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[Display omitted] • Molecular-level light-emitting origins were strategically imparted to paper. • The morphology of AIE self-assembly can be adjusted on demand. • AFP-FP exhibited high selectivity, sensitivity and repeatable recognition of NH 3. • AFP-FP integrated with smartphone realized the visual food spoilage monitoring. Biogenic amines containing NH 3 are important indicators for conducting full-scale appraisal of food spoilage and disease diagnosis. However, the currently-used detection methods of NH 3 have several limitations such as time-consuming high cost, and inability to provide visual real-time monitoring. Therefore, researchers have attempted to explore strategies for quantitative real-time monitoring of NH 3 for food spoilage has attracted widespread attentions. Herein, we developed sustainable, fast response, hypersensitized, user-friendly and molecular-level light-emitting biomass-based materials (AFP-FP) containing on-demand nanostructured brain-cells-inspired aggregation-induced-emission (AIE) self-assembles for real-time visual monitoring of seafood spoilage. The 2-hydroxy-5-methyl-isophthalaldehyde-based AIE probe (AFP) was synthesized using a simple "one-step" route. AFP-FP exhibited high selectivity, sensitivity, repeatable and quantitative recognition (y = 7.292×103x + 7.621×104, R = 0.990) of NH 3 with a low detection limit (246 ppb) and fast response (<1 s). Furthermore, we integrated AFP-FP into a user-friendly smartphone color recognition app, enabling its practical application in visual, real-time daylight monitoring of food spoilage. [ABSTRACT FROM AUTHOR]

Shunt resistance R sh is a critical parameter for photovoltaic cells designed for low light indoor applications because it negatively affects the open circuit voltage, fill factor, and conversion efficiency. Standard CIGS cells are known to have low R sh and are, therefore, unpromising candidates for indoor energy sources. In this paper, we extend the original work of Virtuani et al. by determining the electrical specifications of many CIGS cells with copper contents [Cu]/([Ga]+[In]) as low as 0.33 and gallium contents between 0.28 and 0.81. First, IV data are fitted by a standard single-diode electrical circuit model for each illumination, resulting in light-dependent parameters. Then, we use a procedure based on a single dataset of electrical variables, i.e., independent of light, corrected by the experimental collection function, which captures light-dependent physical mechanisms. In this way, we are able to correctly reproduce the illuminance dependence of the electrical response of the PV cell over three orders of magnitude, in particular with a fixed value of the shunt resistance. The highest R sh is obtained with a low copper composition of 0.5 , regardless of the gallium composition. [ABSTRACT FROM AUTHOR]

The multiwavelength excitation (MWE) method for measuring the colorimetric properties of fluorescent whitening agent (FWA)‐treated specimens illuminated by a standard daylight illuminant computationally approximates not the spectral power distribution (SPD) of the illuminant but the luminescent SPD excited thereby by a weighted sum of the luminescent SPDs excited by a few different narrow‐band illuminations. The weights are optimized for the actual SPDs of those illuminations and the bispectral luminescent radiance factors of typical FWA‐treated paper specimens. Since the latter is invariant among instruments once provided as the common numerical data, the variations of the narrow‐band SPDs give major impacts to the reproducibility of this method. The weights optimized for the varied SPDs, however, mitigate the impacts. For investigating how they impact, one basic illumination system and its 16 simple variation systems were built virtually. The basic system consists of three narrow‐band LEDs and one blue‐excited white LED, whereas the individual simple variation system has either the peak wavelength or spectral width of one of the four LEDs (including the blue LED in the white LED) varied. With those systems, seven FWA‐treated papers with the known bispectral radiance factors were measured computationally by simulating the procedure of the MWE method. The differences in the colorimetric values measured with the simple variation systems from those with the basic system are far below the just noticeable difference, which indicates that the MWE method can be a practical solution for better reproducibility in measuring FWA‐treated papers. [ABSTRACT FROM AUTHOR]

The intensification of global warming has resulted in extremely hot weather in many parts of the world, posing a severe challenge to the health and safety of outdoor workers. Passive daytime radiative cooling (PDRC) textiles with no energy input requirements can effectively achieve temperature management. However, few wearable radiative cooling devices have been successfully prepared. This study demonstrates a radiative cooling paper (RCP) with tunable stiffness for the thermal management of human head by using SiO 2 fibers and fumed SiO 2 as emitters. The as-prepared RCP exhibits high sunlight reflectivity of 0.97, and high emissivity of 0.91 in the atmospheric window. The results demonstrate that the RCP hat can prevent hair from overheating by reducing the temperature by an average of 12.9 °C compared with a white cotton hat under peak daylight conditions. Besides, the RCP exhibits outstanding integrated properties of high mechanical properties, waterproofness, and air permeability. Therefore, it is more suitable than other textiles for the manufacture of radiative cooling hats, and offers a promising solution to solve the problem of head thermal management in outdoor conditions. [Display omitted] • This study designed and prepared a ceramic fiber paper with remarkable passive daytime radiative cooling performance. • The radiative cooling paper (RCP) exhibits good impact strength, superhydrophobicity, and air permeability. • The RCP is suitable for the manufacture of radiative cooling hat to achieve the thermal management of human head. [ABSTRACT FROM AUTHOR]

