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Stránský, Marek. "Měření povrchových teplot ve strojírenství." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231656.
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This work deals with contact and non-contact methods of surface temperature measurement. The work contains a list and formulations of basic terms and laws of thermodynamics. Furthermore, the work deals with the description and comparison of the properties and use of certain devices for contact and non-contact surface temperature measurement. The experimental part is focused on dependence of the turning speed on the turning knife thermal stress. Subsurface thermocouples, surface thermocouples and thermovision were used for the temperature detection. The subsurface temperatures were afterwards used (as data inputs) for the inverse calculation of surface temperatures. All results obtained were then compared to each other.
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Junior, Vladimir Geraseev. "Proposta de sistema automatizado para apoio à inspeção de termohigrômetros digitais específicos." Universidade de Taubaté, 2014. http://www.bdtd.unitau.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=761.
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Atualmente, há diversos modelos de instrumentos termohigrômetros, utilizados em grande variedade de aplicações nas organizações, cujas medições de temperatura e umidade relativa se fazem necessárias. Nas atividades referentes ao desenvolvimento, fabricação e utilização desses instrumentos, há a necessidade de inspeções funcionais neles, para avaliações sobre as medições proporcionadas. De forma pertinente ao exposto, neste trabalho, é apresentada abordagem sobre os elementos do projeto conceitual de um sistema que utiliza visão computacional para apoio à realização da inspeção de tipo específico de termohigrômetro digital, em operações que envolvem a leitura e o registro das medidas indicadas no instrumento, como parte do procedimento adotado para a inspeção em questão. O tipo de termohigrômetro digital abordado é caracterizado: por ser de indicação digital em única face do invólucro; possuir mostrador de cristal líquido com dígitos de sete segmentos e notação em ponto decimal; apresentar em regiões distintas os dados das medições simultâneas de temperatura e umidade relativa; por não dispor de recursos de comunicação para aquisição dos dados das medições. O projeto conceitual do sistema abordado é caracterizado por explorar conceitos da aplicação de recursos de aquisição de imagens e reconhecimento óptico de caracteres, com a finalidade de dispor imagens e dados em meios computacionais, de forma automatizada, para auxiliar as operações de leitura e registro das medidas indicadas no termohigrômetro sob inspeção, sendo as informações resultantes acessíveis por outros sistemas computacionais. Os componentes para experimentos apresentaram resultados satisfatórios nos testes práticos, validando os princípios de funcionamento dos elementos implementados, do sistema de inspeção e da aplicação. Os objetivos propostos foram atingidos, haja vista que os estudos expostos permitem oferecer contribuição para as atividades referentes ao desenvolvimento, fabricação e utilização de termohigrômetros do tipo em questão, com ênfase para o âmbito daquelas relacionadas aos segmentos das aplicações de sistemas computacionais, voltadas para automatizações de processos de inspeção desse tipo de instrumento, para as quais possam ser estendidos os conceitos abordados.Currently, there are many thermo hygrometer instruments that are used in several applications in organizations in which measurements of temperature and relative humidity are required. In order to verify the measurements provided by these instruments, it is necessary to perform functional inspection tests in them, in development, manufacture and usage activities, in order to verify the measurements provided by these instruments. In this paper, an approach of the elements used in a conceptual system using computer vision to support digital thermo hygrometer inspection is presented. The computer vision is used in operations that involve reading and recording of measurements in the instrument as part of the procedure adopted for their inspection. The kind of digital thermo hygrometer addressed in this paper is a digital instrument, with a liquid crystal display using seven-segment digits and a decimal point notation, which shows simultaneous measurements of temperature and relative humidity in different locations of its display, and which doesnt have communication resources for reading the measurement data. The system conceptual design explores concepts that use resources for acquiring images and for optical character recognition, in order to automatically provide images and data in a computer media, and assist the operations of reading and recording measures indicated by the thermo hygrometer. The resulting information can be accessible by other computer systems. The components used for experiments presented satisfactory results in practical tests, validating the principles of operation of the implemented elements of the inspection system and application. The proposed objectives were achieved, given the fact that the studies exposed here make it possible to offer assistance to activities related to the development, manufacture and use of thermo hygrometers of the type in question, with emphasis on those related to the scope of segments of applications for computing systems oriented to the automation of inspection processes of this type of instrument, for which the concepts covered may be extended.
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Neo, Tiong Tien. "Fusion of night vision and thermal images." Thesis, Monterey, Calif. : Naval Postgraduate School, 2006. http://bosun.nps.edu/uhtbin/hyperion.exe/06Dec%5FNeo.pdf.
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Thesis (M.S. in Combat Systems Science and Technology)--Naval Postgraduate School, December 2006.Thesis Advisor(s): Monique P. Fargues, Alfred W. Cooper. "December 2006." Includes bibliographical references (p.113-116). Also available in print.
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Bombrun, Maxime. "Characterisation of volcanic emissions through thermal vision." Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22600/document.
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En avril 2010, l’éruption de l’Eyjafjallajökull (Islande) a projeté des cendres sur toute l’Europe pendant six jours, causant d’importantes perturbations aériennes. Cette crise a soulevé la nécessité de mieux comprendre la dynamique des panaches lors de l’émission, de la dispersion, et de la retombée afin d’améliorer les modèles de suivis et de prédiction de ces phénomènes. Cette éruption a été classée comme Strombolienne. Ce type d’éruption offre un large panel de manifestations (coulée de lave, paroxysmes) et peut être utilisé comme indicateur d’éruptions plus dangereuses. Les éruptions stromboliennes permettent généralement une observation à quelques centaines de mètres tout en assurant la sécurité des opérateurs et du matériel. Depuis 2001, les caméras thermiques ont été de plus en plus utilisées pour comprendre la dynamique des évènements volcaniques. Toutefois, l’analyse, la modélisation et le post-traitement de ces données thermiques n’est toujours pas totalement informatisé. Durant ma thèse, j’ai étudié les différentes composantes d’une éruption strombolienne depuis les fines particules éjectées au niveau du cratère jusqu’à la vision d’ensemble offerte par les images satellites. Dans l’ensemble, j’ai caractérisé les émissions volcaniques à travers l’imagerie thermiqueIn April 2010, the eruption of Eyjafjallajökull (Iceland) threw volcanic ash across northwest Europe for six days which led to air travel disruption. This recent crisis spotlighted the necessity to parameterise plume dynamics through emission, dispersion and fall out as to better model, track and forecast cloud motions. This eruption was labeled as a Strombolian-to-Sub-Plinian eruption type. Strombolian eruptions are coupled with a large range of volcanic event types (Lava flows, paroxysms) and eruption styles (Hawaiian, Sub-plinian) and offer a partial precursory-indicator of more dangerous eruptions. In addition, strombolian eruptions are small enough to allow observations from within few hundred meters with relative safety, for both operators and material. Since 2001, thermal cameras have been increasingly used to track, parameterise and understand dynamic volcanic events. However, analyses, modelling and post-processing of thermal data are still not fully automated. In this thesis, I focus on the different components of strombolian eruptions at the full range of remote sensing spatial scales. These range from millimeters for particles to kilometers for the entire features via satellite images. Overall, I aim to characterise volcanic emissions through thermal vision
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Teo, Chek Koon. "Digital enhancement of night vision and thermal images." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Dec%5FTeo%5FChek.pdf.
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Thesis (M.S. in Combat Systems Technology)--Naval Postgraduate School, December 2003.Thesis advisor(s): Monique P. Fargues, Alfred W. Cooper. Includes bibliographical references (p. 75-76). Also available online.
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Roychoudhury, Shoumik. "Tracking Human in Thermal Vision using Multi-feature Histogram." Master's thesis, Temple University Libraries, 2012. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/203794.
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Electrical EngineeringM.S.E.E.
This thesis presents a multi-feature histogram approach to track a person in thermal vision. Illumination variation is a primary constraint in the performance of object tracking in visible spectrum. Thermal infrared (IR) sensor, which measures the heat energy emitted from an object, is less sensitive to illumination variations. Therefore, thermal vision has immense advantage in object tracking in varying illumination conditions. Kernel based approaches such as mean shift tracking algorithm which uses a single feature histogram for object representation, has gained popularity in the field of computer vision due its efficiency and robustness to track non-rigid object in significant complex background. However, due to low resolution of IR images the gray level intensity information is not sufficient enough to give a strong cue for object representation using histogram. Multi-feature histogram, which is the combination of the gray level intensity information and edge information, generates an object representation which is more robust in thermal vision. The objective of this research is to develop a robust human tracking system which can autonomously detect, identify and track a person in a complex thermal IR scene. In this thesis the tracking procedure has been adapted from the well-known and efficient mean shift tracking algorithm and has been modified to enable fusion of multiple features to increase the robustness of the tracking procedure in thermal vision. In order to identify the object of interest before tracking, rapid human detection in thermal IR scene is achieved using Adaboost classification algorithm. Furthermore, a computationally efficient body pose recognition method is developed which uses Hu-invariant moments for matching object shapes. An experimental setup consisting of a Forward Looking Infrared (FLIR) camera, mounted on a Pioneer P3-DX mobile robot platform was used to test the proposed human tracking system in both indoor and uncontrolled outdoor environments. The performance evaluation of the proposed tracking system on the OTCBVS benchmark dataset shows improvement in tracking performance in comparison to the traditional mean-shift tracking algorithm. Moreover, experimental results in different indoor and outdoor tracking scenarios involving different appearances of people show tracking is robust under cluttered background, varying illumination and partial occlusion of target object.
Temple University--Theses
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Cielniak, Grzegorz. "People Tracking by Mobile Robots using Thermal and Colour Vision." Doctoral thesis, Örebro : Örebro universitetsbibliotek, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-1111.
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Zhang, Lichang. "Non-invasive detection algorithm of thermal comfort based on computer vision." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-241082.
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The waste of building energy consumption is a major challenge in the world. And the real-time detection of human thermal comfort is an effective way to meet this issue. As mentioned in name, it means to detect the human’s comfort level in real-time and non-invasively. However, due to the various factors such as individual difference of thermal comfort, elements related to climatic (temperature, humidity, illumination, etc.) and so on, there is still a long way to implement this strategy in real life. From another perspective, the current HVAC (heating, ventilating and air-conditioning) systems cannot provide flexible interaction channels to adjust atmosphere, and naturally fails to satisfy requirements of users. All of them indicate the necessity to develop a detection method for human thermal comfort. In this paper, a non-invasion detection method toward human thermal comfort is proposed from two perspectives: macro human postures and skin textures. In posture part, OpenPose is used for analyzing the position coordinates of human body key points’ in images, for example, elbow, knee, and hipbone, etc. And the results of analyzing would be interpreted from the term of thermal comfort. In skin textures, deep neural network is used to predict the temperature of human skins via images. Based on Fanger’s theory of thermal comfort, the results of both parts are satisfying: subjects’ postures can be captured and interpreted into different thermal comfort level: hot, cold and comfort. And the absolute error of prediction from neurons network is less than 0.125 degrees centigrade which is the equipment error of thermometer used in data acquisition. With the solution proposed by this paper, it is promising to non-invasively detect the thermal comfort level of users from postures and skin textures. Finally, theconclusion and future work are discussed in final chapter.Slöseriet med att bygga energiförbrukningen är en stor utmaning i världen. Ochdetektering av mänsklig termisk komfort i realtid är ett effektivt sätt att lösaproblemet. Som nämns i namn betyder det att detektera människans komfortnivå i realtid och icke-invasivt. På grund av de olika faktorerna som individuell skillnad i termisk komfort, är emellertid faktorer som är relaterade till klimat (temperatur, luftfuktighet, belysning etc.) det fortfarande en lång väg att implementera denna strategi i verkligheten. Från ett annat perspektiv kan nuvarande system för uppvärmning, ventilation och luftkonditionering inte tillhandahålla flexibla interaktionskanaler för att anpassa atmosfären och naturligtvis misslyckas till nöjda krav från användarna. Alla indikerar nödvändigheten av att utveckla en detekteringsmetod för mänsklig termisk komfort. I detta dokument föreslås en ickeinvasion detekteringsmetod mot mänsklig termisk komfort från två perspektiv: makro mänskliga hållningar och hudtexturer. I hållningspartiet används OpenPose för att analysera positionskoordinaterna för kroppens huvudpunkter i bilder, till exempel armbåge, knä och höftben osv. Och resultaten av analysen skulle tolkas från termen av termisk komfort. I hudtexturer används djupt neuralt nätverk för att förutse temperaturen på mänskliga skinn via bilder. Baserat på Fangers teorin om värmekomfort är resultaten av båda delarna tillfredsställande: subjektens hållningar kan fångas och tolkas till olika värmekomfortnivåer: varm, kall och komfort. Och det absoluta felet av prediktering från neuronnätverket är mindre än 0,125 grader Celsius, vilket är utrustningsfelet hos termometern som används vid datainsamling. Med lösningar i detta papper är det lovande att detektera användarens värmekomfortnivå fritt från invändningar och hudtexturer. Slutligen diskuteras slutsatserna och detframtida arbetet i sista kapitlet.
