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Luminance Normalization of Optical Sheets in a Backlight Unit for LCD-TVs (LCD-TV용 백라이트 광학시트의 휘도 정량화)

  • Jeong, Jong-Mun;Kim, Jung-Hyun;Shin, Myeong-Ju;Lee, Mi-Ran;Chung, Jae-Yoon;Jeong, Hee-Suk;Kim, Jin-Sheon;Hong, Byeong-Hee;Kang, June-Gill;Cho, Guang-Sup
    • Journal of the Korean Vacuum Society
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    • v.16 no.6
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    • pp.424-432
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    • 2007
  • Luminance properties of external electrode fluorescent lamps and optical components in backlight unit (BLU) and optical transmission rates of optical sheets, are investigated for LCD-TV of 32" in diagonal with WXGA level resolution (1366$\times$768). The luminance is measured in 12-lamps and 18-lamps of BLU. The luminance uniformity preserves about 85 % in the 12-lamps backlight, while the luminance of optical components and the efficiency of backlight in the 12-lamps are lower than those in the 18-lamps backlight. When the lamp luminance in BLU having 12-lamps and 18-lamps is normalized as 100 %, the relative luminance of a diffusion plate, a diffusion sheet, a prism sheet (BEF), a polarization sheet (DBEF), has a constant value without dependence on a lamp luminance. The relative luminance of optical components in 12-lamps BLU is lower than that in 18-lamps backlight. The light transmission rate, the relative luminance of liquid crystal display panel with the luminance 100 % of backlight, is 7.14 % in the use of DBEF and BEF, 6.12 % in the use of only DBEF, and 3.21 % in the use of only BEF. Those Data obtained in this experiment for the lamps and optical components, are the design parameters for the LCD backlight.

[Retraction] Effects of Cynanchum wilfordii and Phlomis umbrosa Extracts on Bone Growth and Serum Insulin Like Growth Factor-I ([논문철회] 백하수오와 속단 추출물의 뼈 골격 성장과 IGF-I 생성 촉진 효과)

  • Kang, Yong Koo;Hong, Sang Keun
    • Microbiology and Biotechnology Letters
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    • v.42 no.2
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    • pp.139-144
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    • 2014
  • This study examined the efficacies of Cynanchum wilfordii and Phlomis umbrosa extracts on serum insulin like growth factor-I (IGF-I) and bone growth by raising rats in vivo. C. wilfordii and P. umbrosa extracts significantly increased serum IGF-I by 42% and 22% than the control, respectively. Treatment with ${\alpha}$-amylase when manufacturing these extracts remarkably increased the concentration of IGF-I by 63% and 36% above the control, respectively. This meant that these extracts, especially ${\alpha}$-amylase treated extracts, maintained a higher level of IGF-I secretion in the treated groups. In addition, increases of 6% in femur length were found after 8 weeks of oral administration with these extracts. These results indicate that C. wilfordii and P. umbrosa extracts have beneficial effects on bone growth via IGF-I.

A Case of Granular Cell Tumor of the Breast in a Male Patient (남성유방에서 과립세포종양의 증례 보고)

  • Lee, Gyoung-Eun;Kim, Ji-Young;Kim, Jae Hyung;Jeong, Myeong Ja;Kim, Soung Hee;Kim, Soo Hyun;Kang, Mi-Jin;Lee, Ji Hae;Bae, Kyung-Eun;Kim, Tae Gyu
    • Journal of the Korean Society of Radiology
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    • v.79 no.5
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    • pp.259-263
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    • 2018
  • A 52-year-old male complained of a painless, firm, and slow-growing mass in his right breast outer portion. The chest CT revealed a 3.3 cm-sized oval shaped, microlobulated, mild enhancing mass. Ultrasound showed a microlobulated marginated heterogeneous hypoechoic mass with internal vascularity and calcifications in the mass. On the ultrasound-guided core needle biopsy, the mass was confirmed as a benign granular cell tumor (GCT). The patient transferred to another hospital and underwent surgical removal of the lesion. GCT of the breast is uncommon and mostly benign neoplasm to originate from Schwann cell. Clinical and radiologic features of GCTs, including CT and ultrasound images, mimic malignancy and make diagnosis of GCT more difficult. The CT images of GCTs are much rarely reported. Physicians and radiologists must be aware of radiologic characteristics of this rare benign tumor for male breast, to avoid misdiagnosis this tumor for breast malignancy and overtreat.

