• Title/Summary/Keyword: SK

Search Result 2,032, Processing Time 0.028 seconds

Comparison on Cosmetic Activities of Acer mono Bark and Sap (고로쇠 나무의 수피와 수액의 향장활성 비교)

  • Seo, Yong-Chang;Kim, Ji-Seon;Choi, Woon-Yong;Cho, Jeong-Sub;Lim, Hye-Won;Yoon, Chang-Soon;Ma, Choong-Je;Lee, Hyeon-Yong
    • Korean Journal of Medicinal Crop Science
    • /
    • v.19 no.4
    • /
    • pp.264-270
    • /
    • 2011
  • In this study, we investigated the cosmetic application of Acer mono sap through an ultra-high pressure process. Exposing Acer mono sap to a ultra-high pressure process resulted in 90.1% cell viability of human normal fibroblast cells (CCD-986sk) when added at the highest concentration. Acer mono sap also showed the hightest free radical scavenging activity after the ultra high pressure process. The melanogenesis inhibition rate in cloned M-3 cells was 59.0%. Tyrosinase was inhibited at a rate of 87.2% by adding 100% HPAMS. Anti-wrinkle activity was 78.1%. Acer mono sap showed enhanced storage following the ultra high pressure process. These results indicate that Acer mono sap may be a source for functional cosmetic agents capable of improving antioxidant, whitening, and antiwrinkling effects.

NEW PHOTOMETRIC PIPELINE TO EXPLORE TEMPORAL AND SPATIAL VARIABILITY WITH KMTNET DEEP-SOUTH OBSERVATIONS

  • Chang, Seo-Won;Byun, Yong-Ik;Shin, Min-Su;Yi, Hahn;Kim, Myung-Jin;Moon, Hong-Kyu;Choi, Young-Jun;Cha, Sang-Mok;Lee, Yongseok
    • Journal of The Korean Astronomical Society
    • /
    • v.51 no.5
    • /
    • pp.129-142
    • /
    • 2018
  • The DEEP-South (the Deep Ecliptic Patrol of the Southern Sky) photometric census of small Solar System bodies produces massive time-series data of variable, transient or moving objects as a by-product. To fully investigate unexplored variable phenomena, we present an application of multi-aperture photometry and FastBit indexing techniques for faster access to a portion of the DEEP-South year-one data. Our new pipeline is designed to perform automated point source detection, robust high-precision photometry and calibration of non-crowded fields which have overlap with previously surveyed areas. In this paper, we show some examples of catalog-based variability searches to find new variable stars and to recover targeted asteroids. We discover 21 new periodic variables with period ranging between 0.1 and 31 days, including four eclipsing binary systems (detached, over-contact, and ellipsoidal variables), one white dwarf/M dwarf pair candidate, and rotating variable stars. We also recover astrometry (< ${\pm}1-2$ arcsec level accuracy) and photometry of two targeted near-earth asteroids, 2006 DZ169 and 1996 SK, along with the small- (~0.12 mag) and relatively large-amplitude (~0.5 mag) variations of their dominant rotational signals in R-band.

A Tube Thickness Map of Water Wall in a Commercial Circulating Fluidized Bed Combustor (상용 순환 유동층 연소로 수관벽 전열관 두께 지도)

  • Kim, Tae-Woo;Choi, Jeong-Hoo;Shun, Do-Won;Son, Jae-Ek;Jung, Bongjin;Kim, Soo-Sup;Kim, Sang-Done
    • Korean Chemical Engineering Research
    • /
    • v.43 no.3
    • /
    • pp.412-418
    • /
    • 2005
  • The tube thickness map of water wall has been measured in a commercial circulating fluidized bed combustor (200 ton steam/hr, $4.97{\times}9.90{\times}28.98m$ height) with ultrasonic method and tube erosion has been discussed. Severe tube erosion took place in the splash region on all waterwalls including wingwalls. Erosion on the lower part of front and rear walls, close to both side walls, was more serious than other places. Erosion of some tubes around the gas exit was found to be noticible. Tube erosion increased on the wingwall as the position of the tube become closer to the center of the combustor crosssection.

