HoanKiemAir : simulating impacts of urban management practices on traffic and air pollution using a tangible agent-based model
2020 RIVF International Conference on Computing and Communication Technologies (RIVF)
Pham Minh Duc
/Chapuis, Kevin
/Drogoul, Alexis
/Gaudou, Benoît
Grignard, A.
/Marilleau, Nicolas
/Nguyen-Huu, Tri
Pedestrian zones are present in numerous cities around the world, and Hanoi city began to organize one a few years ago. However, closing roads can lead to heavy traffic congestion in surrounding areas and, consequently, more air pollution in these areas. There is, therefore, a need for analyzing and predicting the outcomes in terms of air pollution when certain roads are closed, before actually implementing a plan. In this project, we used the GAMA platform to build an agent-based model that simulates the traffic and air quality in Hoan Kiem district. This model can be used as a decision support tool for local authorities and as an information tool for the general public: thanks to its output on a tangible interface, people can interact with the simulation at public venues and explore various scenarios. Although more accurate data and realistic diffusion models are still lacking and will need further research in the future, the simulation is alreay able to reflect traffic and air pollution peaks during rush hours quite realistically.
IEEE
2020
text
https://www.documentation.ird.fr/hor/fdi:010084422
oai:ird.fr:fdi:010084422
Pham Minh Duc, Chapuis Kevin, Drogoul Alexis, Gaudou Benoît, Grignard A., Marilleau Nicolas, Nguyen-Huu Tri. HoanKiemAir : simulating impacts of urban management practices on traffic and air pollution using a tangible agent-based model. In : . 2020 RIVF International Conference on Computing and Communication Technologies (RIVF) IEEE, 2020, 1-7 International Conference on Computing and Communication Technologies, HO CHI MINH CITY (VNM), 2020/10/14-15
EN
VIET NAM
HANOI
Proceedings of the first Vietnamese-French joint conference on applications of mathematics to ecology, bio-economics, epidemiology and health care : Hanoi and Tuanchau, Vietnam, december 12-15, 2016
Doanh, N. N.
/Nguyen-Huu, Tri
2018
text
https://www.documentation.ird.fr/hor/fdi:010074405
oai:ird.fr:fdi:010074405
Doanh N. N., Nguyen-Huu Tri. Proceedings of the first Vietnamese-French joint conference on applications of mathematics to ecology, bio-economics, epidemiology and health care : Hanoi and Tuanchau, Vietnam, december 12-15, 2016. 2018, 66 (4), 255-256
EN
Can overexploited fisheries recover by self-organization ? Reallocation of fishing effort as an emergent form of governance
/Brochier, Timothée
/Auger, Pierre
Thiao, D.
Bah, A.
Ly, S.
/Nguyen-Huu, Tri
/Brehmer, Patrice
Small scale fisheries
Self-regulation
Fishing effort
Bio-economic model
Migration of fishermen
West-Africa
Owing to high costs and difficulties in implement control, fisheries are less regulated than terrestrial activities. In areas of weak governance, self-regulation is often the rule. Understanding the underlying bio-economic mechanisms that drive such fishery systems is crucial for decision making on how to support real fishermen communities. Fishing effort reallocation occurs when economic yield drops, suggesting a feedback between fishermen's mobility and local overexploitation. The nature of this feedback is addressed here by using a bio-economic modelling approach applied to a Senegalese fishery. The white grouper is a highly valued commercial fish that has suffered intense exploitation in Senegal and was predicted to collapse due to a lack of fishery regulation combined with high demand. Surprisingly, our analysis of landings and associated price variability suggests that a slow recovery of this fishery is now underway. Motivated by this finding, two models were implemented that account for artisanal fishermen's mobility and variable prices. Both models provided the same insight: fishing effort mobility combined with variable fish prices induced a shift from local overexploitation to sub-regional sustainable exploitation. Considering that fishing effort mobility has steeply increased in recent years, this mechanism might have significantly contributed to the recent observed trends in prices and landings for this fishery. More generally, these bio-economic models suggest that spatial reallocation of fishing effort acts as emergent governance in under regulated areas that allows, in some cases, the recovery of an overexploited species.
