Dissertationen zum Thema „Eclaircie“
Geben Sie eine Quelle nach APA, MLA, Chicago, Harvard und anderen Zitierweisen an
Machen Sie sich mit Top-50 Dissertationen für die Forschung zum Thema "Eclaircie" bekannt.
Neben jedem Werk im Literaturverzeichnis ist die Option "Zur Bibliographie hinzufügen" verfügbar. Nutzen Sie sie, wird Ihre bibliographische Angabe des gewählten Werkes nach der nötigen Zitierweise (APA, MLA, Harvard, Chicago, Vancouver usw.) automatisch gestaltet.
Sie können auch den vollen Text der wissenschaftlichen Publikation im PDF-Format herunterladen und eine Online-Annotation der Arbeit lesen, wenn die relevanten Parameter in den Metadaten verfügbar sind.
Sehen Sie die Dissertationen für verschiedene Spezialgebieten durch und erstellen Sie Ihre Bibliographie auf korrekte Weise.
BOBAY, VERONIQUE. „Influence d'une eclaircie sur le flux de seve et la transpiration de taillis de chataignier“. Paris 11, 1990. http://www.theses.fr/1990PA112390.
Der volle Inhalt der QuelleAmiot, François. „Eclairage familial des troubles scolaires“. Rennes 1, 1992. http://www.theses.fr/1992REN1M046.
Der volle Inhalt der QuelleMosser, Sophie. „Eclairage urbain : enjeux et instruments d'action“. Paris 8, 2003. http://www.theses.fr/2003PA082307.
Der volle Inhalt der QuelleIn the context of the renewal of theories and practices in the field of "urban lighting", what is the quality of the public actions toward lighting regarding their social reception? On the one hand, our bibliographical and experimental work on the perception of the night environments reveals the limits of the paradigms of both visual comfort and the needs for lighting devices. On the other hand, our study of the doctrines and logics of action makes it possible to clarify the process of production of the city at night. Crossing these two dimensions, the regulation of the lighting policies comes out as a major stake to improve the relevance and the utility of the actions of lighting: it consists in undertaking the actions in accordance with representations of the public good that are built collectively. Our work with lighting managers and technicians makes it possible to outline instruments which could help to put this regulation into practice. It is crucial to sustain the development of these instruments
Mdawar, Ola. „Les accrus de frêne (Fraxinus excelsior L.) à l'interface environnement/sylviculture dans les Pyrénées Centrales : distribution spatiale et croissance“. Thesis, Toulouse, INPT, 2009. http://www.theses.fr/2009INPT016A/document.
Der volle Inhalt der QuelleThe changes of pastoral management practices in the Central Pyrenees are at the origin of the colonization process of grasslands by the ash (Fraxinus excelsior L.). This colonization process leads to the establishment of very dense and frequent patches of ashes in the Pyrenean landscape. The research is focused on the study of the current and future distribution of these forest patches resulting of the extension of ash trees by natural seeding called "the accrues" and on their potentiality of growth in relation to the nutritional factors which can be limiting from the point of view of an economic valorization of these new forest patches. The study of the tree growth was carried out on different levels: growth in height according to the fertility, and growth in diameter according to the climate and the competition. For this last factor, the growth was studied on in situ tree settlements without intervention and with two levels of thinning. The recognition of ash patches patterns within the mountain landscape was not possible using the traditional tools of remote sensing (SPOT) and should have require new technologies such as LIDAR or multispectral aero data which were out of reach during the PhD work. Exploratory field work has shown that at the landscape level, the presence of ash patches is a function of the topography and the land use history. With regard to the diameter growth of these increased, it is modulated by the strength of the trees, the level of competition and the climate. The maximum temperatures of April and the minimal temperatures of September or August influence the growth on the surface of tree ring. The ash reacts to the first year to thinning, especially for recent settlements and young trees. The effect of the mineral nutrition on the tree growth in height is not significant. The results on spatial pattern dynamics and the references on ash growth in a wide range of soil conditions obtained during this work constitutes a tool to help to manage ash patches within the studied area mainly with an economic point of view
Dongmo, Keumo Jiazet Joël Hans. „Acclimatation des arbres au changement des sollicitations mécaniques induites par le vent suite à une éclaircie dans un peuplement de Hêtre“. Electronic Thesis or Diss., Paris, AgroParisTech, 2022. http://www.theses.fr/2022AGPT0014.
Der volle Inhalt der QuelleWhile the tree growth potential is mainly determined by access to resources such as light or water, the distribution of produced biomass is under strong biomechanical control. The tree response to mechanical stimuli such as those induced by wind is called thigmomorphogenesis. This response has been mainly studied on very young trees under controlled condition, and only rarely in natural condition. This is the first study dealing with the tree growth in a broadleaf stand aiming to quantify the importance of thigmomorphogenetic effect as a growth factor in the silvicultural context. The experimental set-up includes forty trees divided into four groups of ten trees selected in a dense 35yrs old F. sylvatica L .stand. Each group was submitted to one of following treatments: thinning without guying, thinning with guying, guying only and controls.Considering the thigmomorphogenetic effect on the biomass allocation inside the tree, our results show that 45% of the stem volume growth and 61% of the root radial growth of thinned trees are due to wind-induced mechanical stimuli. Further, the distribution of tree ring area along the tree stem is under strong mechanosensitive control. In contrast, no effect of mechanical stimuli or thinning was observed on axial growth. Considering the explanation of the circumferential growth anisotropy, our results do not highlight a thigmomorphogenetic effect despite the identification of dominant sectors for strong winds and strains. The hypothesis put forward is that the directional variability of perceived strains is too high to induce a strongly directional growth response as it is usually the case under controlled conditions
Mostefaoui, Lotfi. „Eclairage global pour textures et surfaces non homogènes“. Limoges, 1999. http://www.theses.fr/1999LIMO0044.