Parallel Feedback Oscillator for Strong Harmonics Suppression and Frequency Doubler (고조파 억압을 위한 병렬 궤환형 발진기와 주파수 체배기)

  • Lee, Kun-Joon;Ko, Jung-Pil;Kim, Young-Sik
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.30 no.2A
    • /
    • pp.122-128
    • /
    • 2005
  • In this paper, a low noise parallel feedback oscillator for harmonic suppression and a frequency doubler are designed and implemented. As the fundamental signal of the oscillator for frequency doubling is extracted between the dielectric resonator (DR) filter and the gate device of the active device, the undesired harmonics at the output of the oscillator is remarkably suppressed. The fundamental signal of the oscillator for frequency doubling directly feeds to the frequency doubler without an additional band pass filter for harmonic suppression. The second harmonic suppression of -47.7 dBc at the oscillator output is achieved, while the fundamental suppression of -37.5 dBc at the doubler output is obtained. The phase noise characteristics are -80.3 dBc/Hz and -93.5 dBc/Hz at the offset frequency of 10 KHz and 100 KHz from the carrier, respectively.

An LED Positioning Method Using Image Sensor of a Smart Device (LED 조명과 스마트 디바이스의 이미지 센서를 이용한 실내 측위 기법)

  • Kim, Jae-Hoon;Kim, Byoung-Sup;Jeon, Hyun-Min;Kang, Suk-Yon
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.40 no.2
    • /
    • pp.390-396
    • /
    • 2015
  • The drastic growth of mobile communication and spreading of smart phone make the significant attention on Location Based Service. The one of most important things for vitalizations of LBS is the accurate estimating position for mobile object. Focusing on an image sensor deployed in smart phone, we develop a LED based positioning estimation framework. The developed approaches can strengthen the advantages of independent indoor applicability of LED. The estimation of LED based positioning is effectively applied to any indoor environment. We put a focus especially on the algorithmic framework. of image processing of smart phone. From LED lighting, we can obtain a typical signal image which contains the unique positioning information. Furthermore test-bed based on smart phone platform is practically developed and all data have been harvested from the actual measurement of test indoor area. This can approve the practical usefulness of proposed framework.

An Analysis of the Distribution Structure and Logistics System of Light Petroleum Products (석유제품의 유통구조와 물류체계 분석 - 경질제품을 대상으로 -)

  • 이희연;최윤선
    • Journal of the Economic Geographical Society of Korea
    • /
    • v.5 no.1
    • /
    • pp.5-24
    • /
    • 2002
  • The purpose of this study is to analyze the distribution structure and the logistics system of light petroleum products from the spatial perspectives. The consumption structure of petroleum products has been changed since the mid 1980s. The growth rate of consumption for light products has been much faster than those of heavy products. The distribution structure of the petroleum products is hierarchically established by refining companies, agencies, and gas stations. The petroleum products agencies are distributed unevenly over the country, and the number of gas stations per one petroleum agency are very differentiated by the region. The light products are directly transported from refining factories to oil storages and then are carried to gas stations. According to the locational characteristics, oil storages which play a key role in the logistics system are categorized into three type. The first type is demand-oriented oil storages which are located near or in the large cities to supply the light petroleum products. The second type is harbors-oriented oil storages which are located within harbors. The third type is railway-oriented oil storages which are located along railway stations. In this study, the thresholds of one oil storage and one gas station are calculated based on the size of supply territory for each oil storage. The average number of population demand that allow a oil storage to stay in business is 1.9 million and average number of cars are 477,200.

  • PDF

Real-Time Simulation of Single and Multiple Scattering of Light (빛의 단일 산란과 다중 산란의 실시간 시뮬레이션 기법)

  • Ki, Hyun-Woo;Lyu, Ji-Hye;Oh, Kyoung-Su
    • Journal of Korea Game Society
    • /
    • v.7 no.2
    • /
    • pp.21-32
    • /
    • 2007
  • It is significant to simulate scattering of light within media for realistic image synthesis; however, this requires costly computation. This paper introduces a practical image-space approximation technique for interactive subsurface scattering. We use a general two-pass approach, which creates transmitted irradiance samples onto shadow maps and computes illumination using the shadow maps. We estimate single scattering efficiently using a method similar to common shadow mapping with adaptive deterministic sampling. A hierarchical technique is applied to evaluate multiple scattering, based on a diffusion theory. We further accelerate rendering speed by tabulating complex functions and utilizing level of detail. We demonstrate that our technique produces high-quality images of animated scenes with blurred shadow at hundreds frames per second on graphics hardware. It can be integrated into existing interactive systems easily.

