776 resultados para reconnaissance


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Les personnes salariées assurant le travail ménager au domicile des particuliers demeure le plus souvent considérées comme femmes de ménage et non comme professionnelles. Elles réalisent des tâches que tout le monde pense être en mesure d'effectuer et répondent cependant tant aux besoins d'une population vieillissante que de celle active. Cette recherche explore, dans une approche comparative, le contexte de travail des préposés au Québec et agents et employés de ménage en France ainsi que les apprentissages leur permettant d'exercer leur activité. Elle interroge également la relation entre ces apprentissages, la reconnaissance et la professionnalisation.

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Pour respecter les droits d’auteur, la version électronique de ce mémoire a été dépouillée de certains documents visuels et audio-visuels. La version intégrale du mémoire a été déposée au Service de la gestion des documents et des archives de l'Université de Montréal.

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Cet article concerne les barrages romains en terre du district de Castelo Branco qui ont été l'objet de récentes recherches des auteurs dans le cadre d'une plus vaste étude : Barragens Romanas do Distrito de Castelo Branco e Barragem de Alferrarede (Barrages romains du district de Castelo Branco et Barrage d'Alferrarede). Parmi les barrages étudiés, certains ont déjà été mentionnés par les auteurs.

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O século XXI introduziu profundas mudanças no espaço onde a atuação militar se desenvolve. Esta mutação, que agora inclui o domínio físico e cognitivo na ação militar, impõe a adoção de novos conceitos de operação e estruturas organizacionais mais ágeis, de forma a fazerem face a um ambiente altamente volátil, imprevisível e complexo. Tal contexto torna as organizações, hoje mais do que nunca, dependentes de informação (e dos sistemas que as geram), e no âmbito das organizações militares, uma capacidade em particular assume, na atualidade, uma preponderância fulcral para o sucesso destas, que se designa por Intelligence, Surveillance & Reconnaissance (ISR). Considerando a complexidade de sistemas, processos e pessoas que envolvem toda esta capacidade, torna-se relevante estudar como a Força Aérea Portuguesa (FAP) está a acomodar este conceito no interior da sua estrutura, uma vez que a sua adaptação requer uma organização da era da informação, onde o trabalho em rede assume particular destaque. A presente investigação analisa formas de estruturas organizacionais contemporâneas e cruza-as com as recomendações da Organização do Tratado do Atlântico Norte (também designada por Aliança), comparando-as posteriormente com a atualidade da FAP. No final, são efetuadas propostas tangíveis, que podem potenciar as capacidades existentes, de onde se destaca a criação de uma matriz de análise quanto à eficiência organizacional, uma nova forma de organização das capacidades residentes no que ao ISR concerne, bem como o modo de potenciar o trabalho em rede com base nos meios existentes. Abstract: The 21st century has caused profound changes in the areas where military action takes place. This mutation, which now includes the physical and cognitive domain in military action, requires the adoption of new concepts of operation and more agile organizational structures in order to cope with a highly volatile, unpredictable and complex environment. Thus, more than ever, this makes the present organizations dependent of information (and the systems that generate them), in the case of military organizations, a particular capability undertakes today a strong impact on the success of military organizations. It is known as Intelligence, Surveillance& Reconnaissance (ISR). Taking into account the complexity of systems, processes and people involving all this capability, it is relevant to study how the Portuguese Air Force (PAF) is accommodating this concept within its structure, since the adaptation requires an organization adapted to the information era, where networking is particularly prominent. This research aims to analyze contemporary forms of organizational structures and cross them with the recommendations of the North Atlantic Treaty Organization (also known as Alliance), later comparing them with today's PAF. At the end of this investigation, some tangible proposals are made which can enhance existing capabilities: we can highlight the creation of an analysis matrix for organizational efficiency, a new form of organization of the resident capabilities in the ISR concerns, as well as the way of enhancing networking, based on existing means.

