Dissertations / Theses: 'Insolation'

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Heisterkamp, Norbert. "Flächendeckende Erfassung und Beschreibung der solaren Strahlung zum Zweck einer kurzfristigen und räumlich kleinskaligen Einstrahlungsprognose /." Düsseldorf : VDI-Verl, 1999. http://www.gbv.de/dms/bs/toc/266403131.pdf.

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Raja, Iftikhar Ahmed. "Solar radiation assessment in Pakistan." Thesis, University of Strathclyde, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343245.

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Lederach, Stephen A. "Insolation transmission through a deciduous tree canopy: a winter study." Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/51905.

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This study measures the shading properties of tree branches as they affect the amount of available sunlight (insolation) reaching structures placed within the visible tree shadow. Measurement was accomplished by placing a grid in throughout the entire shadow pattern formed, by each study tree between the hours of 9:00 am and 3:00 pm. Data was collected at each point of the grid to determine the percent insolation blockage or penetration, through a tree canopy. This data was then transferred to a graphed tree shadow pattern and interpolated to create tree shading density contours in the tree shadow pattern. Data was analyzed to determine the effects of sample tree shadow patterns upon the passive solar heat gain of windows located within the tree shadow. This study offers as a guide to future research, the beginning of a tree typology. The typology categories trees commonly grown and available in Virginia, into form and size categories. The typology also begins to assimilate data collected by other researchers on summer and winter canopy densities, leaf drop, and leaf onset periods. The typology creates a framework for future research and serves as a means to record which trees have been investigated, and which have not. Another attribute of the typology is its potential benefit to designers. It can be utilized as a tree selection tool for energy-conserving landscape designs. Several additional questions and suggested improvements for data collection have been provided for those who care to continue research into this area. Master of Landscape Architecture

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Prakhova, Sofya. "A new approach for modelling insolation from the space perspective." Thesis, Curtin University, 2014. http://hdl.handle.net/20.500.11937/1327.

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In this thesis we present a new approach for modelling insolation from the space perspective. The incoming radiation was modelled as a flux passing through a cross-section (latitudinal belt), and the changes of light throughout the year were represented by an ellipse with changing parameters. The modelling approach used allows the incorporation of the impact of space activity (such as solar flares, galactic radiation and so on) on the Earth’s climate.

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Klopfer, Scott D. "Insolation, Precipitation, and Moisture Maps for a Virginia Geographic Information System." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36915.

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Climate information is valuable in understanding the ecology of systems affecting wildlife. This information is often unavailable at the landscape scale. This study evaluated the applicability of several climate factor estimates at the landscape-scale, and illustrated the usefulness of estimated climate factors in ecological investigations. Climate variables estimated for each month of the year were solar radiation, temperature, precipitation, and potential evapotranspiration. Map layers for combined temperature and precipitation, and a moisture index were also created. Accuracy of the estimates for temperature and precipitation for each 300 m x 300 m pixel were quantitatively assessed. The methods used estimated mean monthly temperature within 1 degree C. Precipitation estimates were within 9 mm of actual recorded value. The estimates for monthly solar radiation were qualitatively assessed, and provided a reasonable relative index to actual solar radiation. Estimates of potential evapotranspiration were determined to be reasonably accurate. Landscape-scale estimated climate factors were used in 2 case studies. The first used logistic regression to examine the importance of climate factors to the observed distribution of 21 select forest cover-types in Virginia.The second compared the observed climate characteristics for the distributions of 3 species of terrestrial salamanders in Virginia. Winter temperature was the most important climate variable in determining forest cover-type distribution. Several differences in the climate characteristics of the 3 salamander distributions were observed and discussed. The conclusions of this study were that landscape-scale climate factors can be accurately estimated, and the estimates may be helpful in ecological investigations. Master of Science

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Wolete, Joseph N. "An Interactive Menu-Driven Design Tool For Stand-Alone Photovoltaic Systems." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/35878.

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The use of Photovoltaic (PV) systems to meet energy demand in rural or remote regions of the world is growing at a very fast pace. Rural electrification projects in developing countries have relied primarily on subsidies from both the government and the national utility. Since using the national grid to meet energy demand in these areas has been found to be quite expensive over time, governments in developing countries have turned to photovoltaic technology as a means of providing electricity needs to their rural population. To facilitate the use of PV systems in developing countries, the author has developed an interactive menu-driven design tool called PVONE that may serve as a guide to engineers and government officials to decide whether a stand-alone photovoltaic system is feasible at a location. PVONE consists of three parts - insolation, system design and economic analysis. In order to predict insolation, PVONE first utilizes the clear sky insolation model that is based on latitude, longitude and altitude of a location. Then it incorporates the standard classification criteria to classify the days of a month according to day types. Based on how the days are classified, a new set of insolation is predicted. For system design, the PVONE program is used to determine the array characteristics based on the chosen photovoltaic module, the system design load and the daily insolation at the location. To determine whether the proposed system is feasible at the location, the PVONE program performs an energy output analysis and economic analysis. The system designed is considered feasible at the location only if it satisfies the load demand and has a positive net present value. Master of Science

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Arrell, Russell 1975. "Implications of Martian polar insolation levels on the climatic cycling of volatiles." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/53045.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2000. Includes bibliographical references (leaves 35-36). Solar insolation at the poles is the driving force in Mars' seasonal climatic cycle. Mars' obliquity has varied greatly in the geologically recent past and this would have had a profound effect on the past climate. Previous studies have always assumed a spherical planet when calculating insolation. This study uses a geodetic elevation model (GEM) of the elevation data from the Mars Orbiter Laser Altimeter, to provide accurate insolation calculations. This method takes into account the long and shortwavelength topography, the planetary curvature, and the planetary flattening. This paper outlines the design and implementation of a GEM, and presents insolation calculations for Mar's north polar cap for obliquities of 150, 250 and 450. This study found that the elevation of the northern ice cap above the surroundings results in the ice cap having more days of sunlight than previously thought. by Russell Arrell. S.M.

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Butler, Kirt Gordon. "Relationship of Solar Energy Installation Permits to Renewable Portfolio Standards and Insolation." Thesis, Walden University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3739574.

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Legislated renewable portfolio standards (RPSs) may not be the key to ensure forecast energy demands are met. States without a legislated RPS and with efficient permitting procedures were found to have approved and issued 28.57% more permits on average than those with a legislated RPS. Assessment models to make informed decisions about the need and effect of legislated RPSs do not exist. Decision makers and policy creators need to use empirical data and a viable model to resolve the debate over a nationally legislated RPS. The purpose of this cross-sectional study was to determine if relationships between the independent variables of RPS and insolation levels and the dependent variable of the percentage of permits approved would prove to be a viable model. The research population was 68 cities in the United States, of which 55 were used in this study. The return on investment economic decision model provided the theoretical framework for this study and the model generated. The output of multiple regression analysis indicated a weak to medium positive relationship among the variables. None of these relationships were statistically significant at the 0.05 level. A model using site specific data might yield significant results and be useful for determining which solar energy projects to pursue and where to implement them without Federal or State mandated RPSs. A viable model would bring about efficiency gains in the permitting process and effectiveness gains in promoting installations of solar energy-based systems. Research leading to the development of a viable model would benefit society by encouraging the development of sustainable energy sources and helping to meet forecast energy demands.

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Curran, Lorna L. "Examining the Role of Latitude and Differential Insolation in Asymmetrical Valley Development." Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc283821/.

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Valley development through erosional processes typically tends to create symmetrical valleys. Over time, water cuts through the substrate to create valleys, gorges, and canyons for which the sides are the valley are evenly sloped. However, there are anomalies to this process. Asymmetrical valleys have been well-documented even in areas of uniform substrate or little tectonic uplift. One proposed explanation for the asymmetry of these valleys is differential insolation. This may lead to different microclimates from one slope to another which alter the rate and extent of erosion. Since the differences in received insolation vary with latitude (especially in streams that flow along an east/west axis), it follows that the degree of asymmetry should also vary with latitude if differential insolation is a primary driving factor in the development of these valleys. To evaluate if insolation plays a role in the development of asymmetrical valleys, this study examines variability in asymmetry across 447 valleys in nine study areas located at different latitudes. The degree of asymmetry for each valley was measured by using 30 meter resolution digital elevation models (DEMs) to determine the slope angle of each side of the valley. Asymmetry was measured by computing a ratio of the average slope angle for each side of the valley (larger value divided by smaller). If the resulting value is one, the valley is deemed symmetrical. As the value increases, the degree of asymmetry increases. This investigation found that contrary to expectations, valleys at lower latitudes tend to have a higher degree of asymmetry than those at higher latitudes, which suggests that differential insolation does not play a major role in the development of these valleys. Instead, this study found that high altitudes and low latitudes are more frequently associated with a higher degree of asymmetry. These unexpected findings open the door to new avenues of investigation into the causes of asymmetrical valley development.

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Moores, John Edward. "Effects of Insolation on Habitability and the Isotopic History of Martian Water." Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/194111.

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Three aspects of the Habitability of the Northern Plains of Mars to organics and terrestrial-like microbial life were assessed. (1) Protection offered by small surface features and (2) the breakdown of rocks to form soils were examined using a radiative transfer computer model. Two separate sublimation experiments provided a basis to improve (3) estimates of the amount of available water today and in the past by determining the fractionation of HDO between present-day reservoirs.(1) UV radiation sterilizes the hardiest of terrestrial organisms within minutes on the Martian surface. Small surface features including pits, trenches, flat faces and overhangs may create "safe havens" for organisms by blocking much of the UV flux. In the most favorable cases, this flux is sufficiently reduced such that organic in-fall could accumulate beneath overhanging surfaces and in pits and cracks while terrestrial microorganisms could persist for several tens of martian years.(2) The production of soils on the surface is considered by analogy with the arid US Southwest. Here differential insolation of incipient cracks of random orientations predicts crack orientation distributions consistent with field observations by assuming that only crack orientations which shield their interiors, minimizing their water loss, can grow, eventually disrupting the clast.(3) Disaggregated water ice to simulate the polar caps was produced by flash freezing in liquid nitrogen and crushing. When dust was added to the mixtures, the D/H ratio of the sublimate gas was seen to decrease with time from the bulk ratio. The more dust was added to the mixture, the more pronounced was this effect. The largest fractionation factor observed during these experiments was 2.5. Clean ice was also prepared and overlain by dust to simulate ground ice. Here, the movement of water vapor was modeled using an effective diffusivity that incorporated both adsorption on grains and diffusion. For low temperatures (<-55Â°C) a significant difference between the diffusivities of H2O and HDO was observed. This suggests adsorptive-control within the regolith as energies of interaction are 60-70kJmol-1. This ability of the martian regolith to preferentially adsorb HDO decouples the ice table and polar caps from the atmosphere and allows for geographic variations in the D/H ratio on Mars.

