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This paper investigates the impact of transmittance level and layout variations of semi-transparent photovoltaics (STPV) on both energy performance and occupancy-based visual and thermal comfort, simulating a reference office with a fully south-oriented glazed surface. Four transmittance levels (20, 30, 40 and 50%) were investigated, first uniformly distributed on the full glazing (i.e., one specific transmittance for the entire glazing) and then considered in combination (i.e., with the glazing divided in equal-height bands with different transmittance levels). Simulations were conducted in three climatic conditions: temperate (Geneva), hot-arid (Casablanca) and cold (Helsinki). Following the proposed energy and occupancy-based visual and thermal comfort analysis, the best design option for both Geneva and Helsinki climate resulted the 2-level STPV design variation with 50% visible transmittance on top of the glazing. In Casablanca, the 1-level design variation with the lowest visible transmittance (20%) uniformly distributed resulted as the best choice. This work, besides offering a first exploration of the relationships between climatic context and STPV design variations, describes a spatial multi-criteria analysis method that could be applied for the evaluation of other glazing technologies.

Designing the buildings that facilitate optimum utilization of daylight is desirable for its many benefits [1], [2] yet challenging due to other intrinsic properties of daylight responsible for over-heating and discomfort glare [3]. Discomfort glare has been studied for several decades, although current empirical glare models are unable to account for the inter-individual differences in glare perception[4]. The complex and multidisciplinary nature of the phenomenon involves the fields of ophthalmology, lighting engineering, neuroscience but these fields remain quite disconnected from one another, which further adds to the slow progress in understanding this phenomenon [5], [6]. It is, therefore, necessary to incorporate interdisciplinary approach to anticipate what creates or influences the perception of discomfort glare from daylight. We aim to contribute to furthering this understanding by evaluating the discomfort glare perceived by the users in relation to eye morphology, with a dedicated focus on the macular pigment (MP) in the retina (Figure 1), an ocular characteristics shown to influence visual performance [4]. Figure

In industrialized countries, people spend on average 85-90% of their time indoors (1). For this reason, major efforts are being made to understand and control the factors which affect people’s comfort, health and well-being inside buildings (2). The indoor environmental quality is characterized by four main parameters, i.e., indoor air quality, acoustic ambience, visual and thermal conditions. The human senses allow people to perceive the environment and estimate their comfort and acceptability with respect to these four indoor environmental factors. For this reason, the evaluation of indoor comfort requires a thorough understanding of how humans (intended as beings characterised by a body and mind) perceive and respond to these environmental parameters (3). Over the last century, studies have considered only one single factor at a time of the indoor environment with the aim to identify relationships between the single component and human comfort. These studies resulted in comfort models (e.g., thermal comfort) (4), standards, guidelines (5–8) and quantitative indices (9) which provided threshold values for light, temperature, noise and air quality. Current building design and technologies devoted to control the indoor environment are designed on supposedly independent effects of visual, thermal and other factors (10). Yet, human sensory systems are not modular, but integrate and respond to environmental factors simultaneously. Moreover, such environmental factors commonly occur in combination. It becomes clear that no single parameter of the indoor environment can be evaluated on its own. Thus, to improve our understanding of the influence of environmental parameters on human responses and perceptions in indoor environments, it is necessary to study their combined effects. Predicting the integral building performance in terms of comfort is a complex task. For this reason, to progress with global comfort knowledge it is necessary to start with the study of the interactions of two factors at a time (11). This Ph.D. research focuses on the interaction between visual and thermal stimuli on comfort perception and performance by means of experiments in an office-like test room in EPFL campus and validation in field studies. In particular, it analyzes the effect of visual variables on the perceived thermal comfort and of thermal variables on the perceived visual comfort, beside their interactive influence on performance. Three different experiments are planned, analyzing the mutual influence of the following parameters on thermal and visual comfort perception: (i) coloured daylight and temperature, (ii) illuminance level and temperature (iii) glare and temperature. The first experiment about the influence of coloured daylight on thermal comfort perception and of temperature on colour acceptability and preference has started in November 2016.

