• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2583-2588
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• 2008

In the present experimental study, the regime limit and pressure drop of dry-plug flow (dry wall condition at the gas portions of plug flow) in round mini-channels has been investigated. The air-water mixture was flowed through the round mini-channels made of Teflon, where the tube diameters ranged from 1.26 to 2.06 mm. For the present experimental range, with decreasing of the tube diameter, the transition between the plug and slug flows (wet and dry) happened at the higher gas superficial velocity region, which were in good agreement with the previous flow pattern maps tested. On the other hand, the transition between the wet- and dry-plug flows was little affected by the change of the tube diameter. In the pressure drop of dry-plug flows, among the correlations tested, the Lee and Lee's (2008) correlation best fitted the measured pressure drop data within the mean deviation of 10% for the present experimental range.

• Nuclear Engineering and Technology
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• v.37 no.6
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• pp.525-536
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• 2005

The interfacial area transport equation dynamically models the changes in interfacial structures along the flow field by mechanistically modeling the creation and destruction of dispersed phase. Hence, when employed in the numerical thermal-hydraulic system analysis codes, it eliminates artificial bifurcations stemming from the use of the static flow regime transition criteria. Accounting for the substantial differences in the transport mechanism for various sizes of bubbles, the transport equation is formulated for two characteristic groups of bubbles. The group 1 equation describes the transport of small-dispersed bubbles, whereas the group 2 equation describes the transport of large cap, slug or chum-turbulent bubbles. To evaluate the feasibility and reliability of interfacial area transport equation available at present, it is benchmarked by an extensive database established in various two-phase flow configurations spanning from bubbly to chum-turbulent flow regimes. The geometrical effect in interfacial area transport is examined by the data acquired in vertical fir-water two-phase flow through round pipes of various sizes and a confined flow duct, and by those acquired In vertical co-current downward air-water two-phase flow through round pipes of two different sizes.

• Nuclear Engineering and Technology
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• v.39 no.4
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• pp.327-336
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• 2007

The influence of density differences on the mixing of the primary loop inventory and the Emergency Core Cooling (ECC) water in the downcomer of a Pressurised Water Reactor (PWR) was analyzed at the ROssendorf COolant Mixing (ROCOM) test facility. ROCOM is a 1:5 scaled model of a German PWR, and has been designed for coolant mixing studies. It is equipped with advanced instrumentation, which delivers high-resolution information for temperature or boron concentration fields. This paper presents a ROCOM experiment in which water with higher density was injected into a cold leg of the reactor model. Wire-mesh sensors measuring the tracer concentration were installed in the cold leg and upper and lower part of the downcomer. The experiment was run with 5% of the design flow rate in one loop and 10% density difference between the ECC and loop water especially for the validation of the Computational Fluid Dynamics (CFD) software ANSYS CFX. A mesh with two million control volumes was used for the calculations. The effects of turbulence on the mean flow were modelled with a Reynolds stress turbulence model. The results of the experiment and of the numerical calculations show that mixing is dominated by buoyancy effects: At higher mass flow rates (close to nominal conditions) the injected slug propagates in the circumferential direction around the core barrel. Buoyancy effects reduce this circumferential propagation. Therefore, density effects play an important role during natural convection with ECC injection in PWRs. ANSYS CFX was able to predict the observed flow patterns and mixing phenomena quite well.

• Journal of Soil and Groundwater Environment
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• v.25 no.2_spc
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• pp.55-69
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• 2020

Permeability-analyzing methods commonly involve small-scale drilling, such as pumping or slug test, but it is difficult to identify overall distribution of permeability of the entire target sites due to high cost and time requirement. Spectral induced polarization (SIP) method is known to be capable of providing distributions of both the porosity and the pore size, the two major parameters determining permeability of the porous medium. The relationship between SIP variables and permeability has been studied to identify the hydrological characteristics of target sites. Kozeny-Carman formula has been improved through many experiments to better predict fluid permeability with electrical properties. In this work, the permeability prediction techniques based on SIP data were presented in accordance with the hydrogeological and electrical characteristics of a porous medium. Following the summary of the techniques, various models and related laboratory experiments were analyzed and examined. In addition, the field applicability of the prediction model was evaluated by field case analysis.

