Multi-agents Modeling and Simulation of the Spread of Tuberculosis in the City of Ngaoundéré (Cameroon)

In this paper, a model based on Multi-Agent Systems (MAS) of the spread of tuberculosis in the city of Ngaoundéré is proposed. After studying the behavior of the population and treatment using the software "OpenJUMP" of the satellite image of the city of Ngaoundéré, a multi-agent modeling of the population including individual activities, contraction and evolution of tuberculosis is made. This modeling followed the Gaia approach and used the modeling language AUML. The satellite image was processed in the integrated simulation platform GAMA and simulations were made. The simulation results show that in the absence of treatment, the rate of spread of tuberculosis in the city of Ngaoundéré, denoted T0 strongly depends on the behavior of individuals, the quantity of Koch Bacillus (BK) released by a sick individual, the life of a BK in the air. The analysis of T0 shows that there is a threshold beyond which the disease is endemic and below which it disappears.

An Architecture for Misconfiguration Patching of Web Services: A Case Study of Apache Server

Services are usually left configured by default and therefore subjects to vulnerabilities because they are not security enforced. Web services are so popular that they are targets of attacks to intrusions related to vulnerabilities discovered by attackers. This work proposes an architecture for patching Web service misconfigurations related to existing vulnerabilities. The approach underlying this architecture first retrieves and structures anti-vulnerability measures published by the official service manufacturers. Second, it evaluates the risk level using Common Vulnerability Scoring System (CVSS) on the current state of configurations. The proposed approach has been applied on Apache server on four vulnerabilities: version discovery, XSS, SQL injection and deny of service. Experimental results on a vulnerable environment demonstrate that the proposed approach considerably reduces vulnerabilities compared to similar solutions

Un modèle stochastique pour la propagation du VIH/SIDAUne approche individuelle-centrée

Le but de cette thèse est de mettre en place un modèle informatique de simulation stochastique et individucentré qui simule la dynamique démo-épidémiologique du VIH/SIDA dans une population hétérosexuelle à régime matrimoniale polygamique incluant des prostituées et leurs clients. Chaque individu admet un certain nombre de propriétés qui donnent à tout instant des renseignements sur son comportement sexuel et son infectivité, sa fécondabilité ou qui permettent de l identifier. Ce modèle se veut beaucoup plus réaliste que les modèles existants et intégre des paramètres démographiques et épidémiologiques qui peuvent avoir un effet sur la dynamique démo-épidémiologique. Son côté individu-centré donne la possibilité d introduire de l hétérogénéité sur chaque propriété individuelle et en plus facilite son extension. La durée de l abstinence sexuelle et des liaisons de longue durée ont un faible effet sur la propagation de la maladie. La probabilité de transmission maximale à la fin de la séroconversion et le nombre mensuel de visites d un client chez les prostituée ont un effet important sur la propagation. Le modèle montre par exemple que si chaque client visite en moyenne une prostituée par mois alors les taux de transmission sont insuffisants pour que l épidémie soit généralisée. Si ce nombre passe à 2 visites par mois alors au moins 80% de prostituées, 40% de clients et 14% des adultes deviennent infectés. Avec une probabilité de transmission maximale égale à 0.018 l épidémie disparaît même avec 2 visites de clients par mois. Nos résultats montrent l importance des prostituées et de la probabilité de transmission du VIH/SIDA par voie hétérosexuelle.The purpose of this work is to develop an individual-based model of the population dynamics of HIV/AIDS in a heterosexual population that includes polygamous and clients-sex worker relationships. Each individual has a certain number of attributes concerning his/her sexual behaviour, infectivity, and fertility. The model attempts to be more realistic than existing models by incorporating a number of relevant demoepidemiologic parameters. The model incorporates various forms of heterogeneity and can easily be extended. The duration between partnerships and the duration of long-term partnerships have a small effect on the spread of the disease. The peak probability of transmission during the early high infectivity period and the monthly number of prostitute visits have a large effect on the spread. If each client visits one prostitute per month the disease cannot spread. If this number doubles to two, then 80% of prostitutes, 40% of clients, and 14% of the population at large become infected. With a maximum probability of transmission of 0.018, the disease disappears, even with two visits per month. Our work highlights the importance of the probability of transmission and of the client-sex worker relationship.PAU-BU Sciences (644452103) / SudocSudocFranceF

Modélisation et simulation à base d'agents de la propagation d'une parasitose végétale le gui

Mistletoe is the common name of tree species of seagrass and orchards hemiparasites of the family Loranthaceae. Although possessing therapeutic virtues, mistletoes cause significant damages to their hosts thereby causing production losses. Loranthaceae dispersal mechanisms are still poorly understood. The purpose of this study is to identify and rank the factors that influence the spread of these parasites. In this article we build a multi-agent model for the spread of mistletoe in orchards. This model was built according to the modeling approach of multi-agent systems (MAS) GAIA Version 2. After an implementation of this system using the Java simulation library MASON. We perform sensitivity analysis of outputs of the simulation. It shows that: the rate of infection increases with the availability of mistletoe berries, attendance of the birds and the amount of berries produced by each plant; but it strongly decreases with the competition factor; infestation intensity in turn, increases with the age of hosts. Our study reveals that a dispersion of mistletoe on long distances is attributable to endozoochores birds, while epizoochores birds act locally"Gui d'Afrique" est la désignation commune des phanérogames hémiparasites des essences ligneuses et de vergers de la famille des Loranthaceae. Bien que possédant les vertus thérapeu-tiques, les guis causent des dégâts importants à leurs hôtes occasionnant de ce fait des pertes de production. Les mécanismes de dispersion des loranthaceae sont encore peu connus. Le but de cette étude est d'identifier et classer les facteurs qui influencent la dissémination de ces parasites. Dans cet article, un modèle multi-agents de la propagation du gui dans une plantation d'arbres fruitiers est construit. Ce modèle a été construit suivant la démarche de modélisation des systèmes multi-agents(SMA) GAIA Version 2. Après une implémentation de ce système en utilisant la bibliothèque de simulation des SMA MASON, une analyse de sensibilité des sorties de ce modèle a été faite. Il en ressort que: le taux d'infestation croit avec la disponibilité des baies de gui, la fréquentation des oiseaux et la quantité de baies produites par chaque plant; par contre, il décroit fortement avec le facteur de compétition; l'intensité d'infestation quant à elle, croit avec l'âge des hôtes. Notre étude révèle qu'une dispersion de gui à grande distance n'est imputable qu'aux oiseaux endozoochores alors que les oiseaux épizoochores agissent à l'échelle locale

