Teses / dissertações sobre o tema "Modélisation des catastrophes"
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Enjolras, Geoffroy. "De l'assurabilité des catastrophes naturelles : Modélisation et application à l'assurance récolte". Montpellier 1, 2008. http://www.theses.fr/2008MON10020.
Texto completo da fonteNatural catastrophes are complex hazards which generate major losses, especially in the agricultural sector. As a result, their insurability is limited and the insurance market is incomplete. Facing these limitations, we develop an innovative combination of insurance and financial instruments adapted to the coverage of the different aspects of natural risks. Our application focuses on crop insurance which is being reformed in France. The thesis is organized in four main parts: the first part presents a survey of literature on catastrophic risks and the potential insurance and financial instruments. The second part exposes a case study on flood risk management at the river-basin scale. In a third part, we develop a theoretical model that tends to offer an optimal coverage against catastrophic risk. The fourth part consists in an empirical validation of the model performing regressions and a full set of tests
Nikolkina, Irina. "Modélisation des écoulements de gravité et des ondes longues : application à l'évaluation des risques de catastrophes naturelles dans les Antilles françaises". Thesis, Antilles-Guyane, 2011. http://www.theses.fr/2011AGUY0435/document.
Texto completo da fonteThe dissertation is devoted to research in the field of marine natural hazards (tsunamis, storm surges) in the French West Indies, using analytical and numerical models of fluid mechanics. Emphasis is placed on the development of models of landslide motion and generated tsunami waves. The simple "solid block" model is used to evaluate the characteristics of pyroclastic flow Soufriere Hills volcano (Montserrat). The "fluid model" of a landslide (so called Savage-Hutter model) is studied analytically; within this model a new family of exact solutions that describe the motion of nonlinear gravity flow in a valley or underwater canyon is found: nonlinear Riemann wave, dan break problem, self-similar solutions (M - wave and parabolic cap). In the framework of the linear shallow water theory the process of generation of tsunami waves by landslides of variable volume moving with variable velocity above the basin of variable depth is studied. For the specific bottom profile ("reflectionless" one) the resonant phenomena is investigated in the basin of variable depth. Numerical methods are used to analyze marine hazards: historical (storm surges, caused by Cyclone LILI in 2002; volcanic tsunami 2003 on Montserrat) and possible events (possible tsunami of the coast of Martinique). Various data on marine natural disasters are obtained during field surveys (volcanic tsunami in 2003, stonn surges caused by Hurricane Dean in 2007). Designed catalogs of tsunamis and storm surges are created based on results of numerical modeling and field studies; some statistical analysis is perfomed
Ardon, Jean. "Modélisation probabiliste de la dépendance spatiale et temporelle appliquée à l’étude du péril sécheresse dans le cadre du régime français d’indemnisation des catastrophes naturelles". Thesis, La Rochelle, 2014. http://www.theses.fr/2014LAROS002.
Texto completo da fonteThis work was performed at CCR, a French reinsurance company, within the studies that are conducted to model natural disasters, and particularly the drought hazard. Drought is the word used to denote the shrink-swell clay phenomenon that damages individual houses. These researches are related to an internal model that estimates the annual cost of a drought. This model crosses insurance data and soil moisture data to evaluate the cost of a occured event. CCR wants this model to be improved towards a probabilistic version by conceiving a generator of drought events that have to be realistic, although they are fictive. This generator will allow the estimation of the probability distribution of the drought cost. In order to conceive a fictive event generator for CCR’s drought model, mathematical tools have been used to model dependence between spatio-temporal random variables. The chosen method consists of studying and modeling separately spatial dependence and temporal dependence. Temporal dependence is modelized with time series models such as classical decomposition and autoregressive processes. Spatial dependence is modelized with kriging and copula theory. Spatial random noise is generated with a copula and then time series models are applied to rebuild original process. Kriging is used when generated data need to be interpolated, for example when data are generated only on a subset of the main grid. Results of the generator exploitation are given. They will be used by CCR for provisionning and pricing. These results will also be used for the estimation of the two-hundred-year cost of natural disasters within the new European Solvency II Directive
Mao, Gwladys. "Estimation des coûts économiques des inondations par des approches de type physique sur exposition". Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1192/document.
