Types Of Lamps Research Articles

Improvement of temporal light artefact effects in commercial LED lamps

Temporal light modulation and its potential adverse visual effects on human observers, collectively known as temporal light artefacts (TLAs), have been limited by the European Union Ecodesign regulation. Limitations on two key TLA metrics, flicker and stroboscopic effect, were introduced in September 2021. This study analyses the impact of this regulation on commercial LED lamps by measuring multiple different consumer-grade LED E27 retrofit lamps by several manufacturers before and after the regulation. The lamps purchased after the Ecodesign regulation seem to favour a certain type of LED driver that provides the best TLA behaviour of all lamp types. The regulation, with respect to TLA, has resulted in the replacement of ill-behaving lamp types in the market by newer lamps with better TLA characteristics.

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.

High efficacy of red light photodynamic therapy with 10 % aminolevulinic acid gel irrespective of the extent of keratinocyte atypia in actinic keratosis – exploratory post-hoc analysis of three pivotal phase III trials

BackgroundPrimary endpoints of clinical studies investigating treatments for actinic keratosis (AK) are mainly based on clinical evaluation, but a recent study showed that in AK, clinical classification according to Olsen and the extent of keratinocyte atypia do not necessarily correlate. The influence of the epidermal extent of atypia on treatment efficacy is usually not investigated and therefore remains largely unknown. ObjectiveTo evaluate whether the extent of keratinocyte atypia influences efficacy of photodynamic therapy (PDT) when treating AK. MethodsWe performed a post-hoc analysis of histological (keratinocyte intraepithelial neoplasia (KIN)), and clinical (Olsen) data of biopsied lesions of three pivotal studies evaluating PDT using 10 % aminolevulinic acid (ALA) gel or vehicle and narrow- or broad-spectrum red light lamps. ResultsOverall, 514 biopsied lesions were considered. Clearance rates after red light PDT with 10 % ALA gel were comparable for KIN I-III (88.2 %, 92.0 % and 87.9 %) and Olsen I-II lesions for any given lamp type. Generally, clearance rates were higher using narrow- compared to broad-spectrum lamps. For both lamp types, the variation in clearance rates from KIN I-III was low. Clearance was lower with vehicle. LimitationsVarying lesion numbers in the subgroups and a remaining risk of bias due to the biopsies are potential limitations. ConclusionOur results suggest that red light PDT with 10 % ALA gel is an effective treatment option for AK regardless of the extent of keratinocyte atypia.

A comprehensive evaluation of enhanced temperature influence on gas and aerosol chemistry in the lamp-enclosed oxidation flow reactor (OFR) system

Abstract. Oxidation flow reactors (OFRs) have been extensively utilized to examine the formation of secondary organic aerosol (SOA). However, the UV lamps typically employed to initiate the photochemistry in OFRs can result in an elevated reactor temperature when their implications are not thoroughly evaluated. In this study, we conducted a comprehensive investigation into the temperature distribution within an Aerodyne potential aerosol mass OFR (PAM-OFR) and then examined the subsequent effects on flow and chemistry due to lamp heating. A lamp-induced temperature increase was observed, which was a function of lamp-driving voltage, number of lamps, lamp types, OFR residence time, and positions within the PAM-OFR. Under typical PAM-OFR operational conditions (e.g., < 5 d of equivalent atmospheric OH exposure under low-NOx conditions), the temperature increase typically ranged from 1–5 °C. Under extreme (but less frequently encountered) conditions, the heating could reach up to 15 °C. The influences of the increased temperature over ambient conditions on the flow distribution, gas, and condensed-phase chemistry within PAM-OFR were evaluated. Our findings indicate that the increase in temperature altered the flow field, resulting in a diminished tail on the residence time distribution and corresponding oxidant exposure due to faster recirculation. According to simulation results from a radical chemistry box model, the variation in absolute oxidant concentration within PAM-OFR due to temperature increase was minimal (< 5 %). The temperature influences on seed organic aerosol (OA) and newly formed secondary OA were also investigated, suggesting that an increase in temperature can impact the yield, size, and oxidation levels of representative biogenic and anthropogenic SOA types. Recommendations for temperature-dependent SOA yield corrections and PAM-OFR operating protocols that mitigate lamp-induced temperature enhancement and fluctuations are presented. We recommend blowing air around the reactor's exterior with fans during PAM-OFR experiments to minimize the temperature increase within PAM-OFR. Temperature increases are substantially lower for OFRs utilizing less powerful lamps compared to the Aerodyne version.

