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Louca, K., A. Stadler, A. Raabe, and A. Ziemann. "Comparison of wind measurements between a Mini-SODAR PA0, a METEK-SODAR and a 99 m tower." Universität Leipzig, 2010. https://ul.qucosa.de/id/qucosa%3A16372.
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Doppler-SODAR measurements are commonly used to derive the vertical wind profile. One main advantage of the Mini-SODAR (from the company Remtech) is its small size and weight and therefore it is easy to handle and set up in short time. Two long-term measurements were operated in September and October 2009. A statistical comparison was made between the Mini-SODAR, the tower and the DWD-SODAR (from the company METEK) for the two measurement periods. It is presented here that the Mini-SODAR overestimates the tower measurements and also the
measurements of the DWD-SODAR. It is also shown, that the Mini-SODAR is able to determine the mean flow conditions in the lower boundary layer (up to 200 m).
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Pietschmann, Karin. "Testmessung eines Mini-SODARs im Vergleich mit einem 100m-Mast und einem Doppler-SODAR." Wissenschaftliche Mitteilungen des Leipziger Instituts für Meteorologie ; 41 = Meteorologische Arbeiten aus Leipzig … und Jahresbericht … des Instituts für Meteorologie der Universität Leipzig ; 12 (2007), S. 123-138, 2007. https://ul.qucosa.de/id/qucosa%3A15578.
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Since March 2006 the Institute of Meteorology in Leipzig (LIM) is owner of a commercial Mini-SODAR. The Mini-SODAR is very small in size and therefore mobile. It can be set up with low effort in short time at any place. The first testmeasurement was operated in June 2006 at the boundary layer field site Falkenberg that belongs to the Meteorological Observatory Lindenberg (MOL) of the German Meteorological Service (DWD) and was parallel accompanied by the measurement of a windtower and a Doppler-SODAR. The results of this six-hour-measurement are presented here. A statistical comparison between Mini-SODAR, tower data and Doppler-SODAR was performed. Also backscatter intensity and profile data from Mini-SODAR were analysed and interpreted.Seit März 2006 ist das Leipziger Institut für Meteorologie (LIM) in Besitz eines kommerziellen Mini-SODARs. Das Mini-SODAR ist auf Grund seiner Größe sehr mobil und lässt sich unter geringem Aufwand schnell an einem beliebigen Standort aufbauen. Die erste größere Testmessung und gleichzeitig Vergleichsmessung dieses Gerätes mit einem Windmast und einem Doppler-SODAR fand im Juni 2006 auf dem Grenzschichtmessfeld in Falkenberg statt, welches zum Meteorologischen Observatorium (MOL) des Deutschen Wetterdienstes (DWD) gehört. Die Auswertung dieser 6-stündigen Messung wird hier vorgestellt. Es wurde ein statistischer Vergleich zwischen Mini-SODAR, Windmast und Doppler-SODAR durchgeführt. Weiterhin wurden das Sodargramm und die gemessenen Profildaten des Mini-SODARs untersucht und interpretiert.
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Pietschmann, Karin. "Testmessung eines Mini-SODARs im Vergleich mit einem 100m-Mast und einem Doppler-SODAR." Universitätsbibliothek Leipzig, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-223342.
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Since March 2006 the Institute of Meteorology in Leipzig (LIM) is owner of a commercial Mini-SODAR. The Mini-SODAR is very small in size and therefore mobile. It can be set up with low effort in short time at any place. The first testmeasurement was operated in June 2006 at the boundary layer field site Falkenberg that belongs to the Meteorological Observatory Lindenberg (MOL) of the German Meteorological Service (DWD) and was parallel accompanied by the measurement of a windtower and a Doppler-SODAR. The results of this six-hour-measurement are presented here. A statistical comparison between Mini-SODAR, tower data and Doppler-SODAR was performed. Also backscatter intensity and profile data from Mini-SODAR were analysed and interpretedSeit März 2006 ist das Leipziger Institut für Meteorologie (LIM) in Besitz eines kommerziellen Mini-SODARs. Das Mini-SODAR ist auf Grund seiner Größe sehr mobil und lässt sich unter geringem Aufwand schnell an einem beliebigen Standort aufbauen. Die erste größere Testmessung und gleichzeitig Vergleichsmessung dieses Gerätes mit einem Windmast und einem Doppler-SODAR fand im Juni 2006 auf dem Grenzschichtmessfeld in Falkenberg statt, welches zum Meteorologischen Observatorium (MOL) des Deutschen Wetterdienstes (DWD) gehört. Die Auswertung dieser 6-stündigen Messung wird hier vorgestellt. Es wurde ein statistischer Vergleich zwischen Mini-SODAR, Windmast und Doppler-SODAR durchgeführt. Weiterhin wurden das Sodargramm und die gemessenen Profildaten des Mini-SODARs untersucht und interpretiert
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Etienne, Christian. "Réalisation et évaluation d'un sodar monostatique : étude des signatures sodars en fonction de paramètres météorologiques." Orléans, 1986. http://www.theses.fr/1986ORLE0404.
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Le but de ce travail a été la réalisation et l'évaluation d'un sodar simple monostatique à réflectivité. Les signatures très caractéristiques de la basse atmosphère fournies par ce sodar pendant trois mois, après avoir été classées sont comparées a celles obtenues aux USA, au Japon et au Canada. Puis une étude climatologique statistique comparant ces signatures sodars à différentes données météorologiques, permet d'établir des corrélations très étroites entre les différents échos sodars et les observations météorologiques principales telles que la température, l'humidité. . . Mais aussi entre l'évolution de la couche limite observée par le sodar et une donnée relevée au sol, la température du point de rosée
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Etienne, Christian. "Réalisation et évaluation d'un sodar monostatique étude des signatures sodars en fonction de paramètres météorologiques." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb375974345.
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Piper, Benjamin. "SODAR comparison methods for compatible wind speed estimation." Thesis, University of Salford, 2011. http://usir.salford.ac.uk/16501/.
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This thesis includes the results of a PhD study about methods to compare Sonic Detection And Ranging (SODAR) measurements to measurements from other instruments. The study focuses on theoretical analysis, the design of a transponder system for simulating winds and the measurement of the acoustic radiation patterns of SODARs. These methods are integrated to reduce uncertainty in SODAR measurements. Through theoretical analysis it is shown that the effective measurement volume of a range gate is 15% of a cone section based on the SODAR's Full Width Half Maximum (FWHM). Models of the beam pattern are used to calculate the ratio of air passing a turbine to that measured by a SODAR over 10 minutes with values of 3-5% found at 10ms-1. The model is used to find angles where significant Sound Pressure Levels (SPLs) occur close to a SODARs baffle giving the highest chance of fixed echoes. This is converted into an orientation guide for SODAR set-up. The design of a transponder system is detailed that aims to provide a calibration test of the processing applied by a SODAR. Testing has shown that the transponder can determine the Doppler shift equation used by a SODAR although further work is needed to make the system applicable to all SODARs. It is shown that anechoic measurements of single elements are useful for improving array models. Measurements of the FWHM and acoustic tilt angle can be achieved in the field using a tilt mechanism and a Sound Level Meter (SLM) on a 10m mast. The same mechanism can be used to calculate an effective tilt angle using the Bradley technique. It is proposed that these methods are integrated to calculate error slopes for the SODAR measurement with regards to a secondary location. It is shown that the slopes could be between 0 and 5% if the methods are fully realised and a Computational Fluid Dynamics (CFD) model is incorporated.
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Holmgren, Viktor, and Karl-Johan Vikmyr. "Detektion av fasta ekon vid vindmätning med SODAR." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Datateknik och informatik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-36490.