2018
text
https://www.documentation.ird.fr/hor/fdi:010073796
oai:ird.fr:fdi:010073796
Brochier Timothée, Auger Pierre, Thiao D., Bah A., Ly S., Nguyen-Huu Tri, Brehmer Patrice. Can overexploited fisheries recover by self-organization ? Reallocation of fishing effort as an emergent form of governance. 2018, 95, 46-56
EN
AFRIQUE DE L'OUEST
SENEGAL
ODD+2D: An ODD Based Protocol for Mapping Data to Empirical ABMs
Laatabi, A.
/Marilleau, Nicolas
/Nguyen-Huu, Tri
Hbid, H.
Babram, M. A.
Empirical Agent-Based Models
ODD protocol
ODD+2D
Mapping
Data analysis
Social simulation
The quantity of data and processes used in modeling projects has been dramatically increasing in recent years due to the progress in computation capability and to the popularity of new approaches such as open data. Modelers face an increasing difficulty in analyzing and modeling complex systems that consist of many heterogeneous entities. Adapting existing models is relevant to avoid dealing with the complexity of writing and studying a new model from scratch. ODD (Overview, Design concepts, Details) protocol has emerged as a solution to document Agent-Based Models (ABMs). It appears to be a convenient solution to address significant problems such as comprehension, replication, and dissemination. However, it lacks a standard that formalizes the use of data in empirical models. This paper tackles this issue by proposing a set of rules that outline the use of empirical data inside an ABM. We call this new protocol ODD+2D (ODD+Decision + Data). ODD+2D integrates a mapping diagramcalled DAMap (Data to Agent Mapping). This mapping model formalizes howdata are processed and mapped to agent-based models. In this paper, we focus on the architecture of ODD+2D, and we illustrate it with a residential mobility model in Marrakesh.
2018
text
https://www.documentation.ird.fr/hor/fdi:010073670
oai:ird.fr:fdi:010073670
Laatabi A., Marilleau Nicolas, Nguyen-Huu Tri, Hbid H., Babram M. A.. ODD+2D: An ODD Based Protocol for Mapping Data to Empirical ABMs. 2018, 21 (2), art. 9 [24 p.]
EN
MAROC
MARRAKECH
Uncertainty in empirical estimates of marine larval connectivity
/Kaplan, David
Cuif, M.
/Fauvelot, Cécile
/Vigliola, Laurent
/Nguyen-Huu, Tri
Tiavouane, J.
/Lett, Christophe
connectivity
larval dispersal
parentage analysis
self-recruitment
transgenerational marking
Despite major advances in our capacity to measure marine larval connectivity (i.e. the pattern of transport of marine larvae from spawning to settlement sites) and the importance of these measurements for ecological and management questions, uncertainty in experimental estimates of marine larval connectivity has been given little attention. We review potential uncertainty sources in empirical larval connectivity studies and develop Bayesian statistical methods for estimating these uncertainties based on standard techniques in the mark-recapture and genetics literature. These methods are implemented in an existing R package for working with connectivity data, ConnMatTools, and applied to a number of published connectivity estimates. We find that the small sample size of collected settlers at destination sites is a dominant source of uncertainty in connectivity estimates in many published results. For example, widths of 95% CIs for relative connectivity, the value of which is necessarily between 0 and 1, exceeded 0.5 for many published connectivity results, complicating using individual results to conclude that marine populations are relatively closed or open. This "small sample size" uncertainty is significant even for studies with near-exhaustive sampling of spawners and settlers. Though largely ignored in the literature, the magnitude of this uncertainty is straightforward to assess. Better accountability of this and other uncertainties is needed in the future so that marine larval connectivity studies can fulfill their promises of providing important ecological insights and informing management questions (e.g. related to marine protected area network design, and stock structure of exploited organisms). In addition to using the statistical methods developed here, future studies should consistently evaluate and report a small number of critical factors, such as the exhaustivity of spawner and settler sampling, and the mating structure of target species in genetic studies.
