• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.1
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• pp.25-37
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• 1993

This paper describes the use of the J-integral, a one parameter of the non-linear fracture mechanics(NLFM), as a means to measure toughness of steel fiber reinforced concrete. This parameter can be conveniently evaluated from experimentally determined load-deflection curves from flexural tests when a maximum-load failure criterion is employed. And, for high strength concrete which was reinforced steel fiber, with two different fiber length in the form of notched beams, were tested under 3-point bending, and $J_{IC}$, as well as the linear elastic fracture mechanics(LEFM) parameters $K_{IC}$ and $G_{IC}$ were evaluated. The results suggest that $J_{IC}$ is a promising fracture criterion for all of these. while $K_{IC}$(or $G_{IC}$) almost certainly are not. Also it was found that a fiber addition of less than 0.5% did not improve the fracture toughness of the high strength concrete. However, at more than 1.0% in fiber contents, $J_{IC}$ showed significant increases. reflecting the changed character of the concrete; $K_{IC}$ and $G_{IC}$ did not.

• Natural Product Sciences
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• v.12 no.4
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• pp.221-225
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• 2006

Phytochemical examination of the fruits of Actinidia arguta has led to the isolation three organic acids, one coumarin, and three flavonoids. Structures of these compounds were elucidated as protocatechuic acid (1), caffeic acid (2), $caffeoyl-\beta-D-glucopyranoside$ (3), esculetin (4), quercetin (5), quercetin $3-O-\beta-D-galactopyranoside$ (6), and quercetin $3-O-\alpha-L-rhamnopyranosyl$ $(1\rightarrow6)-O-\beta-D-glucopyranoside$ (7) by comparisons with previously reported spectral data. To investigate the anti-inflammatory and anti-oxidative effects of these compounds, nitric oxide production inhibitory activity in LPS-stimulated RAW 264.7 cells and DPPH radical scavenging activities were examined. Nitric oxide productions were reduced significantly by the addition of compounds $[1(IC_{50}=59.27{\mu}g/ml),\;2(IC_{50}=27.95{\mu}g/ml),\;3(IC_{50}=73.09{\mu}g/ml),\;4(IC_{50}=67.44{\mu}g/ml),\;5(IC_{50}=17.40{\mu}g/ml),\;6(IC_{50}=41.99{\mu}g/ml),\;7(IC_{50}=54.46{\mu}g/ml)]$, and extracts $(IC_{50}=56.21{\mu}g/ml)$ compared with positive control, L-NMMA $(IC_{50}=14.48{\mu}g/ml)$. The phenolic compounds also showed anti-oxidative activities. Especially, Compounds $1(IC_{50}=8.87{\mu}g/ml),\;4(IC_{50}=3.41{\mu}g/ml),\;and\;5(IC_{50}=6.06{\mu}g/ml),\;$, showed potent anti-oxidative activities similar to L-ascorbic acid $(IC_{50}=5.89{\mu}g/ml)$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.9
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• pp.559-564
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• 2016

This study examined the malfunction mode of the HCMOS IC under narrow-band high-power electromagnetic wave. Magnetron is used to a narrow-band electromagnetic source. MFR (malfunction failure rate) was measured to investigate the HCMOS IC. In addition, we measured the resistance between specific pins of ICs, which are exposed and not exposed to the electromagnetic wave, respectively. As a test result of measurement, malfunction mode is shown in three steps. Flicker mode causing a flicker in LED connected to output pin of IC is dominant in more than 7.96 kV/m electric field. Self-reset mode causing a voltage drop to the input and output of IC during electromagnetic wave radiation is dominant in more than 9.1 kV/m electric field. Power-reset mode making a IC remained malfunction after electromagnetic radiation is dominant in more than 20.89 kV/m. As a measurement result of pin-to-pin resistance of IC, the differences between IC exposed to electromagnetic wave and normal IC were minor. However, the five in two hundred IC show a relatively low resistance. This is considered to be the result of the breakdown of pn junction when latch-up in CMOS occurred. Based on the results, the susceptibility of HCMOS IC can be applied to a basic database to IC protection and impact analysis of narrow-band high-power electromagnetic waves.

• The Korean Journal of Applied Statistics
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• v.30 no.5
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• pp.719-731
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• 2017

In September 2010, the Korea government increased the speed limit on the Gyeongbu Expressway (Cheonan IC.-Yangjae IC) from 100 to 110 km per hour. This paper considers ARIMA-Intervention model to analyze the effects of the speed limit change on the incidences of traffic accidents and injuries. In addition, in order to investigate the effects more clearly, we also analyze the difference between the two lines of Cheonan IC-Yangjae IC and Busan IC-Cheonan IC. As a result, we observe that the numbers of accidents and injuries have increased after the speed limit change. The increases are strikingly distinctive in comparison to other lines (Busan IC-Cheonan IC) where there have been no changes in the maximum speed limit.