The power of spectrally enhanced artificial night-time lights data: Assessing NTL risks along the urban-natural interface

Artificial night-time lights (NTL) have long been known for their adverse effects on humans and the environment. Recent studies report that the severity of NTL impact on organisms is associated not only with its intensity but also a spectrum. The spectral resolution of freely available satellite NTL data is restricted to red, green, and blue sub-spectra, which are significantly wider than the ranges of vulnerability, reported by laboratory studies for various species. The present study is the first attempt to overlap spectrum-specific NTL data, describing the intensities of light emitted by different lamp types with relatively narrow emission peaks, with the sites where species vulnerable to specific NTL sub-spectra were detected. We overlap those light intensity maps with increasingly detailed maps of natural areas located along the urban-natural interface of the Haifa region. We analyze light pollution in the ecological corridors, which host numerous species with different, but unknown, spectrum-specific effects of NTL (a coarse-level analysis), and in the sites of several species, with either known or unknown spectrum-specific effects of NTL (a fine-level analysis). We show that a considerable part of the ecological corridors is polluted by metal halide and high-pressure sodium lamps which may negatively influence plants, bees, sea turtles, birds, and mammals. One habitat site of the Near Eastern fire salamander (Salamandra infraimmaculata) is polluted by lamps with green-light emission peaks which may explain the low reproductive success of this population. Despite the study limitations, related to the region-specific NTL data of spectrum-specific resolution and scarcity of evidence about the spectrum-specific NTL harmful effects on organisms, we believe that the obtained results would contribute to the elaboration of more informed fine-tuned artificial lighting policies which would diminish the burden of urban built-up zones on their neighboring natural areas.

Comparative Life Cycle Assessment of Four Municipal Water Disinfection Methods

The disinfection of treated water is an important process to provide healthy water to the public. The chosen disinfection methods can vary depending on the water source, regulations, targeted microorganisms, operating conditions, capital costs and operation and maintenance costs. Another important factor for decision-makers is the environmental impacts caused by the disinfection process. This paper will reveal the life cycle assessment (LCA) of four different water disinfection scenarios at a municipal scale from the operational phase. A comparison is made between chlorination systems, two ultraviolet disinfection systems that use different types of lamps and an ozonation system. The results demonstrate that the UV disinfection system with low-pressure lamps had the lowest environmental impact across all categories, followed by chlorination. In contrast, the ozonation system and the UV disinfection system with LED lamps showed the highest impacts in all categories, primarily due to their high electricity consumption. Changes in the electricity mix had a substantial influence on the impact categories for all disinfection methods, but the gradation of the water disinfection methods was not that significant. Studies on the environmental impacts of the water disinfection process need to be carried out for larger flow rates to increase the information on this topic.

Modeling Night and Daylighting Toll Road Tunnel Using Dialux to Compare the Performance of HPS and LED Lamp

In toll road tunnels, the lighting at the threshold zone must balance the brightness of the access zone with natural light. Therefore, artificial lighting is strategically placed in that area to match the brightness to the intensity of natural light. This balance shifts during nighttime to ensure uniform brightness throughout the tunnel, equivalent to street lighting. Additionally, a significant amount of power is required to realize this artificial lighting. Two lamp technologies are used for tunnel lighting: HPS lamps with low energy efficiency and LED lamps with better energy efficiency. The challenge is determining artificial lighting in the threshold zone using energy-efficient lamps. To address this issue, simulations were conducted to compare the two lamp types applied in tunnels to achieve the most significant power savings. This research creates a model of toll road tunnel lighting using DIALux software better to understand the characteristics of toll road tunnel lighting using HPS and LED lamps. The SNI and ANSI/IES are the standards used. The Cisumdawu tunnel is used as the case study. The simulation results show that the luminance in the interior zone using LED or HPS lamps meets the SNI standard. Using LED lamps results in higher luminance with less power than using HPS. This discovery can improve energy efficiency in tunnel environments and contribute to lighting solutions for transportation infrastructure.

