Outdoor Lighting Research Articles

МЕТОДИКА ВЕРОЯТНОСТНОЙ ОЦЕНКИ ЭЛЕКТРОПОТРЕБЛЕНИЯ (ВОПРОСЫ ЭНЕРГЕТИЧЕСКОЙ БЕЗОПАСНОСТИ И ПРАВОВОГО ОБЕСПЕЧЕНИЯ)

The article deals with the problem of determining the actual energy consumption of outdoor lighting in municipalities, which arises as a result of the shortcomings of the existing energy management system and leads to contradictions between electricity suppliers and the municipality. The lack of metering devices and a wide variety of types of lighting lamps leads to the fact that the standard calculation methods used by the supplier unreasonably overestimate the cost of real consumption, thus limiting the budgetary possibilities of cities. It is proposed to solve this problem through the use of rank-parametric tools, which are successfully used for evaluation and forecasting in industry.

Air and Thermally Stable Fluoride Bridged Rare-Earth Clusters Showing Intense Photoluminescence and Potential LED Application.

Fluoride based lattice is attractive for reducing phonon-induced quenching in rare-earth (RE) based luminescent materials. However, due to the strong affinity betweenRE and oxygen, the synthesis of fluoride-based complexes has to be protected under anhydrous conditions,and many known fluoride bridged RE clusters are unstable in air. Here, by using the "mixed-ligand" strategy a family of fluoride bridged RE clusters is synthesized, namely RE16(μ4-F)6(μ3-F)12(tBuCOO)18[N(CH2CH2O)3]4 (RE = Eu, EuFC-16; RE = Tb, TbFC-16), which are highly stable in air and decomposed thermally only when heating above 435°C. Moreover, both clusters exhibit high photoluminescence quantum yields (PLQYEuFC-16 = 87.7%, PLQYTbFC-16 = 99.0%). Upon warming, EuFC-16 and TbFC-16 displayexcellent structural, thermal, and chroma stability. Thus, EuFC-16 and TbFC-16 have the potential to be used in light-emitting diode (LED) devices, offering many advantages over commercial phosphors. First, both clusters are soluble in UV-curable resin at any mixing rate, and the emission colors can be tuned from magenta, turquoise, willow green, and ivory to pure white if mixing blue phosphor BAM:Eu2+. Second, the clusters are hydrophobic, and the LEDs work well after soaking in water, indicating a good quality for outdoor lighting.

National Park visitors perceive benefits for themselves and wildlife under blended red-white outdoor lighting

Visitors to Colter Bay Village in Grand Teton National Park were surveyed to elicit their evaluations of experimental outdoor lighting conditions. Luminaires capable of dimming and switching between two LED modules (white, blended red-white) were installed in street and parking areas. The blended red-white lamps consisted of 30 narrowband LED with a peak wavelength 623 nm and two 3000 K white LEDs. Similar “red” lamps were previously shown to reduce impacts to bats and insects. The white and red lamps were closely matched for luminance. Measured horizontal illuminance at survey locations had an interquartile range from 0.63 to 3.82 lx. The red lamps produced lower perceived brightness (VB2(λ)), even after reflection off asphalt, yet survey participants expressed higher ratings for visual comfort and safety under red lighting. Surveys conducted earlier in the evening, with higher levels of predicted solar and measured horizontal illuminance, rated higher on visual comfort and safety, though these correlations were not as strong as the effect of lamp color. Streetlight ratings and support for lighting that protected natural resources were not contingent upon age or gender. Survey participants assessed red lighting as more protective of the environment. These results demonstrate that outdoor lighting designed to reduce ecological impacts can yield superior nocturnal experience for pedestrians.

Cool white light emitting Dy3+ activated KNaCa2(PO4)2 phosphor for outdoor lighting and optical thermometric applications

