Human Factors Impacts of Light-Emitting Diode Airfield Lighting

2017 ◽  
Vol 2626 (1) ◽  
pp. 51-57 ◽  
Author(s):  
John D. Bullough
Keyword(s):  
Human Factors ◽  
Experimental Evidence ◽  
Energy Use ◽  
Light Emitting Diode ◽  
Light Sources ◽  
Light Emitting ◽  
Incandescent Light ◽  
Color Identification ◽  
Lighting Systems ◽  
Maintenance Requirements

Light-emitting diodes (LEDs) differ from incandescent light sources in several ways that are relevant to energy and maintenance requirements of airfield lighting systems. They have higher luminous efficacy and, when designed properly, have longer useful operating lives; both factors make LEDs attractive candidates for airfield lighting. The photometric, colorimetric, and temporal characteristics of LEDs also differ from those of incandescent light sources, and these can have important implications for the appearance of runway and taxiway lighting systems. The present paper reviews publications summarizing experimental and analytical investigations designed to assess these implications with respect to the following human factors impacts: color identification, brightness and glare, visibility in fog and haze, response to onset of flashing lights, and stroboscopic effects such as the phantom array. Overall, this review of experimental evidence suggests that, in addition to their reduced energy use and maintenance requirements, LED airfield lighting can be advantageous in comparison with incandescent lighting systems used to delineate airport runways and taxiways.

DESIGN AND IMPLEMENTATION OF A PID-BASED LUMINANCE CONTROL AND LIGHT SENSING USING SMOOTHING AVERAGING TECHNIQUE

2016 ◽  
Vol 78 (6-3) ◽  
Author(s):  
Editha Macorol ◽  
Favis Joseph Balinado ◽  
Leo M. Flores ◽  
Ezekiel V. Pascual ◽  
Christian M. Silva ◽  
...  
Keyword(s):  
Light Emitting Diode ◽  
Luminance Level ◽  
Light Sources ◽  
Averaging Technique ◽  
Light Emitting ◽  
Incandescent Light ◽  
Light Sensing ◽  
Light Stimuli ◽  
Compact Fluorescent Lamp ◽  
Global Energy Consumption

Nowadays, lighting shares a large part in the global energy consumption, lighting consumption can be easily reduced with the use of efficient light sources. The most commonly used light source is the incandescent light bulb. As time passed by, Compact Fluorescent Lamp and Light Emitting Diode use became prevalent because of their advantages over the incandescent light. The researchers were able to develop and implement a PID controlled lighting system using Light Emitting Diode utilizing the smoothing-averaging technique in its sensors. Tests were done with the system with and without smoothing technique to identify the effect of the technique used. The system automatically varies its light intensity output depending on the light stimuli maintaining the luminance level of the laboratory based on standards.

scholarly journals Impacts of average illuminance, spectral distribution, and uniformity on brightness and safety perceptions under parking lot lighting

2019 ◽  
Vol 52 (5) ◽  
pp. 626-640 ◽  
Author(s):  
JD Bullough ◽  
JD Snyder ◽  
K Kiefer
Keyword(s):  
Spectral Distribution ◽  
Energy Use ◽  
Light Emitting Diode ◽  
Light Level ◽  
Scale Model ◽  
Light Emitting ◽  
Safety Perceptions ◽  
Balancing Energy ◽  
Parking Lot ◽  
Lighting Systems

In addition to supporting visibility, parking lot lighting should enable people to feel safe and secure while they are walking through a parking lot at night. Previously published research has indicated that perceptions of safety and security under outdoor illumination are correlated with perceptions of scene brightness, which in turn are influenced by the light level in the lot, by the spectral distribution of the illumination, and the uniformity of illumination. However, the interactions and interplay among these factors are not well understood. To address this knowledge gap, two laboratory experiments were conducted using a scale model parking lot scene and a controllable light-emitting diode (LED) lighting system that allowed parametric variations in light level, spectrum and uniformity. From the results, a mathematical model of overall brightness and safety perceptions was developed to predict how different lighting configurations are perceived. The model can be used to help specifiers select lighting systems for parking lot illumination that meet the objectives of reinforcing sensations of personal safety while balancing energy use and cost concerns.

