• Journal of the Institute of Electronics Engineers of Korea TE
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• v.39 no.2
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• pp.6-10
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• 2002

Al films (1000~4000${\AA}$)were deposited on glass and polymer(polyethersulfine) plastic substrates by DC-magnetron sputtering for plastic-based flat-panel displays. A stepped heating process was used both to improve the electrical characteristics and to diminish the thermal expansion of the polymer substrates. Following this procedure, we could succeed in sputtering Al films without any cracking or shrinkage of the polymer substrates. The treatment temperatures and deposited process of Al films were under 200$^{\circ}C$. Also, this low temperature fabrication process allows the application of plastic substrates. Scanning Electrom Microscopy, Atomic Force Microscopy, X-ray Dffractometry, and electrical measurements such as resistivity measurements were performed to investigate the properties of deposited the Al films and their reliability. 

• Publications of The Korean Astronomical Society
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• v.27 no.3
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• pp.71-80
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• 2012

We have developed superconducting mixer receivers for 129 GHz VLBI observation in Korean VLBI Network (KVN). The developed mixer has a radial waveguide probe with simple transmission line L-C transformer as a tuning circuit to its 5 series-connected junctions, which can have 125 - 165 GHz as the operation radio frequency (RF). For intermediate frequency (IF) signal path a high impedance quarter-wavelength line connects the probe to one end of symmetric RF chokes. The double side band (DSB) receiver noise of the mixer was about 40 K over 4 - 6 GHz IF band, whereas we achieved the uncorrected single side band (SSB) noise temperature of about 70 K and better than 10 dB image rejection ratio in 2SB configuration with 8 - 10 GHz IF band. Insert-type receiver cartridges employing the mixers have been under commission for KVN stations.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.28.2-28.2
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• 2009

군사적, 산업적 용도로 널리 활용되고 있는 적외선 검출기는 InSb, HgCdTe(MCT)와 같은 물질들을 감지 소자로 사용하고 있다. 현재 가장 많이 사용되는 MCT는 적외선의 전 영역을 감지할 수 있는 장점이 있지만, 대면적 제작이 어려운 단점이 있다. 이에 비해 InSb는 안정적인 재료의 특성, 높은 전하이동도($1.2\times10^6\;cm^2/Vs$) 그리고 대면적 소자 제작의 가능성 등이 높게 평가되어 차세대 적외선 검출소자로 각광 받고 있다. InSb 적외선 수광 소자는 1970년대부터 미국을 중심으로 이온주입, MOCVD 또는 MBE와 같은 다양한 공정을 이용하여 제작되어 왔으며, 앞으로도 군수용 제품을 비롯하여 산업전반에서 더욱 각광을 받을 것으로 예상된다. 하지만 InSb는 77 K에서 0.225 eV의 상대적으로 작은 밴드갭을 갖고 있기 때문에 누설전류로 인한 성능저하가 고질적인 문제로 대두되었고, 이를 해결하기 위한 고품질 절연막 연구가 InSb 적외선 수광 소자 연구의 주요 이슈 중 하나가 되어왔다. PECVD, photo-CVD, anodic oxidation 등의 공정을 이용하여 $SiO_2$, $Si_3N_4$, 양극산화막(anodic oxide) 등 다양한 물질들에 대한 연구가 진행되었고[1,2], 산화막과 반도체 계면에서의 열확산을 억제하여 계면트랩밀도를 최소화하기 위한 연구도 활발히 이루어졌다[3]. 하지만 InSb 소자의 성능개선을 위한 최적화된 산화막에 대한 연구는 여전히 불충분한 실정이다. 본 연구에서는 n형 (100) InSb 기판 (n = 0.2 ~ $0.85\times10^{15}cm^{-3}$ @ 77 K)을 이용하여 양극산화막, $SiO_2$, $Si_3N_4$ 등을 증착하고 절연막으로서 이들의 특성을 비교 분석하였다. 양극산화막은 상온에서 1 N KOH 용액을 이용하여 양극산화법으로 증착하였으며, $SiO_2$, $Si_3N_4$는 PECVD로 $150^{\circ}C$에서 $300^{\circ}C$까지 온도를 변화시켜가며 증착하였다. SEM분석과 XPS분석으로 두께의 균일도와 절연막의 조성, 계면확산 정도를 확인하였으며, I-V와 C-V 커브측정을 통해 각 절연막의 전기적 특성을 평가하였다. 이 분석들을 통해 각각의 공정 조건에 따른 절연막의 상태를 전기적 특성과 관련지어 설명할 수 있었다.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.2
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• pp.136-141
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• 2005

The capability of utilizing a TCA cycle intermediates as the sole carbon source by the multi-vitamin auxotrophic yeast Torulopsis glabrata CCTCC M202019 was demonstrated with plate count method. It is indicated that T. glabrata could grew on a medium with one of the TCA cycle intermediates as the sole carbon source, but more colonies were observed when glucose, acetate and one of the TCA cycle intermediates coexisted in the medium. Among the intermediates of the TCA cycle examined in this study, cell growth was improved by supplementing oxaloacetate. Further investigation showed that the presence of acetate was necessary when oxaloacetate was supplemented. By supplementing with 10 g/L of oxaloacetate in pyruvate batch fermentation, dry cell weight increased from 11.8 g/L to 13.6 g/L, and pyruvate productivity was enhanced from $0.96\;gL^{-1}h^{-1}\;to\;1.19 gL^{-1}h^{-1}$ after cultivation of 56 h. The yield of pyruvate to glucose was also improved from 0.63 g/g to 0.66 g/g. These results indicate that under vitamins limitation, the productivity and yield of pyruvate could be enhanced via an increase of cell growth by the supplementation of oxaloacetate.