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Thomson, Susan C. "Why do bats fly at night? : the role of hyperthermia in constraining diurnal flight in bats." Thesis, University of Aberdeen, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323141.

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Askar, H. K. "Developing a multiple glazing system to minimize transmission of direct insolation for particular latitudes." Thesis, Cranfield University, 2006. http://hdl.handle.net/1826/4029.

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Too often, in the last 50 years, the energy-thrift lessons of vernacular architecture have been forgotten or ignored. In the Middle East, many recently-designed commercial buildings, with large areas of glazing, incur excessively high electricity-demands to provide energy for the required air-conditioning plant. One way of reducing the magnitude of this demand is through better window design. A new glazing system is proposed that utilizes the insertion of a clear glazing element within the cavity of a double glazed window. The main objective of this system is to achieve acceptable levels of daylight within a building by attempting to maintain the diffuse component of insolation while reducing the penetration of direct component by using the increased reflectivity of these materials with the angle of incidence of the direct beam component of solar irradiation. By using clear glazing materials the proposed system attempts to achieve acceptable performance without the need for elaborate and expensive coatings or substrates. Because solar geometry varies with latitude a varying performance of glazing systems is expected with current glazing systems. However, the suggested system utilizes an optimal angle for overall daylighting and thermal performance that relates to the particular solar geometry of interest, New software is also developed to assess the performance of the suggested system; this involved examining all the modes of heat transfer through the entire glazing system. Results then were assessed to calculate the optimal angle of the element that corresponds to the solar geometry of particular latitude. Such proposal takes a new perspective, once it is acknowledged that though different forms of advanced glazing systems currently are being used to inhibit the penetration of direct solar radiation, still the main disadvantages of such advanced glazing systems are that they are relatively expensive and would reduce the penetration of a considerable part of the daylight entering the space.

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Benchimol, Nicole. "The mesoscale variability of insolation over the Lower Fraser Valley resolved by geostationary satellite data." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/24477.

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Assessments of the mesoscale variability of the insolation over the lower Fraser Valley have been hampered by the inadequate spatial resolution of the available pyranometric data. At present, the establishment of a dense ground-based observing network is economically infeasible. The adaptation of geostationary satellite data for estimating insolation is an attractive alternative. The ability of a simple physically-based model (Gautier et al., 1980) to resolve the hourly mesoscale insolation variability is evaluated. The satellite-based estimates are shown to be more coherent than the observed insolation. Discrepancies are attributed to the spatial averaging inherent in the satellite methodology. The estimates are found to be insensitive to spatial averaging down to a 3 x 3 pixel (about 13 km₂ ) scale. The effects of spatial averaging are believed to occur at smaller spatial scales. The satellite-based estimates generally display a good correspondence with the observed insolation. Maps of the mean hourly estimated insolation are obtained with a high degree of accuracy due to small systematic modelling errors. The inability of the model to distinguish between snow and cloud, and its sensitivity to variations in surface albedo introduce artifacts in maps of the clear sky insolation. On the other hand, the mesoscale variability of individual hourly fields cannot be resolved using 'the satellite-based approach. Errors for these estimates are so large that they obscure the variability of the insolation field. The usefulness of the mapping procedure appears to be limited to assessments of the average insolation. Arts, Faculty of Geography, Department of Graduate

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Huybers, Peter 1974. "On the origins of the ice ages : insolation forcing, age models, and nonlinear climate change." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/88360.

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Thesis (Sc. D. in Climate Physics and Chemistry)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2004. Includes bibliographical references (p. 229-245). This thesis revolves about the relationship between orbital forcing and climate variability. To place paleo and modern climate variability in context, the spectrum of temperature variability is estimated from time-scales of months to hundreds of thou- sands of years using a patchwork of proxy and instrumental records. There is an energetic background continuum and rich spatial structure associated with temperature variability which both scale according to simple spectral power-laws. To complement the spatial and temporal analysis of temperature variability, a description of the full insolation forcing is also developed using Legendre polynomials to represent the spatial modes of variability and singular vectors to represent seasonal and long-term changes. The leading four spatial and temporal modes describe over 99% of the insolation variability making this a relatively simple and compact description of the full insolation forcing. Particular attention is paid to the insolation variations resulting from the precession of the equinoxes. There is no mean annual insolation variability associated with precession - precession only modulates the seasonal cycle. Nonlinear rectification of the seasonal cycle generates precession-period variability, and such rectification naturally occurs in the climate system but also results from the seasonality inherent to many climate proxies. One must distinguish this latter instrumental effect from true climate responses. Another potential source of spurious low-frequency variability results from the stretching and squeezing of an age-model so that noise in a record is made to align with an orbital signal. (cont.) Furthermore, and contrary to assertions made elsewhere, such orbital-tuning can also generate an eccentricity-like amplitude modulation in records that have been narrow-band-pass filtered over the precession bands. An accurate age-model is the linchpin required to connect insolation forcing with any resulting climatic responses, and to avoid circular reasoning, this age-model should make no orbital assumptions. A new chronology of glaciation, spanning the last 780 kilo-years, is estimated from 21 marine sediment cores using a compaction corrected depth scale as a proxy for time. Age-model uncertainty estimates are made using a stochastic model of marine sediment accumulation. The depth-derived ages are estimated to be accurate to within L9, 000 years, and within this uncertainty are consistent with the orbitally-tuned age estimates. Nonetheless, the remaining differences between the depth and orbitally derived chronologies produce important differences in the spectral domain. From the 6180 record, using the depth-derived ages, evidence is found for a nonlinear coupling involving the 100KY and obliquity frequency bands which generates interaction bands at sum and difference frequencies. If an orbitally-tuned age-model is instead applied, these interactions are suppressed, with the system appearing more nearly linear. A generalized phase synchronization analysis is used to further assess the nonlinear coupling between obliquity and the glacial cycles. Using a formal hypothesis testing procedure, it is shown that glacial terminations are associated with high obliquity states at the 95% significance level. The association of terminations with eccentricity or precession is indistinguishable from chance. (cont.) A simple excitable system is introduced to explore potential mechanisms by which obliquity paces the glacial cycles. After tuning a small number of adjustable parameters, the excitable model repro- duces the correct timing for each termination as well as the linear and nonlinear features earlier identified in the 6180 record. Under a wide range of conditions the model exhibits a chaotic amplitude response to insolation forcing. One chaotic mode gives a train of small and nearly equal amplitude 40KY cycles. Another mode permits ice to accumulate over two (80KY) or three obliquity cycles (120KY) prior to rapidly ablating and thus, on average, generates 100KY variability. The model spontaneously switches between these 40 and 100KY chaotic modes, suggesting that the Mid-Pleistocene Transition may be independent of any major shifts in the background state of the climate system. by Peter Huybers. Sc.D.in Climate Physics and Chemistry

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Buie, Damien Charles William. "Optical considerations in solar concentrating systems." Thesis, The University of Sydney, 2003. http://hdl.handle.net/2123/587.

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To optimise the performance of concentrating solar power systems, a detailed knowledge of the resultant flux distribution in the imaging plane is required. To achieve this, an accurate model of the direct solar beam impinging on the concentrator is essential. This thesis presents an empirical model of the terrestrial solar distribution that has both a high-correlation to observed data and an invariance to a change in location. The model is based on the amount of circumsolar radiation in the direct beam and takes into account the small variations that are due to atmospheric scattering. A modelling framework is developed to simulate the flux distribution in the imaging plane of a generic solar concentrating system. Algorithms are developed to include the following: the spatial solar energy distribution; the systemic effect of reflecting that distribution off a non-ideal mirrored surface; the spectral energy distribution; the transmission, absorption and reflection characteristics of optical thin films; and the coordinates of the solar vector. The framework is then used to investigate the performance of anti-reflection coatings on silicon substrates and the performance of linear Fresnel systems. Combined, these algorithms and simulation tools can be applied to create comprehensive optical models of solar concentrating systems.

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Lundström, Hannah, and Emil Hagström. "A field study in Kenya of insolation parameters to make water drinkable in the household water treatment unit SOLVATTEN." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-176986.

