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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Metodologia diagnóstica para as Unidades de Conservação Estaduais do Espírito Santo : condições para sua gestão e para prevenção e combate aos incêndios florestais / Diagnostic methodology for the State Conservation Units of the Espírito Santo : Conditions for its management and prevention and combat of forest fires

Tebaldi, André Luiz Campos 17 December 2010 (has links)
Made available in DSpace on 2016-12-23T13:51:51Z (GMT). No. of bitstreams: 1 Dissertacao de Andre Luiz Campos Tebaldi (2).pdf: 3827928 bytes, checksum: 67ec69edb91a541a3f14c7f9ca6a5731 (MD5) Previous issue date: 2010-12-17 / The research had the aim to develop diagnostic methods for the state Conservation Units of the Holy Spirit: Conditions for its management, prevention and fighting forest fires. For this analysis, we attempted to work with six specific objectives which are: to characterize the conditions and infrastructure management, to diagnose the quantitative availability of personnel and equipment to prevent and fight forest fires, identify the major causes of the occurrences of forest fires related to them with the major threats to ecosystems, identifying the size class distribution of the burned areas, identify the main types of fires, the main diagnostic prevention activities developed. The analysis included the participation of all managers of the sixteen state conservation units created by the year 2009. The results indicated that the Reserva Biológica Duas Bocas with the best conditions for management and infrastructure (82%) and the Reserva de Desenvolvimento Sustável Concha D ostra has the worst conditions (5%). Parque Estadual de Itaúnas showed greater staff shortages. Availability of operational equipment, we found that 75% of the units are fully protected at a deficit. In respect of tools identified that the Parque Estadual Cachoeira da Fumaça had the largest deficit and no protective equipment in the units. The inadequate infrastructure (14%) and hunting (12%) are the main threats to the state units. Over 50% of fires in the state units are predominantly surface area burned ranged from 0.1 to 40 hectares. Approximately 40% of causes are burns cleaner and 20% for arson. The main preventive activities carried out are inter-institutional integration and monitoring unit (22%). The results will serve as an efficient tool for planning and management for the State Government to implement actions and prevention activities in protected areas / A pesquisa teve o objetivo principal desenvolver metodologia diagnóstica para as Unidades de Conservação estaduais do Espírito Santo: Condições para sua gestão, prevenção e combate aos incêndios florestais. Buscou-se trabalhar com seis objetivos específicos sendo eles: caracterizar as condições de gestão e infraestrutura; diagnosticar a disponibilidade quantitativa de pessoal e equipamentos para prevenção e combate aos incêndios florestais; identificar os principais grupos de causa das ocorrências de incêndios florestais relacionando-as com as principais ameaças aos ecossistemas; identificar a distribuição das classes de tamanho das áreas queimadas, identificar os principais tipos de incêndios; diagnosticar as principais atividades de prevenção desenvolvidas. A análise contou com a participação de todos os gestores das dezesseis Unidades de Conservação estaduais criadas até o ano de 2009. Os resultados indicaram que a Reserva Biológica de Duas Bocas possui melhores condições para gestão e infraestrutura (82%) e a Reserva de Desenvolvimento Sustentável Concha D ostra possui piores condições (5%). O Parque Estadual de Itaúnas apresentou maior déficit de pessoal. Na disponibilidade de equipamentos operacioais, observou-se que 75% das Unidades de proteção integral estão com déficit. Na relação de ferramentas identificou-se que o Parque Estadual da Cachoeira da Fumaça apresentou o maior déficit e não há equipamentos de proteção individual nas Unidades. A infraestrutura inadequada (14%) e a caça (12%) são as principais ameaças às Unidades estaduais. Mais de 50% dos incêndios nas Unidades estaduais são de superfície com predominância de área queimada variando de 0,1 à 40 hectares. Aproximadamente 40% das causas são queimas para limpeza e 20% incendiários. As principais atividades preventivas realizadas são integração interinstitucional e vigilância da unidade (22%). Os resultados servirão como uma eficiente ferramenta de planejamento e gestão para o Governo do Estado implementar ações e atividades preventivas nas Unidades de Conservação
192

Etude préliminaire sur les possibilités d'utilisation des images du capteur AVHRR des satellites atmosphériques de la NOAA pour la détection des zones brûlées dans les Ghâts occidentaux

De Caluwe, Nicolas January 2006 (has links)
Doctorat en Sciences / info:eu-repo/semantics/nonPublished
193