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Sun, Roy. "Pedestrian Detection Based on Data and Decision Fusion Using Stereo Vision and Thermal Imaging." Digital WPI, 2016. https://digitalcommons.wpi.edu/etd-theses/308.
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Pedestrian detection is a canonical instance of object detection that remains a popular topic of research and a key problem in computer vision due to its diverse applications. These applications have the potential to positively improve the quality of life. In recent years, the number of approaches to detecting pedestrians in monocular and binocular images has grown steadily. However, the use of multispectral imaging is still uncommon. This thesis work presents a novel approach to data and feature fusion of a multispectral imaging system for pedestrian detection. It also includes the design and building of a test rig which allows for quick data collection of real-world driving. An application of the mathematical theory of trifocal tensor is used to post process this data. This allows for pixel level data fusion across a multispectral set of data. Performance results based on commonly used SVM classification architectures are evaluated against the collected data set. Lastly, a novel cascaded SVM architecture used in both classification and detection is discussed. Performance improvements through the use of feature fusion is demonstrated.
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Shi, Jie. "Obstacle detection using thermal imaging sensors for large passenger airplane." Thesis, Cranfield University, 2012. http://dspace.lib.cranfield.ac.uk/handle/1826/7944.
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This thesis addresses the issue of ground collision in poor weather conditions. As bad weather is an adverse factor when airplanes are taxiing, an obstacle detection system based on thermal vision is proposed to enhance the awareness of pilots during taxiing in poor weather conditions. Two infrared cameras are employed to detect the objects and estimate the distance of the obstacle. The distance is computed by stereo vision technology. A warning will be given if the distance is less than the safe distance predefined. To make the system independent, the proposed system is an on-board system which does not rely on airports or other airplanes.
The type of obstacle is classified by the temperature of the object. Fuzzy logic is employed in the classification. Obstacles are classified into three main categories: aircraft, vehicle and people. Membership functions are built based on the temperature distribution of obstacles measured at the airport. In order to improve the accuracy of classification, a concept of using position information is proposed. Different types of obstacle are predefined according to different area at the airport. In the classification, obstacles are classified according to the types limited in that area.
Due to the limitation of the thermal infrared camera borrowed, images were captured first and then processed offline. Experiments were carried out to evaluate the detecting distance error and the performance of system in poor weather conditions. The classification of obstacle is simulated with real thermal images and pseudo position information at the airport. The results suggest that the stereo vision system developed in this research was able to detect the obstacle and estimate the distance. The classification method classified the obstacles to a certain extent. Therefore, the proposed system can improve safety of aircraft and enhance situational awareness of pilots.
The programming language of the system is Python 2.7. Computer graphic library OpenCV 2.3 is used in processing images. MATLAB is used in the simulation of obstacle classification.
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Al, Alwani Adnan Salih. "Event and action recognition from thermal and 3D depth Sensing." Caen, 2016. http://www.theses.fr/2016CAEN2003.
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On assiste depuis quelques temps `a un regain d’intérêt pour un certain nombre de problèmes liés au domaine de l’analyse de l’activité humaine `a partir de caméras et de capteurs 3D et ceci pour plusieurs raisons dont principalement le d´développement de la technologie d’estimation de profondeur de Kinect et les caméras Time-Of-Flight. En outre, le caractère complémentaire de la profondeur et de l’information visuelle (RGB) fournies par ces dispositifs offre de nouvelles solutions potentielles aux problèmes classiques de la vision par ordinateur. Par ailleurs, la thermographie infrarouge (IRT), aussi connu comme l’imagerie thermique, est une technologie idéale pour garantir des résultats de mesures non intrusives probants en toutes circonstances pour un nombre croissant d’applications de s´écrite et de surveillance comme pour le diagnostic m´médical. L’analyse thermique affine la reconnaissance visuelle. Cependant, d´détecter `a la volée un ´évènement remarquable qui se distingue par son comportement temporel, dans les s´séquences vidéo reste un d´défi majeure. Ce problème est particulièrement difficile en raison d’´énormes variations dans les aspects visuels et de mouvement des objets et de la caméra, des occlusions, ainsi que la présence de bruit. L’objectif principal de cette thèse est d’apporter des contributions m´méthodologiques pour la d´détection des ´évènements `a partir de flux issus de caméras thermique et de caméras de profondeur Kinect. La première partie de nos contributions concerne le d´développement d’une plateforme de reconnaissance d’´évènement thermique basée sur l’extraction de motifs spatio-temporels `a partir de s´séries chronologiques avec une application d´ediee au domaine m´médical. Nous nous sommes intéresses particulièrement `a la d´détection de la douleur chez les bébés prématurés et nous avons introduit une nouvelle base de données (Pretherm) réalisée dans le cadre du projet ANR du même nom, avec des vidéos de bébés prématurés de l’hôpital CHU de Caen. Pour caractériser le motif d’intérêt dans un signal monodimensionnel, nous avons proposé d’utiliser un descripteur basé sur les motifs binaires locaux non redondants (ou résiduels). Nous avons ´également d´défini une nouvelle m´méthode basée sur la persistance topologique pour filtrer et ordonner les valeurs critiques. Les deux m´méthodes ont ´et´e validés sur le corpus de s´séquences thermiques représentant la douleur et non douleur chez les enfants prématurés, grâce aux m´méthodes d’apprentissage statistique automatique suivants : Les réseaux de neurones (avec Extreme Learning Machines) et les m´méthodes a noyaux (avec Support Vector Machines). Dans la seconde partie de la thèse, nous avons ´étudie le problème de la reconnaissance automatique d’action humaine `a partir de caméras `a capteur de profondeur type Kinect. Nous nous sommes concentrés sur le d´développement de descripteurs spatio-temporels pertinents qui caractérisent au mieux l’action humaine et qui permettent de bien identifier la nature de l’action(classification). Nous passions en revue et comparions les techniques les plus populaires de l’´état de l’art pour la reconnaissance d’action. Dans un premier volet, nous nous sommes orient ´es vers l’analyse des angles des articulations et de leurs trajectoires. `a chaque angle d’articulation est associée une trajectoire au cours de l’action. La trajectoire d’une action donnée est ainsi d´décomposée en une suite de trajectoires ´élémentaires permettant la création d’un vocabulaire visuel compact et la construction d’un automate de reconnaissance d’actions modélise par un modèle de Markov caché (HMM). Pour pallier la sensibilité `a la rotation et aux variations locales des trajectoires, nous avons proposé une seconde approche basée sur les harmoniques sphériques (SHs). Ces derniers ´étant une description fréquentielle de l’image sphérique, le spectre est alors utilise comme descripteur, de structure de l’environnement dont la dimension est très faible, qui servira pour apprendre et reconnaitre les poses. Chaque catégorie est ainsi caractérisée par une distribution de probabilité de spectres d’harmoniques sphériques. Ensuite, pour améliorer la précision et la convergence des calculs, nous avons utilise une représentation compacte en utilisant les harmoniques sphériques sous une forme quadratique. Finalement, les techniques proposées permettent d’obtenir une performance meilleure ou semblable par rapport `a l’´etat de l’art, sur des bases de données représentant une grande diversité d’actions 3D (MSR Action 3D , UTKinect Action , Florence Action, et G3D)Modern computer vision algorithms try to understand the human activity using 3D visible sensors. However, there are inherent problems using 2D visible sensors as a data source. First, visible light images are sensitive to illumination changes and background clutter. Second, the 3D structural information of the scene is degraded when mapping the 3D scene to 2D images. Recently, the easy access to the RGBD data at real-time frame rate is leading to a revolution in perception and inspired many new research. Time of Flight (ToF) and multi-view sensors have been used to model the 3D structure of the scene. Otherwise, infrared thermography (IRT), also known as thermal imaging, is an ideal technology to investigate thermal anomalie under different circumstances because it provides complete thermal images of an object with no physical attachments (nonintrusive). IRT is now being introduced to a wide range of different applications, such as medical diagnostic and surveillance. However, finding meaningful features from a time series data from thermal video is still a challenging problem, especially for event detection. This problem is particularly hard due to enormous variations in visual and motion appearance of object, moving background, occlusions and thermal noise. In this thesis, we propose a framework for the detection of visual events in thermal video and 3d human actions in RGBD data. Despite differences in the applications, the associated fundamental problems share numerous properties, for instance the necessity of handling vision-based approach for the automatic recognition of events. The first part of the thesis deals with the recognition of events in thermal video. In this context, the use of time series is challenging due to the graphical nature which exposes hidden patterns and structural changes in data. In this study, we investigated the use of visual texture patterns for time series classification. Our principal aim was to develop a general framework for time series data mining based on event analysis with an application to the medical domain. In particular, we are interested to pain/no-pain detection using parametric statistics and shape descriptors in order to analyze and to classify time 2D distribution data sets. We first extracted automatically thermal-visual facial features from each face considered as the region of interest (ROI) of the image. We proposed two feature descriptors for the signal pattern of interest (POI) which efficiently exploits the dependence between time and frequency in one-dimension (1D) signal. The original signal is extracted directly from local patch in ROI. The first method is based on non-redundant temporal local binary pattern (NRTLBP). The second approach propose a topological persistence descriptor (TP) for extracting and filtering local extrema of 1D signal. Local minima and local maxima are extracted, paired, and sorted according to their persistence. The final representation of an event is a completely new feature vector of all paired critical values. These features provide many benefits for many applications to get a fast estimation of the event in dynamic time series data. Both methods are validated using an Extreme Learning Machine (ELM) and Support vector Machine (SVM) classifiers. Experimental results on a real thermal-based data set ”Pain in Preterm Infants” (PPI), which is captured in a real condition monitoring environment, show that the proposed methods successfully capture temporal changes in events and achieve higher recognition rates. PPI dataset was developed in the context of Infant pain project, a french project supported by the French National Research Agency Projects for science (ANR). _ In the second part of the thesis, we investigate the problem of recognizing human activities in different application scenarios: controlled video environment( e. G. Indoor surveillance) and specially depth or skeletal data (e. G. Captured by Kinect). We focus on developing spatio-temporal features, and applying these features to identify human activities from a sequence of RGB-D images, i. E. ,color images with depth information. First, we proposed a view-invariant approach which use joint angles and relative joint positions as features. These features are quantized into posture visual words and their temporal transitions are encoded as observation symbols in a Hidden Markov Model (HMM). To eliminate rotation dependence in skeletal descriptors, we proposed an approach that combines the covariance descriptor and the spherical harmonics (SHs). The harmonic representation of 3d shape descriptors is adapted to skeleton joint-based human action recognition. To improve the accuracy and the convergence speed of the SHs solutions, we proposed an extension of the model, using quadratic spherical harmonics (QSH) representation, to encode pose information in the spatiotemporal space. These SHs representations are compact and discriminating. For the recognition task, we used ELM classifier. Our experimental results on a number of popular 3d action datasets show significant achievements in terms of accuracy, scalability and efficiency in comparison to alternate methods, of the state-of-the-art
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Lu, Siliang. "Dynamic HVAC Operations Based on Occupancy Patterns With Real-Time Vision- Based System." Research Showcase @ CMU, 2017. http://repository.cmu.edu/theses/132.