scholarly journals Plant Productivity in Response to LED Lighting

HortScience ◽  
2008 ◽  
Vol 43 (7) ◽  
pp. 1951-1956 ◽  
Author(s):  
Gioia D. Massa ◽  
Hyeon-Hye Kim ◽  
Raymond M. Wheeler ◽  
Cary A. Mitchell
Keyword(s):  
Plant Growth ◽  
Crop Production ◽  
Energy Use ◽  
Sole Source ◽  
Light Sources ◽  
Lighting System ◽  
Light Emitting ◽  
Agriculture Industry ◽  
Lighting Systems ◽  
Kennedy Space

Light-emitting diodes (LEDs) have tremendous potential as supplemental or sole-source lighting systems for crop production both on and off earth. Their small size, durability, long operating lifetime, wavelength specificity, relatively cool emitting surfaces, and linear photon output with electrical input current make these solid-state light sources ideal for use in plant lighting designs. Because the output waveband of LEDs (single color, nonphosphor-coated) is much narrower than that of traditional sources of electric lighting used for plant growth, one challenge in designing an optimum plant lighting system is to determine wavelengths essential for specific crops. Work at NASA's Kennedy Space Center has focused on the proportion of blue light required for normal plant growth as well as the optimum wavelength of red and the red/far-red ratio. The addition of green wavelengths for improved plant growth as well as for visual monitoring of plant status has been addressed. Like with other light sources, spectral quality of LEDs can have dramatic effects on crop anatomy and morphology as well as nutrient uptake and pathogen development. Work at Purdue University has focused on geometry of light delivery to improve energy use efficiency of a crop lighting system. Additionally, foliar intumescence developing in the absence of ultraviolet light or other less understood stimuli could become a serious limitation for some crops lighted solely by narrow-band LEDs. Ways to prevent this condition are being investigated. Potential LED benefits to the controlled environment agriculture industry are numerous and more work needs to be done to position horticulture at the forefront of this promising technology.

scholarly journals Revision of Smart Street Lighting LED

2019 ◽  
Vol 15 (28) ◽  
Author(s):  
Diego Julián Rodríguez Patarroyo ◽  
Iván Felipe Cely Garzón ◽  
Cristhian Alexander Letrado Forero
Keyword(s):  
Energy Efficiency ◽  
Energy Use ◽  
Light Emitting Diode ◽  
Lighting System ◽  
Street Lighting ◽  
Light Emitting ◽  
The World ◽  
Current Context ◽  
Lighting Systems ◽  
And Performance

Introduction: This Literature Review article is the result of a research on the current situation of smart public lighting systems with light-emitting diode (LED) technology in cities around the world. Problem: How convenient is it to use smart public lighting system with LED luminaires? Objective: To review the context of smart public lighting with LED technology. Methodology: Within this project, a lit review was conducted with more than 50 academic articles found in different databases such as: IEEE Xplore, Scopus, ScienceDirect etc. The selection criteria of the information followed the revision of articles from 2006 to 2018, and also, took into account their installation and performance in different cities and places of the world. Furthermore, articles on polluting and inefficient technologies were excluded. Conclusion: Considering the current context in which LED smart public lighting is, it is more likely to be implemented in the future. Results: Smart LED street lighting systems are more efficient in energy use, leads to savings in costs in medium terms, and finally, present a lower environmental impact compared to conventional lighting systems. Limitations: The review focuses on energy efficiency and economic aspects, not on social aspects. Originality: Smart LED public lighting systems have been researched within the economic and energy efficiency context.

