Leukos最新文献

{"title":"Association between Perceived Daylit Area and Self-reported Frequency of Electric Lighting Use in Multi-dwelling Buildings","authors":"I. Bournas","doi":"10.1080/15502724.2020.1851606","DOIUrl":"https://doi.org/10.1080/15502724.2020.1851606","url":null,"abstract":"ABSTRACT This paper examines the association between daytime electric lighting use and perceived indoor daylight availability in residential spaces. In addition, occupant preferences were evaluated, in particular which rooms are prioritized in terms of daylight availability. The study deployed a questionnaire survey that was carried out in typical multi-dwelling apartment blocks in Malmö, Sweden (Latitude: 55.6 °N). Occupants were asked to report how often they use electric lighting during daylight hours (EL) in their kitchen, living room and main bedroom, and how much of the floor area they perceive as adequately daylit (DA) throughout the year. Responses EL and DA were measured in seven-point semantic differential scales, and were correlated (Spearman) to evaluate their association for different room groups. Groups were based on age, room function, façade orientation, balcony obstruction and fenestration geometry. In addition, occupants were asked which room they would choose if there had to be one underlit room. Results indicate that EL is strongly associated with DA in the overall room sample (rS = −0.588, p < .01, n = 225). The association is persistent across room groups of different characteristics, with the Spearman rank correlation coefficient ranging between −0.4 and −0.8, and not differing significantly between groups. In terms of preferences, a significantly high proportion of participants would choose the bedroom if there had to be one underlit room (62%, p < .05), while the kitchen was selected by only 5 out of 108 respondents.","PeriodicalId":49911,"journal":{"name":"Leukos","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2021-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79496818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of Color-Matching Primaries on Observer Matching: Part I – Accuracy","authors":"Jiaye Li, P. Hanselaer, Kevin A. G. Smet","doi":"10.1080/15502724.2020.1864395","DOIUrl":"https://doi.org/10.1080/15502724.2020.1864395","url":null,"abstract":"ABSTRACT A good color description starts with the availability of accurate color-matching functions (CMFs) or cone fundamentals (CF). Recent work indicates a discrepancy between visual metamers and those calculated using the standard CIE CMFs or other CMF sets, especially for narrowband sources. In the current study, 54 observers (varying in age, gender, ethnicity, and eye color) performed a series of achromatic color-matching experiments with a 10° stimulus using eight different narrowband primaries under an immersive, perceptually neutral (4673 K) viewing conditions. The reference stimulus was provided by a 70 cd/m2 gray (4613 K) card illuminated by a spectrally broadband light source. The results confirm that substantial and significant differences between experimental and calculated metamers exist, particularly when a short wavelength primary (404 nm) is included and especially for the CIE 1931 2° CMFs. It is found that the primary set characterized by the peak wavelengths 636 nm, 521 nm, and 447 nm, which are close to those of typical RGB primaries widely used in industry, results in the most stable matching performance across all CMF sets. Finally, in addition to the impact of primary wavelength and CMF set, the potential effect of age, gender, ethnicity, and eye color has also been investigated. The effect of age on the color matches is found to be significant and is due to differences in spectral sensitivity of young and old observers with respect to the blue primary; the impact of observer gender, ethnicity, and eye color, on color-matching accuracy is not significant.","PeriodicalId":49911,"journal":{"name":"Leukos","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2021-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86285234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Window Views: Difference of Perception during the COVID-19 Lockdown","authors":"A. Batool, P. Rutherford, P. McGraw, T. Ledgeway, S. Altomonte","doi":"10.1080/15502724.2020.1854780","DOIUrl":"https://doi.org/10.1080/15502724.2020.1854780","url":null,"abstract":"ABSTRACT The provision of daylight, fresh air, and of a view outdoors are among the known characteristics of windows. But how does the perception of a window differ when it becomes the primary way of connecting to the physical world outside? In the first half of 2020, many countries resorted to strict lockdown measures to control the spread of the SARS-CoV-2 virus. The impact of such confinement, and the restriction to movement and social contact between people, is currently undergoing intense research. As such, this study reports the findings of a global online survey, administered before and after the COVID-19 outbreak, aimed at identifying