Der volle Inhalt der QuelleAbou, Rahal Antoine. „Eclairage et enjeux de la dirigeance maronite au Liban“. Paris 2, 2009. http://www.theses.fr/2009PA020070.
Der volle Inhalt der QuelleFICINI, JEAN-PIERRE. „La pluralite du cadre en psychiatrie : historique, fonction, eclairage clinique“. Nantes, 1994. http://www.theses.fr/1994NANT215M.
Der volle Inhalt der QuelleCabral, Marcio. „Remodelage et Re-eclairage Pour La Création et Manipulation de Contenu Interactif“. Phd thesis, Université Nice Sophia Antipolis, 2011. http://tel.archives-ouvertes.fr/tel-01062521.
Der volle Inhalt der QuelleSTOLFI-DONATI, NOELLE. „Ombres et niveaux de gris d'une surface eclairee : classification de leurs singularites“. Nice, 1996. http://www.theses.fr/1996NICE5060.
Der volle Inhalt der QuelleLABORDE, HERVE. „Essai clinique et consentement eclaire : acceptabilise chez le malade francais hospitalise“. Bordeaux 2, 1988. http://www.theses.fr/1988BOR25379.
Der volle Inhalt der QuelleReculin, Sophie. „"Le règne de la nuit désormais va finir". L'invention et la diffusion de l'éclairage public dans le royaume de France (1697-1789)“. Thesis, Lille 3, 2017. http://www.theses.fr/2017LIL30034/document.
Der volle Inhalt der QuelleThe thesis proposes to understand the beginnings of street lighting before the invention of gas and electricity, as an object of total urban history. It analyses the process of introducing, spreading and appropriating street lighting throughout the Kingdom of France between 1697 - when public lanterns were imposed by the monarchy in the main cities of the Kingdom of France - and the revolutionary period. Although the measure was first contested by the municipalities and some of the inhabitants, from the 1770s onwards it became a mark of urbanity and an instrument of control. Based on the abundant documentation from municipal, departmental and national archives, the thesis studies the transition from "illumination" to "public lighting". The aim is to understand the decision-making process between central, provincial and local authorities, as well as the circulation of knowledge and experience in the field of lighting. The growing interest of urban populations in this new technical object led to its improvement and then to the adoption of the « réverbère » that replaced the candlelight lantern at the beginning of the Revolution. The thesis also analyses the economic, financial and social conditions of lighting development, through the figure of the entrepreneur, the street lighter and the expert. The influence of the Tourtille Sangrain company played a decisive role in the spread of urban lighting during the last third of the 18th century. Finally, it is a question of questioning the reception of innovation by city dwellers and the "cultural revolution" (D. Roche) induced in the city's night-time uses
REINEKE, JOHANNES. „Le consentement eclaire dans le cadre de la responsabilite medicale en r. F. A“. Nantes, 1989. http://www.theses.fr/1989NANT146M.
Der volle Inhalt der QuelleBouillet, Jean-Pierre. „Influence des eclaircies sur la forme du tronc anisotropie radiale et profil en long du pinus kesiya dans la region du mangoro (madagascar)“. Paris, ENGREF, 1993. http://www.theses.fr/1992ENGR0006.
Der volle Inhalt der QuelleImani, Hamidreza. „Etude comparée du droit de successions francais et iranien. Eclairage sur la place du conjoint dans l'ordre successoral“. Thesis, Lyon 3, 2014. http://www.theses.fr/2014LYO30031.
Der volle Inhalt der QuelleIt is a truth common to all that from their birth onward, on entering this world, men have rights and obligations. The existence of the right to live and the human obligations on one side and the power to possess and transmit one’s possessions on the other side prove the need to establish a legal system. On a judicial level, death is the end of someone’s existence, the cause for the separation between someone and his goods.Since death occurs to all of us, what happens to possessions whose owner is unknown? The notion of heritage encompasses all the goods and personal objects which a deceased one leaves behind or all the goods of a deceased one which are to be inherited. In terms of law, heritage is understood as the definitive transfer of the goods of a deceased to his parents or his kids under the specific conditions of his society. The transfer of goods of someone who has just died is ancient and stretches back to the first human civilizations. From the time of the primitive form of the family to its current shape, and among the different kinds of societies, there has been a legal aspect to the transfer of a deceased one to his kids. The notion of heritage is inherent to man’s nature. But one must not forget that habits and customs vary from society to society. Thus the creeds related to heritage define the rules related to private goods.Inheriting is a natural right. Some may believe that it would be better that the goods of a deceased be integrated into the common property and be kept at the disposal of the Treasury.Nevertheless, after more thorough thinking, this point of view appears to be far from being just, since heritage is completely natural and logical, like the transmitting of some of one’s parents’ physical and moral traits is, according to the natural heritage
Auguin, Daniel. „L' intéraction des proto-oncogènes de la famille des Tcl1 avec la protéine Kinase B : Eclairage structurel et dynamique“. Montpellier 2, 2004. http://www.theses.fr/2004MON20020.
Der volle Inhalt der QuelleCROIZAT-VIALLET, CHRISTOPHE. „La loi huret-serusclat et les personnes concernees par la recherche biomedicale“. Reims, 1994. http://www.theses.fr/1994REIMM019.
Der volle Inhalt der QuelleHOCHEDEZ, JEAN-FRANCOIS. „Realisatin d'une instrumentation permettant la caracterisation experimentale d'un ccd eclaire en face arriere par de la lumiere ultraviolette“. Paris 11, 1990. http://www.theses.fr/1990PA112058.
Der volle Inhalt der QuelleDemeyere, Michaël. „Noncontact dimensional metrology by triangulation under laser plane lighting : development of new ambulatory instruments / Métrologie dimensionnelle sans contact par triangulation sous éclairage par plans laser : développement de nouveaux instruments ambulatoires“. Université catholique de Louvain, 2006. http://edoc.bib.ucl.ac.be:81/ETD-db/collection/available/BelnUcetd-03092006-140258/.