We propose a new method for climate-based daylight modeling (CBDM) based on simulating and evaluating only the most important features. By adaptively sampling the temporal lightfield that describes daylight in buildings, our method escapes the curse of dimensionality that binds typical approaches. The method is centered around an iteratively guided sampling strategy that produces unordered sky and sun coefficient samples throughout an architectural space. This data is organized into a lightfield data structure that can be evaluated under any sky condition. Outputs include photometric quantities, visual comfort metrics, and high dynamic range images. Unlike existing CBDM methods, our approach is not limited by the rendering algorithm, material model, level of detail, or metric output. Our method is accurate and fast. As such it can serve as a general interface for any view or point-based daylighting question, including those answered by illuminance and luminance based metrics.

Occupants’ visual comfort in an indoor space strongly depend on the quantity and quality of the daylight inside the space which can be altered with the type of window glazing. In this study, we compared the visual comfort perception of participants with sun in their field of view under two types of glazing: color-neutral and blue-tinted electrochromic glazing. The main experimental variables are the color and visible light transmittances of the glazing. The aim was to determine the influence of these variables on participants’ discomfort glare, view out and color perception. We found that the discomfort glare was perceived more strongly with blue-tinted glazing compared to the color-neutral glazing for a range of (low) transmittances. We also found that the colors of outdoor elements were rated non-natural in case of blue-tinted glazing compared to color-neutral glazing. The outside view was perceived more restricted in blue-tined glazing compared to color-neutral glazing even though both of them maintain view clarity.

A well daylighted space can provide a highly satisfying visual environment. However, if that environment causes us visual discomfort, it can become such a nuisance that we, sometimes literally, turn our backs on this powerful connection to the outside world. Given this, there is enormous value in quantifying the occurrence of discomfort glare within buildings, and in glare models that may guide architects and engineers in design. With the success of climate-based modeling techniques for daylight illuminance, there is now a focus on including discomfort glare metrics in spatio-temporal evaluations. This article conducts a literature review of research focused on spatio-temporal simulations for glare assessment. Studies are reviewed according to their objectives, metrics calculated, spatial scope, temporal scope and scene variety. The goal is to document the limitations of current simulation methods, the potential to generally apply these methods, and how well these methods incorporate empirical glare research. This review finds that, due to computational constraints, there is an over-reliance on illuminance-based metrics for spatio-temporal glare assessment, even while user assessment research reinforces the importance of including contrast-based measures. To achieve an accurate zonal glare assessment, future research should focus on improving simulation efficiency and identifying ways to reduce the spatial, temporal and angular scope of the simulation, while maintaining high accuracy., SDAR Journal of Sustainable Design in Engineering of the Built Environment, 7 (1)

Within the scope of a broader research project about visual and thermal interaction effects on human comfort and perception, the aim of this paper is to study the variation of thermal, visual and overall comfort votes of people exposed to blue and orange glazing. The study, conducted in a controlled test room and involving a total of 75 participants, is repeated at three temperature levels to investigate whether variations in comfort votes are affected by the thermal environment. Results show that participants changed their comfort votes for both thermal and overall comfort, beside the expected visual comfort, due to changes in glazing colour. Larger variations in thermal and overall comfort votes are observed in the close-to-comfortable temperature range (22 °C). Temperature-related effects can be seen for visual and thermal comfort evaluations. Overall comfort shows a positive correlation with both visual and thermal comfort.

To understand how daylight gives shape and life to architectural spaces, whether existing or imagined, requires quantifying its dynamism and energy. Maintaining these details presents a challenge to simulation and analysis methods that flatten data into discrete images or virtual sensor points from a point and time. To address this challenge, this thesis presents a new method for sampling and evaluating simulated daylight. It is intended as a bridge between image-based and sensor-based methods; one that can produce image-level high accuracy directional distribution data with much shorter simulation times that are closer to sensor-based methods. Instead of producing a fixed grid of points, pixels, and sun directions, an iteratively guided sampling approach structured by the discrete wavelet transformation captures the distribution of light incident on a viewpoint with a variable density. By storing the direction vector and effective solid-angle of each sampled ray, the data can be directly evaluated for any luminance-based quantity and view direction. Coupled with daylight coefficients, where the contributions from regions of the sky-dome are recorded rather than associating a value to every possible sky distribution, these methods reduce simulation time at three stages by reducing the number of samples. With fewer samples, it takes less time to render, less time to combine with sky values, and less time to evaluate potential glare sources. Through a series of simulated reference validations, this thesis shows that the proposed method can reproduce the value predicted by a high quality reference simulation in a small fraction of the time. The method achieves higher accuracy results compared to those of existing simulation methods that rely on simplifications. The method is robust across a wide range of daylight conditions and can be tuned to the desired scope of the output. The method can be applied to render a single image in high detail or used to calculate glare metrics in order to evaluate a whole building zone. This method enables a more complete characterization of daylight and visual comfort across an occupied zone; one that is less biased by proxy measurements, representative point selection, or assumptions about glare-causing pathways. Using these methods, we can more reliably understand how daylight will respond to proposed interventions, which should be useful for guiding design, regulatory standards, and improving performance.