whether any significant difference related to the lockdown could be observed in the perception of windows. The results confirm a practically relevant increase in the importance given to windows as a way to provide an external view and a visual and social connection with other people. Conversely, the role of the window as a conveyor of information on weather and time of the day was less prevalent. This is one of the first studies evaluating the difference in the perception of windows within a period of enforced lockdown. The findings can help capture the psychological impacts of confinement on people and may be relevant when transferred to other domains where building occupants could strongly benefit from the restorative effects of window views.","PeriodicalId":49911,"journal":{"name":"Leukos","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2021-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85979121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Different Spectral Power Distributions on Mesopic Visual Performance with Blue Light-filtering Intraocular Lens","authors":"E. Vicente, I. Arranz, D. Galarreta, P. Barrionuevo, M. Rodríguez-Rosa, S. Mar, JA Aparicio, B. Matesanz","doi":"10.1080/15502724.2020.1757461","DOIUrl":"https://doi.org/10.1080/15502724.2020.1757461","url":null,"abstract":"ABSTRACT The purpose of this work is to analyze the interaction between the spectral transmittance of old-aged subjects, before and after cataract surgery and blue light-filtering intraocular lens implantation, and the spectral power distribution of common street lamps, under conditions typical of nighttime driving. We analyzed contrast threshold and visual reaction time in off-axis vision at different mesopic illumination conditions provided by high-pressure sodium and metal halide lamps. Three groups of subjects with different spectral transmittances participated: young subjects as control group, old-aged subjects with senile cataracts and the same subjects after cataract surgery and blue light-filtering IOL implantation. A clear interaction appears between the spectral power distribution and the spectral transmittance, depending on the visual task. Transparent ocular media allow benefiting from the greater short-wavelength content of the halide lamp. However, cataracts increase contrast threshold and visual reaction time values and also affects how the spectral power distribution influences these visual tasks. After surgery and intraocular lens implantation, visual performance improves for both lamps and the blue light-filter seems to influence spectral transmittance, which affects visual performance under light provided by greater short-wavelength content lamps. Cataract surgery is responsible for an improvement in contrast threshold and visual reaction time tasks, though blue light-filtering of the intraocular lens seems to prevent the visual system from benefiting from lamps with greater emission at short wavelengths.","PeriodicalId":49911,"journal":{"name":"Leukos","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82965444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimates, Precision, Accuracy, and Adaptation in Applied Lighting","authors":"K. Houser","doi":"10.1080/15502724.2020.1834283","DOIUrl":"https://doi.org/10.1080/15502724.2020.1834283","url":null,"abstract":"Estimates, precision, and accuracy all involve the concept of error, but in different ways. An estimate is an approximate prediction of the amount of something. Precision refers to the reproducibil...","PeriodicalId":49911,"journal":{"name":"Leukos","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90294242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization of luminaire layout to achieve a visually comfortable and energy efficient indoor general lighting scheme by Particle Swarm Optimization","authors":"Purnima Mandal, D. Dey, B. Roy","doi":"10.1080/15502724.2018.1533853","DOIUrl":"https://doi.org/10.1080/15502724.2018.1533853","url":null,"abstract":"ABSTRACT The design of an indoor lighting system for a sustainable building should comply with the recommended maximum limit of lighting power density. The occupants’ visual comfort and visual performance are to be ensured by complying with some mutually conflicting lighting design parameters, such as maintained average illuminance, overall uniformity, and maximum unified glare rating, to the recommended limits. Judicious balance among these multiple conflicting design parameters is a practical design problem. This article aims to address these aspects of indoor lighting design by applying a particle swarm optimization (PSO) algorithm in a developed lighting computation program. The objective function is formulated with maximum or minimum limits for the design parameters recommended by international standards. The effectiveness of the developed program is evaluated by designing an indoor lighting system with commercially available luminaires for an office space that ensures optimized visual comfort, energy efficiency, and