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Gracia, Álvaro de. "Thermal analysis of a ventilated facade with phase change materials (PCM)." Doctoral thesis, Universitat de Lleida, 2013. http://hdl.handle.net/10803/117144.
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L’objectiu d’aquesta tesis és el de analitzar el comportament tèrmic d’una façana ventilada amb material de canvi de fase macro encapsulat en el seu canal d’aire. L’ús de materials de canvi de fase incrementa la capacitat d’emmagatzematge d’energia tèrmica en la solució constructiva proposada, i intensifica l’emmagatzematge i l’operació de la façana ventilada a un rang de temperatures desitjat.
El rendiment energètic d’aquest nou tipus de façana ventilada s’estudia de forma experimental per veure el seu potencial en reduir els consums energètics tant de calefacció com de refrigeració. Posteriorment, s’estudia mitjançant l’anàlisi de cicle de vida, quin és l’impacte mediambiental que suposa la manufactura i operació d’aquest sistema. Finalment, es desenvolupa un model numèric per optimitzar el funcionament i disseny d’aquesta façana. Aquest model numèric utilitza una nova correlació empírica de nombre de Nusselt, per al càlcul dels coeficients de transferència de calor entre el material de canvi de fase i el flux d’aire circulant per la cambra.El objetivo de esta tesis es el de analizar el comportamiento térmico de una fachada ventilada con material de cambio de fase macro encapsulado en su canal de aire. El uso de materiales de cambio de fase aumenta la capacidad de almacenamiento de energía térmica en la solución constructiva propuesta, e intensifica el almacenamiento y la operación de la fachada ventilada a un rango de temperaturas deseado. El rendimiento energético de este nuevo tipo de fachada ventilada se estudia experimentalmente para ver su potencial en reducir los consumos energéticos tanto de calefacción como de refrigeración. Posteriormente, se estudia mediante el análisis de ciclo de vida, el impacto medioambiental que supone la manufactura y operación de este sistema. Finalmente, se desarrolla un modelo numérico que optimiza el funcionamiento y diseño de esta fachada. Este modelo numérico utiliza una nueva correlación empírica de número de Nusselt, para el cálculo de los coeficientes de transferencia de calor entre el material de cambio de fase y el flujo de aire circulando por la cámara.
The objective of this thesis is to analyse the thermal behaviour of a ventilated façade with macro-encapsulated phase change material in its air channel. The use of phase change materials increases the ability of thermal energy storage in the proposed constructive system, and enhances the storage and operation of the ventilated facade to a desired temperature range. The energy efficiency of this new type of ventilated facade is experimentally studied to determine its potential in reducing the energy consumption both for heating and cooling. Hereafter, the environmental impact of the manufacture and operation of this system is studied by a life cycle analysis. Finally, a numerical model is developed to optimize the operation and design of this facade. This numerical model uses a new empirical correlation for the Nusselt number to calculate the convective heat transfer coefficients between the phase change material and the air flow circulating in the chamber.
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Scharf, Alexander. "Terrestrial Laser Scanning for Wooden Facade-system Inspection." Thesis, Luleå tekniska universitet, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-77159.
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The objective of this study was to evaluate the feasibility of measuring movement, deformation and displacement in wooden façade-systems by terrestrial laser scanning. An overview of different surveying techniques and methods has been created. Point cloud structure and processing was explained in detail as it is the foundation for understanding the advantages and disadvantages of laser scanning. The boundaries of monitoring façades with simple and complex façade structures were tested with the phase-based laser scanner FARO Focus 3DS. In-field measurements of existing facades were done to show the capabilities of extracting defect features such as cracks by laser scanning. The high noise in the data caused by the limited precision of 3D laser scanners is problematic. Details on a scale of several mm are hidden by the data noise. Methods to reduce the noise during point cloud processing have proven to be very data-specific. The uneven point cloud structure of a façade scan made it therefore difficult to find a method working for the whole scans. Dividing the point cloud data automatically into different façade parts by a process called segmentation could make it possible. However, no suitable segmentation algorithm was found and developing an own algorithm would have exceeded the scope of this thesis. Therefore, the goal of automatic point cloud processing was not fulfilled and neglected in the further analyses of outdoor facades and laboratory experiments. The experimental scans showed that several information could be extracted out of the scans. The accuracy of measured board and gap dimensions were, however, highly depended on the point cloud cleaning steps but provided information which could be used for tracking development of a facade’s features. Extensive calibration might improve the accuracy of the measurements. Deviation of façade structures from flat planes were clearly visible when using colorization of point clouds and might be the main benefit of measuring spatial information of facades by non-contact methods. The determination of façade displacement was done under laboratory conditions. A façade panel was displaced manually, and displacement was calculated with different algorithms. The algorithm determining distance to the closest point in a pair of point clouds provided the best results, while being the simplest one in terms of computational complexity. Out-of-plane displacement was the most suitable to detect with this method. Displacement sideways or upwards required more advanced point cloud processing and manual interpretation by the software operator. Based on the findings during the study it can be concluded that laser scanning is not the correct methods for structural health monitoring of facades when the tracking of small deformations, especially deformations below 5 mm and defects like cracks are the main goal. Displacements, defects and deformations of larger scale can be detected but are tied to a large amount of point cloud processing. It is not clear if the equipment costs, surveying time and the problems caused by high variability of scans results based on façade color, shape and texture are in a positive relation to the benefits obtained from using laser scanning over manually surveying.
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Altahlawi, Naif Tarik. "Integrated Thermal and Daylight Performance Comparison of Single and Double Glass Skin Facade for Hot Climate Conditions." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/90783.
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Visual integration of the building interior and exterior is one of the charms of today's architecture. The Double-Skin facade system is a technology that can reduce the drawbacks of using glass in a building's elevation. In fact, the double-skin façade (DSF) offers transparency while reducing energy consumption when compared to single-skin systems in cold and moderate weather conditions. However, there is no clear evidence of how the system will perform in hot climate conditions. In this research, a testing procedure was established to experimentally evaluate the performance of the double-skin façade system, data was collected to create multiple regression models, and then evaluate the double-skin façade's performance and compare it to a single-skin system in hot arid climate conditions.Doctor of Philosophy
Improving the quality of indoor environments is a main goal in today’s architecture. Towards this goal, the use of glass and curtain walls is common in office buildings. The building façade is a key factor for the amount of energy consumed to reach comfort levels in the building. That is, because facades influence lighting, glare, heat gain, noise safety and energy usage. Therefore, the use of glass improves transparency which can interfere with comfort levels inside the building due to solar heat gain. The Double Skin façade system is widely adopted in Europe and has been shown to reduce energy used for heating in cold weather. In winter, heat losses can be reduced as the system’s intermediate cavity acts as a thermal buffer. However, there is no clear understanding of how the system will perform in hot arid climate conditions where cooling is the dominant operating mode. A Double Skin Façade can provide shading during the overheating period, while having the desired glass elevations sought by designers. This is due to ventilation and solar control devices located inside the system’s cavity. Being placed between the interior and the exterior glass panels, solar control devices are protected from the weather, which in return decreases its size. Furthermore, the additional glass panel allows windows in the system’s inner layer to be opened for natural ventilation. Unfortunately, the performance of the Double Skin Façade system for hot arid climate is not well documented. Therefore, the primary goal of this research is to compare the thermal and light performance of the Double Skin Façade system to a single façade system for hot weather conditions.
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Baker, Nicholas. "Modelling and Analysis of Daylight, Solar Heat Gains and Thermal Losses to Inform the Early Stage of the Architectural Process." Thesis, KTH, Installations- och energisystem, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-222470.
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The EU building sector is a main contributor to greenhouse gas emissions, which need to be cut as part of the global response to anthropogenic climate change. This cut can be realised through improvements in building energy performance, such as optimisation of facade design. The early stage of the architectural process has been identified as the ideal time to implement such sustainable design choices. There is need for simple guidelines and tools to provide quantitative data to support these architectural decisions. BIM and parametric design can provide this, by facilitating model-based analysis and simulation, as part of an unbroken flow of information through the design process. This study uses Dynamo (the visual programming add-in for Autodesk Revit) together with the Honeybee and Ladybug environmental plugins, to conduct daylight, solar heat gains and thermal losses analyses and simulations. The aim was to identify limitations and opportunities in using Dynamo-Revit, to establish an optimal range for glazing-to-wall ratio (GWR) and to provide some simple room-sizing guidelines for architects in the early stage of the design process. The Dynamo-Revit workflow was found to be effective for specific projects, but difficult to perfect for multiple different projects. An optimal range for GWR was found as 30-40% for east, south and west-facing rooms and around 50% for rooms facing only north. Results were tabulated, linking room orientation and depth with estimated daylight access, solar heat gains and thermal losses. The results were reasonable, but could be improved by the use of more sophisticated analysis and simulation techniques, which should be facilitated by forthcoming development of Honeybee and Ladybug in Dynamo.
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Ok, David. "Mise en correspondance robuste et détection de modèles visuels appliquées à l'analyse de façades." Phd thesis, Université Paris-Est, 2013. http://pastel.archives-ouvertes.fr/pastel-00974556.
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Depuis quelques années, avec l'émergence de larges bases d'images comme Google Street View, la capacité à traiter massivement et automatiquement des données, souvent très contaminées par les faux positifs et massivement ambiguës, devient un enjeu stratégique notamment pour la gestion de patrimoine et le diagnostic de l'état de façades de bâtiment. Sur le plan scientifique, ce souci est propre à faire avancer l'état de l'art dans des problèmes fondamentaux de vision par ordinateur. Notamment, nous traitons dans cette thèse les problèmes suivants: la mise en correspondance robuste, algorithmiquement efficace de caractéristiques visuelles et l'analyse d'images de façades par grammaire. L'enjeu est de développer des méthodes qui doivent également être adaptées à des problèmes de grande échelle. Tout d'abord, nous proposons une formalisation mathématique de la cohérence géométrique qui joue un rôle essentiel pour une mise en correspondance robuste de caractéristiques visuelles. A partir de cette formalisation, nous en dérivons un algorithme de mise en correspondance qui est algorithmiquement efficace, précise et robuste aux données fortement contaminées et massivement ambiguës. Expérimentalement, l'algorithme proposé se révèle bien adapté à des problèmes de mise en correspondance d'objets déformés, et à des problèmes de mise en correspondance précise à grande échelle pour la calibration de caméras. En s'appuyant sur notre algorithme de mise en correspondance, nous en dérivons ensuite une méthode de recherche d'éléments répétés, comme les fenêtres. Celle-ci s'avère expérimentalement très efficace et robuste face à des conditions difficiles comme la grande variabilité photométrique des éléments répétés et les occlusions. De plus, elle fait également peu d'hallucinations. Enfin, nous proposons des contributions méthodologiques qui exploitent efficacement les résultats de détections d'éléments répétés pour l'analyse de façades par grammaire, qui devient substantiellement plus précise et robuste
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Ritz, Carolina, and Malin Mattsson-Mårn. "Utformningens betydelse för energiförbrukningen : En fallstudie av verksamhetsbyggnader." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Byggnadsteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-28281.