• Journal of the Korean Wood Science and Technology
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• v.17 no.4
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• pp.70-76
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• 1989

The fracture toughness of two species, Pinus rigida MILL and Pinus koraiensis S. et Z. grown in Korea, was investigated by means of single edge notch beam specimen for the six principal systems of crack propagation in wood. The values of the fracture toughness for the LR and the LT systems ($K_{IC}$LR and $K_{IC}$LT) were found to be similar to each other and about 8 times greater than those for the other systems ($K_{IC}$RL, $K_{IC}$TL and $K_{IC}$TR) in both species. The results indicate that the characteristics of fracture toughness in three principal directions of wood (L, R, T direction) are quite different from those of bending strength for the responsible direction. To predict $K_{IC}$ value based on the variation of specific gravity, the experimental values of $K_{IC}$LT and $K_{IC}$TL were compared to the predicted values by published relationship between $K_{IC}$ and specific gravity. However, there were 10 to 25% differences between the former and the latter.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.519-520
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• 2008

In this paper, we design and implement the monolithic zero crossing detection power factor correction IC using a high voltage 30V BCD process. The ZCD PFC IC is designed for power applications, such as notebook, LCD monitor, etc. It includes power factor correction function and several protection circuit, regulator, high-voltage high current output drivers. And also, the designed IC has restart timer function which the output pulse is generated if the output signal of IC is not in a 200us. The simulation results show that the designed IC acts properly as power factor correction IC with efficient protective functions.

• Journal of the Korean Society of Safety
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• v.6 no.4
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• pp.73-80
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• 1991

Interest in fracture of structure has increased significantly over the past decade. New approaches to analyze structural performance have been accompanied by the development of test methods to characterize material behavior in a manner compatible with the analysis. Several test methods have been developed as a results of advances in fracture mechanics, for example, $K_{IC}$ , $J_{IC}$, R-curve tearing instability and CTOD approaches. Among the rest, fracture toughness $K_{IC}$ and $J_{IC}$ can be used as an effective design criterion in fracture mechanics. Generally, the determintion of $J_{IC}$ was performed according to ASTM E 813 or JSME S 001 and $K_{IC}$ was performed according to ASTM E 399. In this study, the test method for $K_{IC}$ and $J_{IC}$ were discussed.scussed.

• Korean Journal of Pharmacognosy
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• v.36 no.3 s.142
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• pp.245-251
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• 2005

Phytochemical examination of the barks of Actinidia arguta led to the isolation of five flavonoids. Structures of compounds were elucidated as catechin (1), (-)-epicatechin (2), quercetin (3), $quercetin-3-O-{\beta}-D-glucopyranoside$ (4), $quercetin-3-O-{\beta}-D-galactopyranoside$ (5) by comparison with previously reported spectral evidences. To investigate the anti-oxidative effect and nitric oxide (NO) production inhibitory activity of these compounds, DPPH radical scavenging activity and nitric oxide production inhibitory activity in $IFN-{\gamma}$, LPS stimulated RAW 264.7 cell were examined. The $IC_{50}s$ were determinied as follows : $1\;$IC_{50}=26.61\;{\mu}g/ml$, $2\;IC_{50}=25.30\;{\mu}g/ml$, $3\;IC_{50}=20.41\;{\mu}g/ml$, $4\;IC_{50}=18.23\;{\mu}g/ml$ , $5\;IC_{50}=30.46\;{\mu}g/ml$, $6\;IC_{50}=28.0;{\mu}g/ml$, $7\;IC_{50}=27.24\;{\mu}/ml$. These NO production inhibitory effects were significantly different compared with the positive control, L-NMMA $(IC_{50}=20.77\;{\mu}g/ml)$, respectively. Compound $1\;(IC_{50}=6.19\;{\mu}g/ml)$, $2\;(IC_{50}=8.98\;{\mu}g/ml)$, $3\;(IC_{50}=7.30\;{\mu}g/ml)$ and $4\;(IC_{50}=7.64\;{\mu}g/ml)$ also showed potent antioxidative activities similar level to ascorbic acid $(IC_{50}=9.22\;{\mu}g/ml)$. These results suggest that barks of A. arguta have a potent anti-oxidative and anti-inflammatory activity.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.1
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• pp.131-136
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• 2013

TSV based 3D ICs have been widely developed with new problems at die and IC levels. It is imperative to test at post-bond as well as pre-bond to achieve high reliability and yield. This paper introduces a new testable design technique which not only test microscopic defects at TSV input/output contact at a die but also test interconnect defects at a stacked IC. IEEE 1500 wrapper cells are augmented and through at-speed tests for pre-bond die and post-bond IC, known-good-die and defect free 3D IC can be massively manufactured+.

• The Plant Pathology Journal
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• v.31 no.1
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• pp.12-24
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• 2015

Rice Blast is the most devastating disease causing major yield losses in every year worldwide. It had been proved that using resistant rice varieties would be the most effective way to control this disease. Molecular screening and genetic diversities of major rice blast resistance genes were determined in 192 rice germplasm accessions using simple sequence repeat (SSR) markers. The genetic frequencies of the 10 major rice blast resistance genes varied from 19.79% to 54.69%. Seven accessions IC337593, IC346002, IC346004, IC346813, IC356117, IC356422 and IC383441 had maximum eight blast resistance gene, while FR13B, Hourakani, Kala Rata 1-24, Lemont, Brown Gora, IR87756-20-2-2-3, IC282418, IC356419, PKSLGR-1 and PKSLGR-39 had seven blast resistance genes. Twenty accessions possessed six genes, 36 accessions had five genes, 41 accessions had four genes, 38 accessions had three genes, 26 accessions had two genes, 13 accessions had single R gene and only one accession IC438644 does not possess any one blast resistant gene. Out of 192 accessions only 17 accessions harboured 7 to 8 blast resistance genes.