Light Usage Research Articles

Artificial illumination identification from an unmanned aerial vehicle

Artificial illumination identification within images is a useful tool for many applications. Performing such identification allows for an estimation of the illumination source spectrum, which in turn can be used for additional applications ranging from spectral detection and exploitation to statistics about nighttime light usage. Illumination identification has been performed in laboratory settings but not from an unmanned aerial vehicle (UAV) platform. Here, we test the feasibility of using a UAV and commercial off-the-shelf multispectral imaging sensor to perform such artificial illumination identification through linear discriminant analysis using nighttime UAV images. The results are very promising, showing source classification accuracies of 83.3%, 92.3%, 100%, and 100% for the incandescent, light-emitting diode, high pressure sodium, and metal halide illumination sources, respectively. We show that the information gained from the source identification can be further used to inform additional analysis, such as spectral identification. The high resolution of UAV imaging techniques combined with the knowledge of the illumination source can lead to better exploitation of such nighttime data for many applications.

Prospect of achieving net-zero energy building with semi-transparent photovoltaics: A device to system level perspective

Since buildings consume a large portion of electricity worldwide, several technologies have been under research to reduce their energy demand and the carbon footprint. Semi-transparent photovoltaics (STPV) which transmits visible light yet, at the same time, produces electricity has most likely the highest potential to achieve this goal. The purpose of this paper is to find whether STPV – at its fundamental limit – can achieve net-zero energy building. We consider silicon based non-wavelength selective STPV and develop thermodynamic models for electrical, optical and thermal parameters. Based on this model, we estimate yearly net energy footprint of an office building for various climatic conditions. Building energy simulation is performed using EnergyPlus, combined with power generation calculation from a solar irradiance model. Our results suggest that for 50% visible transmittance, STPV on clear glass saves about 50% and 30% of the energy demand in tropical and hot desert regions respectively and around 20%–25% in Scandinavian and cold continental regions. When combined with a low-emissivity glass, the net saving reaches as high as 90% in tropical regions, 60% in hot desert regions and 45%–70% in the rest of the regions. We propose device and system level figures of merit that take into account usage of natural light as well as overall energy saving. The figures of merit capture the trade-offs between efficiency, solar heat gain and transparency and predict a much lower optimum transparency for places with abundant sunlight. We show that the low net saving for these hot regions can be improved to nearly 100% if such optimization strategies are adopted. This makes STPV, combined with low-emissivity glass, a promising technology across the globe.

Comparative Assessments of CFLs, Incandescent and LEDs Bulbs for Energy Efficient Lighting System in Building

Compact Fluorescent Lamps (CFLs) and Light Emitting Diode (LEDs) are fast replacing incandescent bulbs in most residential buildings because they are designed to fit into most lamp holders originally designed for incandescent bulbs. The aim of this work is to look at to what extent the usage of Compact Fluorescent Lamps (CFLs) or Light Emitting Diode (LEDs) can help reduce energy demand and how energy wastage in residential buildings due to lighting can be addressed by using energy efficient lamps. Energy meter was used to measure the actual energy in kWh (kilowatt-hour) of each bulb. Lux meter was used to measure the luminance (brightness) between CFLs, LEDs and Incandescent bulbs. Lighting point calculation for a three bedroom flat was carried out and the number of lighting points required to light up the building was calculated. An estimate of energy consumed for one year by the different bulbs using the readings from the energy meter was done and the prices of the bulbs was compared to ascertain if the cost outweighs the energy consumption. The prices of incandescent bulbs when compare to CFLs and LEDs in local stores is far cheaper than CFLs and LEDs with a burden of huge cost in lighting the incandescent bulbs due to energy wastage. Lighting design calculation for a three bedroom flat was carried out using IES (Illuminating Engineering Society) recommendation for different area. It was observed that LEDs bulbs can save almost 86.4% energy consumed by Incandescent bulbs while using CFLs bulbs can save 78.8% energy consumed by incandescent bulbs. Hence, LEDs is the most energy efficient bulb, by using LEDs in every home there will be a reduction of over 80% energy consumption due to lighting when compared to incandescent. DOI: 10.7176/JETP/10-5-04 Publication date: September 30 th 2020