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SOLVATTEN is a household water cleaning device that cleans water with solar energy using filtration, pasteurization and UV sterilization. A field study of the necessary amount of solar insolation that is required to make water drinkable has been carried out in Kenya using a new type of indicator developed by Solvatten AB. This new indicator will complement the old one, which only registers the temperature, with new features to store information about temperature and insolation. The indicators have been calibrated for energy and temperature and a Matlab program has been developed to analyze the information registered by the indicators. The program handles the time shifting that occurs since the indicator only saves the data at some point during a quarter of an hour. It also handles temperature correction and does a suitable curve fitting using polyfit and spline. The experiments have been divided into two parts, one where the relationship between UV and total solar insolation has been studied and one where we have taken water samples and studied the limiting factors of temperature, UV and total insolation for drinkable water. Previous studies have showed that the water in SOLVATTEN gets clean at 55 C. To reach this temperature the required UV245-400 and UV190-570 insolation is 83.0 Wh/m2 and 307 Wh/m2 according to our tests. The required total insolation is 2680 Wh/m2. From our measurement it can be seen that it is possible for water to be clean at 53 °C. During our artificial tests where we pre-heated the water and thus decreased the total insolation, we never got below 8.2 Wh/indicator which correspond to 1940 Wh/m2 of total insolation at 55 °C. The limit for clean water shown from earlier tests by Solvatten AB is 8 Wh/indicator. Even when the temperature was lower than 55 °C and we got clean water, the insolation was never below this value. This means that it is the temperature that is the limiting factor; however the synergy effect with the insolation is essential for the cleaning process. When it is cloudy the amount of UV that SOLVATTEN receives will be lower compared to the total insolation. With more clouds the temperature will drop and rise many times, while the insolation continues to increase. This means that more clouds will give more total insolation. The shortest time it took to reach 55 °C was 1 hours and 45 minutes at an optimal angle to the sun. SOLVATTEN är en vattenreningslösning för hushåll som kombinerar filtrering, uppvärmning samt UV-strålning för att döda bakterier. Det är en 11 liters plastdunk, där ena sidan är genomskinlig, och efter att den har exponerats i solen mellan 2- 6 timmar är vattnet rent. En fältstudie har genomförts i Kenya för att undersöka exakt hur mycket solinstrålning som krävs för att vattnet ska bli rent. Idag finns det en väl fungerande indikator som mäter vattnets temperatur men en ny indikator har tagits fram av Solvatten AB som även mäter solinstrålningen och kan lagra den tillsammans med vattentemperaturen. Indikatorerna har kalibrerats för att få rätt energi och temperatur och ett Matlab-program har utvecklats för att kunna analysera informationen. För att kunna ta fram exakta värden används funktionerna polyfit och spline för att kurvanpassa datan. Programmet tar även hänsyn och korrigerar för de fel som kan uppkomma då tiden sparas. Dessa tidsfel uppkommer då indikatorerna endast skriver informationen någon gång under en kvart. Fältstudien är uppdelad i två delar, en där relationen mellan UV och total instrålning har studerats och en där vattenprover har tagits för att undersöka vilken som är den begränsande faktorn för rent vatten; temperatur, UV eller total instrålning. Tidigare studier har visat att SOLVATTEN blir rent vid 55 C. För att lyckas uppnå denna temperatur har det i vår studie krävts 83.0 Wh/m2 av UV245-400 och 307 Wh/m2 av UV190-570. När det gäller den totala instrålningen har det behövts 2680 Wh/m2. Vi har sett att det är möjligt för vattnet att bli rent vid 53 °C. Under våra tester då vi förvärmde vattnet och på sätt fick mindre instrålning, lyckades vi aldrig få under 8.2 Wh/indikator vilket motsvarar 1940 Wh/m2 av totala instrålningen, detta vid 55 °C. Tidigare tester av Solvatten AB visar att det behövs 8 Wh/indikator för att uppnå rent vatten och då vi aldrig lyckades få in mindre instrålning än så tyder det på att det är temperaturen som är den begränsande faktorn. Dock är instrålningen nödvändig då det är synergieffekten mellan värme och instrålningen som uppnår rent vatten vid så låga temperaturer. Om det är mycket moln på himlen sjunker och ökar temperaturen många gånger medan solinstrålningen fortsätter att ackumuleras. Detta betyder att den instrålade energin som når SOLVATTEN blir högre då det krävs längre exponeringstid för att nå 55 °C. Dock har vi sett att mängden UV inte ökar lika mycket som den totala instrålningen men ett generellt förhållande av hur UV och total instrålning förändras vid molnigt väder är dock svårt att kunna få fram. Den kortaste tiden för att uppnå rent vatten är 1 timme och 45 minuter då SOLVATTEN har haft en optimal vinkel mot solen.

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Leconte, Bruno. "Contribution à l'étude de la photosensibilité des fibres en silice sous l'effet d'une insolation par un laser à ArF." Lille 1, 1998. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/1998/50376-1998-397.pdf.

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Ce memoire traite de la photosensibilite de fibres optiques en silice sous l'effet d'insolations realisees a l'aide d'un laser a arf. La realisation de l'etude a necessite la mise en place d'un nouveau dispositif d'inscription de reseaux de bragg. Les variations d'indice de refraction photoinduites dans les fibres optiques sont estimees en mesurant les caracteristiques spectrales de reseaux de bragg photoinscrits. Nous presentons une etude detaillee des conditions d'utilisation de ce dispositif. Nous discutons des hypotheses usuellement formulees lors de l'exploitation de la mesure des caracteristiques spectrales des reseaux de bragg. La seconde partie du memoire porte sur la photosensibilite de fibres dont le cur est dope par de l'oxyde de germanium. Nous montrons que les inscriptions de reseaux de bragg sont plus rapides lorsque #p = 193 nm que lorsque #p 244 nm. Cependant, lors de l'utilisation du laser a arf, l'insolation conduit frequemment a des cinetiques de croissances de reseaux de type iia. L'etude des mecanismes microscopiques mis en jeux lors des insolations uv nous a amene a proposer une methode originale d'utilisation du modele de kramers-kronig. L'insolation d'une fibre en silice par un rayonnement ultraviolet peut se traduire par differents effets indesirables. L'etude de la photosensibilite de fibres aluminosilicates dopees par des ions erbium a permis de mettre en evidence le caractere penalisant pour la realisation de lasers a fibres, des insolations realisees sur des fibres prealablement hydrogenees. Par ailleurs, nous avons etudie la photosensibilite d'un type de fibres en silice a cur dope par de l'azote. Il a ete possible d'induire des variations d'indice de refraction superieures a 110##3. Ces variations d'indice de refraction photoinduites sont extremement resistantes a l'elevation de temperature et aux radiations gamma.

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Attia, Rabah. "Couplage par réseau de Bragg entre microguides optiques se croisant à angle droit." Valenciennes, 1986. https://ged.uphf.fr/nuxeo/site/esupversions/5052cbd3-9faa-4589-b713-08155b1f411c.

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Couplage par déflexion de Bragg provoquée par un réseau en couche mince disposé à leur intersection. Divergence d'un faisceau guidé lorsqu'il quitte un microguide pour pénétrer dans un guide plan. Techniques de fabrication des guides et des réseaux. Transfert de puissance. Rôle de la polarisation des modes incidents et diffractes. Valeurs maximes des différents taux de couplage intermodaux. Influence de l'orientation du réseau confirmée expérimentalement avec des composants en verre échangé.

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Razafimahatratra, Dominique. "Etude de la stabilité de la variation d'indice de réfraction photoinduite par insolation laser dans les guides d'ondes optiques germanosilicates." Lille 1, 2000. https://pepite-depot.univ-lille.fr/RESTREINT/Th_Num/2000/50376-2000-145.pdf.

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La photosensibilite d'un verre (verre massif, fibre ou guide planaire) peut etre definie de facon macroscopique comme une modification de la transmission spectrale et de l'indice de refraction du materiau soumis a une irradiation. L'insolation appropriee (en longueur d'onde, en forme et en intensite) de guides optiques permet de realiser des composants a reseaux de bragg utilises dans le domaine des capteurs et des telecommunications. Dans ce memoire, la stabilite thermique des reseaux de bragg photoinscrits dans les fibres optiques et guides d'onde planaires germanosilicates est etudiee afin de valider des modeles predictifs du vieillissement de ces composants. Ces reseaux ont ete inscrits avec un laser ultraviolet fonctionnant en regime pulse ou en regime continu. Deux methodes ont ete utilisees afin d'etudier la stabilite thermique des reseaux de bragg photoinscrits dans les fibres germanosilicates codopees avec du bore et de l'etain. La methode isochrone consiste a chauffer les reseaux pendant une periode fixe t en faisant varier la temperature t par palier de 50\c. La seconde methode appelee isotherme consiste a chauffer a temperature fixe t en chauffage a permis de valider le concept de l'energie de demarcation e d. Une etude de stabilite thermique des reseaux de bragg inscrits dans des fibres germanosilicates codopees avec du bore ou de l'etain a ete realisee sur une periode de trois ans en utilisant la methode isotherme Les reseaux inscrits dans les fibres hydrogenees montrent une stabilite thermique inferieure a ceux inscrits dans les fibres non chargees en hydrogene. L'utilisation du bore comme codopant degrade fortement la tenue thermique des reseaux de bragg. Les reseaux de type iia presentent une stabilite thermique largement superieure aux reseaux de type i. Dans la deuxieme partie de ce travail, nous nous sommes propose d'etudier la photosensibilite et la stabilite des reseaux de bragg realises dans les films germanosilicates elabores par voie sol-gel. L'hydrogenation de ces guides a ete necessaire afin d'ameliorer leur photosensibilite. Des etudes de la surface insolee a l'aide de microscope a forces atomiques et du profilometre ont ete effectuees pour mieux comprendre les mecanismes a l'origine de la photosensibilite de ces guides. L'etude de la stabilite thermique des reseaux a ete realisee en utilisant la methode isochrone. Nous avons pu en deduire une estimation de l'amplitude de la variation d'indice photoinduite de l'ordre de 10 3 et les valeurs obtenues sont en accord avec les resultats obtenus dans les verres germanosilicates

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Buie, Damien Charles William. "Optical considerations in solar concentrating systems." University of Sydney. Physics, 2004. http://hdl.handle.net/2123/587.

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To optimise the performance of concentrating solar power systems, a detailed knowledge of the resultant flux distribution in the imaging plane is required. To achieve this, an accurate model of the direct solar beam impinging on the concentrator is essential. This thesis presents an empirical model of the terrestrial solar distribution that has both a high-correlation to observed data and an invariance to a change in location. The model is based on the amount of circumsolar radiation in the direct beam and takes into account the small variations that are due to atmospheric scattering. A modelling framework is developed to simulate the flux distribution in the imaging plane of a generic solar concentrating system. Algorithms are developed to include the following: the spatial solar energy distribution; the systemic effect of reflecting that distribution off a non-ideal mirrored surface; the spectral energy distribution; the transmission, absorption and reflection characteristics of optical thin films; and the coordinates of the solar vector. The framework is then used to investigate the performance of anti-reflection coatings on silicon substrates and the performance of linear Fresnel systems. Combined, these algorithms and simulation tools can be applied to create comprehensive optical models of solar concentrating systems.

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Терещенко, В. С. "Модернізація двовісного автономного сонячного трекеру з інтелектуальною системою на базі контролерів Steca та Arduino". Master's thesis, Сумський державний університет, 2019. http://essuir.sumdu.edu.ua/handle/123456789/76114.

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Описані переваги та недоліки сонячних панелей. Описані основні принципи побудови різних систем орієнтування сонячних панелей за Сонцем. Розрахована сонячна інсоляція для м. Суми. Проведено моделювання роботи системи геліотрекеру в середовищі TinkerCad. Проведено моделювання впливу температури на ККД панелі в програмному комплексі MatLab. Модернізований лабораторний двовісний автономний сонячний трекер з інтелектуальною системою на базі контроллерів Steca та Arduino.

