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Remote sensing. --- Spectral reflectance. --- Transmittance.
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Ecology. --- Forests. --- Gas exchange. --- Reflectance. --- Transmittance. --- Vegetation.
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Biochemistry. --- Ecology. --- Forests. --- Gas evolution. --- Gas exchange. --- Transmittance. --- Vegetation.
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SOLAR ENERGY --- COMPUTER PROGRAMS --- CALCULATORS --- SOLAR RADIATION --- TRANSMITTANCE --- HEAT EXCHANGERS --- WEATHER --- METEOROLOGICAL DATA --- SOLAR HEATING --- DESIGN --- PASSIVE SOLAR HEATING --- ACCUMULATORS --- COMPUTERIZED SIMULATION --- HEAT GAIN --- MICROCOMPUTERS
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In Wallonia, there are many buildings and houses built in the 1960s, after World War II, that have envelopes and facades with many heat losses. Due to the poverty of the envelopes of these buildings, they are very energetically inefficient buildings (Attia et al., 2021) that need to be overheated in cold seasons to be comfortable inside. For this matter, it has been developed a methodology through infrared thermography in order to detect the poorest elements of the envelopes of these buildings for a possible renovation. This study takes as a reference a building of the University of Liege residence built in 1968. The first stage of the work consists of making a 3D model of the building. This model has been made from images obtained by drone and printing it with a 3D printer to evaluate the accuracy of the method. The second part of the work consists of estimating the thermal transmittance (U-value) of the facade of the residence through infrared thermography. This method will be compared with real monitoring of the U-value using measurement sensors and the calculation of the U-value following the ISO 9869 standard. The study aims to compare the three methods in terms of accuracy, speed, usability, and cost. The main results of this study have been to obtain the U-value by the three developed methods and the detailed comparison of these. A 3D modelling method has also been developed through images captured with the drone where good accuracy is achieved. This study provides an interesting basis for future research using drones equipped with thermal cameras to develop 3D thermal models of buildings.
Thermal transmittance (U-value) --- 3D modelling --- 3D printing --- Infrared thermography (IRT) --- Unmanned Aerial Vehicles (UAV) --- Ingénierie, informatique & technologie > Architecture --- Ingénierie, informatique & technologie > Ingénierie civile --- Ingénierie, informatique & technologie > Multidisciplinaire, généralités & autres
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Les oxydes transparents sont des matériaux présentant des propriétés opto-électroniques intéressantes pour de nombreuses applications technologiques. La majorité de ces semi-conducteurs présentent des propriétés électriques associées à un dopage de type-n. Or, le développement de matériaux de type-p présentant des propriétés physiques aussi intéressantes que leurs homologues de type-n est, encore aujourd'hui, un défi pour la communauté scientifique. Dans ce travail, nous avons développé une méthode originale de fabrication de films minces de ZnO dopé. Pour ce faire, nous avons incorporé des nanofils d’argent (AgNWs) entre deux films minces de ZnO déposés par pulvérisation cathodique. Les propriétés physiques de ces composites ont été étudiées suivant la quantité de nanofils ainsi qu’en fonction de la température de recuit de l’échantillon post-synthèse. Le but de cette étude est de mettre en évidence l’impact de l’ajout et de la diffusion des nanofils d’argent dans le ZnO sur les propriétés électriques et optiques de ce composite tout en optimisant la méthode de synthèse des échantillons. Sur base de cette méthodologie, nous avons mis en évidence trois gammes de température de recuit. Jusqu'à 300°C, nous observons une diminution de la résistance électrique suivie d'une augmentation notable à 350°C, toute deux identifiées à l’évolution des propriétés physiques du ZnO. Ensuite, pour des températures de plus de 450°C, nous observons une diminution de la résistivité grâce aux nanofils d'argent. Une valeur optimale pour la densité de nanofils a été déterminée aux alentours de 6.4 µg/cm² pour une température de recuit de 40°C associée à une résistivité de 4.31 Ωcm et une transmittance optique de 73.3% dans le domaine du visible.