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Purpose – The purpose of this thesis was to facilitate the search for echoes caused by fixed objects, so called fixed echoes, when using SODAR-technique for wind measurements. Furthermore, it was investigated how fixed echoes in measurements can change based on different conditions such as: the angle of the sound beam towards the object causing the echo, the output frequency of the instrument, the air temperature and relative humidity. Method – Data was recorded on a test site in southern Sweden during February - April 2017 using two different SODAR-instruments, AQ500 and AQ510, manufactured by AQSystem. Experiments were conducted by installing the instruments at different distances and in different angles next to a met mast. The data recorded was examined for fixed echoes both by using Excel and manually and compared for correlation with the parameters mentioned. A software that uses the r-squared value for a power function adapted to the collected data was developed to detect fixed echoes. Findings – The result of the study showed that the angle of the SODAR-instrument sound beam direction compared to the met mast has a relatively high impact on the number of fixed echoes that can be easily detected. When a sound beam is aimed directly at the fixed object the echoes increased significantly compared to when the sound beams were aimed next to the mast. AQ510, that uses a higher measurement frequency than the AQ500, was less susceptible to fixed echoes when doing simultaneous measurements. Both temperature and relative humidity showed low correlation to the number of fixed echoes so the implication was that these atmospherical parameters do not affect the emergence of fixed echoes. The r-squared value for a power function adapted to the wind data turned out to be a good measure for the magnitude of a fixed echo. When the correlation coefficient of the r-squared value and the percentage of wind profiles that contained fixed echoes were calculated the value was 0,995 which is a strong positive correlation. The r-squared value is compared with a threshold value (which depends on the number of wind profiles in the data to be analysed) to determine if a fixed echo is causing disturbance. Another control is also made in the software where the measured wind values are compared with the values from the power function to find minor deviations possibly caused by fixed echoes. Implications – When the result of the thesis is considered it can help the person installing the instruments as well as the developers of the SODAR-instruments. The person installing the system can notice that fixed echoes can be decreased by rotating the instrument. The result showed the developer that by carefully selecting the right frequency the number of fixed echoes can be decreased. If neither the temperature nor the relative humidity has any impact on fixed echoes it shows the developer that the instrument can be used in varying climates. The result of the study can also be of service to wind analysts using SODAR-equipment. The software developed can be used to find fixed echoes in a more efficient way than was previously possible. Limitations – The data recordings took place during a limited period during late winter, early spring in the southern parts of Sweden which means that neither extremely high or low temperatures were measured during the campaign. The thesis is further limited by only using ”multiple axis” SODAR-instruments from AQSystem. Keywords – SODAR, wind measurements, fixed echoes, measurement instrument.Syfte – Syftet med detta examensarbete var att underlätta sökandet efter ekon från fasta objekt, så kallade "fasta ekon", vid vindmätning med SODAR-teknik. Vidare var syftet att utreda om fasta ekon framträder olika under olika förutsättningar som: mätinstrumentets ljudlobsvinkel mot objektet som ger upphov till eko, mätfrekvens, luftens temperatur och den relativa luftfuktigheten. Metod – Data samlades in med två olika SODAR-instrument, AQ500 och AQ510, från företaget AQSystem på en testplats i södra Sverige, februari – april 2017. Data samlades in genom att installera instrumenten på olika avstånd, samt roterat åt olika riktningar, från ett stationärt objekt (en ca 100 m hög mast). Denna data genomsöktes sedan, både manuellt och med hjälp av Excel, efter fasta ekon och jämfördes med tidigare nämnda parametrar. En mjukvara som kan användas för att detektera fasta ekon utvecklades. Mjukvaran använder r-kvadratvärdet för en potensfunktion anpassad till insamlade data för att avgöra storleken på ett eventuellt fast eko. Resultat – Studiens resultat visade att SODAR-instrumentets ljudlobsvinkel mot ekoalstrande objekt hade relativt hög påverkan på fasta ekons styrka. När varsin ljudlob på instrumenten riktades direkt mot masten ökade det fasta ekot jämfört mot när ljudloberna var riktade vid sidan av masten. AQ510, som mäter med en högre frekvens än AQ500, påverkades mindre av fasta ekon än vad AQ500 gjorde vid simultana mätningar. Både luftens temperatur och den relativa luftfuktigheten hade svag korrelation med fasta ekons styrka. Därför drogs slutsatsen att just dessa atmosfäriska parametrar ej påverkar hur fasta ekon uppstår. r-kvadratvärdet för en potensfunktion anpassad till vinddata visades vara ett bra mått på magnituden av ett fast eko. När korrelationskoefficienten för r-kvadratvärdet och andelen vindprofiler innehållande fasta ekon i vinddata beräknades antog den värdet 0,995 vilket visar på en stark positiv korrelation. r-kvadratvärdet jämförs med ett tröskelvärde (som beror av antalet vindprofiler i data som analyseras) för att avgöra om ett fast eko orsakar störningar. En kontroll görs även där det de uppmätta vindvärdena jämförs med potensfunktionens värden för att hitta mindre avvikelser som kan ha orsakats av fasta ekon. Implikationer – Om examensarbetets resultat tas i beaktning kan det underlätta för både installatörer och utvecklare av SODAR-instrument. För installatören visar resultatet att fasta ekon kan minskas genom att rotera mätinstrumentet. För utvecklaren visar resultatet att fasta ekon kan minskas genom att välja en lämplig mätfrekvens. Om varken luftens temperatur eller den relativa luftfuktigheten påverkar fasta ekon nämnvärt kan detta visa på att vindmätning med SODAR-instrument är brukbart i varierande klimat. Även analytiker kan ha nytta av examensarbetets resultat i form av den mjukvara som utvecklats. Mjukvaran kan användas för att på ett mer effektivt sätt än tidigare upptäcka fasta ekon. Begränsningar – Datainsamlingen genomfördes under en begränsad period under sen vinter till tidig vår i södra Sverige. Därför har varken exceptionellt låga- eller höga temperaturer mätts upp. Examensarbetet begränsas ytterligare av att endast mätinstrument från företaget AQSystem av typen "multiple axis" har använts. Nyckelord – SODAR, vindmätning, fasta ekon, mätinstrument.
Presentationen har redan skett.
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Haggagy, Mahmoud El-Nouby Adam [Verfasser], and Helmut [Akademischer Betreuer] Mayer. "A sodar-based investigation of the atmospheric boundary layer." Freiburg : Universität, 2003. http://d-nb.info/115653271X/34.
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Haggagy, Mahmoud El-Nouby Adam. "A sodar based investigation of the atmospheric boundary layer /." [S.l. : s.n.], 2003. http://www.gbv.de/dms/goettingen/367276976.pdf.
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Mandock, Randal Lee Nicholas. "A multiple beam sodar for the measurement of atmospheric turbulence." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/25869.
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Engblom, Wallberg Ian. "Making remote sensing bankable - cold climate SODAR and meteorological mast intercomparison." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-132846.
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The value of an easy to install, accurate, far-reaching measurement instrument is easily understood when dealing with setting up and monitoring wind power parks. However the use of remote sensing equipment when doing this is a subject of much discussion amongst professional experts and scholars. This is especially the case when the environmental conditions are difficult, such as areas with complex terrain or cold climate (or both), for example forested, hilly or mountainous regions in north Europe and North America. The remote sensing technology SODAR provides for detailed 3-dimensional datasets, but need a skilled analyst to make sure the measurements are realistic. This thesis is aimed at verifying the accuracy of the SODAR wind measuring equipment at two potential wind power parks in Sweden. It has been done by comparing the wind speed, wind direction and turbulence measured by an AQ Systems AQ500 Wind Finder SODAR to the wind speed, wind direction and turbulence measured by in situ anemometers mounted in nearby meteorological masts. The comparison was made by calculation of statistical parameters such as correlation and root mean square error. The results of this investigation shows that the differences in the measured quantities are site specific and that i t‟s very difficult to distinguish between differences arising from ambient conditions, the measurement method and the method of calculating comparable values. It is clear, however, that conditions such as temperature, inhomogeneous fetch and wind speed are contributors to the observed discrepancies. When compensating for these various sources of error; such as eliminating data from malfunctioning equipment, icing conditions, mast wake and forest flow disturbance, the SODAR wind speed data shows a very high correlation with the mast anemometer data, giving a correlation coefficient of around 0.90 – 0.95.Värdet av ett mätinstrument som är lätt att installera, noggrant och som kan mäta högt upp i troposfären är lätt att inse när man har att göra med att installera och övervaka vindkraftparker. Det har dock funnits en debatt om huruvida fjärranalytiska mätningar är tillräckliga för sådana ändamål i expert- och akademikerkretsar. Debatten spetsas ytterligare till då omgivningarna är svåra, exempelvis i områden med komplex terräng eller kallt klimat (eller både och), till exempel skogbeklädda, kulliga eller bergiga områden i norra Europa och Nordamerika som är aktuella för exploatering av vindkraft. Det fjärranalytiska redskapet SODAR förser exploatören med detaljerade tredimensionella datasamlingar, men kräver en erfaren och skicklig analytiker för att verkligen verifiera att mätresultaten är realistiska och tillförlitliga. Detta examensarbete har som mål att verifiera noggrannheten hos SODAR-utrustning vid två potentiella vindkraftparker i Sverige. Det har gjorts genom att jämföra vindhastighet, vindriktning och turbulens mätt med en AQ Systems AQ500 Wind Finder SODAR med vindhastighet, vindriktning och turbulens mätt med anemometrar i närbelägna meteorologiska mätmaster. Jämförelsen gjordes genom att beräkna statistiska parametrar som korrelation och standardavvikelse. Resultatet av undersökningen visar att skillnaderna i de uppmätta storheterna är specifika för varje mätplats och att det är mycket svårt att särskilja bidragen till skillnaderna mellan omgivande förhållanden, mätmetoder och beräkningsmetoder. Det står dock klart att förhållanden så som temperatur, inhomogen omgivande skrovlighet på anloppssträckan och vindhastigheten i sig själv bidrar till de observerade skillnaderna i mätresultat. Kompenseras felaktig och störd data bort så visar vindhastigheten mätt med SODAR en mycket god korrelation med mastanemometerdata, med en korrelationskoefficient omkring 0,90 – 0,95.