Modélisation hybride stochastique-déterministe des incendies de forêts

Billaud, Yann 06 May 2011 (has links)
Les grands incendies de forêts sont responsables de la quasi-totalité de la surface brulée et contribuent, par les émissions de particules et de gaz à effet de serre qu’ils génèrent, au réchauffement climatique. Des observations satellitaires ont mis en évidence un comportement fractal que l’on attribue aux hétérogénéités locales (topographie, végétation, conditions météorologiques) rencontrées par ces feux lors de leur propagation. Le présent travail a été consacré au développement et à la validation d’un modèle hybride de propagation d’incendie, capable de reproduire ce comportement. Ce modèle est une extension du modèle original de réseau de « petit monde » où les phénomènes qui se produisent à l’échelle macroscopique, comme le rayonnement du front de flammes et l’inflammation pilotée de la strate végétale sont traités de façon déterministe. Pour décrire le rayonnement, nous avons utilisé un modèle de flamme solide couplé à une méthode de Monte Carlo. La validation a porté sur des configurations simples, mais aussi plus complexes, comme le rayonnement d’un front hétérogène de flammes ou celui d’une flamme d’éthanol. Un modèle d’inflammation a ensuite été élaboré et appliqué à des litières d’aiguilles de pin. Les paramètres du modèle ont été optimisés par un algorithme génétique, conduisant au meilleur accord avec les résultats expérimentaux, en termes de temps d‘inflammation et de perte de masses. Il a été montré que l’oxydation du résidu charbonneux joue un rôle prépondérant sur l’inflammation à bas flux. Le modèle de propagation de petit monde a été validé sur un brûlage dirigé et sur un feu historique, montrant un bon accord en termes de surface brûlée, de vitesse de propagation, de contours de feu, et de propriétés fractales. On a montré qu’il pouvait être utilisé pour le dimensionnement d’ouvrages de défense, comme les coupures de combustible, ou pour expliquer le comportement atypique du feu dans certaines situations (talweg, ruptures de pente, etc.). Son application a également permis d’optimiser le nombre et l’emplacement d’un réseau de capteurs déployés dans la végétation dans le but de localiser précisément et détecter précocement le départ d’un feu. / Most of the area burned by forest fires is attributable to the few fires that escape initial attack to become large. As a consequence large-scale fires produce a large amount of green-house gases and particles which contribute to the global warming. Heterogeneous conditions of weather, fuel, and topography are generally encountered during the propagation of large fires. This shapes irregular contours and fractal post-fire patterns, as revealed by satellite maps. Among existing wildfire spread models, stochastic models seem to be good candidates for studying the erratic behavior of large fires, due to the above-mentioned heterogeneous conditions. The model we developed is a variant of the so-called small-world network model. Flame radiation and fuel piloted ignition are taken into account in a deterministic way at the macroscopic scale. The radiative interaction domain of a burning cell is determined from Monte Carlo simulation using the solid flame model. Some cases are studied, ranging from relatively simple to more complex geometries like an irregular flame fronts or an ethanol pool fire. Then, a numerical model is developed to investigate the piloted ignition of litters composed of maritime pine needles. A genetic algorithm is used to locate a set of model parameters that provide optimal agreement between the model predictions and the experimental data in terms of ignition time and mass loss. The model results had shown the importance of char surface oxidation for heat fluxes close to the critical flux for ignition. Finally, the small-world network model was used to simulate fire patterns in heterogeneous landscapes. Model validation was achieved to an acceptable degree in terms of contours, burned area and fractal properties, through comparison of results with data from a small controlled bushfire experiment and a historical Mediterranean fire. Therefore, it has been proven to be a powerful tool in the sizing of fortifications as fuel break areas at the wildland urban interface or in the understanding of atypical behavior in particular configurations (talweg, slope breaking, etc.). It has also been used for the optimization of an in-situ sensor network whose purpose is to detect precociously and to locate precisely small fires, preventing them from spreading and burning out of control. Our objective was to determine the minimum number and placement of sensors deployed in the forest.
194

The Children's Forest Association fire ecology hike

Dufilho, Michael Stephen 01 January 2005 (has links)
This project provides a fire ecology lesson to accompany a hike for student groups from fourth through eighth grade. The lesson plan will acquaint students with the beneficial aspects of forest fires.
195

Evaluation de la fiabilité des réseaux de capteurs sans fils pour la détection en milieu naturel / Assessment of the Reliability of Wireless Sensor Networks for Detection in Natural Environments