initial cost. Optimized results are validated by DiaLux simulation and a maximum deviation of 2.27% is found. Thus, the results show good agreement with DiaLux simulation and significant improvement in the uniformity of illuminance (0.90) compared to the recommended minimum value (0.70) and in discomfort glare (16) compared to the recommended allowable maximum value (19). The developed program establishes the usefulness of the PSO algorithm to optimize the luminaire layout for an indoor general lighting scheme.","PeriodicalId":49911,"journal":{"name":"Leukos","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/15502724.2018.1533853","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72421769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preferred luminance distributions in open-plan offices in relation to time-of-day and subjective alertness","authors":"Christel de Bakker, M. Aarts, H. Kort, E. van Loenen, A. Rosemann","doi":"10.1080/15502724.2019.1587619","DOIUrl":"https://doi.org/10.1080/15502724.2019.1587619","url":null,"abstract":"ABSTRACT Dynamic lighting is one of the new trends in lighting research; providing the right lighting level at the right time could possibly increase the alertness and performance of office workers. However, they might have preferences that deviate from this “healthy” lighting. Simultaneously, the building environment becomes increasingly automated, with occupancy-based control as one of the most well-known examples to reduce offices’ lighting energy consumption. Nevertheless, preferences for lighting levels in the unoccupied area of the multi-occupant office space have not been addressed yet. Therefore, we studied luminance distribution preferences in relation to time of day and subjective alertness (SA) in a single occupancy scenario. Participants (N = 30) set the surrounding and background lighting six times a day as we first probed for SA. Our results clearly showed that a subset preferred varying luminance distributions; participants had fluctuating feelings of alertness, too. Preferences deviated sometimes from the typical dynamic lighting scenarios, suggesting that they do not always prefer healthy lighting. Moreover, we identified an effect of SA on the preferences, both with and without controlling for time of day. Hence, this study showed that we need to address these two factors when we want to provide satisfactory lighting conditions in case the office is not fully occupied. These are likely to affect other lighting preferences and therefore deserve more attention from research. Because we identified large individual differences, we suggest personalizing dynamic scenarios as the focus of future research.","PeriodicalId":49911,"journal":{"name":"Leukos","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83627466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Calibration and Validation of Climate-Based Daylighting Models Based on One-Time Field Measurements: Office Buildings in the Tropics","authors":"G. Quek, J. Jakubiec","doi":"10.1080/15502724.2019.1570852","DOIUrl":"https://doi.org/10.1080/15502724.2019.1570852","url":null,"abstract":"ABSTRACT Calibrated climate-based lighting simulation models of buildings have the capacity to perform an essential role in postoccupancy evaluations, such as annual frequency assessments of daylighting quality and visual discomfort. However, in most postoccupancy case studies the role of lighting analysis is temporally limited by instantaneous measurements or limited in scale by requiring constant monitoring with expensive sensors. It is challenging to build calibrated models based on point-in-time measurements due to the presence of electric lighting, transient use of dynamic shades, limited information on the material specifications, and short durations of accessibility to the spaces being studied. The authors propose and present a calibration process for annual daylighting and electric lighting simulation models based on one-time field measurements of large daylit and electrically lit spaces exemplified through a data set of 540 individual office desks across 10 office spaces. The calibration process includes measuring lighting, physical, and material data during a one-time visit that are used to calibrate high dynamic range images and lighting simulation models using actual weather data. The calibration accuracy is validated based on measured and simulated luminance and illuminance data. Comparing measured and simulated illuminance, relative root mean squared error (RMSE) values were 25.8% and 45.5% for horizontal and vertical measurements, respectively. When tracking errors using log10(illuminance), approximating human perceptual differences, errors of 4.3% and 6.8% were achieved. Vertical illuminance was found to vary more with measured data due to the uncertainty of monitor screen luminances. The authors aim to achieve calibrated lighting models that are reliable enough to be used in assessing the relationship of annualized lighting metrics to participants’ long-term