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Berg, Allison M. "The feasibility of sodar wind profile measurements from an oceanographic buoy." Thesis, (37 MB), 2006. http://handle.dtic.mil/100.2/ADA471871.
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Thesis (M.S.)--Massachusetts Institute of Technology at Woods Hole Oceanographic Institution, 2006."September 2006." Description based on title screen as viewed on June 8, 2010. DTIC Descriptor(s): Doppler Radar, Wind Velocity, Sound Ranging, Doppler Sonar, Buoys, Measurement, Motion, Oceanographic Equipment, Theses DTIC Identifier(s): Doppler Sodar, Sodar (Sound Detection and Ranging), ASIS Includes bibliographical references (leaf 75). Also available in print.
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Berg, Allison M. (Allison May). "The feasibility of sodar wind profile measurements from an oceanographic buoy." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/38510.
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Thesis (S.M.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Mechanical Engineering; and the Woods Hole Oceanographic Institution), 2006.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (leaf 75).
This thesis explores the feasibility of making wind speed profile measurements from an oceanographic buoy using a Doppler sodar. In the fall of 2005, we deployed a Scintec SFAS sodar on an ASIS buoy. Roughly one week of buoy motion data and one day of sodar observations were collected. Data from both this deployment, and the Martha's Vineyard Coastal Observatory, were used in conjunction with models to predict sodar performance. Results are compared for an ASIS and a 3-meter discus buoy. We also predict the yearly average probability of sodar data availability in the presence of buoy motion. We show that buoy tilting in response to wave forcing is the main factor affecting sodar performance. Our results strongly suggest that ASIS is a suitable platform for sodar measurements at sea.
by Allison M. Berg.
S.M.
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Gassner, Martin. "Untersuchung der planetaren Grenzschicht mit einem auf digitalen Betrieb umgebauten Doppler Sodar /." [S.l.] : [s.n.], 1995. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=11168.
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Schomburg, Annette. "Schallstreuung in der atmosphärischen Grenzschicht physikalische Grundlagen der akustischen Fernerkundung mit SODAR /." [S.l. : s.n.], 1998. http://deposit.ddb.de/cgi-bin/dokserv?idn=958338566.
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Donoso, Castro Nicolás Andrés. "Habilitación y validación de equipo SODAR para medición de perfiles verticales de viento." Tesis, Universidad de Chile, 2017. http://repositorio.uchile.cl/handle/2250/148371.
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Magíster en Meteorología y ClimatologíaRealizar mediciones viento en altura con técnicas tradicionales como globos cautivos y radiosondas es una tarea demandante en tiempo y recursos. Una de las soluciones a esto es la utilización de técnicas remotas como SODAR o LIDAR. El Centro de Ciencias del Clima y la Resilencia (CR)2 adquirió el año 2014 un SODAR y en el presente trabajo se presenta una habilitación del equipo mediante una campaña donde se comparan las mediciones contra Globo Cautivo, estación meteorológica en superficie y mediciones obtenidas de aviones (AMDAR). Se utilizó como referencia a la comparación realizada contra el Globo Cautivo bibliografía que reúne 20 años de mediciones SODAR \citep{Crescenti1995} utilizando estadísticos de sesgo, diferencia cuadrática media, precisión, y coeficiente de correlación. Se obtuvo resultados acorde a lo publicado en todos los estadísticos menos en el sesgo. Los resultados del trabajo indican que el SODAR, según categorías del fabricante, mide con un alcance categorizado como bueno en el lugar seleccionado y las mediciones comparan bien con respecto al globo cautivo y no tan bien para las mediciones AMDAR, siendo esto último explicado por la distancia entre las mediciones y el terreno complejo de la zona.
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Scovil, Douglas H. "An analysis of diurnal wind variability in the Santa Barbara Channel from SODAR measurements." Thesis, Monterey, California. Naval Postgraduate School, 1989. http://hdl.handle.net/10945/25670.
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Plocoste, Thomas. "Étude de la dispersion nocturne de polluants atmosphériques issus d’une décharge d’ordures ménagères. : Mise en évidence d’un îlot de chaleur urbain." Thesis, Antilles-Guyane, 2013. http://www.theses.fr/2013AGUY0700/document.
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En 2003 des mesures au spectromètre IR à Transformée de Fourier (FTIR) ont permis d'identifier et de mesurer les COV émis par la décharge à ciel ouvert de la Gabarre, principale de l'île Guadeloupe, située entre une zone urbaine et une mangrove. Ces COV ont été retrouvés (2004) la nuit dans les cités, justifiant les plaintes des riverains. Dans le cadre de cette thèse, des mesures au spectromètre de masse portatif MS 200 ont validé ces résultats du FTIR. De nouvelles mesures au MS 200 ont été menées dans toute la zone de la décharge. Les cités concernées étant à l'opposé du flux synoptique d'Alizés-Est, les facteurs météorologiques permettant la dispersion et le transport des COV de la décharge vers la zone urbaine ont été recherchés. La diminution nocturne de l'intensité des Alizés au dessus de l'ile peut laisser place à des phénomènes locaux tels les brises. L'idée d'une brise terre-mer a été éliminée. Un maillage autou~ de la décharge (cités et mangrove) avec 8 thermomètres a révélé un îlot de chaleur urbain nocturnegénérant une brise thermique d'environ Ims- I (mesurée et calculée). Avec les radiosondages Météo France et un SODAR installé dans la décharge, une très forte stabilité dans les basses couches atmosphériques de la couche limite nocturne avec une inversion de surface d'environ 120mvv apparait. Ces facteurs expliquent la pollution des cités par les COV de la décharge, Un modèlevGaussien en tenant compte a été validé par les mesures de COV.vCette étude peut être étendue à d'autres décharges à ciel ouvert et à d'autres types de traitement de polluants de déchargeIn 2003, the VOC emissions coming from "La Gabarre", the main open landfill in Guadeloupe, located in-between an urban area and a mangrove, were identified and quantified with a portable FTIR spectrometer. In 2004, COVs found at nighttime in the urban area nearby confirmed why residents complain about. As part of this thesis, portable mass spectrometer MS 200 measurements validated these FTIR figures. New systematic SM measurements have been carried on around the landfill. Since the polluted urban area stands on the opposite way of the East Trade winds synoptic flux, aIl the weather factors likely to scatter and transport the dump COVs were scrutinized. At night, the strength of the Trade winds decreases over Guadeloupe, which may give way to local phenomena such as breezes. The occurrence of land/sea breeze was eliminated. A close surveying surrounding the landfill with 8 thermometers both in the projects and in the mangrove revealed an urban heat island causing thermal breezes of about lms-l (measured and calculated). Using soundings from Meteo France, and a SODAR inside the dump, we found a great stability of the night boundary layer with a surface inversion near 120m. Pollution of the nearby urban area with landfill COVs is elucidatcd by the above factors. A transport Gaussian model is in agreement with COV measurements. This study can be extended to different open landfills and different types of polluting matters processes in dumps
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Hinojosa, Lobato Julián. "Contribució a l'estudi de l'estructura tèrmica i dinàmica de la capa fronterera atmosfèrica mitjançant un SODAR-Doppler." Doctoral thesis, Universitat de Barcelona, 2001. http://hdl.handle.net/10803/731.
