• Investigative Magnetic Resonance Imaging
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• v.15 no.1
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• pp.22-31
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• 2011

Purpose : To compare free-breathing and respiratory-triggered diffusion-weighted imaging on 1.5-T MR system in the detection of hepatic lesions. Materials and Methods: This single-institution study was approved by our institutional review board. Forty-seven patients (mean 57.9 year; M:F = 25:22) underwent hepatic MR imaging on 1.5-T MR system using both free-breathing and respiratory-triggered diffusion-weighted imaging (DWI) at a single examination. Two radiologists retrospectively reviewed respiratory-triggered and free-breathing sets (B50, B400, B800 diffusion weighted images and ADC map) in random order with a time interval of 2 weeks. Liver SNR and lesion-to-liver CNR of DWI were calculated measuring ROI. Results : Total of 62 lesions (53 benign, 9 malignant) that included 32 cysts, 13 hemangiomas, 7 hepatocellular carcinomas (HCCs), 5 eosinophilic infiltration, 2 metastases, 1 eosinophilic abscess, focal nodular hyperplasia, and pseudolipoma of Glisson's capsule were reviewed by two reviewers. Though not reaching statistical significance, the overall lesion sensitivities were increased in respiratory-triggered DWI [reviewer1: reviewer2, 47/62(75.81%):45/62(72.58%)] than free-breathing DWI [44/62(70.97%):41/62(66.13%)]. Especially for smaller than 1 cm hepatic lesions, sensitivity of respiratory-triggered DWI [24/30(80%):21/30(70%)] was superior to free-breathing DWI [17/30(56.7%):15/30(50%)]. The diagnostic accuracy measuring the area under the ROC curve (Az value) of free-breathing and respiratory-triggered DWI was not statistically different. Liver SNR and lesion-to-liver CNR of respiratory-triggered DWI ($87.6{\pm}41.4$, $41.2{\pm}62.5$) were higher than free-breathing DWI ($38.8:{\pm}13.6$, $24.8{\pm}36.8$) (p value < 0.001, respectively). Conclusion: Respiratory-triggered diffusion-weighted MR imaging seemed to be better than free-breathing diffusion-weighted MR imaging on 1.5-T MR system for the detection of smaller than 1 cm lesions by providing high SNR and CNR.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.8
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• pp.1105-1113
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• 2015

Bokbunja (Rubus coreanus) is a Korean fruit and wild black raspberry that has antioxidant, anticancer, and beauty effects due to its abundant polyphenols and anthocyanins. The purpose of this study was to investigate the blood flow improvement effect of Bokbunja seed oil (BSO) in a high-fat diet-fed mouse model. We examined improvement of blood flow and its related biomarkers in vivo. Mice were divided into four groups; Control, high fat diet control (negative control, HFD), salmon oil control (positive control, HFD+commercial n-3 fatty acid), and BSO experiment groups (HFD+2 g/2,000 kcal, HFD+4 g/2,000 kcal). After the mice were sacrificed, plasma triglyceride, cholesterol, and blood flow-related biomarkers (coagulation factor 7, 12, serotonin, TXB2, PT, and aPTT) were measured in mouse blood and organs. BSO reduced blood viscosity through improvement of blood lipids (cholesterol and plasma triglycerides) as well as levels of blood coagulation factors and blood platelet activity. BSO also delayed blood coagulation time. Thus, we confirmed that BSO inhibits excessive blood clotting of blood vessels and improves blood flow. Taken together, these results suggest that BSO decreases plasma triglycerides and cholesterol and improves blood flow by regulating biomarkers.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.5
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• pp.138-145
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• 1998

Recently, TCS(Traction Control System) is attracting attention, because it maintains traction ability and steerability of vehicles on low-$\mu$ surface roads by controlling the slip rate between tire and road surface. The development of TCS control law is difficult due to the highly nonlinearity and uncertainty involved in TCS. A fuzzy logic approach is appealing for TCS. In this paper, fuzzy logic controller for TCS is introduced and evaluated by the computer simulation with 8 DOF vehicle model. The result indicate that the fuzzy logic TCS improves vehicle's stability and steerability.

• Journal of Korean Electronics
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• v.8 no.1
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• pp.55-59
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• 1988

• Journal of Korean Electronics
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• v.8 no.4
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• pp.67-74
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• 1988

• Journal for History of Mathematics
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• v.8 no.1
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• pp.46-53
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• 1995

• Proceedings of the KHMA Conference
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• 2009.05a
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• pp.3-8
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• 2009

• The Journal of the Korean dental association
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• v.35 no.8 s.339
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• pp.558-564
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• 1997

• The Korean Publising Journal, Monthly
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• s.10
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• pp.8-11
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• 1987

• Journal of the Korean Magnetics Society
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• v.14 no.6
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• pp.236-239
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• 2004

We studied the specular spin valve (SSV) having the spin filter layer (SFL) in contact with the ultrathin free layer composed of Ta3/NiFe2/IrMn7/CoFel/(NOLl)/CoFe2/Cu1.8/CoFe( $t_{F}$)/Cu( $t_{SF}$ )/(NOL2)/Ta3.5 (in nm) by the magnetron sputtering system. For this antiferromagnetic I $r_{22}$M $n_{78}$-pinned spin filter specular spin valve (SFSSV) films, an optimal magnetoresistance (MR) ratio of 11.9% was obtained when both the free layer thickness ( $t_{F}$) and the SFL thickness ( $t_{SF}$ ) were 1.5 nm, and the MR ratio higher than 11% was maintained even when the $t_{F}$ was reduced to 1.0 nm. It was due to increase of specular electron by the nano-oxide layer (NOL) and of current shunting through the SFL. Moreover, the interlayer coupling field ( $H_{int}$) between free layer and pinned layer could be explained by considering the RKKY and magnetostatic coupling. The coercivity of the free layer ( $H_{cf}$ ) was significantly reduced as compared to the traditional spin valve (TSV), and was remained as low as 4 Oe when the $t_{F}$ varied from 1 nm to 4 urn. It was found that the SFL made it possible to reduce the free layer thickness and enhance the MR ratio without degrading the soft magnetic property of the free layer.