• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.3C
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• pp.95-104
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• 2012

Due to current interest in creation of urban space and urban landscape, more emphasis has been placed on underground space development. With increasing number of underground power cables and its importance, a study of backfill materials for pipe is now imperative. Backfill materials require outstanding thermal characteristics since breakdown of cable insulation can be caused if heat generated from transmission of underground power cables had not been effectively discharged through backfill materials. Also, coal ash, which are industrial by-products, is being produced in high volume every year. Among them, ponded ash (PA) is not recycled and instead, mostly buried. Therefore in this study, thermal conductivity test based on mixture ratio (PA, ponded ash : FA, fly ash) was performed to evaluate the thermal conductivity characteristics of CLSM (controlled low strength materials) with coal ash. The results indicate that the mixture ratio (PA, ponded ash : FA, fly ash) of 80:20, water contents of 28~30%, and cement contents of 7-11% showed the highest conductivity at 0.796~0.884W/mK and thus, considered optimal in terms of recycling ponded ash (PA) as well as for maximizing utilization as backfill materials for pipe in underground.

• Progress in Medical Physics
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• v.13 no.1
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• pp.1-8
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• 2002

Accurate knowledge of the distribution of contamination electrons ( which comes from mainly gantry head by Compton scattering, pair production, and tray: henceforth called leptons ) at the surface and in the first centimeters of tissue is essential for the clinical practice of radiation oncology. Such lepton tends to reduce or eliminate the ‘skin-sparing’ advantage of megavoltage photon beam radiotherapy, This information is needed to prescribe a absorbed dose to a skin volume at a few millimeter depth in high energy therapeutic radiation photon beam All experiments were done with 15 MV photon beam from a dual energy linear accelerator (Clinac 1800, Varian). Field size is defined by ranged from 10.0$\times$10.0 to 30.0$\times$30.0 $\textrm{cm}^2$. The absorbed dose and distribution of leptons in therapeutic radiation beam (15 MV) are investigated by means of variable blocked beams of 30.0$\times$30.0 $\textrm{cm}^2$ and dose beam profiles partly removed leptons with a copper plate. A numerous leptons mainly are distributed as shape of broad cone in the central photon beam and leptons path length in the water are shorter than 2.5 cm because of the leptons energy having around 3.0 MeV. These results clearly appears that the subtraction of leptons from the total depth dose curve not only lower the absolute dose in the buildup region and surface dose, it also causes a shift of d$_{max}$ to a deeper depth.

• Journal of Adhesion and Interface
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• v.18 no.2
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• pp.75-81
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• 2017

In this study, we synthesized mesoporous carbon (Carbonized Ni-FDU-15) containing nanoporous structures and magnetic nanoparticles. Carbonized Ni-FDU-15 was synthesized via evaporation-induced self-assembly (EISA) and direct carbonization by using a triblock copolymer (F127) as a structure-directing agent, a resol precursor as a carbon-pore wall forming material, and nickel (II) nitrate as a metal ion source. The mesoporous carbon has a well-ordered two-dimensional hexagonal structure. Meanwhile, nickel (Ni) metal and nickel oxide (NiO) were produced in the magnetic nanoparticles in the pore wall. The size of the nanoparticles was about 37 nm. The surface area, pore size and pore volume of Carbonized Ni-FDU-15 were $558m^2g^{-1}$, $22.5{\AA}$ and $0.5cm^3g^{-1}$, respectively. Carbonized Ni-FDU-15 was found to move in the direction of magnetic force when magnetic force was externally applied. The magnetic nanoparticle-bearing mesoporous carbons are expected to have high applicability in a wide variety of applications such as adsorption/separation, magnetic storage media, ferrofluid, magnetic resonance imaging (MRI) and drug targeting, etc.

• Food Science and Preservation
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• v.14 no.4
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• pp.369-377
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• 2007

This study investigated the effect of ginseng products on the baking properties of white breads. Flour was substituted by ginseng products (ginseng at levels 2, 4, 6, and 8%, all w/w, of flour levels). Both ginseng powder (GP) and red ginseng powder (RGP) were used. Similarly, red ginseng extract (RGE) was substituted at levels of 1, 2, 3, and 4% (all w/w) of flour. The physical properties of each dough were assessed using farinograms, extensograms, and amylograms. Water absorption increased as the proportions of ginseng products rose. The dough surface areas and R/E (resistance/extensibility) values decreased, as did peak viscosities, at the proportions of ginseng products increased. The pH values during fermentation decreased as the proportions of ginseng products increased. The fermentation power of dough with GP was lower than that of control, and higher than that of dough with RGP or RGE, but the addition of ginseng products beyond certain levels weakened the gas retention power: The specific loaf volumes of breads with 2% GP were the highest at 5.41 mL/g. In breads with RGE, the specificloaf volume increased from 5.52 mL/g to 5.82 mL/g as RGE levels rose from 0% to 4%. Hardness increased with rising GP and RGP levels in breads with GP and RGP, but decreased with RGE levels in breads with RGE. The moisture contents of breads during storage tended to be higher than control in breads with ginseng products. Lightness increased with addition of GP and decreased upon addition of RGP or RGE, while redness and yellowness increased after addition of any ginseng products. In sensory evaluation tests, the sensory scores for texture, color, mouth feel, and overall acceptability, were high, when any ginseng product (GP, RGP or RGE) was present at 2%. Of these breads, the bread with 2% RGE attained the highest sensory score.

