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This study examines how far the level of knowledge on a new public transport mode in Lebanon might affect mode choice. Indeed, passenger mode choice is a major issue associated with the effectiveness of new transport projects, as their level of effectiveness and feasibility will depend on the number of new adopters. This investigation is performed by developing mode choice models based on data collected via a questionnaire-based survey. The models were used to compare preferences among private cars, current public transport modes and a newly proposed Bus Rapid Transit system. The driving factors are divided into two categories: economic and psychological. The results reveal that explicit evaluations of several factors on the proposed transport modes yields mode choices different from direct evaluation. Besides, the structure of the utility function reveals that economic driving factors prevail over the psychological aspects, which is the opposite of what is observed with direct mode assessment. Moreover, people’s expectations of the proposed Bus Rapid Transit were significantly positive in terms of usability in addition to operational and economic reliability. This study shows that people’s level of knowledge of previous transport modes and their perceptual expectations of new travel modes must be taken into consideration in the feasibility studies of any transport implementations in the developing countries where the public transport services are discouraged.

International audience

This paper studies the impacts of the construction of a new highway on the built-up land use dynamics in the southern neighboring area of Beirut in Lebanon, whereas the impact of transport infrastructure on land use dynamics has been widely studied, few examples are found for developing countries where data are not widely available. Moreover, it is difficult to assess the impact of the infrastructure among several external and internal factors. Areas of built-up land use in Beirut Southern entrance in Lebanon were extracted from land use classification maps for years 1985 to 2019 using 30 m resolution satellite reflectance images in ArcGIS software. To compute an accessibility index to the population, average car travel speeds were determined for major local roads and population distributions were collected for years 2004 to 2019. Results revealed that after the completion of highway’s construction, the development of built-up land use has increased by 13.9%, but also that the land use dynamics depends highly on the unexpected arrival of Syrian refugees between years 2011 and 2013. The results were analyzed with the help of several interviews of stakeholders.

sMonitoring and understanding the evolution of land use and land cover is a key factor for many environmental studies as well as for policymakers. Moreover, policymakers are interested in understanding the factors that have a significant impact on land use change. This paper analyses the dynamics of land use change in Lebanon between the years 1984 and 2019 and identifies the main factors behind this process. The use of LandSat satellite images enables the creation of land use maps at several periods and the monitoring of the evolution of built up areas as well as of green areas. Five periods emerge from this analysis, for which it is possible to propose explanatory factors, after an in-depth qualitative analysis. Within the framework of Structural Equation Models, a Confirmatory Factor Analysis is carried out to determine the impacts of several factors related to governance and financial data. Moreover, the urban sprawl is further investigated and explained by cultural, environmental, and infrastructural factors. The main results reveal that the development of built up areas is highly dependent on good funding conditions, whereas banking conditions and weak governance are correlated. The case of Lebanon presents specificities probably linked to historical and cultural considerations that deserve to be studied in future works. In the form of recommendations, new land use policies should be enacted to ensure sustainability in the form of an equilibrium between the urban development, from one side, and the preservation of natural resources and good environmental conditions on the other side. This could comprise the preservation of natural zones; the subsidization of the cultivation profession; and the encouragement of urban densification instead of horizontal sprawl.