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Purpose: The building sector accounts for 40 % of the total energy consumption in Sweden today, and the largest proportion is consumed during the operating phase. From the year 2020 and onwards, all new buildings should be erected as zero-emissionbuildings. The building’s design can reduce energy demands, but the current legal requirements do not favour energy-efficient designs. This study focuses on the design’s importance for the energy efficiency of buildings, i.e., energy-saving design. The impact of specific measures is difficult to calculate due to the complexity of reality. This study aims to highlight the measures that could reduce energy consumption in commercial buildings. Method: In order to provide answers to the issues stated in the report and to achieve the objective of the study, case studies are being conducted investigating three commercial buildings where deliberate decisions were made to use energy-reducing measures. Results and conclusions are based on qualitative interviews and literature studies. Findings: The energy-reducing design measures found to be of most importance used in the studied buildings are the form factor, the window portion and the thermal storage capacity. Moreover, significant savings are possible by carefully consider how solar energy can be limited or used in the building. Generally, buildings tends to become more technical, therefore technical knowledge early in the process is important to reach a good result. Economic incentives and clear objectives with right focus are also important for optimizing a building’s energy performance. The wording and the requirement levels in the Swedish building regulations highly controls the construction of energy efficient buildings. Implications: This study shows how energy efficient design is made today and provides an indication of what can be done and what should be prioritized. By imposing requirements on consumed energy instead of bought, energy efficient design could be favoured. Furthermore, this study suggests that a balance between windows, façade and solar shading are important energy-reducing measures. Regardless of selected energyreducing measures, a good performance is essential. Finally, this study shows that a methodical use of existing knowledge and technology makes a difference. Limitations: A lifecycle approach provides an overall picture of a building’s energy consumption. However, this study is based on the energy consumption during the operating phase. The result of this study does not take economic or aesthetic factors into account. This study is a comparative case study and is based on few but carefully matched cases. The selected cases are commercial buildings where deliberate decisions were made to use energy-reducing measures.
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Fojtík, Petr. "Letištní terminál." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-239964.
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My diploma thesis is focused on design and assessment of structural system of airport terminal. The design is processed in two options. Both of them has the same dimensions but structural system is changed. Floor plan is in the shape of part of annulus. Width of the hall is changing, in the middle of the hall is aproximatly 90 m. Length is 52,5 m, 10 m of this length is porch. Roof slope is 3° towards to the front of the hall.
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Hariri, Walid. "Contribution à la reconnaissance/authentification de visages 2D/3D." Thesis, Cergy-Pontoise, 2017. http://www.theses.fr/2017CERG0905/document.
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L’analyse de visages 3D y compris la reconnaissance des visages et des expressions faciales 3D est devenue un domaine actif de recherche ces dernières années. Plusieurs méthodes ont été développées en utilisant des images 2D pour traiter ces problèmes. Cependant, ces méthodes présentent un certain nombre de limitations dépendantes à l’orientation du visage, à l’éclairage, à l’expression faciale, et aux occultations. Récemment, le développement des capteurs d’acquisition 3D a fait que les données 3D deviennent de plus en plus disponibles. Ces données 3D sont relativement invariables à l’illumination et à la pose, mais elles restent sensibles à la variation de l’expression. L’objectif principal de cette thèse est de proposer de nouvelles techniques de reconnaissance/vérification de visages et de reconnaissance d’expressions faciales 3D. Tout d’abord, une méthode de reconnaissance de visages en utilisant des matrices de covariance comme des descripteurs de régions de visages est proposée. Notre méthode comprend les étapes suivantes : le prétraitement et l’alignement de visages, un échantillonnage uniforme est ensuite appliqué sur la surface faciale pour localiser un ensemble de points de caractéristiques. Autours de chaque point, nous extrayons une matrice de covariance comme un descripteur de région du visage. Deux méthodes d’appariement sont ainsi proposées, et différentes distances (géodésiques / non-géodésique) sont appliquées pour comparer les visages. La méthode proposée est évaluée sur troisbases de visages GAVAB, FRGCv2 et BU-3DFE. Une description hiérarchique en utilisant trois niveaux de covariances est ensuite proposée et validée. La deuxième partie de cette thèse porte sur la reconnaissance des expressions faciales 3D. Pour ce faire, nous avons proposé d’utiliser les matrices de covariances avec les méthodes noyau. Dans cette contribution, nous avons appliqué le noyau de Gauss pour transformer les matrices de covariances en espace d’Hilbert. Cela permet d’utiliser les algorithmes qui sont déjà implémentés pour l’espace Euclidean (i.e. SVM) dans cet espace non-linéaire. Des expérimentations sont alors entreprises sur deux bases d’expressions faciales 3D (BU-3DFE et Bosphorus) pour reconnaître les six expressions faciales prototypiques3D face analysis including 3D face recognition and 3D Facial expression recognition has become a very active area of research in recent years. Various methods using 2D image analysis have been presented to tackle these problems. 2D image-based methods are inherently limited by variability in imaging factors such as illumination and pose. The recent development of 3D acquisition sensors has made 3D data more and more available. Such data is relatively invariant to illumination and pose, but it is still sensitive to expression variation. The principal objective of this thesis is to propose efficient methods for 3D face recognition/verification and 3D facial expression recognition. First, a new covariance based method for 3D face recognition is presented. Our method includes the following steps : first 3D facial surface is preprocessed and aligned. A uniform sampling is then applied to localize a set of feature points, around each point, we extract a matrix as local region descriptor. Two matching strategies are then proposed, and various distances (geodesic and non-geodesic) are applied to compare faces. The proposed method is assessed on three datasetsincluding GAVAB, FRGCv2 and BU-3DFE. A hierarchical description using three levels of covariances is then proposed and validated. In the second part of this thesis, we present an efficient approach for 3D facial expression recognition using kernel methods with covariance matrices. In this contribution, we propose to use Gaussian kernel which maps covariance matrices into a high dimensional Hilbert space. This enables to use conventional algorithms developed for Euclidean valued data such as SVM on such non-linear valued data. The proposed method have been assessed on two known datasets including BU-3DFE and Bosphorus datasets to recognize the six prototypical expressions
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Garcia, Robert. "Analyse architecturale informatisee de la face en norma lateralis : application aux protocoles chirurgico-orthodontiques." Paris 7, 1989. http://www.theses.fr/1989PA07GA02.
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Bordei, Cristina. "Face analysis using polynomials." Thesis, Poitiers, 2016. http://www.theses.fr/2016POIT2259/document.
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Considéré comme l'un des sujets de recherche les plus actifs et visibles de la vision par ordinateur, de la reconnaissance des formes et de la biométrie, l'analyse faciale a fait l'objet d'études approfondies au cours des deux dernières décennies. Le travail de cette thèse a pour objectif de proposer de nouvelles techniques d'utilisation de représentations de texture basées polynômes pour l'analyse faciale.La première partie de cette thèse est dédiée à l'intégration de bases de polynômes dans les modèles actifs d'apparence. Nous proposons premièrement une manière d'utiliser les coefficients polynomiaux dans la modélisation de l'apparence. Ensuite, afin de réduire la complexité du modèle nous proposons de choisir et d'utiliser les meilleurs coefficients en tant que représentation de texture. Enfin, nous montrons comment ces derniers peuvent être utilisés dans un algorithme de descente de gradient.La deuxième partie de la thèse porte sur l'utilisation des bases polynomiales pour la détection des points/zones d'intérêt et comme descripteur pour la reconnaissance des expressions faciales. Inspirés par des techniques de détection des singularités dans des champ de vecteurs, nous commençons par présenter un algorithme utilisé pour l'extraction des points d'intérêt dans une image. Puis nous montrons comment les bases polynomiales peuvent être utilisées pour extraire des informations sur les expressions faciales. Puisque les coefficients polynomiaux fournissent une analyse précise multi-échelles et multi-orientation et traitent le problème de redondance efficacement ils sont utilisés en tant que descripteurs dans un algorithme de classification d'expression facialeAs one of the most active and visible research topic in computer vision, pattern recognition and biometries, facial analysis has been extensively studied in the past two decades. The work in this thesis presents novel techniques to use polynomial basis texture representations for facial analysis. The first part of this thesis, is dedicated to the integration of polynomial bases in the Active Appearance Models - a set of statistical tools that proved to be very efficient in modeling faces. First we propose a way to use the coefficients obtained after polynomial projections in the appearance modeling. Then, in order to reduce model complexity we proposed to select and use as a texture representation the strongest polynomial coefficients. Finally we show how in addition to the texture representation polynomial coefficients can be used in a gradient descent algorithm since polynomial decomposition is equivalent to a filter bank.The second part of the thesis concems the use of the polynomial bases for interesting points and areas detection and as a descriptor for facial expression recognition. We start by presenting an algorithm used for accurate image keypoints localization inspired by techniques of singularities detection in a vector field. Our approach consists in two major steps: the calculation of an image vector field of normals and the keypoint selection within the field both presented in a multi-scale multi resolution scheme. Finally we show how polynomial bases can be used to extract informations about facial expressions. Polynomial coefficients are used as descriptors in an facial expression classification algorithm
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Plante, Jacques. "The problem of designing facades within an industrialized building system : a technical analysis for criticising and evaluating contemporary buildings." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/78792.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1985.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH.