Der volle Inhalt der QuelleLe, Roux-Dowlatshahi Nadège. „Concept de protection des personnes en recherche biomedicale : application dans le cadre de l'evaluation ethique des pratiques de recherche“. Paris 5, 2000. http://www.theses.fr/2000PA05N083.
Der volle Inhalt der QuelleWanlin, Guilaine. „Photodiodes pin gaa1inas ultra-rapides et sensibles a eclairage lateral pour transmissions a haut debit sur fibre optique et distribution optique-radio“. Paris 7, 1996. http://www.theses.fr/1996PA077359.
Der volle Inhalt der QuelleAlchaddoud, Alaa. „Etude du comportement électrique et photométrique des diodes électroluminescentes organiques pour l’éclairage ayant subi un vieillissement accéléré“. Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30061/document.
Der volle Inhalt der QuelleThis work reports on the study of accelerated ageing of white organic light-emitting diodes (OLEDs) for lighting. We chose to apply our study on commercial products (Philips lumiblade GL55 and OSRAM Orbeos RMW-046) to eliminate the moisture, oxygen and manufacturing process effects on the degradation mechanisms. A preliminary bibliographic study enabled us to understand the operation mechanism of the OLEDs and to analyze the different degradation causes. This one also allowed us to determine the accelerated ageing test conditions (thermal and electrical stresses). In order, to apply these particular stress conditions, we designed and realized a specific and custom-made experimental ageing bench which allows us at the same time to apply these various ageing conditions and carry out electrical and optical measurement in situ. These measurements were realized before degradations and then until a loss of 50% of the luminous flow. The evolution of the electrical and optical characteristics of the OLEDs as well as the results obtained from some additional structural analysis enabled us to establish and understand the involved mechanisms
Lemaitre, Anne-Laure. „Métacognition et personnalité chez des patients porteurs d'un gliome diffus de bas grade : un eclairage nouveau sur le potentiel plastique du cerveau humain“. Thesis, Lille 3, 2019. http://www.theses.fr/2019LIL3H059.
Der volle Inhalt der QuelleRecent findings in the field of neuropsychology have allowed to move from a localized to a dynamic network approach of brain functions. This paradigmatic shift, from a static to a reshaping brain, has been supported by the investigation of patients with low-grade glioma, a neurological tumor known to trigger processes of compensation and rescue of brain functions. However, it is currently unestablished whether this neuroplastic compensation may extend to higher-order cognitive functions, specifically those involved in self-consciousness. By using both anatomo-functional correlational methods based on lesions localization and structural disconnection approach, the purpose of this work was to assess the extent to which the neurosurgical resections of low-grade glioma affect metacognitive processes and personality traits. First, we showed that frontal lobectomies, both unilateral and bilateral, did not induce metaperceptive impairments despite the established role of the prefrontal cortex in metacognition. Likewise, our results suggest that massive surgical resections did not significantly affect personality traits. However, some of them such as positive schizotypy, and a few behavioral modifications, such as anosognosia, were found to be associated with the disruption of some white matter bundles
GIAGLARAS, PANAGIOTIS. „Modelisation du fonctionnement de cultures ornementales sous serre. Application a l'evaluation des strategies climatiques (enrichissement en co2 et eclairage artificiel) pour begonia hiemalis“. Paris 11, 1996. http://www.theses.fr/1996PA112250.
Der volle Inhalt der QuelleRachet, Bastien. „Eclairage évanescent pour l'excitation de fluorescence : détection de marqueurs individuels en environnement fluorescent pour le suivi en temps réel d'une cinétique de réaction biologique“. Grenoble INPG, 2007. http://www.theses.fr/2007INPG0184.
Der volle Inhalt der QuelleThe evanescent wave allows local excitation of fluorescent labels in the vicinity of a surface. For the use with biochip application, the energy coupling extends along a penetration depth of 100 nm into the biological sample. This property is a key advantage for kinetic measurement within a fluorescent sample. Our work establishes a theoretical evaluation of the performances for detection instruments using an evanescent excitation coupled with a standard epi-collection setup. We compare two systems either based on Total Internal Reflection or Integrated Optical Waveguide. Ln our study we pay particular attention to instrumental issues attending to develop portable devices. It has notably been showed that the control of illumination properties provides useful information in order to distinguish between immobilized probes on the surface and free label in the sample. Another key result is the individual monitoring of the fluorescence signal of 100 single molecules
Hamon, Benoit. „Fiabilité des LED : mécanismes et modélisation“. Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENI058.
Der volle Inhalt der QuelleIn the past years, white light emitting diodes (LEDs) have faced an increase of their performances combined with a decrease of their cost. In the present situation, LEDs are considered to be the light source of the future. As well as their low energy consumption, their long lifetime is one argument for a massive adoption of this technology. However, due to their long lifetime and the multitude of existing failure mechanisms (at die and package levels), the study of their reliability still remains challenging. This thesis proposes a wild range study of LED reliability, from early life failures to end of life failures. First, a new qualification test has been implemented in production to characterize and detect early failures of LED. Second, the cross study of electrical and optical variations during accelerated lifetime has been conducted. Results allowed modeling those variations and using this model for more precise lifetime estimations. Finally, failure analyses of aged samples have been conducted highlighting the failures mechanisms responsible for the measured degradations. The obtain results allow a better understanding of LED reliability through the modeling of their behavior during time and the analysis of the most critical failure mechanisms. Because lighting device reliability is a key factor, these results are useful for the LED industry
Guittard, Catherine. „La recherche biomédicale en hématologie“. Paris 5, 1997. http://www.theses.fr/1997PA05P103.