Kassan, Rabih 24 May 2017 (has links)
L’objectif de la thèse est d’évaluer la fiabilité des réseaux de capteurs (WSN) en milieu naturel. L’évaluation prend en compte les composants physiques des nœuds de capteurs, les cellules photovoltaïques éventuelles (PV), les batteries rechargeables ou non, les protocoles de communications et d’échange de données ainsi que les éléments nécessaires pour une détection efficace, en particulier les feux de forêt. L’étude traite d’abord du fonctionnement du réseau de capteur dans la nature en prenant en compte sa consommation d’énergie et les défaillances physiques et fonctionnelles pour évaluer sa fiabilité. Puis, la fiabilité est comparée entre un réseau sans PV (WSN) et avec PV (PV-WSN) dans des conditions d’échange de données difficiles. Enfin, l’évaluation de la fiabilité des PV-WSN est effectuée dans le cadre de la détection et de la propagation des feux de forêts avec les mêmes conditions d’échange de données. Les principales hypothèses considérées sont : des distributions de capteurs aléatoires dans des réseaux avec un seul nœud « sink », des nœuds identiques, l’affaiblissement du signal radio dû aux obstacles naturels, une propagation de feu uniforme et elliptique, une végétation homogène, une perte possible de paquets de données ainsi que l’utilisation du protocole de routage « Dynamic Source Routing (DSR) ». Un simulateur a été développé pour effectuer les différentes études. Les résultats obtenus montrent l’importance des défaillances physiques pour l’évaluation de la fiabilité et pour la prolongation de la durée de vie des WSN et PV-WSN / The objective of my thesis was to evaluate the reliability of wireless sensor networks (WSN) in natural settings. My evaluation takes into account the physical components of sensor nodes, photovoltaic (PV) cells, rechargeable and non-rechargeable batteries, communication and data transmission protocols, and elements necessary for effective detection, especially for the case of forest fires. The study first deals with the functioning of a WSN in nature by taking into account its energy consumption, and physical and functional failures to assess its reliability. Reliability is then compared between a PV-free (WSN) and PV- (PV-WSN) network under complex data exchange conditions. Finally, the evaluation of the reliability of the PV-WSN is carried out in the context of the detection and propagation of forest fires under the same conditions of data exchange. The main assumptions considered are: the WSN is structured randomly with one sink per cluster and identical sensors, environmental and orientation losses affect PV-cell recharge, the radio signal may be weakened by natural obstacles, fire propagation is uniform and elliptical, vegetation is homogeneous, and there is communication loss using the Dynamic Source Routing (DSR) protocol. A simulator was developed to carry out these assessments. The results obtained show the importance of physical failures in assessing reliability and extending WSN and PV-WSN lifetime
196

Vivre avec le feu en région méditerranéenne : une approche participative multicritère et multi-scénarios appliquée au cas du massif des Maures (Var, France) / Living with fire in the Mediterranean region. A participatory multi-criteria and multi-scenario approach applied to the Massif des Maures (Var, France).