Daytime radiative cooling (DRC) has emerged as a promising method for temperature reduction of surfaces exposed to sunlight, without energy consumption. Despite advancements in DRC design, existing reflector‐based methodologies often lack transparency because of visible reflection, hindering the widespread application of this technology using glass. Efforts to address this challenge have led to the development of transparent radiative cooling (TRC), although efficient cooling during daylight remains challenging because of the dominant solar energy absorption. This paper proposes a novel TRC design comprising a polydimethylsiloxane (PDMS) emitter atop a transparent dual‐reflector structure. An optimized Bragg reflector (OBR) and a 90 µm‐hole‐punctured Ag window screen reflector (WR) are used to reflect band A of the near‐infrared (NIR) spectrum (0.74 < λ < 1.4 µm) and the overall solar spectrum, respectively. During the daytime, the proposed TRC lowers the temperature by 22.1 °C through the transparent dual reflector system, compared to a PDMS‐coated glass. Thus, this approach optimizes the balance between solar reflection and visibility using a dual reflector, offering an optimal solution for applications requiring both cooling and transparency. [ABSTRACT FROM AUTHOR]

Images captured under low-light conditions often suffer from low contrast, high noise, and uneven brightness due to nightlight, backlight, and shadow. These challenges make it difficult to use them as high-quality inputs for visual tasks. Existing low-light enhancement methods tend to increase overall image brightness, which can cause overexposure of normal-light areas after enhancement. To solve this problem, this paper proposes an Uneven Dark Vision Network (UDVN) that consists of two sub-networks. The Luminance Domain Network (LDN) uses Direction-aware Spatial Context (DSC) and Feature Enhancement Module (FEM) to segment different light regions in the image and output the luminance domain mask. Guided by this mask, the Light Enhancement Network (LEN) uses the Cross-Domain Transformation Residual block (CDTR) to adaptively illuminate different regions with various lights. We also introduce a new region loss function to constrain the LEN to better enhance the quality of different light regions. In addition, we have constructed a new low-light synthesis dataset (UDL) that is larger, more diverse, and includes uneven lighting states in the real world. Extensive experiments on several benchmark datasets demonstrate that our proposed method is highly competitive with state-of-the-art (SOTA) methods. Specifically, it outperforms other methods in light recovery and detail preservation when processing uneven low-light images. The UDL dataset is publicly available at: https://github.com/YuhangLi-li/UDVN. [ABSTRACT FROM AUTHOR]

Ambient occlusion is widely used in computer graphics to accentuate areas in a three-dimensional scene that are hidden from bright lighting. On maps, ambient occlusion adds spatial depth and nuanced texture to shaded relief images. Ambient occlusion images for maps can be calculated from digital elevation models using the Eduard relief shading application. This paper illustrates the use of ambient occlusion for cartographic terrain shading and introduces two extensions: (1) oriented ambient occlusion for modulation with a direction of illumination, and (2) reduced ambient occlusion for valley bottoms with consistent brightness. [ABSTRACT FROM AUTHOR]

This paper reviews how excessive lighting in historical sites can negatively affect the enjoyment of social gatherings. Because light pollution has the potential to affect socialization negatively, we need the appropriate tools to handle these effects. As part of this research, three techniques were used to analyze these effects: a bibliographical examination of relevant concepts, field measurements of illumination levels at historical sites in Cairo, Egypt, as well as questionnaires sent out to users around the world to determine what influences their perceptions of historical sites at night. Based on the results of a systematic review, we developed the concept of toolkits for creating a lively ambiance for evening events. Furthermore, based on the spatial measurements made in the case study, it was determined that the challenge of visual pollution hinders creating a vibrant atmosphere at historical sites. An online survey that investigated the factors influencing the enjoyment of historical sites at night around the world found that positioning the lighting fixtures and illumination is one of the most critical factors. The results of the current study confirm that the urban form of the context provides a pleasant visual and perceptual experience at night as well. The findings of this study have led to three design considerations that can help urban planners and designers when it comes to implementing lighting in public spaces. As a result of these considerations, the historical site in the case study, Al-Hussein Square, Cairo, presents a livelier ambiance at night; hence they can be used by urban designers to enhance the ambiance in similar settings to the present case study. This toolkit provides valuable insights into how local authorities and citizens can work together to reduce lighting pollution by examining the causes of the pollution. [ABSTRACT FROM AUTHOR]

Computer modeling and simulation are essential for predicting architectural solutions performance. When integrated into the design process; they are known as performance-based design. During the design process, fast analytical cycles are required. However, daylighting simulations are challenging due to computational processing and time requirements. This paper presents a comparative study of fast daylight simulation methods, two-phase, three-phase and path tracing, in a hypothetical commercial building located in Miami, Florida. Five types of static glass and one electrochromic glass were tested with six parametric models of a translucent horizontal shading device. Daysim was used as reference. The two-phase method produced results similar to the reference results with faster processing times for static facades. For dynamic facades, the path tracing method with the tested interface enabled faster simulations and parametric variations. However, the three-phase method yielded a lower average error. [ABSTRACT FROM AUTHOR]

