lighting systems
Recently Published Documents


TOTAL DOCUMENTS

1207
(FIVE YEARS 414)

H-INDEX

29
(FIVE YEARS 6)

Energies ◽  
2022 ◽  
Vol 15 (1) ◽  
pp. 345
Author(s):  
Tomas Novak ◽  
Petr Becak ◽  
Roman Dubnicka ◽  
Jana Raditschova ◽  
Dionyz Gasparovsky ◽  
...  

This article deals with options for how to express the luminous flux from outdoor electrical substations of the electric transmission system. Processing of the models of light emissions before and after refurbishment of lighting systems was motivated by setting out rules for the design and erection of refurbished lighting systems in outdoor electrical substations, which are most commonly built in inhabited rural areas with low luminance of the background. The proposed model and calculations are based on requirements of international standards and recommendations for lighting of outdoor workplaces as well as on internal regulations of the ČEPS (Czech Transmission System Operator). These requirements are implemented in real electrical substations and lighting models that are extended by the calculation space of the software goniophotometer. The software goniophotometer was used to evaluate light distribution characteristics of entire electric stations in various situations. This article assesses the impact of different lighting systems installed at electrical substations from the perspective of both direct and total luminous flux directed to the upper hemisphere. It takes into account three outdoor electrical substations (420 kV) of a transmission network and their lighting systems before and after refurbishment. The aim of this article is to determine to what extent the electrical substations contribute to emissions of luminous flux to the upper hemisphere. Results from calculations on models show reduced radiation to the upper hemisphere up to 52.3% after refurbishment of obsolete lighting systems, although total installed flux actually increased due to a change in the ratio of direct and reflected luminous flux after refurbishment of lighting systems.


Author(s):  
Jesús Fausto Córdova-Escobedo ◽  
Felipe Mendoza-González ◽  
Cristian Gomez-Rodriguez ◽  
Jesús Fausto Córdova-Manzo

This research evaluates the effects of color in humans generated by LED lighting systems. This evaluation allows us to know the different parameters that these systems generate, such as: the temperature and color of light suitable for human vision and thus be able to implement them in LED lighting designs for work areas. Having an adequate lighting system contributes to visual health and safety by avoiding work accidents. Each color has a different percentage of light reflection and in the same way each color affects us optically and psychologically by causing different sensations and perceptions in human beings such as visual fatigue, exhaustion, eye disorders, lacrimation, irritation, stress, migraines and even impaired vision Taking care of visual health is of vital importance. The methodology for evaluating lighting designs will be with NOM-030-ENER-2012. The contribution of this research will be to know the optimal colors and color temperature of light to use in LED lighting systems and to help lighting system designers in the selection of suitable LEDs and area colors that contribute to the visual health of humans


Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4441
Author(s):  
Valentina Pintus ◽  
Ferenc Szabó ◽  
Dávid Noel Tóth ◽  
Karin Wieland ◽  
Péter Csuti ◽  
...  

This study aims to investigate the chemical stability of some modern paint samples exposed to a new Light Emitting Diode (LED)-lighting system and a halogen lamp by using micro-attenuated total reflectance of Fourier transform infrared spectroscopy (µ-ATR-FTIR), µ-Raman, pyrolysis—gas chromatography/mass spectrometry (Py-GC/MS), and thermally assisted hydrolysis and methylation of GC/MS (THM-GC/MS). Those investigations were performed before and after the exposure of the samples to lightings for 1250, 2400, 3300, and 5000 h. The results obtained with µ-Raman spectroscopy show the high stability of the selected inorganic pigments after the exposure to the lighting systems; while similar to the UV/Vis/NIR results reported in a previous study, µ-ATR-FTIR and THM-GC/MS results evidence greater chemical changes occurring principally on the linseed oil binder-based mock-ups among the acrylic and alkyd-based samples. Moreover, principal component analyses (PCA) and hierarchical cluster analyses (HCA) of THM-GC/MS results highlight that those changes were mostly dependent on the exposure time and on the type of pigment, while being independent of the lighting system used. Finally, semi-quantitative µ-ATR-FTIR results show slight pigment enrichment at the paint surface due to the auto and photo-oxidative degradation of the linseed oil binder.


Insects ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1117
Author(s):  
Sibylle Schroer ◽  
Kat Austen ◽  
Nicola Moczek ◽  
Gregor Kalinkat ◽  
Andreas Jechow ◽  
...  

(1) The project “Tatort Streetlight” implements an insect-friendly road light design in a four year before–after, control–impact (BACI) approach involving citizen scientists. It will broaden the stakeholder interests from solely anthropogenic perspectives to include the welfare of insects and ecosystems. Motivated by the detrimental impacts of road lighting systems on insects, the project aims to find solutions to reduce the insect attraction and habitat fragmentation resulting from roadway illumination. (2) The citizen science approach invites stakeholders to take part and join forces for the development of a sustainable and environmentally friendly road lighting solution. Here, we describe the project strategy, stakeholder participation and motivation, and how the effects of the alternative road luminaire and lighting design can be evaluated. (3) The study compares the changes in (a) insect behavior, (b) night sky brightness, and (c) stakeholder participation and awareness. For this purpose, different experimental areas and stakeholders in four communities in Germany are identified. (4) The project transfers knowledge of adverse effects of improperly managed road illumination and interacts with various stakeholders to develop a new road lighting system that will consider the well-being of street users, local residents, and insects.


