• Journal of the Korean Solar Energy Society
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• v.27 no.2
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• pp.19-27
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• 2007

The previous study was conducted to develop an air source multi heat pump system that could be operated with the solar collector and air source heat exchangers as heat source of the system. There is a winter-sowing problems in air source multi heat pump system when the outdoor temperature goes down under freezing point. The winter-sowing problem was solved by adapting R-22 refrigerant as working fluid in the previous study. However, when the system operated at high temperature, another problems are come out such as overheating of the solar collector outlet which lead to the superheat of the compressor inlet of the heat pump system. The condition could deteriorates a compressor in some case. In this study, we installed the anti-superheating devices on the previously developed system. As results of system performance test, COP of the system with anti-superheating technique is 2.4. It is a little improved COP compare to previous study's 2.23. In the results of multi heat source heating system, during operating solar collector, COP is relatively high between $200\;W/m^2$ and $400\;W/m^2$ solar intensity. It is recommended to extend the study on performance optimization with balancing the solar collect and capacity of compressor at higher solar irradiation conditions.

• Journal of Pharmacopuncture
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• v.12 no.3
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• pp.41-47
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• 2009

Objectives : This experimental study was performed to investigate the efficacy of Fel Ursi, Bovis Calculus & Moschus pharmacopuncture solution manufactured with freezing dryness method to use eye drop. Methods : After administering Fel Ursi, Bovis Calculus & Moschus pharmacopuncture solution on bacterial species(Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans) which cause Keratitis, MIC(Minimum Inhibition Concentration) and the size of inhibition zone were measured. Anti-bacterial potency was also measured using the size of inhibition zone. Results : There was no response to MIC on bacterial species(Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans) after Fel Ursi, Bovis Calculus & Moschus pharmacopuncture solution was medicated. Conclusions : The present study suggests that Fel Ursi, Bovis Calculus & Moschus pharmacopuncture solution dosen't have anti-bacterial effects on bacterial species(Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans) which cause Keratitis. These study result recommends that more research on other herbal medicines of eye drop for Keratitis are required.

• Transactions of the Korean hydrogen and new energy society
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• v.32 no.5
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• pp.347-355
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• 2021

This paper is a study on the thermal design of printed circuit heat exchanger (PCHE) to supply cryogenic high pressure liquid hydrogen stored from hydrogen liquefaction process by using computational fluid dynamics (CFD). This PCHE should be thermally designed to raise the temperature of cryogenic liquid hydrogen to a desired temperature and also to be anti-icing to avoid any local freezing in hot channel. This research presents the effect of inlet velocity and inlet temperature of hydrogen, and the effect of flow configurations of co/counter-flow on thermal design of PCHE heat exchanger based on various CFD simulation analysis.

• Journal of Korea Multimedia Society
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• v.24 no.7
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• pp.849-859
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• 2021

Prostate cancer (PCa) is a fatal disease that occurs in men. In general, PCa cells are found in the prostate gland. Early diagnosis is the key to prevent the spreading of cancers to other parts of the body. In this case, deep learning-based systems can detect and distinguish histological patterns in microscopy images. The histological grades used for the analysis were benign, grade 3, grade 4, and grade 5. In this study, we attempt to use transfer learning and fine-tuning methods as well as different model architectures to develop and compare the models. We implemented MobileNet, ResNet50, and DenseNet121 models and used three different strategies of freezing layers techniques of fine-tuning, to get various pre-trained weights to improve accuracy. Finally, transfer learning using MobileNet with the half-layer frozen showed the best results among the nine models, and 90% accuracy was obtained on the test data set.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.829-834
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• 2002

Recently, research and development for a number of repairing material like an epoxy-based material and polymer-cementitious material as well as anti-washout underwater concrete have been carried out. But, the study on tile materials for the concrete structure exposed to a wetted condition is at a standstill and there are not any suitable reference data at a repairing work for the concrete structure at a splash as well as a structure under severe moisture condition. In this study, the material, called as “ceramic metal”, with an excellent mobility and plasticity as well as with a high bond strength and durability of freezing-thawing resistant properties under any environmental conditions was developed. And, the experimental evaluations for the utility wert widely performed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.150-151
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• 2016

In previous study, researchers studied development of early anti-freezing cement at low temperature (-5℃) using hydration characteristics of reduction slag. In this study, the durability of concrete using reduction slag was conducted. The experiment result, reduction slag makes high temperature and improves compressive strength due to quick setting. And then result of durability show that it is no problem. However, it is considered that further study is needed about high shrinkages which was indicated in dry shrinkage.

