• Korean Journal of Optics and Photonics
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• v.35 no.5
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• pp.235-240
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• 2024

Since the coronavirus pandemic, research and application of space sterilization effects using UV light sources have been rapidly increasing. In this paper, the space-sterilization effect of UV LED light sources that can be built into indoor environmental systems or lighting devices is quantitatively analyzed through an illumination optical approach. Through this, it is possible to establish a foundation for optimizing the sterilization effect in indoor spaces in the 275±5 nm wavelength range, which is known to have excellent space-sterilization power.

• Korean Journal of Optics and Photonics
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• v.26 no.3
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• pp.139-146
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• 2015

The effects of a dielectric multilayer mirror on the efficiency of organic light-emitting diodes (OLEDs) were investigated by using optical simulation. Adoption of a dielectric mirror consisting of alternating SiN and $SiO_2$ layers narrowed the emission spectrum due to the microcavity effect, and increased the outcoupling efficiency by a few percent. The layer thicknesses of the dielectric mirror were adjusted to change the wavelength of the resonance mode, which may be used to increase the color purity.

• International Journal of Highway Engineering
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• v.16 no.5
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• pp.133-142
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• 2014

PURPOSES : The objective was to develop the advanced method which could not explain each observation's specific characteristic in the present negative binomial method that results in under-estimation of the standard error(t-value inflation) and affects the confidence of whole derived results. METHODS : This study dealt with traffic accidents occurring within interchange segment on highway main line with RPNB(Random Parameter Negative Binomial) method that enables to take account of heterogeneity. RESULTS : As a result, AADT and lighting installation type on the road were revealed to have random parameter and in terms of other geometric variables, all were derived as fixed parameter(same effect on every segment). Also, marginal effects were adapted to analyze the relative effects on traffic accidents. CONCLUSIONS : This study proves that RPNB method which considers each observation's specific characteristics is better fitted to the accident data with geometrics. Thus, it is recommended that RPNB model or other methods which could consider the heterogeneity needs to be adapted in accident analysis.

• Korean Institute of Interior Design Journal
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• v.19 no.5
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• pp.48-55
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• 2010

Marcel Wanders, one of the greatest designers in the world of contemporary design, was born in the Netherlands. His works run the gamut from interior design to furniture design to lighting design, building a unique world of works. He started to gain fame when he presented "Knotted Chair" at Droog Design in 1996, which was made out of aramid ropes and later became his symbol. In 2000, he established "moooi," a world-renowned design label. By giving characteristic qualities, his works are given meaning, and like a fantastical dream, their images are extremely fantastical and stimulating. As can be seen in his character cover, he puts emphasis on the harmony between minimalism and decoration, establishing his own unique design concept. In this thesis, based on Marcel Wander's design philosophy, his overall design characteristics were classified into theatrical effects and storytelling. Expressive elements depaysement, eclectic mixture, and scale modification were derived from theatrical effects and analyzed; for storytelling, object, semantic cues, and dream and fantasy were derived and analyzed. A distinguishing feature of such analysis is his meaning-centric design approach, the principle by which to form long-term relationships with the users by creating user-centric designs that make them find meaning and values in diverse experiences in their daily routine, giving them familiar yet unique experience.

• Journal of the Korean housing association
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• v.24 no.6
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• pp.69-79
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• 2013

The concept of sustainable development to preserve natural environment through economy in resources and energy is gradually distinguished since environmental problems as a series of air pollution and global warming take place now. Building occupies more than 1/3 of energy consumption in the whole world. Energy consumption of buildings caused a quick increase in the amount of energy use by air conditioning, which has a lot of effects on exhaustion of fossil energy as well as an increase in environmental load. Therefore, this research intends to suggest characteristics and direction for the designing of acclimatization's housing through the case study on acclimatization's housing. Acclimatization's housing is designed to reduce building load from the designing stage unlike green home or low-energy apartment. Also, factors which are commonly applied to acclimatization's housing are applied complexly by design strategic factors of Heating, Cooling and Lighting. The applied design factors make effects mutually and complexly. In addition, design strategy showed different priority by designing direction.

• Journal of the Ergonomics Society of Korea
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• v.25 no.4
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• pp.9-22
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• 2006

1/f fluctuation characteristics can be seen in various natural phenomena, such as breezes, streams, candle flames and the luminous patterns of fireflies. It is said that the 1/f fluctuation are comfortable for human beings. And they are introduced into many industrial products, such as an air conditioner, music, lighting, etc. This study focused on verifying the effects of 1/f fluctuation sound on comfort sensibility. Stimulus were divided into three groups(Group 1, 2, 3) by sound generation methodology. Fluctuation patterns of group 1, 2 were given by three types of fluctuation, 1/f0, 1/f1, 1/f2, and its of group 3 were given by two types of pure tone, 1/f1. In order to verify the effects, we measured the physiological responses of the subjects such as EEG(Electroencephalogram), ERP(Event-Related Potential), and these physiological responses were compared with subjective assessments, free answers. Consequently, we found that factor which had an effect on comfort sensibility was cognitive factor(for stimulus) rather than 1/f fluctuation sound pattern.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.5
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• pp.65-70
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• 2015

