• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.4
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• pp.159-165
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• 2008

The purpose of this paper is to study the impact of concentrated nonlinearities, freeplays, on the aeroelastic behaviors of single- and double-folded control fins. The nonlinearities may cause limit cycle oscillation(LCO) below the linear flutter boundary. The effects of nonlinear hinges on LCO characteristics of the fins are examined as flight condition changes. Nonlinear time-domain flutter analyses are performed, using ZAERO. The results show that the aeroelastic stability boundaries of double-folded fin(DF) are higher than those of the single-folded fin(SF) and the lower hinge freeplay impact more critically on the stability than the upper hinge freeplay of the DF.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05a
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• pp.508-513
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• 1997

One of the moot important constants to be Installed In COLSS, a monitoring system in CE typed reactors, is ROPM which would limit the operating space. This static ROPM was calculated from digital transient analysis assuming that every design basis transient was initiated from the most severe initial condition combination (LCO). Once It could be assured that core condition would not be located at none other than LCO, this static ROPM could be replaced with dynamic ROPM calculated at that condition and the dynamic ROPM would be definitely less than the static ROPM. In order to do, It must be required to calculate the transient discrete sensitivity parameters and parameters change distribution. The purpose of this report is just to propose the enlargement method for thermal margin.

• Proceedings of the Korean Nuclear Society Conference
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• 2003.05a
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• pp.198-198
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• 2003

• Journal of Electrochemical Science and Technology
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• v.11 no.4
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• pp.352-360
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• 2020

Lithium cobalt oxide (LiCoO₂, LCO) has been widely used as a cathode material for Li-ion batteries (LIBs) owing to its excellent electrochemical performance and highly reproducible synthesis even with mass production. To improve the energy density of the LIBs for their deployment in electro-mobility, the full capacity and voltage of the cathode materials need to exploited, especially by operating them at a higher voltage. Herein, we doped LCO with divalent calcium-ion (Ca²⁺) to stabilize its layered structure during the batteries' operation. The Ca-doped LCO was synthesized by two different routes, namely solid-state and co-precipitation methods, which led to different average particle sizes and levels of dopant's homogeneity. Of these two, the solid-state synthesis resulted in smaller particles with a better homogeneity of the dopant, which led to better electrochemical performance, specifically when operated at a high voltage of 4.5 V. Electrochemical simulations based on a single particle model provided theoretical corroboration for the positive effects of the reduced particle size on the higher rate capability.

• Journal of Food Hygiene and Safety
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• v.27 no.3
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• pp.317-324
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• 2012

In order to determine an authenticity of food ingredient, we used DNA barcode method by universal primers. For identification of animal food ingredients, LCO1490/HCO2198 and VF2/FISH R2 designed for amplifying cytochrome c oxidase subunit1 (CO1) region and L14724/H15915 for cytochrome b (cyt b) region on mitochondrial DNA were used. Livestock (cow, pig, goat, sheep, a horse and deer) was amplified by LCO1490/HCO 2198, VF2/FISH R2 and L14724/H15915 primers. Poultry (chicken, duck, turkey and ostrich) was amplified by LCO1490/HCO 2198 and VF2/FISH R2 primers. But, Fishes (walleye pollack, herring, codfish, blue codfish, trout, tuna and rockfish) were only amplified by VF2/FISH R2 primers. For plant food ingredients, 3 types of primers (trnH/psbA, rpoB 1F/4R and rbcL 1F/724R) have been used an intergenic spacer, a RNA polymerase beta subunit and a ribulose bisphosphate carboxylase region on plastid, respectively. Garlic, onion, radish, green tea and spinach were amplified by trnH/psbA, rpoB 1F/4R and rbcL 1F/724R. The PCR product sizes were same by rpoB 1F/4R and rbcL 1F/724R but, the PCR product size using trnH/psbA primer was different with others for plants each. We established PCR condition and universal primer selection for 17 item's raw materials for foods and determine base sequences aim to PCR products in this study. This study can apply to determine an authenticity of foods through making an comparison between databases and base sequences in gene bank. Therefore, DNA barcode method using universal primers can be a useful for species identification techniques not only raw materials but also processed foods that are difficult to analyze by chemical analysis.

• Korean Chemical Engineering Research
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• v.46 no.3
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• pp.555-560
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• 2008

Extraction was performed to prepare ash-free coal from low rank coal under the temperature of $200-430^{\circ}C$ and initial pressure of 0.1MPa. Three kinds of coal samples with different rank were used and N-methyl-2-pyrrolidinone(NMP, polar), 1-methyl naphthalene(I-MN, non-polar), Light Cycle Oil(LCO, non-polar) were used as solvents. Results showed that higher extraction yield could be obtained with NMP than with 1-MN and LCO, but the ash concentration shows minimun in the case of 1-MN. Three operation modes were compared, that is, idle, agitation and ultrasonic extraction mode. From the results, it was found that the extraction yield and ash concentration were 70.09% and 1.03% under the agitation mode, 80.7% and 0.76% under the ultrasonic operation mode respectively in the case of NMP used at the temperature of $350^{\circ}C$. Similar results were obtained with 1-MN. Effect of ultrasonic on the extraction was estimated as 15-20% increase in the yields and 26% reduction in the ash concentration.

