive a copy of this email?

Send

Cancel

Close

WP_IMPRIMER_TITLE

WP_IMPRIMER_MESSAGE

Back

Ok