LED Panel Research Articles

A multi-objective natural aggregation algorithm for optimizing user allocation matrix in visible light communication

Allocating users to LED panels in a visible light communication (VLC) environment is a non-convex multi-objective constrained optimization problem. The computational complexity and accuracy of the optimization are the key factors to deal with in a VLC environment. In this manuscript, initially the user allocation problem is formulated as a single objective optimization problem by using sum-utility function of data rate and blockage probability. Then these two contradictory objective functions are simultaneously optimized by a new multi-objective natural aggregation algorithm (MONAA). This proposed algorithm is inspired by the aggregation behavior of cockroaches which help them to determine the darkest spot in a search space. The performance of this multi-objective algorithm is compared with NSGA-II, MOPSO, MOEA/D and MOSOS on eight unconstrained and six constrained mathematical function optimizations. In single objective and multi-objective cases, superior performance is demonstrated by the natural aggregation algorithm for solving the user allocation matrix optimization.

Recycling of Zinc-Carbon Batteries into MnO/ZnO/C to Fabricate Sustainable Cathodes for Rechargeable Zinc-Ion Batteries.

Acidic zinc-carbon dry batteries have been widely used in life because of their low cost. However, a great quantity of used batteries is discarded as refuse, which not only wastes resources but also leads to environmental contamination. To reuse spent batteries on a large scale, this study concerns a simple, effective, and sustainable strategy to turn them into MnO/ZnO/C composites. After a conventional leaching treatment followed by pyrolysis, the rust cathode materials can be reduced to MnO/ZnO/C. When serving as a rechargeable zinc-ion battery cathode, this electrode provides a maximum reversible capacity of around 362 mAh g-1 MnO ) and a rate capability of 191 mAh g-1 MnO at a high current rate of 1.20 A g-1 . Furthermore, ZnO gradually dissolves in the electrolyte with the increase of discharge cycles, replenishing the Zn2+ content in the electrolyte and further enhancing cycling stability (98.02 % after 500 cycles). The device also exhibits a remarkable energy density of 336.37 Wh kg-1 , low self-discharge rate, and can efficiently power a LED panel. This strategy offers an economical and facile route to convert zinc-carbon battery waste into useful materials for aqueous rechargeable zinc ion batteries.

0015 Effectiveness-Implementation Study of Two Novel Lighting Interventions for Shiftworkers on a Submarine Watchfloor

Abstract Introduction Shiftwork is common in the military, where around-the-clock readiness is necessary. Yet, non-standard schedules can negatively impact sleep, circadian health, and performance. Light is a leading countermeasure due to its phase shifting and alerting properties, with higher intensities and shorter wavelengths eliciting relatively greater effects. New technologies allow for deliberate spectral engineering that targets specific photobiological responses. This study examined the efficacy and implementation of two spectrally-distinct lights for improving sleep, alertness, and performance in active duty service members working nightshift schedules. Methods Participants were service members working 12-h shifts (0530-1730) on a high-security, submarine watchfloor (N=56, 9 females; mean+SE age=28.95 + 0.76). Lighting interventions included LED panels (3,721 cm2) that were either enhanced (SW+) or depleted (SW-) in short wavelength energy, while maintaining a comparable color temperature (~3000 K) and photopic illumination (~300 lux at 46 cm from eyes). For both SW+ and SW-, a bank of light panels were arranged across the front of the watchfloor and illuminated for the full duration of the nightshift. In addition, participants wore blueblocker glasses after nightshifts up until bedtime, when eye masks were worn during sleep. There were two data collection periods that coincided with existing 16-day schedule cycles: the first contained an 8-day baseline (BL1) and 8-day SW+ condition, and the second contained an 8-day baseline (BL2) and 8-day SW- condition (order within those 16-day periods was pseudo-randomized). Sleep and alertness were assessed via actigraphy, sleep diary, psychomotor vigilance test (PVT), and Karolinska Sleepiness Scale (KSS). Implementation metrics were obtained with questionnaires. Results All analyses are still ongoing. Preliminary examinations show higher satisfaction with the SW+ than BL1, and greater comfort and fewer symptoms under both SW+ and SW- as compared to BL1. Most felt the SW+ and SW- improved alertness on shift and expressed an interest in keeping the lights on the watchfloor. Conclusion Findings thus far indicate the interventions were well-received by participants. Subsequent analyses will further examine barriers to intervention use and the efficacy of the lights for improving sleep, alertness, and performance in service members working nightshifts. Support (If Any) ONR TS-788