International audience

Le projet SOFT, sobriété énergétique par les formes urbaines et le transport, a abordé la question de la stratégieénergétique d’un territoire à l’aide d’un concept d’aménagement multi-échelle utilisant la géométrie fractale. Eneffet, les gains d’efficience classique (rénovation du bâti, performance des modes de transport, production localed’énergie) ne suffisent pas aujourd’hui pour assurer aux territoires une trajectoire carbone appropriée. Il estnécessaire de s’appuyer sur la sobriété énergétique, approche qui consiste à assurer la même qualité de vie auxhabitants, mais avec une baisse des consommations énergétiques qui peut s’accompagner d’une évolution despratiques. L’approche de la sobriété suppose de repenser la forme de la ville pour s’adapter à des contraintesmultiples : 1/ préservations des trames vertes et bleues, voire renforcement, puisqu’elles participent aurafraîchissement urbain, à la qualité de vie des habitants, et sont compatibles avec des pratiques de circuit courtcomme le maraîchage et l’agriculture urbaine, 2/ diversité des densité de logement et de population, de manièreà pouvoir mutualiser plus facilement des sources locale de production d’énergie, sans entraîner les inconvénientsdus à la densité (congestion, renchérissement des logements, îlots de chaleur), et 3/ organisation hiérarchiquedes centralités, des commerces, des emplois et des aménités, de manière à maximiser les mobilités douces, touten assurant la rentabilité économique des centres secondaires.L’approche développée dans SOFT repose sur le modèle fractalopolis, concept d’aménagement, auquel estassocié un logiciel opérationnel diffusé en open source. Les outils de fractalopolis permettent de créer au cas parcas un zonage multi-échelle adapté à chaque territoire, préservant des lacunes à différentes échelles pour lacontinuité des trames vertes et bleues, qui constitue une sorte de plan local d’urbanisme multi-échelle, décrivantune organisation hiérarchique fonctionnelle du territoire. Sur la base de ce zonage, il est possible d’estimer etd’ajuster un modèle de population pour avoir une répartition des logements en adéquation avec la hiérarchiespatiale proposée. Des évaluations d’accessibilité aux commerces et services sont effectuées, s’appuyant sur uneclassification fondée sur une hiérarchie théorique de besoin ainsi que sur les normes d’accessibilité présentesdans les documents d’urbanisme. Enfin, il est possible de faire évoluer la population, pour simuler une croissanceurbaine, ou de reconfigurer la répartition spatiale des services, de manière à comparer des scénarios.Le projet SOFT a appliqué ce concept au territoire d’Est-Ensemble, établissement public territorial situé à l’est deParis. La phase de diagnostic a révélé un territoire déjà dense, mais avec des diversités de paysages, fort de troisarcs verts, et avec une population très porteuse de changements, avec des associations des actives, y comprisdans le domaine de l’énergie. Le scénario spatial proposé vise donc à préserver et renforcer ces atouts, et s’appuiesur le prolongement à venir de la ligne 11 du métro qui modifiera les centralités existantes. Ce scénario laisse uneplace importante pour la production locale d’énergie, l’agriculture urbaine et le maraîchage, traditionnellementdéveloppés au sud du territoire. La piste du recyclage des excretas, plus novatrice et très cohérente avec ladynamique en place, a été explorée en détail. Les résultats des analyses incitent à préserver et renforcer lesspécificités du territoire. Les initiatives locales en faveur de l’énergie pourraient par ailleurs être soutenues par lamonnaie locale, la Pêche, ce qui renforcerait encore la cohésion et l’image de ce territoire en transition.Une partie des outils développés dans SOFT seront mobilisés à l’avenir en appui de bureaux d’études, notammentgrâce à l’implication d’Efficacity, partenaire du projet.

International audience; In travel surveys, immobility is often approached as a technical issue that needs to be dealt with in order to measure mobility more accurately. By covering mobility patterns over a full week, the 2008 French Travel Survey allows immobility to be analysed other than as a marginal and random phenomenon. For working days alone, 28.8% of the adults in the survey had experienced one or more immobility episodes. By considering the intensity of immobility, and by introducing latent variables into Structural Equation Modelling, we have been able to propose a model with reasonable explanatory power. Our findings agree with previous studies and also show that within suburban or rural areas, access to shops or the type of local residential fabric are also factors that influence the number of immobile days. In addition, our findings show that the effects of the determinants differ between categories of individuals, notably between working adults and students on the one hand, and between retired and non-working people on the other.

International audience; Much has been spoken and written about the rationalization and optimization of services and amenities in urban territories. In this context, there is increasing use of numerical modeling techniques addressing the design, selection and/or calibration of policy instruments. The question of the relations between appraisal tools and policymaking has been widely studied. However, few studies have specifically focused on the role of modeling in policymaking processes. Drawing on two case studies, this paper suggests a change in the nature of multi-expertise: neither conflicting nor cross-sectoral, we observed in both cases an interwoven configuration with a network of experts making use of integrated models. We call this configuration distributed expertise, arguing that it is a novel configuration and that its emergence is closely linked to the development of integrated modeling techniques. Other authors have discussed the idea that the growing need for new appraisal tools is linked with the proliferation of wicked policy problems. From our case studies we would conclude that the emergence of integrated modeling is not a response to complex problems but to complex systems of actors who need to reach a consensus on actions.