Performance of high-efficiency UV-C LEDs in water disinfection: Experimental, life cycle assessment, and economic analysis of different operational scenarios

The widespread use of low or medium pressure mercury lamps in UV-C water disinfection should consider recent advances in UV-C LED lamps that offer a more sustainable approach and avoid its main drawbacks. The type of water and the mode of operation are critical when deciding on the treatment technology to be used. Therefore, this study investigates the potential application of UV-C LED disinfection technology in terms of kinetics, environmental assessment, and economic analysis for two scenarios: the continuous disinfection of a wastewater treatment plant (WWTP), and disinfection of harvested rainwater (RWH) in a residential household that operates intermittently. Experiments are conducted using both the new UV-C LED system and the conventional mercury lamp to disinfect real wastewater. Removal of total coliforms and Escherichia coli bacteria, with concentrations of approximately 105 and 104 CFU per 100 mL has been followed to assess the performance of both types of UV-C lamps. The experimental study provides kinetic parameters that have been further used in the environmental assessment conducted from a life cycle perspective. Additionally, considering the significant role of electricity consumption, a preliminary economic analysis has been conducted. The results indicate that first-order kinetic constants of pathogens removal with UV-C LEDs achieve 1.4 times higher values than Hg lamp. Regarding the environmental and economic assessment, for disinfection systems operating continuously, LEDs result in environmental impacts 5 times higher than Hg lamp in most categories, indicating that Hg lamps offer a viable option both from economic and environmental point of view. However, for installations with intermittent operation, LEDs emerge as the most competitive alternative, due to their ability to be turned on and off without affecting their lifespan. This study shows that UV-C LED lamps hold promise to replace conventional mercury lamps in a near future.

Efficacy and Optimal Timing of Warm-white or Red + Far-red LED Lamps in Regulation of Flowering in Long-day Ornamentals

When natural days are short, photoperiodic lighting at the end or beginning of the day (day extension) or in the middle of the night (night break) promotes flowering of long-day plants. The objective of this study was to compare broad-spectrum warm-white light-emitting diodes (LEDs) and red (R) + far-red (FR) LEDs at flowering regulation when delivered at different timings in the night period. We performed a greenhouse experiment on four long-day ornamentals [coreopsis (Coreopsis grandiflora) ‘Early Sunrise’, snapdragon (Antirrhinum majus) ‘Liberty Classic Yellow’, petunia (Petunia ×hybrida) ‘Easy Wave Burgundy Star’, and petunia ‘Wave Purple Improved’]. We grew plants under a truncated 8-hour photoperiod with or without low-intensity (∼2 μmol·m−2·s−1) nighttime lighting from warm-white or R+FR LEDs. For each light quality, we delivered four timings: 1) 8 hours after dusk; 2) 8 hours before dawn; 3) 4 hours after dusk + 4 hours before dawn; and 4) 4-hour night break. The effectiveness of floral promotion was determined by time from the treatment onset to the first open flower. Coreopsis flowered similarly under all lighting treatments, irrespective of light quality and timing, but did not flower under the short-day treatment by the end of the experiment. At flowering, coreopsis was 18% to 19% shorter under white than R+FR LEDs. In contrast, snapdragon flowered 9 to 20 days later under white than R+FR LEDs, when delivered for 8 hours at night, but flowered similarly under these two lamp types as a 4-hour night break. Compared with the short-day treatment, white and R+FR LEDs promoted flowering of both petunia cultivars, although flowering generally occurred later under white than R+FR LEDs. Snapdragon and petunia ‘Easy Wave Burgundy Star’ developed 30% to 122% more lateral branches under white than R+FR LEDs, when delivered for 8 hours at night. The effectiveness of warm-white LEDs was generally unaffected by timing, although it was most promotive of flowering in snapdragon when delivered for 8 hours before dawn. For R+FR LEDs, 8-hour day-extension lighting was generally more effective than 4-hour night-break lighting, irrespective of timing. We conclude when delivered for 8 hours at night, warm-white LEDs are generally less effective than R+FR LEDs at promoting flowering of long-day ornamentals but similarly effective as 4-hour night-break lighting. The effectiveness of day-extension lighting is generally independent of timing, although for R+FR LEDs, 8 hours after-dusk and/or before-dawn lighting was generally more effective than 4-hour night-break lighting.