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Суходуб, С. С. "Модернізація двовісної автономної трекінгової системи для підвищення ефективності перетворення сонячної енергії". Master's thesis, Сумський державний університет, 2019. http://essuir.sumdu.edu.ua/handle/123456789/76129.

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Проведено аналіз підвищення енергетичної ефективності технологій фотоелектричних перетворювачів для сонячної енергетики. Представлено переваги та недоліки використання сучасних фотоелектричних систем, як основних компонентів фотовольтаніки. В роботі також запропоновано шляхи підвищення ефективності виходу електроенергії напівпровідникових фотоелементів за допомогою двовісної автономної GPS-трекінгової системи для підвищення ефективності перетворення сонячної енергії, аналіз енергетичних можливостей сонячного випромінювання для конкретних координат.

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Galle, Sylvie. "Analyse des champs spatiaux par utilisation de la télédétection : estimation de la durée quotidienne d'insolation en France à l'aide d'images du satellite Météosat et de mesures sol." Phd thesis, Grenoble INPG, 1987. http://tel.archives-ouvertes.fr/tel-00694114.

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L'insolation est étudiée, à l'échelle synoptique (la France) à l'aide d'un ensemble de mesures de la durée quotidienne d'insolation réalisées au sol et par télédétection satellitaire. L'objectif poursuivi est d'analyser une série de données suffi* samment longue pour caractériser de manière statistique le comportement climatologique de l'insolation dans l'espace. Les données sont fournies par 88 héliographes du réseau synoptique français ainsi que par le programme " Cactus " de la Météorologie Nationale, qui utilise les images visibles du satellite Météosat. L'étude porte sur une année de données. La similarité de la structure spatiale des mesures du sol et du satellite est montrée par analyse objective, et par analyse en composantes principales de processus. La fine perception de la variabilité spatiale du satellite est alors utilisée pour optimiser un réseau de mesures au sol. Les performances du programme Cactus sont comparées avec celles de méthodes d'interpolation classiques (basées sur 23 héliographes), pour l'estimation du rapport d'insolation. Elles se sont révélées plus performantes en terme de cofluctuation. Il apparaît cependant une tendance du satellite à exagérer les valeurs extrêmes. L'étalonnage des mesures satellitaires par des mesures sol a pour but de conjuguer les qualités de précision des hélio* graphes, et la définition spatiale du satellite. Une approche géostatistique est proposée. L'effet recherché est observé à partir d'une certaine densité du réseau d'étalonnage

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Pangaribuan, Charles. "Etude theorique d'un insolateur mixte utilisant l'eau et l'air comme fluides caloporteurs." Paris 6, 1988. http://www.theses.fr/1988PA066462.

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Simulation, a l'aide d'un ordinateur, du comportement d'un insolateur mixte a eau et a air, les deux fluides caloporteurs circulant dans le meme sens ou en sens contraire. Determination de la duree du regime transitoire. Calcul, en regime permanent, des distributions spatio-temporelles des temperatures dans ces divers elements, des puissances thermiques vehiculees par chaque fluide et de son rendement global

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Castro, Perez Denis Roberto 1946. "O envelope solar e o direito ao sol." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/258324.

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Orientador: Edison Favero Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo Made available in DSpace on 2018-08-09T08:54:17Z (GMT). No. of bitstreams: 1 CastroPerez_DenisRoberto_M.pdf: 10998353 bytes, checksum: 0e04f9184b6982b9301f851aa3849138 (MD5) Previous issue date: 2007 Resumo: Este trabalho apresenta um estudo que investiga formas de regulamentação de acesso ao sol e da sua qualificação, nos processos de planejamento urbano e projeto do edifício. Pela grande disponibilidade de sol e luz natural no país, torna-se recomendável esta regulamentação. Com o aprofundamento do conhecimento do envelope solar e a introdução do seu conceito nas legislações urbanísticas, é possível garantir o direito, em legislação específica, do acesso ao sol conforme determinantes climáticas. Esta pesquisa visa a proposição de subsídios para a reformulação e adequação, ou criação de novas legislações, bem como conscientizar o Poder Público para o uso do envelope solar e de outras condicionantes na emissão de diretrizes que servirão para dar início ao projeto arquitetônico. A pesquisa foi norteada pela construção dos envelopes solares, por latitude, orientação, em determinadas horas no solstício de inverno, em zonas urbanas do município de Campinas com distintas densidades. Com o auxílio de ferramentas CAD e de outros programas de computação, foram construídos os envelopes solares que serviram de base para a obtenção de dados e análises das relações entre os índices urbanísticos com as características físicas dos terrenos, edifícios, vizinhança, densidades, insolação e sombreamento, com a verificação da legislação local. Finalmente, são apresentados os resultados obtidos - conclusões que poderão contribuir para o crescimento urbano organizado e sustentável, abrindo novas possibilidades de projetos para o desenho urbano e a arquitetura Abstract: This work presents a study that investigates forms of regulation of access to the sun and its qualification, in the processes of urban planning and project of the building. Given the great availability of sun and natural light in the country, this regulation becomes recommendable. With the spread of the knowledge about the solar envelope and the introduction of its concept in the urbanistic legislations, it is possible to guarantee the right to the sun access according to specific climatic conditions. This research aims at the proposal of subsidies for the reformularization and adequacy, or creation of new legislations, as well as to acquire knowledge the Public Power for the use of the solar envelope and other directivies to the architectural project. The research was guided by the construction of the solar envelopes, by latitude, orientation, in determined hours in the winter solstice, in urban zones of the city of Campinas with distinct densities. With the aid of CAD tools and other programs of computation, the constructed solar envelopes that had served as basis for the attainment of data and analyses of the relations between the urbanistic indexes and the physical characteristics of lands, buildings, neighborhood, densities, insolation and shadowing, with the verification of the local legislation. Finally, conclusions are presented the gotten results - that will be able to contribute for the organized and sustainable urban growth, opening new possibilities of projects for the urban drawing and architecture Mestrado Arquitetura e Construção Mestre em Engenharia Civil

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FREITAS, Juliana Gomes de. "A influência das condições climáticas na durabilidade dos revestimentos de fachada: estudo de caso na cidade de Goiânia GO." Universidade Federal de Goiás, 2012. http://repositorio.bc.ufg.br/tede/handle/tde/1346.

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Made available in DSpace on 2014-07-29T15:18:24Z (GMT). No. of bitstreams: 1 Dissertacao_Juliana Gomes de Freitas - parte 1.pdf: 1986084 bytes, checksum: 775092561e5ebbcb68aef7acbe0f2a91 (MD5) Previous issue date: 2012-08-29 The climatic elements are related to the deterioration of the facades of buildings. Understanding the joint action of rain, wind and sunshine is important for prevention of pathological manifestations, thus ensuring the durability of coatings. Then, it becomes essential to know about the mechanisms of heat and moisture in porous materials. The problems related to this phenomenon are many, including the dimensional variation, which can cause cracks. The solar orientation and the presence of architectural details on the facades can cause the existence of the wettest spots, which favors the deposition of pollutants and microorganisms, causing stains. Thus, this paper aims at analyzing and understanding of issues that address the durability of facade coatings based on the understanding of the influence of climatic factors in buildings of the School of Engineering of the Federal University of Goiás (UFG), in Goiânia. Methodologically, the study aimed to: conducting a survey in order to quantify and map the pathological manifestations present, measurements of surface temperature and humidity in the dry and rainy seasons, trying to relate them to the cardinal orientations, creation of maps of wind-driven rain using data from the meteorological station of UFG, and conducting thermographic images, also in the rainy and dry seasons. The main results, it was found that the facades are exposed to different levels of humidity and temperature, which may favor the further deterioration of these. It was found that the north façade is the one that receives more sunlight in both the rainy and dry season, contributing to a high rate of fissuration. The same orientation is also one of the most humid and with higher levels of staining, consolidated information through wind-driven rain, that in the months of January and February 2012 reached one of the highest values. It was also observed that among the sites chosen for the measurements of surface moisture and temperature, the more prone to deterioration are the architectural details, as reached the highest values. In relation to infrared thermography, it was found that the best time of year for inspections was in the dry season and in the afternoon. In these periods, it was possible to identify pathological manifestations in the facades, such as stains, cracks and fantômes. An example is the case of the cracks which had a temperature 1°C lower than the part of the masonry without defects. It was also possible to visualize moist spots, as well as the lining of the points that were on the masonry and structure. A deterioração das fachadas dos edifícios está relacionada com os elementos climáticos. A compreensão da ação conjunta da chuva, vento e insolação é importante para prevenção de manifestações patológicas, garantindo, assim, a durabilidade dos revestimentos. Para tanto, torna-se essencial o conhecimento a respeito dos mecanismos de transporte de calor e umidade em materiais porosos. Os problemas relacionados a estes fenômenos são diversos, dentre eles a variação dimensional, que pode ocasionar fissuras. A orientação solar e a presença de detalhes arquitetônicos nas fachadas podem provocar a existência de pontos mais úmidos, o que favorece a deposição de poluentes e a proliferação de microorganismos, causando manchamentos. Deste modo, o presente trabalho objetiva a análise e entendimento de aspectos que visem à durabilidade dos revestimentos de fachadas a partir da compreensão da influência dos fatores climáticos em edifícios da Escola de Engenharia da Universidade Federal de Goiás (UFG), na cidade de Goiânia - GO. Metodologicamente, o estudo propôs-se à: realização de uma vistoria, com o intuito de quantificar e mapear as manifestações patológicas presentes; medições de temperatura e umidade superficiais nas estações seca e chuvosa, buscando relacioná-las com as orientações cardeais; cálculo do índice de chuva dirigida direcional mensal utilizando os dados da estação meteorológica da UFG; e realização de imagens termográficas, também nos períodos seco e chuvoso. Como principais resultados, verificou-se que as fachadas estão expostas a diferentes níveis de umidade e temperatura, o que pode favorecer a maior deterioração destas. Constatou-se que a fachada Norte é a que recebe mais insolação tanto no período seco quanto no chuvoso, contribuindo para um alto índice de fissuração. A mesma orientação também é uma das mais úmidas e com maiores níveis de manchamento, informação consolidada por meio do índice de chuva dirigida direcional que, nos meses de janeiro e fevereiro de 2012, atingiu um dos valores mais altos. Observou-se também que, dentre os locais escolhidos para as medições de umidade e temperatura superficiais, o mais propício à deterioração são os detalhes arquitetônicos, pois atingiram os mais altos valores. Em relação à termografia infravermelha, constatou-se que o melhor período do ano para as inspeções era na época seca e no horário da tarde. Nestes períodos, foi possível a identificação de manifestações patológicas nas fachadas, como manchas, fissuras e fantômes. Um exemplo é o caso das fissuras que possuíam temperatura 1°C menor que a parte da alvenaria sem defeitos. Foi possível a também a visualização de pontos úmidos, bem como dos pontos do revestimento que estavam sobre a alvenaria e a estrutura.