International audience; The present article looks to pinpoint explanatory factors for the sharing of escorting of children in dual-earner families. It proposes a detailed analysis of inequalities and interactions in dual-earner families when it comes to escorting children by taking into account the characteristics of trips to and from school for children, the characteristics of the parents’ occupations, and the characteristics of the household. Compared with earlier research, the model considers more detailed data about the escorts’ jobs, such as specific working hours, which provide a better understanding of the constraints on parents and insight into the choices made when both parents are in a position to escort their children. The findings depart somewhat from those of earlier work on the question because more specific data are considered. They show a marked gender inequality in escorting because mothers in dual-earner families do more than two-thirds of the escorting. But the factors explaining the sharing of escorting act almost symmetrically for both parents, with the effect of work starting and finishing times being preponderant. These models confirm that the inequality kicks in ahead of this: mothers in dual-earner households are more often than fathers in jobs with short working hours and which are more compatible with escorting.

International audience; In this article, we test the usability of a cartographic tool mixing maps and sounds. This tool is developed withinQuantumGIS as a plugin prototype. We first present some theoretical reflections about synesthesia. Secondly, weexplain the way we «sonificate» the images, by associating colors and recorded chords and sounds. Then we presentthe results of several usability tests in France with different users, including blind people. We finally conclude on thecontributions and the limitations of such a tool and draw some perspectives.

In Rio de Janeiro, immobility or the share of people with no journeys on any given day is very high (46%). Immobility has a marked geographical dimension in what is a segregated city. But income has only limited explanatory power. The population structure, with high proportions of people who are not in the labour force and who are unemployed, accounts for the high levels of immobility in the poor districts. Although population structure effects prevail, spatial factors such as the severance effect also account for differences between districts. Indeed, Rio de Janeiro features many different types of barriers that affect immobility in several districts and for several population groups. These barriers may be physical or symbolic and perceptive. This study proposes therefore to identify the scope of those barriers as they affect immobility. Our findings from the latest household travel survey available for the metropolitan area of Rio de Janeiro (2003) illustrate the effects of the two types of barrier, physical or symbolic and perceptive, on immobility that more specifically mark out certain categories of individuals such as housewives, the elderly, the unemployed or poor workers. Conversely, the wealthier active population seems to be little affected by the two types of barriers under study. Lastly, our results show that social fragmentation does not lead to greater immobility of favela populations in the heart of rich districts, but on the contrary to increased mobility, especially for the working age population in employment or looking for employment.

International audience; . Abstract The analysis of the evolution of transport networks can be performed by methods relating to the graph and network theory, for example by modelling the growth of the network or by analysing the evolution of global or local indices. However, this approach requires geographical databases representing the networks at different times. Maps are a natural source to create, by vectorisation, such geographical databases. We show in this article that, because of the particular nature of the cartographic representation that is a model of the territory rather than a mere image, it is necessary to explicitly take into account the modelling relation at the time of the map to be able to distinguish between the evolution of the territory and the art of the cartographer, rebuilding thus a kind of critical apparatus of the map.; L'analyse de l'évolution des réseaux de transport peut se faire par des méthodes issues de la théorie des graphes ou des réseaux, par exemple en modélisant la croissance du réseau ou encore en analysant l'évolution d'indicateurs globaux ou locaux au cours du temps. Cependant, cette approche nécessite de disposer de bases de données géographiques représentant les réseaux à différentes époques. Les cartes sont une source naturelle pour constituer, par vectorisation, de telles bases de données géographiques. Nous montrons dans cet article que, du fait de la nature particulière de la représentation cartographique qui est un modèle du territoire représenté et non une simple image, il est nécessaire de prendre en compte explicitement la relation de modélisation en vigueur à l'époque de la carte pour pouvoir faire la part de l'évolution du territoire et de l'art du cartographe, et reconstruire une sorte d'apparat critique de la carte.