• Textile Coloration and Finishing
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• v.6 no.1
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• pp.33-43
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• 1994

In the present work, to clarify the mechanism of the neutral salt effect on the alkaline hydrolysis of PET, many salts with different cations like LiCl, NaCl, KCl, CsCl were added to the aqueous alkaline solutions. Then PET was hydrolyzed with aqueous solutions of many salts in alkali metal hydroxides under various conditions. Some conclusions obtained from the experimental results were summarized as follows. The reaction rate of the alkaline hydrolysis of PET was increased by the addition of neutral salts and In k was increased nearly linearly with the square root of ionic strength of reaction medium. This fact suggested that the ionic strength effect by Debye-Huckel and Bronsted theory was exerted on the reaction. The specific salt effect was also observed. The reaction rate was increased with the increase in the electrophilicity of cations of neutral salts, i. e., in the order of $Cs^+$/ < $K^+$/ $a^+$/ $i^$^+$. It was considered that the reaction rate was increased in the order of C $s^+$. < $K^+$. $a^+$. $i^+$. because the lowering effect of the cations on the negative charge of PET surface was increased with the electrophilicity of cations. It was thought that $E_{a}$ was increased because the cations of neutral salts decreased the negative charge of PET surface. It, however, was inferred from the increase in ${\Delta}$S＊ and the decrease in the ${\Delta}$G＊ that the cations of neutral salts associated with PET increased the collision frequency between carbonyl carbon and OH- ion and then accelerated the reaction rate.te.

• Korean Journal of Acupuncture
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• v.37 no.3
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• pp.203-208
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• 2020

Objectives : Since there are complex associations between diseases/symptoms and acupoints, one-to-one correspondence may not be the proper approach. Pattern identification has been being used as a clinical framework to make treatment decisions by extracting and synthesizing clinical data including patients' signs and symptoms. In this article, we propose two different models explaining the relationships between diseases and acupoints based on the branch treatment [Zhibiaofa] and the root treatment [Zhibenfa]. Methods : We explained the relationships between diseases/symptoms and acupoints from the example data from our previous study on traditional acupuncture point selection patterns for pain control. Diseases include low back pain, migraine, irritable bowel syndrome, osteoarthritis, ankle sprain, carpal tunnel syndrome, and dysmenorrhea, and acupoints included LI4, BL23, BL25, SP6, BL60, TE5, and CV4. Results : The relationships between diseases/symptoms and acupoints can be explained directly based on the branch treatment, and also can be explained indirectly through pattern identification based on the root treatment. Pattern identifications included both meridian-based pattern identification based on the spatial information of diseases and visceral organ-based pattern identification based on the characteristics of diseases. Conclusions : In the East Asian traditional medicine, Korean medicine doctors choose the most appropriate acupoints based either on the diseases/symptoms (i.e., branch treatment) or on the results of pattern identifications (i.e., root treatment). It is necessary to understand the two different approaches to choose specific acupoints for the targeted diseases.

• Journal of Nutrition and Health
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• v.32 no.8
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• pp.877-886
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• 1999

To assess the effect of an antenatal nutritional status on pregnancy outcome, especially neonatal birty weight, one-day 24hr-recall and two-day recording methods for dietary survey and interview for general and obstetric characteristics of each subject were completed and pregnancy outcome was recorded by phone after delivery. 147 pregnant women attending routinely public health centers in Ulsan were divided into 1st trimester(n=36), 2nd trimester(n=102), 3rd trimester(n=71) by LMP(Last Menstrual Period) because some subjects attended repeatedly in different trimester. The subjects were aged 27.9$\pm$2.9 as mean and the level of education was senior high school and more. 20.4% of subjects experienced spontaneous abortion and 30.0% experienced induced abortion in previous pregnancy. Mean intakes of all nutrients except ascorbic acid were significantly different but dietary composition of energy intakes was not different between trimester. Mineral of calcium, iron and zinc did not meet the RDA for pregnancy outcome was about 20%, which consists of spontaneous abortion (3.4%), caesarian section(15.6%), premature delivery(0.7%) and still births(0.7%). The mean birth weight of neonates is 3.31kg the rate of neonatal birth weight below 10th percentile was 8.4% and the rate of low birth weight(<2.5kg) was 3.1%. By analysis of nutrient factors that influence on the neonatal birth weight (NBW), iron intake correlated negatively and zinc intake correlated positively with NBW in 1st trimester but fat and iron intakes correlated with NBW positively in 3rd trimester. Prepregnancy weight, gestational age at delivery and No. of induced abortion had a positive effects on NBW and No. of spontaneous abortion and te severity of morning sickness had a negative effects on NBW.