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An integrated heating, ventilation and air-conditioning (HVAC) system is one of the most important components to determining the energy consumption of the entire building. For commercial buildings, particularly office buildings and schools, the heating and cooling loads are largely dependent on the occupant behavioral patterns such as occupancy rates and their activities. Therefore, if HVAC systems can respond to dynamic occupancy profiles, there is a large potential to reduce energy consumption. However, currently, most of existing HVAC systems operate without the ability to adjust supply air rate accordingly in response to the dynamic profiles of occupants. Due to this inefficiency, much of the HVAC energy use is wasted, particularly when the conditioned spaces are unoccupied or under-occupied (less occupants than the intended design). The solution to this inefficiency is to control HVAC system based on dynamic occupant profiles. Motivated by this, the research provides a real-time vision-based occupant pattern recognition system for occupancy counting as well as activity level classification. The proposed vision-based system is integrated into the existing HVAC simulation model of a U.S. office building to investigate the level of energy savings as well as thermal comfort improvement compared to traditional existing HVAC control system. The research is divided into two parts. The first part is to use an open source library based on neural network for real-time occupant counting and background subtraction method for activity level classification with a common static RGB camera. The second part utilizes a DOE reference office building model with customized dynamic occupancy schedule, including the number of occupant schedule, activity schedule and clothing insulation schedule to identify the potential energy savings compared with conventional HVAC control system. The research results revealed that vision-based systems can detect occupants and classify activity level in real time with accuracy around 90% when there are not many occlusions. Additionally, the dynamic occupant schedules indeed can bring about energy savings. Details of vision-based system, methodology, simulation configurations and results will be presented in the paper as well as potential opportunities for use throughout multiple types of commercial buildings, specifically focused on office and educational institutes.
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Nyberg, Adam. "Transforming Thermal Images to Visible Spectrum Images Using Deep Learning." Thesis, Linköpings universitet, Datorseende, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-151982.
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Thermal spectrum cameras are gaining interest in many applications due to their long wavelength which allows them to operate under low light and harsh weather conditions. One disadvantage of thermal cameras is their limited visual interpretability for humans, which limits the scope of their applications. In this thesis, we try to address this problem by investigating the possibility of transforming thermal infrared (TIR) images to perceptually realistic visible spectrum (VIS) images by using Convolutional Neural Networks (CNNs). Existing state-of-the-art colorization CNNs fail to provide the desired output as they were trained to map grayscale VIS images to color VIS images. Instead, we utilize an auto-encoder architecture to perform cross-spectral transformation between TIR and VIS images. This architecture was shown to quantitatively perform very well on the problem while producing perceptually realistic images. We show that the quantitative differences are insignificant when training this architecture using different color spaces, while there exist clear qualitative differences depending on the choice of color space. Finally, we found that a CNN trained from daytime examples generalizes well on tests from night time.
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Cheng, Wee Kiang. "Evaluation of Night Vision Devices for image fusion studies /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Dec%5FCheng%5Wee.pdf.
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Thesis (M.S. in Combat Systems Technology)--Naval Postgraduate School, Dec. 2004.Thesis Advisor(s): Alfred W Cooper, Gamani Karunasiri. Includes bibliographical references (p. 119-120). Also available online.
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Berg, Amanda. "Detection and Tracking in Thermal Infrared Imagery." Licentiate thesis, Linköpings universitet, Datorseende, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-126955.
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Thermal cameras have historically been of interest mainly for military applications. Increasing image quality and resolution combined with decreasing price and size during recent years have, however, opened up new application areas. They are now widely used for civilian applications, e.g., within industry, to search for missing persons, in automotive safety, as well as for medical applications. Thermal cameras are useful as soon as it is possible to measure a temperature difference. Compared to cameras operating in the visual spectrum, they are advantageous due to their ability to see in total darkness, robustness to illumination variations, and less intrusion on privacy. This thesis addresses the problem of detection and tracking in thermal infrared imagery. Visual detection and tracking of objects in video are research areas that have been and currently are subject to extensive research. Indications oftheir popularity are recent benchmarks such as the annual Visual Object Tracking (VOT) challenges, the Object Tracking Benchmarks, the series of workshops on Performance Evaluation of Tracking and Surveillance (PETS), and the workshops on Change Detection. Benchmark results indicate that detection and tracking are still challenging problems. A common belief is that detection and tracking in thermal infrared imagery is identical to detection and tracking in grayscale visual imagery. This thesis argues that the preceding allegation is not true. The characteristics of thermal infrared radiation and imagery pose certain challenges to image analysis algorithms. The thesis describes these characteristics and challenges as well as presents evaluation results confirming the hypothesis. Detection and tracking are often treated as two separate problems. However, some tracking methods, e.g. template-based tracking methods, base their tracking on repeated specific detections. They learn a model of the object that is adaptively updated. That is, detection and tracking are performed jointly. The thesis includes a template-based tracking method designed specifically for thermal infrared imagery, describes a thermal infrared dataset for evaluation of template-based tracking methods, and provides an overview of the first challenge on short-term,single-object tracking in thermal infrared video. Finally, two applications employing detection and tracking methods are presented.
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Wedberg, Magnus. "Detecting Rails in Images from a Train-Mounted Thermal Camera Using a Convolutional Neural Network." Thesis, Linköpings universitet, Datorseende, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-138523.
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Now and then train accidents occur. Collisions between trains and objects such as animals, humans, cars, and fallen trees can result in casualties, severe damage on the train, and delays in the train traffic. Thus, train collisions are a considerable problem with consequences affecting society substantially. The company Termisk Systemteknik AB has on commission by Rindi Solutions AB investigated the possibility to detect anomalies on the railway using a trainmounted thermal imaging camera. Rails are also detected in order to determine if an anomaly is on the rail or not. However, the rail detection method does not work satisfactory at long range. The purpose of this master’s thesis is to improve the previous rail detector at long range by using machine learning, and in particular deep learning and a convolutional neural network. Of interest is also to investigate if there are any advantages using cross-modal transfer learning. A labelled dataset for training and testing was produced manually. Also, a loss function tailored to the particular problem at hand was constructed. The loss function was used both for improving the system during training and evaluate the system’s performance during testing. Finally, eight different approaches were evaluated, each one resulting in a different rail detector. Several of the rail detectors, and in particular all the rail detectors using crossmodal transfer learning, perform better than the previous rail detector. Thus, the new rail detectors show great potential to the rail detection problem.
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Luo, Yun Mei. "Modélisation thermo-visco-hyperélastique du comportement du PET dans les conditions de vitesse et de température du procédé de soufflage." Thesis, Paris Est, 2012. http://www.theses.fr/2012PEST1146/document.
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Le soufflage des bouteilles en polyéthylène téréphtalate (PET) génère des modifications importantes des propriétés mécaniques du matériau comme le montre l'étude de caractérisation des propriétés hétérogènes et anisotropes réalisée sur le fond pétaloïde, une partie 3D de géométrie complexe de bouteille soufflée présentée en fin de mémoire. L'étude principale présentée dans ce rapport s'inscrit dans le cadre du procédé de soufflage par bi-orientation où le matériau, qui se trouve à des températures légèrement supérieures à la température de transition vitreuse (Tg), est fortement biétiré générant ainsi de grandes modifications de morphologie microstructurale. Pour permettre à terme une simulation numérique du procédé qui prenne en compte ces modifications de propriétés en cours de soufflage, l'objectif de la thèse est de décrire le comportement du PET par un modèle visco hyperélastique original en grandes déformations, d'identifier ce modèle couplé à la thermique à partir des données expérimentales très récentes de tension biaxiale à des conditions de vitesse et de température proches du procédé et enfin d'implanter ce modèle pour la simulation du procédé. En parallèle, les aspects thermiques, qui s'avèrent fondamentaux pour le procédé, sont explorés via une identification des propriétés thermiques réalisée sur la base d'essais de chauffage infrarouge et de mesure de champs par caméra thermique. La proximité de Tg rend les propriétés mécaniques très sensibles aux moindres variations de température aussi est-il particulièrement important de prédire correctement les conditions thermique initiales de la préforme avant soufflage. De plus, la très forte viscosité à ces températures génère une dissipation importante et qui contribue à l'auto échauffement du matériau modifiant les propriétés mécaniques au cours du temps. La formulation de ce problème thermo-mécanique couplé est implémenté et résolu par la méthode des éléments finis pour simuler le gonflage des préformesThe stretch blow moulding process for polyethylene terephthalate (PET) bottles generates important modifications of the mechanical properties of the material as it can be shown in an identification study of the orthotropic and heterogeneous elastic properties in the 3D region of the petaloïd bottom of PET bottles. The main topic of this work deals with the modelling of the complex behaviour of the PET during the process that is managed at a temperature slightly above the glass transition temperature Tg. In this range of temperature and considering the high strain rates involved during the process, large changes in the material morphology can be observed and the goal of this work is to propose a visco hyperelastic model to predict the PET behaviour under these severe conditions: large deformations, high strain rate… An original procedure is proposed to manage the identification of the material properties from the experimental data of recent biaxial elongation tests. On the other hand, effects of temperature are of fundamental importance during the injection stretch blow moulding process of PET bottles. Near Tg small variations of temperature have great influence on physical properties: an accurate prediction of the initial temperature field generated by the infrared heating is proposed. Also, the important viscous dissipation induces self-heating of the material during the process which is necessary to be taken into account during the numerical simulation. The identification of the thermal parameters is achieved by an experimental infrared heating study. The global thermo mechanical model is implemented and numerical simulations are managed using the finite element method to solve the free blowing of PET preforms
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Hamrell, Hanna. "Image-to-Image Translation for Improvement of Synthetic Thermal Infrared Training Data Using Generative Adversarial Networks." Thesis, Linköpings universitet, Datorseende, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-174928.
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Training data is an essential ingredient within supervised learning, yet time con-suming, expensive and for some applications impossible to retrieve. Thus it isof interest to use synthetic training data. However, the domain shift of syntheticdata makes it challenging to obtain good results when used as training data fordeep learning models. It is therefore of interest to refine synthetic data, e.g. using image-to-image translation, to improve results. The aim of this work is to compare different methods to do image-to-image translation of synthetic training data of thermal IR-images using GANs. Translation is done both using synthetic thermal IR-images alone, as well as including pixelwise depth and/or semantic information. To evaluate, a new measure based on the Frechét Inception Distance, adapted to work for thermal IR-images is proposed. The results show that the model trained using IR-images alone translates the generated images closest to the domain of authentic thermal IR-images. The training where IR-images are complemented by corresponding pixelwise depth data performs second best. However, given more training time, inclusion of depth data has the potential to outperform training withirdata alone. This gives a valuable insight on how to best translate images from the domain of synthetic IR-images to that of authentic IR-images, which is vital for quick and low cost generation of training data for deep learning models.
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Joubert, Pierre. "Thermal and colour data fusion for people detection and tracking." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86453.