A unidirectional Visible Light Communication (VLC) system has the potential to serve as an Indoor Positioning System (IPS). However, it is important to note that many existing VLC IPS setups rely on keeping LED lights switched on, which can lead to energy wastage when indoor lighting is unnecessary during daylight hours. Additionally, most indoor Visible Light Positioning (VLP) research has focused on 2D localization, assuming a fixed receiver height. This approach tends to overlook the positional inaccuracies that can arise due to variations in height. In this paper, to address these concerns, a 3D IPS is proposed. This system employs multiple transmitters and a single receiver, utilizing a Dark Light Visible Light Communication (DL-VLC) system. This innovative approach ensures the functionality of IPSs even when LEDs are turned "OFF" resulting in more efficient energy usage. The results of the investigation indicate that the positioning error remains within approximately 3 cm when the receiver is positioned at a height of 2.4 m, assuming standard room dimensions, which is in a fair agreement with previously published work. [ABSTRACT FROM AUTHOR]

A small framed display panel holds a selection of paper and media common in works on paper plus a set of Blue Wool Standards. The selection of materials and design of the panel including two types of glazing are presented, and the purpose of the panel as a tool for explaining the effects of light on materials is discussed. At the centre of the panel are watercolour samples prepared using primary colours in mixed washes that illustrate hue shift resulting from selective fading of one colourant. [ABSTRACT FROM AUTHOR]

Deals with a study which examined the extent of oxidation reactions on lignin after a paper was exposed to daylight. Background on the influence of light on the natural aging of paper; Materials and method; Results and discussion; Conclusions.

The present prevailing loop closure detection algorithm is mainly applicable for simultaneous localization and mapping (SLAM). Its effectiveness is contingent upon environmental conditions, which can fluctuate due to variations in lighting or the surrounding scenario. Vision-based algorithms, while adept during daylight hours, may falter in nocturnal settings. Conversely, lidar methods hinge on the sparsity of the given scenario. This paper proposes an algorithm that comprehensively utilizes lidar and image features to assign weighted factors for loop closure detection based on multi-modal sensor fusion. First, we use k -means clustering to produce a point cloud spatial global bag of words. Second, an improved deep learning method is used to train feature descriptors of images while scan context is also used to detect candidate point cloud features. After that, different feature-weighted factors are assigned for homologous feature descriptors. Finally, the detection result related to the maximum weight factor is designated to the optimal loop closure. The adaptive weighted loop closure (AWLC) algorithm we proposed inherits the advantages of different loop closure detection algorithms and hence it is accurate and robust. The AWLC method is compared with popular loop detection algorithms in different datasets. Experiments show that the AWLC can maintain the effectiveness and robustness of detection even at night or in highly dynamic complex environment. [ABSTRACT FROM AUTHOR]

Federal and state governments have recently expanded their regulatory mandates and incentives to promote renewable energy (RE) use in their planned new buildings. This requires planners to analyze and optimize their preliminary design decisions, such as building dimensions, orientation, location, and window-to-wall ratio, to maximize the use of RE in their buildings. To support designers in this critical task, this paper presents a novel model for optimizing preliminary building designs. The two optimization objectives of the optimization model focus on maximizing harvested RE and minimizing construction cost by identifying optimal building dimensions, orientation, window-to-wall ratio, and site layout. The optimization model complies with all design requirements, such as building dimensions, natural lighting, and cost-effectiveness constraints. The model performance is analyzed using two application examples to illustrate its capabilities in considering the impact of the surrounding environment on design decisions. The results of this analysis confirm the model contributions in identifying a set of nondominated optimal solutions that provide tradeoffs among the two optimization objectives of the developed model. These capabilities are expected to support building planners in identifying an optimal preliminary building design that maximizes the use of RE while minimizing all related construction costs. [ABSTRACT FROM AUTHOR]

This paper conducts a comprehensive analysis of the light environment in different areas of residential houses located in Beijing's Guangyuanli neighborhood. The main objective of this study is to assess the contribution of natural daylight to residential illuminance, with the aim of providing a foundation for reducing energy consumption and enhancing light comfort. While previous research predominantly focused on sensor deployment in single scenes such as offices and classrooms, these approaches are inadequate for multi-scene analysis of daylight in residential areas. Moreover, traditional deployment methods can negatively impact the quality of life and everyday living experience. To overcome these limitations, a prediction model is developed to estimate ceiling and window illuminance, as well as work surface illuminance in various scenes within residential buildings. The Dialux software is employed for data simulation, and a GA-optimized BP neural network is utilized to train the model, establishing the mapping relationship between input variables and corresponding illuminance outputs. By inputting sensor values from different scenarios into the model, the predicted daylight illuminance values can be obtained. This predictive approach facilitates the evaluation of light comfort and energy consumption reduction in different functional areas of residential buildings. [ABSTRACT FROM AUTHOR]

Previous studies have gained data from automated counters to compare the influence of ambient light level on the numbers of people walking and cycling. This paper reports an exploratory study using instead in-person counting, the advantage being that the apparent age and gender of each pedestrian and cyclist can also be recorded. The analysis compares travel counts in case and control periods, with case periods in daylight and darkness, to isolate the effect of change in ambient light level. As expected, the results reveal that there are fewer people walking and cycling after dark. What was unexpected was that for pedestrians, the deterrence of darkness was similar for males and females, which disagrees with previous studies capturing stated preferences suggesting that darkness is a greater deterrent for females than for males. [ABSTRACT FROM AUTHOR]

