• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.925-926
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• 2007

전자계 및 열/유동 해석 프로그램을 활용한 수치해석적 방법으로 변압기 외함의 자계손실과 온도상승을 계산하는 경우, 많은 시간이 소요되기 때문에, 설계 또는 고객 요구시 신속한 대응이 어렵다. 따라서 3차원 간이 계산법을 정립하여 신속 정확한 해석적 방법으로 접근할 필요가 있었다, 본 연구에서는 권선의 누설자속에 의해 발생하는 변압기 외함의 자계손실을 계산하고 이에 따른 온도상승을 추정하고자 하였다. 또한, 실제 변압기의 온도상승 시험을 통해 온도상승 계산 결과의 정확성을 검증하고자 하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.529-530
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• 2006

$Bi_2Sr_2CuO_x$ thin films have been fabricated by atomic layer-by-layer deposition using the ion beam sputtering method. During the deposition, 10 and 90 wt%-ozone/oxygen mixture gas of typical pressure of $1{\sim}9{\times}10^{-5}\;Torr$ are supplied with ultraviolet light irradiation for oxidation. XRD and RHEED investigations reveal out that a buffer layer with some different compositions is formed at the early deposition stage of less than 10 units cell and then Bi-2201 oriented along the c-axis is grown.

• Bulletin of the Korean Chemical Society
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• v.8 no.2
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• pp.73-79
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• 1987

In this work we have investigated temperature dependence of spin-rotational relaxation rate, $(1/T_1)_{SR}$, of methyl carbon-13's in 2-bromo-p-xylene, 2,5-dimethylaniline, and 2,5-dimethylanisole and have found that temperature behaviors of two methyl carbon-13's in ortho- and meta-position, respectively, are substantially different. It has been confirmed that the modified Burke-Chan model proposed by Park et al. can nicely explain different temperature dependence of $(1/T_1)_{SR}$ for these two methyl carbon-13's while the original Burke-Chan model fails to do so.

• Bulletin of the Korean Chemical Society
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• v.11 no.4
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• pp.354-357
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• 1990

Synthesis of dichloro cobalt (Ⅲ) complexes of a flexible $N_2O_2-type$ tetradentate ligand, ethylenediamene-N,N'-di-${\alpha}$-isobutyric acid (eddib), has yielded two geometrical isomers, s-cis-$(Co(eddib)Cl_2)- and uns-cis-(Co(eddib)Cl_2)-.$ A series of substitution reactions, $(Co(eddib)Cl_2)^- {\to} (CO(eddib)Cl H_2O) {\to} (Co(eddib)CO_3)^- {\to} (Co(eddib(H_2O)_2)^+$ have been run for each of the two geometrical isomers. The reaction between the s-cis-(Co(eddib)Cl_2)^-$ complex and L-alanine (L-als) or S-methyl-L-cysteine (L-mcy) gave the meridional s-cis-[Co(eddib)(aa)) (aa = L-ala or L-mcy) complex. The S-methyl-L-cysteine was found to coordinate to cobalt (Ⅲ) ion via the nitrogen and oxygen donor atoms.

• Journal of Chest Surgery
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• v.47 no.2
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• pp.171-173
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• 2014

Saccular aneurysm of the external jugular vein presenting as a neck mass is very rare. We report the surgical treatment of an external jugular venous aneurysm in a 48-year-old female patient due to the cosmetic problem of neck engorgement, concomitant with thyroidectomy for cancer.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.375-380
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• 2008

This study have processed the developing of vane damper with accurate control by using gear which is a flow-control equipment of marine boiler's FD fan on this research. For the developing of vane damper, we have corrected some problem from welding & assembly process by changing the design, and for the case of an emergency case, we have applied the easy disassembly & assembly on that vane damper. Compared to Rink type vane damper in current, we have focused on high efficiency with low price of that new developing damper. For selection of actuator, we have tried to find the propriety with our developing focus. Also, we have developed a jig of assembly processing for high productivity with quality, it caused the best assembly performance with heat-treated & processed parts.

