Interior Illumination Research Articles

Solar-optical and thermal behavior of photochromic glazing: Small-scale testing under real sky conditions

The poor performance of conventional building glazing, which is usually responsible for large climatization needs and glare problems, has been promoting the development of innovative smart glazing technologies with an improved performance. Photochromic glazing, a type of smart glazing, exhibits a dynamic behavior by darkening/bleaching in reaction to the presence/absence of solar radiation. The aim of this study is to evaluate the thermal and solar-optical behavior of a photochromic filmed clear glazing, against the same glazing without film, through experimental tests. The transmittance and reflectance spectra of the glazing solutions were initially measured with a spectrophotometer. Then two small-scale models were used to assess the behavior of the glazing solutions under real sky conditions (clear and overcast). The thermal behavior was assessed through air and surface temperature measurements. The solar-optical behavior was investigated through solar radiation and illuminance measurements, which were also used to compute the solar and visible transmittance of the glazing systems, respectively. The dynamic behavior of the photochromic film resulted on a reduction of 14 % of the interior temperature. Interior illuminance and irradiance levels were significantly reduced with the film, corresponding to 10–50 % and 15–35 % visible and solar transmittance values of the photochromic glazing, respectively.

Daylighting and energy performance optimization of anidolic ceiling systems for tropical office buildings

A simple window is often unable to ensure standard illumination to the deep parts of large office spaces, and advanced daylighting systems are necessary to ensure the level of interior illuminance. Anidolic ceiling systems are one of the less popular daylighting strategies designed to redirect and redistribute daylight deeper, which can reduce the demand for artificial lighting and energy use for lighting purposes. This study shows how a parametric approach can be applied to optimize the daylighting and energy performance of an anidolic ceiling system in a tropical climate. Multi-objective optimization (MOO) techniques were applied to combine different design variables to establish multiple design alternatives and find the optimal design by comparing their performances. A simulation study of an anidolic ceiling system was conducted with test models primarily developed by Rhinoceros and ClimateStudio, and optimization of performance metrics was conducted using Grasshopper and Octopus. Data exportation was done using the TT toolbox, while data analysis was done through mathematical and statistical analyses and cross-checked by Design Explorer. By incorporating an optimum anidolic ceiling system into the case office space, spatial daylight autonomy (sDA) increased 20.51 %∼68.18 %, annual sunlight exposure (ASE) decreased 15.83 %∼8.52 %, mean illuminance increased 221 lux–3027 lux and energy use intensity (EUI) reduced 189.3 kWh/(m2y)∼174 kWh/(m2y) for different configurations of test models. The results demonstrated a MOO methodology that successfully finds the optimum solutions for the anidolic ceiling systems in a deep plan office space to enhance daylighting and energy performance.

Interior Illumination Impact on Night Driving in a Driving Simulator

Automakers are beginning to include larger and brighter tablet-style interfaces in their vehicles. The amount of light emitted from these large interfaces could cause issues with driver distraction and might degrade performance. In the following study, the impact of bright lights from the interface on driver performance and object detection was studied.

Simulation-based analysis of window paper effects on daylighting of traditional Beijing siheyuan

Paper is a widely used light-transmissive material in Chinese traditional buildings. To establish and simulation methods for window paper and study the temporal and spatial features of daylighting in Beijing siheyuan, we conducted model measurements and simulations based on dynamic meteorological parameters in the main and side houses. It has been found that in comparison with glass, window paper has following features in terms of daylighting: (1) It improves the uniformity of illuminance in a room and reduces seasonal differences in illuminance; (2) It can improve ground illuminance and the illuminance at the rear wall, and reduce work plane illuminance near the window; (3) It reduces interior illuminance in general and increases the chance of glare in the main house at noon in winter. This study clarified the lighting significance of window paper and provided a reference for the application of diffuse transmissive materials with window paper-like effects.