Dy3+ incorporated KNaCa2(PO4)2 phosphor (KNCP) with doping concentrations ranging from 0.005 to 0.7 mol were synthesised via high-temperature solid state reaction route. The morphological characteristics were examined using FESEM images and found agglomerated structure in micrometers with an average particle size of 4.037 µm. Photoluminescence emission spectra under 350 nm excitation reveal nearly equal intense blue and yellow emission bands owing to 4F9/2→6H15/2 and 4F9/2→6H13/2 Dy3+ transitions, respectively. The concentration-dependent emission properties were examined and the optimum concentration was found to be 0.03 mol. The synthesized phosphor exhibits a quantum yield of 69.06 % at the optimal Dy³⁺ doping concentration. The time-correlated emission characteristics were analysed from the TRES plot. Furthermore, the emission bands at 479 nm (4F9/2→6H15/2) and 572 nm (4F9/2→6H13/2) under 350 nm excitation follow bi-exponential decay having an average lifetime in the range of 0.90–0.37 ms. The prepared phosphors exhibit an intense cool white light regardless of doping concentration and delay time. Optical thermometric properties of KNCP Dy phosphor were investigated by fluorescence intensity ratio (FIR) technique and exhibit relative thermal sensitivity of 2.57 and 0.7 %K−1 in the temperature range of 90 −230 K and 250–500 K respectively. The excellent quantum yield, sub-millisecond lifetime, cool colour temperature, and higher temperature sensitivities make them ideal for outdoor lighting and optical thermometric applications.

Impact of dispensing optical, nonoptical, and electronic devices on the visual function of students attending the schools for the blind

Background: Many students attending schools for the blind have some vision that can be made use of to improve their vision function. Aims: Our study aimed to assess the impact of optical, nonoptical, and electronic devices on vision function of visually impaired students. Setting and Design: This prospective interventional study was conucted in schools for the blind in western Maharashtra, India. Methods: Students attending schools for the blind were evaluated with history-taking, visual acuity tests, ocular examinations, fundoscopy, and low vision workup in 2022–2023. The LV Prasad Functional Vision Questionnaire assessed impact on vision function, before and after 3-month adaptation period. Results: Five hundred and thirty-five students aged 5–25 years with visual acuity <6/60 in the better eye from eight schools were evaluated. Among them, 172 (31.77%) received low vision aids, with 144 (84.70%) using nonoptical devices such as NoIR filters, Caps, Typo scopes, and White canes. Optical devices such as telescopes and magnifiers in 35 and electronic devices like portable video magnifier in 11 students. Forty-six received all three types. There was a significant enhancement (P < 0.001) in tasks related to distance, near vision, mobility, and outdoor lighting conditions for students using nonoptical devices alone or combined with optical aids and video magnifiers. Among the 119 (70%) students using nonoptical devices, 80 (67.22%) exclusively used them, while 42 (32.77%) combined them with other aids, showing even more substantial improvement. Conclusion: Optical, nonoptical and electronic, when used together improved vision function of visually impaired students.

Estimating SPAD, Nitrogen Concentration, and Chlorophyll Content in Rice Leaves using Calibrated Smartphone Digital Image

Laboratory analysis is commonly used to determine nitrogen and chlorophyll content. However, smartphones can serve as rapid, mobile, and non-destructive tools for this purpose. An equation can be created to calculate nitrogen and chlorophyll content by analyzing color parameters from digital images of rice leaves. An examination was performed on 86 rice leaf samples from the maximum tillering and mature stages. Rice leaf photos were taken with a smartphone in natural outdoor lighting. Color calibration with Spydercheckr was needed to adjust for lighting conditions. Uncalibrated and calibrated image data were analyzed to determine RGB values converted into CIELAB color space. The L*, a*, and b* values had a significant correlation with SPAD parameters, nitrogen concentration, chlorophyll a, b, and total chlorophyll content. This connection was higher after image calibration. The study found that smartphone images could predict SPAD values with 87.9% to 92.3% precision, depending on color space. Using a smartphone digital picture of L* and a* values, N content could be estimated with 84.7% and 81.9% accuracy. Average accuracy for chlorophyll a, b, and total chlorophyll content was 65% to 76%. This study shows smartphone images can estimate rice leaf SPAD and nitrogen content.

Evaluation of a cost-effective photoelectric sensor for daylight harvesting in smart public lighting systems

Global warming concerns, along with international agreements and regulations, reflect a broader effort to change the public's high energy demand in recent years. Smart public lighting systems are gaining popularity due to their energy-saving capabilities, reduction in carbon dioxide emissions, and improved public comfort. However, transitioning to smart public lighting requires careful planning and multiple stages. This is not only to accommodate public behavior, revise scenarios, and test citizen acceptance but also due to the necessary infrastructure investments. Smart public lighting incorporates new technologies, often with a breakeven point that takes several years to reach. To promote the widespread adoption of smart public lighting, it is essential to produce relatively expensive components in large quantities and explore cost-effective solutions. This research focuses on investigating a cost-effective photoelectric sensor for smart public purposes. The primary originality of this study lies in identifying a cost-effective photoelectric sensor that can replace technically equivalent but more expensive sensor solutions for indoor and outdoor lighting control purposes.