• Korean Journal of Medicinal Crop Science
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• v.21 no.2
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• pp.136-141
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• 2013

Chelidonium majus (CM) contains several isoquinoline alkaloids that have been reported to have various biological activities such as anti-inflammatory, antimicrobial, antioxidant, immune-modulatory, and antitumoral. It has been reported that the extract of CM had an antioxidant potential, however the mechanism has not been verified. In this study, we found that CM extract activated FOXO3a. FOXO3a is a transcription factor that involved in various biological processes such as cell cycle arrest, apoptosis, DNA repair, and ROS detoxification. Transcriptional activities of FOXO3a were regulated by post-translational modifications including phosphorylation, acetylation, and ubiquitination. Protein level of FOXO3a was increased by CM extract. Promoter activities of FOXO-transcriptional target genes such as MnSOD, p27 and GADD45 were activated by CM extract in a dose dependent manner. In addition, protein level of MnSOD, major antioxidant enzyme, was increased by CM extract. Thereby ROS level was decreased by CM in old HEF cells. These results suggest that CM extract has an antioxidant activity through FOXO activation.

• Korean Journal of Clinical Laboratory Science
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• v.43 no.1
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• pp.19-25
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• 2011

The purpose of this study was to analyse brainstem auditory evoked potentials (BAEP) wave change data during microvascular decompression (MVD). The nerve function of Cranial Nerve VIII is at risk during MVD. Intraoperative monitoring of BAEP can be a useful tool to decrease the danger of hearing loss. Between January and December 2009, 242 patients had MVD for hemifacial spasm (HFS) and trigeminal neuralgia (TN). Among intraoperative BAEP changes, amplitude of V-V' was the most frequently observed during cerebellar retraction and decompression step of the MVD procedure. 138 patients (57%) had no BAEP change while 104 patients (42.98%) had BAEP change. 69 patients (28.5%) had Type A-I, 16 patients (6.6%) had Type A-II, 5 patients (2.1%) had Type B, and 13 patients (5.37%) had Type C. MVD is a surgical procedure to relieve the symptoms (e.g. pain, muscle twitching) caused by compression of a nerve by an artery or vein. During BAEP intraoperative monitoring, the surgical step is important in interpreting the changes of wave V. Several potential mechanisms of injury may affect the cochlear nerve, and complete loss of BAEP is often associated with postoperative hearing loss. Intraoperative BAEP monitoring may provide an early warning of hearing disturbance after MVD.

• (The)Study of the Eastern Classic
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• no.34
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• pp.89-112
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• 2009

Park Se-dang who has the pen name of Seogye is a man in the 17th century. Then, Joseon Dynasty is try to restore the state which became impoverished by two wars. When Sung Confucianism of Chu-tz was dogmatized, Seogye analyzed independently the scriptures and was regarded as a traitor against Sung Confucianism. Therefore, this paper discussed the understanding of Seogye's works and its social reflection through the research data about Seogye. Although Seogye has blue blood in his veins, he belonged to a non-mainstream group in the faction of Seo-in and had a liberal inclination. That he has shuned in the school of Sung Confucianism owed to Sabyeunrok of his work, and its main reason is his criticism against Song Si-yeul. He argued the two principles different from Chu-tz's three principles. Also, he not accepted the Chu-tz's theory and was similar to the Wang Yangming school in the issue of gaining knowledge by the study of things Now to conclude, Seogye outstretched the liberal inclination in Sung Confucianism apart from the interpretation of scriptures. He was not indulged in Sung Confucianism of Chu-tz that was gradually ossifying at that time and took his own line. And he devoted himself to the study of practical learning and the education for younger scholars, and had acted as mediator between the Sung Confucianism of Chu-tz and the Practical Science that was in full bloom in the period of King Young-jo and King Jeong-jo.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.84.3-85
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• 2017

Korea Astronomy and Space Science Institute (KASI) has been developing the Camera System for the Total Solar Eclipse (TSE) observation. In 2016 we have assembled a simple camera system consisting of a commercial camera lens, a polarizer, bandpass filters, and a Canon camera to observe the solar corona during the Total Solar Eclipse in Indonesia. For 2017 TSE observation, we have studied and adapted the compact coronagraph design proposed by NASA. The compact coronagraph design dramatically reduces the volume and weight, and used for TSE observation. The camera is used to test and verify key components including function of bandpass filter, polarizer, and CCD during observing the Total Solar Eclipse. In this poster we focus on optical engineering works including designing, analyzing, testing, and building for the TSE observation.