ANALISIS PENCAHAYAAN LAMPU PENERANGAN JALAN UMUM (LPJU) PADA JALAN TOL SEMAYANG

Several issues with public street lighting are often found and do not meet the Indonesian National Standard (SNI). Common problems include uneven spacing between streetlight poles, improper pole heights, poorly organized streetlight installations, and incorrect selection of lamp types and wattages according to the SNI standards. The lack of streetlights on busy road sections results in inefficient operation and discomfort for road users due to inadequate light intensity at the streetlight locations caused by various factors. To address these issues, solutions are needed to improve the existing situation, including energy-saving measures for public street lighting. Some necessary actions include replacing non-compliant streetlights and conducting evaluations by relevant authorities after installation works are completed. The existing condition of streetlights along the Semayang Toll Road shows an average illumination level produced by 150W SON-T lamps of 3.1 lux with light uniformity of 0.0, which does not comply with SNI 7391:2008. Simulation results using Dialux 4.13 software indicate that the average illumination level produced by Philips LED luminaires of 150W is 11 lux with a light uniformity of 0.106 lux, meeting SNI 7391:2008 requirements. Similarly, for Philips LED luminaires of 120W, the average illumination level is 11 lux with a light uniformity of 0.114 lux, thus meeting the standards. Based on the simulation results using Dialux 4.13 software, the use of 120W LED lamps for public street lighting on the Semayang Toll Road can lead to a 20% reduction in electricity consumption.

Replacement of tubular fluorescent lamps with tubular LEDs lamps and daylight integration in classrooms and laboratories

The quality of lighting significantly influences our ability to perform tasks in enclosed spaces, and certain characteristics of lighting sources play a crucial role. Light-emitting diode (tubular LED) lamps offer advantages for both home and office use. Choosing tubular LED lamps over fluorescent ones is beneficial for several reasons. Tubular LEDs are mercury-free, ensuring environmental safety compared to the small amount of mercury present in fluorescent tubes. Furthermore, tubular LEDs provide directional lighting, minimizing light loss in fixtures and unnecessary areas, and offering better efficiency (around 40% more than tubular fluorescent lamps). Also, they produce high-quality light with various color temperatures, eliminating flickering issues that can cause discomfort such as eye strain, headaches, and migraines. Additionally, tubular LEDs have a longer lifespan making them a preferable lighting option. The superior quality of natural light makes it the optimal source of illumination, which matching well with the visual response of the human eyes. Daylight has a positive influence on people, instilling a feeling of vibrancy and brightness within their living environment. The acknowledged benefits of daylight extend to enhancing visual comfort, promoting health, and improving overall performance among building occupants. This paper focuses on the integration of natural daylight with artificial light, particularly through tubular LED lamps, and investigates the daylight factor. Two groups of six tubular LED lamps (60cm with 9 Watt and 120cm with 18 Watt) and another group of six tubular fluorescent lamps (60cm with 18 Watt and 120cm with 36 Watt) were studied. The study involved two sets of six tubular LED lamps (60cm with 9W and 120cm with 18W) and another set with six tubular fluorescent lamps (60cm with 18W and 120cm with 36W). Measurements were conducted using Spectroradiometer Ocean Optics HR 2000 with 4.7% uncertainty and a photometric bench to assess the spectral output. Additionally, UVA/B silicon detector and Luxmeter detector setups with uncertainties of 5.2% and 6%, respectively, were employed for irradiance and illuminance measurements of tubular LEDs and fluorescent lamps. Various parameters, including daylight factor ratio, UVA power to luminous flux (K) for tubular fluorescent lamps, spectral power distribution, and illumination levels were obtained. Integration between daylight and tubular LED lamps was also determined. The maximum detected value lmW /013.0  is less than the safe limit for human health but still there are effects on human health if they use these types of lamps. Therefore, it is advisable to switch from tubular fluorescent lamps to tubular LEDs to mitigate the impact of UVA on human health and the environment.