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Over recent years, Unmanned Air Vehicles or UAVs have become a powerful tool for reconnaissance and surveillance tasks. These vehicles are now available in a broad size and capability range and are intended to fly in regions where the presence of onboard human pilots is either too risky or unnecessary. This paper describes the formulation and application of a design framework that supports the complex task of multidisciplinary design optimisation of UAVs systems via evolutionary computation. The framework includes a Graphical User Interface (GUI), a robust Evolutionary Algorithm optimiser named HAPEA, several design modules, mesh generators and post-processing capabilities in an integrated platform. These population –based algorithms such as EAs are good for cases problems where the search space can be multi-modal, non-convex or discontinuous, with multiple local minima and with noise, and also problems where we look for multiple solutions via Game Theory, namely a Nash equilibrium point or a Pareto set of non-dominated solutions. The application of the methodology is illustrated on conceptual and detailed multi-criteria and multidisciplinary shape design problems. Results indicate the practicality and robustness of the framework to find optimal shapes and trade—offs between the disciplinary analyses and to produce a set of non dominated solutions of an optimal Pareto front to the designer.

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In recent years, development of Unmanned Aerial Vehicles (UAV) has become a significant growing segment of the global aviation industry. These vehicles are developed with the intention of operating in regions where the presence of onboard human pilots is either too risky or unnecessary. Their popularity with both the military and civilian sectors have seen the use of UAVs in a diverse range of applications, from reconnaissance and surveillance tasks for the military, to civilian uses such as aid relief and monitoring tasks. Efficient energy utilisation on an UAV is essential to its functioning, often to achieve the operational goals of range, endurance and other specific mission requirements. Due to the limitations of the space available and the mass budget on the UAV, it is often a delicate balance between the onboard energy available (i.e. fuel) and achieving the operational goals. This thesis presents an investigation of methods for increasing the energy efficiency on UAVs. One method is via the development of a Mission Waypoint Optimisation (MWO) procedure for a small fixed-wing UAV, focusing on improving the onboard fuel economy. MWO deals with a pre-specified set of waypoints by modifying the given waypoints within certain limits to achieve its optimisation objectives of minimising/maximising specific parameters. A simulation model of a UAV was developed in the MATLAB Simulink environment, utilising the AeroSim Blockset and the in-built Aerosonde UAV block and its parameters. This simulation model was separately integrated with a multi-objective Evolutionary Algorithm (MOEA) optimiser and a Sequential Quadratic Programming (SQP) solver to perform single-objective and multi-objective optimisation procedures of a set of real-world waypoints in order to minimise the onboard fuel consumption. The results of both procedures show potential in reducing fuel consumption on a UAV in a ight mission. Additionally, a parallel Hybrid-Electric Propulsion System (HEPS) on a small fixedwing UAV incorporating an Ideal Operating Line (IOL) control strategy was developed. An IOL analysis of an Aerosonde engine was performed, and the most efficient (i.e. provides greatest torque output at the least fuel consumption) points of operation for this engine was determined. Simulation models of the components in a HEPS were designed and constructed in the MATLAB Simulink environment. It was demonstrated through simulation that an UAV with the current HEPS configuration was capable of achieving a fuel saving of 6.5%, compared to the ICE-only configuration. These components form the basis for the development of a complete simulation model of a Hybrid-Electric UAV (HEUAV).