Environmental and social life cycle assessments of an industrial LED lighting product

It is necessary to assess a product's sustainability from both environmental and social perspectives. However, combined environmental and social performance assessments have not been given enough attention. This paper presents a combined Environmental Life Cycle Assessment (E-LCA) and Social Life Cycle Assessment (S-LCA) of an industrial LED luminaire through its life cycle. The LCA screening studies were conducted in line with ISO 14044 and United Nations Guidelines for E-LCA and S-LCA with Ecoinvent and PSILCA databases. The study analysed the key potential risks as well as the interrelation between E-LCA and S-LCA results, in which the production of LED driver, LED panel, and electricity consumption were identified as the hotspot processes to both environmental and social impacts. Four social issues were identified, namely ‘association and bargaining rights’, ‘sanitation coverage’, ‘public sector corruption’ and ‘pollution’. LED driver and panels are responsible for 78% and 20% of the environmental impacts respectively in the production phase. Electricity accounts for an average of 51% of environmental impacts. The process also made the key contribution to the ‘social responsibility along the supply chain’ (52%), ‘industrial water depletion’ (84%) and ‘contribution to environmental load’ (63%) risks. Meanwhile, in the category ‘contribution to economic development’, 18% positive social impacts were identified. Based on the results obtained, recommendations were derived for the development of sustainable LED lighting products and services with a trade-off between the environmental impact and the socio-economic benefits. According to the literature review, this research is the first attempt to assess a combined environmental and social performance in industrial LED lighting products and provides a valuable contribution to knowledge for future research in this area.

A Device for Visualizing Wi‐Fi Frames Using an LED Panel

In this letter, we propose a device that visualizes Wi‐Fi frames in a wireless LAN for beginners with little knowledge of networks. Our visualization device focuses on the nearest Wi‐Fi device and uses a blinking LED panel to convey the frames that are transmitted and received by that device. The blinking pattern and the color of the LED panel depend on the difference in the frame type between transmission and reception, thus allowing a user to intuitively understand what kind of frames are being sent and received. We implemented our proposed device using commercially available products and confirmed that it performs as expected. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

Video analytics-based real-time intelligent crossing detection system (RICDS): Killer app for edge computing

In this paper, we design and implement a video analytics based real-time intelligent crossing detection system (RICDS) as a novel safety service for the smart city. This system spans across the edge device and visualization unit, with reduced latency. To enhance object tracking in the proposed RICDS on the edge devices, which has limited computational resources, we first design an adaptive queue management-based object tracking (QMOT) scheme. This scheme adaptively controls the maximum queue size to meet the target delay requirement for the RICDS while the image frames come into the proposed queue to wait for object detection and tracking. In this sense, the maximum queue size is calculated by the target delay requirement and weighted-average of processing time, so that some redundant frames for object detection are automatically dropped due to the overflow of the maximum queue size. Moreover, we introduce the real-world-real-time (RR) tracking scheme that lightly tracks multiple objects (i.e., pedestrians in this scenario) by predicting the future position of the object and assigning unique IDs to them. Specifically, to predict the future positions of multiple objects in a lightweight manner, the possible movement boundary of every single object is determined by considering both the movement directions and movement speeds of each object to reduce search space for mapping IDs to the objects. Here, the movement directions and movement speeds are also calculated based on the real-world coordinate system after calibrating of image frame’s coordinate system into the real-world one. Finally, we implement the proposed RICDS on various commercial edge devices and a visualization unit (i.e., the LED panel). Moreover, the GUI application at the remote server is provided for (i) monitoring the result of the detection and tracking and (ii) dynamically changing the configuration settings. The measurement-based experiments show that the proposed tracking scheme achieves a latency reduction of about 33%–62% compared to the benchmark schemes on the NVIDIA Xavier while exhibiting similar multi object tracking accuracy performance compared to the benchmark schemes.