Virtual home staging and relighting from a single panorama under natural illumination

Virtual staging technique can digitally showcase a variety of real-world scenes. However, relighting indoor scenes from a single image is challenging due to unknown scene geometry, material properties, and outdoor spatially-varying lighting. In this study, we use the High Dynamic Range (HDR) technique to capture an indoor panorama and its paired outdoor hemispherical photograph, and we develop a novel inverse rendering approach for scene relighting and editing. Our method consists of four key components: (1) panoramic furniture detection and removal, (2) automatic floor layout design, (3) global rendering with scene geometry, new furniture objects, and the real-time outdoor photograph, and (4) virtual staging with new camera position, outdoor illumination, scene texture, and electrical light. The results demonstrate that a single indoor panorama can be used to generate high-quality virtual scenes under new environmental conditions. Additionally, we contribute a new calibrated HDR (Cali-HDR) dataset that consists of 137 paired indoor and outdoor photographs. The animation for virtual rendered scenes is available here.

Making Solar PV Street Light – A New Convention

Today’s society is completely based on fossil fuels directly or indirectly for every aspect of its existence. The transformation from fossil fuels to green energy is essential for coming decade to mitigate sudden climate change and most importantly to ensure long term sustainability. Though this shifting works well in theory, but the reality is that shifting from fossil fuels is not so easy as it is considered to be most available convenient source of energy. Sustainable solution with modern creative ideas embedded with traditional practices, can reduce the dependency on fossil fuels on everything from energy to infrastructure. Today Light emitting diode (LED) lamps have replaced High intensity discharge (HID) lamps that were used at urban street light. Solar Street lights work on the principle of photovoltaic cell or solar cell. This paper presents an overview of the design and implementation of the solar PV street lights as a new convention in outdoor lighting technology. Solar PV Street lights eliminate the need of grid electricity, making it cost effective and environment friendly in urban and rural areas. The system’s components include solar panel, batteries, light sources, charge controllers and a pole structure. In short, this paper is based on the idea of maintaining the maximum utilization and minimum loss of available energy and also making an approach to increase the longevity of the system’s components with some common techniques and make a shift from conventional to non-conventional source of energy and thus a new convention is proposed.

ENERGY CONSUMPTION AS AN INDICATOR OF ECONOMIC GROWTH

Energy - is manifested in the provision of various needs of people. We can add daily individual needs such as food, heating, communications, transportation, education, and social conditions. Social needs cover such broad areas as safety, clean water delivery, outdoor lighting, waste management, education, and health care. In other words, energy is a requirement at every stage, from the production of all the needs we have mentioned to their distribution. Since energy is a limited and depleted factor of production, it is indispensable for social development. Today, its careful and efficient use is essential and the subject of various studies. In particular, much attention is paid to environmentally friendly renewable energy sources. On the other hand, the growing energy demand, which is one of the essential factors affecting countries' economic growth, remains relevant. Economic growth - reflects an increase in the level of national income and per capita income. Since ensuring economic growth is one of the main goals of countries, each country wants to ensure its own energy independence or sustainable energy reserves. In providing economic growth, not only the amount of energy used is of great importance, but also the efficient use of energy to increase production. It should be carefully emphasized that an increase in energy consumption not only leads to economic growth but, as a result of economic growth, more energy is consumed. In other words, in each case, more energy consumption is needed to achieve the economic growth that countries aim for, and the energy infrastructures and resources required for economic growth must be ready. It is necessary to expand research on alternative energy sources and close the gaps in countries' energy needs through their consumption.

Opinion: The role of outdoor lighting with pedestrian reassurance

Opinion: The role of outdoor lighting with pedestrian reassurance

High-Performance Ionogel-Embedded electroluminescent device reliably operating in harsh environments

Recently, there have been notable strides in stretchable, adaptable displays capable of conforming to curved surfaces, including human interfaces, architecture, and vehicles. However, previous research mostly focused on coplanar structures, where the light-emitting layer is sandwiched between facing electrodes, leading to limited performance. This study introduces a breakthrough approach by embedding electrodes within the light-emitting layer and utilizing polymer electrolytes to increase lighting volume, resulting in exceptionally high brightness (3,260 cd/m2), stretchability (500 %), durability (5,000 cycles) and doubled power efficiency. Furthermore, the device with buried electrodes proves reliable even in harsh environments, such as ice or boiling water, commonly encountered in real-life scenarios. This concept paves the way for a new era of ACEL applications, including shape-adaptable outdoor lighting and displays, light-emitting soft robotics, and actuators capable of operating in challenging environmental conditions previously unattainable with other types of light-emitting devices.

