• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.27 no.1
• /
• pp.119-131
• /
• 2001

Exposure of the human skin to UV-light can cause sun-tanning, photoaging and even photo-carcinogenesis. Melanin is important in protecting the skin against UV damage, but excessive or uneven melanin production can lead to the formation of freckles and aged spot. Control of hyperpigmentation is becoming even more important as aged population continues to grow. These needs led us to develop effective and safe depigmenting-agent, kojyl 3-aminopropyl phosphate (kojyl-APPA), called Whitegen. The development of whitegen was based on the fact that phosphate group of 3-aminopropyl phosphate can make kojic acid more compatible to the skin membrane and more stable. Instability of kojic acid has been a problem in cosmetic use. The insertion of phosphoester group has been recognized as a powerful tool to improve such physical properties as solubility and stability, because the phosphodiester residue is well characterized as a non-toxic moiety, having a high affinity for cell membranes. Kojyl-APPA showed no tyrosinase inhibition effect compared to kojic acid in vitro, but showed tyrosinase inhibition effect in situ. It means that kojyl-APPA is converted to kojic acid enzymatically in cells. Kojyl-APPA showed the inhibitory activity on melanin synthesis in mouse melanoma and normal humal melnaocytes and also showed long-lasting stability in comparison with its original form (kojic acid). Kojyl-APPA showed depigmenting effects when applied to UVB-induced hyperpigmentated region of guinea pig skin. Based on these results, kojyl 3-aminopropyl phosphate can be used as a safe and effective ingredient for the brightness and cleanness of skin.

• Journal of the Korean Vacuum Society
• /
• v.16 no.5
• /
• pp.338-342
• /
• 2007

The magnesium oxide (MgO) protective layer plays an important role in plasma display panels (PDPs). In this paper, we describe the structural and discharge properties of MgO thin films, which were prepared by the ion-beam-assisted deposition (IBAD) of oxygen as the protective layer of PDPs. The energy of the oxygen ion beam was used as the parameter to control the deposition. We found that the oxygen ion beam energy was effective in determining in structural and discharge characteristics. The lowest firing inception voltage, the highest brightness and the highest luminous efficiency were obtained when the MgO thin film was deposited with an oxygen ion beam energy of 300 eV. The crystallization of the MgO thin film was also measured by X-ray diffraction analysis, and the surface quality was measured by atomic force microscopy.

• Journal of the Korean Society of Food Culture
• /
• v.28 no.4
• /
• pp.386-391
• /
• 2013

This study investigated the effects of freeze-dried sweet pumpkin powder on the baking of bread. Freeze-dried sweet pumpkin powder (0, 3, 6, 9, or 12%) was supplemented during the baking process and the bread volume, weight, specific volume, baking loss rate, texture, and sensory characteristics were measured. The results were following. Freeze-dried sweet pumpkin contained 4.88% water, 4.40% protein, and 4.02% ash. The L-values (brightness) of the bread were significantly lower as increasing amounts of sweet pumpkin powder were added (p<0.001). However, higher values for the a-value (redness) and b-value (yellowness) were observed (p<0.01 for both values). The volume and baking loss rate decreased when the sweet pumpkin powder was added. In contrast, the weight significantly increased as sweet pumpkin powder was added (p<0.01) and the intensity of dark brown color increased. The outer side of the bread was balanced overall, but the outer skin of the bread appeared darker as the amount of sweet pumpkin powder increased. The overall acceptability, hardness (p<0.001), elasticity (p<0.01), cohesiveness (p<0.01), gumminess (p<0.01), and brittleness (p<0.001) increased as sweet pumpkin powder increased as well. However, when sweet pumpkin powder was added at 12%, the overall acceptability value was fairly low. Sensory parameters, such as taste (p<0.001), color (p<0.001), and flavor (p<0.05) were observed when sweet pumpkin powder was used at 3% and these results were lower than the control. Overall acceptability (p<0.001) was best when sweet pumpkin powder was used at 9% and the texture was best when sweet pumpkin powder was used at 6%.

• Journal of Aerospace System Engineering
• /
• v.13 no.5
• /
• pp.79-86
• /
• 2019

An anti-collision light of a rotary-wing aircraft is used for the purpose of preventing collision during the operation of an aircraft and is a key component to ensure flight safety. The anti-collision lights of the Korean Utility Helicopter (KUH) consist of upper and lower lights, and the power supply of anti-collision lights mounted on the aircraft. The anti-collision light is designed as a dual structure capable of brightness control and selective lighting. During the operation after delivery of the aircraft, abnormal lighting of anti-collision light occurred. In this paper, a comprehensive review of the aircraft system and component level was conducted to solve these phenomena at first. Then, the causes of anti-collision light anomalies were analyzed and the design changes are presented. The validity of design changes has been verified through the component and aircraft system ground/flight test.