The Influence of Photovoltaic Light and Heat Environment of Ceramic Studio on Making Technology and Human Health

To study the influence of the Photovoltaic light and heat environment of the ceramic studio on human health and ceramic production technology, we take the ceramic studio of a university in Wuhan as the research object. And we use data processing and fitting algorithm to build the model. This paper provides a basis for improving the photothermal environment of ceramic studios in Wuhan. The results show that the indoor illumination of a one-sided window studio in the daytime is significantly lower than that of a two-sided window studio. The studio with one side window had about 80 Lx (unit of illuminance) less daytime interior illumination than the studio with two sides. In terms of illumination, the illumination of the studio with single-side Windows is about 100 Lx in the daytime, and that of the studio with double-side Windows is about 180 Lx.

Synthesis of an efficient Mn4+-doped fluoride red phosphor with excellent fluorescence stability by green synthesis method for warm WLED

Currently, Mn4+-doped fluoride phosphors have become a research hotspot, which can help compensate for the missing red component in cold white light-emitting diodes (WLEDs). However, significant synthesis defects limit the development of such fluorescent powders due to the use of highly toxic solvent HF. To improve this situation, a simple green synthesis method should be explored to synthesize Mn4+-activated fluoride phosphor. In this study, a series of red-emitting Mn4+-activated BaTiF6 phosphors are successfully synthesized via the non-toxic reaction system (HNO3/HCl + NH4F). Its crystal structure, morphology, optical characteristics and thermal stability are systematically evaluated. Under blue light excitation, BaTiF6:Mn4+ exhibits a bright narrow-band red emission with exceptional correlated color temperature (3909 K) and color purity (90%). Additionally, the critical concentration of Mn4+ is determined to be 0.03 and the concentration quenching mechanism is also systematically discussed. By calculating the crystal field strength (Dq), Racah parameters (B and C) and nephelauxetic effect ratio parameter β1, it is confirmed that BaTiF6 host can provide a strong crystal field environment for Mn4+. Moreover, these results are compared with other matrix materials. Intriguingly, the optimal sample exists satisfactory thermal stability, whose fluorescence intensity at 423 K retains 49% of that at 298 K and the activation energy reaches up to 0.925 eV. In addition, the chromaticity shift and chromaticity coordinate variation are calculated as 17 × 10−3 and (−0.0063, 0.0063), respectively. Meanwhile, the feasibility of the as-fabricated WLEDs for interior illumination is examined. A high-performance warm WLED with low correlated color temperature (CCT = 4470 K) and high color rendering index (Ra = 88.3) is achieved by using BaTiF6:Mn4+ as a red-emitting material, moreover, WLED exhibits strong output stability under high driving current. The findings of this work provide a comprehensive understanding for rational design of high-performance Mn4+-activated fluoride red phosphors through a simple green synthesis method.

Hybrid solar lightning system for home lightning

The use of renewable energy is becoming more prevalent in today’s world. The study investigates a hybrid system for interior illumination at a workplace that blends natural light (daylight) with artificial light sources (a conventional system). A sun-tracking Parabolic Concentrator and Fiber Optic Cables device collects Solar Irradiance in the form of light. This technique is beneficial in terms of energy savings, economic efficiency, human health, and reduces environmental emissions. The solar hybrid day lighting using fiber optics can meet the required load demand in a cost-effective way, potentially lowering traditional energy costs for electricity. Thus, the fiber optic cable is the best for the transmission of natural light.

Post Occupancy Evaluation of the Luminous Environment in Algerian University Classrooms

The luminous environment is one of the most important physical parameters in a teaching space (classroom) due to its impact on the intellectual performance of students, their health and their behavior. The aim of this study is to evaluate the luminous environment in university classrooms located in Constantine, the main university hub of the East of Algeria. A Post Occupancy Evaluation (POE) based on the objective and subjective assessment was carried out at the Department of Psychology of Constantine 2 University in North and West facing classrooms. This study was conducted during the three periods: winter, spring and summer, under clear sky and overcast sky conditions. The objective variables measured by a luxmeter during each course session are: indoor illuminance levels (Ei) on work plan, vertical illuminance levels on boards (Ev), uniformity index (Uo) and outdoor illuminance levels (Ex). At the same time, students perception and satisfaction were reported by a longitudinal questionnaire (N=1221) using subjective scales. The objective assessment shows that the mean interior illuminance is dependent of the sky-type, and it varies with outdoor illuminance. We notice that illuminance levels in north classroom are below the recommended value especially under overcast sky. The illuminance levels in west facing classroom are excessive during the afternoon under clear sunny sky. However, students show a remarkable degree of adaptation to different light levels. They use controls to modify the light level at their work plans.