Organic Light Emitting Diodes - Innovative Light Sources

2019 ◽  
pp. 101-107
Author(s):  
Sergei A. Stakharny
Keyword(s):  
Light Source ◽  
Organic Light Emitting Diodes ◽  
Organic Leds ◽  
Light Sources ◽  
High Quality ◽  
Light Emitting ◽  
Organic Light ◽  
Lighting Systems ◽  
Physical Principles ◽  
Prospects Of Application

This article is a review of the new light source – organic LEDs having prospects of application in general and special lighting systems. The article describes physical principles of operation of organic LEDs, their advantages and principal differences from conventional non-organic LEDs and other light sources. Also the article devoted to contemporary achievements and prospects of development of this field in the spheres of both general and museum lighting as well as other spheres where properties of organic LEDs as high-quality light sources may be extremely useful.

scholarly journals A Supervisory Control Strategy for Improving Energy Efficiency of Artificial Lighting Systems in Greenhouses

Energies ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 202
Author(s):  
Gianluca Serale ◽  
Luca Gnoli ◽  
Emanuele Giraudo ◽  
Enrico Fabrizio
Keyword(s):  
Control Strategy ◽  
Light Emitting Diode ◽  
Cost Savings ◽  
Energy Performance ◽  
Lighting System ◽  
Light Emitting ◽  
Artificial Lighting ◽  
Lighting Control ◽  
Lighting Systems ◽  
Power Densities

Artificial lighting systems are used in commercial greenhouses to ensure year-round yields. Current Light Emitting Diode (LED) technologies improved the system efficiency. Nevertheless, having artificial lighting systems extended for hectares with power densities over 50W/m2 causes energy and power demand of greenhouses to be really significant. The present paper introduces an innovative supervisory and predictive control strategy to optimize the energy performance of the artificial lights of greenhouses. The controller has been implemented in a multi-span plastic greenhouse located in North Italy. The proposed control strategy has been tested on a greenhouse of 1 hectare with a lighting system with a nominal power density of 50 Wm−2 requiring an overall power supply of 1 MW for a period of 80 days. The results have been compared with the data coming from another greenhouse of 1 hectare in the same conditions implementing a state-of-the-art strategy for artificial lighting control. Results outlines that potential 19.4% cost savings are achievable. Moreover, the algorithm can be used to transform the greenhouse in a viable source of energy flexibility for grid reliability.

scholarly journals Light Emitting Diodes (LEDs) as Agricultural Lighting: Impact and Its Potential on Improving Physiology, Flowering, and Secondary Metabolites of Crops

2021 ◽  
Vol 13 (4) ◽  
pp. 1985
Author(s):  
Musa Al Murad ◽  
Kaukab Razi ◽  
Byoung Ryong Jeong ◽  
Prakash Muthu Arjuna Samy ◽  
Sowbiya Muneer
Keyword(s):  
Crop Production ◽  
Morphological Changes ◽  
Light Emitting Diode ◽  
Crop Productivity ◽  
Photon Flux ◽  
Flower Initiation ◽  
Nutrient Metabolism ◽  
Light Emitting ◽  
Cultivation Systems ◽  
Lighting Systems

A reduction in crop productivity in cultivable land and challenging environmental factors have directed advancement in indoor cultivation systems, such that the yield parameters are higher in outdoor cultivation systems. In wake of this situation, light emitting diode (LED) lighting has proved to be promising in the field of agricultural lighting. Properties such as energy efficiency, long lifetime, photon flux efficacy and flexibility in application make LEDs better suited for future agricultural lighting systems over traditional lighting systems. Different LED spectrums have varied effects on the morphogenesis and photosynthetic responses in plants. LEDs have a profound effect on plant growth and development and also control key physiological processes such as phototropism, the immigration of chloroplasts, day/night period control and the opening/closing of stomata. Moreover, the synthesis of bioactive compounds and antioxidants on exposure to LED spectrum also provides information on the possible regulation of antioxidative defense genes to protect the cells from oxidative damage. Similarly, LEDs are also seen to escalate the nutrient metabolism in plants and flower initiation, thus improving the quality of the crops as well. However, the complete management of the irradiance and wavelength is the key to maximize the economic efficacy of crop production, quality, and the nutrition potential of plants grown in controlled environments. This review aims to summarize the various advancements made in the area of LED technology in agriculture, focusing on key processes such as morphological changes, photosynthetic activity, nutrient metabolism, antioxidant capacity and flowering in plants. Emphasis is also made on the variation in activities of different LED spectra between different plant species. In addition, research gaps and future perspectives are also discussed of this emerging multidisciplinary field of research and its development.

scholarly journals Increased Plant Quality, Greenhouse Productivity and Energy Efficiency with Broad-Spectrum LED Systems: A Case Study for Thyme (Thymus vulgaris L.)