This paper presents a new method for identifying urban fabrics based on population and build-up densities. It aims at creating a new zoning that embeds information about the composition of an urban area and its surroundings to help analyze the structuring role of transportation networks. The method allows for a more accurate characterization of areas sometimes ill-described in the zoning used in transportation studies. We developed a simple classification method transforming gridded data into radioconcentric grids thought to better fit European cities morphology. It provides a more adequate representation to retrieve urban fabrics. We apply our approach to datasets of the French cities of Besançon, Tours and Nancy, and compare the results to the zonings used in the last household travel surveys.; Cet article présente une méthode pour construire un zonage des tissus urbains sur la base des densités de population et de surfaces bâties. L'objectif est d'obtenir un zonage catégorisant l'étendue des agglomérations et de leur couronne périurbaine proche. Ce zonage se veut adapté pour l'analyse du rôle structurant des réseaux de transport et pour caractériser des zones périphériques parfois mal discriminées dans les zonages typiques des études de transport. La méthode répond à des critères de simplicité et d'indépendance vis-à-vis des maillages administratifs. Nous utilisons des densités initialement mesurées sur des grilles régulières, que nous transposons sur une grille radioconcentrique dont la structure morphologique semble plus adéquate pour caractériser et identifier les tissus urbains considérés. Testés sur les agglomérations de Besançon, Tours et Nancy, les zonages sont mis en situation par rapport aux découpages utilisés pour les dernières enquêtes ménages déplacements.

International audience; TOD (transit oriented development) is a land planning approach that aims at developing harmoniously a transit network and the land it deserves both at the local and at the regional scale. It has been implemented successful in several large North and South American cities. Its transposition to Europe and small to medium cities is not straightforward, especially because European cities are much more dense than American ones, and transit is already well developed. However, TOD can also be considered as a means to coordinate existing land use and transport planning, and this is a major issue for all cities whatever their size or their density. Indeed, there is a co-production relationship between transport and land use, and the city development is systemic with many feedback loops between its subsystems. We show in this paper that a medium-sized city such as Besançon in France can benefit from a TOD approach for its development by designing scenarios and evaluating hem with a LUTI model.

International audience; In this paper, we design a theoretical reflexion and an interactive exploration approach which joins maps and music to comprehend geographical space in a synesthesic way. Developed within Quantum GIS, the tool allows to extract spatial patterns of pixels on images and to sonorize space areas using soundscape signatures and musical compositions which suggest representations of real territories. RÉSUMÉ. Nous proposons d'associer carte et musique pour une meilleure appréhension synesthésique de l'espace géographique et dessinons les contours théoriques de cette ap-proche. Au sein du SIG Quantum GIS, l'outil cartographique interactif développé per-met, en analysant la composition des couleurs sur des portions d'images, de sonifier la carte et de renvoyer des compositions d'ambiances sonores ou de discours musical qui suggèrent des représentations de différents espaces vécus.

Digital Terrain Models constructed from contour lines often contain artifacts originating from their construction from irregularly spaced height measurements. We evaluate and illustrate these artifacts and their impact on terrain parameters. We provide algorithms to correct them as much as possible, and propose a methodology to predict areas where uncertainty still remains because of these artifacts. The analysis of these artifacts enables us to derive qualitative parameters such as "likely over-estimated", "likely underestimated", and "with no significant bias" on the DTM. Our method provides a qualitative description of local uncertainty, which is often more relevant for geographical applications than global quality parameters.

This paper introduces a new approach to 3D handling of geographical information in the context of risk analysis. We propose to combine several geometrical and topological models for 3D data to take advantage from their respective capabilities. Besides, we adapt from crystallography a high-level description of geographical features that enables to compute several metric and cardinal relations, such as the “lay on” relation, which plays a key-role for geographical information.

A large deviation expansion is used to evaluate the impact of errors in a geographical database on the computation of travel times. We work in the framework of discrete random variables and improve a theorem by Book to solve this problem. Simulations are provided to illustrate the methodology.

Resume Nous proposons dans cette Note un modele d'erreurs dans une base de donnees geographiques (BDG), et estimons l'erreur commise sur le calcul du temps de parcours d'un itineraire par un developpement de grandes deviations de sommes ponderees de variables aleatoires i.i.d. Etant dans le cadre de variables discretes, nous etendons pour cela un theoreme de Book [5]. Nous montrons sur un exemple la qualite de notre approximation.