Texto completo da fonteThis research was conducted within the framework of the Caisse Centrale de Réassurance's (CCR) R&D objective - to widen the scope of impacts estimated by its flood impact model. In chapter one, we study the various impacts of a flood and their interdependencies in order to create a classification of impacts. This classification allows us to design the architecture of a global impact model built from linking specific impacts models where the outputs of one model are the inputs of the following one. This approach generates an estimation with a breakdown by type of impact. It also allows us to understand the domino effects from the direct damage to the macroeconomic impacts. In chapter two, we study models for car damages according to CCR's specifications. The requirements are: the model should be independent from other natural catastrophes and impacts estimations and it should be able to model both a specific event and the total annual load. Through this work we describe, implement, and identify issues with possible improvements of three modelling approaches: - a simple linear regression, CCR's presently used method, - a frequency x severity model associated to the extreme value theory, widely used in the insurance business sector, - a model that pairs a physical model with exposure through damage curves. CCR already uses this approach to estimate damage to buildings. Hence, we are using CCR's flood hazard model and develop an exposure model and a damage model specific to cars. CCR is in charge of the accounting management of the Agricultural National Risk Management Fund on behalf of the State. Hence, chapter three contains state of the art modeling solutions for this risk and description of the designed model and its implementation. A vulnerability model and a damage model specific to the agricultural risk are developed and paired with CCR's flood hazard model. The vulnerability model uses the Graphic Parcel Register database. The damage model is based on the damage curves developed by IRSTEA for the national think tank on flood cost-benefit analysis. Chapter four is a technical document that will allow CCR to continue the development of the global model. It presents a situational analysis of what has been done (cars and agricultural risks) and of ongoing works (business interruption due to direct damage). For the remaining impacts, it presents the modeling issues, a short research review and the conclusions reached in terms of modeling
Vongvixay, Amphone. "Mesure et analyse de la dynamique temporelle des flux solides dans les petits bassins versants : cas d'un bassin versant agricole en région d'élevage (basse-Normandie, France)". Phd thesis, Rennes, INSA, 2012. https://tel.archives-ouvertes.fr/tel-00688884.
Texto completo da fonteThe study was performed on the Moulinet and the Oir streams watershed, in Lower-Normandie region. The watershed area is 4,53 km2 and 87 km2 respectively. The main objectives are: 1) to measure and describe the temporal dynamics of the SSC, and 2) to relate these dynamics with the SS origins, the climatic determinants and the stream's order. The measuring of bed-load premises to determine the criterion for mobilizing particles from stream's bottom. The measurement of suspended sediment concentration (SSC) through the water turbidity was deepened. The SSC temporal dynamics was analyzed by different approaches: relationship SSC-discharge, statistic analysis and modeling with different time scale (year, month, season, day and flood scale). A first comparison of the hydrological response between the catchment of Moulinet and the Oir was presented
Ecoto, Dicka Geoffrey. "Modélisation et apprentissage machine learning appliqués à l'estimation des dommages consécutifs à la survenance d'un événement de sécheresse par retrait-gonflement des argiles dans le cadre du régime d'indemnisation des catastrophes naturelles français". Electronic Thesis or Diss., Université Paris Cité, 2023. http://www.theses.fr/2023UNIP7182.
Texto completo da fonteThis Ph.D. thesis is dedicated to forecasting the financial impact on insured properties in the event of drought, utilizing methods that merge statistics and machine learning. In this context, "drought" refers to the phenomenon of clay shrinkage and swelling that leads to damage to buildings. The task can be broken down into two sub-problems that we address separately. The first sub-problem focuses on predicting which municipalities will submit a request for the government declaration of natural disaster for a drought event. The second is dedicated to predicting the financial impact of drought events on insured properties located in municipalities that obtained the government declaration of natural disaster for a drought event. For the first sub-problem, we develop, study, and apply an original algorithm to predict requests for the government declaration of natural disaster. The algorithm benefits from two complementary formalizations of the task at hand, approached as both supervised classification and an optimal transport problem. The final predictions are obtained as a geometric mean of these two prediction types. Theoretically, the optimal transport plan can be obtained by applying the iPiano algorithm [Ochs et al., 2015], and we demonstrate that the assumptions underlying its analysis are met. The analysis of the predictions obtained confirms the algorithm's relevance. Regarding the second sub-problem, we develop, investigate, and apply an original aggregation algorithm, inspired by the Super Learner [van der Laan, 2007]. Two challenges must be considered. First, since drought events have only been covered by the French natural disaster compensation scheme since 1989, the number of drought events available for training our algorithm is limited, with each drought event associated with a large dataset. Second, temporal dependence is compounded by spatial dependence, primarily due to geographic and administrative proximity between French municipalities. Based on a dependency modeling using a dependency graph, the theoretical analysis reveals that the brevity of the time series can be compensated if spatial dependence is weak. Once again, the analysis of the predictions obtained underscores the relevance of our algorithm
Raillani, Hajar. "Disaster mοdelling and emergency facilities lοcatiοn under uncertainties : a case study οf the Μοrοccan relief supply chain". Electronic Thesis or Diss., Normandie, 2024. http://www.theses.fr/2024NORMIR10.