Avoiding discomfort glare is one of the critical aspects of maintaining visual comfort, which significantly influences occupants' overall satisfaction with their indoor environment. Discomfort glare prediction models have been developed for various lighting conditions, and their equations commonly use either contrast and/or saturation terms to account for glare caused by excessive luminance contrast or excessive overall brightness, respectively. Daylight Glare Probability (DGP), which includes both terms (hybrid model) and thus accounts for both effects, is one of the more robust ones. However, the predictive performance of discomfort glare models is limited to the luminous conditions and light source types found in the dataset from which they were developed. As daylight glare models like DGP are typically derived from glare evaluations in brightly lit environments, their performance in dimmer conditions, such as those found in deep open-plan workspaces away from the window, could be limited. This thesis, therefore, aims to extend the prediction range of existing discomfort glare models to reliably cover low-light ranges as well. To determine which conditions are most critical to focus on, the luminous ranges covered in previous laboratory studies were compared to those that can be expected in open-plan offices where low-light conditions may occur. The identified range of missing lighting conditions was then used to design and conduct two new user studies in semi-controlled dim daylit conditions to supplement prior discomfort glare datasets. In the first study, participants evaluated four scenes in which the size and luminance of the glare source were varied, and in the second, participants evaluated four scenes in which it was the size and position of the glare source were varied. In parallel, the models that currently perform best in dimmer conditions were identified using an existing dataset of glare evaluations in daylit conditions: contrast-driven models were shown to outperform saturation-driven models in dim conditions, while the more versatile hybrid metrics tended to perform well overall. Hence, the hybrid format was found to be better suited for extending glare models. To create a comprehensive training dataset for this model extension, the data obtained from the two user studies were combined with experimental data from other recent studies containing high-contrast scenarios, namely with the sun disc visible through fabric shadings and low-transmittance glazing. A new best-fit discomfort glare prediction model was then proposed for the broader targeted range of luminous conditions. Based on preliminary performance checks, the new hybrid model appears to fit the participants' glare responses better in low-light conditions than the reference model, DGP, while maintaining a fit equivalent to DGP in brightly lit conditions. The new user studies also revealed an unexpected finding: the summation of multiple glare sources in glare model equations can sometimes result in an over-prediction of discomfort glare. More research will be needed to validate the newly proposed model using a larger test dataset that does not include data points used for any model development. This thesis' findings may help to advance daylight glare prediction in indoor spaces by broadening the range of validity of prediction models to dimmer conditions, thus improving the overall reliability of visual comfort appraisal in the built environment.

Over the past years, increasing efforts have been devoted to understand how people perceive the indoor environment with the goal to improve building design and operation. Studies have separately addressed the effects of the four main aspects that influence the perception of the indoor environment, i.e., visual appearance, thermal condition, acoustic ambiance, and air quality. However, building occupants are simultaneously exposed to multiple indoor stimuli and their perception of the indoor environment depends on the mutual combination and interaction of such stimuli. Despite the increasing interest in the topic, few studies on the interactions between indoor factors are available. Most of them have focused on interactions between thermal and visual factors due to their large implications for energy consumption and building design. In this context, electric lighting has been primarily used as visual stimulus, leaving a knowledge gap on interaction effects in daylit environments. To address this challenge, this doctoral thesis focuses on the effects of visual and thermal interactions on human responses, with the use of daylight as the sole source of light. Two types of visual-thermal combinations are investigated: temperature and "daylight color" (i.e., daylight transmitted through colored glazing) and temperature and daylight quantity (i.e., illuminance levels). The aim of this work is threefold: (i) understand the effect of daylight color and quantity on thermal perceptual and physiological responses; (ii) investigate the influence of indoor temperature on visual perception of daylight; and (iii) explore the effect of daylight and temperature combination on the overall comfort perception. To address the previous aspects, four experiments were conducted. Two of them were carried out in an office-like test room to investigate both visual-thermal combinations. One field study was performed to further explore temperature and daylight quantity interactions. One experiment was conducted in a test room with the use of virtual reality to further investigate temperature and "daylight color" interactions. The results of this thesis show that daylight and temperature do interact, influencing human responses in a perceptual rather than in a physiological way. The interaction effects are bi-directional, as temperature influences visual perception, and daylight color and quantity affects thermal perception. Daylight conditions and indoor temperatures simultaneously and equally contribute to the overall comfort perception, but only after a relatively long exposure to the visual stimulus. The findings of this research suggest that indoor factors should not be considered separately but in combination. The integration in both research and practice of interaction effects between indoor factors will ultimately contribute to the improvement of comfort conditions inside buildings. Potentially, this integration will also allow to reduce the energy consumed in buildings to guarantee occupants' comfort due to the extension of the comfort ranges that currently neglect interaction effects between indoor environmental factors. Disentangling for the first time the complex relationship between daylight and indoor temperature, this research constitutes an additional step towards understanding interactions of indoor factors and contributes to the establishment of a comfortable and energy-efficient built environment.

