scholarly journals Discomfort Glare Evaluation using DIALux Lighting Simulation software and using developed Python Program model

2018 ◽  
Vol 20 (2) ◽  
pp. 44-50
Author(s):  
Jayashri Aniket Bangali
Keyword(s):  
Bright Light ◽  
Simulation Software ◽  
Visual Sensation ◽  
Light Sources ◽  
Program Model ◽  
Conference Room ◽  
Discomfort Glare ◽  
Lighting Simulation ◽  
Disability Glare ◽  
Comparison Of The Results

Glare is a visual sensation caused by excessive brightness. It is subjective and person dependent. So, it is very difficult to measure glare factor accurately. Glare can be disabling or uncomfortable.  Disability glare is the reduction in vision caused by bright light sources and it can be increased with the age of a person. Discomfort glare is a sensation of irritation due to bright light sources. There are various methods to evaluate discomfort glare. These methods are discussed in this paper. This paper mainly focuses on two methods of discomfort glare evaluation; Unified Glare Rating (UGR) and Daylight Glare Probability (DGP). These glare factors are calculated by using DIALux lighting simulation software and by using developed program. The experimentation was carried out in two different spaces; Conference room and Optoelectronics laboratory. The values of UGR, daylight factor are calculated by using DIALux and developed program. The comparison of the results obtained is discussed at the end of this paper.

Direct illuminance caching: a way to enhance the performance of RADIANCE

2002 ◽  
Vol 34 (4) ◽  
pp. 333-343 ◽  
Author(s):  
Carsten Bauer
Keyword(s):  
Source Code ◽  
Simulation Software ◽  
Light Sources ◽  
Image Generation ◽  
Accurate Calculation ◽  
Software Suite ◽  
Light Component ◽  
Performance Reduction ◽  
Lighting Simulation ◽  
Key Features

The RADIANCE lighting simulation software suite has proven itself a valuable means of producing visualizations and enabling analysis of all kinds of lighting tasks. One of its key features is the accurate calculation of the indirect light component by hemisphere sampling throughout the scene. Currently, there is a certain amount of redundancy within the algorithm. The performance reduction caused by this increases strongly with the number of light sources and becomes significant when more than five sources are present. A method for circumventing this redundancy is presented and its potential for considerably reducing rendering time is shown. The limitations of the new method are discussed and guidelines for its use are given, followed by some remarks on image generation for presentation purposes. The source code of the additional module is provided for downloading.

Analysis of UGR Values and Results of UGR Calculations in Commercial Lighting Simulation Software

2015 ◽  
Vol 11 (3) ◽  
pp. 141-154 ◽  
Author(s):  
A-Rom Son ◽  
In-Tae Kim ◽  
An-Seop Choi ◽  
Min-Ki Sung
Keyword(s):  
Simulation Software ◽  
Lighting Simulation

The Effect of Light on Sleep and Sleep-Related Physiological Factors Among Patients in Healthcare Facilities: A Systematic Review

2019 ◽  
Vol 12 (4) ◽  
pp. 116-141
Author(s):  
Khatereh Hadi ◽  
Jennifer R. Du Bose ◽  
Young-Seon Choi
Keyword(s):  
Light Exposure ◽  
Bright Light ◽  
Light Sources ◽  
Related Factors ◽  
Healthcare Facilities ◽  
New Findings ◽  
Healthcare Environments ◽  
The Impact ◽  
Improve Patient ◽  
Bright Light Exposure

Objectives: Lighting is one of the environmental factors which can improve patient sleep in healthcare environments. Due to the high degree of variation in study designs and results on this topic, the implications have been difficult to interpret. This review consolidates studies on the impact of bright light exposure on sleep to identify lighting conditions that can be applied and researched in future healthcare environments. Methods: We searched for peer-reviewed articles on the impact of light on sleep or sleep-related outcomes in healthcare settings. We provided detailed analysis of the direct links between light and sleep, and a more cursory analysis of links between light and sleep-related factors, from 34 articles which met our inclusion criteria. Results: The current state of the literature includes evidence on how various durations and intensities of morning, midday, and evening bright light exposure, as well as whole-day light exposure interventions can improve specific aspects of sleep. Lighting interventions differed in all attributes (illuminance levels, exposure time, exposure duration, and spectral qualities) but showed promising results in improving patients’ sleep. Conclusions: Short-term bright light exposure in the morning, up to 2 hr of moderate (3,000–10,000 lux) morning exposures, up to 4 hr of moderate evening exposure, and whole-day exposures to lower illuminance levels (<3,000 lux) can improve patient sleep outcomes. Based on new findings on the mechanism through which light impacts sleep, future studies should be more specific about the spectral qualities of light sources.

Subjective and pupil responses to discomfort glare from small, high-luminance light sources

2018 ◽  
Vol 51 (4) ◽  
pp. 592-611 ◽  
Author(s):  
Y Tyukhova ◽  
CE Waters
Keyword(s):  
Pupil Size ◽  
Rating Scale ◽  
Light Sources ◽  
Background Luminance ◽  
High Luminance ◽  
Low Luminance ◽  
Point Rating Scale ◽  
Main Effect ◽  
Discomfort Glare ◽  
Relative Change

This study examined human subjective and pupil responses to small, high-luminance light sources seen against low-luminance backgrounds. Subjective judgements of glare using a seven-point rating scale and the change in pupil diameters following exposure to glare of 47 subjects were measured during evaluation of 36 conditions comprising three glare source luminances (20,000; 205,000; 750,000 cd/m2), two source positions (0°, 10°), two source sizes (10−5, 10−4 sr) and three background luminances (0.03; 0.3; 1 cd/m2). Data analysis suggests that the relative pupil size is correlated with subjective responses to discomfort glare to some extent (r = 0.659). Analysis of variance of relative pupil size measurements demonstrates a significant main effect of the background luminance suggesting that when the background luminance decreases, the relative pupil size increases. Relative pupil size shows the same trend as the relative change in illuminance at the eyes and the discomfort glare perception.