Optimization of Highways and Roads Lighting

In this article is being solving а problem of cost optimization in the construction of highways and road lighting. The construction of highways over the past two or three years and planned for construction are analysed. The method for solving the issue of optimization – the development of a new luminaire, which allows to reduce capital and operating costs in the construction of outdoor road lighting. The optics of the luminaire is chosen as the main element for solving the problem. The need to optimize costs in the construction of highways is of high relevance due to the constantly growing volume of construction of outdoor road lighting.

Protective Glass in the Design of Outdoor Luminaires

In accordance with the requirements of the decree of the government (DG) of the Russian Federation, protective glass is a mandatory element of the design of utilitarian outdoor luminaries. The paper analyses the relevance of this requirement and explains the functions performed by this structural element. The protective glass of the outdoor luminaire provides significant advantages of LED outdoor lighting installations (LOLI), confirmed by analysis of the literature, calculated estimates and during experimental studies of characteristics changes during operation. Considering the identified dependencies is advisable when determining the outdoor luminaire’s maintenance and dirt depreciation factor for luminaries’ various designs.

Engineering for Whom? Investigating How Engineering Students Develop and Apply Technoskeptical Thinking

College engineering education prioritizes technical knowledge and skills, but there is growing recognition that it must also address the social and societal implications of engineering work. Beyond professional ethics, engineers need to develop broader understandings of how engineering and technology interact with and impact individuals and communities. This study focuses on the development of engineering students’ ‘technoskeptical’ ways of thinking, defined as their ability to think about technologies as more than neutral tools and analyze their complex interactions with sociotechnical systems and values. Students in the study were incoming first-year engineering students who participated in a four-week summer bridge program. The program included a course called ‘engineering design for humans and the environment,’ which foregrounded sociotechnical issues and was designed to promote technoskeptical thinking. To assess students’ uptake of technoskepticism, they completed a pre and post task on which they analyzed the unintended effects of outdoor street lighting. Although students engaged in similar technoskeptical inquiries during the design course, this study found that students tended not to transfer those emergent skills to the street lighting task. The results indicate a need to expand instructional efforts so that students more fully internalize technoskeptical practices and apply them to novel situations.

Power Scavenging Microsystem for Smart Contact Lenses.

On-the-eye microsystems such as smart contacts for vision correction, health monitoring, drug delivery, and displaying information represent a new emerging class of low-profile (≤ 1mm) wireless microsystems that conform to the curvature of the eyeball surface. The implementation of suitable low-profile power sources for eye-based microsystems on curved substrates is a major technical challenge addressed in this paper. The fabrication and characterization of a hybrid energy generation unit composed of a flexible silicon solar cell and eye-blinking activated Mg-O2 metal-air harvester capable of sustainably supplying electrical power to smart ocular devices are reported. The encapsulated photovoltaic device provides a DC output with a power density of 42.4 µW cm-2 and 2.5mW cm-2 under indoor and outdoor lighting conditions, respectively. The eye-blinking activated Mg-air harvester delivers pulsed power output with a maximum power density of 1.3mW cm-2. A power management circuit with an integrated 11 mF supercapacitor is used to convert the harvesters' pulsed voltages to DC, boost up the voltages, and continuously deliver ≈150 µW at a stable 3.3V DC output. Uniquely, in contrast to wireless power transfer, the power pack continuously generates electric power and does not require any type of external accessories for operation.