Exposure to light, and especially to daylight, has much to offer. Regarding buildings’ occupants, daylight has been shown to boost performance, improve sleep, provide a connection to the outside, increase comfort, lessen agitation, and reduce depression. Regarding buildings, daylight enhances the aesthetics of a space and improves its energy efficiency. On one condition, though: that it does not produce visual discomfort. In order to harvest the benefits of daylight, visual discomfort has to be minimized. Hence, discomfort glare from daylight should be predictable. To date, more than twenty daylight discomfort glare models have been developed. However, none of them can consistently and accurately explain the large variation between subjects’ discomfort glare perception. Improving current models predicting discomfort glare perception remains a crucial step to move towards optimal daylighting design in buildings. In this context, it is hypothesized that the prediction of discomfort glare perception can be improved by including relevant additional factors related to the context or to the subject in the models. The main research question that this study aims to answer is to determine whether one of these factors, namely the socio-environmental context of the subject, influences discomfort glare perception from daylight in office buildings. The socio-environmental context is defined here as the climate and habitat, including indoors and outdoors, to which a subject has been acclimatized, her/his behavior toward these elements, and her/his expectations about them. Two additional research questions aim at investigating other potentially influencing factors and potential experimental biases in order to guide further research in the field. For this purpose, a field study was conducted in real office buildings located in four socio-environmental contexts, i.e., Chile, Belgium, Japan, and Switzerland. Discomfort glare perception evaluations, each consisting of a subjective assessment of discomfort glare from daylight and the measurement of the visual stimulus, were collected at the office desk of the 401 subjects who took part in the study. The raw data was processed to derive useful information, and cleansed according to specific rules to ensure data quality. Different statistical analyses were conducted on the processed and cleansed data to answer the main research question. No statistically significant differences in the sensitivity to discomfort glare from daylight could be observed between the subjects acclimatized to the Chilean, Belgian, Japanese, and Swiss contexts. The results show therefore no evidence of an influence of the socio-environmental context of a subject on discomfort glare perception from daylight in office buildings. Furthermore, the influence of several other factors on discomfort glare perception from daylight in office buildings was tested and the data was further analyzed regarding potential experimental biases in order to answer the two additional research questions. A statistically significant effect was found for three factors, namely the self-assessed glare sensitivity, the attractiveness of the view through the window, and the indoor air temperature. From this result, it can be hypothesized that these factors could influence discomfort glare perception. Moreover, further analyses suggest that two experimental biases, namely the glare rating scales and the study type, could be influencing the results of studies on discomfort glare perception. However, since the study was not specifically designed to answer these two additional research questions, and in view of its limitations, no conclusion can be drawn on these last observations. They can, however, be used to guide the development of future studies. In conclusion, this research provides no evidence that discomfort glare from daylight is perceived differently in different socio-environmental contexts. Research efforts in discomfort glare perception from daylight should therefore aim at improving prediction models by looking at other potential factors, such as physiological and environmental ones. Finally, future studies should also aim for the validation of reliable methods to study discomfort glare, and for the development of a unified methodological framework to promote the reproducibility of studies and the comparability of results. L’exposition à la lumière, et en particulier à la lumière du jour, a beaucoup à offrir. En ce qui concerne les occupants des bâtiments, il a été démontré que la lumière du jour accroît les performances, améliore le sommeil, assure une connexion avec l’extérieur, augmente le confort, diminue l’agitation et réduit la dépression. En ce qui concerne les bâtiments, la lumière du jour met en valeur l’esthétique d’un espace et améliore son efficacité énergétique. Cela n’est valide qu’à une condition