Use Of Electric Light Research Articles

Application of Artificial Intelligence in Stimulating Plant Growth Using Electric Lighting

This paper highlights the role of artificial intelligence (AI) in electric lighting for enhancing smart agriculture. The use of electric lighting in greenhouses is widely practiced in the present time, as sunlight is poorly available in some parts of the world. Different plants have different growth in different spectrum of light. The spectrum of light in which the plant grows maximum is coined as optimum growth spectrum (OGS). Hence, this study aims to choose artificial intelligence in assessing the optimum spectrum of light for a given plant. RGB based LEDs are used and its luminous efficacy is interpreted, considering different blend of mechanisms and the yield current and temperature. Rapid light fluctuations offered by pulse amplitude modulation causes a loss in the output of the LEDs. Hence, there lies a finite gap in the light provided and the light reaching the plant. Since, LEDs are the source of light here, hence, light sources complying with higher CRI should be deployed, as used in this experiment. The overall system was so designed such that when a plant is cultivated, using image processing, AI identifies the specific plant and implements all the available data, like the optimum growth spectrum, temperature, humidity, etc. The experiment clearly emphasizes on the results which were impressive. The OGS of the given plant has been figured out and trained the system through AI to execute the growth functions for the given plant.

Research note: Red light to mitigate light pollution: Is it possible to balance functionality and ecological impact?

The widespread use of electric lighting has revolutionised society but brought unintended consequences, notably light pollution, impacting ecosystems and human circadian rhythms. Concerns about anthropogenic light at night (ALAN) have prompted innovative solutions, such as spectral tuning of light sources. In Europe, a recent focus involves the enforcement of red light in outdoor settings to minimise ALAN’s impact, particularly on bats. This mini review synthesises literature to provide an overview of the advantages and disadvantages of the use of red light outdoors. There is a need for further examination of the potential ecological consequences of red light, considering challenges in lighting design functionality and broader impacts on diverse species.

Electrification of Department Stores in Paris (On the 175th Anniversary Since the Birth of P.N. Yablochkov)

The article describes the work of P.N. Yablochkov on the electrification of department stores in Paris. Before Yablochkov, department stores were illuminated with gas lamps, which were dangerous in terms of fire, distorted the colors of goods, and were harmful to health. The electric arc lamps existing at that time were difficult and expensive to operate, and had rather poor light quality. P.N. Yablochkov achieved outstanding results by bringing the color spectrum of his lamps closer to the solar one. The first project the Russian inventor implemented after he developed an arc candle was the lighting of the "Big Shops of the Louvre". Following this project, many large supermarkets in Paris began to install Yablochkov candles. Successful electrification of such significant social facilities contributed to the widespread use of electric lighting. The low cost and ease of maintenance allowed the Yablochkov system to successfully compete in the subsequent with incandescent lamps and other arc light sources. The article pays attention to the quality of Yablochkov's light. A significant contribution to the spread of the Yablochkov system was made by the outstanding French engineer and entrepreneur Louis Deneyrouz.

Implementation of machine learning techniques for the quasi real-time blind and electric lighting optimization in a controlled experimental facility

Machine Learning techniques have been recently investigated as an alternative to the use of physical simulations, aiming to improve the response time of daylight and electric lighting performance-predictions. In this study, daylight and electric lighting predictor models are derived from daylighting RADIANCE simulations, aiming to provide visual comfort to office room occupants, with a reduced use of electric lighting. The aim is to integrate an intelligent control scheme, that, implemented on a small embedded 32-bit computer (Raspberry Pi), interfaces a KNX system for a quasi-real-time optimization of the building parameters. The present research constitutes a step towards the broader goal of achieving a unified approach, in which the daylight and electric lighting predictor models would be integrated in a Model Predictive Control. A verification of the ML performance is carried-out by comparing the model predictions to data obtained in monitoring sessions in autumn, winter and spring 2020-2021, resulting in an average MAPE of 19.3%.