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L'objectiu final d'aquesta memòria és contribuir a l'augment de la comprensió i elconeixement de l'estructura tèrmica i dinàmica de la capa fronterera atmosfèrica mitjançant
l'anàlisi de les dades proporcionades per un sodar-doppler. L'aplicació ha
estat en el camp de la dispersió de contaminants i en la millora de la qualitat i la
quantitat de les entrades meteorològiques que precisen els models destinats a aquest
ús. Per portar a bon terme el treball s'ha disposat d'una torre meteorològica instrumentada
amb diferents tipus de sensors meteorològics. A més s'han realitzat una sèrie de
campanyes experimentals: BRINV92, GLOBUS95 i VILEXP96, amb material adequat, per tal d'abastar qualsevol situació típica de la zona d'estudi.
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Eppanapelli, Lavan Kumar. "Investigation of wind potential variation at three measurement sites based on atmospheric stability and power production." Thesis, KTH, Kraft- och värmeteknologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-136935.
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As tapping energy from wind expands rapidly worldwide, it is a common procedure to locate a practicable site to extract energy from abundant wind flow by building wind farms. Comprehensive understanding of wind resource at a site is important to perform the main activities say, wind flow modeling, wind turbines micro siting, annual energy yield calculation and cost of energy estimation. Wind measuring campaigns involve using of measuring instruments such as meteorological tower instrumented with anemometers, wind vanes and temperature sensors; remote sensing devices such as SoDAR, LiDAR. These meteorological devices provide detailed information on wind behavior with respect to the height, time and temperature. These systems were proven in providing promising wind measurements even though they are susceptible to certain weather conditions. The study progressed by focusing on the wind behavior at three locations to investigate the possible factors that varies the wind character. A location with one met mast and two AQ500 SoDAR systems was considered for this project where one AQ500 is 800m away and other AQ500 is 5515m away from the point of Met mast. The location is contemplated as a decent approach to the spatial analysis of the wind resource as there is a large scope to analyze the wind character between two nearby sites and two faraway sites. Monostatic 3-beam SoDAR systems from AQ System, Sweden and 100m meteorological tower with instruments are used in this project work for collecting the wind data. One-year worth of wind data at standard 10min intervals has been collected from the three systems. This report outlines the theoretical description of project location, AQ500 SoDAR and Met mast. A detailed explanation of the data quality control and filtering methods are discussed along with respective reasons. The conclusion is drawn after performing the statistical analysis between wind speed and other parameters such as turbulent intensity, wind direction, thermal stability and temperature. Mat lab is used for computing and analyzing the wind data from three systems.
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Ito, Yoshiki. "Development of a Five-Beam Phased Array Doppler Sodar and Its Application to Observations of the Planetary Boundary Layer." 京都大学 (Kyoto University), 1997. http://hdl.handle.net/2433/202480.
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Aligné, Thomas. "Assimilation variationnelle des observations de sondeurs infrarouges hyperspectraux : correction de biais et la détection nuageuse." Toulouse 3, 2007. http://www.theses.fr/2007TOU30038.
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L'objectif de cette thèse est d'optimiser les méthodes d'assimilation de données pour l'utilisation des sondeurs infrarouges hyperspectraux. Le travail se concentre sur deux aspects essentiels : la correction de biais et la détection nuageuse. La correction de biais est une étape nécessaire qui consiste à réduire les erreurs systématiques des observations. On présente la correction de biais variationnelle (VarBC) qui est moins sensible à une contamination par les biais du modèle de prévision. Cette propriété est exploitée pour paramétriser de manière objective les biais. La détection nuageuse élimine les observations contaminées par les nuages. On identifie une boucle d'interaction entre la correction de biais et la détection nuageuse. Une nouvelle métrique permet de réduire sensiblement son impact sur l'analyse. Un nouveau schéma de détection des nuages est introduit puis validé pour des observations simulées et réelles. Il ouvre une voie vers l'assimilation des observations nuageuses.
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Pangaud, Thomas. "Assimilation des radiances des sondeurs infrarouges hyperspectraux en condition nuageuse : application à des cyclogénèses extratropicales." Toulouse 3, 2009. http://thesesups.ups-tlse.fr/772/.
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L'objectif de cette thèse est de proposer une méthode d'assimilation des observations des sondeurs infrarouges hyperspectraux en condition nuageuse. Ces observations étaient jusqu'à présent rejetées des modèles d'assimilation en raison de la nature complexe des nuages et de leursprocessus non-linéaires évoluant dans des échelles spatio-temporelles généralement inférieures à celle du modèle. L'émergence des techniques variationnelles ainsi que les améliorations réalisées en matière de modélisation nuageuse et de transfert radiatif ont relancé l'intérêt de la communauté scientifique pour l'assimilation des radiances nuageuses. Ces dernières représentent en effet une large majorité des observations des sondeurs hyperspectraux, et particulièrement dans les zones atmosphériques sensibles. La méthode d'assimilation des radiances nuageuses développée ici utilise l'information combinée des schémas de détection du CEPMMT et de caractérisation du CO2-Slicing. Pour être efficace ce schéma d'assimilation nécessite une bonne concordance des performances de détection et de caractérisation des nuages pour les deux algorithmes. La première partie de ce manuscrit a permis de montrer que les deux algorithmes sont capables de détecter de manière fiable les nuages. La bonne concordance des performances obtenues d'un schéma à l'autre justifie par ailleurs leur utilisation conjointe dans une otique d'assimilation des radiances nuageuses. Le schéma d'assimilation développé dans cette étude permet d'augmenter le volume total des observations assimilées de plus de 10% pour AIRS et de plus de 12% pour IASI, les observations supplémentaires étant majoritairement localisées dans les moyennes et hautes latitudes. La prise en compte de l'effet du nuage dans l'opérateur d'observation conduit par ailleurs à une simulation d'observations plus cohérente avec les observations réelles. Les expériences réalisées avec AIRS montrent un impact positif sur les prévisions sans être significatif pour la température,l'humidité et le vent. L'impact est significativement positif pour le géopotentiel. Les expériences préliminaires réalisées pour le sondeur IASI montrent un impact sur les prévisions plus mitigé. La prise en compte des données infrarouges issues des sondeurs hyperspectraux en condition nuageuse améliore la prévisibilité des évènements intenses pour les 2 cas d'étude traités dans ce manuscrit de thèse (tempête méditerranéenne du 26 septembre 2006 et tempête sur la bordure ouest Atlantique du 24 janvier 2009). L'assimilation opérationnelle de ce type de données pourrait ainsi permettre, entre autres, une meilleure gestion des risques et ainsi une prévention des menaces liées à ce type de situations plus efficaceThe main goal of this PhD work is to propose an approach to deal with high-spectral-resolution infrared sounders in cloudy conditions. Untill now, these observations were rejected by the data assimilation system due to the complex nature of clouds and to their non-linear processes evolving into spatiotemporal scales lower than those of the model. The emergence of variational techniques as well as improvements achieved in terms of cloud modelisation and radiative transfer revived the interests of the scientific community for the assimilation of cloudy radiances. Indeed most measurements from high-spectral-resolution infrared sounders, and in particular, in atmospheric sensitive regions, are contaminated by clouds. The approach proposed here to deal with cloudy radiances is based on the combined information from the cloud detection algorithm developped by the ECMWF and the CO2-Slicing cloud characterization algorithm. To be efficient, this scheme thus needs a good correspondance in terms of cloud detection between these two algorithms. The fist part of this study demonstrates that these two algorithms are able to detect clouds efficiently. The good correspondance in performances obtained from both algorithms justify their conjoint use to assimilate cloudy radiances. The assimilation scheme developped in this PhD work enables to increase the total amount of assimilated observations by more than 10% for AIRS and by more than 12% for IASI, additional observations are mainly located at mid to high latitudes. In addition, taking into account the cloud effect into the observation operator leads to model equivalents more consistent with true observations. Experiments performed with the AIRS sounder exhibit a positive but not significant impact on forecasts for the temperature, the humidity and the wind. The impact is significantly positive for the geopotential. Preliminary experiments performed with the IASI sounder exhibit a rather mitigated impact. Taking into account cloudy radiances from high-spectral-resolution infrared sounders improves the predictability of intense event for both study cases treated in this work (a mediterrean storm occuring on the 26th of september 2006 and an atlantic storm on the 24th of january 2009). The operational assimilation of this kind of data will certainly enable, among others, a better risk management et thus a more efficient hazard prevention
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CONIGLIO, LUCIA. "L'influenza della circolazione sinottica sul campo di vento locale in una zona costiera del Mar Tirreno." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2009. http://hdl.handle.net/2108/890.