Detrital Zircon U-Pb Ages of the Cretaceous Gurye Group, Gurye Basin, Korea: Implications for the Depositional Age and Provenance (백악기 구례분지 구례층군의 쇄설성 저어콘 U-Pb 연대: 퇴적시기와 퇴적물 기원지에 대한 의미)

  • Kim, Youhee;Chae, Yong-Un;Ha, Sujin;Choi, Taejin;Lim, Hyoun Soo
    • Journal of the Korean earth science society
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    • v.43 no.3
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    • pp.405-429
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    • 2022
  • Detrital zircon LA-MC-ICP-MS U-Pb dating of the Cretaceous Gurye Group, Gurye Basin, was carried out. Gurye Group consists of Supyeongri, Geumjeongri, Togeum, and Obongsan formations in ascending order, and five samples were collected for age dating. Based on the dating results, the lowermost Supyeongri and the uppermost Obongsan formations show narrow age ranges. Only Precambrian and Late Cretaceous zircons were found in the Supyeongri and Obongsan formations, respectively. However, the upper and lower Geumjeongri, and Togeum formations show wide age ranges from the Precambrian to Cretaceous. The youngest detrital zircon U-Pb ages of each formation except the Supyeongri Formation, which lacks Cretaceous zircon, were calculated to be ca. 107.4 Ma in the lower Geumjeongri Formation, ca. 104.6 Ma in the upper Geumjeongri Formation, ca. 97.7 Ma in the Togeum Formation, and ca. 88.5 Ma in the Obongsan Formation. Such results indicate that the depositional age of the Gurye Group can be constrained from the Lower Cretaceous Albian to the Upper Cretaceous Coniacian. Based on the distribution of the detrital zircon ages from each formation, the source area of the Gurye Group is interpreted to have been extended from the adjacent Youngnam Massif to the Okcheon Belt throughout the basin evolution. The increase of the Cretaceous zircon with time is thought to reflect the slab roll-back of the proto-Pacific plate during the Cretaceous.

A Study on the Muscovite-Pyrophyllite Mixed Phase in the Shale from the Manhang Formation, Taebaek Area (태백지역 만항층 셰일에서 산출되는 백운모-파이로필라이트 혼합상에 대한 연구)

  • Choi, Seung-Hyun;Mun, Hyang-Ran;Lee, Young-Boo;Lee, Jung-Hoo
    • Journal of the Mineralogical Society of Korea
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    • v.24 no.4
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    • pp.313-320
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    • 2011
  • Mica-type phyllosilicate particles in the shales of the Manhang formation at the Taeback area in the Kangwon Province were studied using electron probe microanalysis (EPMA) and transmission electron microscopy (TEM). The average chemical formula of the mica-type phyllosilicate mineral analysed by EPMA is $K_{1.35}(Fe_{0.18}Mg_{0.03}Al_{3.86})(Si_{6.55}Al_{1.45})O_{20}(OH)_4$. Low K contents compared to the ideal chemistry of muscovite indicate the presence of illite in the mica-type phyllosilicate particle. X-ray diffraction study showed that pyrophyllite commonly coexists with muscovite in the shales from the Manhang Formation. TEM observations showed both the interlayer and intralayer mixing of $9.3-{\AA}$ pyrophyllite and $10-{\AA}$ muscovite layers. The low K content of the mica-type phyllosilicates apparently come from the close mixing of pyrophyllite and muscovite.

Antioxidative ability of ethanol extract from the leaves of Leucaena leucocephala (Lam.) de Wit (백연수(Leucaena leucocephala (Lam.) de Wit) 잎 에탄올 추출물의 항산화능)

  • Kim, Dong Chung;In, Man-Jin
    • Journal of Applied Biological Chemistry
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    • v.60 no.2
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    • pp.185-190
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    • 2017
  • Antioxidative ability of 50% ethanol extract from leaves of Leucaena leucocephala (Lam.) de Wit was investigated. The extraction yield, total polyphenols and total flavonoids of the ethanol extract were $18.3{\pm}0.40%$, $121.3{\pm}11.04{\mu}g$ gallic acid equivalents/mg and $105.2{\pm}2.77{\mu}g$ quercetin equivalents/mg, respectively. The ethanol extract possessed the antioxidative activities such as free radical, cation radical, and nitrite scavenging activities as well as reducing power and lipid peroxidation inhibitory activity. These antioxidative activities of the ethanol extract increased in proportion to the extract concentration. $EC_{50}$ values for free radical scavenging, cation radical scavenging nitrite scavenging, and reducing power were $133.51{\mu}g/mL$, $667.22{\mu}g/mL$, 2.58 mg/mL, and $250.00{\mu}g/mL$, respectively. Polyphenols and flavonoids are suggested to be the key contributors for the antioxidative ability of the ethanol extract from Leucaena leucocephala leaves.