Modeling and Optimizing the Effect of Light Color, Sodium Chloride and Glucose Concentration on Biomass Production and the Quality of Arthrospira platensis Using Response Surface Methodology (RSM).

Arthrospira platensis (Spirulina) biomass is a valuable source of sustainable proteins, and the basis for new food and feed products. State-of-the-art production of Spirulina biomass in open pond systems only allows limited control of essential process parameters, such as light color, salinity control, or mixotrophic growth, due to the high risk of contaminations. Closed photobioreactors offer a highly controllable system to optimize all process parameters affecting Spirulina biomass production (quantity) and biomass composition (quality). However, a comprehensive analysis of the impact of light color, salinity effects, and mixotrophic growth modes of Spirulina biomass production has not been performed yet. In this study, Response Surface Methodology (RSM) was employed to develop statistical models, and define optimal mixotrophic process conditions yielding maximum quantitative biomass productivity and high-quality biomass composition related to cellular protein and phycocyanin content. The individual and interaction effects of 0, 5, 15, and 30 g/L of sodium chloride (S), and 0, 1.5, 2, and 2.5 g/L of glucose (G) in three costume-made LED panels (L) where the dominant color was white (W), red (R), and yellow (Y) were investigated in a full factorial design. Spirulina was cultivated in 200 mL cell culture flasks in different treatments, and data were collected at the end of the log growth phase. The lack-of-fit test showed that the cubic model was the most suitable to predict the biomass concentration and protein content, and the two-factor interaction (2FI) was preferred to predict the cellular phycocyanin content (p > 0.05). The reduced models were produced by excluding insignificant terms (p > 0.05). The experimental validation of the RSM optimization showed that the highest biomass concentration (1.09, 1.08, and 0.85 g/L), with improved phycocyanin content of 82.27, 59.47, 107 mg/g, and protein content of 46.18, 39.76, 53.16%, was obtained under the process parameter configuration WL4.28S2.5G, RL10.63S1.33G, and YL1.00S0.88G, respectively.

A Sprayable and Visible Light Rapid-Cured Strippable Film for Surface Radioactive Decontamination.

Strippable film is effective for removing radioactive contamination. However, it still has some limitations, such as the long curing time (about 30 min~24 h) and the requirement of organic solvents. To address these issues, we report a simple protocol to prepare strippable decontamination films using liquid polybutadiene (LPB) and tert-butyl acrylate (TBA) as the raw materials without solvent and using camphorquinone/ethyl 4-dimethylaminobenzoate (CQ/EDB) as a photoinitiator, where the film was formed under household LED panel light or daylight irradiation for about 540 s. After a thorough study of viscosity, real-time Fourier transform infrared (RT-FTIR spectra), gel and volatile organic compound (VOC) contents, mechanical properties and decontamination efficiency, the optimum composition and curing conditions were determined for the decontamination strippable film. VOC content is as low as 12.7 ± 0.7% and the resultant strippable film exhibits good mechanical performances with a tensile strength of up to 5.4 ± 0.4 MPa and elongation of up to 66.6 ± 13%. Most important, the decontamination efficiencies of this strippable film for 133CsCl on glass, ceramic and metal surfaces reach up to 98.1%, 94.3% and 97.6%, respectively.

