References of "Medard de Chardon, Cyrille 40021051"
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See detailA multi-scale fine-grained LUTI model to simulate land-use scenarios in Luxembourg
Gerber, Philippe; Caruso, Geoffrey UL; Cornélis, Eric et al

in Journal of Transport and Land Use (2018), 11(1), 255272

The increasing attractiveness of Luxembourg as a place to work and live puts its land use and transport systems under high pressure. Understanding how the country can accommodate residential growth and ... [more ▼]

The increasing attractiveness of Luxembourg as a place to work and live puts its land use and transport systems under high pressure. Understanding how the country can accommodate residential growth and additional traffic in a sustainable manner is a key and difficult challenge that requires a policy relevant, flexible and responsive modelling framework. We describe the first fully fledged land-use and transport interaction framework (MOEBIUS) applied to the whole of Luxembourg. We stress its multi-scalar nature and detail the articulation of two of its main components: a dynamic demographic microsimulation at the scale of individuals and a micro-spatial scale simulation of residential choice. Conversely to traditional zone-based approaches, the framework keeps full details of households and individuals for residential and travel mode choice, making the model highly consistent with theory. In addition, results and policy constraints are implemented at a very fine resolution (20m) and can thus incorporate local effects (residential externalities, local urban design). Conversely to fully disaggregated approaches, a linkage is organized at an intermediate scale, which allows one (1) to simplify the generation and spatial distribution of trips, (2) to parallelize parts of the residential choice simulation, and (3) to ensure a good calibration of the population and real estate market estimates. We show model outputs for different scenarios at the horizon 2030 and compare them along sustainability criteria. [less ▲]

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See detailBicycle sharing system ‘success’ determinants
Médard de Chardon, Cyrille UL; Caruso, Geoffrey UL; Thomas, Isabelle

in Transportation Research. Part A : Policy & Practice (2017), 100

Many municipalities assert bicycle sharing systems (BSS) as having many benefits, justifying their adoption, yet few explicitly state the purpose of their system making comparison or determination of ... [more ▼]

Many municipalities assert bicycle sharing systems (BSS) as having many benefits, justifying their adoption, yet few explicitly state the purpose of their system making comparison or determination of success impossible. In addition, the apprehension of many BSS operators to share data further hinders comparison. This paper estimates the number of daily trips from publicly available data for 75 BSS case studies across the world and provides trips per bike per day scores as a comparison of performance and success. Results reveal that a third of case studies have fewer than the psychologically important one trip per bicycle per day. To ascertain what factors are associated with this metric we estimate models with independent variables related to system attributes, station density, weather, geography and transportation infrastructure. Our analysis provides strong evidence undermining the ‘network effect’ promoted by influential BSS policy makers that expanding system size increases performance. Finally our results describe and discuss causal variables associated with higher BSS performance. [less ▲]

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See detailBike-share rebalancing strategies, patterns, and purpose
Medard de Chardon, Cyrille UL; Caruso, Geoffrey UL; Thomas, Isabelle

in Journal of Transport Geography (2016), 55

We provide a first spatio-temporal exploration of bicycle sharing system (BSS) rebalancing patterns from data extracted for individual stations at a fine temporal scale and operator interviews. Analyzing ... [more ▼]

We provide a first spatio-temporal exploration of bicycle sharing system (BSS) rebalancing patterns from data extracted for individual stations at a fine temporal scale and operator interviews. Analyzing rebalancing operations for nine BSS, we describe implications for operators, municipalities, and future optimization work. We find that stations adjacent to transit hubs receive disproportionate amounts of rebalancing relative to trips and that rebalancing is more often responding to morning and afternoon demand exceeding station dock capacities rather than longer term accumulations of bicycles. More importantly, we observe some operator’ rebalancing behaviors constrained between opposing goals of maximizing trips, profits, and service level agreements. Many BSS have no explicitly defined purpose, but existing rebalancing strategies can support or clash with the purpose or suggested benefits of a BSS. [less ▲]

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See detailA Geographical Analysis of Bicycle Sharing Systems
Médard de Chardon, Cyrille UL

Doctoral thesis (2016)

This thesis evaluates the performance of bicycle sharing systems (BSS), autonomous systems of accessible bicycles that can be easily used for one way trips, and determines whether they are successful at ... [more ▼]

