Model sensitivity and uncertainty analysis using roadside air quality measurements

Most of the air quality modelling work has been so far oriented towards deterministic simulations of ambient pollutant concentrations. This traditional approach, which is based on the use of one selected model and one data set of discrete input values, does not reflect the uncertainties due to errors in model formulation and input data. Given the complexities of urban environments and the inherent limitations of mathematical modelling, it is unlikely that a single model based on routinely available meteorological and emission data will give satisfactory short-term predictions. In this study, different methods involving the use of more than one dispersion model, in association with different emission simulation methodologies and meteorological data sets, were explored for predicting best CO and benzene estimates, and related confidence bounds. The different approaches were tested using experimental data obtained during intensive monitoring campaigns in busy street canyons in Paris, France. Three relative simple dispersion models (STREET, OSPM and AEOLIUS) that are likely to be used for regulatory purposes were selected for this application. A sensitivity analysis was conducted in order to identify internal model parameters that might significantly affect results. Finally, a probabilistic methodology for assessing urban air quality was proposed.

La réforme des systèmes d'approvisionnement et d'assainissement dans l'Union européenne

Ce chapitre s’intéresse à plusieurs pays de l’UE et souligne les principaux aspects de leur cadre institutionnel respectif concernant les activités d’appro-visionnement en eau et d’assainissement. Il fournit également des exemples de cas où la participation du secteur privé dans le domaine de l’eau a posé un pro-blème, et d’autres où le secteur public est en charge du réseau de distribution. Le choix des pays évoqués vise à présenter diverses expériences et divers contextes géopolitiques, de l’Europe méditerranéenne à l’Europe du Nord en passant par les pays d’Europe centrale et orientale. En outre, les pays choisis comptent à la fois d’anciens membres de l’Europe des 15 et des membres plus récents. La dernière partie du chapitre traite de l’infuence de la législation européenne sur la gestion et la fourniture de services de distribution en eau. [Introductory paragraph to paper - see Additional Information].

A life cycle model for product-service systems design

Western manufacturing companies are developing innovative ways of delivering value that competes with the low cost paradigm. One such strategy is to deliver not only products, but systems that are closely aligned with the customer value proposition. These systems are comprised of integrated products and services, and are referred to as Product-Service Systems (PSS). A key challenge in PSS is supporting the design activity. In one sense, PSS design is a further extension of concurrent engineering that requires front-end input from the additional downstream sources of product service and maintenance. However, simply developing products and service packages is not sufficient: the new design challenge is the integrated system. This paper describes the development of a PSS data structure that can support this integrated design activity. The data structure is implemented in a knowledge base using the Protégé knowledge base editor.