2017
text
https://www.documentation.ird.fr/hor/fdi:010070836
oai:ird.fr:fdi:010070836
Kaplan David, Cuif M., Fauvelot Cécile, Vigliola Laurent, Nguyen-Huu Tri, Tiavouane J., Lett Christophe. Uncertainty in empirical estimates of marine larval connectivity. 2017, 74 (6), 1723-1734
EN
Formalizing data to agent model mapping using MOF : application to a model of residential mobility in Marrakesh
Agent and multi-agent systems : technology and applications
Laatabi, A.
/Marilleau, Nicolas
/Nguyen-Huu, Tri
Hbid, H.
Babram, M. A.
Modeling and simulating the world with agent-based models is a one of the key disciplines that emerge today in the computing area, with the development of power calculation machines and the availability of huge amount of data. Many methodologies have been established to guide the elaboration of different models, but few ones have focused on linking data to model. In this paper, we give a formalized mapping between data and multi-agent components (DAMap: Data to Agent Mapping), as a first step in the process of standardizing the development of a simulation model from raw data. Then we apply it to an household decision-making process in the city of Marrakesh.
Springer
Jezic, G. (ed.)
Chen-Burger, Y.H.J. (ed.)
Howlett, R.J. (ed.)
Jain, L.C. (ed.)
2016
text
https://www.documentation.ird.fr/hor/fdi:010072196
oai:ird.fr:fdi:010072196
Laatabi A., Marilleau Nicolas, Nguyen-Huu Tri, Hbid H., Babram M. A.. Formalizing data to agent model mapping using MOF : application to a model of residential mobility in Marrakesh. In : Jezic G. (ed.), Chen-Burger Y.H.J. (ed.), Howlett R.J. (ed.), Jain L.C. (ed.), . Agent and multi-agent systems : technology and applications Springer, ; 58). 2016, 107-117 KES-AMSTA : Colloque International KES, 10., Puerto de la Cruz (SPA), 2016/06/15-17
EN
MAROC
MARRAKECH
Multi-site fishery models with price variation depending on demand and supply [résumé]
Book of abstract international conference ICAWA 2014 : the AWA project : ecosystem approach to the management of fisheries and the marine environment in West African waters
/Auger, Pierre
Ly, S.
Mansal, F.
/Nguyen Huu, Tri
SRFC/CSRP
IRD
/Brehmer, Patrice (ed.)
Diop, H. (ed.)
Gomez, M.M. (collab.)
Diogoul, N. (collab.)
Koutob, V. (collab.)
Brandt, P. (collab.)
Sow, B.A. (collab.)
Lazar, A. (collab.)
Capet, X. (collab.)
Fock, H. (collab.)
Santos, C.F. (collab.)
/Machu, Eric (collab.)
Diadihou, H. (collab.)
/Jouffre, Didier (collab.)
Diallo, I. (collab.)
Schmidt, J. (collab.)
Gaye, A. (collab.)
Ould Taleb Sidi, M. (collab.)
/Gouriou, Yves (collab.)
/Almar, Rafael (collab.)
Sall, M. (collab.)
Duval Diop, D. (collab.)
Thiow, M. (collab.)
Wanless, R. (collab.)
Gonzales-Solis Bou, J. (collab.)
Ly, I. (collab.)
Beye Traoré, D. (collab.)
/Bonnin, Marie (collab.)
Ekau, W. (collab.)