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Thesis (MSc)--Stellenbosch University, 2014.ENGLISH ABSTRACT: In this thesiswe approach the problem of tracking multiple people individually in a video sequence. Automatic object detection and tracking is non-trivial as humans have complex and mostly unpredictable movements, and there are sensor noise and measurement uncertainties present. We consider traditional object detection methods and decide to use thermal data for the detection step. This choice is supported by the robustness of thermal data compared to colour data in unfavourable lighting conditions and in surveillance applications. A drawback of using thermal data is that we lose colour information, since the sensor interprets the heat emission of the body rather than visible light. We incorporate a colour sensor which is used to build features for each detected object. These features are used to help determine correspondences in detected objects over time. A problem with traditional blob detection algorithms, which typically consist of background subtraction followed by connected-component labelling, is that objects can appear to split or merge, or disappear in a few frames. We decide to add ‘dummy’ blobs in an effort to counteract these problems. We refrain from making any hard decisions with respect to the blob correspondences over time, and rather let the system decide which correspondences are more probable. Furthermore, we find that the traditional Markovian approach of determining correspondences between detected blobs in the current time step and only the previous time step can lead to unwanted behaviour. We rather consider a sequence of time steps and optimize the tracking across them. We build a composite correspondence model and weigh each correspondence according to similarity (correlation) in object features. All possible tracks are determined through this model and a likelihood is calculated for each. Using the best scoring tracks we then label all the detections and use this labelling as measurement input for a tracking filter. We find that the window tracking approach shows promise even though the data we us for testing is of poor quality and noisy. The system struggles with cluttered scenes and when a lot of dummy nodes are present. Nonetheless our findings act as a proof of concept and we discuss a few future improvements that can be considered.
AFRIKAANSE OPSOMMING: In hierdie tesis benader ons die probleemomverskeiemense individueel in ’n video-opname op te spoor en te volg. Outomatiese voorwerp-opsporing en -volging is nie-triviaal, want mense het komplekse en meestal onvoorspelbare bewegings, en daar is sensor-ruis en metingonsekerhede teenwoordig. Ons neem tradisionele voorwerp-opsporing metodes in ag en besluit om termiese data te gebruik vir die opsporingstap. Hierdie keuse word ondersteun deur die robuustheid van termiese data in vergelyking met kleur data in ongunstige lig-kondisies en in sekuriteitstoepassings. Die nadeel van die gebruik van termiese data is dat ons kleur inligting verloor, aangesien die sensor die hitte vrystelling van die liggaam interpreteer, eerder as sigbare lig. Ons inkorporeer ’n kleur-sensor wat gebruik word om die kenmerke van elke gevolgde voorwerp te bou. Hierdie kenmerke word gebruik om te help om ooreenkomste tussen opgespoorde voorwerpe te bepaal met die verloop van tyd. ’n Probleem met die tradisionele voorwerp-opsporing algoritmes, wat tipies bestaan uit agtergrond- aftrekking gevolg deur komponent-etikettering, is dat dit kan voorkom asof voorwerpe verdeel of saamsmelt, of verdwyn in ’n paar rame. Ons besluit om ‘flous’-voorwerpe by te voeg in ’n poging om hierdie probleme teen te werk. Ons weerhou om enige konkrete besluite oor opgespoorde voorwerpe se ooreenkomste met die verloop van tyd te maak, en laat die stelsel eerder toe om te besluit watter ooreenkomste meer waarskynlik is. Verder vind ons dat die tradisionele Markoviaanse benadering vir die bepaling van ooreenkomste tussen opgespoorde voorwerpe in die huidige tydstap en die vorige een kan lei tot ongewenste gedrag. Ons oorweeg eerder ’n reeks van tydstappe, of ’n venster, en optimeer die volg van voorwerpe oor hulle. Ons bou ’n saamgestelde ooreenstemmingsmodel en weeg elke ooreenstemming volgens die ooreenkoms (korrelasie) tussen voorwerpe se kenmerke. Alle moontlike spore word deur hierdie model bepaal en ’n waarskynlikheid word bereken vir elkeen. Die spore met die beste tellings word gebruik om al die opsporings te nommeer, en hierdie etikettering word gebruik as meting-inset vir ’n volgingsfilter. Ons vind dat die venster-volg benadering belowend vaar selfs al is die invoerdata in ons toetse van swak gehalte en ruiserig. Die stelsel sukkel met besige tonele en wanneer baie flous-voorwerpe teenwoordig is. Tog dien ons bevindinge as ’n bewys van konsep en ons bespreek ’n paar verbeterings wat in die toekoms oorweeg kan word.
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Berthe, Julien. "Comportement thermo-visco-élastique des composites CMO - De la statique à la dynamique grande vitesse." Phd thesis, Ecole Centrale de Lille, 2013. http://tel.archives-ouvertes.fr/tel-00934876.
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Les matériaux composites à matrice organique sont de plus en plus utilisés par l'industrie des transports pour la réalisation d'éléments structuraux. Afin de permettre un dimensionnement optimal de ces structures, il est nécessaire d'améliorer la compréhension et la modélisation du comportement de ces matériaux sur une large gamme de vitesses de sollicitation et de températures d'environnement. Pour cela, plusieurs campagnes expérimentales ont été réalisées sur le T700GC/M21, un composite stratifié à matrice organique, dans le cadre de ces travaux. Tout d'abord, des essais dynamiques sur un vérin hydraulique, ainsi que des essais de fluage, ont été menés afin de caractériser la dépendance à la vitesse du comportement de ce matériau. Ensuite, la dépendance à la température a été mise en évidence à l'aide d'essais à basse température sur vérin hydraulique, complétés d'essais DMA.Les résultats de ces essais ont été utilisés afin de justifier physiquement le développement d'un modèle visco-élastique bi-spectral pour la description de la dépendance à la vitesse du T700GC/M21 sur une large gamme de vitesses de déformation. L'influence de la température d'environnement sur le comportement a quant à elle été introduite à l'aide d'une loi d'Arrhénius. Ce modèle thermo-visco-élastique permet finalement de rendre compte du comportement du stratifié T700GC/M21 sur une large gamme de vitesses et de températures
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Starr, Joseph Wesley. "Rangefinding in Fire Smoke Environments." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/73780.
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The field of robotics has advanced to the point where robots are being developed for use in fire environments to perform firefighting tasks. These environments contain varying levels of fire and smoke, both of which obstruct robotic perception sensors. In order to effectively use robots in fire environments, the issue of perception in the presence of smoke and fire needs to be addressed. The goal of this research was to address the problem of perception, specifically rangefinding, in fire smoke environments.
A series of tests were performed in fire smoke filled environments to evaluate the performance of different commercial rangefinders and cameras as well as a long-wavelength infrared (LWIR) stereo vision system developed in this research. The smoke was varied from dense, low temperature smoke to light, high temperature smoke for evaluation in a range of conditions. Through small-scale experiments on eleven different sensors, radar and LWIR cameras outperformed other perception sensors within both smoke environments. A LWIR stereo vision system was developed for rangefinding and compared to radar, LIDAR, and visual stereo vision in large-scale testing, demonstrating the ability of LWIR stereo vision to rangefind in dense smoke when LIDAR and visual stereo vision fail.
LWIR stereo vision was further developed for improved rangefinding in fire environments. Intensity misalignment between cameras and stereo image filtering were addressed quantitatively. Tests were performed with approximately isothermal scenes and thermally diverse scenes to select subsystem methods. In addition, the effects of image filtering on feature distortion were assessed. Rangefinding improvements were quantified with comparisons to ground truth data.
Improved perception in varying levels of clear and smoke conditions was developed through sensor fusion of LWIR stereo vision and a spinning LIDAR. The data were fused in a multi-resolution 3D voxel domain using evidential theory to model occupied and free space states. A heuristic method was presented to separate significantly attenuated LIDAR returns from low-attenuation returns. Sensor models were developed for both return types and LWIR stereo vision. The fusion system was tested in a range of conditions to demonstrate its ability for improved performance over individual sensor use in fire environments.Ph. D.
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OLARD, François. "Relations entre la composition, la structure et les propriétés thermo-mécaniques des matériaux bitumineux." Habilitation à diriger des recherches, Université Claude Bernard - Lyon I, 2013. http://tel.archives-ouvertes.fr/tel-00851525.
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Le mémoire d'Habilitation à Diriger les Recherches (HDR) de François OLARD présente les principaux travaux de recherche et de diffusion scientifique, depuis sa thèse (2000-2003) jusqu'à aujourd'hui. Comme l'indique en partie le titre du mémoire - " Relations entre la composition, la structure et les propriétés thermo-mécaniques des matériaux bitumineux " -, le fil conducteur de ses travaux de recherche est l'optimisation des performances des matériaux bitumineux par une meilleure compréhension des relations entre leur composition, leur structure et leurs propriétés thermo-mécaniques. Une particularité des travaux de recherche de François OLARD tient à son statut de responsable de projets R&D en entreprise, impliquant la mise en adéquation du savoir et du besoin industriel. Le mémoire d'Habilitation à Diriger les Recherches met ainsi en exergue que nombre d'innovations ont pu naître de l'échange entre recherches appliquée et fondamentale, participant ainsi à l'évolution indispensable du savoir-faire en formulation et en production des matériaux bitumineux. Six thématiques majeures ont été abordées au cours des travaux de recherche: 1) Comportement thermo-mécanique des enrobés bitumineux à basses températures. Relation entre les propriétés du liant et de l'enrobé. 2) Influence des propriétés élastiques ou viscoélastiques des revêtements sur le comportement des ponts à dalle orthotrope (Projet ANR ORTHOPLUS). 3) Formulation d'enrobés bitumineux à hautes performances grâce à l'optimisation de l'empilement granulaire et l'emploi de bitumes modifiés en polymères. 4) Propriétés viscoélastiques linéaires et en fatigue des enrobés bitumineux contenant des agrégats d'enrobés recyclés. 5) Comportement des matériaux composites traités au liant hydraulique et des bétons compactés routiers incluant des fraisâts bitumineux et des fibres métalliques (Projet ANR RECYROUTE). 6) Procédés d'enrobage à basses émissions et à température réduite: enrobés dits " semi-tièdes ". Les thématiques 2 à 4 sont très liées et découlent pour partie du travail initial réalisé en thèse (thématique 1). Ainsi, les approches expérimentales et de modélisation des matériaux bitumineux, testés dans le domaine linéaire principalement, y sont très proches. La thématique 5 présente quant à elle une démarche expérimentale et d'analyse similaire, mais appliquée à deux familles de matériaux composites (graves et bétons) traitées au liant hydraulique et incluant des fraisâts bitumineux. La présence de ces fraisâts bitumineux confère en effet un comportement visco-élastique aux mélanges testés. La thématique 6 présente enfin les recherches liées à l'invention des enrobés à basses émissions et à température réduite, les enrobés bitumineux dits " semi-tièdes ", avec une évaluation des caractéristiques mécaniques et environnementales. La supervision de 23 stages étudiants (Ingénieurs et Mastères) et de 4 doctorants (Génie Civil) a rendu possible une bonne partie de ces travaux et résultats. L'ensemble du travail de recherche a donné lieu à 2 chapitres d'ouvrages scientifiques, 23 publications au sein de revues internationales à comité de lecture, 3 publications au sein de revues françaises à comité de lecture, 54 publications et présentations en conférences internationales, 30 publications de vulgarisation dans la littérature technique & professionnelle, ainsi que 3 brevets internationaux.
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Pegoraro, Paul. "Modélisation analytique de matériaux et de structures composites pour un comportement hygro-thermo-élastique." Paris 6, 1993. http://www.theses.fr/1993PA066737.
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Ramalingam, Nagarajan. "Non-contact multispectral and thermal sensing techniques for detecting leaf surface wetness." Connect to this title online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1104392582.
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Thesis (Ph. D.)--Ohio State University, 2005.Title from first page of PDF file. Document formatted into pages; contains xxii, 271 p.; also includes graphics (some col.) Includes bibliographical references (p. 206-214).
