Category Archives: Non classé

EXPLAIN participates in the ATEC ITS congress on smart mobility

EXPLAIN delivered a presentation in the session dedicated to Traffic Control and Flow management. We introduced a dynamic macroscopic modelling approach that we devised to describe congestion on the motorways around Aix-Marseille-Méditerranée, under the impulse of the National Highway Authority (DIRMED).

On highly congested roads with a demand that may vary heavily with time of day, opting for a dynamic model over a static one provides substantial gains in accuracy. Nevertheless, for the model to be accurate, the variations of transport demand induced by a reconfiguration of a road or the network, or a regulatory measure, must be adequately described. This aspect is often discarded in dynamic models, although it has been established by several case studies across the world that the expected improvements following a road project are largely absorbed by the traffic thus induced. To take this into account, we have integrated the feedback of the traffic conditions on the transport demand in a dynamic traffic model, in order to test the impact of some contemplated regulation measures on the motorway binding Aubagne to Marseille (which is saturated in the morning rush hour). The model was applied with success and helped us define solutions for a better control a more efficient distribution of congestion across the network enabling for example better travel times on routes used by buses.

Traffic and Granular Flow conference (3-5 July 2019)

Explain consultancy aims to provide high-quality analysis and to be at the cutting edge of innovation. To this end, we keep tight contacts with the acadamic world. In particular, Explain will take part in the upcoming Traffic and Granular Flow, to be held at the University of Navarra, in Spain, from July, 3rd to 5th ; this major congress will gather leading scientists in the field of vehicular traffic, pedestrian and granular flows. Explain will deliver a talk in plenary session about salient features of dense pedestrian flows and the limitations of the models that are at the core of usual simulation software. Indeed, these models generally rest on force models, according to which pedestrians behave as self-propelled grains subjected to specific interactions with other pedestrians and the facility.

Such in-depth insight into the dynamic models implemented in simulation software and their range of validity is particularly useful to shed light on the complex problems of microscopic simulation that we deal with, whether it be the dimensioning of public facilities (stations, stadiums, etc.), the assessment of their safety in the event of an emergency or, more generally, any case of dynamic modelling.

EXPLAIN addresses the topic of the resilience of critical infrastructures

An innovation-driven consultancy eager to stay in contact with the latest developments in research, EXPLAIN will participate in the upcoming colloquium on « Crisis resilience and organisational reliability » on November 14th, 2018. The colloquium aims to bring together top public officials, actors on the ground and high-level academic researchers, with the prospect of fostering discussions and exchanges on major issues related to civil security. It is organised by the French Institute for Civil Security (Institut français de la sécurité civile, IFRASEC), the Engineers’ school CentraleSupélec, with support from the Department of Civil Security and Crisis Management (Direction générale de la sécurité civile et de la gestion des crises, DGSCGC) of the French Home Secretary, University Paris Saclay and la Maison des Sciences de l’Homme of University Paris Saclay.

EXPLAIN will address the topic of the resilience of critical infrastructures, in light of its expertise on pedestrian flows and building evacuations. This expertise, owned  by solving complex modelling problems, may be used in prospective studies aimong at the dimensioning, and the assessment of the safety in the event of an evacuation, of crowded facilities such as railway stations, stadiums and public buildings, with an approach that goes beyond the current state of the art.

Traffic studies for a new road in Clichy and Saint Ouen.

EXPLAIN has been chosen by Département des Hauts-de-Seine, to carry out the traffic studies for the project to create a new road in the towns of Clichy and Saint Ouen – in the Paris region.

The project is part of a context of strong development: a 100 ha eco-neighborhood on the banks of the Seine that plans to create 5,000 housing units and 10,000 jobs, a vast University Hospital Campus ‘Grand Paris Nord’ which aims to be an institution of excellence nationally and internationally.

EXPLAIN produces the traffic forecast expected in connection with the future urbanization program and designs the main intersections.

Extension of tramway line T1 in the Greater Paris

EXPLAIN has been chosen by the Department des Hauts de Seine to design all the junctions crossed by the future extension of tramway line T1 between Rueil and Nanterre in the Paris region.

The new section is 7,5 km mong and will include 15 stations for a total cost estimated at 370M€.

Our work follows a preliminary public consultation held in 2016-2017 and will feed into the public inquiry.

South Bordeaux Rail project : Explain chosen for the appraisal

The south Bordeaux rail project is estimated at 800 M€. It includes new tracks, improvement of existing stations, closing of railway crossing with the objective to increase frequency and reliability of trains between Bordeaux and Langon, Marmande and Agen.

EXPLAIN has been retained by SNCF Réseau to produce traffic forecast and the appraisal of the project.


Prospective transport study in the eastern part of the Paris region


An important growth of population and employment is expected in the eastern part of the Paris region near Marne-la-Vallée. To limit congestion and maintain quality of life, transportation networks will need to be adapted. EXPLAIN was chosen by the National government to work with local authorities to propose a Transportation Plan for 2025 and 2035.

EXPLAIN invited to meet French Minister of Transport

We were invited to present to the Transport Minister the innovations that we develop to serve mobility needs in all territories. EXPLAIN was invited by Elisabeth Borne together with three other startup companies developing innovative solutions for Mobility.