Der volle Inhalt der QuelleZarcone, Thierry. „Riza tevfik ou le soufisme "eclaire" : mecanisme de pensee et reception des idees occidentales dans le mysticisme turc sous le deuxieme regime constitutionnel ottoman (1908-1923)“. Université Marc Bloch (Strasbourg) (1971-2008), 1990. http://www.theses.fr/1990STR20008.
Der volle Inhalt der QuelleThis dissertation deals with the history of the bektashism-alevi heterodoxy during the late nineteenth and the first quarter of the present century in ottoman lands. It concerns, in a first hand, the position occupied by the islamic mystical orders and, in particular, that of the bektashism, at the time of tha tanzimat reforms and, for the most important part, during the "jeunes-turcs" regime. In a second hand, it is a study of the philosophical and mystical writing of a well-educated ottoman thinker who was also dervish, riza tevfik bolukbashi (1869-1949). A third part consists in the translation of his mystical bektashi poetry
Lebailly, Hugues. „Charles lutwidge dogson et la vie artistique victorienne : les journaux et les lettres, chroniques des excentricites d'un reclus monomaniaque ou temoignages de l'integration d'un amateur eclaire?“ Université Marc Bloch (Strasbourg) (1971-2008), 1997. http://www.theses.fr/1997STR20077.
Der volle Inhalt der QuelleDescribing charles lutwidge dodgson's journals and correspondance as an exceptionally rich account of the reception of works of art among the most enlightened fraction of the educated mid-and late-victorian british, middle-class sounds highly paradoxical, considering the still prevalent, caricatural view of his personality that would restrict 'lewis carroll"s cultural practices to a compulsive accumulation of perceptions of little girls, on the stage as well as on canvases or wet-collodion plates. And yet, an objective examination of the impressive amount of data and judgments those private papers have to offer on half a century of artistic life, from the hundreds of theatrical performances and concerts he attended to the scores of exhibitions, art galleries and studios he visited, all his life long, brings out the truly unique wealth of this hardly ever studied corpus. It enables to draw, at last, the subtle and balanced portrait of a refined amateur, no more fascinated by childish innocence than many of his contemporaries, sharing in other such typical features of the audiences of the time as the primacy afforded to staging over textuality, to performers over playwrights, to verisimilitude and finish over the artist's right to individuality of expression. His true originality lies rather in his unprejudiced approach of art, guided exclusively by his own conscience and free-will, in which were grounded his obstinate attempt at conciliating his deep christian faith with his love for a stage still subject to many ecclesiastical authorities' obloquy, his sincere denunciation of vice and its apology as a defiling of human and divine love, his perception of the chronologically or geographically distanced nude as a hymn of praise to the perfection of the creator's work
Terrom, Mickaël. „Etude d'un dispositif à fibres optiques permettant la collection, le transport et le contrôle d'un flux lumineux solaire“. Montpellier 2, 2009. http://www.theses.fr/2009MON20114.
Der volle Inhalt der QuelleNiangoran, N'goran Urbain Florent. „Optimisation de la culture de la spiruline en milieu contrôlé : éclairage et estimation de la biomasse“. Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30378/document.
Der volle Inhalt der QuelleAgriculture in a controlled environment, and in particular greenhouse cultivation, is one of the responses to the food needs of a growing population. It also makes it possible to optimize the surface of arable land and avoid pesticide and fertilizer releases harmful to man. In order to free of the cycles of the seasons and annual production, artificial lighting was introduced greenhouses since decades. Horticultural lighting followed the evolution of lighting technologies to arrive today up to LED. This lighting gives correct results, but it can be improved both in terms of quantity and spectral quality of light. From this point of view, LEDs have two main advantages : the possibility of recompose an ideal spectrum from different wavelengths and modulate the intensity of the light. Thus, they provide adapted lighting to the needs of the plant and this, in depending on the stage of its growth. The objective of this thesis is to propose an optimal lighting system for the growth of plants in a controlled environment. From the yield photosynthesis of plants, we established models of LED lighting systems optimized. These models are based on the combination of several monochrome LEDs obtained from the decomposition of the curve RQE by Pearson VII functions. We applied these theoretical results to the cultivation of a blue-green algae, the Spirulina Platensis. The choice of this plant-bacterium is based on several criteria : short crop cycle, applications in cosmetics, medicine and high nutritional value. Thus, we were able to study the influence of culture parameters such as light intensity, photoperiod, temperature on its growth. In addition, we have implemented two methods based on optical reflectance to quantify the biomass produced by spirulina
Girard, Joffrey. „Modélisation de l'éblouissement d'inconfort dans des situations dynamiques“. Thesis, Paris Est, 2019. http://www.theses.fr/2019PESC2058.
Der volle Inhalt der QuelleThe discomfort glare is defined as the sensation of discomfort felt by an observer in presence of light sources, without necessary impacting his visual performance. This PhD investigates this phenomen on in the context of outdoor lighting. Although many models of discomfort glare have been proposed in the literature, there is no consensus in outdoor lighting. Moreover, most of these models have been developed to predict the discomfort glare level from one static light source in the visual field. In outdoor lighting, the road user is usually moving with multiple sources around him. To study this phenomenon in dynamic multi-source situations, seven psychovisual experimentations were carried out in the laboratory with panels of participants. These experimentations proposed multi-source stimuli having their characteristics (luminance, apparent size, position) that periodically varied. From the experimental data, a model was developed which predict the probability of four discomfort glare levels. It depends on the photometric and geometric characteristics of the visual scene
Baillot, Raphaël. „Méthodologie d'analyse de défaillance pour l'évaluation de la fiabilité de diodes électroluminescentes GaN“. Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14364/document.
