In non-residential buildings, comfort and energy demand for heating, cooling and lighting are significantly influenced by the façade. Up to now, only non-weighted luminance-based methods for calculating and evaluating annual daylight glare exist (Lee et al., 2005; Mardaljevic and Lomas., 1998). Within this paper, different methods based on the daylight glare probability DGP (Wienold and Christo...

The apparent color of an object within a scene depends on the spectrum of the light illuminating the object. However, recording an object's color independent of the illuminant spectrum is important in many machine vision applications. In this paper the performance of a blackbody-model-based color constancy algorithm that requires four sensors with different spectral responses is investigated un...

COLOR-BASED MODELS FOR OUTDOOR MACHINE VISION FEBRUARY, 2002 SHASHI D. BULUSWAR, B.A., GOSHEN COLLEGE M.S., UNIVERSITY OF MASSACHUSETTS AMHERST Ph.D., UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor Allen R. Hanson This study develops models for illumination and surface reflectance for use in outdoor color vision, and in particular for predicting the color of surfaces under outdoor c...

Linear models have already been proved accurate enough to recover spectral functions. We have resorted to such linear models to recover spectral daylight with the response of no more than a few real sensors. We performed an exhaustive search to obtain the best set of Gaussian sensors with a combination of optimum spectral position and bandwidth. We also examined to what extent the accuracy of d...

BACKGROUND In bright light, mammals use a distinct photopigment (melanopsin) to measure irradiance for centrally mediated responses such as circadian entrainment. We aimed to determine whether the information generated by melanopsin is also used by the visual system as a signal for light adaptation. To this end, we compared retinal and thalamic responses to a range of artificial and natural vis...

This study investigates the daylighting and thermal performance of open-plan office buildings with two scenarios of daylight louvers – fixed and motorized ones. Both types are for facade window applications. They redirect transmitted daylight to eliminate glare on occupants and increase daylight levels deeper in the interior space, but have significantly different daylight transmitting characte...

BACKGROUND Daylight saving time affects millions of people annually but its impacts are still widely unknown. Sleep deprivation and the change of circadian rhythm can trigger mental illness and cause higher accident rates. Transitions into and out of daylight saving time changes the circadian rhythm and may cause sleep deprivation. Thus it seems plausible that the prevalence of accidents and/or...

This paper presents a fast algorithm for daylight simulation and analysis of complex architectural environments that considers both direct sunlight and diffuse daylight. Shadow determination is performed using a combination of parallel projection and ray tracing techniques. Parallel projection provides execution times that are linear with respect to the number of polygonal objects in the enviro...