• Journal of Life Science
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• v.18 no.7
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• pp.1015-1018
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• 2008

To analyze the population genetic structure of the oyster Crassostrea gigas Thunberg, 34 specimens werecollected from Gamak bay in March, 2007. Total genomic DNA was extracted from each sample and PCR was performed to identify haplotypes of oyster by using HCO2918 and LCO1491 primers. Four kinds of haplotypes (CR1, CR2, CR3, and CR4) were identified. Among these group, CR3 showed the highest relative frequency at 73% than any other of haplotypes. On the basis of hierarchical genetic structure, the population of Gamak showed a higher genetic relationship with Namhae, but the genetic distance between southern and western coasts was negative and no statistical significance was found (p>0.05). Consequently, the oyster from Korea coast is determined to be both homogenous and large.

• Tuberculosis and Respiratory Diseases
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• v.46 no.4
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• pp.489-499
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• 1999

Background: The patient with bronchiectasis may have obstructive ventilatory impairment combined with mild restrictive ventilatory impairment due to fibrosis of surrounding lung parenchyme and pleural adhesions caused by chronic recurrent pulmonary infections. Since hyperinflation or emphysematous change can be occured in bronchiectasis, pulmonary functions such as lung volumes and diffusing capacity may also vary with associated emphysema. Methods: For the evaluation of lung volumes and diffusing capacity in bronchiectasis with respect to the anatomic types and severity of bronchiectasis, a total of 40 cases comprising 24 cases of tubular, and 16 cystic type of bronchiectasis were analyzed retrospectively. Correlation between lung functions and extent of bronchiectasis or associated emphysema detected in HRCT were also evaluated. Results: Vital capacity(VC) tended to decrease in cystic type than in tubular type. As the severity of bronchiectasis became serious, the VC were significantly reduced, whereas the total lung capacity(TLC), residual volume(RV) and its ratio to the total lung capacity(RV/TLC) had no significant difference. Lung clearance index(LCI) was significantly increased in cystic type than in tubular type, whereas the slope of phase III in single breath nitrogen curve($\triangle$N2/L) was not significantly changed regard to the type and severity of bronchiectasis. DLCO and DLCO/VA reflecting diffusing capacity were significantly decreased in cystic type and also as the severity of bronchiectasis became serious. The correlation coefficient of VC, DLCO and LCI with the extent of bronchiectasis were -0.322, -0.339 and 0.487, respectively, whereas other parameters were not significantly correlated with the extent of bronchiectasis. VC and DLCO correlated negatively with the extent of emphysema while RV, RV/TLC, LCI and $\triangle$N2/L correlated positively. Conclusion: These findings suggest that the reduction of VC and diffusing capacity or uneven distribution of inspired gas in bronchiectasis are related to both the extent of bronchiectasis and associated emphysema while increased residual volume be related to the extent of associated emphysema alone.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1880-1883
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• 1997

An Parallax-Barrier type autostereoscopic display system is implemented to overcome the handicap of current glass-typed stereo imaging system which gives operators unnatural feeling and reluctance. This system is composed of image mixing part of two input images, A/D transformation part, scan conversion part to eliminate the rainbow interference phenomenon, and pin-hole type barrier lens. For the fine display the accurate slit width of barrier is calculated in consideration of retina size, and the samsung 10.4" TFT-LCO was used as flat display monitor.itor.

• Information and Communications Magazine
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• v.31 no.2
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• pp.21-28
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• 2014

본고에서 디지털 홀로그래피를 위한 SLM중 대표적인 몇 가지 기술에 대한 동향을 살펴보았다. 먼저 SLM픽셀 피치에 따른 홀로그램 영상의 특성에 대해 논의하고, 픽셀화된 SLM으로써 현재 상용화 되고 있는 DMD SLM 과 LCoS SLM의 특성에 대해 살펴 보았다. 픽셀화 되지 않은 SLM 인 음향 광학 변조기와 OASLM 에 대해서도 살펴 보았다. 양질의 디지털 홀로그래피를 구현하기 위하여 궁극적으로 필요한 픽셀 피치 1 ${\mu}m$ 이하 SLM 의 개발 현황과 복소 변조 SLM 에 대해서도 알아보았다.