Includes bibliographical references (p. 246-254).
Designing facades is one of the most important and delicate problems in contemporary architecture. The facade is the changing zone par excelience within which the structural elements of technology meld into refined details of art and together constitute Architecture. The facade is also an interface. or link, between two faces 1 and phases: the facade reflects the evolution of the plan for the private interior side. and is also the expression of the plan on the public exterior side. Very strong tensions. defined spatially. temporally, and architecturally are generated and constantly renewed by interior and exterior forces. Resolving these forces architecturally and artistically through building systems design. modern technology. and a vocabulary meaningful to users is tremendously problematic in the evaluation and critic of three case studies. This will be the subject of this thesis. in which the aspect of repetition in facades will be a dominant aspect.
by Jacques Plante.
M.S.
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Altskog, Tomas. "Customized Analytics Software : Investigating efficient development of an application." Thesis, Mittuniversitetet, Avdelningen för informations- och kommunikationssystem, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-27967.
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Google Analytics is the most widely used web traffic analytics program in the world with a wide array of functionality which serve several different purposes for its users. However the cost of training employees in the usage of Google Analytics can be expensive and time consuming due to the generality of the software. The purpose of this thesis is to explore an alternative solution to hav- ing employees learn the default Google Analytics interface and thus possibly re- ducing training expenses. A prototype written in the Java programming lan- guage is developed which implements the MVC and facade software patterns for the purpose of making the development process more efficient. It contains a feature for retrieving custom reports from Google Analytics using Google’s Core Reporting API in addition to two web pages are integrated into the proto- type using the Google Embed API. In the result the prototype is used along with the software estimation method COCOMO to make an estimation of the amount of effort required to develop a similar program. This is done by counting the prototype’s source lines of code manually, following the guidelines given by the COCOMO manual, and then implementing the result in the COCOMO estima- tion formula. The count of lines of code for the entire prototype is 567 and the count which considers reused code is 466. The value retrieved from the formula is 1.61±0.14 person months for the estimation of the entire program and 1.31± 0.16 for a program with reused code. The conclusion of the thesis is that the res- ult from the estimation has several weaknesses and further research is necessary in order to improve the accuracy of the result.
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Kafetzi, Evi. "L'Ethos dans l'Argumentation : le cas du face à face Sarkozy / Royal 2007." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0053/document.
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En quête d'efficacité et d'influence, tout candidat aux électionsprésidentielles tente de se fabriquer et de donner à voir une image de soi conformeaux attentes des électeurs concernant le profil d'un futur chef d'État. Cette imagede soi séduisante construite à travers le discours, appelée ethos en rhétorique, faitpartie intégrante de l'argumentation au même titre que ses autres composantes, àsavoir le logos et le pathos. Le discours politique, en tant que porteur d'importantsenjeux, est le terrain de construction identitaire par excellence.Ce travail explore les stratégies communicatives dans l'activitéargumentative qu'est le débat politique télévisé. Les données sont constituées parle face à face télévisé du 2 mai 2007 entre Nicolas Sarkozy et Ségolène Royal, àla veille du deuxième tour des élections présidentielles françaises.Je me propose dans ce travail de dégager les règles et les mécanismes surlesquels repose la fabrication d'une image de soi télévisuelle par les praticiens dela persuasion que sont les hommes et les femmes politiques, afin de parvenir àleurs fins. Les outils langagiers dont les deux adversaires se servent lors du dueltélévisé en question ici, pour nous servir une image de soi conforme au modèleprésidentiel « idéal » sont analysés un par un. Ainsi, ayant une meilleureconnaissance des coulisses de la rhétorique audiovisuelle, l'électeur-téléspectateurdevient maître de sa décision et responsable de son choix, et apprend à se méfierdes sentiments et des impressions que lui inspirent les praticiens de la persuasionIn search of effectiveness and influence, every candidate who stands forpresidential elections attempts to create and give to the audience a self-imageconsistent with the elector's expectations concerning a future head of state'sprofile. This attractive self-image created through discourse, called ethos inrhetoric, is an integral part of argumentation, as well as its other components,logos and pathos. Political discourse, as a vector of important stakes, constitutesthe ground of identity construction par excellence.This work explores communication strategies in argumentation activity,and particularly in televised political debate. The data is constituted by thetelevised face to face of the 2nd of May 2007 between Nicolas Sarkozy andSégolène Royal, at the eve of the second ballot of the French presidentialelection.What I propose in this work is to draw up the rules and mechanisms thatgovern the making of one's televised self-image by politicians, spin doctors, inorder to achieve their ends. I propose to analyse, one by one, the linguistic toolsthat the two opponents use in order to give the audience a self-image consistentwith an ideal presidential model, during the televised duel that we're studyinghere. In this way, having a better knowledge of what goes on behind the scenesof audiovisual rhetoric, the elector-televiewer becomes master of his decisionand has the control of his choice and learns to beware of feelings andimpressions inspired by the professionals of persuasion
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Al-Dahoud, Ahmad. "The computational face for facial emotion analysis: Computer based emotion analysis from the face." Thesis, University of Bradford, 2018. http://hdl.handle.net/10454/17384.
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Facial expressions are considered to be the most revealing way of understanding the human psychological state during face-to-face communication. It is believed that a more natural interaction between humans and machines can be undertaken through the detailed understanding of the different facial expressions which imitate the manner by which humans communicate with each other.
In this research, we study the different aspects of facial emotion detection, analysis and investigate possible hidden identity clues within the facial expressions. We study a deeper aspect of facial expressions whereby we try to identify gender and human identity - which can be considered as a form of emotional biometric - using only the dynamic characteristics of the smile expressions. Further, we present a statistical model for analysing the relationship between facial features and Duchenne (real) and non-Duchenne (posed) smiles. Thus, we identify that the expressions in the eyes contain discriminating features between Duchenne and non-Duchenne smiles.
Our results indicate that facial expressions can be identified through facial movement analysis models where we get an accuracy rate of 86% for classifying the six universal facial expressions and 94% for classifying the common 18 facial action units. Further, we successfully identify the gender using only the dynamic characteristics of the smile expression whereby we obtain an 86% classification rate. Likewise, we present a framework to study the possibility of using the smile as a biometric whereby we show that the human smile is unique and stable.Al-Zaytoonah University
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Buchala, Samarasena. "Computational analysis of face images." Thesis, University of Hertfordshire, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431938.
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Amin, Syed Hassan. "Analysis of 3D face reconstruction." Thesis, Imperial College London, 2009. http://hdl.handle.net/10044/1/6163.
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This thesis investigates the long standing problem of 3D reconstruction from a single 2D face image. Face reconstruction from a single 2D face image is an ill posed problem involving estimation of the intrinsic and the extrinsic camera parameters, light parameters, shape parameters and the texture parameters. The proposed approach has many potential applications in the law enforcement, surveillance, medicine, computer games and the entertainment industries. This problem is addressed using an analysis by synthesis framework by reconstructing a 3D face model from identity photographs. The identity photographs are a widely used medium for face identi cation and can be found on identity cards and passports. The novel contribution of this thesis is a new technique for creating 3D face models from a single 2D face image. The proposed method uses the improved dense 3D correspondence obtained using rigid and non-rigid registration techniques. The existing reconstruction methods use the optical ow method for establishing 3D correspondence. The resulting 3D face database is used to create a statistical shape model. The existing reconstruction algorithms recover shape by optimizing over all the parameters simultaneously. The proposed algorithm simplifies the reconstruction problem by using a step wise approach thus reducing the dimension of the parameter space and simplifying the opti- mization problem. In the alignment step, a generic 3D face is aligned with the given 2D face image by using anatomical landmarks. The texture is then warped onto the 3D model by using the spatial alignment obtained previously. The 3D shape is then recovered by optimizing over the shape parameters while matching a texture mapped model to the target image. There are a number of advantages of this approach. Firstly, it simpli es the optimization requirements and makes the optimization more robust. Second, there is no need to accurately recover the illumination parameters. Thirdly, there is no need for recovering the texture parameters by using a texture synthesis approach. Fourthly, quantitative analysis is used for improving the quality of reconstruction by improving the cost function. Previous methods use qualitative methods such as visual analysis, and face recognition rates for evaluating reconstruction accuracy. The improvement in the performance of the cost function occurs as a result of improvement in the feature space comprising the landmark and intensity features. Previously, the feature space has not been evaluated with respect to reconstruction accuracy thus leading to inaccurate assumptions about its behaviour. The proposed approach simpli es the reconstruction problem by using only identity images, rather than placing eff ort on overcoming the pose, illumination and expression (PIE) variations. This makes sense, as frontal face images under standard illumination conditions are widely available and could be utilized for accurate reconstruction. The reconstructed 3D models with texture can then be used for overcoming the PIE variations.
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Ruiz, Hernandez John Alexander. "Analyse faciale avec dérivées Gaussiennes." Thesis, Grenoble, 2011. http://www.theses.fr/2011GRENM039/document.