This paper addresses the issue of LED short-circuit fault detection in signaling and lighting systems in the automotive industry. The conventional diagnostic method commonly implemented in newer vehicles relies on measuring the voltage drop across different LED branches and comparing it with threshold values indicating faults caused by open circuits or LED short circuits. With this algorithm, detecting cases of a few LEDs short-circuited within a branch, particularly a single malfunctioning LED, is particularly challenging. In this work, two easily implementable algorithms are proposed to address this issue within the vehicle's control unit. One is based on a mathematical prediction model, while the other utilizes a neural network. The results obtained offer a 100% LED short-circuit fault detection rate in the majority of analyzed cases, representing a significant improvement over the conventional method, even in scenarios involving a single malfunctioning LED within a branch. Additionally, the neural network-based model can accurately predict the number of failed LEDs. [ABSTRACT FROM AUTHOR]

Traffic detection (including lane detection and traffic sign detection) is one of the key technologies to realize driving assistance system and auto drive system. However, most of the existing detection methods are designed based on single‐modal visible light data, when there are dramatic changes in lighting in the scene (such as insufficient lighting in night), it is difficult for these methods to obtain good detection results. In view of multi‐modal data can provide complementary discriminative information, based on the YoLoV5 model, this paper proposes a multi‐modal fusion YoLoV5 network, which consists of three key components: the dual stream feature extraction module, the correlation feature extraction module, and the self‐attention fusion module. Specifically, the dual stream feature extraction module is used to extract the features of each of the two modalities. Secondly, input the features learned from the dual stream feature extraction module into the correlation feature extraction module to learn the features with maximum correlation. Then, the extracted maximum correlation features are used to achieve information exchange between modalities through a self‐attention mechanism, and thus obtain fused features. Finally, the fused features are inputted into the detection layer to obtain the final detection result. Experimental results on different traffic detection tasks can demonstrate the superiority of the proposed method. [ABSTRACT FROM AUTHOR]

Alternating current can result in flickering—or pulsing—in the brightness of light emitted by luminaires. Lighting flicker typically occurs in the range of 100 to 140 cycles per second (Hz), which is too fast for visual perception by most organisms. However, evidence indicates that many organisms perceive flicker with non-visual photoreceptors present on the retinas. Exposure to flickering lights at night disrupts the circadian rhythm of organisms, leading to symptoms similar to blue light exposure at night. The traditional method for detecting flickering is with a flickermeter held near a single light. In this paper, we explore the use of high-speed camera data in the collection of temporal profiles for groups of luminaires simultaneously at distances ranging from several meters to several kilometers. Temporal profiles are extracted for individual lighting features and the full scene. The identification of luminaire types is based on their spectral signatures. With the camera data, it is possible to identify flickering and non-flickering lights, to determine the flicker frequency, to calculate percent flicker and the flicker index, and to identify groups of lights whose flickers are synchronized. Both flickering and non-flickering luminaires can be found for LED, metal halide, fluorescent, and compact fluorescent lights. To date, flickering has been detected in all of the incandescent, high-pressure sodium, and low-pressure sodium luminaires that we measured. We found that flicker synchronization is often present for lights installed within a single facility and also for strings of streetlights. We also found that flicker exposure can come from the light reflected off of the earth's surface. Luminaires designed to illuminate large areas often saturate high-speed camera data collection. This saturation can be reduced or eliminated using neutral density filters on the camera. Published experimental data on the impacts of flicker on organisms remains sparse. Many studies have drawn inferences on the impacts of spectral and lighting brightness on organisms without controlling for flicker. Our conclusion is that lighting flicker is a type of light pollution. The use of high-speed camera data makes it easier to include flicker as a variable in studies regarding the impacts of lighting on organisms. [ABSTRACT FROM AUTHOR]

The images captured by forest nighttime imaging devices are prone to degradation and noise issues due to environmental constraints. This paper proposes a novel framework based on the self‐calibrating illumination framework to improve image quality. The framework consists of four specific steps: (1) addressing non‐uniform degradation by estimating illuminance components through non‐uniform MaxRGB, (2) extracting rich information using multi‐scale inflationary convolution, (3) analyzing the relationship between different input levels and the initial level and progressively adjusting the luminance components using a channel self‐calibration module to achieve continuous improvement in luminance, and (4) designing a reflectance optimization module that enhances illuminance while suppressing noise through a regularization model. To evaluate the proposed method, a dataset comprising 1000 forest night images is constructed using an image simulation strategy. The effectiveness of this method was validated on both synthetic and real datasets, demonstrating its ability to significantly enhance nighttime forest images. When compared to six other algorithms, this method outperformed them in eight evaluation metrics, including a peak signal‐to‐noise ratio metric of 22.839 and a structural similarity metric of 0.909. The experimental results clearly indicate that this method excels in enhancing image quality and fidelity. [ABSTRACT FROM AUTHOR]