Robust hyperspectral image classification using generative adversarial networks

This paper introduces Sill-Rgan, a novel Generative Adversarial Network (GAN) designed to improve hyperspectral image (HSI) classification under varying lighting conditions. Sill-Rgan uniquely maps different light condition domains, enhancing sample classification robustness and generating new virtual samples. Addressing challenges like high spectral dimensionality and noise in HSI classification, our approach utilizes a deep proxy-based learning framework. It integrates and improves advanced GAN models and multitask networks for optimal training stability and loss function optimization. The model's mapping network is adept at generating domain-specific latent codes, enabling the transformation of original hyperspectral data into enhanced versions. Extensive experiments conducted on hyperspectral datasets of agricultural products under diverse indoor and outdoor lighting conditions confirm the effectiveness of Sill-Rgan. The results highlight the model's adaptability in both supervised and semi-supervised learning scenarios, yielding exceptional classification accuracy and enhanced data quality. The versatile potential of Sill-Rgan extends its applicability to a broad range of spectral data classifications, underlining its significant contribution to hyperspectral imaging. This advancement opens new avenues in machine vision systems, particularly in scenarios with dynamic lighting challenges.

A Robust Anti-Thermal-Quenching Phosphor Based on Zero-Dimensional Metal Halide Rb3InCl6:xSb3.

High-power phosphor-converted white light-emitting diodes (hp-WLEDs) have been widely involved in modern society as outdoor lighting sources. In these devices, due to the Joule effect, the high applied currents cause high operation temperatures (>500 K). Under these conditions, most phosphors lose their emission, an effect known as thermal quenching (TQ). Here, we introduce a zero-dimensional (0D) metal halide, Rb3InCl6:xSb3+, as a suitable anti-TQ phosphor offering robust anti-TQ behavior up to 500 K. We ascribe this behavior of the metal halide to two factors: (1) a compensation process via thermally activated energy transfer from structural defects to emissive centers and (2) an intrinsic structural rigidity of the isolated octahedra in the 0D structure. The anti-TQ phosphor-based WLEDs can stably work at a current of 2000 mA. The low synthesis cost and nontoxic composition reported here can herald a new generation of anti-TQ phosphors for hp-WLED.

Coping with darkness: residents’ experience of reduced outdoor lighting in neighbourhoods

Despite ongoing replacement of old lighting installations with new energy-efficient light emitting diodes, the energy crisis has led to the implementation of strategies for reducing energy use for public outdoor lighting in neighbourhood environments. This would save money and reduce light pollution; however, the situations should be evaluated from the residents’ perspective. This paper presents a pilot study, which aimed to explore how residents experience and respond to reduced outdoor lighting in their neighbourhoods during dark hours, by applying the adapted Human-Environment Interaction model to understand the relation between outdoor lighting quality, neighbourhood quality and local independent mobility from the residents’ perspective. The pilot study was based on a short questionnaire (N =76, 29 males, 47 females, Mage = 66.66 years) and telephone or online interviews (N = 13, 5 males, 8 females, Mage = 68.08 years) with the residents living in the neighbourhood areas, in Southern Sweden, where strategies were employed for reducing the use of public outdoor lighting. Data were collected between February and March 2023. Overall, the results affirmed the important role of outdoor lighting quality in residents’ experience of neighbourhood environments and local independent mobility (i.e. the ability of residents to walk or move around on their own in their neighbourhood area), whereas the effect of reduced outdoor lighting was rather insignificant. The interviews further showed different experiences of the reduced outdoor lighting and how the residents coped with the lighting conditions by using solutions (i.e. headlamps, flashlights, bike lamps and reflectors), and that high-level perceived safety from crime in the neighbourhoods was found to play an important role in local independent mobility during dark hours. The adapted conceptual model allowed for the evaluation of outdoor lighting conditions considering both internal and external factors from the residents’ perspective, and could provide a basis for discussion about potential changes in public outdoor lighting.

Spatial planning for dark hours in Sweden – conditions and proposal for action

The purpose of this study was to investigate how the absence of daylight are handled within spatial planning in Sweden, and to propose measures for action. The study includes a review of spatial planning documents, interviews with planning officers, and an overview of how outdoor lighting is included within the Swedish Planning and Building Act (PBL). The result shows that planning documents according to the PBL generally present few specific analyses and proposals linking to the design and the use of outdoor environments during dark hours, such as lighting. Instead, outdoor lighting is often managed within lighting masterplans, that lack a common methodology and a formal planning status. Possible consequences include that spatial planning provides limited support for how different public interests should be weighed against each other in a nocturnal context, and that citizens have little formal influence over strategic decisions on outdoor lighting. As a proposal, we suggest developing spatial planning for dark hours (‘nattstadsplanering’ in Swedish), that integrates the use, the design, and the outdoor lighting within the same planning process, using the PBL as a framework. The proposal includes clarification of lighting regulations, methodology development, and knowledge dissemination, which requires further research and investigations.