• The Korean Journal of Food And Nutrition
• /
• v.36 no.3
• /
• pp.193-201
• /
• 2023

Prebiotics are known as components of intestinal microbiota that can improve and maintain human health status by stimulating the growth and activity of the intestinal tract as a method of controlling the intestinal environment. In this study, we examined whether 2'-fucosyllactose (FL) could affect intestinal microbial population and bowel activity. Water content and frequency of mouse feces were increased in the 2'-FL treated group at a high concentration (1,000 mg/kg), with brightness of the color enhanced and physical properties diluted. In addition, intestinal microbial analysis showed that harmful bacteria Clostridium and Staphylococcus strains were decreased and beneficial bacteria such as Lactobacillus strains were markedly increased in the group treated with a high concentration of 2'-FL compared to those in the control group. These findings suggest that administration of 2'-FL can maintain healthy bowel activity by reducing harmful bacteria population and improving diluted physical properties.

• Archives of design research
• /
• v.16 no.3
• /
• pp.329-340
• /
• 2003

The purpose of this study is to provide the methods of harmony in color combination of environmental color for apartment in order to improve the image of the urban landscape. For this study, apartment in Iksan City was selected is a sample and twenty two apartments were analyzed. This framework of this study is A. Hard and L. Sivik's color combination model based on Natural Color System. This study examines various theories on environmental color perception and new approaches to color aesthetics, and tries to present perceptual properties that can be applied to environmental color design First, the principle of color harmony feeling in based on nuance and tone. Therefore, to control brightness and chromaticness with are related with nuance is important in color combination. Second, the aesthetic experience in color preception can be defined as a combined effect of similarities and differences of color attributes. Third, color harmony theory is one of the areas that can be benefit a great deal from and interdisciplinary approach, add empirical study such as this can be used as a basis for environmental color design and evaluation.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.37 no.5
• /
• pp.486-493
• /
• 2024

Lighting has been used for a long time as a medium to convey brightness from darkness, and through incandescent lamps and fluorescent lamps, LED light sources have now become the standard in the lighting industry. Recently, the lighting equipment industry has been undergoing rapid digital transformation, starting with smart lighting, and is evolving into smart lighting customized for individuals and spaces through the development of IoT technology, cloud-based services, and data analysis. However, the blue light emitted from digital devices (computers, smartphones, tablets, etc.) or LED lights stimulates the melanopsin in the optic ganglion cells in the retina of the eye, which in turn stimulates the secretion of melatonin through the pineal gland, which regulates the secretion of melatonin. This can reduce sleep quality or disrupt biological rhythms. This interaction between blue light and melatonin has such a significant impact on human sleep patterns and overall health that it is essential to reduce exposure to blue light, especially in the evening. Human-centered lighting refers to lighting that takes into account the effects of light on the physical and mental areas, such as human activity and awakening, improvement of sleep quality, and health management. Many research institutes study the effects in the visible area and the non-visible area. By studying the impact, it is expected to improve the quality of human life. In this study, we plan to study ways to implement human-centered lighting by collecting sunrise and sunset data and linking commercialized LED packages and control devices with open-source hardware.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2017.11a
• /
• pp.206-208
• /
• 2017

In recent years, we have been working on the improvement project of mercury 3-lecture type at the Geummundo lighthouse for more than 100 years. We have installed toxic mercury removal, LED light source, and dualization system for nonstop. It can be seen as an example. Circular restoration of the entire frame is performed, and the real-time status can be grasped through the installation of the double-ball bearing and the remote control system. After installation, optical measurement through Hanvit secured the optical performance of 2,000,000 cd of floating brightness of 300cd, proving the efficient possibility of introducing the domestic rotary type light source using LED light source.

• The Bulletin of The Korean Astronomical Society
• /
• v.42 no.2
• /
• pp.85.1-85.1
• /
• 2017

We develop a coronagraph to measure the coronal electron density, temperature, and speed by observing the linearly polarized brightness of solar corona with 4 different wavelengths. Through the total solar eclipse on 21 August 2017, we test an operating software of a prototype coronagraph working with two sub-systems of two motorized filter wheels and a CCD camera that are controlled by a portable embedded computer. A Core Flight System (CFS) is a reusable software framework and set of reusable software applications which take advantage of a rich heritage of successful space mission of NASA. We use the CFS software framework to develop the operating software that can control the two sub-systems asynchronously in an observation scenario and communicate with a remote computer about commands, housekeeping data through Ethernet. The software works successfully and obtains about 160 images of 12 filter sets (4 bandpass filters and 3 polarization angles) during the total phase of the total solar eclipse. For the future, we can improve the software reliability by testing the software with a sufficient number of test cases using a testing framework COSMOS. The software will be integrated into the coronagraph for balloon-borne experiments in 2019.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.44 no.1
• /
• pp.40-49
• /
• 2007

In a visual driver-assistance system, separating moving objects from fixed objects are an important problem to maintain multiple hypothesis for the state. Color and edge-based tracker can often be 'distracted' causing them to track the wrong object. Many researchers have dealt with this problem by using multiple features, as it is unlikely that all will be distracted at the same time. In this paper, we improve the accuracy and robustness of real-time tracking by combining a color histogram feature with a brightness of Optical Flow-based feature under a Sequential Monte Carlo framework. And it is also excepted from Tracking as time goes on, reducing density by Adaptive Particles Number in case of the fixed object. This new framework makes two main contributions. The one is about the prediction framework which separating moving objects from fixed objects and the other is about measurement framework to get a information from the visual data under a partial occlusion.