Electric light and the visualization of Catholic power in Spain during the Restoration Era (1874–1931)

This article analyses the contested adoption of electric lights by the Spanish Catholic church during the Bourbon Restoration era (1874–1931). Through a careful reading of primary sources, namely Catholic popular magazines, and official documents, it will show how Catholic authorities and practitioners resisted, negotiated and, ultimately, engaged with electricity in religious spaces. The article argues that electric light contributed to wider exchanges in a non-monolithic Spanish Catholicism on the observance of traditional values or the possibilities of the church’s modernization. However, amid a particularly tense moment regarding the secular–clerical relations, the systematic use of electric lights in churches at the turn of the twentieth century—but also in other public ceremonies—contributed to the making of religious sensations aimed at attracting new believers and reasserting the presence of the institution in a disputed public space.

Modernity of Electric Light and Shadow: Japanese Domestic Architecture from the Late 1910s to the Early 1930s

Electric light became popular as a source of illumination in Japan between the late 1910s and the early 1930s. It created novel sensory spaces that made the former darkness of domestic architecture a thing of the past. This article explores the ways in which domestic spaces became overwhelmingly lit by electric lights and how the architect Fujii Koji reacted to them in lighting and architectural design. The shift from embedded local illumination to general lighting entailed changing perceptions about indoor light conditions and how the light-body-space triad revolved around the rejection of interior darkness by electricity-related businesses, manufacturers, and academia. From the mid-1920s onward, this process was further enhanced by the Domestic Electricity Promotion Association, whose illumination planning, exhibitions, and model houses manifested its functionalist approach to effectively distributing light throughout the house, an approach subtly underpinned by a romantic vision of the domestic use of electric light. Functionalism in interior lighting, and the excessive brightness of electric light in domestic spaces, meanwhile, were questioned by Fujii and some lighting engineers. The disharmony between the glare of electric light and the Japanese style of rooms led him to create distinctive papered light fittings installed in his experimental houses, including Chōchikukyo. Fujii’s endeavours to scientifically understand and architecturalise diffused light through washi (Japanese paper) are conceptually similar to cultural critic Tanizaki Jun’ichiro’s In Praise of Shadows, an essay that rediscovered the systematically manipulable agents that produced Japaneseness: shadows in response to aesthetic discord caused by the emergence of electric light.

Association between Perceived Daylit Area and Self-reported Frequency of Electric Lighting Use in Multi-dwelling Buildings

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.

Ceiling and Wall Illumination, Utilance, and Power in Interior Lighting

The common use of electric lighting in interiors has led to the need to search for user- and environmentally-friendly solutions. In this research, the impact of the luminaires and room parameters on the selected parameters of general lighting in interiors was assessed. To achieve the objective of this work, a computer simulation and statistical analysis of results were conducted. The illuminance uniformity on work plane, ceiling and wall relative illuminances, utilance, and normalized power density of lighting installations for 432 situations were analyzed in detail. The scenarios were varied in terms of room size, reflectance, lighting class, luminaire downward luminous intensity distribution, and layout. The lighting class was a factor having the highest impact on ceiling and wall illumination, utilance, and power. It was also shown that the impact of lighting class on ceiling illumination, utilance and power, was different in interiors of various sizes. The impact of reflectances and luminaire layouts on the analyzed parameters was significantly lower. The results also demonstrated that the use of different lighting classes gave the possibility of reducing the power of general lighting in interiors at a level of 30% on average. Based on the results, a classification of energy efficiency in general lighting in interiors was also proposed. Understanding the correlations between the lighting system used and the effects achieved is helpful in obtaining comfortable and efficient lighting solutions in interiors.

Lock-in for lighting: The puzzle of continued kerosene use among electrified households in six Indian states

Electricity is the most commonly used form of energy for artificial lighting in modern society. Despite a rapid growth in the rate of electrification, 9% of electrified Indian households in our six sampled states continued to use kerosene as their primary lighting fuel in 2018. This appears as a puzzle considering the benefits of electric lights. Using a panel survey of rural households in six states in India, we examine why some grid-connected households primarily used kerosene lamps for illumination. We use a logistic regression model to test our hypothesis regarding the relationship between primary lighting choices and electricity quality. The results show that household primary lighting choices are correlated with nighttime duration of electricity service, daytime duration of electricity service, and the number of days without any electricity connection, at the 99% confidence level. Among these three factors, nighttime duration of electricity service has the greatest impact. To further promote the use of electric lights, intensive schemes to improve electricity quality are needed.