Plants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 960
Author(s):  
Jenny Manuela Tabbert ◽  
Hartwig Schulz ◽  
Andrea Krähmer
Keyword(s):  
Broad Spectrum ◽  
Energy Savings ◽  
Light Emitting Diode ◽  
Thymus Vulgaris ◽  
Light Spectrum ◽  
Light Emitting ◽  
Biomass Yields ◽  
Lighting Systems

A light-emitting diode (LED) system covering plant-receptive wavebands from ultraviolet to far-red radiation (360 to 760 nm, “white” light spectrum) was investigated for greenhouse productions of Thymus vulgaris L. Biomass yields and amounts of terpenoids were examined, and the lights’ productivity and electrical efficiency were determined. All results were compared to two conventionally used light fixture types (high-pressure sodium lamps (HPS) and fluorescent lights (FL)) under naturally low irradiation conditions during fall and winter in Berlin, Germany. Under LED, development of Thymus vulgaris L. was highly accelerated resulting in distinct fresh yield increases per square meter by 43% and 82.4% compared to HPS and FL, respectively. Dry yields per square meter also increased by 43.1% and 88.6% under LED compared to the HPS and FL lighting systems. While composition of terpenoids remained unaffected, their quantity per gram of leaf dry matter significantly increased under LED and HPS as compared to FL. Further, the power consumption calculations revealed energy savings of 31.3% and 20.1% for LED and FL, respectively, compared to HPS. In conclusion, the implementation of a broad-spectrum LED system has tremendous potential for increasing quantity and quality of Thymus vulgaris L. during naturally insufficient light conditions while significantly reducing energy consumption.

Electrically driven single microribbon based near-infrared exciton-polariton light-emitting diode

CrystEngComm ◽  
2021 ◽  
Author(s):  
Mingming Jiang ◽  
Fupeng Zhang ◽  
Kai Tang ◽  
Peng Wan ◽  
Caixia Kan
Keyword(s):  
High Performance ◽  
Near Infrared ◽  
Light Emitting Diodes ◽  
Light Emitting Diode ◽  
Light Sources ◽  
Coherent Light ◽  
Light Emitting ◽  
Exciton Polaritons ◽  
Laser Devices

Achieving electrically-driven exciton-polaritons has drawn substantial attention toward developing ultralow-threshold coherent light sources, containing polariton laser devices and high-performance light-emitting diodes (LEDs). In this work, we demonstrate an electrically driven...

Reliability of High-Power Light Emitting Diode Attached With Different Thermal Interface Materials

2010 ◽  
Vol 132 (3) ◽  
Author(s):  
Xin Li ◽  
Xu Chen ◽  
Guo-Quan Lu
Keyword(s):  
High Power ◽  
Heat Dissipation ◽  
Light Emitting Diode ◽  
Temperature Cycling ◽  
Fluorescent Light ◽  
Light Sources ◽  
Light Emitting ◽  
Die Attach ◽  
Nanosilver Paste ◽  
Interconnection Material

As a solid electroluminescent source, white light emitting diode (LED) has entered a practical stage and become an alternative to replace incandescent and fluorescent light sources. However, due to the increasing integration and miniaturization of LED chips, heat flux inside the chip is also increasing, which puts the packaging into the position to meet higher requirements of heat dissipation. In this study, a new interconnection material—nanosilver paste is used for the LED chip packaging to pursue a better optical performance, since high thermal conductivity of this material can help improve the efficiency of heat dissipation for the LED chip. The bonding ability of this new die-attach material is evaluated by their bonding strength. Moreover, high-power LED modules connected with nanosilver paste, Sn3Ag0.5Cu solder, and silver epoxy are aged under hygrothermal aging and temperature cycling tests. The performances of these LED modules are tested at different aging time. The results show that LED modules sintered with nanosilver paste have the best performance and stability.

Sign in / Sign up

Export Citation Format

Share Document