Triboelectric Nanogenerator technology potential in agricultural LED lighting

Nanogenerator Technology is gaining more and more popularity among the scientist society. The triboelectric nanogenerators in particular already are used in different industries. The aim of the work was to see the achievements in the field, and what the state of art of triboelectric technology can offer to solve some of the problems agriculture industry is facing today. A way to implement the technology to a greenhouse was introduced in the work, to reduce the cost for the usage of LED lighting in the greenhouse. It was calculated that triboelectric nanogenerator system that is a kilometre long and a metre wide can potentialy support LED lighting in a greenhouse with an actual area of coverage of more than 650 hectares. The actual numbers are expected to be very different since there are no evidences of the technology being implemented at this stage of its development into the agriculture as a LED energy source. The system was suggested to be made near a busy motor way to convert the kinetic energy of the cars into the electrical power. The system is expected to have many advantages over the conventional electromagnetic power generating system, but due to obvious disadvantages of the dependence of the energy generated on the traffic, the technology is suggested best to be used in combination with electricity from public network.

Synthesis of Pyrrolo[2,1,5-cd]indolizine Rings via Visible-Light-Induced Intermolecular [3+2] Cycloaddition of Indolizines and Alkynes.

A range of indolizine smoothly underwent visible-light-induced intermolecular [3+2] annulations with internal alkynes to afford pyrrolo[2,1,5-cd]indolizine in good to excellent yields with high regioselectivity. Through this cascade reaction, a series of fluoroactive fused indolizines with a large π-system were conveniently synthesized. The usage of visible light as energy source with air as a stoichiometric oxidant under simple conditions makes this process attractive and practical.

Feelings of guilt and pride: Consumer intention to buy LED lights.

The adoption of energy-efficient lighting systems such as light-emitting diode (LED) lights is an effective strategy to address global warming and climate change. The adoption of LED light usage is largely shaped by consumer behavior. Understanding the factors that influence consumers’ awareness of the advantages of using LED lights and consumers’ eventual buying behavior is critical to industry players and policy-makers. The objective of this study is to investigate the significant factors that affect consumer intention to use LED lights among Malaysian households. A survey questionnaire of 1,075 potential consumers was employed and the partial least squares technique was applied in data analysis. The results show that consumer awareness creates responsibility and influences consumers’ personal norms and attitudes, and their ultimate intention to buy LED lights. Feelings of guilt about contributing to air pollution and an awareness of the advantages of using LED lights both activate individual personal norms and attitudes, and influence the intention to buy LED lights. Awareness of the advantages of using LED lights, and of the negative consequences of not using them, prompts consumers to have feelings of guilt. The findings point to the importance of creating awareness among consumers.

Quantitative changes in DNA methylation induced by monochromatic light in barley regenerants obtained by androgenesis

Changes in DNA methylation are one of the best known mechanisms of epigenetic regulation of gene expression, which in the process of induced androgenesis is associated with reprogramming of haploid microspores development towards the formation of embryos, as a result of exposure of anthers in ears and then anthers culture in vitro to stress factors. The aim of the study was to test the hypothesis of whether the use of monochromatic light during induced androgenesis might be associated with epigenetic phenomena. The experiments were carried out on DH plants of spring barley (Hordeum vulgare L.) obtained by androgenesis modified by monochromatic light: blue, green and red. A quantitative evaluation of the effect of light on the degree of DNA methylation was performed using RP-HPLC for the comparison of regenerants obtained under standard, control conditions (darkness) with those obtained with light usage. The differences in the amount of methylated cytidine in comparison to the control were: 0.40%, 0.16% and -0.55%, for blue, red and green light, respectively. The level of global genomic DNA methylation from control plants was in the range 21.32-21.52%. Methylation changes in response to monochromatic light used during callus formation in anthers culture, determined by RP-HPLC, are significant although small.