Review: How Sherlock Pulled the Trick: Spiritualism and the Pseudoscientific Method, by Brian McCuskey

Review: <i>How Sherlock Pulled the Trick: Spiritualism and the Pseudoscientific Method</i>, by Brian McCuskey

Domain Adaptation in Automatic Picking of Phase Velocity Dispersions Based on Deep Learning

AbstractAmbient seismic noise tomography has been applied to probe the Earth's structure. To accurately map geological structures, a considerable amount of time is required to pick fundamental and higher modes of dispersion curves. We used frequency‐Bessel (F‐J) transform to calculate phase velocity‐frequency diagrams to obtain more higher modes of dispersion curves from the cross‐correlation function. Several studies have recently focused on picking dispersions automatically using deep learning to reduce time consumption. However, the generalization of neural networks has a degradation for untrained diagrams to some degree. Here, based on domain adaptation in computer vision, we used gamma transform to change the image contrast of the phase velocity‐frequency diagrams, rendering the test data closer to the training data. Introducing domain adaptation into the dispersion region extraction effectively improves the generalization of the neural network. Here, the dispersion regions are the regions in the phase velocity‐frequency diagram located around the dispersion curves where the energy is above a given threshold. We validated our method by using phase velocity‐frequency diagrams from different areas. We used one synthetic phase velocity‐frequency diagram and three phase velocity‐frequency diagrams of different areas to test domain adaptation. In particular, we tested one phase velocity‐frequency diagram that belongs to the same area for the training diagram, except for the processing steps. The results showed that our domain adaptation method successfully enhanced the generalization of the neural network. After domain adaptation, our trained network could effectively extract more higher modes of dispersion regions than before. Our dispersion curves picking method combined with domain adaptation can pick sufficient dispersion information for numerous phase velocity‐frequency diagrams. Furthermore, our method can facilitate the study of ambient noise tomography and illumination of the Earth's interiors. Our research provides a strategy for enhancing the generalization of neural networks for other deep learning‐based geophysical image segmentation tasks.

Future Manifestation of Lighting in Sacred Landscapes Through Analyzing the Existing Sacred Structures

Lighting in sacred structures is an important part of architecture as it has physical and psychological impact on visitors and also influences how well a space is perceived. This research study intends to demonstrate that how expressions of light and daylight factor have a significant impact in the structure's design. The study utilizes a mixed method approach, with qualitative and quantitative analysis of lighting levels and visual integration of numerous sacred spaces, studied and compared through case studies. The findings aided in the development of guidelines for individual, collective and sacred lighting of landscapes in order to heighten the sense of sanctity inside the area. Since this study mainly focuses on natural illumination in the horizontal plane, more research can be conducted focused on the use of artificial lighting levels. The vertical plane, which incorporates walls and openings, can also be considered to see how it alters interior illumination.

Localization using interior illumination reflected on cornea and inertial measurement unit

Localization using interior illumination reflected on cornea and inertial measurement unit

Influence of scale on the daylighting system evaluation in physical models: Experimental method based on objective and subjective measurements

The daylight evaluation in architectural spaces can be carried out using several tools and methods of investigation and analysis. However, many types of research have proven the usefulness of the scale models to evaluate daylighting system performances in buildings. Several scales of a physical model have been used varying between (1:50) and real scale (1:1), and no comparative study has been done to evaluate the effect of the model size in daylighting assessment. The objective of this investigation is to make a comparison between two different scales of a physical model: the first one is a model with a scale of (1:12) while the second is with the scale of (1: 4), aiming to study the scale effects on daylight perception with models equipped with a daylighting system under very high exterior illuminance levels. The methodology of this study consists in collecting simultaneously the measurement of the exterior and interior illuminance level (lux) and subjective evaluations from a questionnaire survey with the two scale models (1:4 and 1:12) under real sky conditions. A correlation between collected data has been explored. Comparing the measurement results, it is obvious that the quantity of light that penetrates the test models (1:4 and 1:12) was the same. The results are with a range of ±1.6%. Moreover, survey results show that the participants’ perceptions regarding satisfaction, light distribution and glare questions differ with the scale of the physical 3D model. The subjects felt more satisfied with the luminous atmosphere with the physical model of (1:4) compared with the model of (1:12).