Residential electric lighting use during daytime: A field study in Swedish multi-dwelling buildings

This paper evaluates the effect of room function and orientation on daytime electric lighting use in dwellings, and the confounding role of room design aspects. A questionnaire survey was conducted in six multi-dwelling buildings including 75 apartments located in Malmö, Sweden (Latitude: 55.6 °N). Occupants were asked how often they use electric lighting during daylight hours, in three rooms of different functions, namely the kitchen, the living room and the bedroom. In a preliminary step, the behavior of occupants regarding electric lighting use was evaluated, to test whether design and orientation can affect switch-on behavior or whether it is random and unpredictable. In the next step, statistical analysis was performed to verify whether there is a relation between daytime electric lighting and room function, room orientation or both. Results indicate that electric lighting use did not vary significantly among occupants living in rooms of similar geometry, especially when living in West-oriented rooms. With respect to room function, overall it was shown that daytime electric lighting use was more frequent in kitchens. However, the study showed that electric lighting use in kitchens is associated with specific design features and not with room function per se. With respect to orientation, a consistent finding was that West-facing rooms use electric lighting less frequently compared to rooms of other orientations, and significantly less frequently compared to East-facing rooms, which can be explained by diurnal occupancy patterns characterizing residential spaces. The implications of the findings on daylight design criteria for residences are discussed.

The Role of Daylight for Humans: Gaps in Current Knowledge.

Daylight stems solely from direct, scattered and reflected sunlight, and undergoes dynamic changes in irradiance and spectral power composition due to latitude, time of day, time of year and the nature of the physical environment (reflections, buildings and vegetation). Humans and their ancestors evolved under these natural day/night cycles over millions of years. Electric light, a relatively recent invention, interacts and competes with the natural light–dark cycle to impact human biology. What are the consequences of living in industrialised urban areas with much less daylight and more use of electric light, throughout the day (and at night), on general health and quality of life? In this workshop report, we have classified key gaps of knowledge in daylight research into three main groups: (I) uncertainty as to daylight quantity and quality needed for “optimal” physiological and psychological functioning, (II) lack of consensus on practical measurement and assessment methods and tools for monitoring real (day) light exposure across multiple time scales, and (III) insufficient integration and exchange of daylight knowledge bases from different disciplines. Crucial short and long-term objectives to fill these gaps are proposed.

Early evening light mitigates sleep compromising physiological and alerting responses to subsequent late evening light

The widespread use of electric light and electronic devices has resulted in an excessive exposure to light during the late-evening and at night. This late light exposure acutely suppresses melatonin and sleepiness and delays the circadian clock. Here we investigate whether the acute effects of late-evening light exposure on our physiology and sleepiness are reduced when this light exposure is preceded by early evening bright light. Twelve healthy young females were included in a randomised crossover study. All participants underwent three evening (18:30-00:30) sessions during which melatonin, subjective sleepiness, body temperature and skin blood flow were measured under different light conditions: (A) dim light, (B) dim light with a late-evening (22:30-23:30) light exposure of 750 lx, 4000 K, and (C) the same late-evening light exposure, but now preceded by early-evening bright light exposure (18.30-21.00; 1200 lx, 4000 K). Late-evening light exposure reduced melatonin levels and subjective sleepiness and resulted in larger skin temperature gradients as compared to dim. Interestingly, these effects were reduced when the late-evening light was preceded by an early evening 2.5-hour bright light exposure. Thus daytime and early-evening exposure to bright light can mitigate some of the sleep-disruptive consequences of light exposure in the later evening.