cependant : qu’elle ne produise pas d’inconfort visuel. Afin de récolter les bénéfices de la lumière du jour, l’inconfort visuel doit être minimisé. Par conséquent, l’éblouissement d’inconfort causé par la lumière du jour devrait être prévisible. À ce jour, plus de vingt modèles d’éblouissement d’inconfort dû à la lumière du jour ont été développés. Cependant, aucun d’entre eux ne peut expliquer de manière cohérente et précise la grande variation de la perception de l’éblouissement d’inconfort d’un sujet à l’autre. L’amélioration des modèles actuels permettant de prédire la perception de l’éblouissement d’inconfort demeure une étape cruciale afin d’avancer vers une conception optimale de l’éclairage naturel dans les bâtiments. Dans ce contexte, nous émettons l’hypothèse que la prédiction de la perception de l’éblouissement d’inconfort peut être améliorée en incluant dans les modèles des facteurs additionnels pertinents liés au contexte ou au sujet. La principale question de recherche à laquelle cette étude cherche à répondre est de déterminer si l’un de ces facteurs, à savoir le contexte socio-environnemental du sujet, influence la perception de l’éblouissement d’inconfort par la lumière du jour dans les immeubles de bureaux. Le contexte socio-environnemental est défini ici comme le climat et l’habitat, en ce compris l’intérieur et l’extérieur, auxquels un sujet s’est acclimaté, son comportement envers ces éléments, et ses attentes à leur égard. Deux questions de recherche supplémentaires visent à étudier d’autres facteurs potentiellement influents, ainsi que d’éventuels biais expérimentaux, afin d’orienter la recherche future dans ce domaine. À cette fin, une étude de terrain a été menée dans des immeubles de bureaux situés dans quatre contextes socio-environnementaux différents, à savoir au Chili, en Belgique, au Japon et en Suisse. Les évaluations de la perception de l’éblouissement d’inconfort, consistant chacune en une évaluation subjective de l’éblouissement d’inconfort causé par la lumière du jour et en la mesure du stimulus visuel, ont été collectées aux bureaux des 401 sujets qui ont participé à l’étude. Les données brutes ont été traitées pour en tirer les informations nécessaires et nettoyées selon des règles spécifiques pour en assurer la qualité. Différentes analyses statistiques ont été effectuées sur les données traitées et nettoyées pour répondre à la principale question de recherche. Aucune différence statistiquement significative de la sensibilité à l’éblouissement d’inconfort dû à la lumière du jour n’a pu être observée entre les sujets acclimatés aux contextes chilien, belge, japonais et suisse. Les résultats ne montrent donc aucune preuve d’une influence du contexte socio-environnemental sur la perception de l’éblouissement d’inconfort par la lumière du jour dans les immeubles de bureaux. De plus, l’influence de plusieurs autres facteurs sur la perception de l’éblouissement d’inconfort dû à la lumière du jour dans les immeubles de bureaux a également été testée et les données ont été analysées plus en détails par rapport aux potentiels biais expérimentaux afin de répondre aux deux questions de recherche supplémentaires. Un effet statistiquement significatif a été constaté pour trois facteurs, à savoir la sensibilité à l’éblouissement auto-évaluée, l’attrait de la vue à travers la fenêtre et la température de l’air intérieur. Une hypothèse peut être émise à partir de ces résultats : ces facteurs pourraient influencer la perception de l’éblouissement d’inconfort. Des analyses additionnelles suggèrent que deux biais expérimentaux, à savoir les échelles d’évaluation de l’éblouissement et le type d’étude, pourraient influencer les résultats des études sur la perception de l’éblouissement d’inconfort. Toutefois, comme cette étude n’a pas été spécifiquement conçue pour répondre à ces deux questions de recherche supplémentaires, et compte tenu de ses limitations, aucune conclusion ne peut être tirée de ces dernières observations. Les hypothèses émises peuvent toutefois servir à orienter l’élaboration d’études futures. En conclusion, cette recherche ne fournit aucune preuve que l’éblouissement d’inconfort causé par la lumière du jour est perçu différemment dans différents contextes socio-environnementaux. Les efforts de recherche sur la perception de l’éblouissement d’inconfort dû à la lumière du jour devraient donc se concentrer sur l’amélioration des modèles de prédiction en examinant d’autres facteurs potentiels, tels que les facteurs physiologiques et environnementaux. Enfin, les études futures devraient également viser à valider des méthodes fiables pour l’étude de l’éblouissement d’inconfort, ainsi qu’à élaborer un cadre méthodologique homogénéisé pour promouvoir la reproductibilité des études et la comparabilité des résultats. (FSA - Sciences de l'ingénieur) -- UCL, 2019

