M.Ing. / The focus of the document is the development and use of an algorithm that controls a heliostat, and the high level design of that heliostat. The heliostat is only controlled by the algorithm and had a specified accuracy requirement equal to or better than 0.5 degrees. The algorithm uses the elevation and azimuth angle of sun calculated to an accuracy of 0.0003 degrees as input. The algorithm positions the heliostat to ensure a continuous reflection of sunlight into a predetermined direction for the purpose of indoor illumination. The position of the sunlight reflected into the predetermined direction is marked on a vertical grid-board placed orthogonal to the intended reflection direction. Ideally the sunlight positions marked throughout the day will all be in one location. The reflected sunlight deviated from the intended direction by only 0.28 degrees.

This thesis presents laboratory and field studies into the effects of solar radiation on the thermal comfort of vehicle occupants. Whilst, thermal comfort has been widely studied in built environments, there have been relatively few studies into thermal comfort in vehicles. Those studies that have been conducted have noted that the effect of solar radiation is considerable in these confined microclimates. The aim of this thesis was to provide baseline data for the effects of solar radiation on thermal sensation and determine how this information can be integrated to provide a method for the assessment of vehicle thermal comfort. This was achieved using a specially constructed whole body solar chamber in a series of four laboratory studies looking at different aspects of solar radiation on human thermal comfort and an extensive field trial conducted in Seville, Spain. The laboratory studies were as follows:- 1, The effect of the intensity of direct simulated solar radiation on human thermal responses. Eight male subjects were exposed to 4 different intensity solar radiation conditions. Physiological and psychological measurements were taken. It was established that a mean response to 200 Wm"2 of direct simulated solar radiation will give a thermal sensation shift of one positive scale point. 2, The effect of the spectral content of simulated solar radiation on human thermal responses. Eight male subjects were exposed to 4 different spectral radiation conditions, with the same total radiation intensity, 400 wm·2 • There was found to be no significant difference in the thermal sensation responses due to spectra. 3, The effects of glazing type on human thermal comfort responses. Eight male subjects were exposed to 4 different automotive glazings, with a fixed external solar radiation level of 1000 wm·2 • The spectral qualities of glazing can significantly effect human thermal comfort. The lower the transmission of visible radiation through the glazing, the lower the thermal sensation felt by subject in a neutral environment. 4, The effect of direct short wavelength and long wavelength radiation on human thermal comfort. Nine male subjects were exposed to short wavelength, long wavelength and combined short and long wavelength radiation. For the conditions investigated it was established that the addition of reradiation from internal components has an effect on thermal sensation when combined with direct solar radiation. However, it is not considered that it will be a major factor in a real world situation, as dashboards generally do not maintain high surface temperatures in vehicles without high air temperatures. Using the data collected in the laboratory studies a predictive model, PMV sotu, was developed which integrated directed solar radiation into an existing thermal comfort model (PMV) in the form of a factor, Rsolar· Rsolar is a correction factor for the addition of short wavelength radiation which converts actual measured solar radiation to a thermal sensation scale adjustment The PMV solar model was validated with other models in field trials conducted in Seville, Spain. Four male subjects, undertook a series of 32, one hour long experiments over 8 days, whilst travelling on a Spanish highway. Environmental, physiological and psychological measurements were taken throughout the experiments to provide data for validation of THE PMV solar model. The assessment of human thermal comfort in vehicles is complex. Variation in environmental parameters in terms of both spatial and temporal changes, make accurate prediction of thermal comfort difficult. However, the PMV solar model provides an improved level of prediction of the state of thermal comfort of the vehicle occupants, in environments which have a high solar radiation level over existing thermal indices.

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

The performance of three models which use satellite data to estimate solar irradiance at the Earth's surface is assessed using measured radiation data from a mid-latitude location. In addition the mesoscale spatial variability in the global solar irradiance resolvable by the three models is also evaluated. The data are drawn from a twelve station pyranometric network and represent a variety of sky conditions at different times of the year. Assessment of the models depends upon the accurate Earth location of the satellite imagery and the merging of satellite and pyranometric data. The resolution of the satellite data for the study area is determined to be 0.82 km in the East-West direction and 1.67 km in the North-South direction. Based on this resolution the satellite imagery can be Earth located to within 1.25 km in an East-West direction and to within 1.71 km in a North-South direction. Merging of the satellite and pyranometric data results in the use of as many as three images to represent the radiation characteristics of a given hour. Initial applications of the three models reveal that the original regression coefficients for both the Tarpley (1979) and Hay and Hanson (1978) models are inappropriate for the study area because of the bias introduced. Subsequent revision of these coefficients leads to significant improvements under most conditions. Seasonal assessments of the three models demonstrate that on an hourly basis the overall performance of the Gautier et al. (1980) model under partly cloudy and overcast conditions is superior to that of the other two models. However, compared to the clear sky case all three models give poor results under partly cloudy and overcast conditions. An increase in the averaging period leads to marked decreases in the RMS errors observed for the three models under all conditions with the greatest improvement occurring for the Hay and Hanson (1978) model. Changes in temporal and spatial averaging configurations reveal that temporal averaging could have an important influence on the radiation estimates under partly cloudy and overcast conditions. Spatial averaging in the context of the Gautier et al. (1980) model does not support the use of an 8 x 8 pixel array to improve the temporal representation of the satellite data. In terms of the mesoscale spatial variability in the global solar irradiance, the best resolution is provided by the Gautier et al. (1980) model. For hourly values an average RMS error of ±17.1% limits the spatial resolution to approximately 15 km; for daily values an average RMS error of 8.2% limits the spatial resolution to approximately 12 km. Suggestions for improvements in the three models include; 1) a more accurate and explicit treatment of cloud absorption; 2) the consideration of the effects of changing Sun-satellite azimuth angle under overcast conditions and 3) in the context of both the Gautier et al . (1980) and Tarpley (1979) models there is the need for the inclusion of the effects of aerosols under clear skies and the accurate and objective specification of a cloud threshold. / Arts, Faculty of / Geography, Department of / Graduate

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No description available.