• International Journal of Oral Biology
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• v.45 no.4
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• pp.152-161
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• 2020

D-pinitol is an analog of 3-methoxy-D-chiro-inositol found in beans and plants. D-pinitol has anti-inflammatory, antidiabetic, and anticancer effects. Additionally, D-pinitol induces apoptosis and inhibits metastasis in breast and prostate cancers. However, to date, no study has investigated the anticancer effects of D-pinitol in oral cancer. Therefore, in this study, whether the anticancer effects of D-pinitol induce apoptosis, inhibit the epithelial-to-mesenchymal transition (EMT), and arrest cell cycle was investigated in squamous epithelial cells. D-pinitol decreased the survival and cell proliferation rates of CAL-27 and Ca9-22 oral squamous carcinoma cells in a concentration- and time-dependent manner. Evidence of apoptosis, including nuclear condensation, poly (ADP-ribose) polymerase, and caspase-3 fragmentation, was also observed. D-pinitol inhibited the migration and invasion of both cell lines. In terms of EMT-related proteins, E-cadherin was increased, whereas N-cadherin, Snail, and Slug were decreased. D-pinitol also decreased the expression of cyclin D1, a protein involved in the cell cycle, but increased the expression of p21, a cyclin-dependent kinase inhibitor. Hence, D-pinitol induces apoptosis and cell cycle arrest in CAL-27 and Ca9-22 cells, demonstrating an anticancer effect by decreasing the EMT.

• The Journal of Engineering Geology
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• v.32 no.1
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• pp.127-142
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• 2022

This study explored the fluid transfer characteristics of simultaneous pneumatic blasting, plasma blasting, and vacuum suction (the PPV method), and assessed their effect. Chemical oxidation-an established soil remediation method-was compared as a control. Electrical resistivity surveys found that PPV reduced resistivity by about 1.5-2.5 times compared with the control group, indicating that it increased the diffusion of fluid between the injection and suction wells. Injection and suction tests comparing the injection flow rate, initial suction flow rate time, and suction flow rate showed that the PPV method offered an improvement over the existing method. Slug tests revealed that PPV increased the permeability coefficient by a greater amount than that by the control method. This study qualitatively and quantitatively confirmed that the PPV method clearly improves injection and suction efficiency by accelerating cracks in the ground and improving water permeability compared with the established chemical oxidation method.

• Journal of Ginseng Research
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• v.42 no.3
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• pp.288-297
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• 2018

Background: The incidence of colorectal cancer (CRC) is increasing, with metastasis of newly diagnosed CRC reported in a large proportion of patients. However, the effect of Korean Red Ginseng extracts (KRGE) on epithelial to mesenchymal transition (EMT) in CRC is unknown. Therefore, we examined the mechanisms by which KRGE regulates EMT of CRC in hypoxic conditions. Methods: Human CRC cell lines HT29 and HCT116 were incubated under hypoxic (1% oxygen) and normoxic (21% oxygen) conditions. Western blot analysis and real-time PCR were used to evaluate the expression of EMT markers in the presence of KRGE. Furthermore, we performed scratched wound healing, transwell migration, and invasion assays to monitor whether KRGE affects migratory and invasive abilities of CRC cells under hypoxic conditions. Results: KRGE-treated HT29 and HCT116 cells displayed attenuated vascular endothelial growth factor (VEGF) mRNA levels and hypoxia-inducible $factor-1{\alpha}$ ($HIF-1{\alpha}$) protein expression under hypoxic conditions. KRGE repressed Snail, Slug, and Twist mRNA expression and integrin ${\alpha}V{\beta}6$ protein levels. Furthermore, hypoxia-repressed E-cadherin was restored in KRGE-treated cells; KRGE blocked the invasion and migration of colon cancer cells by repressing $NF-{\kappa}B$ and ERK1/2 pathways in hypoxia. Conclusions: KRGE inhibits hypoxia-induced EMT by repressing $NF-{\kappa}B$ and ERK1/2 pathways in colon cancer cells.

• Korean Journal of Community Nutrition
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• v.14 no.4
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• pp.392-405
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• 2009