This paper describes a power-factor-corrected-based flyback converter for low-power domestic lighting. The proposed flyback converter works in a discontinuous-conduction mode (DCM) and provides enhanced power-quality (PQ). In low-power residential lighting, the flyback converter is significantly preferred over non-isolated converters owing to its numerous advantages, such as its low component count, cost-effective solution, and safe operating conditions. The proposed DCM-based flyback converter has a simple circuit configuration and lower total harmonic distortions (THD) of input current by about 15% with an input power factor of around 0.97. A hardware prototype has been developed and examined at different AC source voltages to validate the feasibility and effectiveness of a proposed model. Experimental results show that the whole system efficiency satisfies Energy Star standards with 91.04 percent efficiency at a rated load of 24 Watts and 220 V AC mains and also fulfilled the stringent limits as per IEC61000-3-2 Class D standards. [ABSTRACT FROM AUTHOR]

Underwater image restoration has been a challenging problem for decades since the advent of underwater photography. Most solutions focus on shallow water scenarios, where the scene is uniformly illuminated by the sunlight. However, the vast majority of uncharted underwater terrain is located beyond 200 meters depth where natural light is scarce and artificial illumination is needed. In such cases, light sources co-moving with the camera, dynamically change the scene appearance, which make shallow water restoration methods inadequate. In particular for multi-light source systems (composed of dozens of LEDs nowadays), calibrating each light is time-consuming, error-prone and tedious, and we observe that only the integrated illumination within the viewing volume of the camera is critical, rather than the individual light sources. The key idea of this paper is therefore to exploit the appearance changes of objects or the seafloor, when traversing the viewing frustum of the camera. Through new constraints assuming Lambertian surfaces, corresponding image pixels constrain the light field in front of the camera, and for each voxel a signal factor and a backscatter value are stored in a volumetric grid that can be used for very efficient image restoration of camera-light platforms, which facilitates consistently texturing large 3D models and maps that would otherwise be dominated by lighting and medium artifacts. To validate the effectiveness of our approach, we conducted extensive experiments on simulated and real-world datasets. The results of these experiments demonstrate the robustness of our approach in restoring the true albedo of objects, while mitigating the influence of lighting and medium effects. Furthermore, we demonstrate our approach can be readily extended to other scenarios, including in-air imaging with artificial illumination or other similar cases. [ABSTRACT FROM AUTHOR]

Lanzhou City is located in the semi-arid region of northwest China, which experiences serious desertification. Moreover, the high intensity of land development, with the accelerated industrialization and urbanization, causes increasingly aggravated conflict between humans and the environment. Exploring the response of the ecological environment quality to the natural environment and anthropogenic activities is important to protect the sustainable development of urban economic construction and the environment. Based on the Google Earth Engine (GEE) platform, this paper constructed a modified Remote Sensing Ecological Index (MRSEI) model which could reflect the ecological environment quality by integrating the desertification index (DI) into the Remote Sensing Ecological index (RSEI) model. This paper explores the spatiotemporal variation in the environmental quality from 2000 to 2020 in Lanzhou, China, and analyzes the natural and anthropogenic factors affecting the environment quality in terms of temperature, precipitation, gross domestic product (GDP), land use, night lighting, and population. The results showed that the mean value of MRSEI ranged from 0.254 to 0.400. The area undergoing fast growth in ecological quality was in the northwestern part of Lanzhou, and the area of decrease was in the central part. Various factors have different degrees of influence on the ecosystem, with temperature, precipitation, and land use having a greater impact, and GDP and population having a limited impact. Precipitation and temperature showed a strong impact when interacting with other factors, demonstrating that precipitation and temperature were also key factors affecting MRSEI. Overall, climate change and the implementation of ecological restoration projects have led to an improvement in the quality of the ecological environment in Lanzhou. This study provides a reference for understanding the spatiotemporal changes in the ecological environment in semi-arid Lanzhou and is conducive to formulating proper protection strategies. [ABSTRACT FROM AUTHOR]

In response to the pressing global challenges around climate change and the imperative of transitioning the energy market towards sustainability, this paper presents a comprehensive review starting from the late 18th century. The study examines the pivotal role of Transmission System Operators (TSOs) and Distribution System Operators (DSOs) in shaping the evolving energy landscape, with a specific emphasis on the C+++ Framework. This framework emphasizes coordination, cooperation, and collaboration between TSOs and DSOs to achieve sustainable energy systems through the integration of renewable energy technologies, storage systems, and efficient energy demand management. In addition, the review provides a historical overview of global warming from 1800 to the present, highlighting key events and developments related to greenhouse gas emissions. Furthermore, the paper delves into the significance of international agreements such as the Paris Agreement and the importance of reducing greenhouse gas emissions for a sustainable future. Recognizing the vital role of the C+++ Framework, the paper concludes with a discussion of future hybrid sustainable technologies incorporating various storage and efficient lighting technologies that can optimize energy management and reduce carbon emissions. This research aims to contribute valuable insights to inform energy policy and decision-making processes for a reliable, efficient, and sustainable energy delivery system. [ABSTRACT FROM AUTHOR]