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Njomo, Donatien. "Contribution a l'etude d'un distillateur solaire a effet de serre : modelisation des transferts radiatifs, thermiques et de matiere couples dans un distillateur a ruisselement utilisant un stockage d'energie par chaleur latente." Poitiers, 1987. http://www.theses.fr/1987POIT2274.

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Modelisation des echanges radiatifs et de matiere couples regissant le fonctionnement d'un distillateur solaire a effet de serre. On etablit des correlations empiriques permettant d'evaluer le gisement solaire de poitiers. Sur le plan technique, on ameliore le rendement d'un distillateur classique a ruissellement de type courants croises : a(avec la circulation en aller-retour du liquide a distiller), b(en utilisant un echangeur pour prechauffer la solution a distiller), c(en utilisant un stokage d'energie par chaleur latente). Traitement numerique des parametres de la distillation solaire. Comparaison aux resultats experimentaux obtenus avec un simulateur de raisonnement

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Анна, Буркач, Burkach Ann, Сукач Тимур та ін. "Символ величі університету – «стіни, які повити плющем» (до 85-річчя НАУ)". Thesis, Київський національний університет будівництва та архітектури, 2019. http://er.nau.edu.ua/handle/NAU/40698.

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[1] Ландшафтні рішення для друзів НАУ. – URL: https://nau.edu.ua/ua/news/1/6/landshaftni-rishennya-dlya-druziv-nau.html?fbclid=IwAR1lfRxU9G543L454lEj7v_qa_L57ESJZBzCnp5zf9ZZpjoJAFbUErTL5uo [2] Чемакіна, О. В. Інженерний благоустрій населених міст: навч. посіб. / О. В. Чемакіна, Г. М. Агєєва. – К.: НАУ, 2017. – 168 с. [3] Экологичный жилой дом в Валенсии. – URL: https://costablancalive.es/yekologichnyy-zhiloy-dom-v-valensii/ [4] Цигипко, С. П. Особливості реконструкції історичної забудови і екологічне нормування / С. П. Цигипко // Комунальне господарство міст. – 2011. – Вип.99. – С.499-505. [5] Перевірено стан території та навчальних корпусів НАУ. – URL: https://nau.edu.ua/ua/news/2019/7/perevireno-stan-teritorii-ta-navchalnih-korpusiv-nau.html [6] Римшин, В. И. Практика нормирования солнцезащитных устройств / В. И. Римшин, С. А. Сёмин, А. В. Спиридонов, И. Л. Шубин // Светотехника. – 2014. – №6. – С.27-31. Представлені результати дослідження можливості уникнення надмірного інсоляційного режиму приміщень будівель НАУ за допомогою архітектурно-планувальних, конструктивних рішень та вертикального озеленення фасадів Представлены результаты исследования возможности снижения чрезмерного инсоляционного режима помещений зданий НАУ с помощью архитектурно-планировочных, конструктивных решений и вертикального озеленения фасадов. The results of researching possibility of avoiding excessive insolation regime of NAU buildings by architectural planning, structural solutions and vertical landscaping of the facades are presented.

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Mihindukulasooriya, Lorita Nivanthi. "A multi-proxy reconstruction of paleolimnology and paleoclimatic variability using authigenic lake carbonates from Cleland Lake, British Columbia." Kent State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=kent1416567848.

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Barreto, Eline Alves de Souza. "Reconstituição da pluviosidade da Chapada Diamantina (BA) durante o Quaternário Tardio através de registros isotópicos (O e C) em estalagmites." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/44/44142/tde-24052010-183923/.

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Registros das razões isotópicas do oxigênio (d18O) e do carbono (d13C), juntamente com as taxas de crescimento de espeleotemas, precisamente datados pelo método U/Th, foram utilizados para reconstituição das variações de pluviosidade dos últimos 93 mil anos A.P. na região da Chapada Diamantina, porção central do Estado da Bahia. A reconstituição paleoclimática foi apoiada por estudo de calibração realizado em duas cavernas da região estudada, através do qual se obteve boa relação entre a assinatura isotópica da chuva e do d18O dos gotejamentos e evidências de condições ambientais propícias para deposição de espeleotemas em equilíbrio isotópico com a água de gotejamento. A interpretação climática dos dados de d18O dos espeleotemas considera também a análise da composição isotópica da água da chuva em face da pluviometria, a partir de dados de estações do IAEA-GNIP no Brasil e de simulações das variações do d18O da chuva através do modelo climático ECHAM-4. Esses dados indicam o fator amount effect, como relação preponderante na discussão de pluviosidade através dos registros de espeleotemas, a qual é caracterizada pela diminuição dos valores de d18O com o aumento do volume de chuvas. A partir dos registros de d18O dos espeleotemas foi possível reconstituir os padrões regionais de pluviosidade segundo o ciclo de insolação, como também identificar eventos de mudança abrupta de pluviosidade em escala milenar ocorridos durante o último período glacial e Holoceno. Em escala orbital, foi observado aumento (diminuição) da paleoprecipitação na Bahia durante fases de baixa (alta) insolação de verão (10ºS). Essa relação é evidente na maior parte do registro baiano com exceção do período entre 40 e 20 ky A.P., quando houve predomínio de clima seco, mesmo em fases de insolação baixa. No entanto, tal é relação inversa a que foi descrita em estudos paleoclimáticos do Sul/Sudeste do Brasil e dos Andes. Além disso, variações de paleopluviosidade da Chapada Diamantina estão em fase com as registradas nos trópicos do Hemisfério Norte, na China e Venezuela. Esses resultados indicam influência direta do sistema de Monções Sul-americana (MSA) sobre o regime de chuvas do Nordeste em longa escala de tempo, a qual é primariamente modulada pela intensidade da insolação de verão. Aumentos abruptos da paleopluviosidade em escala milenar, indicados por baixos valores de d18O e d13C, como pelas altas taxas de crescimento de espeleotemas, ocorreram durante predomínio de condições frias no Atlântico Norte, em períodos de grandes mudanças nas condições oceânicas, e são concomitantes com os eventos Heinrich e Younger Dryas. Já fortes diminuições foram observadas durante alguns eventos Dansgaard-Oeschger e Bølling-Allerød. Ao contrário do que foi observado durante os ciclos orbitais, o impacto no clima da Bahia atribuído a esses eventos é semelhante em todo país e também nos Andes, de acordo com estudo comparativo entre testemunhos marinhos/lacustres e espeleotemas. Esses eventos produz efeito na pluviosidade de regiões (sub)tropicais do Hemisfério Norte, assim como registrados em arquivos paleoclimáticos da China e Venezuela. O mecanismo mais provável para geração desses eventos está relacionado com mudanças na Atlantic Meridional Overturning Circulation (AMOC). Com a AMOC desintensificada durante eventos Heinrich no Hemisfério Norte, existe predomínio de um gradiente da temperatura da superfície do Atlântico tropical que favorece posicionamento da Zona de Convergência Intertropical mais a sul durante os eventos úmidos na Bahia. Speleothem records of stable oxygen (d18O) and carbon isotope ratios (d13C) and speleothem growth rates, precisely dated by U/Th method, were used to reconstruct past changes in precipitation in the last 93,000 years B.P. from Chapada Diamantina region, Bahia State. The paleoclimatic reconstruction takes into account results from a calibration study performed in two caves in the Chapada Diamantina region. It was found a robust relationship between isotope signature in precipitation and cave drip water and also evidenced adequate environmental conditions for speleothem deposition in isotopic equilibrium with drip water. The interpretation of the speleothem d18O records is based on the relationship between isotope composition of precipitation and rainfall amount from IAEA-GNIP stations in Brazil and also results from climate experiments coupled with d18O in precipitation using ECHAM-4. These data indicate the amount effect as the dominant isotope fractionation factor controlling the d18O variations in meteoric water forming speleothems, which is characterized by a decrease in the d18O values with an increase in rainfall amount. Speleothem d18O records allow reconstructing the regional paleoprecipitation patterns on both orbital and millennial time-scales during last glacial period and Holocene. These records indicate an increase (decrease) in paleoprecipitation over central Bahia during low (high) summer insolation (10ºS) phases. This relationship is evident is most of this new speleothem record, except in the period between 40 and 20 ka B.P., when dry climate conditions predominate in the region even during the low insolation phases. However, this relationship is exactly the contrary of the one reported from southern/southeastern Brazil and Central Andes paleoclimate studies. Furthermore, the precipitation variations in Chapada Diamantina are in phase with records from Northern Hemisphere on orbital time-scales, particularly from China and Venezuela. These results suggest a direct influence of the South American Monsoon System (SAMS) on long-term changes in precipitation over northeastern Brazil, which is primarily controlled by gradual changes in summer insolation. Abrupt wet events are defined on millennial time-scales in the Chapada Diamantina records by low values of d18O e d13C and high speleothem growth rates. They occurred under prevalence of cold conditions in Northern Hemisphere, triggered by major changes in oceanic circulation in Atlantic Ocean, during Heinrich and Younger Dryas (YD) events. On the other hand, abrupt decreases in regional precipitation are coincident with some of the Dansgaard-Oeschger (D-O) e Bølling-Allerød (B-A), which are typical warm events in Northern Hemisphere. However, differently from the isotope-climate relationship established on orbital times, the impact of these millennial events on the precipitation variations of Bahia is similar to what is documented in speleothem, lake and marine records from Brazil and Central Andes and opposite to changes described in China and Venezuela, among many other records from Northern Hemisphere. The climate mechanism behind the origin of these millennial events is associated with changes in the Atlantic Meridional Overturning Circulation (AMOC). The Heinrich events are linked to periods of weaker AMOC and sea surface temperature gradients that favor a mean southern position of Intertropical Convergence Zone, which results in very wet conditions in Bahia.