Estimating Global Solar Radiation from Empirical Models: An Application

Solar radiation data are required for many applications and many areas of research. In order to achieve this, several empirical models have been suggested to predict the global solar radiation in Turkey and other countries. The different meteorological data as the global solar radiation, the sunshine duration, the temperature, the atmospheric pressure, the wind speed and the relative humidity were measured by Eskisehir Osmangazi University during the period between 01 January 2011 and 31 December 2014. These data were used to develop the empirical models in order to estimate the monthly average daily global solar radiation on the horizontal surface over Eskisehir City of Turkey. The developed empirical models were analyzed with the widely used nine statistical methods, namely; the relative percentage error (E), the mean percentage error (MPE), the mean absolute percentage error (MAPE), the sum of squares of relative errors (SSRE), the relative standard error (RSE), the mean bias error (MBE), the root mean square error (RMSE), the t-statistic method (t-stat) and coefficient of determination (R2). It is expected that the new model will be beneficial to everyone who is the solar engineers, architects, agriculturists, and hydrologists involved or interested in the design and study of solar energy applications such as solar furnaces, wood drying, stoves, concentrating collectors, interior illumination and thermal load analyzing of buildings, and photovoltaics, agricultural and meteorological forecasting.

Simulation study for a switchable adaptive polymer dispersed liquid crystal smart window for two climate zones (Riyadh and London)

Polymer dispersed liquid crystal (PDLC) is an electrically switchable smart window, that can provide privacy and control solar radiation, resulting in a potential energy saving. The optical properties of the PDLC window can be altered from translucent to transparent when an alternating current power supply is applied. However, little attention has been paid to the PDLC smart window in terms of overall building energy performance. Therefore, this study aims to investigate the impact of the PDLC window on heating, cooling, and lighting loads and daylight performance, for an office building utilising energy building modelling and daylight analysis tool. The study is limited to two contrasting climate zones; an arid climate (Riyadh, Saudi Arabia) and a temperate climate (London, United Kingdom). The results showed that the PDLC window was more effective in Riyadh (arid climate) with a cooling reduction of 12.8% than London (temperate climate) with a heating reduction of 4.9%. PDLC provided excellent interior illuminance in both cities.

Egg covering in cavity nesting birds may prevent nest usurpation by other species

Some birds cover their eggs with nest material when they leave to forage. It has been suggested that such egg-covering aids thermoregulation or prevents predation but here we present a new hypothesis, that secondary cavity-nesting species cover their eggs to prevent nest usurpation by other birds. When the bottom of the cavity is dark, as when eggs are covered by nest material, it may be difficult for a prospecting competitor to see whether a defending nest owner or a predator is hiding inside the cavity. Competitors may therefore hesitate to enter dark cavities. We filmed 21 great tit (Parus major) nests during the egg-laying period and found that the female spent bouts of highly variable length outside the nest box (range 0.3–250 min, n = 51), so prospecting small passerines would have difficulty predicting whether an aggressive tit owner was in the box or would soon return. We presented prospecting male pied flycatchers (Ficedula hypoleuca) with a dyad of boxes (n = 93), each containing a great tit nest but only one with visible eggs. Flycatchers hesitated more to enter a nest box with no visible tit eggs than a box with exposed eggs. This was most evident for nest boxes with dark versus light interior paint, supporting the idea that better interior illumination makes prospecting birds more confident about entering an unfamiliar cavity. The usurpation and predation hypotheses are not mutually exclusive because both competitors and small predators may hesitate to enter dark, enclosed spaces if visibility is low.Significance statementSome birds deposit a layer of material on top of the eggs when they leave the nest. Several hypotheses have been proposed for such egg covering, for example that it may insulate the eggs and reduce the risk of nest predation. We propose a new hypothesis, namely that secondary hole-nesting birds cover their eggs when they leave the nest to prevent usurpation of the cavity by other birds. Great tits that we filmed at the nest during the egg-laying period could be absent for long periods. To test the hypothesis, we presented male pied flycatchers, potential nest competitors, with a dyad of nest boxes, each containing a great tit nest but only one with visible tit eggs. In support of the prediction, prospecting flycatchers hesitated to enter dark cavities with dark floors relative to boxes with exposed, reflective eggs.