Design and Simulation of MPPT Control for Solar Powered AC Autonomous LED Lighting Applications in MATLAB Simulink Environment

As an AC LED light applications have become a commonplace item of light industry, it has a wide range of usage in garden lighting, cove lighting, office lighting and retail applications. The paper brings out the utilization of Boost converter along with Maximum Power Point Tracker (MPPT) technique for the control of Photovoltaic power. This proposed system which includes Boost converter, a single phase full bridge inverter with Sinusoidal Pulse Width Modulation (SPWM) technique. The main concept of this converter includes designing of boost converter that provides an output voltage of 350V DC and single phase SPWM provides 350V, pure sine wave output (230V RMS) applicable to AC autonomous LED Lighting system. In order to bring out a transformer free inverter, the designed boost converter is simulated in the MATLAB Simulink software and the results are shown with low THD as per IEEE standard, with acceptable power factor and higher efficiency.

Computational Model of Sclerotic Scatter.

A clinical examination technique to detect pathology within the anterior eye is known as "sclerotic scatter" (SS). Its propagation pathway has not been thoroughly investigated. Although conventionally theorized to occur by "total internal reflection" (TIR) within the cornea, existing data suggest that this may be an incomplete explanation. An anterior eye model representative of a human eye has been constructed using nonsequential ray tracing (OpticStudio 18.1). Three generations of the model were constructed to support the analyses of the pathway of light in SS. A design of experiment methodology involving the key parameters was used to determine the slit-lamp setup for optimum clinical visualization. Most of the light directed into the temporal limbus in SS is lost (52%) into the sclera or reemitted back to the clinician. Only 0.006% of light that transits the central cornea undergoes TIR off the anterior cornea and more significantly 0.000125% off the posterior cornea. The optimal slit-lamp setup parameters to maximize the clinician's visualization are also summarized. The propagation of light within SS primarily does not occur by TIR off the posterior cornea but rather the direct transcameral propagation of light. SS also represents an inefficient usage of light, with approximately half of the light creating a potential glare source for clinicians. We have formulated a recommended set of parameters for the slit-lamp setup to maximize clinical visualization. We also describe the transcameral pathways involved in SS that create a corneal "backlighting" effect. Almost a century after Graves original description, the optics of this phenomenon are described here.

Morphological, Structural and Optical Characteristics of Porous GaN Fabricated by UV-Assisted Electrochemical Etching

The fabrication of porous GaN (PGaN) by UV-assisted electrochemical etching with a variations of current densities (40, 60, and 80 mA/cm2) for 60 min in electrolytes consisting of 4% KOH are reported. Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-Ray (EDX), Atomic Force Microscopy (AFM) and X-ray Diffraction (XRD) were used to characterize the morphological and structural characteristics of the PGaN. All PGaN sample prepared by electrochemical etching technique produced a hexagonal-like pore shape. FESEM images demonstrated that the pore uniformity and porosity are affected significantly by the current density. The PGaN sample fabricated with 80 mA/cm2 produces a uniform and high porosity structure compared to other PGaN sample. This shows that the morphology and structural characteristic of PGaN are increase with the increase of current density. The EDX result revealed significant Ga and N atom presence in all samples. However, the O atom only presence in sample etched with 80 mA/cm2 implying that the etching process is occur vigorously in this sample. The AFM verified that the surface roughness and the pore depth are increased as current density increased. There were relatively large variations of the peak intensities for 2Theta-scan patterns as exposed by XRD. The peak shift for PGaN sample relative to as-grown was inconsistent and the changed was relatively small. Raman intensity found to be enhanced with the increase in current density and among the PGaN sample, the E2(high) peak for sample prepared with 60mA/cm2 and 80mA/cm2 was observed to be slightly shifted to lower frequency. The PL spectra displayed that the porosity has high impact on the PL peak intensity. . Overall, this proved that with the usage of low power UV light, the pore structure still can be produced as good as pore structure fabricated with high power UV light.