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Abebe, Nardos Tilahun. "Paleohydrology of West Africa Using Carbonate, Detrital and Diagenetic Minerals of Lake Bosumtwi, Ghana." University of Akron / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=akron1271102396.

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Salgado, Paula Rodrigues. "Fenóis totais no cafeeiro em razão das fases de frutificação e do clima." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-26042005-145455/.

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Os vegetais apresentam defesa natural contra os fatores externos, bióticos e abióticos, por meio da síntese de compostos fenólicos no metabolismo secundário, as quais variam com as fases fenológicas e com o clima. O aumento dos compostos fenólicos nas plantas está, diretamente, relacionado com a resistência à infecção por patógenos e à infestação de pragas. Entretanto, pouco se sabe sobre a variação dos teores dessa substância durante os estádios fenológicos do cafeeiro, em particular, nas fases de frutificação, e em razão das condições climáticas. Tais conhecimentos são fundamentais para a previsão dos riscos de ataques aos vegetais, uma vez que a defesa natural da planta deve mudar ao longo do ciclo. O experimento foi realizado em uma cultura de Coffea arabica L., cultivar Obatã IAC 1669-20, instalada no campo experimental do Departamento de Produção Vegetal, da Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Piracicaba/SP. Para a realização do experimento foi adotado o delineamento experimental inteiramente casualizado, utilizando quatro tratamentos (plantas com e sem frutos - folhas dreno e plantas com e sem frutos - folhas fonte) e cinco repetições constituídas por plantas individuais. Após a análise de variância dos resultados foi aplicado o teste t de Student ao nível de 5 % de significância para a comparação das médias entre os tratamentos. Os teores de fenóis totais (µg g-1) foram extraídos das folhas maduras (fonte) e novas (dreno) e analisados em relação à produção de café, fenologia e clima. As variáveis climáticas adotadas foram temperatura atmosférica (média, mínima e máxima; oC), radiação global (MJ m-2 dia-1) e insolação diária (h dia-1). Durante a condução do experimento foram realizadas avaliações de altura da planta (cm), diâmetro do caule (mm) e comprimento de ramos plagiotrópicos (cm) para determinar as respectivas taxas de crescimento vegetativo das plantas. As quantidades de fenóis totais determinadas nas plantas com produção (17.40 µg g-1 e 13.89 µg g-1 folhas dreno e fonte, respectivamente) e sem produção de café (18.65 µg g-1 e 12.76 µg g-1 folhas dreno e fonte, nessa ordem) não variaram. No entanto, a concentração de fenóis totais nas folhas novas (dreno) das plantas com e sem produção de café foi maior que a quantidade determinada nas folhas maduras (fonte), da ordem de 25 % e 46 %, respectivamente. A síntese de fenóis nas fases de expansão (16.35 µg g-1) e granação dos frutos (14.68 µg g-1) foi 31 % inferior em relação às quantidades determinadas na fase de maior produção dessas substâncias fruto em maturação (21.24 µg g-1). A metabolização de fenóis totais depende, indiretamente, da temperatura (oC) e da radiação global (MJ m-2 dia-1), apresentando tendência inversa em relação a estas variáveis climáticas. A orientação do manejo fitossanitário deve levar em consideração as épocas em que há comprometimento da defesa natural da planta, em relação à produção de substâncias protetivas os fenóis. The vegetables show a natural defense against external factors, biotic and abiotic, by the synthesis of the phenolic compounds in the secondary metabolism, which varies with the maturity state and with the climate. The increase of phenolic compounds in the plants is directly related to the resistance to the infection thought pathogens and insect infestation. However, little is known about the variation in the content of this substance during the maturity state of the coffee tree, particularly in the fructification phases due to the climatic variations. Such knowledge is the base for the risks analyses of attacks to vegetables, since the natural defense of the plant shall change during the cycle. The experiment was carried out in a Coffea arabica L. crop, to cultivar Obatã IAC 1669-20, installed in the experimental field of the department of vegetal production of the Escola Superior de Agricultura "Luiz de Queiroz", University of São Paulo, Piracicaba/SP. For the accomplishment of the experiment it was adopted a totally randomized experimental design, using four treatments (plants with and without fruits drain leaves and plants with and without fruits source leaves) and five repetitions consisting of individual plants. After analysing the variance of the results it was applied Student t test at the level of 5 % of significance to compare the averages between the treatments. The total phenol grade (µg g-1) have been extracted from the mature (source) and new (drain) leaves and have been analyzed in relation to the coffee yield, phenology and climate. The climatic conditions adopted were atmospheric temperature (average, minimum and maximum; oC), global radiation (MJ m-2 day-1) and daily insolation (h day-1). During the conduction of the experiment it was analyzed the evaluations of the height (cm), diameter (mm) and length of the reproductive branches (cm) to determine the respective vegetative growth rates of the plants. The determined amounts of total phenols in the plants with production (17.40 µg g-1 and 13.89 µg g-1 drain and source leaves, respectively) and without coffee production (18.65 µg g-1 and 12.76 µg g-1 drain and source leaves, respectively) did not varied. However, the total phenol concentrations in new leaves of the plants with and without coffee production were greater than the amount determined in mature leaves around 25 % and 46 %, respectively. The secondary substance synthesis in the phases of expansion (16.35 µg g-1) and grain filling of the fruits (14.68 µg g-1) was 31% lower than the amounts determined in the phase of the greatest production of these substances - fruit in maturation (21.24 µg g-1). The total phenol metabolization depends indirectly on the temperature (oC) and on the global radiation (MJ m-2 day-1), presenting inverse trend in relation to these climatic variable. The orientation of the crop protection managing shall take into consideration the period when it has endangerment of the natural defense of the plant.

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Schick, Andreas Michael. "Height, Human Capital, and Economic Growth." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1306273610.

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Gábrová, Lenka. "Analýza technických požadavků na stavby se zaměřením na stavební fyziku." Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-232686.

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The Thesis "Analysis of Technical Requirements for Buildings with focus on Building Physics" deals with the solution of masonry and monolithic residential buildings in terms of building physic requirements primarily listed in Decree No.268/2009 Coll and in Czech technical standards.

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35

Hanschmann, Timo. "Unsicherheiten in der Erfassung des kurzwelligen Wolkenstrahlungseffektes." Doctoral thesis, Universitätsbibliothek Leipzig, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-137323.

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Diese Arbeit betrachtet die Wechselwirkung von solarer Einstrahlung mit Wolken in der Atmosphäre. Diese wird insbesondere repräsentiert durch den Wolkenstrahlungseffekt. Hierbei wurde vor allem auf die Auswirkungen von kleinskaliger Variabilität von Wolken und Wolkenfeldern auf die Genauigkeit des Wolkenstrahlungseffektes am Oberrand der Atmosphäre und am Boden Rücksicht genommen. Mit einer Schliessungsstudie ist der modellierte Wolkenstrahlungseffekt mit Schiffsmessungen verglichen worden. Hierbei wurden die Wolkeneigenschaften in dem Modell durch Schiffs- und Satellitendaten als Eingangsdatensatz beschrieben. Ein Zugewinn in der Genauigkeit konnte durch die kombinierte Nutzung beider Datenquellen erzielt werden, konkret durch die Kombination des Flüssigwasserpfads aus Schiffsmessungen und des effektiven Radius aus Satellitenbeobachtungen. Durch die Schliessungsstudie sind zwei Probleme in der Auflösung kleinskaliger Bewölkung und deren Auswirkung auf abgeleitete Wolkeneigenschaften identifiziert worden, die im weiteren Verlauf der Arbeit genauer betrachtet wurden. Ein Vergleich zweier Methoden zur Erkennung des Bedeckungsgrades, jeweils eine vom Boden und eine vom Oberrand der Atmosphäre, hat insgesamt eine gute Übereinstimmung ergeben. Jedoch zeigten sich Abweichungen bei geringer Bedeckung. So wurde bei einem Bedeckungsgrad von ca. 40% in der Hälfte der Fälle den Satellitenbildpunkt als bewölkt klassifiziert. Diese Unsicherheiten in der Klassifikation konnten auf die abgeleitete reflektierte solare Einstrahlung übertragen werden. Für als unbewölkt erkannte, tatsächlich aber bewölkte, Bildpunkte wurde eine mittlere Überschätzung der reflektierte solare Einstrahlung von ca. 30 W/m−2 gefunden. Ebenfalls wurde der Einfluss der zeitlichen Variabilität in der solaren Einstrahlung auf die Bestimmung des Wolkenstrahlungseffektes einer Wolke untersucht. Hierfür wurde ein lineares Modell entwickelt und präsentiert, das die diffuse Einstrahlung mit dem Bedeckungsgrad in Zusammenhang stellt. Das Modell liefert zwei Koeffizienten, die die Variation der diffusen Einstrahlung durch eine Wolke unter der Annahme, dass die beobachtete Wolke den ganzen Himmel bedeckt, beschreiben. Dies ermöglicht einen direkten Vergleich des Wolkenstrahlungseffektes einer beobachteten Wolke mit Modellergebnissen und die Entkopplung von der zeitlich variablen direkten Einstrahlung.

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36

Касяненко, Артем Вікторович. "Врахування потенціалу сонячної електричної станції встановленої на даху багатоквартирного будинку при виборі елементів системи електропостачання". Bachelor's thesis, КПІ ім. Ігоря Сікорського, 2021. https://ela.kpi.ua/handle/123456789/43038.

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Під час виконання дипломного проєкту було виконано розрахунок житлового району, живлячі мережі до 1кВ та вище 1, також під час розрахунків було вибрано силові трансформатори, апарати захисту та автоматики. Проведено розрахунок струмів короткого замикання. У спец. питанні було проведено дослідження ефективності встановлення СЕС на даху багатоквартирного будинку. During the implementation of the diploma project, the calculation of the residential area, the network of which reaches more than 1 kV, was performed, and during the calculations, power transformers, automation and protection equipment were selected. In a special issue, a study was conducted on the effectiveness of installing SES on the roof of an apartment building.

