• Transactions of Materials Processing
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• v.20 no.1
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• pp.73-78
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• 2011

The flashing reduces the part quality and the productivity of the molding process. We developed a contact pressure sensor to detect the flashing immediately. The performance of the sensor was analyzed in a simple 2D simulation. The sensor was applied to an automotive bumper mold with cavity pressure sensors. It showed sensitive output signal for the mold response by the cavity pressure change. It was confirmed that the flashing at the gate area occurred in the filling stage by the pressure increase due to growth of the melt flow length. The sensor output was correlated with the cavity pressure sensor output.

• Publications of The Korean Astronomical Society
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• v.8 no.1
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• pp.243-263
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• 1993

One hundred forty two digital spectra of 110 standard stars with 1 A resolution in ${\lambda}{\lambda}\;3000\;A\;{\sim}4150\;A$ region were analyzed to determine the spectral indices sensitive to the atmospheric parameters. The standard stars cover the temperature in the range of $T_eff$ from ${\sim}4000^{\circ}$ to ${\sim}7000^{\circ}\;K$ and the surface gravity in the range of log g from 0 to 5 and the metal abundance [Fe/H] from -2.7 to 0.4. We have derived physical parameters, theta(=T/5040), log g, and [Fe/H] for the standard stars using indices, P(38/93), Fe I(A), Fe I(B), SrII, and $H{\delta}$, with overall accuracies of 0.067, 0.617, and 0.466, respectively. However for some region of spectral type and metallicity, those can be obtained with better accuracies. Those indices are found to be useful especially for stellar gravity determination.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.469-470
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• 2006

[ $TiO_2$ ] nanoparticle was synthesized by the flame method, which was controlled by varying the ratio and flow rate of gas mixtures consisting of oxygen (oxidizer), methane (fuel) and nitrogen (carrier gas). The crystalline phases of $TiO_2$ nanoparticle depended strongly on the temperature distribution in the flame, whereas the morphology was not sensitive. We proved that the anatase phase formed without the phase transformation in the flame and the rutile phase generated through several phase transformations.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.211-217
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• 1997

The physical and chemical stability of anthocyanins from a Korean pigmented rice variety was investigated at various conditions of pH, temperature, metal ion, sugar, organic acid and light. The anthocyanin pigments were relatively stable with half-lives of 36 days (pH 2.0) and 17 days (pH 3.0), while they were decomposed in a day at neutral and basic pH of 7.0 and 9.0 at $25^{\circ}C$. The anthocyanins also showed high thermal stability at pH 3.0; the half-lives were 7.4 hr, 23.6 hr and 96.3 hr at $95^{\circ}C,\;75^{\circ}C\;and\;50^{\circ}$, respectively. Addition of di- and tri-valent metal ions at pH 3.0 resulted in the increase of color intensity and stability throughout 21 days of storage periods at $25^{\circ}C$. Most sugars added accelerated the degradation of anthocyanin pigments, so that fructose showed the greatest degradation effect on the pigments. Addition of citric acid at pH 3.0 increased stability of anthocyanins, while tartaric acid decreased stability. The anthocyanins were very sensitive on light irradiation with a degradation half-life of 14 hr under 20,000 lux-light dosage at pH 3.0.

• The Journal of Pediatrics of Korean Medicine
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• v.26 no.4
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• pp.10-23
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• 2012

Objectives: Gagamyanggyeoksan (G-YGS) has been used to suppress allergic reaction, however, the cellular target of G-YGS and its mode of action remain unclear. The present study was designed to investigate the effect of extracted G-YGS on the PMA and lonomycin (PI)-induced activation of RBL-2H3. Methods: For this investigation, We examined IL-4, IL-13 mRNA expression by Real-Time PCR, IL-4, IL-13 production by ELISA analysis and manifestations of GATA-1, GATA-2, NF-AT1, NF-AT2, AP-1 and NF-${\kappa}B$ p65 transcription factors by western blotting, OVA-specific IgE, IL-4, IL-13 by mouse be sensitive to OVA. Results: Here we showed that treatment of RBL-2H3 mast cells with G-YGS, suppressed PI-induced production of Th2 cytokines including IL-4 and IL-13 in a dose dependent manner. The mRNA expression of IL-4 were completely abolished by G-YGS at the concentration of $100{\mu}g/ml$. Data from a stable cell lines consistently expressing IL-4. And the mRNA expression of IL-13 were abolished by G-YGS at the $200{\mu}g/ml$. But there is no difference between the $50{\mu}g/ml$, the $100{\mu}g/ml$ and the comparison. Results from the western blot analysis of transcription factors involving IL-4 and IL-13 expression indicated that it prominently decreased the expression of mast cell specific transcricption factors including GATA-1, GATA-2, NF-AT2, c-Jun, NF-${\kappa}B$ p65 but not c-Fos. And G-YGS suppressed IgE, IL-4, IL-13 in mouse be sensitive to OVA. Conclusions We suggested the anti-allergic activities of G-YGS might be mediated by down-regulation of Th2 cytokines such as IL-4 and IL-13 through the regulation of transcription factors as GATA-1, GATA-2, NF-AT2, c-Jun, NF-${\kappa}B$ p65.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.2
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• pp.161-167
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• 1988

Studies were carried out to examine the effects of simulated acid rain on the various crops of rice, peper, tomato, pumpkin, egg plant, potato, soybean, radish, cucumber, common pea, sweet potato, corn, lettuce, chinse cabbage, spinach, under the condition of the rains of pH 3.0. The rain was adjusted to pH 4.0, 3.0, 2.0 with sulfuric acid, and soybeans were exposed with the various pH levels, eighteen times every other days. The symptoms of damage, ratios of destroyed leaf and sulphur content by leaves were investigated. The results obtained were as follows. 1. The exposure to the rain resulted in the reddish brown or white pigment spots in the leaves surface and the colour was developed red and darker along the edge of spots. 2. Most crops were affected with acid rain of pH 3.0 at which the amount of chlorophyl was decreased. 3. The spinach, chinese cabbage, lettuce were sensitive to the acid rain, however, the peper, tomato pumpkin were resistance to it. 4. The content of chlorophyl was decreased with increasing leave injury. 5. The sulphur content in leave was increased with increasing acidity of the rain, however the yield was decreased.