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La circolazione nei bassi strati dell’atmosfera è il risultato dell’interazione generalmente non lineare tra la circolazione a scala sinottica e quella locale. Questa ultima è quella più frequentemente presente nelle regioni mediterranee, specie nei mesi più caldi ed ha importanti effetti sull’agricoltura e su altri aspetti delle attività umane. Essa gioca un ruolo importante nei processi di trasporto e diffusione di inquinanti in particolar modo in prossimità di aree densamente popolate dove la qualità dell’aria è importante per la salute della popolazione.
In questo lavoro le caratteristiche della circolazione locale nella zona costiera adiacente la città di Roma vengono derivate dall’analisi statistica delle misure del vento in diversi siti. I dati utilizzati comprendono sia misure di profili di vento ottenute mediante Sodar Doppler, sia misure di vento nello strato superficiale, rilevate mediante strumentazione meteorologica tradizionale. Nell’analisi sono state utilizzate anche le informazioni meteorologiche presenti nei file METAR (codice internazionale con cui vengono registrate le condizioni meteorologiche negli aeroporti) raccolti nell’aeroporto di Fiumicino dal 1994 al 2003.
Nell’analisi viene delineato l’andamento giornaliero della velocità e direzione del vento, in funzione della stagione ed è evidenziata l’esistenza di due alternative componenti notturne della circolazione locale. I dati dei radiosondaggi sono stati usati per determinare i valori del vento geostrofico. Il confronto tra la direzione del vento alle quote basse e il vento geostrofico ha permesso di stabilire l’influenza della forzante a scala sinottica nel determinare quale delle configurazioni della circolazione locale diventa maggiormente probabile, stabilendone una probabile evoluzione giornaliera. Viene quindi suggerita una metodologia che, in mancanza di un sito di radiosondaggi in prossimità dell’area di interesse, propone l’uso dei dati delle rianalisi del centro europeo ECMWF.
I risultati dell’analisi statistica del vento sono stati usati per ricostruire l’evoluzione giornaliera del campo del vento prodotto dalle forzanti locali.The low level circulation is the result of non linear interaction between mesoscale and local circulations. The latter ones often prevail in the Mediterranean regions, especially in the warmer periods, and have important effects on agriculture and other forms of human activity. For example, it plays a major role in the processes of transport and diffusion of pollutants, in particular around and in the urban areas where they may affect the air quality and the health of the population. In this work , the local circulation in Rome and in the surrounding area is studied, by using the statistical analysis of the wind field. The time series of wind data used in this study are from different sites and refer to different periods. Some of the data are recorded by the Doppler Sodar systems operating in the area; the others are routine meteorological data. Moreover, meteorological information reported in the METAR (the international code to report routine, semi-hourly weather conditions at air terminals) files, collected from 1994 to 2003 at Fiumicino Airport, were used to determine different meteorological conditions. In the analysis daily behaviour of the wind direction and intensity, as a function of the season, is highlighted and the existence of two nocturnal alternative components of the local circulation is evidenced. Rawinsonde data were used to determine geostrophic wind values. The comparison between low level and geostrophic wind directions allowed to establish the influence of the synoptic scale forcing in determining both which of the two nocturnal currents can be observed and how their directions evolve during the day. The use of data from ECMWF analysis is proposed in cases in which rawinsonde data are not available to enquire on the synoptic scale forcing. The comparison among measurements at the different sites allowed to provide a reconstruction of the wind field evolution in the area.
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KOTRONI, VASSILIKI. "Etude de la dynamique interne du jet de basses couches et de son role sur la discontinuite frontale a partir de donnees du radar st et du sodar obtenues lors de l'experience fronts 87." Clermont-Ferrand 2, 1993. http://www.theses.fr/1993CLF21514.
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Le premier objectif scientifique de la campagne d'observations fronts 87 etait d'ameliorer la comprehension des interactions dynamiques entre l'echelle synoptique, la moyenne et la petite echelle dans les systemes de fronts froids actifs. Dans ce but, le travail de cette these a consiste, d'une part a etudier la dynamique interne du jet de basses couches, une entite tres importante des fronts froids, et son role sur la discontinuite frontale, et d'autre part de diagnostiquer l'interaction de ce jet avec la convection qui lui est associee. L'originalite de cette etude consiste a l'utilisation, pour la description dynamique de ce front des donnees du radar strato-tropospherique (uhf) qui a opere pour la premiere fois lors de l'experience fronts 87. Ces donnees etaient d'autre part combinees aux mesures des radiosondages pour l'obtention de la structure thermodynamique, ainsi qu'aux mesures du sodar pour l'etude detaillee de la couche limite qui est d'ailleurs d'une importance significative dans la dynamique frontale
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Iannotti, Veronica. "Studio del fenomeno del "wind shear" e analisi dei principali sistemi di rilevamento." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/19047/.
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L'obiettivo di questa tesi di laurea è fornire un'analisi principalmente descrittiva del fenomeno del windshear, mettendo in evidenza quelle che risultano essere le condizioni meteorologiche sufficienti per la sua comparsa e gli effetti sulla stabilità dell'aeromobile provocati da una variazione del vettore vento. L'elaborato offre, inoltre, dei concetti base per il monitoraggio del windshear, attraverso lo studio di strumenti di "detection" e "warning" (quali RADAR, LIDAR e SODAR), sia da un punto di vista funzionale che matematico.
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Sukki, Firdaus Muhammad. "Optimised solar concentrator for the soar photonic optoelectronic transformer system." Thesis, Glasgow Caledonian University, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.601455.
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Malaysia is one of the countries that have started to elevate the usage of renewable - specifically solar photovoltaic (PV) - in delivering its energy needs. This thesis is divided into two main sections. The first section evaluates the solar PV installations in the residential sector in Malaysia for the past 20 years; in terms of policies, research and development activities and implementations. Recently, the Feed-in Tariff (FiT) scheme was introduced in Malaysia and based on the financial analysis, any installation of solar PV could generate a lucrative monthly income to the household owner under the FiT scheme. However, a preliminary survey indicated that Malaysians are not interested in investing in a solar PV system, mainly due to the high cost of implementation. The next section focuses on the design of solar concentrators - particularly the family of Dielectric Totally Internally Reflecting Concentrators (DTIRCs) - with the aim of achieving a low cost solar PV system. Part of the PhD project is the optimisation of the concentrator design in the Solar Photonic Optoelectronic Transformer (SPOT), the main component of SolarBrane, a static building integrated PV (BlPV) system developed by SolarEmpower Ltd. An optimised design has been proposed using a DTIRC based on the Maximum Concentration Method (MCM). It has been demonstrated via simulations that the optimised design could potentially increase the output of the SolarBrane, at the cost of having a slightly larger structure. A novel type of DTIRC family. known as the Asymmetrical DTIRC (ADTIRC). has been developed to provide additional gain at the "extrusion" plane of the concentrator, and further reducing the size of the PV cell needed. It is concluded tbat this new design generates a much higher gain compared to the concentrator in the SolarBranel. The results from the indoor experiments indicate that the ADTIRC-PV structure could increase the electrical output by 4.2x when compared with the non-concentrating solar PV cell.
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Mohanu, Alexandru Toma. "Moderni sistemi per il monitoraggio meteorologico e climatologico." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/21367/.
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La meteorologia studia le variazioni dei fenomeni atmosferici e ne raggruppa le informazioni in dati di temperatura, umidità, pressione, radiazione solare e vento. La climatologia studia i cambiamenti climatici a varie scale e per periodi di tempo non inferiori a 30 anni. L’aumento della potenza di calcolo, della quantità di dati e della qualità di raccolta delle informazioni meteorologiche ha permesso, negli ultimi 50 anni, un netto miglioramento dei modelli matematici climatici che sono diventati sempre più precisi nella descrizione del funzionamento dell’atmosfera terrestre. La tesi classifica gli strumenti moderni in base ai parametri meteorologici che osservano, e descrive la complessa rete di funzionamento che raccogliere informazioni sulle condizioni del pianeta dal suolo, dallo spazio e dagli oceani.
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Sholin, Veronica. "Luminescent solar concentrators and all-inorganic nanoparticle solar cells for solar energy harvesting /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2008. http://uclibs.org/PID/11984.
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Berryman, Ian. "Optimisation, design, development, and trial of a low-cost solar oven with novel concentrator geometry." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:42de9b33-18e1-4f22-8a44-3ddfd532bd0b.