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Flüeler, Marie-Josèphe. "Etude des macroinvertébrés -surtout des diptères- pour trois ruisseaux de plaine." Grenoble 1, 1986. http://www.theses.fr/1986GRE10045.

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Pour 3 ruisseaux lents de plaine dans le departement de l'isere, les caracteres du milieu et la composition de la faune sont indiques. Les principaux facteurs qui determinent la repartition des especes sont examines

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38

Hanschmann, Timo. "Unsicherheiten in der Erfassung des kurzwelligen Wolkenstrahlungseffektes." Doctoral thesis, Leibniz Institut für Troposphärenforschung, 2013. https://ul.qucosa.de/id/qucosa%3A12324.

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Diese Arbeit betrachtet die Wechselwirkung von solarer Einstrahlung mit Wolken in der Atmosphäre. Diese wird insbesondere repräsentiert durch den Wolkenstrahlungseffekt. Hierbei wurde vor allem auf die Auswirkungen von kleinskaliger Variabilität von Wolken und Wolkenfeldern auf die Genauigkeit des Wolkenstrahlungseffektes am Oberrand der Atmosphäre und am Boden Rücksicht genommen. Mit einer Schliessungsstudie ist der modellierte Wolkenstrahlungseffekt mit Schiffsmessungen verglichen worden. Hierbei wurden die Wolkeneigenschaften in dem Modell durch Schiffs- und Satellitendaten als Eingangsdatensatz beschrieben. Ein Zugewinn in der Genauigkeit konnte durch die kombinierte Nutzung beider Datenquellen erzielt werden, konkret durch die Kombination des Flüssigwasserpfads aus Schiffsmessungen und des effektiven Radius aus Satellitenbeobachtungen. Durch die Schliessungsstudie sind zwei Probleme in der Auflösung kleinskaliger Bewölkung und deren Auswirkung auf abgeleitete Wolkeneigenschaften identifiziert worden, die im weiteren Verlauf der Arbeit genauer betrachtet wurden. Ein Vergleich zweier Methoden zur Erkennung des Bedeckungsgrades, jeweils eine vom Boden und eine vom Oberrand der Atmosphäre, hat insgesamt eine gute Übereinstimmung ergeben. Jedoch zeigten sich Abweichungen bei geringer Bedeckung. So wurde bei einem Bedeckungsgrad von ca. 40% in der Hälfte der Fälle den Satellitenbildpunkt als bewölkt klassifiziert. Diese Unsicherheiten in der Klassifikation konnten auf die abgeleitete reflektierte solare Einstrahlung übertragen werden. Für als unbewölkt erkannte, tatsächlich aber bewölkte, Bildpunkte wurde eine mittlere Überschätzung der reflektierte solare Einstrahlung von ca. 30 W/m−2 gefunden. Ebenfalls wurde der Einfluss der zeitlichen Variabilität in der solaren Einstrahlung auf die Bestimmung des Wolkenstrahlungseffektes einer Wolke untersucht. Hierfür wurde ein lineares Modell entwickelt und präsentiert, das die diffuse Einstrahlung mit dem Bedeckungsgrad in Zusammenhang stellt. Das Modell liefert zwei Koeffizienten, die die Variation der diffusen Einstrahlung durch eine Wolke unter der Annahme, dass die beobachtete Wolke den ganzen Himmel bedeckt, beschreiben. Dies ermöglicht einen direkten Vergleich des Wolkenstrahlungseffektes einer beobachteten Wolke mit Modellergebnissen und die Entkopplung von der zeitlich variablen direkten Einstrahlung.

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Dinh, Thi Mong Cam. "Influence des conditions d'élaboration sur les transformations de phases dans les couches minces de cobaltites de fer à structure spinelle." Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30090.

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Des films minces spinelles de cobaltites de fer Co1,7Fe1,3O4 dont la composition se situe dans la lacune de miscibilité du diagramme de phases CoFe2O4-Co3O4, ont été préparés par pulvérisation cathodique RF au voisinage de la température ambiante. Les films obtenus, dont les épaisseurs de 300 nm ont été fixées, sont constitués de cristallites de diamètre moyen proche de 20 nm. Le traitement à 600 °C pendant plusieurs heures de ces échantillons conduit à la formation de deux phases spinelles, en accord avec le diagramme de phases. Cette transformation a été clairement établie, à la fois par la diffraction des rayons X et la spectroscopie Raman. Dans les cobaltites de fer "massifs" de compositions proches ou identiques, une telle transformation est de type spinodal et se caractérise par une organisation pseudo-périodique à une échelle de quelques dizaines de nanomètres, de phases spinelles riches en fer et riches en cobalt. Dans le but de mettre en évidence cette organisation dans les couches minces, différentes études de microscopie ont été menées. Un procédé de préparation spécifique a même été développé pour découper des lames minces, parallèlement au plan de la couche, par la technique du faisceau d'ions focalisé (FIB). Les cristallites peuvent ainsi être observées et étudiées individuellement. Les analyses n'ont rien révélé cependant, et dans le meilleur des cas, c'est-à-dire pour les cristallites les plus grosses, seule la présence de deux zones de compositions différentes a pu être constatée. L'alternance pseudo-périodique attendue n'a donc pas pu être observée. Il semble ainsi que la taille nanométrique des cristallites empêche l'établissement d'une transformation spinodale telle qu'elle peut être mise en évidence dans les échantillons "massifs". L'observation d'anomalies de composition dans les joints de grains corrobore cette hypothèse qui suggère un effet " nano " sur la transformation de phase. Au cours du présent travail, il a été en outre constaté qu'en plus de la température et du temps de recuit, les conditions de pulvérisation ont également un impact important sur la formation et la décomposition des phases dans les couches minces. Bien que cette étude n'ait pas trouvé les conditions de dépôt qui conduisent directement à la formation de deux phases spinelles dès la pulvérisation, elle montre toutefois que certaines conditions permettent d'écourter les temps de recuit tout en abaissant les températures requises pour effectuer la transformation recherchée. Pour la première fois, des couches de cobaltites de fer ont été soumises à des traitements sous faisceau laser afin de provoquer des transformations de phases en leur sein. Il a été montré que la formation de deux spinelles à partir d'une couche monophasée peut être réalisée dans des temps très courts et sous de faibles puissances, compte tenu probablement d'une élévation rapide et importante de la température locale, due à l'absorption du faisceau laser. Les nombreux paramètres offerts par la machine de photolithogravure mise en œuvre (puissance, vitesse de balayage, incrément du balayage, focalisation...) n'ont pu être explorés de manière exhaustive au cours de cette étude. Cette dernière ne doit donc être considérée que comme un travail préliminaire. Les résultats qu'elle livre sont toutefois prometteurs et font émerger une nouvelle voie de traitement, permettant de réaliser simplement des transformations de phases dans les cobaltites de fer Thin spinel films of Co1.7Fe1.3O4 iron cobaltites, whose composition is in the miscibility gap of the CoFe2O4-Co3O4 phase diagram, were prepared by RF sputtering near room temperature. The films obtained, whose thicknesses were fixed at 300 nm, consist of crystallites with a mean diameter close to 20 nm. The treatment of these samples at 600 °C for several hours leads to the formation of two spinel phases, in agreement with the phase diagram. This transformation was clearly established, both by X-ray diffraction and Raman spectroscopy. In "bulk" iron cobaltites of close or same compositions, such a transformation is of spinodal type and is characterized by a pseudo-periodic organization of rich iron and cobalt-rich spinel phases on a scale of a few tens of nanometers. In order to highlight this organization in the thin films, microscopy studies were carried out. A specific preparation process was even developed in order to cut in-plane thin sections, by the focused ion beam (FIB) technique. Crystallites can thus be observed and studied individually. The analyzes revealed, however, and in the best case (i.e. for the largest crystallites), the presence of only two zones of different compositions. The expected pseudo-periodic alternation could never be observed. It seems that the nanometric size of the crystallites, prevents the spinodal transformation which was highlighted in the "bulk" samples. The observation of local chemical anomalies in grain boundaries corroborates this hypothesis, which suggests a "nano" effect on phase transformation. For the present work, it was furthermore found that in addition to the temperature and the annealing time, the sputtering conditions also have a significant impact on the formation and decomposition of the phases in the thin films. Although this study did not find the deposition conditions that lead directly to the formation of two spinel phases after sputtering, it shows however that certain conditions shorten the annealing times while lowering the temperatures required to perform the targeted transformation. For the first time, iron cobaltite thin films were subjected to laser beam treatments to induce phase transformations within them. It was shown that the formation of two spinels from a single-phase film can be achieved in very short times and at low laser power, probably because of a rapid and high rise of local temperature, due to the absorption of the laser beam. The numerous parameters offered by the photolithography machine used (power, scanning speed, scanning increment, focusing, etc.) could not be exhaustively explored during this study. The latter should therefore be considered only as a preliminary work. The results, however, are promising and seem to bring out a new treatment route, allowing simple phase transformations in iron cobaltites

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40

Smutný, Vojtěch. "Ověření možností pro zvýšení tepelně-izolační schopnosti pěnových plastů." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-225897.

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The thesis is devoted to the study of material properties of selected types of polystyrene, especially expression of the coefficient of linear thermal expansion. The work contains two main chapters, theoretical and practical. The theoretical part of the thesis deals with an overview of the thermal insulation in the Czech Republic, the description of phenomena related to heat transfer mechanisms and an overview of experimental methods for determining thermal insulating properties. The practical part presents results of measurements of samples with foamed polystyrene, which is modified by the addition of selected substances. The thesis describes the machine program, which is used to calculate the temperature in during the construction arrangement under the sunlight load.

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Vystrčil, Jan. "Mateřská školka v Jihlavě." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2020. http://www.nusl.cz/ntk/nusl-410113.

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In diploma thesis is elaborated project documentation for the construction of an building of kindergarten. The building is situated in peryphery of Jihlava city. The building is two-storey kindergarten building with a basement. There aure two classes for children 3 - 6 years old in the building. In diploma thesis is elaborated architect-building solutions, building – construction solutions, fire safety solutions and physics qualities of constructions.