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Dans cette thèse, nous explorons l'utilisation des dérivées Gaussiennes multi-échelles comme représentation initiale pour la détection, la reconnaissance et la classification des visages humains dans des images. Nous montrons qu'un algorithme rapide, $O(N)$, de construction d'une pyramide binomiale peut être utilisé pour extraire des dérivées Gaussiennes avec une réponse impulsionnelle identique à un facteur d'échelle $sqrt{2}$>. Nous montrons ensuite qu'un vecteur composé de ces dérivées à différentes échelles et à différents ordres en chaque pixel peut être utilisé comme base pour les algorithmes de détection, de classification et de reconnaissance lesquels atteignent ou dépassent les performances de l'état de l'art avec un coût de calcul réduit. De plus l'utilisation de coefficients entiers, avec une complexité de calcul et des exigences mémoires en $O(N)$ font qu'une telle approche est appropriée pour des applications temps réel embarquées sur des systèmes mobiles. Nous testons cette représentation en utilisant trois problèmes classiques d'analyse d'images faciales : détection de visages, reconnaissance de visages et estimation de l'âge. Pour la détection de visages, nous examinons les dérivées Gaussiennes multi-échelles comme une alternative aux ondelettes de Haar pour une utilisation dans la construction d'une cascade de classifieurs linéaires appris avec l'algorithme Adaboost, popularisé par Viola and Jones. Nous montrons que la représentation pyramidale peut être utilisée pour optimiser le processus de détection en adaptant la position des dérivées dans la cascade. Dans ces experiences nous sommes capables de montrer que nous pouvons obtenir des niveaux de performances de détection similaires (mesurés par des courbes ROC) avec une réduction importante du coût de calcul. Pour la reconnaissance de visages et l'estimation de l'âge, nous montrons que les dérivées Gaussiennes multi-échelles peuvent être utilisées pour calculer une représentation tensorielle qui conserve l'information faciale la plus importante. Nous montrons que combinée à l'Analyse Multilinéaire en Composantes Principales et à la méthode Kernel Discriminative Common Vectors (KDCV), cette représentation tensorielle peut mener à un algorithme qui est similaire aux techniques concurrentes pour la reconnaissance de visages avec un coût de calcul réduit. Pour l'estimation de l'âge à partir d'images faciales, nous montrons que notre représentation tensorielle utilisant les dérivées de Gaussiennes multi-échelles peut être utilisée avec une machine à vecteur de pertinence pour fournir une estimation de l'âge avec des niveaux de performances similaires aux méthodes de l'état de l'artIn this thesis, we propose to modelize facial images using Gaussian Derivatives computed with a Half-Octave Gaussian Pyramid. In this scope, Gaussian derivatives have shown a high versatility in object recognition and image analysis, nevertheless there is not a considerable number of proposed aproaches in the state-of-the-art that uses Gaussian derivatives for extracting important information from facial images. Motivated by the above mentioned and the high amount of applications in facial analysis, security systems and Biometry, in this thesis as a first time, we propose to use an unique image representation, the Gaussian Scale Space computed with a half octave pyramid. We show in this thesis that this image representation could be used to perform different tasks in facial analysis without lost of performance compared with other approaches in the state-of-the-art that uses more complicated image representations. it is also well know that using an unique image represenation could be convenient in real world applications where the amount of memory capacity is limitated by hardware constraints. To demostrate our assumptations we solve three different tasks in facial analysis: Face detection, Face recognition and Age estimation. In face detection we propose to use a cascade of classifiers using Gaussian derivatives. Specifically we propose to use Gaussian derivatives up to the fourth order, in effect experiemnts using different derivatives orders have shown that fourth order Gaussian derivatives provide important information in face detection and recognition. In adition, to improve the speed of detection using Gaussian derivatives, we develope a new cascade architecture which considerates the computational cost of each Gaussian derivative order to chose its best position in the cascade. Finally, to solve the face recognition and age estimation problems, we propose a tensorial model based in Gaussian derivatives. This tensorial model preserves the 3-D structure of feature space and it does not break the natural structure of data when a vectorization process is applied. Each one of the methods proposed in the thesis are discused and validated with a set of well defined experiments. All our results are compared with the last state-of-the-art results in face detection, recognition and age estimation, giving comparable or superior results
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Mahmood, Muhammad Tariq. "Face Detection by Image Discriminating." Thesis, Blekinge Tekniska Högskola, Avdelningen för för interaktion och systemdesign, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4352.
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Human face recognition systems have gained a considerable attention during last few years. There are very many applications with respect to security, sensitivity and secrecy. Face detection is the most important and first step of recognition system. Human face is non rigid and has very many variations regarding image conditions, size, resolution, poses and rotation. Its accurate and robust detection has been a challenge for the researcher. A number of methods and techniques are proposed but due to a huge number of variations no one technique is much successful for all kinds of faces and images. Some methods are exhibiting good results in certain conditions and others are good with different kinds of images. Image discriminating techniques are widely used for pattern and image analysis. Common discriminating methods are discussed.SIPL, Mechatronics, GIST 1 Oryong-Dong, Buk-Gu, Gwangju, 500-712 South Korea tel. 0082-62-970-2997
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Wei, Xiaozhou. "3D facial expression modeling and analysis with topographic information." Diss., Online access via UMI:, 2008.
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Patrick, William Charles. "Investigation, Analysis, and Modeling of Longwall Face-to-Face Transfers." Diss., This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06092008-112841/.
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Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1993.Vita. Abstract. Attached pocket for diagrams. Includes bibliographical references (leaves 155-162). Also available via the Internet.
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Zhao, Shuyan. "Face analysis under near infrared illumination." Göttingen Cuvillier, 2008. http://d-nb.info/990811492/04.
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Alfonso, Miñambres Javier de. "Face recognition using principal component analysis." Master's thesis, Universidade de Aveiro, 2010. http://hdl.handle.net/10773/10221.
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Mestrado em Engenharia Electrónica e TelecomunicaçõesThe purpose of this dissertation was to analyze the image processing method known as Principal Component Analysis (PCA) and its performance when applied to face recognition. This algorithm spans a subspace (called facespace) where the faces in a database are represented with a reduced number of features (called feature vectors). The study focused on performing various exhaustive tests to analyze in what conditions it is best to apply PCA. First, a facespace was spanned using the images of all the people in the database. We obtained then a new representation of each image by projecting them onto this facespace. We measured the distance between the projected test image with the other projections and determined that the closest test-train couple (k-Nearest Neighbour) was the recognized subject. This first way of applying PCA was tested with the Leave{One{Out test. This test takes an image in the database for test and the rest to build the facespace, and repeats the process until all the images have been used as test image once, adding up the successful recognitions as a result. The second test was to perform an 8{Fold Cross{Validation, which takes ten images as eligible test images (there are 10 persons in the database with eight images each) and uses the rest to build the facespace. All test images are tested for recognition in this fold, and the next fold is carried out, until all eight folds are complete, showing a different set of results. The other way to use PCA we used was to span what we call Single Person Facespaces (SPFs, a group of subspaces, each spanned with images of a single person) and measure subspace distance using the theory of principal angles. Since the database is small, a way to synthesize images from the existing ones was explored as a way to overcoming low successful recognition rates. All of these tests were performed for a series of thresholds (a variable which selected the number of feature vectors the facespaces were built with, i.e. the facespaces' dimension), and for the database after being preprocessed in two different ways in order to reduce statistically redundant information. The results obtained throughout the tests were within what expected from what can be read in literature: success rates of around 85% in some cases. Special mention needs to be made on the great result improvement between SPFs before and after extending the database with synthetic images. The results revealed that using PCA to project the images in the group facespace is very accurate for face recognition, even when having a small number of samples per subject. Comparing personal facespaces is more effective when we can synthesize images or have a natural way of acquiring new images of the subject, like for example using video footage. The tests and results were obtained with a custom software with user interface, designed and programmed by the author of this dissertation.
O propósito desta Dissertação foi a aplicação da Analise em Componentes Principais (PCA, de acordo com as siglas em inglês), em sistemas para reconhecimento de faces. Esta técnica permite calcular um subespaço (chamado facespace, onde as imagens de uma base de dados são representadas por um número reduzido de características (chamadas feature vectors). O estudo realizado centrou-se em vários testes para analisar quais são as condições óptimas para aplicar o PCA. Para começar, gerou-se um faces- pace utilizando todas as imagens da base de dados. Obtivemos uma nova representação de cada imagem, após a projecção neste espaço, e foram medidas as distâncias entre as projecções da imagem de teste e as de treino. A dupla de imagens de teste-treino mais próximas determina o sujeito reconhecido (classificador vizinhos mais próximos). Esta primeira forma de aplicar o PCA, e o respectivo classificador, foi avaliada com as estratégias Leave{One{Out e 8{Fold Cross{Validation. A outra forma de utilizar o PCA foi gerando subespaços individuais (designada por SPF, Single Person Facespace), onde cada subespaço era gerado com imagens de apenas uma pessoa, para a seguir medir a distância entre estes espaços utilizando o conceito de ângulos principais. Como a base de dados era pequena, foi explorada uma forma de sintetizar novas imagens a partir das já existentes. Todos estes teste foram feitos para uma série de limiares (uma variável threshold que determinam o número de feature vectors com os que o faces- pace é construído) e diferentes formas de pre-processamento. Os resultados obtidos estavam dentro do esperado: taxas de acerto aproximadamente iguais a 85% em alguns casos. Pode destacar-se uma grande melhoria na taxa de reconhecimento após a inclusão de imagens sintéticas na base de dados. Os resultados revelaram que o uso do PCA para projectar imagens no subespaço da base de dados _e viável em sistemas de reconhecimento de faces, principalmente se comparar subespaço individuais no caso de base de dados com poucos exemplares em que _e possível sintetizar imagens ou em sistemas com captura de vídeo.
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Liu, Feng. "Face Gear Design and Compliance Analysis." The Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=osu1392373365.
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Hu, Guosheng. "Face analysis using 3D morphable models." Thesis, University of Surrey, 2015. http://epubs.surrey.ac.uk/808011/.
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Face analysis aims to extract valuable information from facial images. One effective approach for face analysis is the analysis by synthesis. Accordingly, a new face image synthesised by inferring semantic knowledge from input images. To perform analysis by synthesis, a genera- tive model, which parameterises the sources of facial variations, is needed. A 3D Morphable Model (3DMM) is commonly used for this purpose. 3DMMs have been widely used for face analysis because the intrinsic properties of 3D faces provide an ideal representation that is immune to intra-personal variations such as pose and illumination. Given a single facial input image, a 3DMM can recover 3D face (shape and texture) and scene properties (pose and illumination) via a fitting process. However, fitting the model to the input image remains a challenging problem. One contribution of this thesis is a novel fitting method: Efficient Stepwise Optimisation (ESO). ESO optimises sequentially all the parameters (pose, shape, light direction, light strength and texture parameters) in separate steps. A perspective camera and Phong reflectance model are used to model the geometric projection and illumination respectively. Linear methods that are adapted to camera and illumination models are proposed. This generates closed-form solu- tions for these parameters, leading to an accurate and efficient fitting. Another contribution is an albedo based 3D morphable model (AB3DMM). One difficulty of 3DMM fitting is to recover the illumination of the 2D image because the proportion of the albedo and shading contributions in a pixel intensity is ambiguous. Unlike traditional methods, the AB3DMM removes the illumination component from the input image using illumination normalisation methods in a preprocessing step. This image can then be used as input to the AB3DMM fitting that does not need to handle the lighting parameters. Thus, the fitting of the AB3DMM becomes easier and more accurate. Based on AB3DMM and ESO, this study proposes a fully automatic face recognition (AFR) system. Unlike the existing 3DMM methods which assume the facial landmarks are known, our AFR automatically detects the landmarks that are used to initialise our fitting algorithms. Our AFR supports two types of feature extraction: holistic and local features. Experimental results show our AFR outperforms state-of-the-art face recognition methods.