A system dynamics approach to measure the effect of information sharing on manufacturing/remanufacturing systems’ performance

ABSTRACT Nowadays, the necessity to measure, control, and improve manufacturing systems’ economic and environmental performances is becoming vital to achieve competitive advantages. To deal with these challenges, closed-loop supply chain networks are a very useful concept to reduce the manufacturing systems’ total cost and environmental impacts. Hence, in this work, particular focus is given to the closed-loop supply chain management to reduce, reuse, remanufacture, and recycle the used products. In this regard, in this study, the authors propose a closed-loop supply chain model, including a manufacturer and a retailer. Decision and policymaking in such a real supply network is very complex. As a result, a system dynamics model has been developed to provide a computer-integrated network, measure, control, and improve the impact of parameters’ variation, such as information sharing, on the electronics product manufacturing system’s performance bullwhip effect sensitivity analysis. The results show that the appropriate policy and electronic recovery effectively can reduce the bullwhip effects, increase economic performance, and reduce the proposed closed-loop supply chain components’ order preparation time and return rate. Finally, the paper uses an LED panel manufacturer’s case to validate the application of the methodology and verify the results.

3 Boyutlu Özgün Tasarımı ile Çok Renkli LED Tabanlı Fototerapi Cihazı Üretimi

Jaundice is a condition that results from an increase in bilirubin level in the blood. Its prevalence in newborns is around 60-70%. When this temporary jaundice becomes pathological and left untreated, significant damages may occur such as brain damage, vision loss, lung and kidney dysfunction, and even death. One of the methods used for the treatment of jaundice is phototherapy. In this study, a design has been made with 3 foldable LED panels to increase the target area. In addition, high-voltage LEDs with blue-green white wavelengths were used. Thus, it was aimed to minimize the risks of nausea and dizziness caused by intense blue light. An automatic system has been achieved by using temperature and light intensity sensors. The system will warn the user at temperatures and light intensity that are harmful to the baby.

Humic acids impact on heavy metal phytoextraction in Tagetes patula L.

In a model study, we analysed the impact of humic acids (HAs, 500 ppm) on the accumulation of heavy metals (HMs; Pb, Cu, Ni and Zn) in roots and aboveground organs of the annual ornamental plant Tagetes patula (Scarlet variety) cultivated on the Terra Vita nutritive substrate used in modern cultural landscape mulching to imitate the upper fertile root layer (UR-RAT) of contaminated urban soils in megacities. Plants were grown in full photoculture (at no sunlight) in pots placed in a closed grow box, maintaining internal microclimate. A modern HLG Quantum Board QB288 V2 Rspec LED panel enabled with vegetation modes was used as light source. HMs were introduced in substrate as aqueous saline. Each setting was quadruplicated. Total experiment duration was 30 days. Tagetes patula was proved a particularly effective phytoextractor of Zn applied at 40 mg/kg (p<0.01). At the same time, the plants showed high tolerance to toxic growth inhibition (in biometry of the above- and underground organ length and mass) and preserved external aesthetics. Metals were further graded by phytomass accumulation as follows: Cu>Pb>Ni. Ni at 30 mg/kg had a major impact on plant weight and length, which sets off the variety as a sensitive phytoexcluder for this metal. HAs increased aboveground mass in all settings and decreased the HM mass impact. A sharp root mass reduction was observed in combinations of the two factors (HMs+HAs), which was clearly reflected in impaired root mass in zinc settings. A single metal addition reduced the mass by average 12.0 % (p<0.01) vs. control (no HAs or HMs), whilst a combined HAs+HMs administration induced its 65.0 % reduction (p<0.01). The results obtained indicate a good root buffering capacity for HM translocation from the rhizosphere to aboveground parts. In general, HA usage is promising for creating the green space and phytoremediation of urban HM-contaminated soils.