The structural collapse of a street lighting pole represents an aspect that is often underestimated and unpredictable, but of relevant importance for the safety of people and things. These events are complex to evaluate since several sources of damage are involved. In addition, traditional inspection methods are ineffective, do not correctly quantify the residual life of poles, and are inefficient, requiring enormous costs associated with the vastness of elements to be investigated. An advantageous alternative is to adopt a distributed type of Structural Health Monitoring (SHM) technique based on the Internet of Things (IoT). This paper proposes the design of a low-cost system, which is also easy to integrate in current infrastructures, for monitoring the structural behavior of street lighting poles in Smart Cities. At the same time, this device collects previous structural information and offers some secondary functionalities related to its application, such as meteorological information. Furthermore, this paper intends to lay the foundations for the development of a method that is able to avoid the collapse of the poles. Specifically, the implementation phase is described in the aspects concerning low-cost devices and sensors for data acquisition and transmission and the strategies of information technologies (ITs), such as Cloud/Edge approaches, for storing, processing and presenting the achieved measurements. Finally, an experimental evaluation of the metrological performance of the sensing features of this system is reported. The main results highlight that the employment of low-cost equipment and open-source software has a double implication. On one hand, they entail advantages such as limited costs and flexibility to accommodate the specific necessities of the interested user. On the other hand, the used sensors require an indispensable metrological evaluation of their performance due to encountered issues relating to calibration, reliability and uncertainty. [ABSTRACT FROM AUTHOR]

This paper examines the material damage caused to the owner of the property as a result of the violation of the design rules. This phenomenon was observed by the authors participating in the period 2018-2021 in the assessment of over 500 construction projects of residential blocks on the territory of the Republic of Moldova. In about 50% was found a violation of lighting regulations. Through this study, we aimed to investigate the ways to assess the extent of the damage caused by the reduction of the level of daylight lighting in residential buildings in the specific conditions of the real estate market in the Republic of Moldova. This paper aims to: Identify the legislative and normative framework that regulates the process of ascertaining the damage caused to the owner of the residential real estate following the reduction of the level of sunshine and natural lighting; Determine the consequences of reducing the level of sunshine and natural lighting for residential buildings; Propose methods for estimating the material damage caused to the owner of the damaged real estate under the conditions of the Republic of Moldova. [ABSTRACT FROM AUTHOR]

Micro-LED arrays exhibit high brightness, a long lifespan, low power consumption, and a fast response speed. In this paper, we have proposed a series-biased micro-LED array by using a nitride layer with multi-quantum wells epitaxial on sapphire substrate. The III-nitride multiple quantum wells serving as the micro-LED active material enable both luminescence and detection functionalities. The micro-LED array combines lighting, detection, and communication capabilities. We have conducted a thorough analysis of the micro-LED array's optoelectronic features in both lighting and detection modes. We also explore visible light communication performance across different arrangements of single micro-LED devices within the series-biased array. Our research achieves 720p video transmission via visible light communication using the micro-LED array, supporting a communication rate of up to 10 Mbps. Our contributions encompass the successful integration of lighting and detection functions and a comprehensive assessment of optoelectronic and communication performance. This study highlights the multifunctional micro-LED array's potential as a transceiver terminal in visible light communication systems, expanding its applications from smart lighting to visible light communication and photonic integrated chips. These innovations enhance our understanding of micro-LED technology and its versatile applications. [ABSTRACT FROM AUTHOR]

This paper introduces a comprehensive methodology for creating diverse layout generation configurations, aiming to address limitations in existing building optimization studies that rely on simplistic hypothetical buildings. This study's objective was to achieve an optimal balance between minimizing the energy use intensity (EUI) in kWh/m2, maximizing the views percentages to the outdoor (VPO), achieving spatial daylight autonomy (sDA), and minimizing annual sunlight exposure (ASE). To ensure the accuracy and reliability of the simulation, the research included calibration and validation processes using the Ladybug and Honeybee plugins, integrated into the Grasshopper platform. These processes involved comparing the model's performance against an existing real-world case. Through more than 1500 iterations, the study extracted three multi-regression equations that enabled the calculation of EUI in kWh/m2. These equations demonstrated the significant influence of the window-to-wall ratio (WWR) and space proportions (SP) on the EUI. By utilizing these multi-regression equations, we were able to fine-tune the design process, pinpoint the optimal configurations, and make informed decisions to minimize energy consumption and enhance the sustainability of residential buildings in hot arid climates. The findings indicated that 61% of the variability in energy consumption can be attributed to changes in the WWR, as highlighted in the first equation. Meanwhile, the second equation suggested that around 27% of the variability in energy consumption can be explained by alterations in space proportions, indicating a moderate correlation. Lastly, the third equation indicated that approximately 89% of the variability in energy consumption was associated with changes in the SP and WWR, pointing to a strong correlation between SP, WWR, and energy consumption. The proposed method is flexible to include new objectives and variables in future applications. [ABSTRACT FROM AUTHOR]

Appropriate daylight control could maximize occupants' visual comfort, potentially saving energy. However, the deployment of daylight control systems (DLCSs) is not happening, mainly due to the complex system calibration and the frequent reluctance of occupants toward automatic control systems that exclude their participation. In this paper, a human-in-the-loop DLCS is presented. The system is designed to allow the users to have direct interaction via smartphone Bluetooth communication, enabling them to set the lighting values deemed most comfortable nimbly. Special attention has been paid to the power consumption of the DLCS, especially in standby mode. Accessibility of configuration has been taken into consideration, leading to the choice of a wireless configured device. The performance of the prototype DLCS was evaluated experimentally in a side-lit room and compared with that of a commercial controller. The illuminance on a reference work plane was measured during the operation of the systems to observe the controllers' effect on the lamp's luminous flux while simultaneously considering the variation of daylight conditions. Moreover, the energy performance of the systems was studied to obtain information about the energetic effectiveness and convenience of the studied DLCSs. The main results showed that the proposed system could maintain the required target illuminance values on the work plane as daylight conditions vary: the maximum deviation measured using the prototype never exceeded 11 lx. In comparison, the commercial controller reached peaks of 220 lx. Moreover, the energy consumption of the prototype (resulting equal to 370 mVA) was lower than the consumption of the commercial system (equal to 600 mVA), allowing for increased energy savings over the long period. The more straightforward configuration allows the user to better interact with the DLCS. [ABSTRACT FROM AUTHOR]