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Huang, Jian. "Discriminant analysis algorithms for face recognition." HKBU Institutional Repository, 2006. http://repository.hkbu.edu.hk/etd_ra/655.
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Zhao, Xi. "3D face analysis : landmarking, expression recognition and beyond." Phd thesis, Ecole Centrale de Lyon, 2010. http://tel.archives-ouvertes.fr/tel-00599660.
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This Ph.D thesis work is dedicated to automatic facial analysis in 3D, including facial landmarking and facial expression recognition. Indeed, facial expression plays an important role both in verbal and non verbal communication, and in expressing emotions. Thus, automatic facial expression recognition has various purposes and applications and particularly is at the heart of "intelligent" human-centered human/computer(robot) interfaces. Meanwhile, automatic landmarking provides aprior knowledge on location of face landmarks, which is required by many face analysis methods such as face segmentation and feature extraction used for instance for expression recognition. The purpose of this thesis is thus to elaborate 3D landmarking and facial expression recognition approaches for finally proposing an automatic facial activity (facial expression and action unit) recognition solution.In this work, we have proposed a Bayesian Belief Network (BBN) for recognizing facial activities, such as facial expressions and facial action units. A StatisticalFacial feAture Model (SFAM) has also been designed to first automatically locateface landmarks so that a fully automatic facial expression recognition system can be formed by combining the SFAM and the BBN. The key contributions are the followings. First, we have proposed to build a morphable partial face model, named SFAM, based on Principle Component Analysis. This model allows to learn boththe global variations in face landmark configuration and the local ones in terms of texture and local geometry around each landmark. Various partial face instances can be generated from SFAM by varying model parameters. Secondly, we have developed a landmarking algorithm based on the minimization an objective function describing the correlation between model instances and query faces. Thirdly, we have designed a Bayesian Belief Network with a structure describing the casual relationships among subjects, expressions and facial features. Facial expression oraction units are modelled as the states of the expression node and are recognized by identifying the maximum of beliefs of all states. We have also proposed a novel method for BBN parameter inference using a statistical feature model that can beconsidered as an extension of SFAM. Finally, in order to enrich information usedfor 3D face analysis, and particularly 3D facial expression recognition, we have also elaborated a 3D face feature, named SGAND, to characterize the geometry property of a point on 3D face mesh using its surrounding points.The effectiveness of all these methods has been evaluated on FRGC, BU3DFEand Bosphorus datasets for facial landmarking as well as BU3DFE and Bosphorus datasets for facial activity (expression and action unit) recognition.
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Wang, Jing. "Reconstruction and Analysis of 3D Individualized Facial Expressions." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32588.
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This thesis proposes a new way to analyze facial expressions through 3D scanned faces of real-life people. The expression analysis is based on learning the facial motion vectors that are the differences between a neutral face and a face with an expression. There are several expression analysis based on real-life face database such as 2D image-based Cohn-Kanade AU-Coded Facial Expression Database and Binghamton University 3D Facial Expression Database. To handle large pose variations and increase the general understanding of facial behavior, 2D image-based expression database is not enough. The Binghamton University 3D Facial Expression Database is mainly used for facial expression recognition and it is difficult to compare, resolve, and extend the problems related detailed 3D facial expression analysis. Our work aims to find a new and an intuitively way of visualizing the detailed point by point movements of 3D face model for a facial expression.
In our work, we have created our own 3D facial expression database on a detailed level, which each expression model has been processed to have the same structure to compare differences between different people for a given expression.
The first step is to obtain same structured but individually shaped face models. All the head models are recreated by deforming a generic model to adapt a laser-scanned individualized face shape in both coarse level and fine level. We repeat this recreation method on different human subjects to establish a database. The second step is expression cloning. The motion vectors are obtained by subtracting two head models with/without expression. The extracted facial motion vectors are applied onto a different human subject’s neutral face. Facial expression cloning is proved to be robust and fast as well as easy to use. The last step is about analyzing the facial motion vectors obtained from the second step. First we transferred several human subjects’ expressions on a single human neutral face. Then the analysis is done to compare different expression pairs in two main regions: the whole face surface analysis and facial muscle analysis.
Through our work where smiling has been chosen for the experiment, we find our approach to analysis through face scanning a good way to visualize how differently people move their facial muscles for the same expression. People smile in a similar manner moving their mouths and cheeks in similar orientations, but each person shows her/his own unique way of moving. The difference between individual smiles is the differences of movements they make.
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Lu, Hua. "Video Analysis for Micro- Expression Spotting and Recognition." Thesis, Rennes, INSA, 2018. http://www.theses.fr/2018ISAR0005/document.
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Les principales contributions de cette these, en analyse d'image, portent sur l’etude des caracteristiques de reperage et de reconnaissance des micro-expressions. les approches d’analyse d’expressions faciales dans le domaine de la vision par ordinateur consistent a les detecter et a les classer dans des videos. par rapport a la macro-expression, une micro-expression induit dans une partie du visage un changement rapide durant moins d'une demi-seconde. de plus, cette subtile apparition dans une partie du visage rend difficile sa detection et sa reconnaissance. ces dernieres annees ont connu un interet croissant pour des algorithmes d’extraction automatique de micro-expressions faciales. cela a ete motive par des applications dans des contextes a enjeux eleves tels les enquetes criminelles, les points de controle des aeroports et des transports en commun, le contre-terrorisme, … le choix de caracteristiques faciales efficaces joue un role crucial dans l’analyse des micro-expressions.ce travail se concentre sur la partie d’extraction de caracteristiques, en proposant diverses methodes pour les taches de detection et de reconnaissance de micro-expression.la detection constitue la premiere etape dans l'analyse des micro-expressions. les methodes de detection existantes basees sur des caracteristiques, tels les motifs binaires locaux (lbp), l’histogramme de gradients orientes (hog), le flux optique, souffrent de complexite de mise en œuvre entrainant un probleme d'implementation en temps reel. ainsi, dans cette these, une methode de detection basee sur la projection integrale est proposee pour resoudre ce probleme. cependant, toutes les caracteristiques ci-dessus sont extraites des visages recadres et rognees ; ce qui cause, generalement, un decalage residuel entre les images. pour resoudre ce probleme, est proposee une autre methode de detection basee sur des caracteristiques geometriques. cette derniere exploite les distances geometriques entre des points cles du visage sans necessite de recadrer l'image. ceci permet de capturer des deplacements geometriques subtils le long des sequences et s’avere approprie pour differentes taches d’analyse faciale qui requierent une grande vitesse de calcul.parmi les caracteristiques de reconnaissance de micro-expressions existantes, celles de mouvement basees sur le flux optique presentent des avantages dans la caracterisation de mouvements subtils sur le visage. toutefois, il reste difficile de determiner les emplacements precis de chaque mappage de traits du visage entre les differentes trames par flux optique, meme si les images ont ete alignees. un tel probleme peut donner lieu a une mauvaise estimation, a la fois, de l'orientation et de l’amplitude associees au flux optique. pour y pallier, nous proposons une nouvelle approche (dite fmbh) basee sur les histogrammes de frontiere de mouvement (mbh). elle permet de supprimer les mouvements inattendus causes par un mauvais recalage residuel apparaissant entre les images recadrees tout en capturant le mouvement relatif caracterisant la micro-expression. cette caracteristique est generee en combinant les composantes horizontales et verticales du differentiel de flux optique.les differents developpements de ce travail ont conduit a des etudes comparatives avec des approches de l'etat de l'art sur des bases de donnees bien connues et exploitees par la communaute du domaine. les resultats experimentaux, ainsi obtenues, montrent l'efficacite de nos contributionsRecent years, there has been an increasing interest in the computer vision in automatic facial micro-expression algorithms. this has been driven by applications in high-stakes contexts such as criminal investigations, airport and mass transit checkpoints, counter terrorism, and so on. micro-expression approaches in computer vision area consist of detecting and classifying them from videos. compared to macro-expression, a micro-expression involves a rapid change which lasts less than a half of second, and moreover, its subtle appearance in part of the face makes detection and recognition difficult to achieve. effective facial features play a crucial role for micro-expression analysis. this thesis focuses on the feature extraction parts, by developing various feature extraction methods for types of micro-expression detection and recognition tasks.the detection of micro-expressions is the first step for its analysis. this thesis aims to spot micro-expressions from videos. existing detection methods based on features, such as the local binary patterns, the histogram of gradient, the optical flow suffer difficulties in computation consuming leading to real-time implementation problem. thus, in this thesis, the spotting method based on integral projection to address this problem. however, all the above features are extracted from cropped faces which usually cause residual mis-registration that appears between images. in order to deal with this issue, another detection method based on geometrical feature is proposed. it involves the geometrical distances between facial key-points without the need of cropping face. this captures subtle geometric displacements along sequences and is proved to be suitable for different facial analysis tasks that require high computational speed. for micro-expression recognition, motion features based on the optical flow have advantages in characterizing subtle movements on face among the existing recognition features. it is still a difficult problem for optical flow to determine the accurate locations of each facial feature mappings between different images even though the face images have been aligned. such an issue may give rise to wrong orientation and magnitude estimation associated to the optical flow field. in order to address this problem, the motion boundary histograms are considered. it can remove unexpected motions caused by residual mis-registration that appears between images cropped from different frames. nevertheless, the relative motion can be captured. based on the the motion boundary, a new descriptor the fusion motion boundary histograms is introduced. this feature is generated by combing both the horizontal and the vertical components of the differential of optical flow as inspired from the motion boundary histograms. the main contributions of this thesis lie at the study of features for micro-expressions spotting and recognition. experiments on the micro-expression databases show the effectiveness of the presented contributions
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Abecassis, Empis Cecilia. "Analysis of the compartment fire parameters influencing the heat flux incident on the structural façade." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4188.