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This study investigated potential palaeoclimate proxies provided by rare earth element (REE) geochemistry in speleothems and in clay mineralogy of cave sediments. Speleothem and sediment samples were collected from a series of cave fill deposits that occurred with rich vertebrate fossil assemblages in and around Mount Etna National Park, Rockhampton (central coastal Queensland). The fossil deposits range from Plio- Pleistocene to Holocene in age (based on uranium/thorium dating) and appear to represent depositional environments ranging from enclosed rainforest to semi-arid grasslands. Therefore, the Mount Etna cave deposits offer the perfect opportunity to test new palaeoclimate tools as they include deposits that span a known significant climate shift on the basis of independent faunal data. The first section of this study investigates the REE distribution of the host limestone to provide baseline geochemistry for subsequent speleothem investigations. The Devonian Mount Etna Beds were found to be more complex than previous literature had documented. The studied limestone massif is overturned, highly recrystallised in parts and consists of numerous allochthonous blocks with different spatial orientations. Despite the complex geologic history of the Mount Etna Beds, Devonian seawater-like REE patterns were recovered in some parts of the limestone and baseline geochemistry was determined for the bulk limestone for comparison with speleothem REE patterns. The second part of the study focused on REE distribution in the karst system and the palaeoclimatic implications of such records. It was found that REEs have a high affinity for calcite surfaces and that REE distributions in speleothems vary between growth bands much more than along growth bands, thus providing a temporal record that may relate to environmental changes. The morphology of different speleothems (i.e., stalactites, stalagmites, and flowstones) has little bearing on REE distributions provided they are not contaminated with particulate fines. Thus, baseline knowledge developed in the study suggested that speleothems were basically comparable for assessing palaeoclimatically controlled variations in REE distributions. Speleothems from rainforest and semi-arid phases were compared and it was found that there are definable differences in REE distribution that can be attributed to climate. In particular during semiarid phases, total REE concentration decreased, LREE became more depleted, Y/Ho increased, La anomalies were more positive and Ce anomalies were more negative. This may reflect more soil development during rainforest phases and more organic particles and colloids, which are known to transport REEs, in karst waters. However, on a finer temporal scale (i.e. growth bands) within speleothems from the same climate regime, no difference was seen. It is suggested that this may be due to inadequate time for soil development changes on the time frames represented by differences in growth band density. The third part of the study was a reconnaissance investigation focused on mineralogy of clay cave sediments, illite/kaolinite ratios in particular, and the potential palaeoclimatic implications of such records. Although the sample distribution was not optimal, the preliminary results suggest that the illite/kaolinite ratio increased during cold and dry intervals, consistent with decreased chemical weathering during those times. The study provides a basic framework for future studies at differing latitudes to further constrain the parameters of the proxy. The identification of such a proxy recorded in cave sediment has broad implications as clay ratios could potentially provide a basic local climate proxy in the absence of fossil faunas and speleothem material. This study suggests that REEs distributed in speleothems may provide information about water throughput and soil formation, thus providing a potential palaeoclimate proxy. It highlights the importance of understanding the host limestone geochemistry and broadens the distribution and potential number of cave field sites as palaeoclimate information no longer relies solely on the presence of fossil faunas and or speleothems. However, additional research is required to better understand the temporal scales required for the proxies to be recognised.

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Aerial Vehicles (UAV) has become a significant growing segment of the global aviation industry. These vehicles are developed with the intention of operating in regions where the presence of onboard human pilots is either too risky or unnecessary. Their popularity with both the military and civilian sectors have seen the use of UAVs in a diverse range of applications, from reconnaissance and surveillance tasks for the military, to civilian uses such as aid relief and monitoring tasks. Efficient energy utilisation on an UAV is essential to its functioning, often to achieve the operational goals of range, endurance and other specific mission requirements. Due to the limitations of the space available and the mass budget on the UAV, it is often a delicate balance between the onboard energy available (i.e. fuel) and achieving the operational goals. This paper presents the development of a parallel Hybrid Electric Propulsion System (HEPS) on a small fixed-wing UAV incorporating an Ideal Operating Line (IOL) control strategy. A simulation model of an UAV was developed in the MATLAB Simulink environment, utilising the AeroSim Blockset and the in-built Aerosonde UAV block and its parameters. An IOL analysis of an Aerosonde engine was performed, and the most efficient (i.e. provides greatest torque output at the least fuel consumption) points of operation for this engine were determined. Simulation models of the components in a HEPS were designed and constructed in the MATLAB Simulink environment. It was demonstrated through simulation that an UAV with the current HEPS configuration was capable of achieving a fuel saving of 6.5%, compared to the ICE-only configuration. These components form the basis for the development of a complete simulation model of a Hybrid-Electric UAV (HEUAV).