• Earthquakes and Structures
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• v.13 no.2
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• pp.165-176
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• 2017

Multi-Axial Testing System (MATS) is a 6-DOF loading system located at National Center for Research on Earthquake Engineering (NCREE) in Taiwan for advanced seismic testing of structural components or sub-assemblages. MATS was designed and constructed for a large variety of structural testing, especially for the specimens that require to be subjected to vertical and longitudinal loading simultaneously, such as reinforced concrete columns and lead rubber bearings. Functionally, MATS consists of a high strength self-reacting frame, a rigid platen, and a large number of servo-hydraulic actuators. The high strength self-reacting frame is composed of two post-tensioned A-shape reinforced concrete frames interconnected by a steel-and-concrete composite cross beam and a reinforced concrete reacting base. The specimen can be anchored between the top cross beam and the bottom rigid platen within a 5-meter high and 3.25-meter wide clear space. In addition to the longitudinal horizontal actuators that can be installed for various configurations, a total number of 13 servo-hydraulic actuators are connected to the rigid platen. Degree-of-freedom control of the rigid platen can be achieved by driving these actuators commanded by a digital controller. The specification and information of MATS in detail are described in this paper, providing the users with a technical point of view on the design, application, and limitation of MATS. Finally, future potential application employing advanced experimental technology is also presented in this paper.

• Journal of Pharmacopuncture
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• v.22 no.1
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• pp.41-48
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• 2019

Objective: The aim of the study was to evaluate the hepatoprotective activity of the bark extract (Ethanol: Water) in the ratio of (3:1) of Rhizophora mucronata (BERM) by intoxicating the $HepG_2$ cell lines with different toxicants viz, $CCL_4$, Ethanol and Paracetamol with different concentrations of the extract were used. The $HepG_2$ cell lines were subjected to MTT Assay for studying the cytotoxicity. Methods: $HepG_2$ cells were plated using 96 well plate in 10% bovine serum, exposed to different toxicants viz, 2% $CCl_4$, 60% Ethanol and 14 mM Paracetamol respectively. The various test concentrations (18.85, 37.5, 75, 150 and $300{\mu}g/ml$) of bark extract of Rhizophora mucronata was added and incubated for 24 hours. Medium was removed after incubation period and 0.5 mg/ml MTT(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) was added and again incubated for 4 hours at 37oC. Then MTT was removed the crystals was dissolved in DMSO and absorbance was measured at 570 nm. Results: The result showed that dose dependent increase in percentage of viability at the doses of 18.85, 37.5, 75, 150, $300{\mu}g/ml$. Te results for the $CCl_4$ intoxicated, at $300{\mu}g/ml$ of the concentration of the extract, the % of viable cells was found out to be 99.6%, for Ethanol intoxicated, 97.67%, and Paracetamol induced, 75.37%, IC50 was $21.53{\mu}g/ml$, $12.61{\mu}g/ml$ and $21.42{\mu}g/ml$ respectively. Conclusion: Thus, we conclude that, the extract possesses defensive effect against different toxicants and can be used as an alternate drug for hepatotoxicity.

• Journal of radiological science and technology
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• v.42 no.2
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• pp.113-117
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• 2019

The purpose of this study was to investigate the FA value which can produce the best T2-weighted images by measuring the signal intensity and noise according to the FA value change in the brain image and the abdominal image of the mouse using micro-MRI. Brain imaging and abdominal imaging of BALB / C mice weighing 20g were performed using 4.7T (Bruker BioSpin MRI GmbH) micro-MRI equipment, Turbo RARE-T2 (spin echo-T2) images were scanned at TR 3500 msec and TE 36 msec. The changes of the FA values were $60^{\circ}$, $80^{\circ}$, $100^{\circ}$, $120^{\circ}$, $140^{\circ}$, $160^{\circ}$ and $180^{\circ}$. We measured signal intensity according to FA values of ventricle and thalamus in brain imaging, The signal intensity of kidney and muscle around the kidney was measured in abdominal images. To obtain SNR and CNR, we measured the background signals of two different parts, not the tissue. In the brain (thalamus) image, the signal intensity of FA $100^{\circ}$ was 7,433 and SNR (6.49) was the highest. In the abdominal (kidney) image, the signal intensity was highest at 16,523 when FA was $120^{\circ}$, and the highest SNR was 8.54 when FA was $140^{\circ}$. The CNR value of the brain image was 1.38 at FA $60^{\circ}$ and gradually increased to 8.29 at FA $180^{\circ}$. The CNR value of the muscle adjacent to the kidney gradually increased from 2.36 when the FA value was $60^{\circ}$ and the highest value was 4,57 at the FA value $180^{\circ}$.