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Luo, Yun Mei, and Yun Mei Luo. "Modélisation thermo-visco-hyperélastique du comportement du PET dans les conditions de vitesse et de température du procédé de soufflage." Phd thesis, Université Paris-Est, 2012. http://tel.archives-ouvertes.fr/tel-00807799.
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Le soufflage des bouteilles en polyéthylène téréphtalate (PET) génère des modifications importantes des propriétés mécaniques du matériau comme le montre l'étude de caractérisation des propriétés hétérogènes et anisotropes réalisée sur le fond pétaloïde, une partie 3D de géométrie complexe de bouteille soufflée présentée en fin de mémoire. L'étude principale présentée dans ce rapport s'inscrit dans le cadre du procédé de soufflage par bi-orientation où le matériau, qui se trouve à des températures légèrement supérieures à la température de transition vitreuse (Tg), est fortement biétiré générant ainsi de grandes modifications de morphologie microstructurale. Pour permettre à terme une simulation numérique du procédé qui prenne en compte ces modifications de propriétés en cours de soufflage, l'objectif de la thèse est de décrire le comportement du PET par un modèle visco hyperélastique original en grandes déformations, d'identifier ce modèle couplé à la thermique à partir des données expérimentales très récentes de tension biaxiale à des conditions de vitesse et de température proches du procédé et enfin d'implanter ce modèle pour la simulation du procédé. En parallèle, les aspects thermiques, qui s'avèrent fondamentaux pour le procédé, sont explorés via une identification des propriétés thermiques réalisée sur la base d'essais de chauffage infrarouge et de mesure de champs par caméra thermique. La proximité de Tg rend les propriétés mécaniques très sensibles aux moindres variations de température aussi est-il particulièrement important de prédire correctement les conditions thermique initiales de la préforme avant soufflage. De plus, la très forte viscosité à ces températures génère une dissipation importante et qui contribue à l'auto échauffement du matériau modifiant les propriétés mécaniques au cours du temps. La formulation de ce problème thermo-mécanique couplé est implémenté et résolu par la méthode des éléments finis pour simuler le gonflage des préformes
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Burns, Joyce Nicole. "Development of a quantitative assay to distinguish glaucoma-causing and benign olfactomedin variants." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/42931.
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Myocilin, expressed in the trabecular meshwork of the eye, has been linked to inherited primary open-angle glaucoma (POAG). The biological function of myocilin is unknown, but mutant myocilin exhibits a gain-of-function mechanism, aggregating within the endoplasmic reticulum of human trabecular meshwork cells, causing cell stress and eventually apoptosis. After apoptosis occurs, the trabecular meshwork is compromised, leading to an increase in intraocular pressure, a symptom of glaucoma. In this thesis, I have expressed and purified the wild-type olfactomedin (OLF) domain and 24 reported disease-causing variants. I developed a facile thermal stability assay using differential scanning fluorimetry, which follows the unfolding of a protein through the fluorescence of a dye sensitive to hydrophobic regions of a protein. Also in this thesis I have determined melting temperatures for the wild-type and for each of the disease-causing mutants. I have tested the stability of the mutants in the presence of seven osmolytes, with sarcosine and trimethylamine-N-oxide restoring the melting temperature closest to wild-type. Additionally, I expressed and purified three reported single nucleotide polymorphisms (SNPs) (E352Q, E396D, K398R), which are considered benign variants. Variants were also compared by circular dichroism, revealing high b-sheet content and wild-type structure. When compared to previous studies, there is a positive correlation between the melting temperature, and previously reported qualitative assays, which measure the mutant myocilin solubility in detergent, secretion from mammalian cells, and aggregation propensity. Taken together, these data give insight into the relationship between glaucoma genotypes and phenotypes.
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Boukamel, Adnane. "Modélisation mécaniques et numériques des matériaux et structures en élastomères." Habilitation à diriger des recherches, Université de la Méditerranée - Aix-Marseille II, 2006. http://tel.archives-ouvertes.fr/tel-00517997.
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Les travaux de recherche, menés depuis une quinzaine d'années, portent sur les développements de modèles mécaniques et numériques permettant de décrire le comportement local et global de pièces complexes constituées d'élastomères. Parmi les développements accomplis durant ces dernières années, citons les plus significatifs: -Modélisation numérique du comportement hyperélastique incompressible et réalisation d'une bibliothèque d'éléments finis. - Mise en oeuvre et validation d'une technique de réduction de modèles à travers la mise à profit des symétries géométriques pour la résolution des problèmes linéaires ou non-linéaires (Eléments finis pseudo-axisymétriques, Eléménts de réduction 3D/2D...) - Modélisation du couplage thermo-viscoélastique en grandes transformations des structures élastomères. - Elaboration de modèles hyper-visco-plastiques, microphysiquement motivés, dans le cadre de la thermodynamique des processus irréversibles. - Développement d'algorithmes d'identification de paramètres des modèles et établissement d'une méthodologie de caractérisation pour les comportements à différentes températures et sous sollicitations dynamiques multifréquences.
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Brüch, André Reinert. "Simulação numérica tridimensional de processos de deformação em bacias sedimentares." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/143898.
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O desenvolvimento de modelos teóricos e computacionais para simular a história de deformação e reconstruir o estado termoporomecânico de bacias sedimentares é de grande interesse da indústria do petróleo. A compactação dos sedimentos, o escoamento dos fluidos e o fluxo térmico são processos de grande importância que ocorrem ao longo da diagênese. Fenômenos puramente mecânicos prevalecem nas camadas superiores da bacia associados à expulsão do fluido e ao rearranjo das partículas sólidas, enquanto a compactação químico-mecânica resultante dos processos de pressão-solução intergranular é dominante nas camadas mais profundas, onde as tensões e temperaturas são maiores. Estes processos de deformação podem ser significativamente afetados pela sua evolução térmica, já que o calor altera a viscosidade dos fluidos e as propriedades físico-químicas dos minerais. O objetivo deste trabalho é desenvolver um modelo constitutivo para o material poroso saturado no contexto da termoporomecânica finita e uma ferramenta computacional com uma interface de multiprocessamento em memória compartilhada baseada no método dos elementos finitos para representar os processos de formação e compactação gravitacional de uma bacia sedimentar. As deformações mecânicas e químico-mecânicas são representadas pela plasticidade e viscoplasticidade, respectivamente. Uma característica fundamental do modelo está relacionada à mudança das propriedades do material poroso em função da variação de temperatura e da evolução de caráter irreversível da sua microestrutura. Simulações numéricas realizadas em condições oedométricas permitem investigar a evolução do modelo constitutivo e do comportamento global da bacia, onde é possível verificar o caráter interdependente dos diferentes processos termoporomecânicos envolvidos. A capacidade da ferramenta computacional de representar problemas tridimensionais complexos é demonstrada a partir de uma história de deposição sedimentar associada a camadas estratigráficas com espessuras variáveis.Development of theoretical and numerical models to simulate the deformation history and rebuild the thermoporomechanical state of sedimentary basins is of great interest for the oil industry. Compaction of sediments, fluid and thermal flows are fundamental coupled processes during diagenesis. Purely mechanical phenomena prevail in the upper layers involving pore fluid expulsion and rearrangement of solid particles, while chemo-mechanical compaction resulting from Intergranular Pressure-Solution (IPS) dominates for deeper burial as stress and temperature increase. The thermal evolution of the basin may substantially affect both processes as heat modifies the viscosity of fluids and physicochemical properties of minerals. The aim of the present contribution is to provide a constitutive model for saturated porous media in the context of finite thermoporomechanics and a numerical tool with a shared memory multiprocessing interface based on the finite element method to deal with depositional phase and gravitational compaction modeling of sedimentary basins. Purely mechanical and chemo-mechanical deformations are respectively modeled by means of plasticity and viscoplasticity. A key feature of the model is related to the evolution of the sediment material properties associated with temperature and large irreversible porosity changes. The evolution of the constitutive model and the overall behavior of the basin are provided by numerical simulations performed under oedometric conditions. The coupled nature of the thermoporomechanical processes is investigated. A depositional history with varying stratigraphic layers is proposed to demonstrate the ability of the numerical tool to model complex 3D problems.
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Bharadwaj, Akshay S. "A Perception Payload for Small-UAS Navigation in Structured Environments." Ohio University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1533649419108963.
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Zeman, Martin. "Pracoviště termovize." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219060.
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This thesis contains an overview of physical principles concerning thermography and infra-red sensing, and a specification of a measuring instrument in a measurement system. Next, there are some particular examples of IR sensing applications. In the second part there is a thermal camera market research including individual manufacturers and models with their attributes and prices. There is a closer view of the thermal camera used for this thesis (Guide EasIR-4). In the end of the thesis there are some drafts of computer vision subject tasks (or practices), including workplace designs and solutions, and three task suggestions for bachelor or diploma theses including solution verifications.
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Stigson, Magnus. "Object Tracking Using Tracking-Learning-Detection inThermal Infrared Video." Thesis, Linköpings universitet, Datorseende, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-93936.
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Automatic tracking of an object of interest in a video sequence is a task that has been much researched. Difficulties include varying scale of the object, rotation and object appearance changing over time, thus leading to tracking failures. Different tracking methods, such as short-term tracking often fail if the object steps out of the camera’s field of view, or changes shape rapidly. Also, small inaccuracies in the tracking method can accumulate over time, which can lead to tracking drift. Long-term tracking is also problematic, partly due to updating and degradation of the object model, leading to incorrectly classified and tracked objects. This master’s thesis implements a long-term tracking framework called Tracking-Learning-Detection which can learn and adapt, using so called P/N-learning, to changing object appearance over time, thus making it more robust to tracking failures. The framework consists of three parts; a tracking module which follows the object from frame to frame, a learning module that learns new appearances of the object, and a detection module which can detect learned appearances of the object and correct the tracking module if necessary. This tracking framework is evaluated on thermal infrared videos and the results are compared to the results obtained from videos captured within the visible spectrum. Several important differences between visual and thermal infrared tracking are presented, and the effect these have on the tracking performance is evaluated. In conclusion, the results are analyzed to evaluate which differences matter the most and how they affect tracking, and a number of different ways to improve the tracking are proposed.
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Su, Shaopu. "Modélisation des bandes de cisaillement adiabatique par une approche énergétique variationnelle." Phd thesis, Ecole centrale de nantes - ECN, 2012. http://tel.archives-ouvertes.fr/tel-00797178.
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Une Bande de Cisaillement Adiabatique (BCA) est une bande étroite associée à de grandes déformations et de hautes températures dans les matériaux ductiles. Il est bien établi que les BCAs impliquent souvent une dépendance au maillage dans la simulation numérique du phénomène localisé. Pour contourner cette difficulté, des modèles de discontinuités ont été proposés et largement appliqués en ingénierie. Cependant, des conditions cruciales doivent être vérifiées afin de développer ces modèles, telles que des descriptions précises des profils physiques, des relations de comportement dans des approches multi-physiques et surtout une capacité de prédiction de la largeur de bande. Sans discrétisation du domaine physique, on propose un nouveau modèle de la structure de BCA basé sur une approche énergétique variationnelle, incluant l'élasticité, l'écrouissage, la conduction de chaleur et la condition limite thermique. Les lois de comportement sont transformées en un problème d'optimisation mathématique par rapport à un ensemble de scalaires. A l'aide d'expressions canoniques de profils de déplacement et de température, la largeur de bande et la température centrale sont calculées en tant que des variables internes du potentiel incrémental total en régime stationnaire et transitoire. Comme application de notre modélisation variationnelle 1D à la localisation de cisaillement, on étend et propose une modélisation variationnelle à deux échelles en introduisant un "élément de localisation de la déformation". Contrairement aux travaux existant, des déformations plastiques et des températures non homogènes sont prises en compte par les expressions analytiques canoniques, et l'évolution de la largeur de bande est calculée comme un problème d'optimisation d'une fonctionnelle énergétique. Une dérivation variationnelle valide sa faisabilité théorique. De même, une implémentation d'élément fini est également dérivée et donne une bonne fondation pour une future mise en oeuvre.