Energy-Saving Performance Studies of Road Tunnel Luminaries

2013 ◽  
Vol 291-294 ◽  
pp. 654-660
Author(s):  
Chao Yang ◽  
Shi Juan Fan
Keyword(s):  
Energy Saving ◽  
Light Emitting Diode ◽  
Road Surface ◽  
Light Sources ◽  
Road Tunnel ◽  
Lighting Condition ◽  
Average Luminance ◽  
Tunnel Model ◽  
Lighting Simulation ◽  
Reasonable Choice

Reasonable choice of light sources was the key to achieve energy-saving of tunnel lighting. Performance comparisons of light sources were completed, tunnel model was designed with lighting software-DIAlux based on characteristics and design demands of tunnel lighting. Simulation experiments for HPS (high pressure sodium) and LED (light-emitting diode) were made in the tunnel model, lighting effects of HPS and LED in each zone of the tunnel were analyzed, the results show that LED has higher lighting efficiency and can save more 40% power energy than HPS under the same lighting condition and the same road surface average-luminance, and LED has better road surface lighting effects and better color rendering than HPS.

scholarly journals Measuring the Lighting Quality in Academic Institutions: The UPM Faculty of Aerospace Engineering (Spain)

2020 ◽  
Vol 10 (23) ◽  
pp. 8345
Author(s):  
María Zamarreño-Suárez ◽  
Daniel Alcala-Gonzalez ◽  
Daniel Alfonso-Corcuera ◽  
Santiago Pindado
Keyword(s):  
Measured Data ◽  
Simulation Software ◽  
Aerospace Engineering ◽  
Fine Tuning ◽  
Current Status ◽  
Test Results ◽  
Wear And Tear ◽  
Lighting Simulation ◽  
Low Levels ◽  
Lighting Systems

This article analyzes the current status of the lighting quality at the Escuela Técnica Superior de Ingeniería Aeronáutica y del Espacio (ETSIAE), the aerospace engineering faculty at the Universidad Politécnica de Madrid (UPM), and evaluates possible improvement actions based on the use of DIALux® lighting simulation software together with measured data. The results show rather low levels of measured illuminance on classroom desks and blackboards in one of the buildings comprising the faculty. The improvements proposed (a new coat of paint on the walls and replacement of luminaires) were simulated in four individual classrooms representing all rooms in two of the ETSIAE buildings (where the lower illuminance levels were measured). In order to study these improvements, the current situation of the four selected classrooms was simulated using DIALux® and fine-tuning attenuation of the luminaires to take into account their wear and tear. The correlation between the DIALux® simulation and the test results was analyzed with quite good results. The results clearly reveal a need to fully replace the classroom lighting systems in ETSIAE building A (the oldest building, dating back to 1955). According to the results from the selected classrooms, the average lighting over the desks can be greatly improved by using LED technology in order to meet UNE 12464-1 standard (that is, 500 lx, from an initial situation with much lower illuminance values: 129 lx to 295 lx). This article represents an innovative way to perform lighting improvement projects as real measured lighting data is used as initial input for the lighting simulations.

scholarly journals Bright Light Sources

Nature ◽  
1945 ◽  
Vol 155 (3931) ◽  
pp. 265-265
Keyword(s):  
Bright Light ◽  
Light Sources

scholarly journals The Effect Of Display Brightness On Visual Function For Young And Old Drivers

2021 ◽  
Vol 1202 (1) ◽  
pp. 012036
Author(s):  
Gatis Ikaunieks ◽  
Gunta Krumina ◽  
Liva Volberga ◽  
Lauris Naumovs
Keyword(s):  
Visual Function ◽  
Age Groups ◽  
Luminance Level ◽  
Outdoor Advertising ◽  
Lighting Conditions ◽  
Discomfort Glare ◽  
Disability Glare ◽  
Older Subjects ◽  
Young Subjects ◽  
Method Of Adjustment

Abstract Nowadays outdoor advertising displays have become popular. Bright displays near the roads could cause drivers to experience disability or discomfort glare, especially at night. Disability glare increases with age, but discomfort glare thresholds are independent of age. The aim of the study was to assess a luminance level of displays, which causes glare for younger and older subjects. 24 young subjects age of 20 to 24 years and 13 older subjects age of 55 to 69 years participated in the study. The task was by using the method of adjustment to find out the acceptable level of display brightness when the recognition of high (>90%) contrast objects was comfortable. Measurements were done in a photopic and mesopic lighting conditions. Results showed that discomfort glare were larger in mesopic than in photopic lighting conditions (p < 0.001) for both age groups. Preferred display brightness in both lighting conditions did not significantly differ between age groups (p > 0.05). We can conclude that discomfort glare thresholds for displays with textual elements are independent of age.

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