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A promising and novel solar concentrator design has been thoroughly investigated and optimised. A prototype concentrator based on this novel geometry was validated using ray tracing techniques. This ray tracing demonstrated the comparative performance of this novel concentrator in regards to equivalent parabolic dishes. The effect of mirror surface normal errors on performance was established using Monte-Carlo based ray tracing code, which agreed well with the optical performance of this prototype which was determined experimentally. A need for low-cost solar cookers to replace bio-mass worldwide was identified, and the concentrator design was then developed as a low-cost solar oven. Despite existing in some number, no current design is able to achieve high performance at low-cost. An industrial partner, Dytecna, was initially involved in the process of this development of the system as a solar cooker. In support of a field trial for the solar cooker developed with Dytecna, a detailed thermal model of the oven was developed. A low-cost lightmeter was constructed and calibrated in order to measure the direct normal irradiance during the field trial in Italy. Laboratory work provided baseline results for the heating of various thermal masses in the oven. The Italian field trials provided a wealth of feedback into the design of the system and many valuable results. The solar cooker was able to bring 0.75L of water to the boil in 33 minutes with an average heat throughput of 203W. Important benchmark results and practical experience of several competing receiver materials was obtained; further lab testing provided more accurate measurements of the receivers' performances. The experiences of the Italian field trial were fed back into the design of a subsequent prototype, intended for a much larger field trial in Tanzania. Improvements in the hotplate, receiver material, and the oven were all incorporated into the design. Additionally, the structure of the solar cooker was redesigned to incorporate a low-cost wooden construction. Supporting work was conducted for the month long trial in which 8 solar cookers would be distributed to families in Tanzania. The field trial in Tanzania provided a wealth of user feedback into the design. At the same time the new solar cooker exceeded previously established performances in Italy. The new design was able to provide an average of 246W of heat to 1kg of water, which was brought to boiling point in 25 minutes. This represents a heating efficiency of 66% compared to the incident solar flux on the hotplate. In response to findings during the Tanzanian trials, further laboratory work was conducted into establishing the reflectivities of low-cost candidate mirror materials. Throughout all phases of the project the design of the solar cooker was refined and improved with the goal of a solar cooker design that could reach price-point, performance, and usability standards which would ensure market success.
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Schneider, Dirk. "Untersuchung von Methoden zur Früherkennung von Bränden in Wald- und Vegetationsgebieten." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-227018.
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Dissertation of Chief Fire Officer Dipl.-Ing. M. Sc. Dirk Schneider for achieving the academic degree of Dr.-Ing. of the Faculty of Forestry, Geo and Hydro Sciences of the Technical University of Dresden with the title: “Early Detection of Fires in Areas of Forests and other Vegetation”
Fires threaten and destroy extensive forest and vegetation areas every year, endangering people and its settlements, leading to significant pressures on the environment and destroying considerable high value resources. The expenditures in manpower, logistics and finance for safety in general and fire suppression in particular are considerable. To minimize these varied and extensive consequences of fires, early detection is desirable, making an effective firefighting strategy possible. This early detection is particularly of importance in remote, large-scale areas and territories not under observation by the population, especially if they are subject to an increased or high vulnerability. After investigating and considering the causes, that repeatedly lead to forest fires not only in the Federal Republic of Germany but worldwide, the author describes different traditional and modern methods for early detection of fires in areas of forests and other vegetation. Furthermore the author develops a performance item catalog, basing on practical and economic experience, by which not only novel early warning systems can be developed, but the systems and methods described in the present study also are assessed and compared. The comparison of various early warning systems is guided not only by means of technical features, but also from an economic perspective. Financial calculation methods, staff costs and the peculiarities in public administration are particularly noted. The author also shows the different parameters that influence the selection of an appropriate early warning system for the detection of forest and vegetation areas. It becomes clear that it is the scene of the incident with its specific parameters that determines the most useful early warning system.
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Grimley, W. K. "Bistatic sonar and a novel form of variable depth sonar : sonar systems research study." Thesis, Open University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296606.
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Reusswig, Philip David. "Sensitized energy transfer for organic solar cells, optical solar concentrators, and solar pumped lasers." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/93831.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 123-130).
The separation of chromophore absorption and excitonic processes, such as singlet exciton fission and photoluminescence, offers several advantages to the design of organic solar cells and luminescent solar concentrators (LSCs) for the end goal of achieving a lower cost solar energy generation. This thesis explores three new device architectures to overcome limited solar absorption in singlet-exciton-fission based solar cells and neodymium based LSCs. The process of singlet exciton fission is de-coupled from photon absorption, exciton diffusion, and charge transport in singlet-exciton-fission based solar cells by inserting a singlet fission material at the donor-acceptor interface of an organic solar cell. Singlet excitons generated in the singlet exciton donor are transferred to the singlet fission material through near field energy transfer. In this device structure, the singlet donor can be chosen for high photon absorption, exciton diffusion, and charge transport, and the singlet fission sensitizer can be selected for high singlet fission efficiency. We demonstrated a doubling of the external quantum efficiency from 12.8% to 27.6% in a singlet donor (TPTPA) through the introduction of thin film singlet fission sensitizer (rubrene) for high efficiency organic solar cells. To reduce the cost of electricity generated by sunlight via LSC systems, replacing the expensive high efficiency visible photovoltaic (PV) elements with cheap, high efficiency, earth abundant near-infrared PV elements made with silicon. This requires replacing within the LSC the visible emitting chromophores with near infrared emitters. Here, we present the use of a lanthanide ion, neodymium--colloidal nanocrystal energy cascade system as a promising LSC emitter scheme for the silicon spectral region. Peak optical quantum efficiencies of 43% in a Nd³+:glass based LSC are demonstrated with simulated high geometric gain performance. With cascade energy transfer, the optical quantum efficiency in the visible of a Nd³+:glass is significantly improved with peak efficiency of 28%. The enhanced solar absorption of Nd³+:glass through cascade energy transfer can be extended into the infrared with more optimal sensitizers. The idea of directly converting broad-band solar radiation into coherent and narrow-band laser radiation could enable many attractive technologies for solar energy. Here, we present an architecture for solar pumped lasers that uses a luminescent solar concentrator to decouple the conventional trade-off between solar absorption efficiency and the mode volume of the optical gain material. We report a 750-[mu]m-thick Nd³+-doped YAG planar waveguide sensitized by a luminescent CdSe/CdZnS (core/shell) colloidal nanocrystal, yielding a peak cascade energy transfer of 14%, a broad spectral response in the visible portion of the solar spectrum, and an equivalent quasi-CW solar lasing threshold of 20 W-cm2 , or approximately 200 suns. The efficient coupling of incoherent, spectrally broad sunlight in small gain volumes should allow the generation of coherent laser light from intensities of less than 100 suns.
by Philip David Reusswig.
Ph. D.
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Enshayan, Kamyar Short Ted H. "Measurement of solar radiation transmission in solar ponds /." Connect to resource, 1989. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1145375001.
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Parand, Foroutan. "Solar energy utilisation and evacuated tubular solar collectors." Thesis, Brunel University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292989.
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Enshayan, Kamyar. "Measurement of solar radiation transmission in solar ponds." The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu1145375001.
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Fallows, R. A. "Studies of solar wind throughout a solar cycle." Thesis, Aberystwyth University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.594095.
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Mahoney, Luther. "Solar hydrogen and solar electricity using mesoporous materials." Thesis, University of South Dakota, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3723927.
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The development of cost-effective materials for effective utilization of solar energy is a major challenge for solving the energy problems that face the world. This thesis work relates to the development of mesoporous materials for solar energy applications in the areas of photocatalytic water splitting and the generation of electricity. Mesoporous materials were employed throughout the studies because of their favorable physico-chemical properties such as high surface areas and large porosities. The first project was related to the use of a cubic periodic mesoporous material, MCM-48. The studies showed that chromium loading directly affected the phase of mesoporous silica formed. Furthermore, within the cubic MCM-48 structure, the loading of polychromate species determined the concentration of solar hydrogen produced. In an effort to determine the potential of mesoporous materials, titanium dioxide was prepared using the Evaporation-Induced Self-Assembly (EISA) synthetic method. The aging period directly determined the amount of various phases of titanium dioxide. This method was extended for the preparation of cobalt doped titanium dioxide for solar simulated hydrogen evolution. In another study, metal doped systems were synthesized using the EISA procedure and rhodamine B (RhB) dye sensitized and metal doped titania mesoporous materials were evaluated for visible light hydrogen evolution. The final study employed various mesoporous titanium dioxide materials for N719 dye sensitized solar cell (DSSC) materials for photovoltaic applications. The materials were extensively characterized using powder X-ray diffraction (XRD), nitrogen physisorption, diffuse reflectance spectroscopy (DRS), UV-Vis spectroscopy, Fourier-Transform-Infrared Spectroscopy (FT-IR), Raman spectroscopy, chemisorption, photoluminescence (PL), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). In addition, photoelectrochemical measurements were completed using current-voltage (I-V) curves, external quantum efficiency (EQE) curves, electrochemical impedance spectroscopy (EIS), and transient spectroscopy. The thesis work presented provides a better understanding of the role of mesoporous materials for solar hydrogen and solar electricity production.