PENGARUH VARIASI DAYA DAN LAMA WAKTU KONTAK LAMPU ULTRAVIOLET TIPE C PADA LEMARI STERILISASI TERHADAP PENURUNAN JUMLAH KUMAN PADA ALAT MAKAN DI KANTIN OFFICE PT.X

The problem of food sanitation hygiene was very important to be addressed, especially in food management facilities such as office canteens. It was found that the number of germs on cutlery in the PT X canteen exceeded the established quality standard, namely 150 colonies/cm2. Attempts to reduce the number of germs on the cutlery of dishes by sterilization using UV-C light. This study aims to determine the variation in power and the length of contact time of ultraviolet lamp type C (UV-C) using a sterilization cabinet against reducing the number of germs on the cutlery at PT.X This type of research is an experiment with a posttest with control design. The cutlery used as a sample was 25 pieces. Data analysis was bivariate statistic analysis. Based on the results, it was known that there was a decrease in the number of germs after UV-C light irradiation was carried out. Irradiation with a power of 15 watts long contact 25 minutes lowers the number of germs 96.89%, Irradiation with a power of 15 watts long contact 30 minutes lowers the number of germs 98.65%, Irradiation with a power of 30 watts long contact 25 minutes lowers the number of germs 99.89%, and Irradiation with a power of 30 watts long contact 30 minutes decreases the number of germs 100%. A decrease in the number of effective germs occurs at a lamp power of 30 watts with a time contact duration of 30 minutes.

Method for the production of a compact source of atomic line spectra in the vacuum ultraviolet

Atomic emission spectra provide a means to identify and to gain insight into the electronic structure of emitting or absorbing matter. Detailed procedures are provided for the construction of low-pressure electrodeless discharge lamps that yield targeted emission in the vacuum ultraviolet for the spectroscopic study of water vapor and halogen species aboard an array of airborne observation platforms in the upper atmosphere, as well as in laboratory environments. While specific to the production of Lyman-alpha, atomic chlorine, and atomic bromine emissions in this study, the configuration of the lamps and their interchangeability with respect to operation lend these procedures to constructing sources engaging a wide selection of atomic and molecular spectra with straightforward modifications. The features and limitations of each type of lamp are discussed, as well as methods to improve spectral purity and factors affecting operational lifetime.

Research on Optimization of University Classroom Lighting Environment Based on Computer Simulation

In order to improve the comfort of classroom users and improve the lighting environment of university classrooms, this paper puts forward different optimization schemes based on computer simulation. Dialux, a lighting environment design software, is used to numerically simulate the lighting environment of university classrooms. The classroom lighting scheme is optimized and different solutions are proposed. Through computer simulation, the effect of lighting is compared and analyzed, in order to find the most beneficial scheme for students’ mental health, which provides the basis for intelligent control of classroom lighting. The results show that the average illuminance decreases with the increase of suspension height, and the illuminance uniformity increases first and then decreases with the increase of suspension height. The solution of adjusting the projection direction and surface reflectivity of lamps is not suitable, and upgrading the type of lamps can solve the lighting environment problems and control glare. Increasing the number of lamps and adjusting the arrangement of lamps can improve the lighting environment, increase the average value but reduce the uniformity, but lead to a significant increase in energy consumption. Intelligent control based on computer simulation can solve the coordination problem of energy consumption and lighting effect. Through comparative analysis of the effects of different schemes on the classroom lighting environment in colleges and universities based on computer simulation, this paper provides data support for the selection of improved schemes, which is conducive to the selection of more suitable intelligent lighting control schemes, to ensure students’ mental health and work efficiency, and has certain reference significance for creating a healthy and comfortable classroom lighting environment.