Der volle Inhalt der QuelleGaN-based LEDs are currently used in a wide range of applications as solid-state lighting, backlighting or full-color displays. Up to date, polymer-based packaging degradation mechanisms are not fully understood. The purpose of this thesis is to work out a methodology of failure analysis contributing towards reliability estimation of GaN-based LEDs under active storage ageing tests. The methodology consists in extracting electro-optical failure signatures to locate degraded zones. A second step is based on physico-chemical analyses used to both confirm failure mechanisms and reduce the number of components to study. Environmental ageing tests (1500h/85°C/Inominal) have been performed on low power InGaN/GaN MQW LEDs (30mW) through a project in collaboration with the French Space Agency (CNES). A 65% loss of optical power has been reported after ageing. Through the methodology, we have found out that optical loss is due to the silicone oil (i.e. chip coating) polymerization activated by photothermal mechanism thereby involving both a 69% fluorescence emission loss and a strong decrease of LED light absorption (90%). A similar failure mechanism has been reported on YAG:Ce/silicone oil mixture located in phosphor converted high power white InGaN/GaN MQW LEDs (CEA-LETI collaboration - Solid-State Lighting project). Fluorescence efficiency has increased (1,2% at 450 nm) despite both strong absorption (94%) and fluorescence emission (85%) losses. Actually, silicone oil polymerization has induced a 45% loss of optical power and a 3,6% yellow shift of white light. Such drift has been linked to both a 5nm blue shift of UV fluorescence involving a 2nm red shift of LED light
Luong, Thi Ngoc Huyen. „La politique d'éclairage public à Hà-Nội : Jeux d'acteurs et enjeux urbains“. Phd thesis, INSA de Lyon, 2012. http://tel.archives-ouvertes.fr/tel-00743709.
Der volle Inhalt der QuelleArexis, Boisson Lydie. „Étude et optimisation d'un système d'éclairage efficace énergétiquement et adapté aux besoins de ses utilisateurs (santé, sécurité et qualité de vie)“. Toulouse 3, 2014. http://thesesups.ups-tlse.fr/2332/.
Der volle Inhalt der QuelleLight visual perception is a topic that interrogates since many years. In this research, we focus particularly on visual comfort of Humans subjected to light flickering, which may have significant health impacts. But in order to understand the visual perception of flickering, also known as luminance or chromatic temporal contrast, multiple prerequisites are required. That is why, throughout this research we have a multidisciplinary approach, and make use of knowledge about Humans: physiology of the human eye and its mechanisms of perception, neurophysiology, cognitive psychology, sociology, but also on the physics of light sources, their photometry and colorimetry, geometrical optic and optical modeling concepts, etc. The term "comfort" is often misused, that's why we first thought to accurately define the notions of comfort and distinguish terms "quality of life" and "well being" too often taken to be synonymous. To achieve this, we based our study on a cognitive approach, and oriented it in the particulary case of visual comfort, in relation to our research topic. Then, an experimental campaign on the flickering was conducted. It consisted in phenomenological study of the visual perception of flickering in different contexts: color of the environment, areas of visual perception for different experimental configurations. For this purpose, an experimental and interactive box was created. To generate the flickering, light emitting diodes ( LEDs) have been used, and a control module were used to change the two particular parameters : frequency and duty cycle. We have created a PWM signal, and have made an indirect light stimulus with a wide field. Due to the associated control module, many scenarii of flicker light have been presented to volunteers who have given their felt. The observers were selected with similar visual characteristics (emmetropic vision) and aged between 20 and 39 years. Some studies on ametropic eyes were also started. To further analyze the experimental results, an optimization method was used. It showed optimal solutions couples (frequency and duty cycle) regardless of the color of the environment and whatever axis of visual perception. We then based on these results to develop graphs of physical parameters of flickering visual comfort. Finally, a flickering application study was conducted. It consisted of comparing the color degradation of museums artworks using standard samples lit with LED power supplied with continuous mode comparing to pulse mode, and creating a constant average illumination. The damage proved to be of the same order at the end of 635000 lux. H. But as we could check the Broca Sulzer effect in our experiments (brightness felt is greater than the physical brightness), we could expect energy savings with flickering
Pacanowski, Romain. „Modes de représentation pour l'éclairage en synthèse d'images“. Thèse, Bordeaux 1, 2009. http://hdl.handle.net/1866/3279.
Der volle Inhalt der QuelleIn image synthesis, the main computation involved to generate an image is characterized by an equation named rendering equation [Kajiya1986]. This equation represents the law of energy conservation. It stipulates that the light emanating from the scene objects is the sum of the emitted energy and the reflected energy. Moreover, the reflected energy at a surface point is defined as the convolution of the incoming lighting with a reflectance function. The reflectance function models the object material and represents, in the rendering equation, a directional and energetic filter that describes the surface behavior regarding the reflection. In this thesis, we introduce new representations for the reflectance function and the incoming lighting. In the first part of this thesis, we propose two new models for the reflectance function. The first model is targeted for artists to help them create and edit highlights. Our main idea is to let the user paint and sketch highlight characteristics (shape, color, gradient and texture) in a plane parametrized by the incident lighting direction. The second model is designed to represent efficiently isotropic material data. To achieve this result, we introduce a new representation of the reflectance function that uses rational polynomials. Their coefficients are computed using a fitting process that guarantees an optimal solution regarding convergence. In the second part of this thesis, we introduce a new volumetric structure for indirect illumination that is directionally represented with irradiance vector. We show that our representation is compact and robust to geometric variations, that it can be used as caching system for interactive and offline rendering and that it can also be transmitted with streaming techniques. Finally, we introduce two modifications of the incoming lighting to improve the shape depiction of a surface. The first modification consists in warping the incoming light directions whereas the second one consists in scaling the intensity of each light source.
Réalisé en cotutelle avec l'Université Bordeaux 1 (France)
Dufay, Arthur. „High quality adaptive rendering of complex photometry virtual environments“. Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0692/document.