• International Commerce and Information Review
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• v.18 no.1
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• pp.55-78
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• 2016

This paper discusses on Electronic Payment System between U.S.A. and Canada. In particular, I focused on ACSS compare with FedACH(Fed Automated Clearing House) to advance a research effects. Because both of them is a low-value, high-volume retail payment system which their countries represent. The ACSS(Automated Clearing Settlement System) is the system through which the vast majority of CPA payment items are cleared, through various payment streams. In 2014, ACSS system cleared approximately 6.8billion payments worth a total value of $ 44.9 trillion. While, The FedACH Network are the center of America Commerce, moving more than $40 trillion each year. That's made up of almost 23 billion electronic financial transaction, including direct deposit via ACH, social security and government benefits, electronic bill payments such as utility and mortgage payments. Thus in this article, first of all, I considered features of payment system and the types of payment items between ACSS and FedAch. Second, I analyzed the status of central bank and legal background. Third, I focused on the operational policy and risk aversion policy. Lastly, I suggested that their payment and banking system have to assume, with good reason, more efficiently accurately and securely operation to protect their customer from credit risk and financial fraud.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.5
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• pp.394-404
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• 2007

Oral squamous cell carcinoma is the most prevalent oral cancer, which is characterized by its high metastasis and recurrent rates and poor prognosis. Taxol is an anticancer agent which is microbial products extracted from jew tree. It combines with the tubulin and induces apoptosis by inhibiting mitosis of cell with microtubule stabilization. Recently, it was reported to be effective in various solid tumors, but only very slight effect has been seen in oral squamous cell carcinomas due to its cell-specific potencies. Cyclosporin A is used as immune suppressant and is being applied in anticancer therapy as its mechanism of induction of change of apoptotic process in various cells have been known. In this study, oral squamous cell carcinoma HN22 cell line was used for in vitro experiment and as for the experimental group taxol and cyclosporin A were applied alone and to observe the synergistic effect of apoptosis, Taxol and cyclosporin A were coadministered with different concentration of taxol for comparison. The results were obtained as follow: 1. There was no difference in Bcl-2, Bax, caspase 3, 8, 9 mRNA expression when cyclosprin A or taxol was applied alone to HN 22 cell line. 2. Caspase 3, 9 mRNA expression was prominently increased when cyclosprin A and taxol were applied together to cancer cell. 3. No significant difference was observed when cyclosporin A and taxol($1{\mu}g/ml$ and $3{\mu}g/ml$) were applied together to cancer cell line. 4. No significant difference was seen in Bcl-2, Bax, and caspase 8 mRNA expression in all the groups of in vitro experiments. 5. When cyclosporin A was applied alone in vivo study on the nude mice, histopathologi cal findings was similar to those of the control group. Oral squamous cell carcinoma induced by inoculation of HN 22 cell line was not reduced after treatment of cyclosporin A. 6. When taxol was applied alone, the islands of squamous cell carcinoma still remained, which meant insignificant healing effect. There was a lesser volume increase compared with the cyclosporin A alone. 7. When taxol and cyclosporin A were applied together, the connective tissue and calcification were seen in the histopathologic findings. Oral squamous cell carcinoma was decreased and cancer cell was disappeared. In observing the tumor mass change with time, there was a gradual decreased size and healing features. As the results of the in vitro experiment, it could conclud that only when the two agents are applied together, mitochondria-mediated apoptosis occurred by considerable increase of caspase 3, 9 mRNA expression, irrespectable of the concentration of taxol. In vivo experiment, there was a discrete synergistic effect when the two agents were applied together. But single use of cyclosporin A was not effective in this study. Based on the results of this experiment, if further clinical studies are done, taxol and cyclosporin A could be effectively used in treatment of oral squamous cell carcinomas.

• The Korea Journal of Herbology
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• v.30 no.6
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• pp.69-75
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• 2015

Objectives : This study was designed to investigate effects of the combination with Korean Red Ginseng (Panax ginseng C.A. Meyer), Gastrodia Rhizoma (Gastrodia elata Blume) and Polygoni Multiflori Radix (Polygonum multiflorum Thunberg) on metabolic disorders including cholesterol and erectile dysfunction in hyperlipidemia rats.Methods : Animals were divided into six groups; Control with normal diet, high fat/cholesterol-diet (HFCD), fluvastatin, Korean Red Ginseng treated (KRG), and the combination treated (Korean Red Ginseng, Gastrodia Rhizoma and Polygoni Multiflori Radix; 1:1:1 for KGP1 and 2:1:1 for KGP2). The experimental groups initially received HFCD for 10 weeks and then treated orally with fluvastatin, KRG, KGP1 and KGP2 during the final 6 weeks. Erectile function was determined by the measurements of intracavernosal pressure (ICP) and maximal arterial pressure (MAP) after electrical stimulation of the cavernosal nerve.Results : KGP2 decreased the level of total cholesterol and LDL cholesterol in the sera of HFCD rats without no changes of body weights. KRG, KGP1 and KGP2 decreased the level of C-reactive protein (CRP) levels except of fluvastatin, synthetic HMG-CoA reductase inhibitor. KRG, KGP1 and KGP2 significantly increased the ICP, ICP/MAP ratio, area under the curve (AUC) compared with those of normal rat. Morphometric analyses showed that KRG, KGP1 and KGP2 increased the volume of smooth muscle and the regular arrangement of collagen fibers in corpus cavernosum of HFCD rats. The penile expression of eNOS was increased by KRG, KGP1 and KGP2.Conclusions : Based on these results, we suggest that the combination with Korean Red Ginseng, Gastrodia Rhizoma and Polygoni Multiflori may improve hyperlipidemia through regulating the lipid profiles and erectile dysfunction in rats.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.3
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• pp.9-23
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• 2015