Revisiting Effects of Endorsers' Race on Attitudes Toward Ad and Brand (광고 모델의 인종이 광고와 브랜드 태도형성에 미치는 영향에 대한 고찰)

  • Lee, Eunsun;Kim, Yeo Jung;Ahn, Jungsun
    • The Journal of the Korea Contents Association
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    • v.14 no.8
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    • pp.110-121
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    • 2014
  • As the Korean market is becoming increasingly diverse, it is imperative that marketers targeting the Korean market understand the consumers with various racial and cultural backgrounds. The current study investigated the effects of the endorser race (White vs. Black) on the attitudes toward the ad and brand while varying the experimental context (private vs. public) and product type (high involvement-rational vs. low involvement-emotional) with White participants. Impression management was included as a covariate. The results showed that when the endorser was White and the product was an automobile, participants indicated more positive attitudes toward the ad in the private context than in the public context. When the endorser was Black, the context had no significant effects on the attitudes. The implications of these findings for the Korean market are discussed.

A new species of Potentilla (Rosaceae): P. baekdusanensis M. Kim (양지꽃속(장미과)의 신종: 백두산양지꽃(Potentilla baekdusanensis M. Kim))

  • JO, Hyun;SHIN, Changkeun;SEO, Eunkyoung;KIM, Muyeol
    • Korean Journal of Plant Taxonomy
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    • v.48 no.1
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    • pp.37-42
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    • 2018
  • A new species, Potentilla baekdusanensis M. Kim, is described here. It is found in Baekdusan Mt., Korea. Potentilla baekdusanensis shares several characteristics (pinnately compound leaves, pubescent leaf blades and leaf petioles, different leaflets size, and absent stolons) with the related species P. fragarioides. However, this new species has small plants with short and curved hairs, 7 leaflets, small lower leaflets, a glabrous leaflet margin, and yellow petals with a reddish yellow base. In contrast, P. fragarioides are large plants with long and straight hairs, 9-15 leaflets, large lower leaflets, a ciliate leaf margin, and yellow petals without a reddish yellow base.

Assessment of Water Quality in Paldang-dam Surface Area through the Estimation of Volcanic Ash Toxic Components from Mt. Baekdu (백두산 화산재 유해성분 추정을 통한 팔당댐 유역 수질영향 평가)

  • Jee, Yong Keum;Lee, Gyeng Bin;Choi, Jung Ryel;Kim, Ji Tae
    • Journal of Korea Water Resources Association
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    • v.47 no.3
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    • pp.237-245
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    • 2014
  • Volcanic ash components of Mt. Baekdu were estimated to response the change of water quality environment affected by Mt. Baekdu volcanic ash ejected during eruption. Then the change of water concentrations according to the sedimentation of volcanic ash components were analysed. To estimate volcanic ash components of Mt. Baekdu, similar volcanos were selected through the comparison of main foreign volcano's magma type and the selected volcanic ash components supposed as Baekdu Mountain's. To analyse the change of water concentrations, the change of harmful components affected by volcanic ash sedimentation were analysed and the results were compared with domestic drinking water quality standard. As the result, Al, Cd, F, Fe, Pb, Mg, Cl and Sr could affect to water quality. Among those components, concentrations of Cd, F, Fe, Pb and Mg were estimated to exceed the drinking water quality standard.

Reduced sulfur gas loss in the bag sampling procedure - Comparison by calibration slope values (악취황 성분의 채취와 샘플백 내부의 시료 유실율 비교: 검량선의 기울기를 이용한 평가)

  • Kim, K.H.;Choi, Y.J.;Ahn, J.W.
    • Analytical Science and Technology
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    • v.18 no.4
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    • pp.338-343
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    • 2005
  • In this work, sample loss of reduced sulfur compounds (RSC) was investigated with respect to bag sampling techniques. For comparison purpose, calibration slopes were obtained by analyzing standards prepared by 'within syringe dilution' (WSD) method against those made either by 'Tedlar bag dilution' (TBD) or by 'polyester aluminum bag dilution' (PBD) method. The results indicated that the recovery rate of TBD showed the mean values of about 87%, while those of PBD about 77%. Despite the fact that sample loss is inevitable, precise sampling of reduced sulfur compounds may still be possible, if one acknowledges and be prepared for such loss rates of bag sampling methods.