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Contino, Alessandro Patrizio. "Solar mirrors characterization for concentrating solar power technology." Doctoral thesis, Università di Catania, 2012. http://hdl.handle.net/10761/993.
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The increasing availability on the market of different types of solar reflectors such as: polymeric film mirrors, aluminum mirrors and thin glass mirrors, together with: the lack of available norms in this area, and a valid methodology to compare the performances of the candidate reflectors; highlights the necessity to conduct a more detailed analysis on these new technologies.
The objective of the present work is to suggest a valuable method to compare the reflectance performance of mirrors, evaluating also their performances in order to assess:
- the most durable to ageing and weathering effects;
- the different reflectance behavior with the variation of the solar incident angle.
.For these reasons the work here proposed was carried out with an experimental apparatus composed by:
- An Agilent Cary 5000 UV/Vis/NIR spectrophotometer to test the different performance of the mirrors at different characterization steps;
- An integrating sphere of 150 mm in diameter (DRA ¡V Diffuse Reflectance Accessory);
- A VASRA (Variable Angle Specular Reflection Accessory);
- A UV chamber to accelerate the ageing process;
- A £gScan SMS Scatterometer for RMS Roughness and BDSF measurement;
- An outdoor bench
The work was completed with two modeling tools:
- An engineering equation solver (Mathcad) to dynamically evaluate the behavior;
- A ray tracing software (Soltrace) to evaluate the system¡¦s optical efficiency.
The analysis indicates that the candidate reflectors can be accurately characterized with five fundamental parameters:
a) £lSWH, the solar-weighted hemispherical reflectance;
b) £lSWS, the solar-weighted specular reflectance;
c) £lSWS( á), the solar weighted specular reflectance function of the variable angle of incidence;
d) BDSF, Bi Directional Scattering Function;
e) RMS Roughness
This evaluation will provide a valuable tool, for the companies who want to invest in concentrating solar power technology, to decide whether or not using a candidate reflectors to realize new plants, assessing their performances, their costs, and their durability.
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Bafana, Ramzi, and Zain Zulfiqar. "Solar Energy." Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2079.
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This thesis is about Photovoltaic (PV) cells and its stresses in various directions by calculating the power generated using solar cells under different conditions to improve its efficiency. Our research studies found that using multi-junction cells with larger substrates can increase the efficiency to some extent which in practice is limited to 43 percent. The experiment was conducted using ten solar cells each with an area of 20.9〖cm〗 ^2, where each cell gives 0.5 V and 0.4 A and a 1.25 Ω resistor was used. The cells were connected in series. Once, the PV cells were fixed horizontally and the other time tested in tilted position under same outdoor condition. The purpose of testing PV cells was to investigate the efficiency under above mentioned conditions. The data collected from the readings was used in calculation, and we have obtained from the calculations that horizontally fixed cells gave 4.8 percent efficiency whereas tilted cells gave 6.6 percent efficiency. Hence, the ratio showed that fixed cells produced 37.5 percent more power compared to horizontally fixed cells. Our other experiment consisted of testing PV cells under different temperature conditions that was done using a freezer and an oven for temperature variation and a tungsten bulb was used as a light source. The purpose of performing this experiment was to investigate how the efficiency of PV cells is affected under extreme conditions. Part of our thesis was also including studies and analysis of produced energy by the solar panel installed on the roof of “BTH” building in Karlskrona, Sweden. The data consisted of energy produced from February up to August 2014. The investigation also included finding the highest produced energy during these months. We have found that the highest energy was generated on the 1st of July which was 12.86 kWh. Furthermore, we went deep into investigation of the 1st of July to know exactly which hour of that day the highest energy was produced. The data showed that the highest produced energy was at 12:19 and 13:19 which was 2.03 kWh.Ramzi: +46723231353, +966561993488 Zain:
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Beltukov, Aleksei. "Sonar transforms /." Thesis, Connect to Dissertations & Theses @ Tufts University, 2004.
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Thesis (Ph.D.)--Tufts University, 2004.Adviser: Eric Todd Quinto. Submitted to the Dept. of Mathematics. Includes bibliographical references (leaves 282-290). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
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Serio, Ulises Daniel. "Energía solar." Bachelor's thesis, Universidad Nacional de Cuyo. Facultad de Ciencias Económicas, 2012. http://bdigital.uncu.edu.ar/5250.
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La energía solar posee un enorme potencial, por ejemplo, si un 10% del desierto de Sahara fuera instalado con paneles solares (suponiendo una efectividad de captación de radiación del 10%), produciría una cantidad de energía eléctrica equivalente al doble del consumo eléctrico mundial. De este modo no existe un problema de recursos o fuentes de energía, sino un problema de costos (actualmente, la energía solar es 10 veces más cara de producir que la provista por una central térmica tradicional) y las demás formas limpias de generar electricidad (hidroeléctrica, geotérmica, mareomotriz, eólica, etc.) no poseen la capacidad técnica de alimentar al planeta dado los recursos
limitados de las mismas (Lackner y Sachs 2005).
En Argentina el uso de este tipo de tecnología es todavía muy limitado. No obstante ha
aumentado recientemente la popularidad del uso de la energía solar (y calefones solares) en la región de Cuyo haciendo verdaderamente importante un estudio sobre si esta tendencia es correcta y conviene a la sociedad o si sus recursos serían mejor invertidos en otras tecnologías o gastos (incluso dentro del ámbito energético).
Un aspecto que resulta importante evaluar es la conveniencia de la implementación de estas tecnologías desde el punto de vista económico-privado ya que de esta manera se pueden direccionar acciones de políticas tendientes a incentivar el uso de las mismas.Fil: Serio, Ulises Daniel. Universidad Nacional de Cuyo. Facultad de Ciencias Económicas.
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Усенко, Наталія Миколаївна, Наталия Николаевна Усенко, Nataliia Mykolaivna Usenko, and I. V. Oliinyk. "Solar window." Thesis, Вид-во СумДУ, 2011. http://essuir.sumdu.edu.ua/handle/123456789/22075.
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In recent years various companies are developing technology to turn ordinary windows into solar panels. And now the U.S. firm New Energy Technologies has also decided to compete in the creation of new sources of energy generation, providing SolarWindow.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/22075
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Nawas, Yousef Ibrahim. "Solar House." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/9753.
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The Solar House is an investigation that resulted from an inter-disciplinary, design built competition ( the Solar Decathlon). This event was sponsored by the U.S. Department of Energy in an atempt to integrate architecture, technology, and dwelling.
The investigation focused on making a house using matter as a conduit to the spiritual, by emphasising two different natures in contrasting conditions. At the same time inclusive of all the technological aspects of a building that operates on solar energy, embedded with the complexities of building systems and new materials.Master of Architecture
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Elluru, Shailaja. "Solar vehicles." OpenSIUC, 2021. https://opensiuc.lib.siu.edu/theses/2824.
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Transportation-related greenhouse gas emissions are one of the most serious environmental concerns, and they are rising at an alarming pace. As a result, solar energy for transportation might be able to solve this problem. The aim of the proposed work is to contribute a technology that promotes Renewable energy; for example, imagine a situation in which we might use solar energy to charge electric cars that have solar panels-built in. solar powered vehicles that can collect and store solar power during their daily trips in their onboard solar batteries These cars can store some solar energy in the batteries and can run smoothly at night and also in the absence of sunlight. As vehicles return to their base stations, they move their Excess power collection to bigger base station batteries, which can be used later.
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Morini, Matteo. "Solar Wheel." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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L'elaborato tratta una particolare ruota solare prodotta da Marand, usata per le competizioni automobilistiche solari.