This study was conducted to investigate food and meal preference of workers (435 male and 212 female) in the Chonnam Yeosu industrial area. The results of the survey were analyzed by principal components analysis. The results were obtained as follows: 19.3% of the subjects were twenties, 28.3% were thirties, 28.8% were forties and 23.7% were fifties. Females liked rice rolled in dried laver, rice cakes, janchi-noodle and breads, on the other hand males liked thick beef soup, loach soup, an eel stew and soju. The young liked instant noodles, fried chicken, sweet and sour pork, pork cutlet, pizza, hamburger, ham, sausage and fruit beverage, on the other hand the old liked a fish pot stew, loach soup, eel stew, fish boiled in soy with spices, panfried fish, sea slug, ascidian, bunder, green laver and boiled burdock-lotus root in soy. Females who are young liked hamburger and sweet and sour pork whereas males who are young liked instant noodles, pork cutlet, ham, sausage and fruit beverage. Aged females liked fish boiled in soy with spices, panfried fish, bunder, green laver, boiled burdock-lotus root in soy whereas aged males liked a fish pot stew, loach soup, eel stew, sea mussel and oysters. Boiled rice was located within the middle irrespective of age and sex, but noodles, wheat flour meal, fast foods and fruits were situated at the young female side. Aged males liked soup and pot stew. Young males liked meats and eggs whereas fish and shellfish and kimch were located at the aged people side. Aged females liked sea weeds and most people disliked vegetables but females liked some vegetables irrespective of age. Processed foods, salted foods, and alcohol were generally disliked foods by subjects but males liked those foods. Soybean curd was liked more males than females, and teas, except coffee, was liked by males. (Korean J Community Nutrition 14(4) : 392${\sim}$405, 2009)

• The Korean Journal of Malacology
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• v.11 no.1
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• pp.78-91
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• 1995

한국산 산민달팽이(Incilaria frushtorferi)의 웅성생식기관 및 자웅공통생식기관에 대하여 조직화학적 방법을 이용하여 염색하고 광학현미경으로 관찰한 결과 다음과 같은 결론을 얻었다.1. 자웅동체관은 가늘고 꾸불꾸불하고 긴 관으로 대부분 성숙한 정자로 가득차 있었다. 이 관의 내강상피는 단충섬모상피와 단층섬모원주상피 그리고 위중층 원주상패 등 다양한 세포로 구성되어 있었다.2. 대자웅동체관은 위로 소자웅동체관과 알부민성이 있으며, 그 밑으로는 수란관과 연결되어 있었다.이들의 내강상피는 불규칙한 단층섬모원주상피로 구성되어 있으며, 결합조직내 선세포로부터 형성된 산성 및 중성 점액성 과립들이 기막을 통과하여 내강 속으로 분비되었다.3. 전립선의 내강은 키 큰 단층원주섬모세포로 구성되었으며, 결합조직 내의 분비과립세포에서 형성된 중성 점액과립을 상피세포를 통해 내강으로 분비하였다.4. 정관은 직경 0.5 x 0.25mm 정도인 타원형의 관상구조로 이루어져 있고, 이 관을 0.1mm정도의 매우 두터운 근육층이 둘러싸고 있었다.5. 수정관의 내강은 결합조직성 돌기에 의해 4부분으로 분지되어 있으며 내강은 키 큰 단층섬모원주상피세포로 구성되어 있었다. 또한 수정관 주위에는 두터운 환상근층이 둘러싸고 있었는데, 이들 사이에서 2종의 분비성 과립이 확인되었다.6. 상음경은 내강이 십자로 열려있으며, 키 큰 단층섬모원주상피와 단층입방상피세포로 구성되어 있었다. 내강을 구성하는 근육들은 매우 두터웁고 환상근층과 종주근층이 교대로 둘러싸고 있었다.7. 음겨은 상음경이 점점 굵어져서 형성된 큰 형성된 큰 생식기관으로 내강은 주름 형태인 많은 돌기들을 가지고 있었다. 내강상피 세포는 키가 단층원주상피세포와 단층입방상피가 부위에 따라 다르게 분포하고 있으며, 상피세포 및 결합조직에는 두터운 근육층이 있어 음경의강한 운동성이 감지 되었다.

• Journal of the Korean Geotechnical Society
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• v.15 no.6
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• pp.111-120
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• 1999

Leachate flow behavior due to intermediate cover soil of low hydraulic conductivity and the applicability of pumping method for reducing the leachate level in the landfill are analyzed with the numerical flow model, MODFLOW. Using the hydraulic conductivity and storativity data obtained from the field pumping and slug tests(Jang and Cho, 1999), the hydraulic condition within the landfill is validated. The optimum rate of pumping, the radius of influence, and the efficiency of horizontal drain are analyzed for reducing the leachate level in the landfill. From the results of the analyses, the barrier effect that the buried cover soil of low hydraulic conductivity prevents the vertical movement of leachate flow through the cover soil, which is found from the in-situ geotechnical studies(Jang and Cho, 1999), is identified again. Also, the installation of horizontal drains to the pumping well can increase the pumping rate from 120 ton/day per a well to 300 ton/day. The length of horizontal drain did not influence significantly on the drawdown-time curve of leachate in the landfill.