Semi-conducteurs --- ZnO --- AgNW --- Dopage --- ZnO:Ag --- Pulvérisation cathodique --- Revêtement centrifuge --- Transmittance --- Résistivité --- Semiconductors --- RF magnetron sputtering --- Spin coating --- transparent conducting oxide --- Physique, chimie, mathématiques & sciences de la terre > Physique
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Buildings. --- Heat --- Power resources. --- Solar heating --- Architecture --- Design --- Architects --- Blinds --- Cloud cover --- Consumption --- Control --- Emissivity --- Government policies --- Heat gain --- Incentives --- Orientation --- Protectors --- Shades --- Shadows --- Skylights --- Solar orbits --- Solar radiation --- Space heating --- Specific heat --- Spectrum analysis --- Steady state --- Stereographic projection --- Sunlight --- Thermal conductivity --- Thermal resistance --- Transmittance --- Window glazing --- Windows --- Transmission. --- Passive systems.
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In this master thesis, the interaction of light with periodic arrays of nanometer-wide metal lines arestudied. To do so, extensive use of wave optics, waveguide and diffraction grating theories is made to better understand the interaction of light with a structure made of perfect electrical conductor (PEC) lines, both for TE and TM polarizations. In particular, we propose to gather the results of those theories in an original band structure to understand how light can couple into the array as a function of the geometrical parameters. The structure is viewed as periodic metallic waveguides simultaneously constituting a diffraction grating. The model is used to analyze quantitative numerical finite element calculations of reflectance and transmittance spectra (obtained using COMSOL Multiphysics). First, a grating of PEC lines is studied. Then an array of copper lines is analyzed and compared to the PEC lines.
reflectance --- transmittance --- array --- periodic --- metal --- copper --- interconnect --- metrology --- geometry --- pitch --- width --- height --- perfect electric conductor --- pec --- band structure --- waveguide --- diffraction --- grating --- plasmonic --- surface --- plasmon --- polariton --- semiconductor --- oxide --- scatterometry --- raman --- moore --- ruthenium --- platinum --- thin-film --- extraordinay --- optical --- transmission --- cutoff --- mode --- dispersion --- relation --- propagation --- evanescent --- nanometer --- photonic --- Physique, chimie, mathématiques & sciences de la terre > Physique
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Solar heating --- 621.47 --- 697 --- Solar heat --- Heating --- Solar thermal energy --- Engines using radiant energy --- Heating, ventilation and air conditioning of buildings --- Solar heating. --- 697 Heating, ventilation and air conditioning of buildings --- 621.47 Engines using radiant energy --- FCHART. --- FCHART (Computer program) --- Heat exchangers. --- Heat storage. --- Heating load. --- Performance --- Design --- Evaluation. --- Absorptance --- Accumulators --- Cost analysis --- Economic analysis --- Meteorological data --- Orientation --- Savings --- Solar energy --- Solar radiation --- Space heating --- Transmittance --- Water heaters --- Water heating
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This book results from a Special Issue related to the latest progress in the thermodynamics of machines systems and processes since the premonitory work of Carnot. Carnot invented his famous cycle and generalized the efficiency concept for thermo-mechanical engines. Since that time, research progressed from the equilibrium approach to the irreversible situation that represents the general case. This book illustrates the present state-of-the-art advances after one or two centuries of consideration regarding applications and fundamental aspects. The research is moving fast in the direction of economic and environmental aspects. This will probably continue during the coming years. This book mainly highlights the recent focus on the maximum power of engines, as well as the corresponding first law efficiency upper bounds.
indoor air quality --- microservice --- regression analysis --- Northern Cyprus --- environmental and technological design --- air infiltration --- IoT --- shading devices --- BIPV --- energy need optimisation --- massive simulation modelling --- thermal transmittance of enclosures --- energy efficiency --- indoor air quality index --- building energy performance --- energy consumption --- mobile app --- annual energy demand --- Passivhaus --- renewable energy integration --- dynamic building simulation --- passivhaus --- thermal comfort --- passive cooling systems --- passive strategies --- passive house --- smart ventilation --- fan-assisted ventilation
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