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In recent years several high-profile building fires have highlighted shortcomings in the way we design for the complex interaction of structures and fire. These weaknesses appear to arise from a combination of gaps in knowledge of some of the more intricate aspects of compartment fire dynamics and from limitations in the engineering applications developed to date from hitherto established fundamentals. In particular the One Meridian Plaza Fire (1991), the Madrid Windsor Tower Fire (2005) and the Lakanal House Fire (2009) have emphasised the need for further study in the field of post-flashover compartment fires and the often consequent external fires that emerge from the compartment openings. External fire plumes impinge upon the structural façade, causing added structural stress, and often result in external fire spread and secondary ignition in upper level compartments. Hence a better understanding of the effect had by the internal compartment fire on the development of external flaming and the insult of the plume to its surroundings is beneficial for Structural Engineers, Fire Protection Engineers and Emergency Response Personnel alike. This research explores existing correlations, identifies their limitations and proposes a simplified methodology that links key parameters found to govern the internal post-flashover compartment fire to the heat flux potentially imposed on the exterior façade. Existing correlations addressing the effect of compartment fires on the insult to the external structure have largely been compiled by Law and are summarised in the form of a design manual for bare external structural steel [1]. Formulated in the 1970s, these correlations are based on the combined findings of several different experimental tests devised to investigate component phenomena of compartment fires and external flaming, forming an analytical model which is mostly empirical in nature. The methodology is convoluted and has several inherent assumptions which give rise to various limits of applicability however it is currently still used in structural-fire design, but best known as Annex B of both Eurocodes 1 and 3 [2,3]. As part of the present research, full-scale fire tests are conducted in situ, in a highly instrumented high-rise building, to provide high-resolution measurements of several internal compartment fire characteristics during a post-flashover fire in a modern, realistically-furnished compartment. External high resolution instrumentation in the main test also provides detailed measurements of the external flaming and distribution of heat flux incident on the façade. The tests provide realistic benchmark scenario data for comparing physical measurements against the analytical Law Model, the difference in which allows for an evaluation of the assumptions used in the model, which are often defined as ‘conservative’ in nature from the perspective of structural design. A detailed sensitivity study of the main input parameters in the Law Model allows for the identification of parameters of pivotal influence on the resultant heat flux incident on the plane of the external façade. Analysis of the Law Model and its underlying experimental basis also enables the identification of several limits of applicability of the model. Combined, these assessments show the analytical model can be stripped of unnecessary complexity and a Simplified Model is proposed with clear bounds of applicability. The proposed model describes the distribution of heat flux to the façade above a compartment opening and features only parameters of key importance, where low-dependency parameters are grouped into associated error bars. This results in a model that can be applied in the design of several building components that fall in the plane of the façade, such as structural elements, façade cladding and window arrangements. Its ease of implementation renders the model more widely accessible to different factions of the Fire Engineering Community. Furthermore, analysis of the Law Model identifies further parameters of potential importance that have, as of yet, not been addressed. A preliminary investigation conducted using Computational Fluid Dynamics (CFD) tools shows that variation in some parameters – that are not individually accounted for in the Law Model – may influence the compartment fire conditions, the consequent external flaming and the resultant external heat exposure. Therefore, it is recommended that further comprehensive experimental research be conducted into the potential influence of the identified parameters.
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Kahrmann, Steffen. "Experimental analysis of fire-induced flows for the fire-safe design of double-skin facades." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/25422.
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Today, ever changing and advancing techniques of construction are constantly pushing the envelope of structural possibilities in the built environment. Although not new, the concept of Double-Skin Façades (DSF) finds increasing implementation with the advent of sustainable construction, aiming to reduce energy consumption to condition buildings whilst improving indoor air quality. As is the case with the traditional concept of the compartment fire, methodologies and assumptions on which our general understanding of the fire problem is based, did fundamentally not change. Inherently bound to this, is the concept of compartmentalisation, prescribing measures to avoid horizontal and vertical fire spread in buildings. A DSF, most commonly featuring a ventilated cavity between curtain wall and the secondary glass façade at an offset, is prone to drastically alter fire and smoke behaviour once able to enter. Unlike curtain walls, the chimney-like aspect ratio of such façades is able to trap fire and combustion gases within the cavity, potentially compromising the integrity of the building perimeter above the fire. The current approach to this issue tends to focus on using non-combustible construction materials and the installation of sprinkler systems to avoid breakage of window panes in the first place. Another topic of interest is the weak connection between floor slab and curtain wall which can allow vertical fire spread to adjacent floors. Research has also been discussing the use of mullions to deflect the fire plume away from the façade. Even if useful in DSF’s, aesthetics and problems with functionality will most likely prevent mullions from being introduced into the DSF. However, very little relevant research actually investigated the fire-induced flow structure under these conditions so that properly informed design decisions can be made. The project at hand aims to understand hazards to the floors above and below the fire floor by experimentally investigating the governing processes by means of large-scale fire testing and small-scale salt-water modelling (SWM). The gathered data shall serve as a basis to discuss current spandrel and cavity design decisions. Results have been compared in terms of dimensionless numbers and demonstrate complex interactions between DSF cavity width and spandrel height, encouraging a discussion about the need of further research of this topic.
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Pillet-Shore, Danielle Marguerite. "Coming together creating and maintaining social relationships through the openings of face-to-face interactions /." Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1619144141&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Ramelot, Jacques. "Cle des preventions therapeutiques pour un equilibre cranio-maxillo-mandibulaire : arguments tires d'un suivi de 4 annees, par analyse multifactorielle." Paris 5, 1991. http://www.theses.fr/1991PA05M122.
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Wang, Jialu. "Facile Methods for the Analysis of Lysophosphatidic Acids in Human Plasma." PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2235.
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Lysophosphatidic acid (LPA) influences many physiological processes, such as brain and vascular development. It is associated with several diseases including ovarian cancer, breast cancer, prostate cancer, colorectal cancer, hepatocellular carcinoma, multiple myeloma atherosclerotic diseases, cardiovascular diseases, pulmonary inflammatory diseases and renal diseases. LPA plasma and serum levels have been reported to be important values in diagnosing ovarian cancer and other diseases. However, the extraction and quantification of LPA in plasma are very challenging because of the low physiological concentration and similar structures of LPA to other phospholipids. Many previous studies have not described the separation of LPA from other phospholipids, which may make analyses more challenging than necessary.
We developed an SPE extraction method for plasma LPA that can extract LPA at high purity. We also developed an HPLC post-column fluorescence detection method that allows the efficient quantification of LPA. These methods were used in a clinical study for ovarian cancer diagnosis to help validate LPA as a biomarker of ovarian cancer. Moreover, molecular imprinted polymers (MIPs) were designed and synthesized as material for the improved extraction of LPA. Compared to the commercially available materials, the MIP developed shows enhanced selectivity for LPA. The extraction was overall relatively more efficient and less labor-intensive.
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Pan, Qiujing. "Deterministic and Probabilistic Assessment of Tunnel Face Stability." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAI044.
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The main work for Qiujing PAN’s PhD thesis is to develop the stability analysis for underground structures, which contains two parts, deterministic model and probabilistic analysis. During his 1st year of PhD research, he has mainly finished the deterministic model study. In the 2nd year, I developed a probabilistic model for high dimensional problemsIn the contemporary society, the utilization and exploitation of underground space has become an inevitable and necessary measure to solve the current urban congestion. One of the most important requirements for successful design and construction in tunnels and underground engineering is to maintain the stability of the surrounding soils of the engineering. But the stability analysis requires engineers to have a clear ideal of the earth pressure, the pore water pressure, the seismic effects and the soil variability. Therefore, the research aimed at employing an available theory to design tunnels and underground structures which would be a hot issue with high engineering significance. Among these approaches employed to address the above problem, limit analysis is a powerful tool to perform the stability analysis and has been widely used for real geotechnical works. This research subject will undertake further research on the application of upper bound theorem to the stability analysis of tunnels and underground engineering. Then this approach will be compared with three dimensional analysis and experimental available data. The final goal is to validate new simplified mechanisms using limit analysis to design the collapse and blow-out pressure at the tunnel face. These deterministic models will then be used in a probabilistic framework. The Collocation-based Stochastic Response Surface Methodology will be used, and generalized in order to make possible at a limited computational cost a complete parametric study on the probabilistic properties of the input variables. The uncertainty propagation through the models of stability and ground movements will be evaluated, and some methods of reliability-based design will be proposed. The spatial variability of the soil will be taken into account using the random field theory, and applied to the tunnel face collapse. This model will be developed in order to take into account this variability for much smaller computation times than numerical models, will be validated numerically and submitted to extensive random samplings. The effect of the spatial variability will be evaluated
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Olausson, Erik. "Face Recognition for Mobile Phone Applications." Thesis, Linköping University, Department of Science and Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11850.
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Att applicera ansiktsigenkänning direkt på en mobiltelefon är en utmanande uppgift, inte minst med tanke på den begränsade minnes- och processorkapaciteten samt den stora variationen med avseende på ansiktsuttryck, hållning och ljusförhållande i inmatade bilder.
Det är fortfarande långt kvar till ett färdigutvecklat, robust och helautomatiskt ansiktsigenkänningssystem för den här miljön. Men resultaten i det här arbetet visar att genom att plocka ut feature-värden från lokala regioner samt applicera en välgjord warpstrategi för att minska problemen med variationer i position och rotation av huvudet, är det möjligt att uppnå rimliga och användbara igenkänningsnivåer. Speciellt för ett halvautomatiskt system där användaren har sista ordet om vem personen på bilden faktiskt är.
Med ett galleri bestående av 85 personer och endast en referensbild per person nådde systemet en igenkänningsgrad på 60% på en svårklassificerad serie testbilder. Totalt 73% av gångerna var den rätta individen inom de fyra främsta gissningarna.