2015
text
https://www.documentation.ird.fr/hor/fdi:010068010
oai:ird.fr:fdi:010068010
Auger Pierre, Ly S., Mansal F., Nguyen Huu Tri, . Multi-site fishery models with price variation depending on demand and supply [résumé]. In : Brehmer Patrice (ed.), Diop H. (ed.), Gomez M.M. (collab.), Diogoul N. (collab.), Koutob V. (collab.), Brandt P. (collab.), Sow B.A. (collab.), Lazar A. (collab.), Capet X. (collab.), Fock H. (collab.), Santos C.F. (collab.), Machu Eric (collab.), Diadihou H. (collab.), Jouffre Didier (collab.), Diallo I. (collab.), Schmidt J. (collab.), Gaye A. (collab.), Ould Taleb Sidi M. (collab.), Gouriou Yves (collab.), Almar Rafael (collab.), Sall M. (collab.), Duval Diop D. (collab.), Thiow M. (collab.), Wanless R. (collab.), Gonzales-Solis Bou J. (collab.), Ly I. (collab.), Beye Traoré D. (collab.), Bonnin Marie (collab.), Ekau W. (collab.), . Book of abstract international conference ICAWA 2014 : the AWA project : ecosystem approach to the management of fisheries and the marine environment in West African waters SRFC/CSRP ; IRD, 2015, 44 International Conference AWA (ICAWA), 1., Dakar (SEN), 2014/12/09-11
EN
AFRIQUE DE L'OUEST
SENEGAL
ATLANTIQUE
A mathematical model of a fishery with variable market price : sustainable fishery/over-exploitation
Mansal, F.
/Nguyen-Huu, Tri
/Auger, Pierre
Balde, M.
Dynamical systems
Fishery
Variable price
Market price equation
Demand function
Equilibrium
Stability
Sustainable
exploitation/overexploitation
We present a mathematical bioeconomic model of a fishery with a variable price. The model describes the time evolution of the resource, the fishing effort and the price which is assumed to vary with respect to supply and demand. The supply is the instantaneous catch while the demand function is assumed to be a monotone decreasing function of price. We show that a generic market price equation (MPE) can be derived and has to be solved to calculate non trivial equilibria of the model. This MPE can have 1, 2 or 3 equilibria. We perform the analysis of local and global stability of equilibria. The MPE is extended to two cases: an age-structured fish population and a fishery with storage of the resource.
2014
text
https://www.documentation.ird.fr/hor/fdi:010062478
oai:ird.fr:fdi:010062478
Mansal F., Nguyen-Huu Tri, Auger Pierre, Balde M.. A mathematical model of a fishery with variable market price : sustainable fishery/over-exploitation. 2014, 62 (3), 305-323
EN
A model of a multi-site fishery with variable price : from over-exploitation to sustainable fisheries
Ly, S.
Mansal, F.
Balde, M.
/Nguyen Huu, Tri
/Auger, Pierre
dynamical system
multi-site fishery
variable price
demand function
equilibrium
stability
optimum capture
We present a mathematical model of a fishery on several sites with a variable price. The model takes into account the evolution during the time of the resource, fishes and boats movements between the different it sites, fishing effort and price that varies with respect to supply and demand. We suppose that boats and fishes movements as well as prices variations occur at a fast time scale. NW use methods of aggregation of variables in order to reduce the number of variables and we derive a reduced model governing two global variables, respectively the biomass of the resource and the fishing effort of the whole fishery. We look for the existence of equilibria of the aggregated model. We show that the aggregated model can have I, 2 or 3 non trivial equilibria. We show that a variation of the total number of sites can induce a switch from over-exploitation to sustainable fisheries.
2013
text
https://www.documentation.ird.fr/hor/fdi:010061333
oai:ird.fr:fdi:010061333
Ly S., Mansal F., Balde M., Nguyen Huu Tri, Auger Pierre. A model of a multi-site fishery with variable price : from over-exploitation to sustainable fisheries. 2013, 8 (6), 130-142
EN
Effects of refuges and density dependent dispersal on interspecific competition dynamics
Nguyen-Ngoc, D.
/Nguyen-Huu, Tri
/Auger, Pierre
COMPETITION INTERSPECIFIQUE
MODELE MATHEMATIQUE
ANALYSE STATISTIQUE
DISPERSION
DENSITE DE POPULATION
2012
text
https://www.documentation.ird.fr/hor/fdi:010056269
oai:ird.fr:fdi:010056269
Nguyen-Ngoc D., Nguyen-Huu Tri, Auger Pierre. Effects of refuges and density dependent dispersal on interspecific competition dynamics. 2012, 22 (2), 11
EN
Modelling herbivore population dynamics in the Amboseli National Park, Kenya : application of spatial aggregation of variables to derive a master model
Mose, V. N.