A lane change maneuver which has a high driver cognitive workload and skills sometimes leads to severe traffic accidents. In this study, the Advanced Lane Change Assist System (ALCAS) was developed to assist with the automatic lane changes in merging sections which is mainly based on an automatic control algorithm for detecting an available gap, determining the Optimal Lane Change Start Point (OLCSP) in various traffic conditions, and positioning the merging vehicle at the OLCSP safely by longitudinal automatic controlling. The analysis of lane change behavior and modeling of fundamental lane change feature were performed for determining the default parameters and the boundary conditions of the algorithm. The algorithm was composed of six steps with closed-loop. In order to confirm the algorithm performance, numerical scenario tests were performed in various surrounding vehicles conditions. Moreover, feasibility of the developed system was verified in microscopic traffic simulation(VISSIM 5.3 version). The results showed that merging vehicles using the system had a tendency to find the OLCSP readily and precisely, so improved merging performance was observed when the system was applied. The system is also effective even during increases in vehicle volume of the mainline.

• Clean Technology
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• v.22 no.4
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• pp.308-315
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• 2016

$SiO_x/ZnO$ composites were prepared from sol-gel method for excellent cycle life characteristics. The composites were coated by PVC as a carbon precursor. ZnO removal to create a void space therein was able to buffer the volume change during charge and discharge. To determine the crystal structure and the shape of the synthesized composite, XRD, SEM, TEM analysis was performed. The carbon contents in the composites were confirmed by TGA. The pore structure and pore size distribution of the composite was measured with the BET specific surface area analysis and BJH pore size distribution. Enhanced electric conductivity by carbon addition was determined from powder resistance measurement. Electrochemical properties were measured with the AC impedance and the charge and discharge cycle life characteristics. When carbon was coated on the $SiO_x/ZnO$ sample, the electrical conductivity and the discharge capacity were increased. After removal of ZnO with HCl the surface area of the sample was increased, but the discharge capacity was decreased. $SiO_x/ZnO$ sample without acarbon coating showed very low discharge capacity, and after carbon coating the sample showed high discharge capacity. For cycle life characteristics, $C-SiO_x/ZnO$ composite (Zn : Si : C = 1 : 1 : 8) with a capacity of $815mAh\;g^{-1}$ at 50 cycle and 0.2 C has higher capacity than existing graphite-based anode materials.

• Korean Journal of Agricultural Science
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• v.37 no.2
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• pp.199-207
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• 2010

This research was conducted to determine the influence of physiological and chemical properties of root substrates on the growth of the daughter plants of 'Maehyang' strawberry produced by bag culture. The daughter plants produced by stock plants during bag culture were individually separated and grown in 10-cm diameter plastic pots containing six different formulations of root substrates: a) 50% peatmoss plus 50% vermiculite (5:5 by volume, A), b) 70% peatmoss plus 30% perlite (7:3, B), c) 70% coir dust plus 30% perlite (7:3, C), d) mixture of 35% coir dust, 35% peatmoss, and 30% perlite (3.5:3.5:3.0, D), e) mixture of 20% rice hull, 70% coir dust, and 10% perlite (2:7:1, E), and f) 30% rice hull plus 70% coir dust (30:70, F). The container capacity and air filled porosity of the growing medium varied greatly among the six substrate formulations evaluated. The substrates E and F had less container capacity and higher air-holding spaces than the rest of the formulations. Therefore, these two formulations (E and F) may cause a problem in water management during the production of healthy daughter plants. The substrate formulations A, B, and D retained higher nitrogen (N) concentrations than other formulations containing coir dust or rice hull. The substrate formulations E and F which contained rice hull had lower N, phosphorus (P), and potassium(K) concentrations than other substrate formulations containing coir. The quality of the daughter plants grown in all six different substrate formulations was good with the crown diameters at around 10 mm. Fresh weights of the daughter plants grown in substrate formulations A, C, and D were higher than those obtained from B, E, and F. Dry weights of the daughter plants showed a similar trend. The daughter plants having high fresh and dry weights and increased crown diameter are in demand by the industry. For this reason, the substrate formulations A, C and D can readily be used as potting mixes during the production of 'Maehyang' strawberry transplants utilizing the bag culture system.