perceptions of lighting quality, thereby enabling simulation models to be used in the postoccupancy evaluation process of building lighting. This article demonstrates that measured data through one-time visits can be utilized to build reliable calibrated lighting simulation models to integrate long-term annual lighting results in postoccupancy evaluations.","PeriodicalId":49911,"journal":{"name":"Leukos","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91125700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Change of Gamut Size for Producing Preferred Color Appearance from 20 to 15000 lux","authors":"Wenyu Bao, M. Wei","doi":"10.1080/15502724.2019.1587621","DOIUrl":"https://doi.org/10.1080/15502724.2019.1587621","url":null,"abstract":"ABSTRACT Numerous efforts have been made to investigate how light source color rendition affects color preference. Though the effect of light level on color appearance (known as the Hunt effect) was found in 1952, most studies investigating color preference under light sources only employed a single illuminance level and the illuminance levels were typically between 200 and 1000 lux. This article reports two psychophysical experiments that were designed to investigate how light source color rendition affected color preference across a wide range of illuminance levels, from 20 to 15,000 lux. The observers compared the color appearance of an artwork under nine nearly metameric light stimuli with a correlated color temperature (CCT) of 3000 K at different illuminance levels. These light stimuli were carefully designed to have different abilities to enhance the chroma of red and green colors, so that they had different gamut areas R g (between 100 and 124 in Experiment 1 and between 99 and 117 in Experiment 2). It was found that the illuminance level significantly affected the observers’ judgments, with a light stimulus with a greater R g being preferred at a lower light level. The light stimuli with an R g beyond 100 were preferred at the light levels from 20 to 5000 lux, whereas those with an R g around 100 were preferred at very high light levels (i.e., 10,000 and 15,000 lux). This suggested that the preference to the stimuli with an R g beyond 100, as found in many past studies, was likely due to the relatively lower illuminance levels in comparison to the daylight illuminance levels. In addition, the calculations of the color attributes of the artwork under the preferred stimuli suggested that CIECAM02 may overestimate the effect of light level on color appearance, especially when the light level was very high, which merits further investigations.","PeriodicalId":49911,"journal":{"name":"Leukos","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75924140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sensory Evaluation of Lighting: A Methodological Pilot","authors":"Magdalena Boork, J. Nordén, M. Nilsson Tengelin, K. Wendin","doi":"10.1080/15502724.2020.1813037","DOIUrl":"https://doi.org/10.1080/15502724.2020.1813037","url":null,"abstract":"ABSTRACT Current standards for light environments are based on technical requirements, e.g. luminance, uniformity, and illuminance, and do not necessarily describe all parts of the light experience to ensure visual comfort from a user perspective. Including experience-related requirements would most likely yield better lighting comfort. To do that, new methods for specifying and measuring the user experience are needed. This paper describes a pilot study exploring a new method to analytically assess perceived lighting properties by using a trained human panel and thus make human assessments more objective. The methodology is built on established sensory methods, where the human senses are used in product assessments, traditionally applied within e.g. the food, packaging, and car industries. An analytical panel comprising eight persons fulfilling specific selection criteria were recruited and trained to assess lighting products in a multi-sensory laboratory. The results show that the panelists were able to assess lighting by distinguishing between attributes and products. Significant differences were identified between the different luminaires, both in terms of sensory and physical properties, e.g. readability and glare. Conclusively, analytical sensory methods can be applied to lighting to assess luminaires in a non-subjective way. Physical and sensory attributes do not, however, always co-vary, which shows that data from physical and sensory measuring methods provide complementary information about light quality. This knowledge may in turn be applied in tools supporting the communication between different professions in lighting design and procurement to promote light environments that are both energy efficient and desirable from an end-user perspective.","PeriodicalId":49911,"journal":{"name":"Leukos","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2020-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76340460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}