• Genomics & Informatics
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• v.11 no.4
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• pp.245-253
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• 2013

A radioresistant cell line was established by fractionated ionizing radiation (IR) and assessed by a clonogenic assay, flow cytometry, and Western blot analysis, as well as zymography and a wound healing assay. Microarray was performed to profile global expression and to search for differentially expressed genes (DEGs) in response to IR. H460R cells demonstrated increased cell scattering and acidic vesicular organelles compared with parental cells. Concomitantly, H460R cells showed characteristics of increased migration and matrix metalloproteinase activity. In addition, H460R cells were resistant to IR, exhibiting reduced expression levels of ionizing responsive proteins (p-p53 and ${\gamma}$-H2AX); apoptosis-related molecules, such as cleaved poly(ADP ribose) polymerase; and endoplasmic reticulum stress-related molecules, such as glucose-regulated protein (GRP78) and C/EBP-homologous protein compared with parental cells, whereas the expression of anti-apoptotic X-linked inhibitor of apoptosis protein was increased. Among DEGs, syntrophin beta 2 (SNTB2) significantly increased in H460R cells in response to IR. Knockdown of SNTB2 by siRNA was more sensitive than the control after IR exposure in H460, H460R, and H1299 cells. Our study suggests that H460R cells have differential properties, including cell morphology, potential for metastasis, and resistance to IR, compared with parental cells. In addition, SNTB2 may play an important role in radioresistance. H460R cells could be helpful in in vitro systems for elucidating the molecular mechanisms of and discovering drugs to overcome radioresistance in lung cancer therapy.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2007.06a
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• pp.109-112
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• 2007

In this paper we describe a robust method of improving precision in monitoring high energy ion implantation processes. Ion implant energy accuracy was measured in the device manufacturing process using an unpatterned implanted layer on an intrinsic p-type silicon wafer. To increase Rs sensitivity to energy at the well implant process, a PN junction structure was formed by P-well and deep N-well implants into the p-type Si wafer. It was observed that the depletion layer formed by the PN junction was very sensitive to energy variation of the well implant. Conclusively, it can be recommended to monitor well implant processes using the Rs measurement method described herein, i.e., a PN junction diode structure since it shows excellent Rs sensitivity to variation caused by energy difference at the well implant step.

• International Journal of Oral Biology
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• v.30 no.3
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• pp.85-90
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• 2005

Homeostatic pH is very important for various cellular processes, including metabolism, survival, and death. An imbalanced-pH might induce cellular acidosis, which is involved in many abnormal events such as apoptosis and malignancy. One of several factors contributing to the onset of metabolic acidosis is the production of lactate and protons by lactate dehydrogenase (LDH) in anaerobic glycolysis. LDH is an important enzyme that catalyzes the reversible conversion of pyruvate to lactate. This study sought to examine whether decreases in extracellular pH induce apoptosis of CHO cells, and to elucidate the role of mitogen-activated protein kinases (MAPKs) in acidification-induced apoptosis. To test apoptotic signaling by acidification we used CHO dhfr cells that were sensitive to acidification, and CHO/anti-LDH cells that are resistant to acidification-induced apoptosis and have reduced LDH activity by stable LDH antisense mRNA expression. In the present study, cellular lactic acid-induced acidification and the role of MAPKs signaling in acidification-induced apoptosis were investigated. Acidification, which is caused by $HCO{_3}^-$-free conditions, induced apoptosis and MAPKs (ERK, JNK, and p38) activation. However, MAPKs were slightly activated in acidic conditions in the CHO/anti-LDH cells, indicating that lactic acid-induced acidification induces activation of MAPKs. Treatment with a p38 inhibitor, PD169316, increased acidification-induced apoptosis but apoptosis was not affected by inhibitors for ERK (U0126) or JNK (SP600125). Thus, these data support the hypothesis that activation of the p38 MAPK during acidification-induced apoptosis contributes to cell survival.

• Earthquakes and Structures
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• v.6 no.4
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• pp.351-373
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• 2014

This paper investigates the seismic response of lightweight acceleration-sensitive non-structural components (NSCs) mounted on irregular reinforced concrete (RC) primary structures (P-structures) using non-linear dynamic finite element (FE) analysis. The aim of this paper is to study the influence of NSC to P-structure vibration period ratio, peak ground acceleration, NSC to P-structure height ratio, and P-structure torsional behaviour on the seismic response of the NSCs. Representative constitutive models were used to simulate the behaviour of the RC P-structures. The NSCs were modelled as vertical cantilevers fixed at their bases with masses on the free ends and varying lengths so as to match the frequencies of the P-structures. Full dynamic interaction is considered between the NSCs and P-structures. A set of 21 natural and artificial earthquake records were used to evaluate the seismic response of the NSCs. The numerical results indicate that the behaviour of the NSCs is significantly influenced by the investigated parameters. Comparison between the FE results and Eurocode (EC8) predictions suggests that EC8 underestimates the response of NSCs mounted on the flexible sides of irregular RC P-structures when the fundamental periods and heights of the NSCs match those of the P-structures. The perceived cause of this discrepancy is that EC8 does not take into account the amplification in the dynamic response of NSCs induced by the torsional behaviour of RC P-structures.