Multi-pulse triboelectric nanogenerator based on micro-gap corona discharge for enhancement of output performance

Triboelectric nanogenerator (TENG), which can convert all forms of mechanical energy into electricity, has been hailed as one of the economical ways to harvest energy. However, the development and application of TENG are limited due to its low output power. Although it is found that the power of TENG can be increased by introducing corona discharge, there are few studies on the influential factors of TENG based on corona discharge. In this paper, the multi-pulse triboelectric nanogenerator (MP-TENG) with enhanced output power is proposed by controlling the negative corona discharge through the integration of TENG and the micro-gap. The experimental results show that Voc, Isc and Qsc are improved 154%, 725% and 3025% respectively. Moreover, the highest power growth rate of 646% can be achieved under a low frequency. The MP-TENG demonstrates a superior output performance that the charging time of 100 μF capacitor to 3.5 V shortens by 1/5 and 12 parallel LED panels (240 lamp beads) can be lit up, which presents a great potential in practical application and plays a guide role in introducing corona discharge into the TENG.

The Effect of Bright Light Treatment on Rest-Activity Rhythms in People with Dementia: A 24-Week Cluster Randomized Controlled Trial.

Bright light treatment is an effective way to influence circadian rhythms in healthy adults, but previous research with dementia patients has yielded mixed results. The present study presents a primary outcome of the DEM.LIGHT trial, a 24-week randomized controlled trial conducted at nursing homes in Bergen, Norway, investigating the effects of a bright light intervention. The intervention consisted of ceiling-mounted LED panels providing varying illuminance and correlated color temperature throughout the day, with a peak of 1000 lx, 6000 K between 10 a.m. and 3 p.m. Activity was recorded using actigraphs at baseline and after 8, 16, and 24 weeks. Non-parametric indicators and extended cosine models were used to investigate rest–activity rhythms, and outcomes were analyzed with multi-level regression models. Sixty-one patients with severe dementia (median MMSE = 4) were included. After 16 weeks, the acrophase was advanced from baseline in the intervention group compared to the control group (B = −1.02, 95%; CI = −2.00, −0.05). There was no significant difference between the groups on any other rest–activity measures. When comparing parametric and non-parametric indicators of rest–activity rhythms, 25 out of 35 comparisons were significantly correlated. The present results indicate that ambient bright light treatment did not improve rest–activity rhythms for people with dementia.

EVALUATION OF ECONOMIC EFFICIENCY OF MODERNIZATION OF ARTIFICIAL LIGHTING OF EDUCATIONAL INSTITUTIO

The analysis of technical characteristics and cost of modern light sources and motion sensors used in administrative premises is carried out. It has been established that lighting of corridor-type rooms using LED panels of the lower and middle price ranges with a luminous efficiency of 80-85 and 100 lm/W, accordingly, becomes less expensive in the second year of operation compared to fluorescent lighting. Installation of panels with a higher luminous efficiency, up to 120 lm/W, at the current level of prices on them has certain risks, as the payback period of the investment in this case is about 7 years, exceeding the warranty period of these panels. The payback period of investment in the automation of lighting control in corridor-type rooms using relatively inexpensive infrared motion sensors and the expected reduction of energy consumption by 30% does not exceed 5 years, demonstrating the feasibility of this event. Measures for replacing fluorescent lamps with LED panels in less loaded classrooms, up to 510 hours of operation per year, have a payback time of 4-6 years, which exceeds the warranty period of the panels. Therefore, according to the authors of the article, it is appropriate to first replace the lamps in the corridors, and then, after accumulating experience in operating the purchased light sources, to replace them in the classrooms. Due to their high cost in the premises of educational institutions, the use of presence sensors as well as automated lighting level control systems is not economically feasible. The urgency of saving energy by replacing fluorescent lamps with LED and automation of lighting control, due to the trend towards an increase in the cost of electricity, will also grow. The algorithms and formulas given in the article for determining the present value, payback periods are simple and can be applied to other types of light sources and design conditions.

Light-Induced GFP Expression in Zebrafish Embryos using the Optogenetic TAEL/C120 System.