Phototherapy for vitiligo: A narrative review on the clinical and molecular aspects, and recent literature.

Vitiligo is characterized by depigmented patches resulting from loss of melanocytes. Phototherapy has emerged as a prominent treatment option for vitiligo, utilizing various light modalities to induce disease stability and repigmentation. This narrative review aims to explore the clinical applications and molecular mechanisms of phototherapy in vitiligo. The review evaluates existing literature on phototherapy for vitiligo, analyzing studies on hospital-based and home-based phototherapy, as well as outcomes related to stabilization and repigmentation. Narrowband ultra-violet B, that is, NBUVB remains the most commonly employed, studied and effective phototherapy modality for vitiligo. Special attention is given to assessing different types of lamps, dosimetry, published guidelines, and the utilization of targeted phototherapy modalities. Additionally, the integration of phototherapy with other treatment modalities, including its use as a depigmenting therapy in generalized/universal vitiligo, is discussed. Screening for anti-nuclear antibodies and tailoring approaches for non-photo-adapters are also examined. In conclusion, this review provides a comprehensive overview of phototherapy for vitiligo treatment. It underscores the evolving landscape of phototherapy and offers insights into optimizing therapeutic outcomes and addressing the challenges ahead. By integrating clinical evidence with molecular understanding, phototherapy emerges as a valuable therapeutic option for managing vitiligo, with potential for further advancements in the field.

Implementation of Energy Efficiency and Visual Comfort in Malang’s Foreign Exchange Office Lighting

The Victory International Futures office is running on foreign exchange. It is located in East Java, Indonesia, in Malang. The furniture in this office has an HPL finish, which is typically dark and has a brown cotton color. The light source’s reflections will be lessened as a result. The southeast-facing Victory International Futures building has good lighting. However, the lighting may be improved due to the limited artificial lighting offered in some areas and the absence of windows, which prevents daytime sunshine from reaching its full potential. Using windows where none are present results in an improper exchange of air coming in and going out. This study intends to ascertain the effects on workers caused by the influence of office air circulation and light intensity. This study’s technique, a case study, requires that we visit the office right away. Data gathering methods included surveys, interviews, and using the Light Metre program to gauge light intensity. According to the test results, the typical room has more light than it needs at night. Through smart lighting, this research proposes designs to enhance the quality of conference room interiors, particularly lighting design. A standard light distribution of 73,9 lux is achieved by simulating one type of lamp already present in the space using the Light Metre application.

Discussion Abounds on the Potential Carcinogenic Risks Associated With the Use of UV Curing Lamps for Permanent Nail Polish

BackgroundControversy has recently broken out over the potential carcinogenic risk associated with exposure to UV lamps for permanent nail polish. The new LED-based polymerization devices, and their potential biological effect has not been analyzed to this date. ObjectiveTo evaluate the emission power and its potential biological effects on the skin of 2 types of UV LED and fluorescent curing lamps under normal use conditions compared to doses of sunlight exposure. Material and methodsThe emission spectrum (290nm to 450nm) of curing lamps and the Sun at noon on an average summer day in mid-latitude Spain was analyzed. The effective biological irradiance potential for erythema, non-melanoma skin cancer, DNA damage, photoimmunosuppression and permanent pigmentation was also characterized. ResultsThe high-energy UVA-visible irradiance emitted by these devices was similar to the one coming from the Sun in that spectral range while the effective biological doses were lower or similar to those also coming from the Sun. The total UV and high-energy visible dose per manicure session corresponded to that obtained from 3.5min to 6min exposures to the Sun at noon in the summer days at our latitudes. ConclusionsThe exposure times and doses received with the common use of artificial lamp nail drying correspond to sunlight exposures of 3min to 5min in the central hours of the day. This represents a very low carcinogenic potential compared to sunlight exposure, although similar regarding immunosuppressive potential. Photoprotective measures would further minimize the risks.