Der volle Inhalt der QuelleImage synthesis for movie production never stopped evolving over the last decades. It seems it has reached a level of realism that cannot be outperformed. However, the software tools available for visual effects (VFX) artists still need to progress. Indeed, too much time is still wasted waiting for results of long computations, especially when previewing VFX. The delays or poor quality of previsualization software poses a real problem for artists. However, the evolution of graphics processing units (GPUs) in recent years suggests a potential improvement of these tools. In particular, by implementing hybrid rasterization/ray tracing algorithms, taking advantage of the computing power of these processors and their massively parallel architecture. This thesis explores the different software bricks needed to set up a complex rendering pipeline on the GPU, that enables a better previsualization of VFX. Several contributions have been brought during this thesis. First, a hybrid rendering pipeline was developed (cf. Chapter 2). Subsequently, various implementation schemes of the Path Tracing algorithm have been tested (cf. Chapter 3), in order to increase the performance of the rendering pipeline on the GPU. A spatial acceleration structure has been implemented (cf. Chapter 4), and an improvement of the traversal algorithm of this structure on GPU has been proposed (cf. Section 4.3.2). Then, a new sample decorrelation method, in the context of random number generation was proposed (cf. Section 5.4) and resulted in a publication [Dufay et al., 2016]. Finally, we combined the Path Tracing algorithm with the Many Lights solution, always with the aim of improving the preview of global illumination. This thesis also led to the submission of three patents and allowed the development of two software tools presented in Appendix A
Tähkämö, Leena. „Analyse de cycle de vie pour sources de lumière artificielle : étude et analyse des cas types“. Toulouse 3, 2013. http://thesesups.ups-tlse.fr/2211/.
Der volle Inhalt der QuelleThe life cycle assessment method is standardized on a general level, but no established rules exist for conducting a life cycle assessment of light sources in detail. In most cases, it is impossible to directly compare the results of different assessments. Because of the major changes in the lighting market, it is useful to assess the environmental impacts of various light sources in similar methods. The work addresses this problem by presenting two models, a simple and an extensive one, for conducting the life cycle assessment of light sources rapidly and in a transparent, comparative way. The models are developed on the basis of four case studies presented in the work and a review to the life cycle assessment found in the literature. The case studies and the review of the previous life cycle assessments concluded similar findings despite the differences in the methods, scopes and evaluated light sources. The main conclusion of the life cycle assessments was the clear dominance of the use stage energy consumption. The environmental impacts of the use were found to be sensitive to the life of the light source and the used energy source. The dominance of the use stage was the clearest in light sources of low luminous efficacy and low manufacturing efforts and when using high-emission energy sources. The importance of the manufacturing is estimated to increase by a more detailed assessment of the manufacturing processes. The average environmental impacts of other life cycle stages, such as transport and end-of-life, were found practically negligible, but possibly notable in a certain environmental impact category
Chou, Ivone. „Dispositifs techniques et ségrégations urbaines, le cas de l’éclairage urbain à Rio de Janeiro“. Thesis, Lyon, INSA, 2013. http://www.theses.fr/2013ISAL0109/document.
Der volle Inhalt der QuelleThe night and the favela are complimentary when talking about of ambiguity, contradictory discourses and fantasies that pervade our imagination. The night is associated itself with usability, inspiration and party. But, next to the city of light, the night shows its dark side, which is based on a collective imagination, full of fears which strengthen the stigma of an undesirable territory: the favela. In relation to the design and uses of urban space in Rio de Janeiro, knowledge appears incomplete when analyzing the real impact of actions carried out in terms of lighting, the qualification, the perception and the identity of the city by night. The mechanisms that can stimulate the segregation and merge different spaces in the city, according of access or not to the public lighting services, are unknown. The originality of this work relies on the analysis of social issues of light, to understand urban fragmentation. A remarkable feature of the carioca landscape is the heterogeneous distribution of the points of light in the urban landscape. The proximity between neighborhoods and favelas, have prompted reflections on the role of the light as justice indicator or marker of injustice in the urban space. In this context we initiated our research by focusing on the social question, the lighting effects of distinct actions between the wealthy neighborhoods and favelas, and how different individuals interpret, perceive and live there. From the case analysis of neighborhoods of Botafogo, Copacabana and Ipanema, as well the favelas Santa Marta, Cantagalo and Pavão-Pavãozinho, we proceeded to analyze the segregation of proximity and the social role of the light. The representation of opposition between light/shadow, good/bad, becomes entangled in the identification and representative expressions of urban night. These embedded conflicts and the complexity of the urban landscape make the whole a singular subject
Michelot, Julien. „Développement d'une photodiode à stockage de charges vertical pour les capteurs d'image CMOS éclairés par la face arrière“. Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENT127.
Der volle Inhalt der QuelleThe continuous improvement of CMOS image sensor resolution leads to pixel size downscaling that degrades the amount of storable charges in the photodiode and the pixel’s dynamic range. Purpose of this study is to evaluate new photodiode architecture, dedicated to backside illuminated image sensor technology that maintains the same amount of storable charges despite the pixel size shrink. The disclosed solution consists in realizing a vertical pinned photodiode with silicon in-depth charge storage. The setup of a one-dimensional, pinned photodiode with symmetric junctions, analytical model allows the understanding of the physical parameters impact – cathode and anode doping concentration, distance from junction to junction – on full well capacity. On the other hand, the development of a non-self-aligned drain to the transfer gate eliminates the charge lag due to the transfer gate architecture. The optimization of technological process steps specific to vertical pinned photodiode and to transfer gate was conducted through finite elements simulations and dedicated technological trials. Finally, the feasibility of a pinned photodiode with a full well capacity of 11000 electrons has been demonstrated for a 1.4 μm pixel pitch.Keywords : CMOS Image Sensor, Vertical Pinned Photodiode, In-depth Charge Storage, Backside Illumination
Arnal, Etienne. „Modélisation et commande hiérarchisées du bâtiment pour l'amélioration des performances énergétiques, thermiques et optiques“. Phd thesis, INSA de Lyon, 2013. http://tel.archives-ouvertes.fr/tel-00873975.