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Lienemann, Matthew A. "Automated Multi-Modal Search and Rescue using Boosted Histogram of Oriented Gradients." DigitalCommons@CalPoly, 2015. https://digitalcommons.calpoly.edu/theses/1507.
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Unmanned Aerial Vehicles (UAVs) provides a platform for many automated tasks and with an ever increasing advances in computing, these tasks can be more complex. The use of UAVs is expanded in this thesis with the goal of Search and Rescue (SAR), where a UAV can assist fast responders to search for a lost person and relay possible search areas back to SAR teams. To identify a person from an aerial perspective, low-level Histogram of Oriented Gradients (HOG) feature descriptors are used over a segmented region, provided from thermal data, to increase classification speed. This thesis also introduces a dataset to support a Bird’s-Eye-View (BEV) perspective and tests the viability of low level HOG feature descriptors on this dataset. The low-level feature descriptors are known as Boosted Histogram of Oriented Gradients (BHOG) features, which discretizes gradients over varying sized cells and blocks that are trained with a Cascaded Gentle AdaBoost Classifier using our compiled BEV dataset. The classification is supported by multiple sensing modes with color and thermal videos to increase classification speed. The thermal video is segmented to indicate any Region of Interest (ROI) that are mapped to the color video where classification occurs. The ROI decreases classification time needed for the aerial platform by eliminating a per-frame sliding window. Testing reveals that with the use of only color data iv and a classifier trained for a profile of a person, there is an average recall of 78%, while the thermal detection results with an average recall of 76%. However, there is a speed up of 2 with a video of 240x320 resolution. The BEV testing reveals that higher resolutions are favored with a recall rate of 71% using BHOG features, and 92% using Haar-Features. In the lower resolution BEV testing, the recall rates are 42% and 55%, for BHOG and Haar-Features, respectively.
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Castres, Magali. "Modélisation dynamique avancée des composites à matrice organique (CMO) pour l’étude de la vulnérabilité des structures aéronautiques." Thesis, Ecole centrale de Lille, 2018. http://www.theses.fr/2018ECLI0006/document.
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Les matériaux composites à matrice organique sont largement utilisés dans l'industrie des transports et notamment dans le domaine aéronautique. Pour permettre un dimensionnement optimal des structures, il est nécessaire d'étudier le comportement des matériaux CMO sur une large gamme de vitesses et de températures.L'objectif de cette thèse est de proposer un modèle de comportement et de rupture permettant de prédire la réponse des CMO sur une large gamme de vitesses de sollicitation et de températures. Les recherches se sont intéressées dans un premier temps à la caractérisation de la transition entre les régimes de comportement linéaire et non linéaire du matériau unidirectionnel T700GC/M21 (renforts de fibres de carbone, résine époxy), ainsi qu'à la dépendance de cette transition à la vitesse de sollicitation et à la température. Les travaux se sont ensuite focalisés sur l'étude expérimentale du régime de comportement non linéaire endommageable du T700GC/M21. Enfin, au terme de ces deux étapes, une version améliorée du modèle disponible à l'ONERA pour les composites stratifiés (OPFM) a été proposée, version intégrant un critère de transition linéaire/non linéaire de comportement, et une prise en compte de l'influence de la vitesse de sollicitation et de la température sur la réponse du matériauNowadays, organic matrix composite materials are widely used in the transportation industry, and particularly in the aeronautical industry. To provide an optimal dimensioning of the structures, it is necessary to study the mechanical behavior of OMC on a large range of strain rates and temperatures. The aim of this PhD thesis is to propose a behavior and a rupture model to predict the mechanical response of OMC for a large range of strain rates and temperatures. The research was initially focused on the characterization of the transition between the linear and nonlinear behavior of the material T700GC/M21, a carbon / epoxy unidirectional laminate as well as the strain rate and temperature dependencies of this transition. The work was then focused on the experimental study of the nonlinear damaged behavior of the T700GC/M21. Finally, completing these first two steps, an updated version of the behavior model available at ONERA (OPFM) was proposed which includes the transition between linear and nonlinear behavior and the influence of strain rate and temperature on the mechanical response of the material
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Rudol, Piotr. "Increasing Autonomy of Unmanned Aircraft Systems Through the Use of Imaging Sensors." Licentiate thesis, Linköpings universitet, UASTECH – Teknologier för autonoma obemannade flygande farkoster, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-71295.
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The range of missions performed by Unmanned Aircraft Systems (UAS) has been steadily growing in the past decades thanks to continued development in several disciplines. The goal of increasing the autonomy of UAS's is widening the range of tasks which can be carried out without, or with minimal, external help. This thesis presents methods for increasing specific aspects of autonomy of UAS's operating both in outdoor and indoor environments where cameras are used as the primary sensors. First, a method for fusing color and thermal images for object detection, geolocation and tracking for UAS's operating primarily outdoors is presented. Specifically, a method for building saliency maps where human body locations are marked as points of interest is described. Such maps can be used in emergency situations to increase the situational awareness of first responders or a robotic system itself. Additionally, the same method is applied to the problem of vehicle tracking. A generated stream of geographical locations of tracked vehicles increases situational awareness by allowing for qualitative reasoning about, for example, vehicles overtaking, entering or leaving crossings. Second, two approaches to the UAS indoor localization problem in the absence of GPS-based positioning are presented. Both use cameras as the main sensors and enable autonomous indoor ight and navigation. The first approach takes advantage of cooperation with a ground robot to provide a UAS with its localization information. The second approach uses marker-based visual pose estimation where all computations are done onboard a small-scale aircraft which additionally increases its autonomy by not relying on external computational power.
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Rodrigues, Valéria Cristina. "Distribuição espacial e bem-estar de aves poedeiras em condições de estresse e conforto térmico utilizando Visão Computacional e Inteligência Artificial." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/11/11131/tde-13032007-161048/.
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As pesquisas sobre comportamento animal possuem como objetivo identificar e quantificar sinais de sofrimento a fim de eliminar os problemas obedecendo às normas de bem-estar. As alterações destes comportamentos mostram as necessidades ambientais para sua sobrevivência. Em certos casos, apenas as mudanças comportamentais podem evidenciar uma situação de estresse. Quando há mudanças na temperatura do ambiente, os animais apresentam várias respostas para manter a temperatura do corpo, começando com a conservação máxima de energia como a inatividade. Duas das mais efetivas características do comportamento termorregulatório incluem seleção de ambiente e ajuste de postura. Técnicas de processamento e análise de imagens podem vir a colaborar com a busca de informações contidas em imagens de animais confinados. Métodos invasivos de quantificação de comportamento mostram que há interferência do experimentador nas reações dos animais, comprometendo os resultados da pesquisa. Este trabalho visou obter, através da Visão Computacional, informações quanto à distribuição espacial de aves poedeiras frente a situações de conforto e estresse térmicos. Foram analisadas seqüências de imagens em ambiente MATLAB 7.0 ® de dois grupos de 5 aves (Hy-line W36) com 21 semanas de idade em condições de conforto térmico (T= 26°C ± 2°C e UR= 60% ± 2%) e 5 aves em condições de estresse térmico (T= 35°C ± 2°C e UR= 70% ± 2%) controladas em câmara climática. As aves foram demarcadas com tintas não tóxicas na região dorsal. Através de técnicas de clusterização de cores e localização do centro geométrico das aves, foi possível analisar a freqüência destas nas regiões de ninho, comedouro, bebedouro, área livre e \"bebedouro + comedouro\", e através do uso de redes Neurais Artificiais, foi possível obter padrões de formas do corpo das aves e relacioná-los a alguns comportamentos. A distribuição espacial é um forte indício das necessidades do animal em diferentes condições evidenciando que a freqüência em algumas regiões pode ser um indicativo de desconforto. A técnica de processamento e análise de imagens mostra-se como um método confiável e livre de subjetividade ou influência da fadiga humana no auxilio da classificação da dinâmica dos animais confinados. Trata-se de uma forma eficiente de analisar imagens de forma rápida para se ter conhecimento da dinâmica dos animais confinados ao longo do tempo. A necessidade do animal é demonstrada através de freqüências em determinadas regiões de interesse para seu bem-estar.The animal behavior researches have as objective identify and quantify suffering signals in order to eliminate the problems obeying the welfare norms. The alterations of these behaviors show the ambient necessities for the animals\' survivals. In certain cases, only the abnormal behaviors can evidence a situation of stress. When the environment temperature changes, the animals present some answers to keep the body\'s temperature constant, starting with the maximum conservation of energy as the inactivity. Two of the most effective characteristics of the thermoregulatory behavior includes environment selection and position adjustment. Image processing and analysis techniques can collaborate with the research of information contained in images of confined animals. Invasive methods of quantification of the behavior show that there is interference of the experimenter on the animal reactions compromising the research results. This work aimed to know, through the Computer Vision, information about the laying hens\' spatial distribution at the thermal comfort and stress situations. Image sequences of two groups of 5 birds (hy-line W36) aging 21 weeks in conditions of thermal comfort (T= 26°C ± 2°C and UR= 60% ± 2%) and 5 birds in conditions had been analyzed of stress thermal (T= 35°C ± 2°C and UR= 70% ± 2%) and controlled in climatic chamber. The birds had been demarcated with not toxic inks in the dorsal region. Through colors clusters techniques in MATLAB 7.0 ® and the localization of the geometric center of the birds, it was possible to analyze the frequency of these birds in the nest regions, feed through, water through, free area and \"water through + feed through\", and through of Artificial Neural Network was possible to have standards shapes of bodies birds and to refers to some behaviors. The spatial distribution is an important indicative fort of the animal necessities in different conditions evidencing that the frequency in some regions can be a discomfort indicative. The processing technique and analysis of the images reveals as a trustworthy method and free of subjectivity or of the fatigue human`s influence in support of the dynamics classification of the confined animals. It is about one of the efficient form to analyze the images to have a better understanding of the dynamics of the confined animals` dynamics throughout time. The necessity of the animal is demonstrated through frequencies in determined regions of interest for its welfare condition.
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Sharma, Vinay. "Simultaneous object detection and segmentation using top-down and bottom-up processing." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1196372113.
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Sambuc, Clément. "Refined damped equivalent fluid models for acoustics." Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209144.
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The acoustics of small cavities raises interest of the scientific community since it involves particular damping mechanisms. In fluid dynamics, when a small perturbation is propagating within a Newtonian and heat-conducting fluid bounded by a rigid and isothermal surface, viscous and thermal dissipative mechanisms are generated near the walls. Such effects can have significant impact on the acoustic behaviour of the system.Several types of practical applications can be cited, among which: hearing aids, micro-electro-mechanical systems (transducers, microphones and loud-speakers), absorbing materials made of thin capillary nets or small pores, dissipative silencers, thermo-acoustic heat exchangers, or any kind of device bringing into play small resonant cavities filled with a dissipative fluid (micro-acoustics).
This study focuses on appropriated reductions of the physical equations, in order to enhance the efficiency of the numerical resolution without adversely affecting the accuracy. Moreover, the proposed strategies lead to numerically stable systems as they involve only one scalar partial order differential equation (or equivalent fluid equation). The emphasis is put on the physical aspect of those reductions, their range of applicability, benefits and drawbacks.
Two new reduced models are proposed to estimate the visco-thermal acoustic wave propagation. A first extension deals with waveguide geometries and relax the hypothesis of the fluid at rest. The second original formulation addresses visco-thermal acoustics in 3D arbitrary geometries. This model is based on different considerations coming from existing techniques as well as the estimation of a wall-distance field.