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An onboard payload may be seen in most instances as the “Raison d’Etre” for a UAV. It will define its capabilities, usability and hence market value. Large and medium UAV payloads exhibit significant differences in size and computing capability when compared with small UAVs. The latter have stringent size, weight, and power requirements, typically referred as SWaP, while the former still exhibit endless appetite for compute capability. The tendency for this type of UAVs (Global Hawk, Hunter, Fire Scout, etc.) is to increase payload density and hence processing capability. An example of this approach is the Northrop Grumman MQ-8 Fire Scout helicopter, which has a modular payload architecture that incorporates off-the-shelf components. Regardless of the UAV size and capabilities, advances in miniaturization of electronics are enabling the replacement of multiprocessing, power-hungry general-purpose processors for more integrated and compact electronics (e.g., FPGAs). Payloads play a significant role in the quality of ISR (intelligent, surveillance, and reconnaissance) data, and also in how quick that information can be delivered to the end user. At a high level, payloads are important enablers of greater mission autonomy, which is the ultimate aim in every UAV. This section describes common payload sensors and introduces two examples cases in which onboard payloads were used to solve real-world problems. A collision avoidance payload based on electro optical (EO) sensors is first introduced, followed by a remote sensing application for power line inspection and vegetation management.

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This report presents observations, findings, and recommendations from an engineering reconnaissance trip following the May 20th, 2013 tornado that struck Moore, Oklahoma. A team of faculty, research scientists, professional engineers, and civil engineering students were tasked with investigating and documenting the performance of critical facility buildings and residences, (IBC Occupancy Category II, III, and IV), in Moore, OK. The Enhanced Fujita (EF) 5 tornado created a 17-mile long damage swath destroying over 12,000 buildings and killing 24 people. The total economic loss from this single event was estimated at $3 billion. The May 20th tornado was the third major tornado to hit Moore in the previous 15 years.

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In this paper, we present the design and development details of a micro air vehicle (MAV) built around a quadrotor configuration. A survey of implemented MAVs suggests that a quadrotor design has several advantages over other configurations, especially in the context of swarm intelligence applications. Our design approach consists of three stages. However, the focus of this paper is restricted to the first stage that involves selection of crucial components such as motor-rotor pair, battery source, and structural material. The application of MAVs are broad-ranging, from reconnaissance to search and rescue, and have immense potential in the rapidly advancing field of swarm intelligence.

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Grouping and coordination tactics for ground attack missions by a heterogeneous mix of reconnaissance, enemy suppression, and attack unmanned aerial vehicles (UAVs) is presented. Dubins' paths are used to determine the optimal number of attack UAVs and their positional and heading freedoms, as functions of weapon seeker range and field of view. A generic battlefield scenario with layered defense is created and the tactics are evaluated on a Group Flyer simulation platform for both nominal and off-nominal conditions.

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Résumé: Le défi vital que la Révélation pose à la philosophie légitime la question de leurs rapports possibles. La raison considère d’abord l’absence de rapport en distinguant radicalement ce qui relève de chacune. Mais l’élan fondamental orienté vers le divin qui anime cette faculté, la rend naturellement théologique. Pour éviter le scepticisme, incompatible avec son dynamisme naturel, la raison finit par dévaloriser la Révélation. Cette attitude signifie l’unicité de l’autorité théologique de la raison, alors naturellement divine. Développée à partir du XVIIIème siècle, elle culmine avec l’homme démiurgique des XIX et XXème siècles. Mais, ne pouvant justifier l’universalité de ses élaborations idéologiques, la raison hésite entre le scepticisme ou le totalitarisme, deux renoncements à l’exercice philosophique. L’acceptation du soutien lumineux de la Révélation, qui suppose l’humble reconnaissance des limites de la raison, ne nuit pas à cet exercice, mais le féconde, et, seule, en permet l’épanouissement. Eclairée par la Révélation, la philosophie contribue au bonheur suprême des hommes, qui demeure son intention fondamentale.