Phosphor conversion materials with excellent thermal stability and broad-spectrum is critical to obtaining laser lighting devices with high luminous flux and CRI. In this paper, high thermally stable green AlN-Lu 3 Al 5 O 12 :Ce (ASL) and red AlN–CaAlSiN 3 :Eu (ASR) composite phosphor ceramics were prepared by embedding phosphor into AlN ceramic matrix. With mass ratio of phosphor increasing, luminescence intensity and quantum efficiency gradually increased, and the maximum internal quantum efficiency reached 62.8 % and 78.9 % for ASL and ASR, respectively. Under laser exciting in reflection mode, ASL-20 and ASR-50 got the max luminous emittance of 2827.5 lm/mm2 and 268.7 lm/mm2 with a saturation laser power density of 60.4 W/mm2 and 16.7 W/mm2, respectively. The diffusion coefficient of Ca, Al, Si between AlN and CASN grains was 2–4 magnitude higher than that of Lu, O, N between AlN and LuAG grains, confirming facile solid solubility of AlN and CASN. Finally, luminescence performances of green-red color wheel fabricated by ASL and ASR were evaluated. When the area ratio of green to red was 2:1, the color wheel yielded the biggest CRI of 82.6. This work presents a facile strategy for fabricating high thermally stable AlN-based composite phosphor ceramic and its application in high-quality laser lighting and display devices. [ABSTRACT FROM AUTHOR]

Artificial lighting is a necessity in the conduct of activities, especially at night. The use of fluorescent and LED lighting sources has led to a decrease in electricity consumption compared to incandescent lighting sources. The paper presents a case study highlighting the voltage and current waveforms in the operation of the analyzed sources. A considerable distortion of the current waveform is found, identifying the need for measures to improve power quality. The photometric measurements showed that for some light sources the luminous flux on the box is higher than the luminous flux actually emitted. [ABSTRACT FROM AUTHOR]

Natural light continuously changes its correlated color temperature (CCT) from sunrise to sunset, providing the best color reproducibility and healthy light. In the lighting field, efforts have been made to improve the Color Rendering Index (CRI) to provide light quality at the same level as natural light. A unique light source technology that mixes and controls multiple LED light sources with different spectral or CCT characteristics or provides a high color rendering index has been introduced. However, the characteristics of natural light, which provide high CRI light while changing color temperature every moment, could not be reproduced as they were. Therefore, in this paper, we propose a CRI-based smart lighting system that reproduces natural light characteristics, provides light with high color reproducibility, and maintains homeostasis even under the changing environment of natural light CCT. After extracting the CCT for each day from the characteristics of measured natural light, the light with the highest CRI under the CCT condition for each hour was provided through a CRI-based CCT matching algorithm. Performance evaluation was conducted for four-channel LED experimental lighting. For each clear and cloudy day, daily natural light was reproduced with a light quality higher than average CRI 98 within the MAE range of CCT 6.78 K. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to investigate the impact of circadian lighting-induced melatonin suppression on patients with psychiatric and neurological disorders in hospital wards by using an ad-hoc metrology framework and the subsequent metrics formalized by the CIE in 2018. A measurement scheme was conducted in hospital ward rooms in the Department of Neurology, Zealand University Hospital, at Roskilde in Denmark, to evaluate the photometric and colorimetric characteristics of the lighting system, as well as its influence on the circadian rhythm of the occupants. The measurement scheme included point measurements and data logging, using a spectrophotometer mounted on a tripod with adjustable height to assess the newly installed circadian lighting system. The measured spectra were uploaded to the Luox platform to calculate illuminance, CCT, MEDI, etc., in accordance with the CIE S026 standard. Furthermore, the MLIT based on MEDI data logging results was calculated. In addition to CIE S026, we have investigated the usefulness of melatonin suppression models for the assessment of circadian performance regarding measured light. From the results, the lighting conditions in the patient room for both minimal and abundant daylight access were evaluated and compared; we found that access to daylight is essential for both illumination and circadian entrainment. It can be concluded that the measurement scheme, together with the use of the Luox platform and Canva template, is suitable for the accurate and satisfactory measurement of integrative lighting that aligns with CIE requirements and recommendations. [ABSTRACT FROM AUTHOR]