Texto completo da fonteDisaster modelling and facility location are critical aspects of disaster management that help to improve the effectiveness and efficiency of relief supply chains. However, the inherent uncertainties associated with disasters and relief supply chains can significantly impact the effectiveness of such models. To address this challenge, the thesis proposes the use of uncertainty quantification-based models and hidden Markov based models for disaster modelling in the context of the Moroccan relief supply chain. The thesis initiates by conceptualizing the Moroccan relief supply chain, comprehensively outlining its design, activities, and the various actors involved in the humanitarian process, then, a detailed analysis was conducted to highlight the strengths and weaknesses of the Moroccan relief supply chain. This involved a deep examination of uncertainty sources within the humanitarian process, to make a good understanding of challenges faced within the Moroccan relief supply chain and identify the specific requirements. Following this conceptual groundwork, the proposed models are then applied to a dedicated case study of the Moroccan relief supply chain. This practical application aims to validate the effectiveness of the uncertainty quantification-based models and hidden Markov-based models in a real-world scenario, providing valuable insights into their applicability, utility, and potential impact on the complex dynamics of the humanitarian field. The results demonstrate that the uncertainty quantification-based model and the hidden Markov based model can significantly improve the robustness and efficiency of the supply chain network in term of disaster prediction. The uncertainty quantification-based model enables to make prediction of the potential human impact of disasters and the most sensitive regions which can help in the evaluation of the robustness of the supply chain network under different scenarios, considering various sources of uncertainty, such as demand and uncertainties on documented data. On the other hand, the hidden Markov based model is used to predict the disaster behaviour in next occurrence, based on historical data and trends. This model provides important insights into the potential of HMMs in disaster management and humanitarian logistics and emphasize the importance of these models in protecting disasters impact, vulnerable populations and mitigating the effects of natural disasters in the future. The thesis aims also to identify the optimal facility locations and develop an efficient disaster response plan that can mitigate the impact of disasters, this stations will have for function the reception, control, support and the distribution of help in case of natural disasters (earthquakes, floods, torrential floods, locust invasions, drought, landslides ...) or man-made disasters (technological accidents, terrorist attacks, road accidents, pollution ...), through the integration of different actors in the Moroccan relief supply chain (Ministry of the Interior, Ministry of Planning of Moroccan Territories, the civil protection, military, NGOs ...) and by considering various sources of uncertainty, such as demand, transportation time, and supply disruptions. The optimal facility locations identified by the models provide a better coverage of the affected areas, thereby improving the speed and effectiveness of the disaster response plan. The thesis highlights the significance of incorporating uncertainty analysis in disaster modelling and provides insights into the relief supply chain management in Morocco. The findings of this thesis can be useful for policymakers and practitioners in disaster management to improve the effectiveness and efficiency of relief supply chains
Alaeddine, Houssein. "Un modèle d'optimisation spatio-temporel pour l'évacuation de la population exposée aux catastrophes naturelles : projet ACCELL : évaluation spatio-temporelle de l'ACCessibilité d'Enjeux localisés en situation d'inondation sur le bassin de la Loire". Thesis, Tours, 2014. http://www.theses.fr/2014TOUR1802/document.
Texto completo da fonteThe importance of managing an urban site threatened or affected by flooding requires the development of effective evacuation systems. An effective evacuation system has to take into account some constraints such as the transportation traffic which plays an important role as well as others such as the accessibility, necessary human resources and material equipment (vehicles, assembly points, etc...). The main objective of this work is to bring assistance to the technical services and brigade forces in terms of accessibility by providing itineraries with respect to rescue operations and the evacuation of people and goods.We consider the evacuation of a middle size area, exposed to a risk, and more precisely to a risk of flooding. In case of flooding event, the most of inhabitants will be evacuated by themselves, ie., using their personal vehicles. Considered case here, the flooding can be forecast in advance, and then the population has few days (2-4) to evacuate. Our aimis to build an evacuation plan, ie., fixing for each individual the date of departure and the path to reach the assembly point (also called shelter) associated. Evacuation plan must avoid congestion on the roads of evacuation network.Here, we present a spatio-temporal optimization model for the evacuation of the population exposed to natural disasters, and more particularly to a flood risk
Leebmann, Johannes. "Dreidimensionale Skizzen in Erweiterter Realität". Phd thesis, Université Louis Pasteur - Strasbourg I, 2005. http://tel.archives-ouvertes.fr/tel-00275264.