/Nguyen-Huu, Tri
/Auger, Pierre
Western, D.
Large parks
Herbivorous
Competition model
Aggregation of variables
The recent expansion of human activities such as agriculture has continuously threatened to block wildlife migration corridors that connect Amboseli National Park (Kenya) to surrounding ecosystems. We study the impact of blocked corridors on herbivore populations using a spatial mathematical model that describes the movements and population dynamics of selected species (zebra, wildebeest and Grant's gazelle) based on resource availability. Aggregation methods are used to reduce the complexity of the model which uses actual parameters calibrated from long term data collected in the area for over three decades. The model suggests the need to maintain these connections to sustain species diversity. Our results show that blocked migration corridors lead to competitive exclusion where only one species survives. However, a possible mechanism of maintenance of biodiversity in the area could be due to an exchange of animals between the park and surrounding ecosystems, when the oscillations of species densities in the ecosystems are out of phase compared to each other and to those within the park.
2012
text
https://www.documentation.ird.fr/hor/fdi:010055926
oai:ird.fr:fdi:010055926
Mose V. N., Nguyen-Huu Tri, Auger Pierre, Western D.. Modelling herbivore population dynamics in the Amboseli National Park, Kenya : application of spatial aggregation of variables to derive a master model. 2012, 10 (SI), 42-51
EN
Effects of fast density dependent dispersal on pre-emptive competition dynamics
Doanh, N. N.
/Nguyen-Huu, Tri
/Auger, Pierre
Competition model
Aggregation of variables
Time scales
Density-dependent dispersal
Emergence
The aim of this work is to investigate the effect of density-dependent dispersal on the outcome of competition in a heterogeneous environment. We present a classical spatial interspecific competition model with two patches connected by fast dispersal. We assume local pre-emptive competition, i.e. on each isolated patch, the species having the largest initial density would exclude the other one. We assume that individuals of species 1 disperse at constant dispersal rates, while species 2 dispersal is density dependent. Species 2 individuals are more likely to disperse when there are many species 1 competitors in a patch. We investigate if a dispersal strategy that aims at avoiding its competitor can be beneficial. Dispersal between patches is assumed to be faster than local population dynamics on each patch. We take advantage of these time scales in order to reduce the complete model into an aggregated model governing total densities of both species at a slow time scale. The analysis of this global model shows that using a density dependent strategy for dispersal is beneficial for species 2 in the sense that it prevents its own extinction and even it allows species 2 to exclude species 1 under some conditions.
2012
text
https://www.documentation.ird.fr/hor/fdi:010055930
oai:ird.fr:fdi:010055930
Doanh N. N., Nguyen-Huu Tri, Auger Pierre. Effects of fast density dependent dispersal on pre-emptive competition dynamics. 2012, 10 (SI), 26-33
EN
Study of a virus-bacteria interaction model in a chemostat : application of geometrical singular perturbation theory
Poggiale, J. C.
/Auger, Pierre
Cordoleani, F.
/Nguyen-Huu, Tri
invariant manifold
reduction
singular perturbation
virus-bacteria interaction
This paper provides a mathematical analysis of a virus-marine bacteria interaction model. The model is a simplified case of the model published and used by Middelboe (Middelboe, M. 2000 Microb. Ecol. 40, 114-124). It takes account of the virus, the susceptible bacteria, the infected bacteria and the substrate in a chemostat. We show that the numerical values of the parameters given by Middelboe allow two different time scales to be considered. We then use the geometrical singular perturbation theory to study the model. We show that there are two invariant submanifolds of dimension two in the four-dimensional phase space and that these manifolds cross themselves on the boundary of the domain of biological relevance. We then perform a rescaling to understand the dynamics in the vicinity of the intersection of the manifolds. Our results are discussed in the marine ecological context.