Spectrum and correlated colour temperature of light are shown to influence human visual comfort. Previous research conducted with electric light, mainly in the context of vehicular headlamps, have demonstrated that coloured LEDs induce more discomfort glare than white LED and among the coloured LEDs blue ones gave the highest glare perception[1]–[3]. However, there are currently no studies that determine the influence of filtered daylight on discomfort glare in context of daylit indoor spaces which can prove valuable for building façade industry. The spectral power distribution of the daylight inside a space can vary depending on the glazing spectrum. With the current trend of tinted glazing such as electrochromic (EC) glazing and dye-sensitized solar cell glazing that alters the spectrum of daylight, there is a need to extend these results under daylit conditions. To address this gap, we conducted a between subject study investigating the effect of glazing color on occupants’ glare perception under blue-tinted EC glazing (20 participants) and color-neutral glazing systems (55 participants), both widely employed in commercial buildings. We exposed the participants to four visual scenarios with different low glazing transmittances and the sun as the only glare source visible through the glazing. The tests were conducted in a semi-controlled office-like test room with daylight as the only source of light. The glazing’s spectral transmittances were experimentally determined in a dedicated glazing and nanotechnology lab facility. During the exposure time, participants were given a typing task that allowed them to visually adapt to each experimental scenario. Afterwards, participants filled a questionnaire indicating their level of visual comfort. We captured high dynamic range images of each experimental scenario from participant’s eye position to record the scene luminance and calculate various daylight glare metrics. Comparing participant’s responses to glare, we found that through color-neutral glazing of various transmittances, the reported level of discomfort was similar to EC glazing for twice the sun disc’s luminance, thereby indicating that glare was perceived stronger for a blue-colored glare source. This outcome questions whether we measure the luminance and glazing transmittance correctly under tinted glazing scenarios, since the standard way of measuring photometric quantities uses the CIE V2() function for 2-degree standard observer but falls short of explaining the enhanced glare sensitivity under shorter wavelengths. To further delve into this question, we applied the standard CIE V10() sensitivity curve along with earlier proposed luminous efficiency functions for discomfort glare and compared them in terms of their ability to account for differences in the perceived discomfort glare. The results showed that none of these luminous efficiency functions can explain the increased sensitivity for blue-colored glare source that was found, which indicated that its cause should be sought elsewhere. Based on the results, we provide recommendations towards the transmission thresholds for switchable glazing to prevent glare risks when sun is in the field of view. Outcomes of this study can be further implemented to the future development goals for switchable glazing systems and architectural façade design application in achieving visually comfortable spaces. References: [1] Y. Yang, R. M. Luo, and W. Huang, “Assessing glare, Part 3: Glare sources having different colours,” Lighting Research & Technology, vol. 50, no. 4, pp. 596–615, Jun. 2018, doi: 10.1177/1477153516676640. [2] M. Sivak, B. Schoettle, T. Minoda, and M. J. Flannagan, “Short-Wavelength Content of LED Headlamps and Discomfort Glare,” The Journal of the Illuminating Engineering Society, vol. 2, pp. 145–154, 2005, doi: 10.1582/LEUKOS.2005.02.02.006. [3] J. Fekete, C. Sik-Lányi, and J. Schanda, “Spectral discomfort glare sensitivity investigations,” Ophthalmic and Physiological Optics, vol. 30, no. 2, pp. 182–187, Mar. 2010, doi: 10.1111/j.1475-1313.2009.00696.x.

Ongoing method development for adaptive spatio-temporal sampling in light simulation for zonal glare assessments., This research is funded by the Swiss National Science Foundation SNSF under grant #179067 as part of the project "Light fields in climate-based daylight modeling for spatio-temporal glare assessment" (http://p3.snf.ch/project-179067).