Der volle Inhalt der QuelleMallet, Sandra. „Des plans-lumière nocturnes à la chronotopie. Vers un urbanisme temporel“. Thesis, Paris Est, 2009. http://www.theses.fr/2009PEST3014.
Der volle Inhalt der QuelleThis thesis is focused on the consideration on urban rhythms in planning. Indeed, faced to economic, social and technical evolutions in France, it's seems now essential to take into account the current stakes of transformations in urban planning.The analysis is centred on night-time, a particular moment of the everyday life, which undergoes numerous changes. The mutations i take into consideration are both social and spatial practices and representations
Murray, David. „Legible Visualization of Semi-Transparent Objects using Light Transport“. Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0326/document.
Der volle Inhalt der QuelleExploring and understanding volumetric or surface data is one of the challenges of Computer Graphics. The appearance of these data can be modeled and visualized using light transport theory. For the sake of understanding such a data visualization, transparent materials are widely used. If solutions exist to correctly simulate the light propagation and display semi-transparent objects, offering a understandable visualization remains an open research topic. The goal of this thesis is twofold. First, an in-depth analysis of the optical model for light transport and its implication on computer generated images is performed. Second, this knowledge can be used to tackle the problematic of providing efficient and reliable solution to visualize transparent and semi-transparent media. In this manuscript, we first introduce the general optical model for light transport in participating media, its simplification to surfaces, and how it is used in computer graphics to generate images. Second, we present a solution to improve shape depiction in the special case of surfaces. The proposed technique uses light transport as a basis to change the lighting process and modify the materials appearance and opacity. Third, we focus on the problematic of using full volumetric data instead of the simplified case of surfaces. In this case, changing only the material properties has a limited impact, thus we study how light transport can be used to provide useful information for participating media. Last, we present our light transport model for participating media that aims at exploring part of interest of a volume
Vivanloc, Vincent. „Rendu distribué sur grappe de CPU/GPU et effets d'éclairage global“. Toulouse 3, 2008. http://thesesups.ups-tlse.fr/823/.
Der volle Inhalt der QuelleVirtual Prototyping and design review require realistic real time rendering. This brings two research axes: on one hand, a real time rendering of indirect illumination effects and on the other hand, a real time distributed high resolution rendering. Simulating global illumination effects provide a sensible improvement over computer graphics currently generated by rasterisation. We were involved in indirect lighting and specular reflection rendering. Render indirect illumination is now possible for low frequency lightings. For broader frequencies, the indirect illumination rendering is limited to static scenes. This latter case requires a long preprocessing time or a lengthy mesh parametrisation. Our contribution consists in a fast reconstruction of global illumination from a photon map without any required parameterisation. The photon map is then simplified into an octree of virtual directional lights. The radiance is therefore evaluated on the fly by a graphic card to provide a real time navigation into a global illuminated scene. We also try to improve the quality of specular reflections in rasterisation to avoid a costly raytracing simulation. Indeed, rasterised reflexion are only valid for reflected items located at infinity. Thus, the quality improvement of existing solutions relies on over simplified hypothesis on scene topology. Therefore, we devised a method based on an iterative search to provide a plausible solution for near reflexions. However, the obtained accuracy is followed by some parallax phenomenon. This problem is partly limited by a local reconstruction of geometry by our projected geometry buffer. A lot of existing solutions provide high resolution real time displays. In one hand, distributed rendering hardware suffer from a fast obsolescence and have only a limited scalability. In the other hand, software distribution are more extensibility but are stuck to rough renderings. However, modifying these solutions in order to improve the quality of the rendered pictures with multipass shaders is relatively difficult : legacy software interlaces the rendering procedures with the data distribution algorithms. On the contrary, a modular architecture might improve the re-usability of a distributed system; the development of rendering methods becomes independent from any data distribution code. This is what HiD2RA tries to provide, assisted by its meta scenegraph. This implementation of remote proxy design pattern offers an extensible interface for the development of real time high quality rendering applications on display walls
Jiddi, Salma. „Photometric registration of indoor real scenes using an RGB-D camera with application to mixed reality“. Thesis, Rennes 1, 2019. http://www.theses.fr/2019REN1S015/document.
Der volle Inhalt der QuelleThe overarching goal of Mixed Reality (MR) is to provide the users with the illusion that virtual and real objects coexist indistinguishably in the same space. An effective illusion requires an accurate registration between both worlds. This registration must be geometrically and photometrically coherent. In this thesis, we propose novel photometric registration methods to estimate the illumination and reflectance of real scenes. Specifically, we propose new approaches which address three main challenges: (1) use of a single RGB-D camera. (2) estimation of both diffuse and specular reflectance properties. (3) estimation of the 3D position and color of multiple dynamic light sources. Within our first contribution, we consider indoor real scenes where both geometry and illumination are static. As the sensor browses the scene, specular reflections can be observed throughout a sequence of RGB-D images. These visual cues are very informative about the illumination and reflectance of scene surfaces. Hence, we model these cues to recover both diffuse and specular reflectance properties as well as the 3D position of multiple light sources. Our algorithm allows convincing MR results such as realistic virtual shadows and correct real specularity removal. Shadows are omnipresent and result from the occlusion of light by existing geometry. They therefore represent interesting cues to reconstruct the photometric properties of the scene. Presence of texture in this context is a critical scenario. In fact, separating texture from illumination effects is often handled via approaches which require user interaction or do not satisfy mixed reality processing time requirements. We address these limitations and propose a method which estimates the 3D position and intensity of light sources. The proposed approach handles dynamic light sources and runs at an interactive frame rate. The existence of a light source is more likely if it is supported by more than one cue. We therefore address the problem of estimating illumination and reflectance properties by jointly analysing specular reflections and cast shadows. The proposed approach takes advantage of information brought by both cues to handle a large variety of scenes. Our approach is capable of handling any textured surface and considers both static and dynamic light sources. Its effectiveness is demonstrated through a range of applications including real-time mixed reality and retexturing. Since the detection of cast shadows and specular reflections are at the heart of this thesis, we further propose a deep-learning framework to jointly detect both cues in indoor real scenes
Rousseau, Thomas. „Politiques et techniques de l’éclairage public pour répondre aux enjeux du développement durable en France : Acteurs, mutations et impacts urbains“. Thesis, Lyon, INSA, 2013. http://www.theses.fr/2013ISAL0101.
