Julien Perret | Institut Géographique National (IGN) (original) (raw)

Julien Perret

Uploads

Papers by Julien Perret

Research paper thumbnail of Fostering the use of methods for geosimulation models sensitivity analysis and validation

In recent years, there has been a significant increase in the development of methods to explore, ... more In recent years, there has been a significant increase in the development of methods to explore, validate, calibrate and optimize geosimulation models. These methods and tools remain, however, underused by simulation communities, despite an ever improved and easier access to high performance computation facilities. The OpenMOLE model exploration software (Reuillon et al., 2013) is one of the reliable approaches fully dedicated to promote these techniques. This presentation offers some feedback on the recent initiative of a researcher school in model validation, focused around models and practices linked to the OpenMOLE platform. We present the iterative exploration and validation protocol developed during the school, with methods of increasing refinement deployed on a toy geosimulation model (spatialized prey-predator agent-based model of a zombie infection, with multi-modeling paradigms to include diverse processes for agent behavior). First, we illustrate classical sensitivity ana...

Research paper thumbnail of Generating urban morphologies at large scales

The 2019 Conference on Artificial Life, 2019

At large scales, typologies of urban form and corresponding generating processes remain an open q... more At large scales, typologies of urban form and corresponding generating processes remain an open question with important implications regarding urban planning policies and sustainability. We propose in this paper to generate urban configurations at large scales, typically of districts, with morphogenesis models, and compare these to real configurations according to morphological indicators. Real values are computed on a large sample of districts taken in European urban areas. We calibrate each model and show their complementarity to approach the variety of real urban configurations, paving the way to multi-model approaches of urban morphogenesis.

Research paper thumbnail of A scala library for spatial sensitivity analysis

The sensitivity analysis and validation of simulation models require specific approaches in the c... more The sensitivity analysis and validation of simulation models require specific approaches in the case of spatial models. We describe the spatialdata scala library providing such tools, including synthetic generators for urban configurations at different scales, spatial networks, and spatial point processes. These can be used to parametrize geosimulation models on synthetic configurations, and evaluate the sensitivity of model outcomes to spatial configuration. The library also includes methods to perturb real data, and spatial statistics indicators, urban form indicators, and network indicators. It is embedded into the OpenMOLE platform for model exploration, fostering the application of such methods without technical constraints.

Research paper thumbnail of The 18th century Cassini roads and cities dataset

The evolution of infrastructure networks such as roads and streets are of utmost importance to un... more The evolution of infrastructure networks such as roads and streets are of utmost importance to understand the evolution of urban systems. However, datasets describing these spatial objects are rare and sparse. The database presented here represents the road network at the french national level described in the historical map of Cassini in the 18th century. The digitalization of this historical map is based on a collaborative platform methodology that we describe in detail. These data can be used for a variety of interdisciplinary studies, covering multiple spatial resolutions and ranging from history, geography, urban economics to the science of network

Research paper thumbnail of Cassini-Topology

Research paper thumbnail of Set of Exploration Data 5AD

Different set of data used for exploration, used for reproductibility

Research paper thumbnail of PARISH-RUIN.SVG

Research paper thumbnail of MAP_POPULATION_EN.PNG

Research paper thumbnail of PRIEURÉ.PDF

Research paper thumbnail of TERRAIN.PRJ

Research paper thumbnail of TALUS.PDF

Research paper thumbnail of FORET_COULEUR.PNG

Research paper thumbnail of WINDMILL-RUIN.SVG

Research paper thumbnail of VILLE_COULEUR.PNG

Research paper thumbnail of LEGEND_FR.PNG

Research paper thumbnail of VILLAGE_RUINE.PDF

Research paper thumbnail of RECTO_EN.TEX

Research paper thumbnail of LEGEND_EN.SVG

Research paper thumbnail of GALLOW.SVG

Research paper thumbnail of VILLAGE.PDF

Research paper thumbnail of Fostering the use of methods for geosimulation models sensitivity analysis and validation

In recent years, there has been a significant increase in the development of methods to explore, ... more In recent years, there has been a significant increase in the development of methods to explore, validate, calibrate and optimize geosimulation models. These methods and tools remain, however, underused by simulation communities, despite an ever improved and easier access to high performance computation facilities. The OpenMOLE model exploration software (Reuillon et al., 2013) is one of the reliable approaches fully dedicated to promote these techniques. This presentation offers some feedback on the recent initiative of a researcher school in model validation, focused around models and practices linked to the OpenMOLE platform. We present the iterative exploration and validation protocol developed during the school, with methods of increasing refinement deployed on a toy geosimulation model (spatialized prey-predator agent-based model of a zombie infection, with multi-modeling paradigms to include diverse processes for agent behavior). First, we illustrate classical sensitivity ana...

Research paper thumbnail of Generating urban morphologies at large scales

The 2019 Conference on Artificial Life, 2019

At large scales, typologies of urban form and corresponding generating processes remain an open q... more At large scales, typologies of urban form and corresponding generating processes remain an open question with important implications regarding urban planning policies and sustainability. We propose in this paper to generate urban configurations at large scales, typically of districts, with morphogenesis models, and compare these to real configurations according to morphological indicators. Real values are computed on a large sample of districts taken in European urban areas. We calibrate each model and show their complementarity to approach the variety of real urban configurations, paving the way to multi-model approaches of urban morphogenesis.

Research paper thumbnail of A scala library for spatial sensitivity analysis

The sensitivity analysis and validation of simulation models require specific approaches in the c... more The sensitivity analysis and validation of simulation models require specific approaches in the case of spatial models. We describe the spatialdata scala library providing such tools, including synthetic generators for urban configurations at different scales, spatial networks, and spatial point processes. These can be used to parametrize geosimulation models on synthetic configurations, and evaluate the sensitivity of model outcomes to spatial configuration. The library also includes methods to perturb real data, and spatial statistics indicators, urban form indicators, and network indicators. It is embedded into the OpenMOLE platform for model exploration, fostering the application of such methods without technical constraints.

Research paper thumbnail of The 18th century Cassini roads and cities dataset

The evolution of infrastructure networks such as roads and streets are of utmost importance to un... more The evolution of infrastructure networks such as roads and streets are of utmost importance to understand the evolution of urban systems. However, datasets describing these spatial objects are rare and sparse. The database presented here represents the road network at the french national level described in the historical map of Cassini in the 18th century. The digitalization of this historical map is based on a collaborative platform methodology that we describe in detail. These data can be used for a variety of interdisciplinary studies, covering multiple spatial resolutions and ranging from history, geography, urban economics to the science of network

Research paper thumbnail of Cassini-Topology

Research paper thumbnail of Set of Exploration Data 5AD

Different set of data used for exploration, used for reproductibility

Research paper thumbnail of PARISH-RUIN.SVG

Research paper thumbnail of MAP_POPULATION_EN.PNG

Research paper thumbnail of PRIEURÉ.PDF

Research paper thumbnail of TERRAIN.PRJ

Research paper thumbnail of TALUS.PDF

Research paper thumbnail of FORET_COULEUR.PNG

Research paper thumbnail of WINDMILL-RUIN.SVG

Research paper thumbnail of VILLE_COULEUR.PNG

Research paper thumbnail of LEGEND_FR.PNG

Research paper thumbnail of VILLAGE_RUINE.PDF

Research paper thumbnail of RECTO_EN.TEX

Research paper thumbnail of LEGEND_EN.SVG

Research paper thumbnail of GALLOW.SVG

Research paper thumbnail of VILLAGE.PDF

Log In