Author(s):  
М. В. Цибуля ◽  
І. В. Олейнікова

The main purpose of the study is to create energy-efficient solutions when designing the lighting of the entrance group for the case when the object must provide round-the-clock operation Methodology. To achieve this goal, a method for multi-level connection of light sources of different intensities has been developed. The control of the processes of level regulation is carried out using motion sensors. Results. The modern level of LED products makes it possible to use LED lighting sources as universal ones, allowing you to implement any design solution. The introduction of motion sensors as elements for regulating the intensity of light allows to obtain more than 50% energy savings. Interesting design solutions help create light accents without creating too much lighting on certain objects. Scientific novelty. The work combines multilevel lighting systems using motion sensors as switches operating at night. The authors proposed a sequence of connecting the levels of the system to create the most comfortable stay and a good first impression of the institution. Such a system makes it possible to use lighting not only for practical purposes, but also for the most attractive visual appearance. Practical significance. The versatility of this methodology allows it to be applied to objects of various purposes, including round-the-clock service. However, it is important to plan for such a lighting system even at the design stage of the building in order to obtain the maximum economic benefit.


2021 ◽  
Author(s):  
Soyhan Bagci ◽  
Astrid Wieduwilt ◽  
Ebru Aileen Alsat ◽  
Jana Blickwedel ◽  
Brigitte Strizek ◽  
...  

Abstract Maternal circadian rhythms are important for maintaining maternal and fetal homeostasis. The maternal circadian system coordinates the internal clock of the fetus with environmental lighting conditions via the melatonin signal. The intensity and wavelength of daylight influence nocturnal melatonin production. This study aims to evaluate the effect of environmental lighting conditions on melatonin production in pregnant women with reduced mobility during hospitalization. We installed a human-centric lighting system with biodynamic effects (BDL, biodynamic lighting) in the patient rooms. The pregnant women in the patient rooms with standard indoor conditions served as a control group. The illuminance (lux) and dose of effective circadian irradiation (Hec) were recorded every 10 seconds by light dosimeters (Lucerne University, Switzerland) attached to the patients` clothing. We analyzed the illuminance status of 47 pregnant women with a median (IQR) gestational age of 29.9 (25.4-32.3) weeks of gestation. The median illuminance in the control group was significantly lower (p<0.05) than in the BDL group in the morning and afternoon from day 1 to 5. BDL patients had a significantly higher effective circadian irradiation in the morning. The effective circadian irradiation showed a significant daily rhythm only in the BDL group. The BDL group had a significantly higher melatonin production on day 3 (p=0.006) and day 6 (p=0.012) than the control group (median (IQR) 15840 (10140-22160) ng vs. 6141 (2080-11328) ng/n on day 3 and 18780 (11320-23562) ng vs. 6380 (3500-17600) ng on day 6). We have demonstrated that dramatically altered lighting conditions of hospitalized pregnant women may be optimized by installing biodynamic lighting systems in the patient rooms resulting in the maintenance of nocturnal melatonin production in pregnant women.


2021 ◽  
Author(s):  
L. Giovannini ◽  
V.R.M. Lo Verso ◽  
F. Favoino ◽  
V. Serra ◽  
A. Pellegrino

The new HIEQ Lab (Health, well-being and Indoor Environmental Quality Laboratory) is presented. It is a living lab, primarily intended for research on human performance, comfort, and well-being, integrated with the energy performance in a completely controlled real space. Users are involved as active players in controlling and assessing building components and design strategies for health, well-being and IEQ requirements. Experimental activities will be addressed through a multi-domain approach that combines lighting, acoustic, air quality and thermal issues. For what concerns lighting, the laboratory is conceived to study the performance of daylighting and electric lighting systems and control solutions, focusing on the relationship between lighting conditions and human performance, comfort, and well-being. The paper reports the results of a literature review on existing lighting research facilities, and then describes the features of the new HIEQ Lab and its main research objectives, with a focus on lighting and daylighting research opportunities.


2021 ◽  
Author(s):  
M. Nilsson Tengelin ◽  
N. Mylly ◽  
P.O. Hedekvist

This paper reports the result of a survey on entertainment lighting distributed to 246 museums and 56 theatres in Sweden. The questions concerned the lighting technology used, experience from changing lighting systems, plans, problems, apprehensions and expectations. The replies showed that the transition to LED has been much faster in museums than in theaters and 35% of the theatres do not plan for a transition to LED. Reasons given are economy, light quality, and dimming functionality. Lighting professionals are generally sceptical in exchanging halogen lights. The artistic expression in lighting design goes beyond the specifications and what is promised in the data sheet. To facilitate a smoother transition to modern lighting technologies, the quality of the white light and proper function of the luminaires must be ensured and the communication between the manufacturers, retailers, lighting professionals and other artistic functions must be improved.


2021 ◽  
Author(s):  
D. Durmus

Smart lighting systems are based on sensors and tunable lighting systems are increasingly more prevalent, but collecting, analysing, and using the large data generated by these sensors are challenging. Inspired by research on evolutionary algorithms, it can be hypothesized that an adaptive lighting system can operate in real-time by adjusting its output through a decision-making algorithm based on data mining techniques. Such an adaptive lighting system requires two-order input from users; initial and continual. Initial conditions provide training to the system through human factors research investigating the interaction between humans and their environment. Continual conditions are provided by data collected through sensors in real-time, and they continuously feed into the decision-making algorithm to adjust the output to meet occupants’ biological and psychological needs. Research indicates that artificial intelligence techniques, such as evolutionary algorithms, can emerge as good candidates for this framework.


Sign in / Sign up

Export Citation Format

Share Document