<p> An investigation of the effects of cumulus clouds on solar radiation was carried out during the 1977 field season at McMaster University, Hamilton. The measurement of total incoming solar radiation, direct beam radiation and the diffuse flux calculated as a residual, were used to draw inferences regarding the transmission properties of cumulus clouds, both on a daily basis and for different cloud fields, The diffuse flux, showing the greatest variability, was sub-divided into three components and each were evaluated under unobscured and obscured sun conditions. Measured values were compared with those derived for a model atmosphere.</p> / Thesis / Bachelor of Arts (BA)

Entomopathogenic fungi are highly susceptible to the damaging effects of solar radiation. Attempts to protect entomopathogenic fungi from solar radiation have been, for the most part, unsuccessful. A new strategy for formulating entomopathogenic fungi for protection from solar radiation and desiccation has been developed tested using the acridid entomopathogen Metarhizium anisopliae var acridum (IMI 330189). This strategy involves coating spores with water-soluble materials that provide protection from solar radiation and enhance spore survival during drying. Development of this formulation involved the following: 1) production of an infective spore-type in liquid culture that could survive drying; 2) coating spores during an air-drying process; 3) reducing formulation particle size for oil suspension; 4) testing the effects spore coating on spore-tolerance simulated sunlight; and 6) testing the effects of spore coating infectivity to Schistocerca americana. Aerial conidia, submerged conidia, and blastospores produced in a high-osmolality liquid medium all had high desiccation tolerance relative to blastospores produced in Adamek's media. Blastospores produced in high osmolality medium were the most infective to S. americana in an aqueous 20% molasses solution followed by submerged conidia and aerial conidia, with LT50 values (95% C.I.) at 1 x 106 spores/insect of 7.8 d (6.7 to 9.0 d), 10.5 d (9.5 to 11.6 d), 14.6 d (11.9 to 18.0 d), respectively. Comparisons were made among cell-wall characteristics of these spore-types, including cell-wall thickness, lectin-binding, charge, and hydrophobicity. An optimal spore-coating formulation was selected on the basis of spore survival and germination over time after air-drying, particle-size reduction, and storage at 28 Ë C. This spore-coating formulation, consisting of skim milk, Kraft lignin (Curan 10®) and glycerol, greatly improved the tolerance of aerial conidia and submerged conidia to simulated sunlight, increasing the LT50 (95% C.I.) of aerial conidia from 4.0 hr (3.1-5.1) to 17.0 hr (12.5-23.0). The spore coating formulation decreased the infectivity of spores in oil to adult S. americana; reducing the LT50 values of aerial conidia at a dose of 1 x 105 spores / insect from 5.8 d (4.9-6.9 d) to 8.2 d (7.3-9.3 d). / Ph. D.

<p> Simultaneous solar radiation and meteorological observations were taken from an instrumented tower located in southwestern Lake Ontario. During the four month period of this study (July-November, 1969) it was found that short-term fluxes of incoming global radiation could be predicted with a standard error which was better than 0.05 cal cm^-2min^-1 under cloudless conditions. Under cloudy conditions the lowest standard of prediction error (0.14 cal cm^-2min^-1) was obtained using a model which takes into account cloud type transmission. Under cloudless conditions the Fresnel curve underpredicts the albedos observed for low zenith angles and overpredicts when the zenith angle is high. This is mostly due to a backscatter effect estimated to be between 1.5 to 2% and to the albedo of diffuse radiation which was confirmed to be 6.5 to 7%.</p> / Thesis / Master of Science (MSc)

<p> A previous study (Davies and Hay, 1978) described a method of calculating hourly and daily values of global solar radiation for cloudless and cloudy sky conditions. This scheme, requiring only upper air data from daily radiosonde ascents, and hourly surface weather observations, has been used successfully at a number of mid latitude sites (Davies et al., 1975; Suckling and Hay, 1976). In this investigation the extension of this method for use in an Arctic environment is presented. </p> <p> Solar radiation received at the earth's surface is the sum of direct and diffuse components. The flux in cloudless conditions is calculated as the residual after attenuation of solar irradiance by water vapour, ozone, Rayleigh scattering and aerosol. Cloudless sky values are then adjusted for cloud effects, using a cloud layer method similar to that used by Davies et al. in Southern Ontario, Canada. </p> </p> The computed values are compared with values measured at Resolute, N.W.T., Canada. Under cloudless sky conditions hourly and daily calculated values agree well with ·measurements. For days of cloud amount less than 4/10, model overestimates are observed. As cloud amounts increase varying degrees of model underestimation of measured values occur. This is linked with observer inability to adequately specify cloud amount, and the variation of cloud type transmission characteristics for Arctic areas. </p> / Thesis / Bachelor of Arts (BA)