Att lägga till extra referensbilder till galleriet höjer igenkänningsgraden rejält, till nästan 75% för helt korrekta gissningar och till 83,5% för topp fyra. Detta visar att en strategi där inmatade bilder läggs till som referensbilder i galleriet efterhand som de identifieras skulle löna sig ordentligt och göra systemet bättre efter hand likt en inlärningsprocess.
Detta exjobb belönades med pris för "Bästa industrirelevanta bidrag" vid Svenska sällskapet för automatiserad bildanalys årliga konferens i Lund, 13-14 mars 2008.
Applying face recognition directly on a mobile phone is a challenging proposal due to the unrestrained nature of input images and limitations in memory and processor capabilities.
A robust, fully automatic recognition system for this environment is still a far way off. However, results show that using local feature extraction and a warping scheme to reduce pose variation problems, it is possible to capitalize on high error tolerance and reach reasonable recognition rates, especially for a semi-automatic classification system where the user has the final say.
With a gallery of 85 individuals and only one gallery image per individual available the system is able to recognize close to 60 % of the faces in a very challenging test set, while the correct individual is in the top four guesses 73% of the time.
Adding extra reference images boosts performance to nearly 75% correct recognition and 83.5% in the top four guesses. This suggests a strategy where extra reference images are added one by one after correct classification, mimicking an online learning strategy.
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Wileman, James Michael. "Dynamic analysis of eccentric mechanical face seals." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/17343.
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Riaz, Muhammed Shahjahan. "Analysis of discriminant features for face recognition." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325242.
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Paras, Carrie. "An analysis of the multiple face phenomenon /." abstract and full text PDF (UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1446791.
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Thesis (M.A.)--University of Nevada, Reno, 2007."May, 2007." Includes bibliographical references (leaves 29-33). Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2008]. 1 microfilm reel ; 35 mm. Online version available on the World Wide Web.
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Duffner, Stefan. "Face image analysis with convolutional neural networks." [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:bsz:25-opus-48350.
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Chinthapalli, Vamsi Krishna. "Face shape analysis in people with epilepsy." Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10043826/.
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Stereophotogrammetry and dense surface modelling are novel techniques that have been used to study face shape in genetic and neurodevelopmental disorders. In people with epilepsy, it has been recognised that the condition may be associated with underlying structural variants or malformations of cortical development in some cases. Here I recruited 869 people with epilepsy or unaffected relatives and control subjects to study face shape. I sought to explore whether face shape and symmetry, using new metrics for each, could help to predict those people with epilepsy who may have potential underlying genetic or structural causes. My reproducibility studies found that stereophotogrammetry and dense surface modelling were susceptible to error from changes in head position or face expression, but not from camera calibration, image acquisition and image landmarking. The next study found that in people with epilepsy, a measurement of atypical face shape, Face Shape Difference (FSD), was significantly increased in those with pathogenic structural variants compared to those without pathogenic structural variants. The FSD value was used to predict the presence of pathogenic structural variants with a sensitivity of 66- 80% and specificity of 65-78%. Body mass index affects face shape in a partly predictable manner. The effect of body mass index differences was controlled for in a further analysis. I then analysed facial asymmetry and showed that it was increased in people with developmental lesions in the brain but not in people with pathogenic structural variants. A final study showed that stereophotogrammetry, dense surface modelling, FSD and reflected FSD could be used to study a single genetic disorder associated with epilepsy, to find previously unrecognised face shape changes. Stereophotogrammetry and dense surface modelling therefore appear to be promising tools to aid both in discovery of underlying causes for epilepsy and in understanding of such causes in terms of facial development.
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Patel, Vatsa Sanjay. "Masked Face Analysis via Multitask Deep Learning." University of Dayton / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1619637677725646.
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Clement, Stephen J. "Sparse shape modelling for 3D face analysis." Thesis, University of York, 2014. http://etheses.whiterose.ac.uk/8248/.
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This thesis describes a new method for localising anthropometric landmark points on 3D face scans. The points are localised by fitting a sparse shape model to a set of candidate landmarks. The candidates are found using a feature detector that is designed using a data driven methodology, this approach also informs the choice of landmarks for the shape model. The fitting procedure is developed to be robust to missing landmark data and spurious candidates. The feature detector and landmark choice is determined by the performance of different local surface descriptions on the face. A number of criteria are defined for a good landmark point and good feature detector. These inform a framework for measuring the performance of various surface descriptions and the choice of parameter values in the surface description generation. Two types of surface description are tested: curvature and spin images. These descriptions, in many ways, represent many aspects of the two most common approaches to local surface description. Using the data driven design process for surface description and landmark choice, a feature detector is developed using spin images. As spin images are a rich surface description, we are able to perform detection and candidate landmark labelling in a single step. A feature detector is developed based on linear discriminant analysis (LDA). This is compared to a simpler detector used in the landmark and surface description selection process. A sparse shape model is constructed using ground truth landmark data. This sparse shape model contains only the landmark point locations and relative positional variation. To localise landmarks, this model is fitted to the candidate landmarks using a RANSAC style algorithm and a novel model fitting algorithm. The results of landmark localisation show that the shape model approach is beneficial over template alignment approaches. Even with heavily contaminated candidate data, we are able to achieve good localisation for most landmarks.
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Boulkenafet, Z. (Zinelabidine). "Face presentation attack detection using texture analysis." Doctoral thesis, Oulun yliopisto, 2018. http://urn.fi/urn:isbn:9789526219257.
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Abstract In the last decades, face recognition systems have evolved a lot in terms of performance. As a result, this technology is now considered as mature and is applied in many real world applications from border control to financial transactions and computer security. Yet, many studies show that these systems suffer from vulnerabilities to spoofing attacks, a weakness that may limit their usage in many cases. A face spoofing attack or presentation attack occurs when someone tries to masquerade as someone else by presenting a fake face in front of the face recognition camera. To protect the recognition systems against attacks of this kind, many face anti-spoofing methods have been proposed. These methods have shown good performances on the existing face anti-spoofing databases. However, their performances degrade drastically under real world variations (e.g., illumination and camera device variations). In this thesis, we concentrate on improving the generalization capabilities of the face anti-spoofing methods with a particular focus on the texture based techniques. In contrast to most existing texture based methods aiming at extracting texture features from gray-scale images, we propose a joint color-texture analysis. First, the face images are converted into different color spaces. Then, the feature histograms computed over each image band are concatenated and used for discriminating between real and fake face images. Our experiments conducted on three color spaces: RGB, HSV and YCbCr show that extracting the texture information from separated luminance chrominance color spaces (HSV and YCbCr) yields to better performances compared to gray-scale and RGB image representations. Moreover, to deal with the problem of illumination and image-resolution variations, we propose to extract this texture information from different scale images. In addition to representing the face images in different scales, the multi-scale filtering methods also act as pre-processing against factors such as noise and illumination. Although our obtained results are better than the state of the art, they are still far from the requirements of real world applications. Thus, to help in the development of robust face anti-spoofing methods, we collected a new challenging face anti-spoofing database using six camera devices in three different illumination and environmental conditions. Furthermore, we have organized a competition on the collected database where fourteen face anti-spoofing methods have been assessed and comparedTiivistelmä Kasvontunnistusjärjestelmien suorituskyky on parantunut huomattavasti viime vuosina. Tästä syystä tätä teknologiaa pidetään nykyisin riittävän kypsänä ja käytetään jo useissa käytännön sovelluksissa kuten rajatarkastuksissa, rahansiirroissa ja tietoturvasovelluksissa. Monissa tutkimuksissa on kuitenkin havaittu, että nämä järjestelmät ovat myös haavoittuvia huijausyrityksille, joissa joku yrittää esiintyä jonakin toisena henkilönä esittämällä kameralle jäljennöksen kohdehenkilön kasvoista. Tämä haavoittuvuus rajoittaa kasvontunnistuksen laajempaa käyttöä monissa sovelluksissa. Tunnistusjärjestelmien turvaamiseksi on kehitetty lukuisia menetelmiä tällaisten hyökkäysten torjumiseksi. Nämä menetelmät ovat toimineet hyvin tätä tarkoitusta varten kehitetyillä kasvotietokannoilla, mutta niiden suorituskyky huononee dramaattisesti todellisissa käytännön olosuhteissa, esim. valaistuksen ja käytetyn kuvantamistekniikan variaatioista johtuen. Tässä työssä yritämme parantaa kasvontunnistuksen huijauksen estomenetelmien yleistämiskykyä keskittyen erityisesti tekstuuripohjaisiin menetelmiin. Toisin kuin useimmat olemassa olevat tekstuuripohjaiset menetelmät, joissa tekstuuripiirteitä irrotetaan harmaasävykuvista, ehdotamme väritekstuurianalyysiin pohjautuvaa ratkaisua. Ensin kasvokuvat muutetaan erilaisiin väriavaruuksiin. Sen jälkeen kuvan jokaiselta kanavalta erikseen lasketut piirrehistogrammit yhdistetään ja käytetään erottamaan aidot ja väärät kasvokuvat toisistaan. Kolmeen eri väriavaruuteen, RGB, HSV ja YCbCr, perustuvat testimme osoittavat, että tekstuuri-informaation irrottaminen HSV- ja YCbCr-väriavaruuksien erillisistä luminanssi- ja krominanssikuvista parantaa suorituskykyä kuvien harmaasävy- ja RGB-esitystapoihin verrattuna. Valaistuksen ja kuvaresoluution variaation takia ehdotamme myös tämän tekstuuri-informaation irrottamista eri tavoin skaalatuista kuvista. Sen lisäksi, että itse kasvot esitetään eri skaaloissa, useaan skaalaan perustuvat suodatusmenetelmät toimivat myös esikäsittelynä sellaisia suorituskykyä heikentäviä tekijöitä vastaan kuten kohina ja valaistus. Vaikka tässä tutkimuksessa saavutetut tulokset ovat parempia kuin uusinta tekniikkaa edustavat tulokset, ne ovat kuitenkin vielä riittämättömiä reaalimaailman sovelluksissa tarvittavaan suorituskykyyn. Sen takia edistääksemme uusien robustien kasvontunnistuksen huijaamisen ilmaisumenetelmien kehittämistä kokosimme uuden, haasteellisen huijauksenestotietokannan käyttäen kuutta kameraa kolmessa erilaisessa valaistus- ja ympäristöolosuhteessa. Järjestimme keräämällämme tietokannalla myös kansainvälisen kilpailun, jossa arvioitiin ja verrattiin neljäätoista kasvontunnistuksen huijaamisen ilmaisumenetelmää
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Bartlett, Marian Stewart. "Face image analysis by unsupervised learning and redundancy reduction /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1998. http://wwwlib.umi.com/cr/ucsd/fullcit?p9907603.