Relation between daylight availability and electric lighting in a single-family house

Daylight availability is an important aspect that can potentially improve both the quality and the energy performance of buildings. However, it is not always straightforward easy to assure that an increase in the daylight availability leads to a reduction of electric energy use for artificial lighting. In this study, experimental measurements and numerical simulations were conducted to analyse the relation between the uses of artificial light and the daylighting availability for different groups of users who lived for one month each in a Zero Emission Building single-family house located in Trondheim, Norway. The use of electric lighting and the outdoor environment conditions (irradiance and illuminance on the horizontal plan) were recorded through advanced daylighting simulations, carried out with DIVA-for-Rhino, the daylighting availability during the periods of occupancy was then reconstructed, using as input data the outdoor environmental variable recorded during the experimental analysis. The results show that the coefficient of correlation between daylight availability and the artificial light is in general low and the use of artificial lighting seems to be largely independent from the availability of natural light.

The travelling lantern: the Courtois and Grandsart-Courtois family theatres as transcultural mediators at the nineteenth-century fair

ABSTRACTThis article discusses the lantern at the nineteenth-century fairground as a mobile but hidden technology and elucidates the role of this optical medium in the transnational circulation of visual culture by focussing on one particular but exemplary case: the Théâtre Courtois and the Théâtre Grandsart-Courtois. This Belgian fairground family travelled during five generations around European fairgrounds from the early nineteenth until the beginning of the twentieth century. Their programmes were very diverse, combining magic with science and technology, music, dance and acrobatics. On their travels they picked up new technological developments and ideas that were particularly suited for show business and introduced them in their shows: from projection with lanterns, through the use of electric light to the introduction of the cinematograph at Belgian, Dutch and French fairs. Relying on international fairground networks, they thus contributed to the circulation of visual culture between European cities and at annual fairs in smaller towns and villages. By considering these family theatres as actors of cultural transfer, and the lantern as a transcultural mediator, this article illustrates the variety and complexity of their mediating roles.

Minimum Daylight Autonomy: A New Concept to Link Daylight Dynamic Metrics with Daylight Factors

ABSTRACT Daylight metrics act as a useful tool to quantify the potential of natural light in an architectural space as well as the energy savings promoted by a suitable design of windows, atriums, and skylights. Accordingly, a new indoor lighting metric is proposed, minimum daylight autonomy, defined as the percentage of occupied time when an illuminance threshold can be met by daylight alone under continuous overcast sky conditions. This novel concept can determine an approximation of the maximum use of electric lighting and the quantification of minimum energy savings without the need for advanced calculation tools. Although daylight factor is the most widespread concept, it cannot forecast energy savings as accurately as dynamic metrics. In addition, daylight autonomy is the most usual dynamic definition, because it estimates the energy consumption of on–off electric lighting systems depending on weather conditions. However, there is no link between static and dynamic metrics, because both concepts are based on different variables. This research proposes the calculation procedure for minimum daylight autonomy, as well as the equations that serve to predict dynamic metrics based on static metrics, after confirming the accuracy of the simulation program that calculates the metrics using a test cell under real conditions.

Dimming strategies for open office lighting: User experience and acceptance

Sensor-triggered control strategies can limit the energy consumption of lighting by considering the presence of users in the office and dimming lighting down when it is not needed. In multi-user offices, the application of occupancy-based dimming at room level limits the energy saving potential. However, zone- or desk-based dimming may affect the comfort of co-workers due to its dynamics. This paper reports the assessment by 17 participants (30–50 years of age) of occupancy-based dimming in a mock-up office, using different dimming speeds. Participants consisted of co-workers experiencing changes triggered by others, and actors triggering these light changes. While the participants performed an office-based task, the luminaire above the actors’ desk was dimmed from approximately 550 lx to 350 lx (average horizontal illuminance), and vice versa. The participants evaluated the dimming conditions regarding their noticeability and acceptability. The study showed that the noticeability of light changes due to dimming, increases when fading times become shorter. Dimming with a fading time of at least two seconds was experienced as acceptable by more than 70% of the participants. The results of this experiment provide insights to system behaviour that does not compromise user experience while addressing energy efficient use of electric lighting.