Texto completo da fonteKarouni, Ali. "Réalisation d'une plate-forme fondée sur la théorie de la décision, l'optimisation et la diffusion pour prévoir, modéliser et gérer une catastrophe naturelle : les feux de forêts". Thesis, Angers, 2014. http://www.theses.fr/2014ANGE0043.
Texto completo da fonteDuring the last decades, the number of occurrences of natural disasters has increased noticeably which lead to catastrophic results on human as well as properties and green areas. But despite the huge amount of damages, this helps to draw the attention of researchers, organizations and the various governmental and non-governmental sectors towards analyzing these phenomena, their causes & effects, allowing to recognize their behaviors and the methods to predict their occurrence and thus reaching the phase of risk management contributing to prevent their incidence or limit the consequences. As the risk of happening often exists, the instantaneous presence of dangers is also possible. Here appears the importance of any effort that serves to tackle such crises. In this contribution, the phenomenon of forest fires is studied. In Lebanon, green areas declined dramatically during the last decades, what imposes an urgent intervention with strict governmental policies and support of non-governmental organizations. The global orientation is towards techniques that predict high fire risks, allowing for precautions to preclude fire occurrences or at least limit their consequences. Forest fire prediction proves to contribute in preventing fire occurrence or reducing its catastrophic impacts in worst cases on human lives, properties and green forestry
Eyssette, Roland. "Caractérisation et modélisation des effets de surpression en champ proche et du chargement au sol du BLEVE". Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEM020/document.
Texto completo da fonteBoiling Liquid Exploding Vapor Explosion (BLEVE) is one of the most feared accident in the industry. Even though it has been studied for over 6 decades, many safety questions remain poorly answered: what happens if a BLEVE occurs in a congested urban or industrial area? What if a road tanker BLEVE happens on a bridge? These questions require to look closer to the vessel. This work focuses on understanding the physics involved in overpressure generation in the near field surrounding of the vessel, to understand the contribution of the fluid phases (liquid and vapor) in the near-field hazards of a BLEVE. For this purpose, a small scale experimental prototype was designed to reproduce realistic BLEVE failure. Twenty-four propane BLEVEs were performed. A wide range of data was recorded from these tests: blast overpressure all around the vessel, transient pressure inside the vessel, ground loading under the vessel, and high speed imaging through various angles. Results give more insight on the anisotropy of the pressure field around the cylindrical vessel. It also shows a strong dependency between vapor content and maximum overpressure from the lead shock. Moreover, the chronology of the phase change observed through transient pressure measurements show that the main contributor of the maximum overpressure is the vapor phase. The phase change is studied through pressure transient in the vessel and high speed imaging, giving a better understanding of the time scales involved with this phenomenon. Finally, ground loading measurements are analyzed to give insight on the order of magnitude involved in this hazard
Lacroix, Marie. "Méthodes pour la reconstruction, l'analyse et l'exploitation de réseaux tridimensionnels en milieu urbain". Electronic Thesis or Diss., Paris 6, 2017. http://www.theses.fr/2017PA066001.
Texto completo da fonteDisasters like the ones that happened in Ghislenghien (Belgium), Ludwigshafen (Germany), or Lyon (France), have been attributed to excavations in the vicinity of gas pipelines. Though pipes are one of the safest methods of transportation for conveying hazardous substances, each year many cases of damage to gas pipes are recorded in France. Most of them are due to works in the vicinity of the networks and some illustrate the lack of reliability of the provided information. Concessionaries have to take stock of the situation and to suggest areas of improvement, so that everyone could benefit from networks becoming safer.To prevent such accidents which involve workers and the public, French authorities enforce two regulations: DT / DICT: reform of the network no-damage by securing the excavations, Multifluide: reform which is interested in securing networks of hazardous events.So, to avoid such accidents or other problems, it is necessary to acquire and control the 3D information concerning the different city networks, especially buried ones.Preventive strategies have to be adopted. That’s why working on the networks and their visualization and risk cartography, taking the blur into account, is a recent and appropriate research. The software applications I develop should help the utility and construction contractors and focus on the prevention of hazardous events thanks to accurate data sets for users and consumers, the definition of a geomatics network but also some methods such as triangulation methods, element modeling, geometrical calculations, Artificial Intelligence, Virtual Reality
Lacroix, Marie. "Méthodes pour la reconstruction, l'analyse et l'exploitation de réseaux tridimensionnels en milieu urbain". Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066001/document.