Merino, Albert 26 November 2015 (has links)
Dans cette thèse, nous présentons une évaluation multicritère de plusieurs « scénarios de vie avec le feu » en forêt méditerranéenne. Le cas d’études concerne le massif des Maures (Var ; France), un territoire fortement soumis au risque « feux de forêt » et ayant connu d’importantes transformations socio-économiques au cours des dernières décennies. Cette étude cherche également à tester et comparer la pertinence de plusieurs cadres évaluatifs comme outils d’aide à la gouvernance du risque « feux de forêt ». La thèse est composée de trois parties principales clairement distinctes d’un point de vue aussi bien thématique que méthodologique. La première partie de la thèse a pour objet l’« Economie du feu », autrement dit, l’ensemble de concepts et d’outils généralement proposés par la Science Economique pour l’analyse du risque « feux de forêt » (modèle C+NVC, « budget optimal de protection », etc.). Nous soulignons par rapport à ce premier cadre évaluatif jusqu’à trois sophismes fondamentaux qui démontrent son inadéquation par rapport à la complexité, l’incertitude, l’ambiguïté et l’incommensurabilité qui caractérisent le phénomène du feu. La thèse se focalise dans un deuxième temps sur la présentation d’une approche alternative au sein de laquelle plusieurs scénarios semi-qualitatifs sont évaluées dans une logique participative et multicritère. La deuxième partie de la thèse est ainsi consacrée à la présentation de l’approche des Scénarios Environnementaux, puis de chacune des étapes du processus prospectif mené sur le terrain avec la participation des acteurs locaux. Ce processus aboutit à quatre « avenirs du feu » dans les Maures : (i) l’AFFRONTEMENT technique ; (ii) la (RE)COLONISATION de la forêt ; (iii) la DOMESTICATION du feu ; et (iv) l’ADAPTATION collective. Enfin, dans la troisième partie de la thèse, nous présentons les Approches Participatives MultiCritère (APMC), puis nous analysons le processus d’exploration réalisé sur le terrain par les acteurs locaux eux-mêmes à travers une plateforme heuristique inspirée de deux APMC communément employées dans la gestion de systèmes socio-écologiques et la gouvernance des risques, à savoir, la Multi-Criteria Mapping (cartographie multicritère) et l’Approche INTÉGRAAL. L’analyse des résultats obtenus à travers ce processus d’exploration permettent d’établir plusieurs recommandations susceptibles d’améliorer les pratiques actuelles de gouvernance du risque et de décupler l’acceptabilité sociétale des mesures de gestion aujourd’hui en place. / This thesis aims to: (i) explore and evaluate several ways of living with fire in Mediterranean forests; (ii) appraise different evaluative frameworks for wildfire risk governance. The case study concerns the Massif des Maures (Var; France), a fire-prone territory where structural socio-economic transformations are coming about since 50 years now. The thesis consists of three main parts clearly distinguishable (thematically as well as methodologically). First part focuses on “Fire Economics”, that is, the set of theoretical concepts and methodological tools commonly applied by economists for the study of wildfire risk (C+NVC model, “most efficient program level”, etc.). We highlight up to three fundamental sophisms in such an evaluative framework. We thus underline its inadequacy for dealing with the complexity, uncertainty, ambiguity and incommensurability of wildfires phenomenon. The focus of the thesis moves then to the presentation of an alternative approach in which several semi-qualitative and integrated Scenarios are explored through an inclusive Multi-Criteria reasoning. Second part thus treats Environmental Scenarios, an approach which is first presented in a general way and whose application to our case study is then analysed in detail, from the very first interviews with local actors to the final scenarios generated with their participation. These scenarios are: (i) Technical Confrontation; (ii) Forest (re)Colonisation; (iii) Fire Domestication; and (iv) Collective Adaptation. Third part deals with Participatory Multi-Criteria Approaches (PMCA). We first present and contextualise these evaluative frameworks as an example of Value-Articulating Institution (VAI). We then apply to our case study a hybrid PMCA inspired from two approaches frequently used in social-ecological systems management and risk governance: Multi-Criteria Mapping and INTÉGRAAL Approach. The thesis concludes with several recommendations that could improve social acceptability of current fire management strategies and more generally, enhance fire risk governance practices.
197

[en] DISTRIBUTION GRID PLANNING WITH LINES INVESTMENT AND TOPOLOGY RECONFIGURATION FOR WILDFIRE RESILIENCE UNDER DECISION-DEPENDENT UNCERTAINTY / [pt] PLANEJAMENTO DE SISTEMAS DE DISTRIBUIÇÃO COM INVESTIMENTO EM LINHAS E RECONFIGURAÇÃO DE TOPOLOGIA PARA RESILIÊNCIA A INCÊNDIOS FLORESTAIS SOB INCERTEZA-DEPENDENTE DE DECISÃO