“Home Is The Theater Of Life”: Scenographic Poetics And American Living Room Ambience, 1900–1925

Proceeding from the notion of scenography as atmosphere or ambience, this article explores scenographic design elements aimed at a range of American middle-class living rooms during the early-twentieth century when these newly configured domestic interior spaces replaced Victorian parlors, libraries, and drawing rooms as gathering places for both private family activities and those social occasions when friends and guests were invited into the home. Looking to the period’s theatre with its realistic, natural portrayal of family life as unfolding in the living room, spokespersons for the emerging professions of interior design and illumination engineering spearheaded a call for replicating the aesthetics of theatre atmosphere in living rooms through the manipulation of artificial light at a time when rapid innovations in electric lighting were beginning to transform public and private spaces. Through the utilization of the new “color science” housewives could create the proper atmosphere for any occasion through an inviting scenographics of illuminated fixtures, decorative furnishings, and wall treatments that radiated a pleasing harmony of refinement and relaxation.

Redistributions of luminance patterns on standard sky types

There is insufficient current knowledge on the sky luminance patterns under ISO/CIE standard sky types in absolute luminance physical units in cd.m−2 and the resulting horizontal skylight illuminance in lux at the ground level. This paper explains research results and formulae to enable determination of computer applications which help in any location and time to calculate the distribution of luminance in any sky element on outdoor surfaces or within window solid angles that cause interior illuminance perception problems and, or discomfort glare.

A Comparative Study of Artificial Intelligence Models for Predicting Interior Illuminance

ABSTRACT Thanks to the recent advances in computer technology, many building energy performance simulation tools have been developed in the current market. Designers and architects are interested in working on this topic in the early phases of the project. However, effective energy solutions are computationally expensive. As a result, having a comprehensive insight into the project conditions in the early phases of the work is a vital issue. The present study aimed to propose an artificial intelligence (Al) model to generate a reasonably accurate estimate in a short time. To this end, four machine learning models and one artificial neural network (ANN) are selected and their results are compared to assess their capabilities in energy performance estimation. This study investigates the influence of the exterior louver design on the interior energy performance of a structure. A specific dataset is generated and tested on four powerful regression models (i.e., polynomial Linear Regression, Random Forests (RF), Decision Tree (DT), and Support Vector Regression (SVR)) and one Artificial Neural Network (ANN). Finally, a comparative analysis is presented. The findings of this research support the use of machine learning tools and ANNs as a convenient and accurate strategy for predicting building parameters.

Selection of the control alternative with the minimum energy consumption for the hybrid illumination system of inner spaces

The use of daylighting reduces energy consumption in buildings, which can be achieved by the implementation of the hybrid illumination systems (HIS). In general, the solutions of HIS exercise high controllability on every luminary for minimizing the energy consumption while maintaining the desired illuminance level by users. Nevertheless, it is only considered the demanded power by luminaries despite to auxiliary components (e.g. sensors, power-packs, and controllers) operate full time and their energy consumption may be representative. Therefore, this study proposes a procedure for sizing HIS for inner spaces with the lowest annual energy consumption (AECHIS) based on an exhaustive search. All of the possible control alternatives are determined by a combinatory process considering calculation using Stirling number of the second kind, the number of control groups, and the number of available control strategies. The modelling of interior illuminance is based on the daylight factor matrices, the incident solar irradiation on each opening, the illuminance contribution by luminaries, and the operation conditions of control alternative. AECHIS is defined as a function of number and power consumed by luminaries (Plum) and auxiliary components (Paux) considering operating conditions of HIS for every time-interval. Plum is defined as an MINLP problem that depends on the state (On or Off) and luminous flow percentage of every luminary. The procedure is applied to two inner spaces of the university building: a meeting room and a classroom, from the integration of MATLAB and GAMS. Results show the AECHIS for all possible alternatives and the description of the technical characteristics for the best control alternative. Also, it can be evidenced that the energy consumption by auxiliary components influences notably on sizing process because represents for majority of cases between 10% and 50% of AECHIS, the reason why the option with the highest controllability is not the best solution.