Texto completo da fonteDisasters like the ones that happened in Ghislenghien (Belgium), Ludwigshafen (Germany), or Lyon (France), have been attributed to excavations in the vicinity of gas pipelines. Though pipes are one of the safest methods of transportation for conveying hazardous substances, each year many cases of damage to gas pipes are recorded in France. Most of them are due to works in the vicinity of the networks and some illustrate the lack of reliability of the provided information. Concessionaries have to take stock of the situation and to suggest areas of improvement, so that everyone could benefit from networks becoming safer.To prevent such accidents which involve workers and the public, French authorities enforce two regulations: DT / DICT: reform of the network no-damage by securing the excavations, Multifluide: reform which is interested in securing networks of hazardous events.So, to avoid such accidents or other problems, it is necessary to acquire and control the 3D information concerning the different city networks, especially buried ones.Preventive strategies have to be adopted. That’s why working on the networks and their visualization and risk cartography, taking the blur into account, is a recent and appropriate research. The software applications I develop should help the utility and construction contractors and focus on the prevention of hazardous events thanks to accurate data sets for users and consumers, the definition of a geomatics network but also some methods such as triangulation methods, element modeling, geometrical calculations, Artificial Intelligence, Virtual Reality
Ferrer, Laëtitia. "Evaluation de l'efficacité de l'information préventive sur les risques majeurs destinée au grand public : application au DICRIM". Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0207/document.
Texto completo da fonteRaising the general public's sensitisation of major hazards is a current issue in their prevention and is based in particular on the communication of preventive information. In France, this communication is a regulatory obligation. One can then question its effectiveness and how its content and form are perceived by the population. In this thesis, approaches contributing to the evaluation of the effectiveness of preventive risk communication documents are proposed with an application to the DICRIM (“Document d’Information Communal sur les Risques Majeurs” in French; “Communal Information Document on Major Risks” in English). They cross methods at the interface between engineering sciences (method of operational safety), cognitive sciences (knowledge modelling) and human and social sciences (interviews and discourse analysis). The developments concern: - a model for assessing the content conformity of a given DICRIM with the law; - elements of cognitive representations of elected representatives and inhabitants relative to the DICRIM and major hazards in general; - a production of performance indicators and a model for evaluating the performanceof a DICRIM.Model validations were carried out on real cases. The models also provide feedback to improve the effectiveness of the document if necessary, based on the scores obtained using the indicators. Decision support models can be used by municipalities or specialized design offices on any existing or newly created DICRIM. Their use does not require the implementation of particular means. In addition, the models have generic components applicable to other types of risk communication tools
Soukhova, Natalia. "Etude de la distribution du 137Cs et modélisation des tranferts sol-plante dans les écosystèmes forestiers de la région de Briansk fortement contaminés par l'accident de Tchernobyl". Besançon, 2000. http://www.theses.fr/2000BESA2070.
Texto completo da fonteThis work presents the results of the study of 137Cs distribution and transfer in forest ecosystems of Briansk (Russia). This region was heavily contaminated in the result of radioactive fallout from Chernobyl NPP accident in 1986. Thus the level of contamination allows to get reliable results. Different sites with pedological and forest features were chosen with the aim to study the influence of these parameters on 137Cs migration in soil and its transfer into vegetation. 137Cs migration in soil depends on forest litter thickness and composition. At present time the principal part of 137Cs is situated in the limit between litter and mineral horizons. Sequential extractions obtained from soil samples revealed the existence of geochemical barrier. This barrier is located just beneath the forest litter. 137Cs distribution in different parrts (wood, bark, leaves, sap, roots) of coniferous and deciduous woody species (Pinus sylvestris and Betula pendula) was studied. 137Cs is very mobile in trees and our results show that its distribution can be easily explained by structure and functioning of studied species. Thus the difference in radial 137Cs distribution in trunk of studied species is closely linked to the difference in radial rays composition. Moreover it was demonstrated in some examples that 137Cs transfer in different types of forest vegetation depends on factors as : vertical distribution of 137Cs bioavailable forms in soil profile, vertical distribution of plant roots and some specific capacities of plants to accumulate 137Cs. The set of data gathered during the present work allowed us to develop one mathematical model of 137Cs migration and fixation in forest soil. Moreover conceptual models of 137Cs transfer in forest ecosystems were designed and a new approach to estimate the contamination of forest compartments contamination by 137Cs was proposed
Gouhier, Mathieu. "Application du radar Doppler (VOLDORAD) à l'étude de la dynamique des éruptions Stromboliennes de l'Etna". Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2008. http://tel.archives-ouvertes.fr/tel-00731252.