  • PDF

Anti-Growth Effect of Kaempferol, a Major Component of Polygonati Rhizoma, in Hepatocarcinoma Cells (간암 세포주에서 황정(黃精)의 주요 성분인 Kaempferol의 성장 억제 효과)

  • Joo, Ye-Jin;Jeong, Ji-Cheon
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.26 no.4
    • /
    • pp.519-526
    • /
    • 2012
  • Recently, herbal flavonoids have been implicated for anti-cancer therapy. Flavonoids as a commonly known for their anti-oxidant activity, are contained in the herbal medicine as well as root of plants, vegetables, fruits, grains, tea, and wine. Kaempferol, a component of Polygonati rhizoma, a member of the herbal flavonoids, has been studied for anti-hypercholesterol, anti-hypertension and anti-diabetes. It is also known to be effective in anti-cancer therapy for breast, prostate and other type of cancers. However, the anti-cancer therapeutic mechanisms are pooly understood. Here, we investigated the molecular mechanism underlying kaempferol-induced anti-cancer effects using the human liver cancer cell lines, Hep3B, HepG2, and Sk-Hep-1, and human Chang liver cell as a control. As shown by the FACS analysis, measurement of caspase activity, DAPI and trypan blue staining, and DNA fragmentation assay, kaempferol induced apoptosis in the liver cancer cells with the greater potential in Hep3B cells than other liver cancer cells. In addition, we performed microarray analysis to profile the genome-wide mRNA expression regulated by kaempferol. Many of the apoptosis-related genes were significantly induced in kaempferol-treated Hep3B cells, in particular, the genes associated with MAPK cascade. Additionally, kaempferol induced the mRNA expression of genes involved in MKK7-JNK cascade, MKK3-p38 cascade, and caspase signaling pathway, which are all known to trigger apoptosis. Overall, our data suggest that kaempferol has anti-liver cancer effects by inducing apoptosis through the MKK7-JNK cascade, MKK3-p38 cascade, and caspase signaling pathways.

Analysis of Factors Influencing Oil Tanker Fleet Composition of Domestic Refineries (국내 정유회사의 선대구성에 영향을 미치는 요인의 분석)

  • 백기언;이태우
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
    • /
    • 2003.05a
    • /
    • pp.257-264
    • /
    • 2003
  • The international oil majors have been reducing the size of their own oil tanker fleet since from the beginning of 1980s. Like international oil majors, the Korean refineries are getting more dependent on tanker chartering than tanker ownership for their oil transportation since 1990s. They also prefer spot charter to time charter and this kind of trend continue up to today. Consequently, this paper attempted to find out factors influencing changes in tanker fleet composition. To attain the object, a empirical study is adopted using the ten decision making factors derived from the preceeding study. The findings are that MARPOL and OPA 90, and transportation cost are the most important factors influencing on oil tanker fleet composition.

  • PDF

The Effect of Perceived Justice on Organizational Commitment and Innovative Behavior in a Simplified Personnel System : Focusing on the Roles of Cognitive Attitude and Cognitive Intensity (조직구성원의 직급단계축소에 대한 공정성 지각이 조직몰입과 혁신적 업무행동에 미치는 영향 : 인지태도 및 인지강도의 역할을 중심으로)

  • You, Jong-Ok;Yang, Sung-Byung
    • Journal of Information Technology Services
    • /
    • v.18 no.4
    • /
    • pp.1-22
    • /
    • 2019
  • Companies have attempted to build a rational and future-oriented new personnel system in order to adapt and survive in a rapidly changing environment. Recently, Samsung, LG, SK, and CJ, which are large domestic corporations, have been introducing new types of simplified personnel systems competitively. Although there are several prior studies that tried to classify these simplified personnel systems from a strategic point of view, there is a lack of empirical research in terms of the specific types from the perspective of employees. Therefore, in this study, an empirical study on the simplified personnel system which has currently been highlighted was carried out. The relationship between perceived justice (i.e., distributive justice and procedural justice) and organizational effectiveness (i.e., organizational commitment and innovative behavior) were tested. In addition, the mediating role of cognitive attitude as well as the moderating role of cognitive intensity in the simplified personnel system were investigated. The results of structural equation model using 157 survey data show that both distributive and procedural justice have a positive effect on cognitive attitude toward the simplified personnel system, which in turn leads to increased organizational commitment and innovative behavior. Interestingly, it is found that cognitive intensity intensifies the effect of distributive justice on cognitive attitude, whereas it attenuates the influence of procedural justice as expected. This study is among one of the first empirical studies focusing on the simplified personnel system and expands the concept of related variables such as perceived justice, cognitive attitude, and cognitive intensity in this context. Moreover, by clarifying the causal relationship between perceived justice and organizational effectiveness through the roles of cognitive attitude and cognitive intensity, it could provide several practical implications to managers who are interested in the introduction and early settlement of simplified personnel systems in a successful manner.