FELIPE NEVES PIANCÓ 05 March 2024 (has links)
[pt] Os incêndios florestais podem ser uma fonte de vulnerabilidade para sistemas de potência. Esses eventos podem afetar especialmente a operação de sistemas de distribuição, interrompendo o fornecimento de energia, aumentando os custos, e diminuindo a confiabilidade. Nesta dissertação, é considerada a relação entre as decisões operativas e a probabilidade de falha nas linhas sob o contexto de queimadas. Este tipo de estudo ainda não foi devidamente avaliado pelo meio acadêmico. Ao não reconhecer este aspecto, o funcionamento dos sistemas de potência pode estar sendo prejudicado. A modelagem adequada dessa dependência poderia reduzir a incidência de queimadas e perda de carga. Considerando este aspecto, um problema de otimização distributivamente robusto de dois estágios com incerteza endógena foi desenvolvido para considerar a operação multiperíodo de sistemas de distribuição. O primeiro estágio determina a topologia da rede e os investimentos nas linhas, e o segundo estágio avalia o custo operacional esperado no pior caso. Nessa estrutura, a incerteza é modelada de forma dependente das decisões do modelo, onde as probabilidades de falha da linha são em função do fluxo de potência das próprias linhas. Um método iterativo é proposto para resolver este modelo e uma análise fora da amostra é desenvolvida para validação através de diferentes estudos. Os resultados mostraram que, ao negligenciar a dependência da incerteza, uma maior perda de carga e um maior custo operacional são esperados. Ao considerar esta nova abordagem, a confiabilidade da rede pode ser melhorada e as consequências dos incêndios podem ser mitigadas com ações mais econômicas. / [en] Wildfires can be a source of vulnerability for power systems operations. These events can especially affect the operation of distribution systems. They can interrupt energy supply, increase costs, and decrease grid resilience. Numerous approaches can be executed to prevent them. In this dissertation, it is considered the relationship between operative actions and the probability of wildfire disruption. This type of study has not been properly evaluated in technical and scientific literature. By not recognizing this aspect, the operation of power systems may be impaired. Properly modeling this dependency could lower wildfire disruption and loss of load. Considering this, a two-stage distributionally robust optimization problem with decision-dependent uncertainty is developed to consider distribution system multiperiod operation. The first stage determines the optimal switching actions and line investments, and the second stage evaluates the worst-case expected operation cost. It is designed a decision-dependent uncertainty framework where the line failure probabilities are a function (dependent) of its power flow levels. An iterative method is proposed to solve this model and an out-of-sample analysis is developed to validate it through different case studies. Results showed that, by neglecting the uncertainty dependency on operative decisions, there could be a higher expected loss of load and a higher operational cost. By considering this new approach when operating power lines, the grid s resilience could be improved and wildfire consequences can be mitigated with less costly actions.
198

La terminologia catalana dels incendis forestals. Recerca, anàlisi i proposta de diccionari especialitzat català-castellà-anglès