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Moucho, Mohammadkarim, and Nader Farhat. "Användning av glas i kontorsbyggnader : Fokus på energi- och koldioxidutsläpp." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Byggnadsteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-36430.
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Syfte: Att undersöka effekterna vid ersättning av större delar av fasader ikontorsbyggnader med glas, där fokus ligger på energianvändning samtkoldioxidutsläpp. Metod: Kvalitativa semistrukturerade intervjuer, litteraturstudier och dokumentanalys. Resultat: En kontorsbyggnad studerades med hänsyn till den specifikaenergianvändningen och koldioxidutsläppen. Glasarean och fasadarea beräknades förden befintliga byggnaden. Sedan utökades glasarean i fasaden från 30 % till 50respektive 70 %. Resultatet visade att en ökning från 30 % till 50 % minskade denspecifika energianvändningen för samtliga fyra energiberäkningar som utfördes iGöteborg, Lund, Stockholm och Umeå. Däremot ökade den specifikaenergianvändningen för samtliga fall vid en ökning från 50 % till 70 %. Vid analyseringav koldioxidutsläppen fick man fram att koldioxidhalten alltid minskade vid ökning avglasarea. Konsekvenser: Rapporten visar tydligt att det finns ett problem gällandeenergiförbrukning och koldioxidutsläpp idag. Byggregler och råd ska följas utavbyggbranschen för att uppnå målen som EU har satt upp. Studien visar att det finns etttydligt samband mellan koldioxidutsläppen och ökningen av glasarean dock saknadesdetta samband för energianvändningen. Begränsningar: Arbetet begränsas till att undersöka en kontorsbyggnad medbetongstomme belägen i Göteborg, Stockholm, Lund och Umeå. Glasets arkitektoniskaperspektiv behandlas inte och påverkar därav inte val eller placering av glaspartier,glaset har inte några bärande egenskaper.Purpose: To investigate the effects of replacing major parts of facades in officebuildings with glass, focusing on the energy use and the carbon dioxide emissions Method: Qualitative semi- structured interviews, literature studies and documentanalysis. Findings: An office building was studied with regard to the specific energy use andcarbon dioxide emissions. The glass area and façade area were calculated for theexisting building. Then the glass area was expanded from 30 % to 50% and 70%respectively. The result showed that an increase from 30% to 50% decreased thespecific energy use for all four energy calculations carried out in Gothenburg, Lund,Stockholm and Umeå. On the other hand, the specific energy use for all cases increasedwhen expanding the glass area from 50% to 70%. When analyzing carbon dioxideemissions, it was found that the carbon dioxide content always reduced as a result ofthe increasing glass area.Implications: The report clearly shows that there is a problem regarding energyconsumption and carbon dioxide emissions today. Building rules and advice should befollowed by the construction industry in order to achieve the goals set by the EU. Thestudy shows that there is a clear connection between carbon dioxide emissions and theincrease in the glass area, however, this connection was lacking for the energy use. Limitations: The work is limited to investigating an office building with concreteframes located in Gothenburg, Stockholm, Lund and Umeå. The architecturalperspective of the glass is not considered and therefore it does not influence theselection nor does placement of the glass portions, the glass have no bearing attributes.
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Kose, Neslihan. "Leurrage et dissimulation en reconnaissance faciale : analyses et contre attaques." Thesis, Paris, ENST, 2014. http://www.theses.fr/2014ENST0020/document.
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La Reconnaissance automatique des personnes est devenue un sujet de plus en plus important avec l'augmentation constante des besoins en sécurité. De nombreux systèmes biométriques existent. Ils utilisent différentes caractéristiques humaines. Parmi tous les traits biométriques, la reconnaissance faciale inclut des aspects positifs en termes d'accessibilité et de fiabilité. Dans cette thèse, deux défis en reconnaissance faciales sont étudiés. Le premier est le leurrage. Le leurrage en reconnaissance faciale est présenté. Des contre-mesures permettant d'améliorer les systèmes actuels sont proposés. A cet effet, les attaques basées sur des photographies 2D ou des masques 3D sont analysées. Le second défi exploré dans cette thèse est lié aux variations dues à des altérations du visage (i.e. chirurgie plastique), maquillage et accessoires pour le visage (e.g. occultations par la présence de lunettes). L'impact de ces variations en reconnaissance de visage est étudiée séparément. Ensuite, des techniques robustes contre les variations de camouflage sont proposéesHuman recognition has become an important topic as the need and investments for security applications grow continuously. Numerous biometric systems exist which utilize various human characteristics. Among all biometrics traits, face recognition is advantageous in terms of accessibility and reliability. In the thesis, two challenges in face recognition are analyzed. The first one is face spoofing. Spoofing in face recognition is explained together with the countermeasure techniques that are proposed for the protection of face recognition systems against spoofing attacks. For this purpose, both 2D photograph and 3D mask attacks are analyzed. The second challenge explored in the thesis is disguise variations, which are due to facial alterations, facial makeup and facial accessories (occlusions). The impact of these disguise variations on face recognition is explored, separately. Then, techniques which are robust against disguise variations are proposed
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Steward, Julian Holmes. "Elastic analysis of load distribution in wide-faced spur gears." Thesis, University of Newcastle Upon Tyne, 1989. http://hdl.handle.net/10443/804.
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The load distribution across the contact line(s) of spur gears is essential for the gear designer to be able to accurately stress gears for a given application. Existing gear standards (eg BS 436, AGMA 218 DIN 3990) use a thin slice (2D) model of the meshing gear teeth to estimate the contact line load distribution. This approach clearly fails to model properly teeth subjected to mal-distributed loads, since the buttressing effect of adjacent tooth sections tends to flatten the load distribution. Non-linear tooth modifications such as crowning and some forms of lead correction are also inadequately modelled. This thesis sets out the theory for a 3D elastic model of widefaced- spur gears that has been implemented on a micro-computer. The required 3D contact line influence coefficients for standard form zero modification spur gears with 18 to 100 teeth have been determined by Finite Element analysis. These theoretical values have been compared with results from experiments carried out on a complete large module (18. Omm) wide-faced spur gear. The effect of the various elemental gear errors (eg pitch, profile, lead) and profile modifications have been investigated using the 3D computer model; the results compared with results predicted by the existing gear design standards. The existing gear standards use 2D tooth compliance values up to 50% less than those obtained in this work, largely due to inadequate modelling of the gear body compliance, which is most significant in gear wheels. Comparison of 3D tooth compliance values shows a large discrepancy between author's results again due to inadequate modelling of the gear body.
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Marra, Anton. "Disagreement in business negotiations : A qualitative study of BELF usage in face-to-face business negotiations." Thesis, Stockholms universitet, Engelska institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-133218.
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Knowledge of successful Business English as a lingua franca (BELF) has been recognized to be an essential element in overall business know-how (Kankaanranta & Louhiala-Salminen, 2010). In line with this notion, research has found that professionals use BELF and exploit a variety of discourse and pragmatic strategies that aid the process of cooperation and agreement so that mutual understanding can be reached (Firth, 1996; Kankaanranta & Planken, 2010; Pitzl, 2005). However, research has reported situations where business negotiators need to handle discord while maintaining a working rapport with the opposing party (e.g. Bjørge, 2012), indicating that the ability to produce the appropriate expression of disagreement is an imperative skill. Nonetheless, while there is now a better understanding of how business professionals establish common ground through using BELF, little work has been carried out on the subject on how professionals express disagreement in the same aspect (but see e.g. Bjørge, 2012; Stalpers, 1995). The present study aims to address this gap and expand the current knowledge on how business professionals express and handle disagreement in naturally-occurring face-to-face negotiations. The collected material consists of approximately 4 hours of BELF discourse recorded at a business convention in Germany. Fifteen disagreement episodes were identified, transcribed and analyzed using Conversation Analytic (CA) procedures. The present paper seeks to explore two aspects of the current topic, namely how business professionals (using BELF) express disagreement during business negotiations, and whether mitigation strategies are used when disagreement is expressed. The findings suggest that disagreements are solely content-related and are expressed in a variety of ways as they are coupled with a varied use of mitigation devices (i.e. delay and added support). Furthermore, there were instances of unmitigated expressions in the form of blunt contradictions. It is suggested that disagreements in BELF negotiations are required actions and may serve a dual purpose. The main goal of expressing disagreement is to increase clarity in cases where essential information may be misinterpreted or misguided; additionally, it indicates the speaker’s stance in the argument. Lastly, as there is a need for better knowledge of successful BELF, the present study is likely to be of interest for those who are engaged in the global business discourse community as well as researchers studying international business settings.
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Gul, Ahmet Bahtiyar. "Holistic Face Recognition By Dimension Reduction." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1056738/index.pdf.
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Face recognition is a popular research area where there are different
approaches studied in the literature. In this thesis, a holistic Principal
Component Analysis (PCA) based method, namely Eigenface method is
studied in detail and three of the methods based on the Eigenface method
are compared. These are the Bayesian PCA where Bayesian classifier is
applied after dimension reduction with PCA, the Subspace Linear
Discriminant Analysis (LDA) where LDA is applied after PCA and
Eigenface where Nearest Mean Classifier applied after PCA. All the
three methods are implemented on the Olivetti Research Laboratory
(ORL) face database, the Face Recognition Technology (FERET)
database and the CNN-TURK Speakers face database. The results are
compared with respect to the effects of changes in illumination, pose and
aging. Simulation results show that Subspace LDA and Bayesian PCA
perform slightly well with respect to PCA under changes in posehowever, even Subspace LDA and Bayesian PCA do not perform well under changes in illumination and aging although they perform better than PCA.
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Chen, Shaokang. "Robust discriminative principal component analysis for face recognition /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18934.pdf.
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