A second part aims at studying the acoustic behaviour of biphasic materials and more specifically poro-elastic materials. This type of acoustic component is widely used in industry because of their good absorbing properties in the medium- and high-frequency
ranges.
A preliminary bibliographic research deals with the derivation of the set of partial order differential equations that account for both fluid/structure interactions and the anisotropy of a given poro-elastic material. It has been shown that transversely orientated capillary materials (for instance catalyst substrates) can be simulated using the proposed reduction technique.
At last, the modelling of the acoustic transmission between two domains separated by perforated or micro-perforated plates or thin plates of poro-elastic materials is discussed. The analogy between the rigid perforated plate models with an equivalent fluid formulation has been presented. As a result, this model has been extended in order to account for flexural effects of the solid part.
Ce travail porte sur l'étude de certains phénomènes d'amortissements intervenant dans l'acoustique des petites cavités. En méchanique des fluides, lorsqu'une petite perturbation se propage au sein d'un fluide newtonien et caloporteur borné par un mur rigide et isotherme, ces mécanismes dissipatifs particuliers se localisent aux abords des parois et jouent un rôle significatif dans certaines situations.
Parmi les exemples d'applications pratiques, il est possible de citer les appareils d'aide auditive, les systèmes microélectromécaniques (transducteurs, microphones et haut-parleurs), les matériaux absorbants constitués de fins réseaux capillaires ou de pores aux dimensions réduites, les systèmes de silencieux, d'échangeurs de chaleur thermo-acoustiques ou tout autre appareil mettant en jeu des cavités résonantes aux dimensions réduites (micro-acoustique).
L'étude proposée ici se focalise sur des stratégies de réduction appropriées des équations physiques, ceci afin d'améliorer l'efficacité du modèle tout en conservant une précision acceptable. Les techniques présentées aboutissent à des systèmes numériquement stables mettant en jeu une seule équation scalaire (ou équation fluide équivalent). Ainsi, l'accent est porté sur l'aspect physique des réductions, leurs domaines d'application, avantages et inconvénients.
Deux modèles originaux sont proposés afin de prédire la propagation acoustique visco-thermique. Une première extension permet d'évaluer la pression acoustique au sein de géométries particulières de type guides d'onde en présence d'un écoulement hydrodynamique. La seconde formulation présentée s'intéresse à l'acoustique dans des domaines 3D arbitraires. Cette méthode se base sur des considérations conjointes de modèles réduits existants ainsi que sur l'estimation d'un champ de distance à la plus proche paroi.
Dans une seconde partie, nous nous proposons d'étudier le comportement acoustique de matériaux biphasique et plus précisément les matériaux poro-élastiques (très utilisés dans l'industrie en raison de leurs caractéristiques absorbantes dans les domaines des moyennes et hautes fréquences).
Une étude bibliographique préliminaire nous a permis d'exprimer l'ensemble des équations aux dérivées
partielles modélisant à la fois les interactions fluide/structure et l'anisotropie générale des matériaux.
Cette réflexion nous a permis d'aboutir à un modèle de matériau isotrope transverse intéressant, combinant le modèle fluide proposé et la formulation acousto-élastique équivalente. Ainsi la modélisation de structures capillaires orientées (comme les matériaux utilisés dans les catalyseurs automobiles) s'en trouve grandement simplifiée.
Enfin, la transmission acoustique intervenant entre deux domaines fluides séparés par une plaque perforée ou micro-perforée ou bien une couche de matériau poreux a été étudiée. L'analogie entre les modèlisations existantes et un modèle générique de fluide équivalent a été mise en évidence. Pour finir, cette formulation a été étendue afin de prendre en compte les effets de flexion de la partie solide.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished
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Benli, Emrah. "OMNI-DIRECTIONAL INFRARED 3D RECONSTRUCTION AND TRACKING OF HUMAN TARGETS." VCU Scholars Compass, 2017. http://scholarscompass.vcu.edu/etd/5036.
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Omni-directional (O-D) infrared (IR) vision is an effective capability for mobile systems in robotics, due to its advantages: illumination invariance, wide field-of-view, ease of identifying heat-emitting objects, and long term tracking without interruption. Unfortunately, O-D IR sensors have low resolution, low frame rates, high cost, sensor noise, and an increase in tracking time. In order to overcome these disadvantages, we propose an autonomous system application in indoor scenarios including 1) Dynamic 3D Reconstruction (D3DR) of the target view in real time images, 2) Human Behavior-based Target Tracking from O-D thermal images, 3) Thermal Multisensor Fusion (TMF), and 4) Visual Perception for Social Cognition from the motion behavior of the human target.
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Khoury, Georges. "Investigation de l'évolution de la microstructure et de la plasticité des joints de brasure SAC sous effets du vieillissement thermomécanique." Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0124.
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Actuellement, les alliages SAC sont largement utilisés en tant que matériaux de brasure. Les joints de brasure SAC présentent une microstructure dynamique et qui évoluent excessivement sous différentes conditions de vieillissement. La caractéristique de visco-plasticité du SAC étant extrêmement sensible de sa microstructure complique l’évaluation et l’estimation de l’espérance de vie des joints.Ce travail s’adresse à l’amélioration des prédictions de la fiabilité des joints de brasure SAC en contribuant à la compréhension de l’évolution de la microstructure et de la caractéristique mécanique de visco-plasticité du SAC. Ce travail consiste à étudier séparément l’évolution de la microstructure et de la plasticité sous effet du vieillissement.L’étude de la microstructure a permis d’acquérir de nouvelles connaissances sur le coarsening sous différentes conditions de vieillissement. Cette étude a aussi permis d’évaluer l’hypothèse de l’accumulation linéaire du dommage sur la base d’une analyse microstructurale et sur la base d’un cycle thermique avec les différentes conditions qu’il présente.L’étude de la plasticité a permis d’évaluer l’effet du vieillissement par cyclage thermique sur la tenue mécanique du SAC. Cette étude a aussi permis d’évaluer l’effet de la non prise en compte de l’évolution de la caractéristique mécanique de plasticité sur l’estimation de l’espérance de vie des joints de brasure en utilisant les simulations par EFNowadays, SAC alloys are widely used as soldering materials. The SAC solder joints have a dynamic microstructure which evolve excessively under different aging conditions. The characteristic of visco-plasticity of the SAC being extremely sensitive to its microstructure complicates the evaluation and the estimation of the life expectancy of the joints.This work is aimed at improving the predictions of SAC solder joints reliability by contributing to expand knowledge on the evolution of the microstructure and the mechanical characteristic of visco-plasticity of SAC. This work consists in studying separately the evolution of microstructure and plasticity under the effect of aging.The study of the microstructure allowed the gain of new knowledge on the coarsening under different aging conditions. This study also allowed the evaluation of the hypothesis of linear damage accumulation on the microstructural analysis basis and on the basis of a thermal cycle with all the different conditions that it presents.The study of plasticity allowed the assessment of the effect of aging by thermal cycling on the mechanical strength of the SAC. This study also allowed the evaluation of the effect of not taking into account the evolution of the mechanical characteristic of plasticity on the estimation of the life expectancy of the solder joints using finite element simulations
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Thang, Nguyen Duc, and 阮德盛. "EASY LIFE - STUDY THE METHOD “VISION IN PRODUCT DESIGN” (VIP) IN THREE EXAMPLES OF CREATIVE DESIGN PRODUCTS: SLEEPING BAG, FAN CHAIR, THERMO MASSAGE SNEAKERS." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/ffp468.
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Lin, Chih-Hsien, and 林志顯. "Thermal Deformation Measurement and Analysis of Spur Gears using Image Vision." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/43yyxy.
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碩士國立虎尾科技大學
機械與電腦輔助工程系碩士班在職專班
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This study invesitgated thermal deformation measurement and analysis of spur gear based on Tauchi method via image vision recognition technique. The measurement analysis utilizes Matlab software to develop a set of image algorithm computing for the geometric characteristics of the spur gear. The control factors of thermal deformation measurement for the spur gear includes heating temperatures, materials, surface treatments, and cooling types and the measurement analysis is used a L9(34) orthogonal array with 3 levels of Taguchi methods. The effect of coefficient of thermal expansion (CTE) at the different extreme temperatures was investigated for finding most suitable processing parameters for addendum circle of the spur gear. Experiment results showed that the material properties are the most influential factor in thermal deformation; thereby the selection of material is the main cause leading to different product quality levels. In regarding to the geometric characteristic measurement of spur gear, image processing technique is utilized to inspect the contour of the spur gear and is based on grayscale, binary threshold, closing, image rotating, image subtraction and image multiplication. The error value of the addendum and dedendum circle, the major and minor axis of ellipse, the pitch point and the diameter of pitch circle, and the radius and area of the spur gear is under ±2%.
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HUANG, CONG-LIN, and 黃琮淋. "Study on UAV Thermal Image Real-Time Tracking Based on Computer Vision Techniques." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/559ztw.
Full textAbstract:
碩士國立高雄應用科技大學
電機工程系博碩士班
106
Because the related technology of DJI UAV develops rapidly and has many advantages, such as friendly price, high portability, simple operation, and easily assembling by users, many domestic and foreign manufacturers invest in UAV developing one after another, which leads UAV to become a very popular industry. But lots of UAV events has been occurred frequently and caused trouble and danger, such as UAVs went into aviation restricted areas and interfered in flights due to people's mistaken operation, collided famous buildings, and intruded military bases. In order to prevent such mistaken UAV events from happening, many kinds of anti-UAV system have been proposed successively for solving such problems. Because UAV has small volume, hard-to-be-detected material, low sensitivity by general radar, and the system has highly building cost with limited performance. This thesis applies computerized visual technology to track the thermal image of UAV in real-time and expects to replace the expensive radar detecting way, and also uses video capture tool to capture the infrared thermal image in real-time, and then conducts image pre-processing. Frame Difference analyzes the dynamic image tracking of the intruding UAV in real-time, calculating the centroid coordinate of the UAV and screen center displacement, transmitting the coordinate and displacement to the two-axis rotation platform, showing the UAV on screen during the tracking process. This study is conducted with DJI Mavic Pro. This system can achieve the dynamic image tracking of the intruding UAV in 100 meters in sunny day, and can achieve the dynamic image tracking of the intruding UAV in 100 meters in cloudy day.
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(7523927), Hyewon Jeon. "THERMAL IMAGE ANALYSIS FOR FAULT DETECTION AND DIAGNOSIS OF PV SYSTEMS." Thesis, 2020.
Find full textAbstract:
This research presents thermal image analysis for Fault Detection and Diagnosis (FDD) of Photovoltaic (PV) Systems. The traditional manual approach of PV inspection is generally more time-consuming, more dangerous, and less accurate than the modern approach of PV inspection using Aerial Thermography (AT). Thermal image analysis conducted in this research will contribute to utilizing thermography and UAVs for PV inspection by providing a more accurate and cost-efficient diagnosis of PV faults. In this research, PV module inspection was achieved through two steps: (i) PV monitoring and (ii) PV Fault Detection and Diagnosis (FDD). In the PV monitoring stage, PV cells were monitored by aerial thermography. In this stage, the thermal data was acquired for the next step. In the PV FDD stage, hot spot phenomenon and the condition of the PV modules were detected and measured. The proposed research will help with the problems of the modern PV inspection and, eventually, contribute to the performance of PV power generation.
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LEE, CHENG-JEN, and 李正仁. "A Study of the Detection for LED with Machine Vision and Infrared Thermal Imaging technologies." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/21340213124002410372.