Dopo un'introduzione, che spiega chi è Marand, in cosa consiste la ruota a grandi linee e gli aspetti generali di cui tenere conto, segue una descrizione dei componenti principali che formano la ruota ed infine la procedura per smontarla/montarla.
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Marshall, Benjamin John. "Solar glider." Thesis, Marshall, Benjamin John (2012) Solar glider. Other thesis, Murdoch University, 2012. https://researchrepository.murdoch.edu.au/id/eprint/7459/.
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This report outlines the design and construction of a solar powered, radio controlled electric glider.
The design called for an electric glider that could take-off, climb and maintain continuous level flight during daylight hours on solar power alone in favourable atmospheric conditions.
The project required the successful completion of the following steps:
• Research and selection of a suitable airframe
• Selection of a propulsion system i.e. electric
motor, gearbox, propeller, and speed controller
• Selection of off-the-shelf radio transmitter, receiver, and servo actuators to control the glider from the ground
• Selection of a battery for energy storage
• The design of a solar array that can be integrated into the wing surface of the glider
• Research, design, construction and testing of a small, light and efficient maximum power point tracker (MPPT) based on a boost DC to DC converter.
The selection of the airframe used and the design and construction of the various sub-systems was aided by a mathematical model. This model was based on an energy balance and a weight balance of an aircraft in level flight.
The glider is now complete and testing has shown that the glider can fly on solar power alone in ideal atmospheric conditions. However these conditions do not exist very frequently in summer in Perth, Western Australia.
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Zomer, Clarissa Debiazi. "Megawatt Solar." reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/93727.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Civil, Florianópolis, 2010Made available in DSpace on 2012-10-25T02:45:18Z (GMT). No. of bitstreams: 1 279104.pdf: 12142340 bytes, checksum: ee36755aa6b85baae4cefb09fe871d54 (MD5)
A inserção de geradores convencionais de energia geralmente ocorre em locais afastados dos grandes centros urbanos, pois tende a acarretar problemas para o entorno como poluição do ar, poluição sonora e poluição visual. No entanto, com a energia cada vez mais necessária para o desenvolvimento humano, utilizar a fonte de geração próxima ao ponto de consumo é uma maneira eficaz de reduzir as perdas por transmissão e distribuição (T&D), Neste contexto, destaca-se a energia solar fotovoltaica, que, além de gerar eletricidade de forma distribuída, diferenciando-se da forma como se constitui o setor elétrico brasileiro, é inesgotável, silenciosa, estática, extremamente simples em sua operação, possui característica modular e pode integrar-se a edificações. Tem-se então, através da geração fotovoltaica, a oportunidade de instalar geradores limpos, renováveis e silenciosos em meio urbano. O objetivo desta dissertação é analisar a inserção do que poderia ser o maior gerador fotovoltaico da América do Sul de que se tem notícia até o presente, integrado ao envelope da edificação da Eletrosul, empresa do setor elétrico, localizada em área urbana de Florianópolis - SC. Através do estudo de área disponível na edificação e suas áreas adjacentes, quantificou-se o potencial fotovoltaico existente na Eletrosul. A partir daí, estimou-se a geração fotovoltaica horária, mensal e anual, a fim de comparar com o consumo da edificação. Com 1 MWp instalado, a contribuição anual seria de 31% do consumo energético, chegando a 42% no mês de dezembro. Na comparação horária, verificaram-se momentos de geração energética superior ao consumo, resultando em energia injetada na rede. Como o consumo e a geração fotovoltaica apresentaram curvas semelhantes, constatou-se a possibilidade de uma recontratação de demanda pela empresa, agregando mais valor à integração fotovoltaica. Por fim, analisou-se a participação da geração deste sistema de grande porte na redução de consumo energético no alimentador em que a edificação está inserida. Neste caso, a contribuição foi de 5% do consumo anual. Através das análises, pode-se quantificar a contribuição energética de um gerador fotovoltaico de grande porte tanto para a edificação quanto para o alimentador em que ela está inserida.
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Invidiata, Andrea. "Solar Decathlon." reponame:Repositório Institucional da UFSC, 2013. https://repositorio.ufsc.br/handle/123456789/106838.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-graduação em Arquitetura e Urbanismo, Florianópolis, 2013.Made available in DSpace on 2013-12-05T22:31:27Z (GMT). No. of bitstreams: 1 321418.pdf: 52040815 bytes, checksum: bfd73e577ec371789136ebb5f371b7ab (MD5) Previous issue date: 2013
O progresso e a pesquisa para tornar os edifícios mais eficientes e, ao mesmo tempo, mais confortáveis, vêm sendo o foco do novo conceito de arquitetura. Um exemplo de como essa evolução está sendo concretizada é o Solar Dechatlon, uma competição (criada em 2002) entre universidades do mundo todo que projetam e constroem casas autossuficientes energeticamente, pois operam utilizando apenas energia solar. A competição visa a construção de casas extremamente eficientes, avaliadas em diferentes quesitos, dentre os quais está a eficiência energética. Em setembro de 2012, foi sediada em Madri e na Espanha, contando pela primeira vez com uma equipe brasileira, representada pela Ekó House. O projeto da Ekó House foi realizado considerando as condições climáticas de Madri, no mês de setembro, para conseguir o melhor desempenho possível da casa durante a competição. A casa, no panorama brasileiro, não apresenta a mesma eficiência que na cidade da competição, com um balanço energético final que só as cidades de Brasília, Montes Claros e Goiânia têm um resultado parecido com a cidade de Madri. Esta pesquisa de Mestrado, portanto, tem o objetivo de avaliar a casa nas diferentes zonas bioclimáticas brasileiras por meio de três metodologias distintas (balanço energético, RTQ-R prescritivo e RTQ-R simulação) e propor, para cada região, um modelo adaptado às condições das diferentes cidades brasileiras analisadas. O objetivo da pesquisa é reutilizar o projeto Ekó House no Brasil da maneira mais eficiente para as condições climáticas do país, e, ao mesmo tempo, criar uma referência projetual para futuras participações na competição Solar Decathlon, tendo como foco, além da competição, a aplicação da casa no território brasileiro. A revisão bibliográfica é centrada em um melhor conhecimento da competição Solar Decathlon e da casa brasileira, abordando também os temas de arquitetura bioclimática e da eficiência energética nas edificações, tendo como foco o uso de tecnologias de energia solar. Por fim, uma análise das normas brasileiras relacionadas à eficiência energética nas edificações concluirá a revisão bibliográfica. A metodologia, por sua vez, é baseada na análise quantitativa da casa na cidade da competição e nas cidades brasileiras escolhidas. A avaliação da eficiência energética da casa será feita por meio de três métodos de análise diferentes: balanço energético, método prescritivo do RTQ-R e método de simulação do RTQ-R. Por último, a casa será alterada nas diferentes regiões, de acordo com as entrevistas feitas com os membros da equipe, com as normas brasileiras e de análise climática das cidades ! onde a casa será avaliada. Dessa forma, será obtido para cada cidade um modelo de casa Ekó House mais eficiente. Os resultados finais demonstram que a casa obteve um melhor desempenho energético por meio das alterações de projeto propostas em todas as cidades brasileiras. As cidades com condições climáticas mais quentes apresentaram um maior benefício das alterações de projeto aportadas, reduzindo o consumo em até 20% comparado com o projeto original da casa
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Karlsson, Jimmy. "Solar tracker." Thesis, Uppsala universitet, Signaler och System, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-387629.
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We are facing a climate crisis, and the world needs to generate electricity in more climate neutral ways. One alternative is to use solar energy. The highest efficiency can be achieved if the surface normal is pointed towards the sun, instead of just having it stationary. To solve this, people make a system called a solar tracker. In this project a prototype of a solar tracker is made, which can follow the sun in any direction. The solar tracker consists of a mechanical structure, two DC-motors that move the structure, and a microcontroller that implements the regulator to control the motors. All the mechanical parts were constructed and then printed using a 3D-printer. Manual control was implemented for making troubleshooting and testing easier. The electrical system is soldered on an experimental board and then mounted with the motor driver and mechanical construction on a bottom structure. There are a few interesting things that could be further developed. One is to implement sensors at the start point and end point of the sun tracking so that the tracker can return to the starting point after the sunset. It would be interesting to scale up the construction a bit and make some more useful measurements on larger panels to see if the system is energy effective enough to be useful; to make some outdoor tests and see how the sensors and control system work in a real-world environment; and to investigate and eventually develop its ability to adapt to cloudy weather.