Gil Puig, Adriana 06 September 2022 (has links)
[ES] Los incendios forestales son un tema de flamante actualidad en la cuenca mediterránea, han pasado de ser un elemento tradicional de gestión agroforestal a devenir la principal amenaza para la supervivencia de los bosques como consecuencia del cambio climático y del abandono de las zonas rurales. Esta tesis aborda el estudio de la terminología catalana de este campo con tres objetivos: compilarla, caracterizarla y ofrecer una aplicación terminológica adaptada a las necesidades profesionales. Desde el punto de vista teórico, se enmarca en la Teoría Comunicativa de la Terminología (Cabré, 1999) y se fundamenta en las investigaciones sobre los lenguajes de especialidad, la terminología y el trabajo terminológico, que tienen como objeto de estudio principal los términos y como producto prototípico los diccionarios. Desde el punto de vista empírico, acomete una investigación terminográfica sistemática monolingüe con equivalencias siguiendo una metodología ampliamente contrastada en terminología catalana. Primero, se analizan las necesidades terminológicas del personal especialista en incendios forestales y su contexto profesional. Segundo, se elabora un corpus de textos de la especialidad, a partir del cual se realiza la extracción semiautomatizada de los términos mediante la estación de trabajo terminológico Terminus, atendiendo a un árbol de campo previamente preestablecido. A continuación, se configura un fichero terminológico de más de un millar de términos seleccionados del campo de estudio y se completa con definiciones, subcampos, contextos, equivalencias y otras informaciones. Tercero, se analiza el listado de términos obtenido desde un punto de vista formal, semántico, neológico y contrastivo, para establecer los rasgos singulares. Finalmente, se desarrolla una propuesta de diccionario terminológico de incendios forestales catalán-castellano-inglés dirigida al personal experto. / [CA] Els incendis forestals són un tema de flamant actualitat a la conca mediterrània, han passat de ser un element tradicional de gestió agroforestal a esdevenir la principal amenaça per a la supervivència dels boscos com a conseqüència del canvi climàtic i de l'abandonament de les zones rurals. Aquesta tesi aborda l'estudi de la terminologia catalana d'aquest camp amb tres objectius: compilar-la, caracteritzar-la i oferir una aplicació terminològica adaptada a les necessitats professionals. Des del punt de vista teòric, s'emmarca en la Teoria Comunicativa de la Terminologia (Cabré, 1999) i té les bases en les recerques sobre els llenguatges d'especialitat, la terminologia i el treball terminològic, que tenen com a objecte d'estudi principal els termes i com a producte prototípic els diccionaris. Des del punt de vista empíric, acompleix una recerca terminogràfica sistemàtica monolingüe amb equivalències seguint una metodologia àmpliament contrastada en terminologia catalana. Primer, s'analitzen les necessitats terminològiques del personal especialista en incendis forestals i el seu context professional. Segon, s'elabora un corpus de textos de l'especialitat, a partir del qual s'escomet l'extracció semiautomatitzada dels termes mitjançant l'estació de treball terminològic Terminus, tot atenent a un arbre de camp prèviament preestablert. A continuació, es configura un fitxer terminològic de més d'un miler de termes seleccionats de l'especialitat i es completa amb definicions, subcamps, contextos, equivalències i altres informacions. Tercer, s'analitza el llistat de termes obtingut des d'un punt de vista formal, semàntic, neològic i contrastiu, per tal d'establir-ne els trets singulars. Finalment, es desenvolupa una proposta de diccionari terminològic d'incendis forestals català-castellà-anglès adreçada a personal expert. / [EN] Forest fires are currently a topical issue in the Mediterranean basin. They have ceased to be a traditional element of agroforest management to become the main threat for the survival of the forests because of climatic change and abandonment of rural areas. This thesis addresses the study of the Catalan terminology of this field with three main aims: compile it, characterize it and offer a terminological application adapted to the needs of the specialists. From the theoretical point of view, it fits in the framework of the Communicative Theory of Terminology (Cabré, 1999) and is based on the studies on specialized languages, terminology and the terminological work, that have the terms themselves as the main object of study, and the dictionaries as a main product. From an empirical point of view, it accomplished a terminographic monolingual systematic research with equivalences following a widely contrasted methodology in Catalan terminology. First, the terminological needs of the specialists in forest fires and their professional context are analyzed. Second, a corpus of specialized texts is created, from which a semiautomated extraction of the terms by means of the terminological workstation Terminus is done, attending to a preestablished field tree. Following this, a terminological file is compiled, with more than a thousand terms selected by field and completed with definitions, subfields, contexts, equivalences and other information. Third, the list of terms obtained is analyzed from a formal, semantic, neologistic and contrasted point of view, in order to establish their distinctive traits. Finally, a proposal for a terminological forest fires dictionary in Catalan-Spanish-English addressed to experts is presented. / Gil Puig, A. (2022). La terminologia catalana dels incendis forestals. Recerca, anàlisi i proposta de diccionari especialitzat català-castellà-anglès [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/186183
199

Análisis de las señales electrofisiológicas en Pinus halepensis Mill como base a su aplicación en sensores inalámbricos para la prevención de incendios forestales