Lighting User Experience (LUX) Cards: A Card-based Tool for the Design of Smart Lighting Solutions

Lighting User Experience (LUX) Cards: A Card-based Tool for the Design of Smart Lighting Solutions

Peroxymonosulfate enhancing visible light photocatalytic degradation of bezafibrate by Pd/g-C3N4 catalysts: The role of sulfate radicals and hydroxyl radicals

For efficient usage of visible light, Pd loading graphitic carbon nitride (Pd/g-C3N4) hybrids were synthesized and peroxymonosulfate (PMS) was accompanied to improve the photoactivities of Pd/g-C3N4. The photocatalytic system consisting of Pd/g-C3N4, PMS and visible light (Pd/g-C3N4-PMS-Vis) exhibited higher bezafibrate (BZF) removal efficiency than Pd/g-C3N4-PMS, Pd/g-C3N4-Vis, g-C3N4-PMS, g-C3N4-Vis, and g-C3N4-PMS-Vis systems, which can be ascribed to the electron transfer from Pd/g-C3N4 to PMS. Density functional theory (DFT) calculation proved that the chemical bond interaction forming between Pd and g-C3N4 inspired the electron excitation, separation and transportation. Meanwhile, Pd particles with local surface plasma resonance (LSPR) phenomenon could also enhance the visible light adsorption. Notably, the photocurrent response of Pd/g-C3N4 was significantly improved with PMS, demonstrating the photoinduced electrons on Pd/g-C3N4 are capable to immigrate to PMS. The added PMS can perform as electron acceptors, thus favoring the quantum efficiency of photoinduced charge carriers to form SO4−. The BZF degradation mechanism was clarified by the addition of different scavengers and the major reaction active species were hydroxyl radicals (OH) and sulfate radical (SO4−). Four possible pathways in the degradation of BZF were also put forward via LC-MS/MS analysis (R-oxy substituent, oxidation dichlorination, OH-addition and oxidation deaminization). In the 2%Pd/g-C3N4-PMS-Vis system, an obvious decrease of genetic toxicity was observed because of the high removal efficiency and final low concentration of BZF. The results of this research underlined great prospective of Pd/g-C3N4 catalysts and provided a potential approach to photocatalytically remedy the polluted water by micropollutants.

Design of differentiated warranty coverage that considers usage rate and service option of consumers under 2D warranty policy

Warranty service providers usually provide homogeneous warranty service to improve consumer satisfaction and market share. Considering the difference of consumers, some scholars have carried out studies on maintenance strategies, service pricing, payment method, claim behaviour and warranty cost analysis in recent years. However, few scholars have focused on the differentiated coverage of warranty service that considers usage rate and service option of consumers. On the basis of previous classification criteria on usage rate, this paper divides consumers into heavy, medium and light usage rate groups with clear boundaries. To avoid discrimination in warranty service, this study divides 2D warranty coverage into disjoint sub-regions and adopts different maintenance modes in each sub-region. By formulating and calculating warranty cost model under warranty cost constraints, we can obtain the maximum warranty coverage under usage rate \begin{document}$ r $\end{document} . Therefore, differentiated warranty scope for consumers in the three groups can be proposed, whilst consumers can choose the most suitable warranty service according to their usage rate. Evidently, the proposed warranty strategy can provide flexible warranty service for consumers, meet the requirements of the warranty cost constraints of warranty service providers and enable enterprises to occupy a favourable position in the market competition.