Full textAbstract:
碩士華梵大學
機電工程學系博碩專班
98
In this study, IR images are acquired with IR CCD camera, and the detection algorithm is proposed to detect the defect of LED. Detection items include the size, shape, and silver ring of chip which can be extracted using binary, moving noise, hole-filling, blob analysis methods. The detecting software is developed to sort for LED samples. From the experiment results, the methodology presented herein effectively detected and classified LED in high accuracy. In the future, the developed methods can be used to detect the quality of LED online, to increase effective and reduce cost.
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Qi, Xuele. "Ultrafast Laser Induced Thermo-Elasto-Visco-Plastodynamics in Single Crystalline Silicon." 2009. http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7393.
Full textAbstract:
A comprehensive model for describing the fundamental mechanism dictating the
interaction of ultrafast laser pulse with single crystalline silicon wafer is formulated.
The need for establishing the feasibility of employing lasers of subpicosecond pulse
width in Laser Induced Stress Waves Thermometry (LISWT) for single crystalline
silicon processing motivated the work. The model formulation developed is of a
hyperbolic type capable of characterizing non-thermal melting and thermo-elastoviscoplastic
deformation as functions of laser input parameters and ambient temperature.
A plastic constitutive law is followed to describe the complex elasto-viscoplastic
responses in silicon undergoing Rapid Thermal Processing (RTP) annealing at elevated
temperatures. A system of nine first-order hyperbolic equations applicable to describing
3-D elasto-viscoplastic wave motions in silicon is developed. The group velocities of
certain selected frequency components are shown to be viable thermal indicators, thus
establishing the feasibility of exploiting nanosecond laser induced propagating stress
waves for the high-resolution thermal profiling of silicon wafers.
Femtosecond laser induced transport dynamics in silicon is formulated based on
the relaxation-time approximation of the Boltzmann equation. Temperature-dependent
multi-phonons, free-carrier absorptions, and the recombination and impact ionization
processes governing the laser model and carrier numbers are considered using a set of
balance equations. The balance equation of lattice energy and equations of motion of
both parabolic and hyperbolic types are derived to describe the complex thermo-elastoplastodynamic
behaviors of the material in response to ultrafast laser pulsing. The
solution strategy implemented includes a multi-time scale axisymmetric model of finite
geometry and a staggered-grid finite difference scheme that allows both velocity and
stress be simultaneously determined without having to solve for displacements.
Transport phenomena initiated by femtosecond pulses including the spatial and temporal
evolutions of electron and lattice temperatures, along with electron-hole carrier density,
are found to be functions of laser fluence and pulse width. The femtosecond laser
heating model that admits hyperbolic energy transport is shown to remedy the dilemma
that thermal disturbances propagate with infinite speed. Non-thermal melting fluence is
examined favorably against published experimental data. That it is feasible to explore
femtosecond laser induced displacement and stress components for 1K resolution
thermal profiling is one of the conclusions reached.
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"Stagioni: Temperature management to enable near-sensor processing for performance, fidelity, and energy-efficiency of vision and imaging workloads." Master's thesis, 2019. http://hdl.handle.net/2286/R.I.51565.
Full textAbstract:
abstract: Vision processing on traditional architectures is inefficient due to energy-expensive off-chip data movements. Many researchers advocate pushing processing close to the sensor to substantially reduce data movements. However, continuous near-sensor processing raises the sensor temperature, impairing the fidelity of imaging/vision tasks.
The work characterizes the thermal implications of using 3D stacked image sensors with near-sensor vision processing units. The characterization reveals that near-sensor processing reduces system power but degrades image quality. For reasonable image fidelity, the sensor temperature needs to stay below a threshold, situationally determined by application needs. Fortunately, the characterization also identifies opportunities -- unique to the needs of near-sensor processing -- to regulate temperature based on dynamic visual task requirements and rapidly increase capture quality on demand.
Based on the characterization, the work proposes and investigate two thermal management strategies -- stop-capture-go and seasonal migration -- for imaging-aware thermal management. The work present parameters that govern the policy decisions and explore the trade-offs between system power and policy overhead. The work's evaluation shows that the novel dynamic thermal management strategies can unlock the energy-efficiency potential of near-sensor processing with minimal performance impact, without compromising image fidelity.Dissertation/Thesis
Masters Thesis Computer Engineering 2019
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Israel, Martin. "Entwicklung eines UAV-basierten Systems zur Rehkitzsuche und Methoden zur Detektion und Georeferenzierung von Rehkitzen in Thermalbildern: Der Fliegende Wildretter." Doctoral thesis, 2016. https://repositorium.ub.uni-osnabrueck.de/handle/urn:nbn:de:gbv:700-2016120515171.
Full textAbstract:
Die vorliegende Arbeit beschäftigt sich mit der Entwicklung eines UAV-basierten Systems und der zugehörigen Methodenentwicklung zur automatisierten Rehkitzsuche in Feldern. Jedes Jahr sterben sehr viele Wildtiere -- vor allem Rehkitze -- während dem Mähen von landwirtschaftlich genutzten Wiesen. Mit herkömmlichen Methoden ist es unter vertretbarem Aufwand bisher nicht gelungen, die Zahl der Mähopfer auf ein erträgliches Maß zu reduzieren. Mit der Entwicklung des in dieser Arbeit beschriebenen "Fliegenden Wildretters" könnte sich das in Zukunft ändern. Mit Hilfe einer Wärmebildkamera aus der Vogelperspektive lässt sich ein warmes Tier, wie ein Rehkitz, wesentlich leichter aufspüren, als mit herkömmlichen Methoden. Auslegung und Aufbau des Systems orientieren sich speziell an dem Aspekt, wie eine möglichst hohe Flächenleistung erreicht werden kann, ohne dabei Tiere zu übersehen. Drei Faktoren sind besonders wichtig, um dieses Ziel zu erreichen: Eine hohe Geschwindigkeit des gesamten Suchprozesses, eine zuverlässige Detektion und eine präzise Lokalisierung der Tiere. Durch Automatisierung lassen sich viele Teilaspekte dieser Aufgabe beschleunigen. Deshalb werden im Rahmen dieser Arbeit verschiedene Methoden entwickelt und validiert, unter anderem zur Flugplanung, Flugsteuerung, Bilddaten-Auswertung, Objekt-Detektion und Georeferenzierung.
Die Kenntnis der Rehkitz-Merkmale und der Einflussgrößen bei der Thermalbilderfassung helfen, die Qualität der Detektion zu erhöhen, weshalb sie in dieser Arbeit besondere Berücksichtigung finden.
Auch die Präzision der Lokalisierung lässt sich durch Kenntnis der Einflussgrößen auf die Positions- und Lagemessung des UAVs erhöhen. Anhand von umfangreichen Messkampagnen wird die Funktion und Qualität des Systems unter realen Bedingungen belegt.
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Bouery, Charbel. "Contribution au développement de stratégies algorithmiques pour la résolution de problèmes thermo-mécaniques couplés par une approche énergétique variationnelle." Phd thesis, 2012. http://tel.archives-ouvertes.fr/tel-00827159.
Full textAbstract:
Les sources de couplage thermomécanique dans les matériaux viscoélastiques sont multiples : thermo-élasticité, dissipation visqueuse, évolution des caractéristiques mécaniques avec la température. La simulation numérique de ces couplages en calcul des structures présente encore un certain nombre de défis, spécialement lorsque les effets de couplage sont très marqués (couplage fort). De nombreuses approches algorithmiques ont été proposées dans la littérature pour ce type de problème. Ces méthodes vont des approches monolithiques, traitant simultanément l'équilibre mécanique et l'équilibre thermique, aux approches étagées, traitant alternativement chacun des sous-problèmes mécanique et thermique. La difficulté est d'obtenir un bon compromis entre les aspects de précision, stabilité numérique et coût de calcul. Récemment, une approche variationnelle des problèmes couplés a été proposée par Yang et al. (2006), qui permet d'écrire les équations d'équilibre mécanique et thermique sous la forme d'un problème d'optimisation d'une fonctionnelle scalaire. Cette approche variationnelle présente notamment les avantages de conduire à une formulation numérique à structure symétrique, et de permettre l'utilisation d'algorithmes d'optimisation. Dans ce travail on utilise l'approche variationnelle pour résoudre le problème thermo-visco-élastique fortement couplé, puis on compare plusieurs schémas algorithmiques afin de trouver celui qui présente les meilleures performances.
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Gago, Nuno Alexandre Silva Fernandes do. "Fusão multissensorial para aplicação em robô de monitorização agrícola." Master's thesis, 2018. http://hdl.handle.net/1822/57431.
Full textAbstract:
Dissertação de mestrado em Engenharia Eletrónica Industrial e ComputadoresOs recentes avanços em múltiplas áreas de sensorização (deteção de proximidade, múltiplos formatos de sistemas de visão e posicionamento por satélite) têm vindo a aumentar a utilização dos veículos terrestres não tripulados na Indústria Agrícola. Estes veículos, suportando a análise contínua, dinâmica e de proximidade, permitem a potencial otimização da produção alimentar e/ou controlo de infestações. Esta dissertação apresenta o desenvolvimento de um veículo terrestre não tripulado, enquadrado na área da robótica de serviços, para uso em Agricultura de precisão. O veículo terrestre não tripulado integra uma Plataforma Móvel, Grupo Ótico e Plataforma de Computação. Relativamente à Plataforma Móvel, toda a estrutura foi fabricada com a perspetiva de poder ser reproduzida de forma livre, open source, utilizando metodologias de fabrico por impressão 3D. Esta prototipagem foi complementada por peças produzidas em fresagem e torneamento CNC, utilizando técnicas modernas de assemblagem. Para o Grupo Ótico, seguiu-se a mesma filosofia de open source, com uso de impressão 3D, complementada com a seleção de equipamentos de aquisição de imagem numa gama de baixo orçamento. Foram documentados todos os passos suportando o desenvolvimento de um sensor de visão térmica de baixo custo e grupos de câmaras multiespectrais, com posterior validação e calibração em testes padronizados. Na Plataforma de Computação foi utilizada uma placa comercial, Nvidia Jetson®, com desenvolvimento de software (meta-sistema operativo ROS), facilitando a recolha do avultado volume de dados fornecidos por todos os sensores. Por fim, a Plataforma Móvel, Grupo Ótico e Plataforma de Computação foram integradas numa plataforma única, veículo terrestre não tripulado, com o intuito de aplicabilidade e facilitação de aquisição de dados em sistemas reais da indústria de Agricultura de precisão, bem como potencial extrapolação às áreas de Segurança Civil e Militar.
The recent advances in multiple areas of sensorization (proximity sensing, multiple vision system formats and satellite positioning) have been increasing the use of unmanned ground vehicles in the Agricultural Industry. These vehicles, supporting the continuous, dynamic and proximity analysis, allow the potential optimization of food production and / or control of infestations. This dissertation presents the development of an unmanned ground vehicle, framed in the area of service robotics, for use in precision agriculture. The unmanned ground vehicle integrates a Mobile Platform, Optical Group and a Computing Platform. Regarding the Mobile Platform, the entire structure was manufactured with the perspective of being able to be freely reproduced, open source, using manufacturing methodologies for 3D printing. These prototypes were complemented by parts produced in CNC milling and turning, using modern assembly techniques. For the Optical Group, the same philosophy of open source was followed, using 3D printing, complemented by the selection of image acquisition equipment in a low budget range. We documented all the steps supporting the development of a low-cost thermal vision sensor and multispectral chamber groups, with subsequent calibration and validation in standardized tests. In the computing platform, a commercial card, Nvidia Jetson®, was developed with software development (ROS operating meta-system), making it easy to collect the large amount of data provided by all the sensors. Finally, the mobile platform, Optical Group and computing platform were integrated into a single platform in an unmanned ground vehicle, with the purpose of applying and facilitating the acquisition of data in real systems of the precision agriculture industry, as well as potential extrapolation to the areas of Civil Security and Military.