Daylighting availability in a living laboratory single family house and implication on electric lighting energy demand

This study aims to analyze the correlation between daylight availability and the use of artificial light in a residential building in Nordic climate. Experimental data and numerical simulations are used to compare artificial light against daylighting availability. The use of electric lighting of six users’ groups and outdoor environment conditions were recorded. The daylight availability during the occupation periods has been reconstructed, using as input data the outdoor environmental variable recorded in experimental analysis. The results show that the coefficient of correlation between daylight availability and artificial lighting is low, and the artificial lighting only marginally depends on daylight availability.

Are Individual Differences in Sleep and Circadian Timing Amplified by Use of Artificial Light Sources?

Within the human population, there is large interindividual variability in the timing of sleep and circadian rhythms. This variability has been attributed to individual differences in sleep physiology, circadian physiology, and/or light exposure. Recent experimental evidence suggests that the latter is necessary to evoke large interindividual differences in sleep and circadian timing. We used a validated model of human sleep and circadian physiology to test the hypothesis that intrinsic differences in sleep and circadian timing are amplified by self-selected use of artificial light sources. We tested the model under 2 conditions motivated by an experimental study (Wright et al., 2013): (1) a "natural" light cycle, and (2) a "realistic" light cycle that included attenuation of light due to living indoors when natural light levels are high and use of electric light when natural light levels are low. Within these conditions, we determined the relationship between intrinsic circadian period (within the range of 23.7-24.6 h) and timing of sleep onset, sleep offset, and circadian rhythms. In addition, we simulated a work week, with fixed wake time for 5 days and free sleep times on weekends. Under both conditions, a longer intrinsic period resulted in later sleep and circadian timing. Compared to the natural condition, the realistic condition evoked more than double the variation in sleep timing across the physiological range of intrinsic circadian periods. Model predictions closely matched data from the experimental study. We found that if the intrinsic circadian period was long (>24.2 h) under the realistic condition, there was significant mismatch in sleep timing between weekdays and weekends, which is known as social jetlag. These findings indicate that individual tendencies to have very delayed schedules can be greatly amplified by self-selected modifications to the natural light/dark cycle. This has important implications for therapeutic treatment of advanced or delayed sleep phase disorders.

The effects of user interface designs on lighting use

PurposeThe purpose of this paper is to differentiate human responses to different light switch designs to determine the effects of these common interfaces on user perceptions and use of electric lighting in public buildings.Design/methodology/approachEmpirical studies were conducted to assess and examine user perceptions with regard to design characteristics of light switches, and occupants’ use of electric lighting was examined through field observations made in a public toilet.FindingsThe results point to the possibility of identifying characteristics of light switches that attract user attention and thereby encourage energy-saving behaviour in public buildings. A light switch perceived as simple but oversized affected occupants to turn off the lights more frequently when leaving the space under study as compared to switches of normal size.Research limitations/implicationsInformation on user perceptions of light switches may be limited by the assessments being carried out only in controlled environments. Assessing user perceptions in field observations is thus desirable, as it will provide more information on the perceptions in actual settings.Practical implicationsEffective design of user interfaces could provide a means of lowering energy use from electric lighting by affecting the behaviour of users. Using user perceptions to define critical design characteristics could contribute to design improvements in the interfaces with respect to users’ viewpoints.Originality/valueThis paper contributes to the subject with a basic, field-based approach to formulating an understanding of how design via user perceptions may encourage energy-saving behaviour.

Light at night, clocks and health: from humans to wild organisms.

The increasing use of electric lights has modified the natural light environment dramatically, posing novel challenges to both humans and wildlife. Indeed, several biomedical studies have linked artificial light at night to the disruption of circadian rhythms, with important consequences for human health, such as the increasing occurrence of metabolic syndromes, cancer and reduced immunity. In wild animals, light pollution is associated with changes in circadian behaviour, reproduction and predator-prey interactions, but we know little about the underlying physiological mechanisms and whether wild species suffer the same health problems as humans. In order to fill this gap, we advocate the need for integrating ecological studies in the field, with chronobiological approaches to identify and characterize pathways that may link temporal disruption caused by light at night and potential health and fitness consequences.