Analysis of photoreactivity and phototoxicity of riboflavin's analogue 3MeTARF

Recent studies focus on usage of blue light of λ = 450 nm in combination with photosensitizers to treat surface skin disorders, including cancers. In search of convenient therapeutic factor we studied riboflavin analogue 3-methyl-tetraacetylriboflavin (3MeTARF) as potential sensitizer. Riboflavin (Rfl) itself, non -toxic in the darkness, upon absorption of UVA and blue light, may act as photosensitizer. However, Rfl efficiency is limited due to its susceptibility to photodecomposition. Riboflavin's acetylated analogue, 3MeTARF, bears substituents in ribose chain, which inhibit intramolecular processes leading to degradation. Upon excitation, this compound, reveals higher photochemical resistance, remaining a good singlet oxygen generator. Thus, being more stable as the sensitizer, might be much more efficient in photodynamic processes. The objective of undertaken study was to elucidate mechanisms of 3MeTARF photoreactivity under the irradiation with blue light in comparison to its mater compound, riboflavin. We approached this goal by using spectroscopic methods, like direct singlet oxygen phosphorescence detection at 1270 nm, EPR spin trapping and oximetry. Additionally, we tested both riboflavin and 3MeTARF phototoxicity against melanoma cells (WM115) and we studied mechanism of photodynamic cell death, as well. Moreover, 3MeTARF induces apoptosis in melanoma cells at ten times lower concentration than riboflavin itself. Our studies confirmed that 3MeTARF remains stable upon blue light activation and is more efficient photosensitizer than Rfl.

The Arctic picoeukaryote <i>Micromonas pusilla</i> benefits from ocean acidification under constant and dynamic light

Abstract. Compared to the rest of the globe, the Arctic Ocean is affected disproportionately by climate change. Despite these fast environmental changes, we currently know little about the effects of ocean acidification (OA) on marine key species in this area. Moreover, the existing studies typically test the effects of OA under constant, hence artificial, light fields. In this study, the abundant Arctic picoeukaryote Micromonas pusilla was acclimated to current (400 µatm) and future (1000 µatm) pCO2 levels under a constant as well as a dynamic light, simulating more realistic light fields as experienced in the upper mixed layer. To describe and understand the responses to these drivers, growth, particulate organic carbon (POC) production, elemental composition, photophysiology and reactive oxygen species (ROS) production were analysed. M. pusilla was able to benefit from OA on various scales, ranging from an increase in growth rates to enhanced photosynthetic capacity, irrespective of the light regime. These beneficial effects were, however, not reflected in the POC production rates, which can be explained by energy partitioning towards cell division rather than biomass build-up. In the dynamic light regime, M. pusilla was able to optimize its photophysiology for effective light usage during both low- and high-light periods. This photoacclimative response, which was achieved by modifications to photosystem II (PSII), imposed high metabolic costs leading to a reduction in growth and POC production rates when compared to constant light. There were no significant interactions observed between dynamic light and OA, indicating that M. pusilla is able to maintain effective photoacclimation without increased photoinactivation under high pCO2. Based on these findings, M. pusilla is likely to cope well with future conditions in the Arctic Ocean.

Indoor Navigation System for Vision Impairment People through Visible Light Communications

Indoor navigation is opportune for everyone, and it is particularly requisite for the visually impaired. The paper proposes an indoor navigation system for the Visually Impaired to attain audio output through visible light communications. The transmission of data occurs after identifying the person who has entered the room and the technology light fidelity is used for presenting information to the user. Light fidelity technology is used by the proposed system for the wider range of transmission of data. The usage of visible light for transmitting the data encompasses a wide variety of advantages and eliminates most problems of communication caused by the electromagnetic waves outside the visible spectrum. Light fidelity technology is an evolving branch of Optical Wireless Communication and can be beneficial in coming years for indoor communication because it can afford higher data rate transmission along with the capability to utilize additional users since it uses a broader spectrum bandwidth. The main idea of our project is to create internal navigation system by using Arduino software and Arduino hardware. The transmission of data can act as transceiver, where LED and solar cell are used as the medium to transmit and receive the data.