2009
text
https://www.documentation.ird.fr/hor/fdi:010048367
oai:ird.fr:fdi:010048367
Poggiale J. C., Auger Pierre, Cordoleani F., Nguyen-Huu Tri. Study of a virus-bacteria interaction model in a chemostat : application of geometrical singular perturbation theory. 2009, 367 (1908), 4685-4697
EN
Applications de méthodes d'agrégation de variables à l'analyse de modèles spatiaux de dynamique des populations
2007 Conference in Honor of Claude Lobry
/Nguyen-Huu, Tri
/Auger, Pierre
DYNAMIQUE DE POPULATION
RELATION HOTE PARASITE
MODELISATION
MODELE MATHEMATIQUE
ANALYSE MULTIVARIABLE
Les modèles de dynamique de populations peuvent prendre en compte un nombre important de paramètres et de variables, ce qui les rend difficiles à analyser. Lorsqu'il existe des processus associés à deux échelles de temps différentes, une lente et une rapide, les méthodes d'agrégation de variables permettent de construire un modèle simplifié qui comporte un nombre plus faible de variables. Elles permettent ainsi d'analyser et de décrire un système de manière globale. Nous présentons ces méthodes dans le cas de modèles discrets, puis nous illustrons leur utilisation à l'aide de modèles hôte-parasitoïdes spatialisés.
Teuw Niane, M. (ed.)
Sallet, G. (ed.)
Sari, T. (ed.)
Touré, H. (ed.)
2008
text
https://www.documentation.ird.fr/hor/fdi:010065708
oai:ird.fr:fdi:010065708
Nguyen-Huu Tri, Auger Pierre, . Applications de méthodes d'agrégation de variables à l'analyse de modèles spatiaux de dynamique des populations. In : Teuw Niane M. (ed.), Sallet G. (ed.), Sari T. (ed.), Touré H. (ed.), . 2007 Conference in Honor of Claude Lobry 2008, 9 (No spécial Claude Lobry), 195-210 International Conference in Honor of Claude Lobry, Saint-Louis du Sénégal (SEN), 2007/09/14-17
FR
Aggregation of variables and applications to population dynamics
/Auger, Pierre
de la Parra, R. B.
Poggiale, J. C.
Sanchez, E.
/Nguyen-Huu, Tri
2008
text
https://www.documentation.ird.fr/hor/PAR00005739
oai:ird.fr:PAR00005739
Auger Pierre, de la Parra R. B., Poggiale J. C., Sanchez E., Nguyen-Huu Tri. Aggregation of variables and applications to population dynamics. 2008, 1936, 209-263
EN
Predator density-dependent prey dispersal in a patchy environment with a refuge for the prey
Duc, K. D.
/Auger, Pierre
/Nguyen-Huu, Tri
In this article, we examine a two-patch predator-prey model which incorporates a refuge for the prey. We suppose that prey migration is dependent on predator density, according to a general function. We consider two different time scales in the dynamics of the model, a fast one describing patch to patch migration, and a slow one involving local prey and predator interaction. We take advantage of the time scales to reduce the dimension of the model by use of methods of aggregation of variables, and thereby examine the effect of predator density-dependent migration of prey on the stability of the predator-prey system. We establish a simple criterion of viability, namely, the existence of a positive and globally stable equilibrium, and show that density dependence has beneficial effects on both species by providing larger equilibrium densities.
2008
text
https://www.documentation.ird.fr/hor/fdi:010071081
oai:ird.fr:fdi:010071081
Duc K. D., Auger Pierre, Nguyen-Huu Tri. Predator density-dependent prey dispersal in a patchy environment with a refuge for the prey. 2008, 104 (5-6), 180-184
EN
Spatial synchrony in host-parasitoid models using aggregation of variables
/Nguyen-Huu, Tri
/Lett, Christophe
/Auger, Pierre
Poggiale, J.C.
2006
text
https://www.documentation.ird.fr/hor/PAR00005387
oai:ird.fr:PAR00005387
Nguyen-Huu Tri, Lett Christophe, Auger Pierre, Poggiale J.C.. Spatial synchrony in host-parasitoid models using aggregation of variables. 2006, 203 (2), 204-221
EN