This thesis evaluates the performance of bicycle sharing systems (BSS), autonomous systems of accessible bicycles that can be easily used for one way trips, and determines whether they are successful at achieving promoted social and environmental outcomes through quantitative and qualitative methods. Such systems are typically surrounded by positive narratives of success, health, environmental and social benefits. This work challenges these notions. This thesis begins with the formalisation of BSS station level and trip data revealing alternative data contained within. Combined with spatiotemporal data analysis, this allows the estimation of trips, a potential measure of success. Due to most operators not providing consistent or comparable metrics of usage this work opens this heavily promoted technological transport innovation’s performance for public scrutiny. Performance estimates of 75 case studies show a majority having less than two trips per day per bicycle, suggesting a poor investment, regardless of existing social justice issues and exaggerated environmental benefits. Using this metric this work determines which attributes impact performance. While station density and cycling infrastructure, among others, are found to impact performance, results challenge promoted practice. Formalisation yielded rebalancing, the moving of bicycles to adjust to demand exceeding supply. Spatiotemporal data analysis and interviews with operators provides the first description of applied rebalancing, providing an alternative perspective to the many theoretical optimisation models. Results show rebalancing is spatially selective and influencing BSS outcomes, potentially contrary to its purpose. Finally, this thesis, through a critical urban sustainability perspective, presents darker aspects of BSS, beyond the golden narratives, showing conflicts of interest, controversy and the commercialisation of an initially environmental and anti-consumerism concept. Existential questions are raised due to BSS, mostly privately operated, providing benefits to an already advantaged class while public space is privatised and urban advertising increased. This work concludes by suggesting that alternative investment to bicycle sharing systems, such as cycling infrastructure, may be more beneficial and just. [less ▲]

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See detailEstimating bike-share trips using station level data
Medard de Chardon, Cyrille UL; Caruso, Geoffrey UL

in Tranportation Research Part B: Methodological (2015), 78

Bicycle sharing systems (BSS) have increased in number rapidly since 2007. The potential benefits of BSS, mainly sustainability, health and equity, have encouraged their adoption through support and ... [more ▼]

Bicycle sharing systems (BSS) have increased in number rapidly since 2007. The potential benefits of BSS, mainly sustainability, health and equity, have encouraged their adoption through support and promotion by mayors in Europe and North America alike. In most cases municipal governments desire their BSS to be successful and, with few exceptions, state them as being so. New technological improvements have dramatically simplified the use and enforcement of bicycle return, resulting in the widespread adoption of BSS. Unfortunately little evaluation of the effectiveness of differently distributed and managed BSS has taken place. Comparing BSS systems quantitatively is challenging due to the limited data made available. The metrics of success presented by municipalities are often too general or incomparable to others making relative evaluations of BSS success arduous. This paper presents multiple methodologies allowing the estimation of the number of daily trips, the most significant measure of BSS usage, based on data that is commonly available, the number of bicycles available at a station over time. Results provide model coefficients as well as trip count estimates for select cities. Of four spatial and temporal aggregate models the day level aggregation is found to be most effective for estimation. In addition to trip estimation this work provides a rigorous formalization of station level data and the ability to distinguish spatio-temporal rebalancing quantities as well as new characteristics of BSS station use. [less ▲]

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See detailOpening bicycle sharing system trip counts using station level data
Medard de Chardon, Cyrille UL

Scientific Conference (2014, August 28)

Bicycle sharing systems (BSS) have increased in number rapidly since 2007. The potential benefits of BSSs, sustainability, health and equity, have encouraged their adoption through support and promotion ... [more ▼]

Bicycle sharing systems (BSS) have increased in number rapidly since 2007. The potential benefits of BSSs, sustainability, health and equity, have encouraged their adoption through support and promotion by mayors in Europe and North America (NA) alike. In Europe BSSs are more often financed and operated by advertising companies than in NA where municipalities, non-profits and sub-contracted companies more often manage the systems. In both cases the municipal governments generally desire their BSSs to be successful and, with few exceptions, state them as being so. New BSS technological improvements to an old concept have dramatically simplified use and enforcement of bicycle return resulting in the widespread adoption of the first new form of public transportation in over a century. Unfortunately little time has been spent evaluating the effectiveness of differently distributed and managed BSSs risking that a poorly deployed BSS 'failure' alienate the concept within a municipality. Comparing BSS systems quantitatively is difficult due to the limited data made available. The metrics of success presented by municipalities are often too general or incomparable to others making relative evaluations of BSSs success difficult. This paper presents methodology allowing the estimation of the number of daily trips, the most significant measure of BSS usage, based on changes to the number of bicycles available at a station. By processing large amounts of data we open past trip data estimates and provide a simple methodology enabling public evaluation of future BSSs’ performances. [less ▲]