Temperature Field Measurement in a Cutting Tool by Laser Interferometry

To increase machining efficiency, in addition to determining the temperature distribution on the tool surface, it is also necessary to determine the internal temperature distribution. The existing methods for determining the cutting tool temperature distribution and temperature field measurement have significant disadvantages, which limit their applicability and accuracy. The purpose of this study is to develop and test a novel cutting tool temperature field measurement method. The method involves recording the cutting tool thermal expansion fields by laser interferometry and calculating the tool material temperatures with its coefficient of thermal expansion (CTE). Compared with the methods employing infrared thermometry, the method developed in the present study has a higher spatial resolution and a lower achievable field of view due to its usage of light in the visible region. In addition, since the oxidation film has a higher reflection coefficient for visible light, the present method is less sensitive to the thin-film interference on an oxidized tool surface than those using infrared thermometry, eliminating the false shift of the measured temperature. Moreover, by utilizing cheaper optical components and equipment for interference fringe pattern registration, this method is more affordable. Unlike the emissivity coefficient in infrared thermometry, CTE is independent of changes in the surface quality and can be measured with high accuracy by modern dilatometry. Therefore, the developed method, which employs CTE to calculate the temperature, has a higher reliability. In the present study, the efficiency of this method is tested by the orthogonal turning of difficult-to-cut martensitic heat-treated steel with a cemented tungsten carbide tool. Through the experiment, the temperature distributions along the rake face and flank of the tool, as well as the temperature field inside the tool, were obtained. The results can improve the temperature field measurement in machining cutting tools.

Decreasing Usage of Lights and Sirens in an Urban Environment: A Quality Improvement Project.

Introduction:The risk of lights and sirens use in emergency medical services has been well documented. Our critical care transport team performs over 1,800 interfacility nonemergency medical services transports annually into a dense urban environment. Historically, we have utilized lights and sirens to navigate traffic patterns. The use exceeded industry standards. This quality improvement project was undertaken to decrease the use of lights and sirens.Methods/Results:The baseline use of lights and sirens in 2011 was 76% en route and 73% on return to the facility. We revised the internal policy guiding the appropriate usage of lights and sirens. In 2012, without an improvement in usage, a use justification process was implemented. By 2013, the use of lights and sirens was still high en route, but had decreased to 53% on the return trip. In 2014, we added accountability measures requiring justification, with a subsequent drop in 2015 to 14% en route and 13% on return. In the following 3 years, the transport teams have sustained lights and sirens use to 20% or below.Conclusions:This quality improvement initiative impacted team behavior and decreased the use of lights and sirens over 5 years, with sustained improvement at or below 20%. This improvement was accomplished through ongoing evaluation, education, data gathering, and open communication. There was no negative impact on patient outcomes during this time. Lights and sirens continue to be used when indicated.

Impressions of remote area electrification on social and economic indicators

The development of any country depends on the electrification of rural regions as most of the population is residing in rural areas. Development is counted in terms of per capita energy consumption as well as even distribution of electricity. This paper presents an investigation of the impact of rural electrification on lighting, studying, energy expenditure, and income. Data has been collected from southern region rural villages. Some villages are connected and some are non-connected with the grid. To estimate the decision probability of getting connected from households, electrified and non-electrified villages are evaluated. These observations are used to determine the impact of electrification of rural areas on resultant indicators. The authors observed a minor positive effect on home study and income, whereas a major effect on lighting usage. Finally, the potential improvements in the socio-economical status of rural people by improved lighting are highlighted.

Wind Energy Application for Small Business

This Paper is about application of RENEWABLE energy i.e. Wind energy for less power consumption in small scale business at seashore. Beach Hotels consumes a heavy amount of power due to usage of Light, Fan, Television, bulb and other electrical equipments. Generally, this power is taken from Transmission lines (Over Head Lines). At the seashore, wind is available at huge scale. So, we can use this wind energy for electricity generation and can make it use so that we can save commercial energy as much as possible. In this paper we are going design small wind turbine to utilize wing energy for driving electrical appliances in Hotels.