Zapata Zapata, Rodolfo 10 October 2023 (has links)
Tesis por compendio / [ES] Los bosques de Pinus halepensis, están sometidos a periodos con condiciones meteorológicas extremas de altas temperaturas y estrés hídrico. Estas condiciones, junto al actual contexto de emergencia climática genera condiciones ideales para los grandes incendios forestales de proporciones catastróficas con graves consecuencias en la salud y el bienestar de las personas. En este contexto, una de las disciplinas de conocimiento científico que apenas se han investigado hasta la fecha en relación con el riesgo de incendios forestales es la electrofisiología vegetal. Por ello, en la presente tesis se expone la evaluación experimental de las señales eléctricas vegetales como posibles variables equivalentes del estado fenológico en los modelos de gestión, como base para el futuro desarrollo de sistemas de redes de sensores inalámbricos, todo ello a través del análisis de las características estáticas y dinámicas de las señales electrofisiológicas de la principal especie arbórea de la cuenca mediterránea occidental, el Pinus halepensis. La tesis se ha estructurado en tres capítulos, siguiendo cada uno de ellos el método científico. En el primer capítulo se analiza la evaluación de algunos de los factores estáticos más significativos que influyen en el patrón de distribución de las señales electrofisiológicas del Pinus halepensis. Tras un diseño muestral adecuado, los resultados demuestran que la madurez del árbol influye directamente en la tensión eléctrica determinada por la tensión medida, siendo los árboles jóvenes los que presentan una mayor amplitud en la señal eléctrica, la cual se muestra uniforme en el árbol, siendo independiente de la colocación de los electrodos en altura y en orientación cardinal. En el segundo capítulo se analiza la evolución temporal de la señal eléctrica registrada, tanto diaria como anual. Los resultados obtenidos demuestran que las señales electrofisiológicas presentan valores significativamente más altos y de mayor amplitud durante los periodos más húmedos con temperaturas moderadas, mientras que las señales son representativamente mucho más bajas, durante los períodos con mayor estrés vegetativo del año. La metodología aplicada y los resultados obtenidos en este capítulo de la tesis demuestran que las señales electrofisiológicas pueden ser consideradas un indicador del estado fisiológico de los árboles en situaciones de estrés vegetativo. Finalmente, en el tercer capítulo de la tesis se analiza la evaluación de las señales electrofisiológicas como variables a incluir en los modelos de gestión del riesgo de incendio forestal. Los resultados obtenidos nos han permitido demostrar que el LFMC del Pinus halepensis no muestra variaciones estacionales significativas bajo la influencia de factores extremos de riesgo de incendio, mientras que las diferencias registradas en las señales electrofisiológicas muestran oscilaciones con variaciones significativas, que están fuertemente correlacionadas con los periodos de condiciones meteorológicas extremadamente favorables para los incendios forestales. Finalmente, también se ha podido demostrar una muy alta correlación entre las tensiones medidas y el principal índice de riesgo de incendio utilizados por las agencias de emergencias Con todos los resultados obtenidos, podemos concluir finalmente que las variaciones en las señales electrofisiológicas están estrechamente relacionadas con el estado fenológico de los Pinus halepensis y con el riesgo de incendio forestal. Lo que abre la posibilidad de una monitorización in situ de las masas forestales en las que domina esta especie, lo que sería fácilmente integrable en los sistemas de modelización y gestión preventiva de los incendios forestales en los ecosistemas mediterráneos. / [CA] Els boscos de Pinus halepensis, estan sotmesos a períodes amb condicions meteorològiques extremes d'altes temperatures i estrés hídric. Aquestes condicions, al costat de l'actual context d'emergència climàtica genera condicions ideals per als grans incendis forestals de proporcions catastròfiques amb greus conseqüències en la salut i el benestar de les persones. En aquest context, una de les disciplines de coneixement científic que a penes s'han investigat fins hui en relació amb el risc d'incendis forestals és l'electrofisiologia vegetal. Per això, en la present tesi s'exposa l'avaluació experimental dels senyals elèctrics vegetals com a possibles variables equivalents de l'estat fenològic en els models de gestió, com a base per al futur desenvolupament de sistemes de xarxes de sensors sense fils, tot això a través de l'anàlisi de les característiques estàtiques i dinàmiques dels senyals electrofisiològics de la principal espècie arbòria de la conca mediterrània occidental, el Pinus halepensis. La tesi s'ha estructurat en tres capítols, seguint cadascun d'ells el mètode científic. En el primer capítol s'analitza l'avaluació d'alguns dels factors estàtics més significatius que influeixen en el patró de distribució dels senyals electrofisiològics del Pinus halepensis. Després d'un disseny mostral adequat, els resultats demostren que la maduresa de l'arbre influeix directament en la tensió elèctrica determinada per la tensió mesurada, sent els arbres joves els que presenten una major amplitud en el senyal elèctric, la qual es mostra uniforme en l'arbre, sent independent de la col·locació dels elèctrodes en altura i en orientació cardinal. En el segon capítol s'analitza l'evolució temporal del senyal elèctric registrat, tant diària com anual. Els resultats obtinguts demostren que els senyals electrofisiològics presenten valors significativament més alts i de major amplitud durant els períodes més humits amb temperatures moderades, mentre que els senyals són representativament molt més baixes, durant els períodes amb major estrés vegetatiu de l'any. La metodologia aplicada i els resultats aconseguits en aquest capítol de la tesi demostren que els senyals electrofisiològics poden ser considerades un indicador de l'estat fisiològic dels arbres en situacions d'estrés vegetatiu. Finalment, en el tercer capítol de la tesi s'analitza l'avaluació dels senyals electrofisiològics com a variables a incloure en els