Texto completo da fonteAndré, Camille. "Analyse des dommages liés aux submersions marines et évaluation des coûts induits aux habitations à partir de données d'assurance : perspectives apportées par les tempêtes Johanna (2008) et Xynthia (2010)". Phd thesis, Université de Bretagne occidentale - Brest, 2013. http://tel.archives-ouvertes.fr/tel-00961315.
Texto completo da fonteBelharet, Mokrane. "Modélisation numérique du transfert du radiocésium dans les chaines trophiques pélagiques marines suite à l'accident nucléaire de Fukushima Dai-ichi (côte Pacifique du Japon)". Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30339/document.
Texto completo da fonteHuge amounts of radionuclides, espicially 137Cs, were released to the coastal northwestern Pacific ocean after the Fukushima nuclear power plant accident, that occurred on 11 March 2011. The resultant radiocesium contamination was quickly transferred to marine biota resulting in elevated cesium levels in various organisms. Using a modelling approach, this work aims to study the 137Cs transfer to the marine pelagic food chains, from plankton populations to the large piscivorous fishes. Coupling the radioecological model, developed in this study, with an ecosystem model comprising an NPZD biogeochemical model and a regional ocean circulation model, is appeared to be the most adapted tool for modelling of plankton populations contamination in this accidental situation. The results of this study showed high contamination levels in the plankton populations, especially in the vincity of the power plant, where the maximal concentrations are estimated to be about 4 orders of magnitude higher than those observed before the accident. In spite of these high contamination levels, the maximum 137Cs absorbed dose rates for phyto- and zooplankton populations were estimated to be well below the 10 Gy/h benchmark value, from which a measurable effect on the marine biota can be observed. This study has also highlighted the predominance of the cesium uptake from food and the presence of biomagnification potential at this trophic level. The radioecological model developed to study the nektonic species contamination is based on the individual size. In this approach, each species is represented by a set of cohorts. The number of these cohorts is a function of the species life span and reproduction frequency. Unlike traditional approaches, the organism ingestion rate and diet composition considered in this modelling approach are not constant, but vary over the time according to the size of the organism. The model results are in general satisfactory, and the validation is carried out in both equilibrium and accidental situations. This study highlighted the importance of the organism migratory movements in the radioecological modelling espicially in the accident situations caracterized by a very high spatial variability of radionuclides concentrations in the seawater. The detailed caracteristics of 137Cs concentration dynamics in the different species are discussed. The contamination levels estimated for the different species are significantly higher than those observed before the accident, with a clear tendency to increase with individual size
Karouni, Ali. "Réalisation d'une plate-forme fondée sur la théorie de la décision, l'optimisationet la diffusion pour prévoir, modéliser et gérer une catastrophe naturelle : les feux de forêts". Thesis, 2014. http://www.theses.fr/2014ANGE0043.
Texto completo da fonteDuring the last decades, the number of occurrences of natural disasters has increased noticeably which lead to catastrophic results on human as well as properties and green areas. But despite the huge amount of damages, this helps to draw the attention of researchers, organizations and the various governmental and non-governmental sectors towards analyzing these phenomena, their causes & effects, allowing to recognize their behaviors and the methods to predict their occurrence and thus reaching the phase of risk management contributing to prevent their incidence or limit the consequences. As the risk of happening often exists, the instantaneous presence of dangers is also possible. Here appears the importance of any effort that serves to tackle such crises. In this contribution, the phenomenon of forest fires is studied. In Lebanon, green areas declined dramatically during the last decades, what imposes an urgent intervention with strict governmental policies and support of non-governmental organizations. The global orientation is towards techniques that predict high fire risks, allowing for precautions to preclude fire occurrences or at least limit their consequences. Forest fire prediction proves to contribute in preventing fire occurrence or reducing its catastrophic impacts in worst cases on human lives, properties and green forestry