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42

Bauer, Hugues. "Influence du climat, de l'eustatisme et de la tectonique dans l'architecture des séries continentales. Cas du Miocène inférieur et moyen du Bassin de Digne-Valensole (SE, France)." Phd thesis, École Nationale Supérieure des Mines de Paris, 2006. http://pastel.archives-ouvertes.fr/pastel-00002113.

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Le besoin de connaître toujours plus finement les réservoirs (pétrole/gaz, stockage du CO2, des déchets...) se heurte au problème de la résolution temporelle (stratigraphique), notamment pour les séries sédimentaires continentales. Leur géométrie dépend essentiellement de trois facteurs: les variations du niveau marin (eustatisme), la tectonique et le climat. Cette étude vise à comprendre leur rôle respectif dans l'architecture des dépôts continentaux miocènes (~13,5-23 Ma) du bassin de Digne, dont la stratigraphie est bien établie. L'analyse séquentielle des dépôts nous a permis de distinguer une zone Nord où sept séquences de 3e ordre sont enregistrées, et une zone Sud où la tectonique locale en a fait disparaître deux. La tectonique régionale a joué sur l'amplitude et l'âge des séquences en regard des correspondances établies avec la charte eustatique. Ses effets traduisent le déplacement des dépôtcentres au cours du remplissage du bassin. L'influence du climat a joué à différentes échelles de temps. A celle de l'Optimum Climatique du Miocène (14,6-16,5 Ma), caractérisé par trois phénomènes globaux (l'excursion isotopique du 13C - Monterey Event; un maximum transgressif; le développement maximal de la mangrove à Avicennia). A celle des cycles de 3e ordre du Langhien-Serravallien, dont l'origine climato-eustatique est attestée par la comparaison du découpage séquentiel avec l'analyse pollinique. A l'échelle des cycles de Milankovitch, dont ceux d'excentricité ont été observés dans les incursions marines, les cycles de précession et d'obliquité ayant été reconnus dans la distribution et le développement des paléosols, par comparaison directe avec le signal d'insolation.

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Sedláček, Jan. "Mateřská školka v Brně." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226522.

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The subject of this work is the solution of a new building of nursery school in the village of Ivanovice. It is a cellarless, two-storey building for 40 childern. The floor plan is „L“ shaped with orientation of the classes to the south and west which provide enough rate (amount) of insolation which support good mood and development of the childern. The object is situated in medium sloping land mainly in the area of familly and residential houses. The main entrance to the building is situated on the south from where si access road to the object too. Comfort parking is provided by ten parking places, one is determined for disabled people. The lighting and ventilation of all rooms is provided by windows. Roofing is solved using of wooden truss in combination with single casing roof.

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Šotkovský, David. "Zděný bytový dům." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226405.

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This Master´s thesis is focused on block of flats project documentation, claims for fire safety and thermal and acoustic properties of structures. The brick building is detached and has three floors without basement. These floors are connected by a lift. The block of flats is based on the footings, external walls are insulated by a contact thermal insulation system. The tent roof is consists of truss in two levels. The building is designed for nine flats and one of these flats is wheelchair accessible. Truss design is also a part of the project.

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Špalková, Martina. "Stavebně technologické řešení zdravotního střediska ve Vizovicích." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227163.

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The diploma thesis is based on a project of medical centre in Vizovice. The medical centre is designed as a three-floor building with a receding top floor. Building foundations are designed from foundation pads and strips from reinforced concrete, the load-bearing masonry is designed from hollow clay blocks ZELUS, a reinforced concrete ceiling is designed as a bracing element. The medical centre is roofed by a flat roof with a PVC covering. This thesis deals with the budget and time plan of the whole construction, transport accessibility of the building, building maintenance instructions and maintenance costs for 25 years, daylighting of room number 1.32, an engineering report of construction site equipment and its drawing, a design of lifting mechanism of the site equipment, a plan for transport of concrete and concreting the floor slabs. The thesis is mainly focused on roofing of the medical centre, technological regulation for the roofing and reinforced concrete floor slabs is elaborated, as well as a control and test plan for the floor slabs from the reinforced concrete and for the roof PVC foil.

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Jones, Adam Michael. "Design, Fabrication, and Characterization of High Density Silicon Photonic Components." Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/338939.

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Our burgeoning appetite for data relentlessly demands exponential scaling of computing and communications resources leading to an overbearing and ever-present drive to improve efficiency while reducing on-chip area even as photonic components expand to fill application spaces no longer satisfied by their electronic counterparts. With a high index contrast, low optical loss, and compatibility with the CMOS fabrication infrastructure, silicon-on-insulator technology delivers a mechanism by which efficient, sub-micron waveguides can be fabricated while enabling monolithic integration of photonic components and their associated electronic infrastructure. The result is a solution leveraging the superior bandwidth of optical signaling on a platform capable of delivering the optical analogue to Moore's Law scaling of transistor density. Device size is expected to end Moore's Law scaling in photonics as Maxwell's equations limit the extent to which this parameter may be reduced. The focus of the work presented here surrounds photonic device miniaturization and the development of 3D optical interconnects as approaches to optimize performance in densely integrated optical interconnects. In this dissertation, several technological barriers inhibiting widespread adoption of photonics in data communications and telecommunications are explored. First, examination of loss and crosstalk performance in silicon nitride over SOI waveguide crossings yields insight into the feasibility of 3D optical interconnects with the first experimental analysis of such a structure presented herein. A novel measurement platform utilizing a modified racetrack resonator is then presented enabling extraction of insertion loss data for highly efficient structures while requiring minimal on-chip area. Finally, pioneering work in understanding the statistical nature of doublet formation in microphotonic resonators is delivered with the resulting impact on resonant device design detailed.

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Ibrahim-Ouali, Lila. "Ecriture poétique et structures romanesques de l'oeuvre de Rachid Boudjedra." Clermont-Ferrand 2, 1995. http://www.theses.fr/1996CLF20087.

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La thèse étudie la forme des romans de Boudjera. La démarche méthodologique privilégie la dimension poétique de l'oeuvre et aborde accessoirement les éléments sociologiques et psychologiques lorsque ceux-ci s'agencent en structures signifiantes. L'étape initiale revèle le rôle prépondérant des interférences linguistiques et textuelles dans le fonctionnement poétique lesquelles requièrent la mise en place de statégies d'assemblage, d'intégration. . . Le metisssage du texte réserve un traitement différent aux autorités occidentales et arabo-islamiques. Dans les 2 cas les oeuvres de référence et de préférence permettent à R. Boudjera d'élaborer son mythe personnel sur une poétique subversive. La 2de étape considère la part d'engagement politique qui soutend les préocccupations esthétiques. La rhétorique de la critique (intertextualité et dialogisme) qui prend appui sur des archéthèmes est motivée par le désir qu'a l'auteur de raconter l'aventure d'une écriture et de bâtir une relation privilégiée avec un lecteur implicite qui multipliera le sens de son oeuvre ouverte The thesis's aim is the analysis of rachid boudjedra's french novels and specially their shape. The methodologic approach favours the poetic of the works and developpes in a secondary time the sociologic and psychologic elements as meaning structures. In the first part, we observ the linguistic and textual interferences of the text and the operations of "metissage" which build the "mythe personnel" of the subversif author. In the second part, we consider the critical rhetoric which lean on boudjedrian "archethemes". In fact, r. Boudjedra relates the writing's adventure and searches this implicit reader which will increase in number the "oeuvre ouverte"'s meanings

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Hiller, Marion D. E. "TRNSHD - a program for shading and insolation calculations." 1996. http://catalog.hathitrust.org/api/volumes/oclc/36679030.html.

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Thesis (M.S.)--University of Wisconsin--Madison, 1996. Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 149-150).

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How, Karl T. S. "Modelling sugarcane growth in response to age, insolation and temperature." Thesis, 1986. http://hdl.handle.net/10125/9974.

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Edgar, Ross. "Double-Layer Orthogonal-Offset Platforms in fluid and insolation environments." Phd thesis, 2018. http://hdl.handle.net/1885/141393.

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The DLOOP is a structure of non-overlapping tiles (typically corner connected) occupying two layers. Interest in the DLOOP arises from Photo-Voltaic (PV) tracking applications. The tiles (PV modules) of contemporary tracking systems are within one contiguous layer, i.e. a side-by-side platform (SSP). Trees collect solar energy using branching structures to support leaves which are, similar to PV modules, planar surfaces of solar energy transformation. The tree's form is naturally excellent for lowering structural stress in limbs and thermal stress in leaves. For analogous reasons, related to the creation of flow paths that would otherwise be blocked, this research hypothesised (and has subsequently shown) that: * the fluid (wind) dynamic force on tiles of high inclination SSP may be reduced (up to 30%) adopting DLOOP arrangements; and * the temperature of heated tiles in SSP may be reduced (up to 5K within nominal and hot terrestrial environments), by passive convective cooling, adopting DLOOP arrangements. Fluid (wind) dynamic force is significant in PV applications because it typically exceeds the force of gravity on the tiles of SSP in 13m/s winds and increases with velocity squared. Hence reducing wind force by 30% should allow 40% more tiles to be fitted to contemporary tracking mechanisms. Temperature is significant in PV applications because the performance of PV tiles typically falls 0.4%/K. Hence a 5K reduction in temperature should improve efficiency 2%. A combination of wind-tunnel tests, Particle Image Velocimetry and Computational Fluid Dynamic (CFD) simulations using Reynolds Averaged Navier Stokes and Large Eddy Simulation turbulence models was used for the fluid dynamic research. A combined Finite Element/CFD simulation of PV panels in platforms was developed to model temperature outcomes of thermal diffusion in solid materials and thermal diffusion, radiation and convection in the fluid (air). If PV-tracking ranges are limited below those of the solar-vector, shading of the DLOOP lower by the upper layer occurs. This DLOOP self-shading raises unique cost-benefits associated with tracking ranges. Consequently, this research develops a means to quantify the insolation received by platforms accounting for technology and tracking range in diverse (Australian) climates. Additionally, multiple tracking platforms may be placed in close proximity and suffer "Parasitic" energy losses when shaded by self-similar neighbours. Therefore, this research study introduces a natural no-shade scale to describe and optimise field layouts according to local insolation and economic conditions.

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Dissertations / Theses on the topic 'Insolation'

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