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See detailOptimal station localization for bicycle sharing system
Medard de Chardon, Cyrille UL

Scientific Conference (2013, September 07)

Many urban planning strategies for sustainable cities (New Urbanism, Mixed Use Development and Compact City) tout the need for smaller more compact communities [1, 2, 3]. These urban forms depend on a ... [more ▼]

Many urban planning strategies for sustainable cities (New Urbanism, Mixed Use Development and Compact City) tout the need for smaller more compact communities [1, 2, 3]. These urban forms depend on a modal shift from automobiles to walking and cycling. As this shift is unlikely to be driven by the markets, increases in sustainable modal transport, infrastructure and disincentives for driving [4] are necessary [5]. In some cities, bicycle sharing systems (BSS) have been catalysts for increasing cycling through their ability to extend existing public transit systems, encourage cycling accessibility and visibility. Cycling has many direct and indirect health benefits such as cardiovascular and reduced CO emissions, compared to car transport, respectively as well as social and equity benefits [6, 5:123]. BSSs are composed of bicycles and spatially fixed stations containing a constant number of docks. Two important advantages of the current generation BSSs are simplicity and security [7]; bicycle theft is difficult yet subscribers may checkout bicycles quickly and without difficulty, allowing users to seamlessly transfer between transport modes. The central question of this research is determining whether a mismatch occurs between BSS’s stations’ optimal locations based on origin and destination demands of potential cyclists and the existing stations. Most BSSs are being managed by private corporations, which often use advertising to subsidize the systems. BSS stations, or kiosks, often have double purposes of providing BSS services, such as checking out a bike, and displaying advertising. Effectively locating BSS stations throughout an urban fabric is of crucial importance to the adoption of the BSS. The optimal locations for advertising billboards and BSS stations are unlikely to consistently correspond. This conflict of interest has been explicitly anticipated by at least one city developing a BSS [8]. The overlap between optimal advertiser locations and stations for BSSs are destinations of high traffic such as commercial and transportation hubs. Conversely, BSS stations may insufficiently serve residential areas far from or without through-roads due to having decreased traffic and therefore marketing potential. This project addresses the question in three steps. The first is the gathering of spatial and spatio-temporal data related to cycling demand in order to develop demand surfaces. Next, demand is contrasted against existing BSS station infrastructure. Assessment is complex due to the alternate realities between data, theory and the practical operations of placing stations within available space constraints and the varying BSS priorities, such as social or racial equity, of cities. Finally we develop a model that optimally locates BSS stations for public use across the urban fabric based on demand and network distances between stations. Performing this process across multiple cities with BSSs we bring insight into whether a localization bias exists towards high throughput and advertising valued locations. Bicycle sharing systems may become the first new ubiquitous ‘public’ transport system in over a century. However, the initial privatization of this new transport system, whose impacts and evolution are not yet completely understood, may result in inefficiencies with lasting negative outcomes. The inadequate development of a city’s BSS may cause it to fail and stigmatize a progressive sustainable transport alternative for a generation. [less ▲]

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See detailFriendly Batch Routing (FBR)
Medard de Chardon, Cyrille UL; Caruso, Geoffrey UL

Software (2012)

The Friendly Batch Routing (FBR) application uses the Google Maps API to easily and simply gather route data for many origin-destination pairs. FBR is designed with usability in mind so that errors do not ... [more ▼]

The Friendly Batch Routing (FBR) application uses the Google Maps API to easily and simply gather route data for many origin-destination pairs. FBR is designed with usability in mind so that errors do not interrupt processing and skipped records can easily be resubmitted for processing. Additionally the FBR output can easily be imported into GIS packages. [less ▲]

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See detailAn iterative economic residential choice ABM of urban growth in Luxembourg (extended abstract)
Caruso, Geoffrey UL; Medard de Chardon, Cyrille UL

in Pinto N (Ed.) Proceedings of the Symposium on Cellular Automata Models of Urban and Spatial Systems (2012)

Detailed reference viewed: 39 (7 UL)