Der volle Inhalt der QuelleThe importance of having a nocturnal look on the city and of integrating artificial lighting into the urban landscape is growing at the same time as the need for a more pleasant environment in the city favouring social cohesion. At the same time, the particularly difficult social and economic climate and the ever stronger environmental considerations are forcing society and town councils to change faced with the stakes and new paradigms which are essential. In this context, urban lighting requires new approaches in the same way as the optimization of public policies devoted to transport, waste or water management. The nocturnal development in the cities cristallizes the multiple stakes and needs for change concerning the development of cultural heritage, consideration of practices, the comfort of public space, the support for cultural events, urban marking, the cost control of plans or preserving the night sky. To meet the needs and better articulate street lighting, it is imperative to take into consideration the stakes concerning the durability of street lighting. Local authorities have to find less functionalist and more qualitative approaches. It is a case of moving from street lighting to the development of urban lighting. This brings up certain questions. What are the policies and techniques of street lighting set up to meet the requirements of sustainable development ? What are the stakes ? In what way is it important to take them into account in the current socioeconomic context ? What approaches and strategies are being put into action ? Who are the key players to meet these stakes ? Are they the same ones over the whole country? Do they meet the requirements of long-term lighting ? Based on a survey of around one hundred towns in metropolitan France, our work aims at a better understanding of the consideration of durability in the public policies of lighting which seem mainly guided by economic strategies and the will to meet the requirements of the « economic » section of sustainable development. At the same time, the human and social dimension of sustainability in public lighting seems to be developing with an ever growing consideration for practices in the cities. We shall see that the tendencies of public policies on lighting are changing. What new ideas are spreading around ? What are the impacts on the city and the way of developing it ? This work also allows us to remind ourselves of the importance of lighting management in public policies and of the place of the users. The tendencies accepted by the town councils do not seem to be dictated either by the technical offer and the manufacturers or by the price of energy but rather by a combined mix of nocturnal issues depending on the size of the town, urban policies and the geographical, cultural and economic context
Challéat, Samuel. „"Sauver la nuit" : empreinte lumineuse, urbanisme et gouvernance des territoires“. Phd thesis, Université de Bourgogne, 2010. http://tel.archives-ouvertes.fr/tel-00589614.
Der volle Inhalt der QuelleNomenyo, Komla Dunyo. „Photonique UV : structuration top-down du ZnO pour une émission amplifiée et un transfert d'énergie efficace“. Thesis, Troyes, 2014. http://www.theses.fr/2014TROY0023/document.
Der volle Inhalt der QuelleThis work was conducted in the framework of the MATISSE project supported by the CPER-FEDER. Coordinated by UTT and including two other partners: Nanovation and URCA, the main project objective was the growth of high quality ZnO thin films and their valorization.ZnO is a wide band gap semiconductor with excellent optical properties. Its exciton binding energy (60meV) is one of the most important characteristics that earned to ZnO more attention despite its physical etching which is difficult to perform. Indeed, the excitonic emission of ZnO occurs approximately at 375nm, which involves the use of small structures whose achievement leads to the use of nanotechnology.Three scientific objectives were pursued: improving the extraction of the excitonic emission in ZnO thin films by engineering the photonic band gap by using photonic crystals, laser emission and control and finally, energy transfer from ZnO to QDots used as phosphors for down conversion of the UV emission to white emission. To achieve this, two technologies were used: PLD growth (Nanovation) and top-down structuring approach neglected by the scientific community.The thesis mainly deals with the structuring by electron beam lithography combined with ICP - RIE and related scientific studies. Conclusive results have been obtained such as high optical gain (>1000 cm-1) and low optical losses (<10 cm-1). We also carried out first optoelectronic components: MIS laser and MSM photodetector
Barroso, Angel. „Optimisation des systèmes d'éclairage des bâtiments de l'Université Paul Sabatier basé sur un réseau novateur de type bus continu/basse tension“. Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30345/document.
Der volle Inhalt der QuelleLight emitting diodes (LEDs) bring new possibilities to get luminaires more robust with an improved efficiency and more environmentally respectfull. Despite the benefits already achieved today, this type of luminaire still presents some possible optimizations and provides opportunities for multiple features. Through several tests, the author shows on LEDs in market that optimization points are not operated in commercial luminaires. These LEDs have been tested over a wide range of operation in photometric, electrical but also thermal to know the reproducibility of the results. Thus the influences of operating conditions including operating temperature and supply current levels were studied. To design a specific power supply for each LED type, a search of elementary LED models was performed. The objective is to take into account the main parameters of the models but also to be enough simple to be inserted into a system environment to simulate the luminaire in whole environment. Thus, the comparative study of several associations of LEDs was conducted to deduce the best compromise and propose new solutions to reduce energy consumptions and production costs, including new types of power supply
Fiori, Sandra. „Le représentation graphique dans la conception du projet d'éclairage urbain“. Phd thesis, Université de Nantes, 2001. http://tel.archives-ouvertes.fr/tel-00399027.
Der volle Inhalt der Quelle