Inducible gene expression systems are an invaluable tool for studying biological processes. Optogenetic expression systems can provide precise control over gene expression timing, location, and amplitude using light as the inducing agent. In this protocol, an optogenetic expression system is used to achieve light-inducible gene expression in zebrafish embryos. This system relies on an engineered transcription factor called TAEL based on a naturally occurring light-activated transcription factor from the bacterium E. litoralis. When illuminated with blue light, TAEL dimerizes, binds to its cognate regulatory element called C120, and activates transcription. This protocol uses transgenic zebrafish embryos that express the TAEL transcription factor under the control of the ubiquitous ubb promoter. At the same time, the C120 regulatory element drives the expression of a fluorescent reporter gene (GFP). Using a simple LED panel to deliver activating blue light, induction of GFP expression can first be detected after 30 min of illumination and reaches a peak of more than 130-fold induction after 3 h of light treatment. Expression induction can be assessed by quantitative real-time PCR (qRT-PCR) and by fluorescence microscopy. This method is a versatile and easy-to-use approach for optogenetic gene expression.

Validity Of Scoring Urine Color At Different Light Intensities To Assess Urine Concentration

PURPOSE: Light conditions may influence the accuracy and cut-off value of urine color (Uc) charts. The aim was to compare the accuracy of Uc scoring at different light conditions. METHODS: 178 previously collected samples with a median of 1.018 (IQR 1.012-1.023) urine specific gravity (USG) were stored at -20 °C. 30 mL samples were thawed and scored by 3 technicians for Uc in 16 different ways: four light conditions (fluorescent (224 lux), halogen (402 lux), LED panel light (1666 lux), and LED flashlight (1848 lux)), using two different color charts (8-color and 7-color Uc chart), and two different techniques (a sample over chart approach and a Uc scoring box). As freezing urine samples may affect Uc, the results' generalizability was analyzed using a subsample of frozen samples (n = 78) comparing to its originally measured fresh Uc based on LED panel scoring box condition. RESULTS: Aggregated Uc results were significantly different between light conditions (P < 0.01). Lower light intensity scored 1.5-2 shades darker than bright conditions, with 3.8 (2-5.5) for fluorescent light, 3.5 (2-5.8) for halogen light vs. 2.4 (1-5.2) for LED light panel, and 2.0 (1-3.5) the LED flashlight. The best diagnostic capability for identifying urine with a USG ≥1.020 using receiver operating characteristics (ROC) was found for the brightest light conditions (LED flashlight) based on an average area under the curve (AUC) of 0.86. Likewise, the optimal Uc cut-off value, obtained from ROC analysis, decreased from ≤4 (fluorescent and halogen) to ≤3 (LED conditions). The median Uc for both charts comparing fresh vs. frozen samples was 2, withthe 75th percentile for Uc +2 shades darker for frozen samples (P ≤ 0.004). Still, fresh vs. frozen samples showed a moderate (r = 0.64) to fair (r = 0.71) Spearman correlation for 8- and 7-color Uc charts, P < 0.001. The Bland-Altman analysis showed that misreporting bias (r ≤ -0.45, P < 0.001) was predominantly based on a limited number of darker scored Uc samples. CONCLUSIONS: Urine color scoring is affected by light conditions, resulting in higher accuracy and a one-shade lower Uc cut-off value at the brightest light conditions. While freezing affects Uc, these results are likely generalizable to samples measured in fresh conditions suggesting that Uc cut-off value should be adjusted to light conditions.

New mechanism of a daylighting system using optical-fiber-less design for illumination in multi-storey building