Undoubtedly, light is a key element for human beings to adapt to their environment and to see the form, the color, and the perspectives of different objects in their immediate surroundings. Almost 80 percent of the information we obtain daily through our senses we obtain through sight. The correct design of the illumination system and building facades should offer optimal conditions for visual comfort. To achieve this aim, a collaboration between architects, lighting designers, and engineers should be established to improve citizens’ quality of life. This paper sought to bridge this knowledge by finding the link between daylighting, the building façades, and visual comfort. Accordingly, the paper conducts a theoretical review to evaluate the existing studies in an attempt to present this linkage focusing on kinetic façades. Then, an analytical review is conducted for 38 eligible records, that are extracted from different scholarly databases to find the assessment methods and tools used to determine the most favorable conditions of daylight for intelligent facades. Ultimately, the outcomes of the research will provide insights for further studies, in addition to that these connections can inform policy development to assist architects to design effective facades and more adaptive capabilities designed for the building envelope. Kinetic facades were found to provide visual comfort in addition to various productivity, economic, and environmental benefits, which in turn enhance the quality of life. [ABSTRACT FROM AUTHOR]

From the beginning of the 21 st century until today, the demand for lighting systems includes not only visual parameters (brightness, contrast perception, color quality), but also non-visual parameters. It is necessary to define the new non-visual parameters for the realization of the new concept of Human Centric Lighting (HCL) or Integrative Lighting. As a contribution to this approach, many international research groups have tried to quantify the non-visual parameters such as Circadian Stimulus by Rea et. al. in USA ( C S 2018 , C S 2021 ), Melanopic Equivalent Daylight ( D 65 ) illuminance, mEDI of the CIE S 026/E:2018 or the latest formula by Giménez et al., for the nocturnal melatonin suppression. Therefore, it is necessary to analyze the correlation between these non-visual metrics and brightness metrics such as the equivalent luminance of Fotios et al., or the latest brightness model of TU Darmstadt so that scientists, lighting engineers and lighting system users can correctly apply them in their work. In this context, this paper attempts to investigate and analyze these correlations between the three metric groups based on the database of 884 light sources of different light source technologies and daylight spectra. The obtained results show that the latest Circadian Stimulus model of Rea et. al. C S 2021 with the improvement of Circadian Light C L A , 2021 ( C L A 2.0 ) has solved the disadvantage of C S 2018 , especially for the interrupted point between warm and cold white (about 3710 K ) or the junction between negative and positive signal of the opponent channel ( B - (L + M) ). Moreover, these three metrics of the three research groups contain a high correlation coefficient, so that one metric can be transformed by linear functions to the other two parameters. [ABSTRACT FROM AUTHOR]

Good design strategies can help reduce energy consumption and ensure proper natural lighting. In the process of building design, this paper uses orthogonal analysis to identify design elements that correspond optimally to light levels. The visible light transmission ratio, horizontal sunshade baffle depth, sunshade angle, horizontal sunshade height from the window, and heat transfer coefficient were selected as influencing factors. The design elements corresponding to the lowest energy consumption were found. The test points are representative, and the number of tests is small. [ABSTRACT FROM AUTHOR]

Images captured in bad weather conditions such as fog, mist, haze, etc., are severely degraded due to the scattering of the particles in the atmosphere. These images are inappropriate for various applications of computer vision, e.g., transportation, remote sensing, video surveillance object recognition, etc. Image dehazing is the process of removing the haze effect from an image so that these applications can be benefited. The physical model of haze formation is used to restore a hazy image which requires two parameters to estimate: transmission and airlight. The accuracy of the dehazing depends on the estimation of the transmission. Dark channel prior (DCP) is an effective method to compute the transmission. However, a dark channel underestimates the transmission when an object in the scene has a similar color to the atmospheric light or sky region, as a result, the dehazed image looks dark. In this paper, we explore the DCP from a new perspective and reformulate it into contrast, saturation and brightness. We proposed a method to estimate the transmission without computing the dark channel. To overcome the problem of over-enhancement and remove the haze effect, a nonlinear model based on inverse strategy is introduced. It prevents the transmission from becoming over-estimated or under-estimated. The experimental result section demonstrates the efficacy of the proposed method over the natural and synthetic hazy images along with qualitative and quantitative analysis. [ABSTRACT FROM AUTHOR]

Light pollution has a detrimental effect on astronomy. Artificial light emitted from outdoor lighting increases the brightness of the night sky, making it difficult to observe astronomical objects. The spectral power distribution of artificial light sources is one of the key factors determining how much the night sky is deteriorated by light pollution. The ongoing replacement of discharge lamps with LED sources may have a major impact on astronomy because LED spectra usually cover the entire visible radiation range. This paper provides an analysis of the impact of LED sources with correlated color temperature in the range from 1000 K to approximately 10 000 K on visual and instrumental astronomical observations. For each analyzed artificial source, the Starlight Contamination Degree (SCD) index, i.e. a quantity that allows for quick evaluation of the impact of the sources on the night sky, is calculated. The reflection of artificial light from different ground surfaces and its scattering in the atmosphere was included in the calculation of the SCD index. LED lamps with very low values of correlated color temperature (CCT) and color rendering index (CRI) were found to possibly have a similar or even smaller impact on astronomical observations than sodium discharge lamps. Moreover, professional astronomical observations are more affected by LED lamps than visual observations, even for lamps with the lowest CCT and CRI. Thus, additional measures (e.g. reducing lumen output) should be applied to protect observational conditions. The results of the study help to assess which LED lamps can be used, and which should be avoided in the protection zones around astronomical observing sites. [ABSTRACT FROM AUTHOR]