models de gestió del risc d'incendi forestal. Els resultats aconseguits ens han permés demostrar que el LFMC del Pinus halepensis no mostra variacions estacionals significatives sota la influència de factors extrems de risc d'incendi, mentre que les diferències registrades en els senyals electrofisiològics mostren oscil·lacions amb variacions significatives, que estan fortament correlacionades amb els períodes de condicions meteorològiques extremadament favorables per als incendis forestals. Finalment, també s'ha pogut demostrar una molt alta correlació entre les tensions mesurades i el principal índex de risc d'incendi utilitzats per les agències d'emergències Amb tots els resultats aconseguits, podem concloure finalment que les variacions en els senyals electrofisiològics estan estretament relacionades amb l'estat fenològic dels Pinus halepensis i amb el risc d'incendi forestal. El que obri la possibilitat d'un monitoratge in situ de les masses forestals en les quals domina aquesta espècie, la qual cosa seria fàcilment integrable en els sistemes de modelització i gestió preventiva dels incendis forestals en els ecosistemes mediterranis. / [EN] Pinus halepensis forests are subjected to periods of extreme weather conditions of high temperatures and water stress. These conditions, together with the current context of climatic emergency, generate ideal conditions for large forest fires of catastrophic proportions with serious consequences on the health and welfare of people. In this context, one of the disciplines of scientific knowledge that has hardly been investigated to date in relation to the risk of forest fires is plant electrophysiology. Therefore, this thesis presents the experimental evaluation of plant electrical signals as possible equivalent variables of the phenological state in management models, as a basis for the future development of wireless sensor network systems, all through the analysis of the static and dynamic characteristics of the electrophysiological signals of the main tree species of the western Mediterranean basin, Pinus halepensis. The thesis has been structured in three chapters, each of them following the scientific method. In the first chapter, the evaluation of some of the most significant static factors that influence the distribution pattern of electrophysiological signals in Pinus halepensis is analyzed. After an adequate sample design, the results show that the maturity of the tree directly influences the electrical voltage determined by the measured voltage, being the young trees those that present a greater amplitude in the electrical signal, which is uniform in the tree, being independent of the placement of the electrodes in height and in cardinal orientation. In the second chapter, the temporal evolution of the electrical signal recorded, both daily and annual, is analyzed. The results obtained show that the electrophysiological signals present significantly higher values and greater amplitude during the wettest periods with moderate temperatures, while the signals are representatively much lower during the periods with greater vegetative stress of the year. The methodology applied and the results obtained in this chapter of the thesis demonstrate that electrophysiological signals can be considered an indicator of the physiological state of trees in situations of vegetative stress. Finally, the third chapter of the thesis analyzes the evaluation of electrophysiological signals as variables to be included in wildfire risk management models. The results obtained have allowed us to demonstrate that the LFMC of Pinus halepensis does not show significant seasonal variations under the influence of extreme fire risk factors, while the differences recorded in the electrophysiological signals show oscillations with significant variations, which are strongly correlated with periods of extremely favorable meteorological conditions for forest fires. Finally, it has also been possible to demonstrate a very high correlation between the measured voltages and the main fire risk index used by emergency agencies. With all the results obtained, we can finally conclude that variations in electrophysiological signals are closely related to the phenological state of Pinus halepensis and to the risk of forest fire. This opens up the possibility of in situ monitoring of forest stands dominated by this species, which could be easily integrated into systems for modeling and preventive management of forest fires in Mediterranean ecosystems. / Zapata Zapata, R. (2023). Análisis de las señales electrofisiológicas en Pinus halepensis Mill como base a su aplicación en sensores inalámbricos para la prevención de incendios forestales [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/197905 / Compendio
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Developing a 2D Forest Fire Spread Simulation for Enhanced Decision-Making During Catastrophes in Sweden

Gauffin Dahlin, David January 2024 (has links)
This thesis presents the development and evaluation of a 2D simulation model designed to predict the spread and behavior of forest fires, with a specific focus on Swedish forest ecosystems. Despite the model's simplicity and inherent limitations due to assumptions such as homogeneity in fuel distribution and the exclusion of topographical influences, the simulations yield remarkably accurate predictions of fire spread and intensity. The model integrates basic meteorological data (wind speed and direction, temperature) and uses a discretized spatial approach to simulate the dynamics of forest fires. Initial results suggest that even with minimal input variables and broad assumptions, the model offers significant predictive capabilities, highlighting potential areas for future refinement. Key aspects such as the interaction between conduction and advection terms, the role of water vaporization in fire dynamics, and the influence of wind on fire propagation are discussed. The findings encourage further development of the model, aiming at incorporating more complex variables such as topography and more forest fuels, potentially enhancing its utility in real-time fire management and decision-making processes.

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