In this study, the fully new scheme of the daylighting system is devised and a few avenues are proposed toward large scale illumination area with the highly efficient luminous flux and modest cost. Rather than a previously common design, consisting of a sole system, we work out two subsystems for a generic daylighting system: outdoor and indoor subsystems. For the outdoor subsystem, aiming to guide light deeply and efficiently for a given multi-storey building, we first capitalize on a simple design of two mirrors to collect the sunlight and transport it in free-space, which negligibly penalizes the optical loss. To guide light to each particular area inside building, we further propose two options for the indoor subsystem taking into consideration between cost and performance: first with the Fresnel lens + circular plastic optical fiber (POF) bundle and second with the waveguide concentrator + flat POF bundle. The quantitative assessment unravels that the optical efficiency of the latter is higher than that of the former, 63.7 % vs 48.7 %. Still, the real implementation of the Fresnel lens + circular POF is more prone and we indeed demonstrate a principle-of-concept system. Such design also preferably implements with a LED panel, in an embodiment of a so-called hybrid daylighting system, to grant light in overcast and night-time situations. This proposed daylighting system also enables exceptional merit in calculated energy saving, up to roughly 46.5% in a year with sunlight condition as in Ho Chi Minh City (Vietnam), as electrical light is used properly and barely. All things taken into account, this approach indicates a likely perspective for fostering a new generation of the daylighting system that making use of sparingly optical fiber.

In-situ photodeposition of CoSx on Pa0.5Ba0.5Mn0.25Fe0.75O3-δ perovskite to boost bifunctional oxygen electrocatalysis for rechargeable Zn-air batteries

The single catalytic property with limited active sites severely restricts the development of perovskite materials as efficient oxygen electrocatalysts in rechargeable Zn-air batteries (ZABs). Although some researches on structural optimization and surface decoration of perovskite materials have improved their electrocatalytic performance, the complicated preparation process, and harsh treatment conditions urge the apparent of a creative attempt towards perovskite. Herein, we develop a highly-dispersed amorphous CoSx modified Pa0.5Ba0.5Mn0.25Fe0.75O3-δ composites (CoSx/PBMF) by a rapid and mild photochemistry-deposition method. The structural merit and the synergistic effect of integrating amorphous CoSx and PBMF result in a perovskite material with outstanding electrocatalytic activity and superior durability. Moreover, the liquid rechargeable ZAB assembled with integrated CoSx/PBMF electrocatalyst as air electrode demonstrates a maximal power density of 114 mW cm−2 and a long charge-discharge cycling life over 220 h with initial cycle efficiency of 60.5% and 0.03 V incensement of voltage gap. Meanwhile, the all-solid-state CoSx/PBMF-based ZABs maintain an open-circuit voltage of 3.92 V in series of three ZABs and powered LED panels stably, demonstrating its practical utility as the battery for portable electron devices.

Technical note: Calibration of frame intervals of video recorders using Global Positioning System (GPS) signal as time reference

A method has been developed for calibrating the time intervals of video recorders using a LED panel known as “SEXTA”, which utilizes Global Positioning System (GPS) signal as time reference. This method directly measures the frame intervals frame by frame down to a time resolution of 2 ms of the recordings by video recorders equipped with CCD or CMOS sensors in global shutter or rolling shutter modes respectively. The method has been validated by using a Digital Single Lens Reflex (DSLR) camera and a previous studied dashboard camera. Frame by frame analysis of the calibrated video recording of SEXTA can reveal characteristics of sensors, such as type of sensors (CMOS vs CCD), exposure time, the direction and speed of rolling shutter for CMOS sensors as well as the common characteristics of dashboard cameras such as frame skipping.

Yellow Swarm: LED panels to advise optimal alternative tours to drivers in the city of Malaga

Traffic congestion is one of the main concerns of citizens living in big cities. In this article we propose a novel system, called Yellow Swarm, with the aim of improving road traffic at a low cost and easy implementation by using a set of LED panels placed throughout the city in order to spread road traffic over its streets. The system is optimally configured by a new epigenetic algorithm which calculates the time slots for each suggested detour shown in the panels. Yellow Swarm was tested on three scenarios of the city of Malaga, Spain, using the real city layout and actual traffic flows calculated by our flow generator algorithm with data published by the city’s authorities. Our results show shorter average travel times (up to 19 s) and a reduction of greenhouse gas emissions (up to 4.5%) and fuel consumption (up to 1.6%), which have been achieved without increasing the maximum travel times (reduced by 205 s). Yellow Swarm, as a distributed traffic management system in the city, represents a major improvement that benefits drivers on long trips by reducing travel times and preventing traffic jams.