Lightning is one of hazards affecting the rapid-transit railway system. There are two effects, which are direct lightning surge to electric car line and induced lightning surge. Protection methods for the direct lightning surge are studied with various occasions, however, study of induced lightning surge is insufficient in spite of a large or small effects. In this paper, it is analysed the way that serge voltage is induced to electric car line by lightning strikes. By modeling the propagation process and the coupling phenomenon of electromagnetic wave produced by lightning strikes, it is achieved to make integrative circuit model combined with existing electric car model. The study is conducted into three different waveform of electromagnetic wave produced by lightning; rectangular wave, double exponential distribution wave, triangle wave. It is also simulated that the inducing serge is coupled to electric car line in an arbitrary location. The simulation results in that, when rapidly changing rectangular wave is supplied, maximum power is induced to electric car line.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.6
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• pp.894-902
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• 2022

This study investigated the effects of photoperiod (NL 12L:12D and LL 24L:0D) and body sizes (30 g and 50 g) on parr-smolt transformation, post-smolt growth and blood properties in the off-season parr-smolt stage of Atlantic salmon reared in a recirculating aquaculture system (RAS). Potential off-season salmon smolt were reared in a freshwater RAS for 80 days and then all experimental fish were transferred to seawater. In both LL groups (LL-30 and LL-50), we recorded and increase in specific growth rate and reduction in feed conversion, although there were no significant difference in body size. The values of osmolality, and serum Na⁺, Cl^- and cortisol concentrations in the LL groups were maintained at lower levels than in NL group fish, and LL group fish were observed to recover to the pre-seawater adaptation state more rapidly than those in the NL group. ID chips were inserted in all smolts reared in freshwater. These fish were subsequently transferred to full-strength seawater and thereafter individual growth rates were monitored for 120 days. The results indicated that compared with smolt reared under natural photoperiodic condition, 24 h lighting in freshwater contributed to enhancing post-smolt specific growth rate in seawater.

• Journal of Animal Science and Technology
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• v.64 no.3
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• pp.432-442
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• 2022

The purpose of this study was to analyse the effects of light colour on rabbit reproductive performance and the expression of key follicular development genes. Rabbits (n = 1,068, 5 months old, 3.6-4.4 kg live body weight) were divided randomly into four groups, housed individually in wire mesh cages and exposed to red, green, blue, and white light-emitting diode (LED) light (control). The lighting schedule was 16 L : 8 D-15 d / 150 lx / 6:00 am-22:00 pm (3 d preartificial insemination to 12 d postartificial insemination). Red light and white light affected the conception rate and kindling rate and increased the total litter size at birth (p < 0.05). The effects of red light on litter size at weaning, litter weight at weaning, and individual weight at weaning increased compared with the green and blue groups. The effects of red light on live litter size at birth were increased compared with those in the blue group (p < 0.05). Compared to white light, green and blue light reduced the number of secondary follicles (p < 0.05). Compared to red light, green and blue light reduced the number of tertiary follicles (p < 0.05). Compared with white light, red LED light resulted in greater ovarian follicle stimulating hormone receptor and luteinizing hormone receptor mRNA expression (p < 0.05). Compared with green and blue LED light, red LED light resulted in greater B-cell lymphom-2 mRNA expression (p < 0.05). Compared with green LED light, red LED light inhibited FOXO1 mRNA expression in rabbit ovaries (p < 0.05). Red light can affect the reproductive performance of female rabbits and the expression of key genes for follicular development.

• Science of Emotion and Sensibility
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• v.21 no.3
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• pp.3-16
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• 2018

Despite the substantial changes made in the product design field to adopt light as an essential design element, there has been little effort to define how customers respond emotionally to the light design of products. Therefore, it is necessary to analyze the emotional effect of light as a new design element. However, previous research focuses solely on deriving optimal lighting conditions to achieve particular emotional effects. Therefore, this paper investigates the customers' desired emotional effects of product's light design. We studied refrigerators that utilize light as the main design element of the product. We applied mixed methods by combining close-ended questions and open-ended question to efficiently derive the desired emotion. Participants were asked to choose the most favorable refrigerator image in each of the twelve image groups and indicate why they choose that image with the short-answer survey form. Approximately one thousand terms were collected, and those terms were classified into 29 groups using thesaurus relationships. The term groups were again classified into the four big emotion categories and labelled as "abstract quality," "light property," "space perception," and "visual comfort." Also, a model of the relationship between desired light style and light properties was proposed, since we observed the light properties related to three other categories. This study used mixed methods to identify the emotional value of a new design element. We suggest that the emotional categories derived and the proposed relationship model could be used to evaluate the product's light design.