A Retrofit Streetlamp Monitoring Solution Using LoRaWAN Communications

Ubiquitous street lighting is essential for urban areas. While nowadays, LED-based “smart lamps” are commercially available, municipalities can only switch to them in the long run due to financial constraints. Especially, older types of lamps require frequent bulb replacements to maintain the lighting infrastructure’s function. To speed up the detection of defects and enable better planning, a non-invasively retrofittable IoT sensor solution is proposed that monitors lamps for defects via visible light sensors, communicates measurement data wirelessly to a central location via LoRaWAN, and processes and visualizes the resulting information centrally. The sensor nodes are capable of automatically adjusting to shifting day- and nighttimes thanks to a second sensor monitoring ambient light. The work specifically addresses aspects of energy efficiency essential to the battery-powered operation of the sensor nodes. Besides design considerations and implementation details, the paper also summarizes the experimental validation of the system by way of an extensive field trial and expounds upon further experiences from it.

Controversias sobre los riesgos procarcinogénicos asociados al uso de lámparas ultravioleta polimerizadoras para el esmaltado permanente de uñas

BackgroundControversy has recently broken out over the potential carcinogenic risk associated with exposure to UV lamps for permanent nail polish. The new LED-based polymerization devices, and their potential biological effect has not been analyzed to this date. ObjectiveTo evaluate the emission power and its potential biological effects on the skin of 2 types of UV LED and fluorescent curing lamps under normal use conditions compared to doses of sunlight exposure. Material and methodsThe emission spectrum (290nm to 450nm) of curing lamps and the Sun at noon on an average summer day in mid-latitude Spain was analyzed. The effective biological irradiance potential for erythema, non-melanoma skin cancer, DNA damage, photoimmunosuppression and permanent pigmentation was also characterized. ResultsThe high-energy UVA-visible irradiance emitted by these devices was similar to the one coming from the Sun in that spectral range while the effective biological doses were lower or similar to those also coming from the Sun. The total UV and high-energy visible dose per manicure session corresponded to that obtained from 3.5min to 6min exposures to the Sun at noon in the summer days at our latitudes. ConclusionsThe exposure times and doses received with the common use of artificial lamp nail drying correspond to sunlight exposures of 3min to 5min in the central hours of the day. This represents a very low carcinogenic potential compared to sunlight exposure, although similar regarding immunosuppressive potential. Photoprotective measures would further minimize the risks.

EFFECT OF LIGHTING LEVELS AND LAMP TYPES FOR CRIME PREVENTION IN THAI PEDESTRIAN WALKWAYS

The effects of illuminance level and lamp type were investigated for crime prevention in Thai pedestrian walkways aimed to examine the effects of illuminance on perceived safety, pedestrian behaviour, and criminal identification as part of crime prevention. Laboratory tests were carried out at the Faculty of Architecture, Kasetsart University. Five levels of illuminance: 10, 20, 50, 100, and 200 lux, and the types of lamps—HPS, LED Daylight and LED Warm White were investigated. Experimental tests were performed using a 3D model with DIALux simulation. Results showed that each lamp type required a different illuminance to optimize crime prevention. The HPS lamp with an illuminance of 200 lux was found to be the most suitable level for perceived safety, while 10 lux was suitable for pedestrian behaviour and 10 lux was suitable for criminal identification. For the LED Daylight lamp, the illuminance of 200 lux was the most appropriate level for perceived safety, while 20 lux was suitable for pedestrian behaviour and 10-20 lux was enough for criminal identification. For the LED Warm-white lamp, the illuminance of 10 lux was the most appropriate level for perceived safety, with 20 lux for pedestrian behaviour, and 10-20 lux for criminal identification.