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.2
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• pp.191-197
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• 2001

In this study, the admixtures for agents for enduring cold weather used widely are collected and applied to cement mortar to analyze the strength development due to variation of curing temperature at early age. The test results show that anti-freezing admixture have some problems due to high chloride content, which may cause the corrosion of reinforcement embedded in concrete. However, the mortar applied by accelerator and another kind of agent for enduring cold weather produced by S company lead to delay of strength development in low temperature. Also, it is clarified that there are no significant problems for cement mortar in strength development due to low temperature if a suitable kind of agent enduring cold weather is used and cement mortar is cured for more than $7.5^{\circ}D.D$ at early age.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.5
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• pp.914-920
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• 2002

This experiment is carried out for test whether the addition temperament drugs of Danchisoyo-san have an anti-inflammatory effect and have suppression effect on immunocyte in the state of inflammation which induced by carageenan and zymosan. The freezing lyophilization powder which were extracted from Danchisoyo-san divided low dose group(200mg/kg-DSL) and high dose group(500mg/kg-DSH) and after melting in water, it was orally administered to the mouse. Compared with inflammation induced group which were induced by triggering-inflammation reagent carageenan and zymosan and normal contrast group, we measured the edema decrement effect, macrophage and spleen cell activation. 1. Danchisoyo-san has suppress inflammatory reaction induced by carrageenan. 2. Danchisoyo-san has suppress increasing activation of abdominal cavity macrophage cell in the carrageenan induced inflammation. 3. Danchisoyo-san has suppress increasing activation of spleen cell in the carrageenan induced inflammation. 4. Danchisoyo-san has suppress increasing activation of abdominal cavity macrophage in the zymosan induced inflammation. 5. Danchisoyo-san has suppress increasing activation of spleen cell in the zymosan induced inflammation. Based on the above result, Danchisoyo-san was improved its suppression effect to the inflammatory reaction through the suppression of spleen cell and macrophage activation. So we concluded that Danchisoyo-san is prospected as a anti-inflammatory agent to cure inflammation.

• International Journal of Highway Engineering
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• v.17 no.4
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• pp.77-87
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• 2015

PURPOSES: It is theoretically well known all over the world, that porous hot mixed asphalt (HMA) with hydrated Lime improves moisture and rutting resistance, and reduces pothole occurrence frequency, as well as the life cycle cost (LCC). METHODS : Addictive in the two different formations of the liquid anti-stripping Agent and powder Hydrated-Lime was applied in this investigation in order to obtain relatively clear results according to their types and conditions. Firstly, the moisture conditions were set, and applied to the porous HMA mixtures with hydrated lime (anti-stripping agent). Next, it was followed by a non-destructive test with the application of three freeze-thaw cycles, which were individually carried out thrice to compare the results of the dynamic moduli. Lastly, the hydrated lime effect related to moisture sensibility to porous HMA has been verified through the analysis of the modulus results regarding the change rate of dynamic modulus per n-cycle. RESULTS: It is clear from this investigation, that the dynamic modulus is inversely proportional to the change in temperature, as the graph representing the rigidity of the thermorheologically simple (TRS) material showed gradual decline of the dynamic modulus with the increase in temperature. CONCLUSIONS: The porous HMA mixture with the anti-stripping agent (hydrated Lime) has been found to be more moisture resistant to freezing and thawing than the normal porous HMA mixture. It is clear that the hydrated lime helps the HMA mixture to improve its fatigue resistance.

• Biomolecules & Therapeutics
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• v.13 no.3
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• pp.165-173
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• 2005

The main aim of this study was to investigate stress related activities of ginsenosides and their action mechanism. Control group and ginsenoside supplemented groups were exposed to stress while no-stress group was not done. Animals of each group (n=$8\~10$) were orally administerd 100 mg red ginseng extract (R-G), or 10 mg ginsenosides/kg body weight once a day. Animals were given materials for 5 days without stress, and then were given supplements for 5 days with restraint and electroshock stress. Mice were given materials for 5 days for experiments on anti-fatigue effect. After loading final stress, stress-related behavioral changes of experimental animals were examined and plasma corticosterone levels were measured. R-G and ginsenoside $Rb_{1}$ supplementation partially blocked the stress effects on locomotion and elevated plus-maze test in rats and mice. They also partially blocked stress induced behavioral changes such as freezing, smelling, face-washing, rearing behavior in rats. R-G and $Rb_{1}$ decrease adrenal gland size and plasma corticosterone level, which were increased by stress in rats. R-G increased enduring time on the Rota rod, cold water and horizontal wire, but $Rb_{1}$ didn't. Effects of $Rb_{1}$ on plusmaze test were inhibited by administration of flumazenil. These results suggest that $Rb_{1}$ is the main antistress principle in ginseng and it's effect is modulated by GABAnergic nervous system.