Management of Hybrid Renewable Energy Systems Using Differential Hybrid Petri Nets

Investigations in this paper concern management of Hybrid Renewable Energy systems. To achieve it, a supervisory system based on hybrid systems concept is designed, in order to ensure power flow between energy generators (solar panel and pico-hydroelectric), batteries and load. Differential Hybrid Petri Net is used to model the proposed supervisory and simulations are made in Matlab environment.Results obtained present a good performance criteria Loss of Power Supply Probability, and this show the effectiveness of our approach in the coordination of HREs components during the energy sharing process by reducing load shedding in microgrid system

Development of a Human-Agent Interaction System including Norm and Emotion in an Evacuation Situation (Student Abstract)

Agent-based modeling and simulation can provide a powerful test environment for crisis management scenarios. Human agent interaction has limitations in representing norms issued by an agent to a human agent that has emotions. In this study, we present an approach to the interaction between a virtual normative agent and a human agent in an evacuation scenario. Through simulation comparisons, it is shown that the method used in this study can more fully simulate the real-life out come of an emergency situation and also improves the au thenticity of the agent interaction

A critical review of the use of holonic paradigm in traffic and transportation systems

International audienceThe paper presents a critical review of the use of holonic paradigm in order to model and simulate traffic and transportation systems. After an introduction presenting the principles of this paradigm as well as its frameworks and concepts, the paper surveys existing works using the holonic paradigm for traffic and transportation applications. This is followed by a detailed analysis of the results of the survey. In particular, the relevance, the design approaches and the holonification orientation methodologies are investigated. Finally, based on this extensive review, open issues of holonic paradigm in modeling and simulation of traffic and transportation models are highlighted.Holonic multi-agent system; Holonic manufacturing system; Multilevel; Traffic; Transportatio

Towards a multi-agent model to prevent damage caused by cocoa mirids to cocoa pods

Co-localisées avec la Plate-Forme Intelligence Artificielle (PFIA 2019)International audienceAgriculture in general and cocoa farm in particular is one of the primary sources of income for several African countries. Although quite useful for the development of Africa, cocoa production is faced with several challenges like the diseases of cocoa trees. Mirid (Sahlbergella singularis) is the worst pest affecting cocoa production across west Africa causing 30% to 40% of damage on cocoa production. It is difficult to control the mirids’ population and its impact on the cacao production. Related works on mirids studied the mirids population as a macroscopic entity without considering local interactions of individual mirids. These models did not consider the behaviours and the environment of mirids which are essential due to their complexity. To overcome these drawbacks, this paper proposes an agent-based model of mirids considering the individual interactions of mirids within the environment. The proposed model consists of agents representing the mirids through their life cycle in cocoa farm environments. It is based on the biological and ecological partial knowledge found in the literature, and is built according to the GAIA methodology. The main assets of this model are the reproduction of the dynamics of the mirids on a cocoa pod and damage caused by them at the micro level for human users (entomologists, agricultural engineers, farmers and decision makers) to thoroughly understand the phenomena and the emergent properties outcomes.L’agriculture en général et la culture du cacao en particulier est l’une des principales sources de revenus de plusieurs pays africains. Cependant, la production du cacao est confrontée à plusieurs défis tels que les maladies et l’attaque des insectes nuisibles. Les mirides (Sahlbergella singularis) sont les insectes les plus préjudiciables à la culture du cacao en Afrique. Avec 30 à 40 % de dommages sur la production, il est difficile de contrôler la population des mirides ainsi que son impact sur la production de cacao. Les travaux précédents sur les mirides, étudient la population de cet insecte selon le point de vue macroscopique sans tenir compte des interactions locales entre les mirides. Ces modèles ne prennent pas en compte les comportements individuels des mirides et leurs interactions avec l’environnement qui sont essentiels en raison de leurs complexités. Pour remédier à ces insuffisances, le présent article propose un modèle de mirides à base d’agents prenant en compte les interactions individuelles des mirides dans leur environnement. Le modéle proposé est constitué d’agents représentant le cycle de vie du miride sur une cabosse de cacao. Il est basé sur les connaissances biologiques et écologiques du miride, et est construit selon la méthodologie GAIA. Ces modèles ainsi que leurs implémentations sont destinés à des utilisateurs tels que les entomologistes, les ingénieurs agronomes, les agriculteurs et les décideurs. Cela leur permettra de mieux comprendre les phénomènes émergents dues aux mirides ainsi que leurs propriétés