• Clean Technology
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• v.22 no.4
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• pp.299-307
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• 2016

These days, coal is one of the most important energy resources used for transportation, industry, and electricity. There are two types of coal: high-rank and low-rank. Low-rank coal has a low calorific value and contains large amounts of useless moisture. The quality of low-rank coal can be increased by simple drying technology and it needs to be stabilized by hydrocarbons (e.g. palm acid oil, PAO) to prevent spontaneous combustion and moisture re-adsorption. Spontaneous combustion becomes a major problem during coal mining, storage, and transportation. It can involve the loss of life, property, and economic value; reduce the quality of the coal; and increase greenhouse gas emissions. Besides spontaneous combustion, moisture re-adsorption also leads to a decrease in quality of the coal due to its lower heating value. In this work, PAO was used for additive to stabilize the upgraded coal. The objectives of the experiments were to determine the stabilization characteristic of coal by analyzing the behavior of upgraded coal by drying and PAO addition regarding crossing-point temperature of coal, the moisture behavior of briquette coal, and thermal decomposition behavior of coal.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.712-713
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• 2006

We successfully developed Al-Si-Transition Metal (TM) -Rare Earth (RE) Powder Metallurgy (P/M) alloy with fine microstructure, which has high strength at high temperature. This material was compacted rapidly solidified powder and directly consolidated by hot extruding or forging. Before consolidating, rapid heating was performed on powder compaction in order to keep the fine microstructure in powder state. We have also investigated the processing conditions of this new alloy by computing simulations and experiments.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.930-932
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• 2007

In order to understand the doping control for the belt source evaporation, the Alq3 and NPB were codeposited on the Ta plate to re-sublimate. The very slow heating $(0.1^{\circ}C/s)$ of the Ta plate shows the separated rate signals of Alq3 and NPB sublimated from the Alq3-mixed NPB organic film on Ta plate. The ratio of the vapor rates of Alq3 and NPB was measured as same as that of each sublimation rates. Therefore, the doping control of the belt source evaporation is of the ratio of the vaporization rates of host and dopants.

• Food Science and Preservation
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• v.14 no.1
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• pp.78-86
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• 2007

This study prepared extracts of Angelica dahurica leaves using reflux water extraction (RW), reflux ethanol extraction (RE) and pressure heating water extraction (PW). The extracts were extraction for levels of polyphenol compounds, antioxidant activities, and inhibitory potencies for xanthine oxidase and tyrosinase. The PW extraction method yielded the highest content of polyphenol compounds (95.23 mg/g). The electron donating abilities (EDAs) of RE and PW extracts were 76.02% and 70.08% respectively. The superoxide dismutase (SOD)-like activities were 13.45 19.00%, when extracts were assayed at 1 mg/mL. The nitrite scavenging ability (pH 1.2) of the PW extract was 54.33% higher than levels shown (44.24%) by the RE and RW extracts. The inhibition of xanthine oxidase by the RW extract was highest (99.71% at 5 mg/mL) while that of the PW extract was over 97% at 500 g/mL. Tyrosinase inhibition was highest in the RE extract (46.25% at 5 mg/mL). All extracts showed dose-dependent inhibitory activities. The results indicated that the PW extract had the highest polyphenol content, the RW and RE extracts had the best nitrite scavenging ability, and the RE extract showed the most pronounced effect on EDA, SOD-like activity and tyrosinase inhibition.

• The Korean Journal of Food And Nutrition
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• v.28 no.6
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• pp.1033-1044
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• 2015

During the Joseon period, kimchi was mostly made by heating the ingredients. Since salt was pricey at the time, in order to save salt and time, people used a method that involved destroying the cell wall by heating the vegetables. However, this method is no longer passed down. Thus, in this paper, we re-discovered how kimchi was made through heating while analyzing the recipes for kimchi during the Joseon period. There were 27 kinds of kimchi made through blanching. To keep the vegetables from becoming soggy, 2 kinds of kimchi were made by putting the ingredients in potassium aluminum sulfate water and 3 kinds were made through blanching the ingredients in limewater. There were 7 kinds of kimchi made by heating in vinegar, 5 kinds by boiling the ingredients, 6 kinds by stir-frying the ingredients, 2 kinds by stir-frying the ingredients with salt, and 3 kinds by steaming the ingredients. In order to eradicate unwanted germs, leaving only Lactobacillus, 25 kinds of kimchi were made by draining the boiled mixture. A total of 17 kinds of kimchi were made by heating the kimchi pot with compost including that of horses. For elders with weak teeth and poor digestion, 7 kinds of kimchi were made after heating, including 3 kinds of sukkkakdugi (cubed radish kimchi made with boiled radish). 3 kinds of chaekimchi (julienned kimchi) and 3 kinds of chaekkakdugi (kimchi with julienned radish) for elders existed as well.

• Journal of Ocean Engineering and Technology
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• v.31 no.6
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• pp.425-430
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• 2017

In order to reduce the cost of corrections and time needed for the block assembly process, the reverse setting method is applied for a back-heated block to neutralize deck deformation. The proper reverse setting shape for a back-heated block to correct deformation improved the deck flatness, but an excessive amount of reverse setting could inversely affect the flatness of the block. A prediction method was developed for the proper reverse setting shape using a back-heated block, considering the complex geometry of blocks, thickness of the deck plate, and thermal loading conditions such as welding and back-heating. The prediction method was developed by combining the re-meshing technique and inherent strain-based deformation analysis using the finite element method. Because the flatness deviation was decreased until the lower critical point and thereafter it tended to increase again, the optimum value for which the flatness was the best case was selected by repeatedly calculating the predefined reverse setting values. Based on this analysis and the study of the back-heating deformation of large assembly blocks, including the reverse setting shape, the mechanism for selecting the optimum reverse setting value was identified. The developed method was applied to the actual blocks of a ship, and it was confirmed that the flatness of the block was improved. It is concluded that the developed prediction method can be used to predict the optimum reverse setting shape value of a ship's block, which will reduce the cost of corrections in the construction stage.

• Corrosion Science and Technology
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• v.2 no.6
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• pp.283-288
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• 2003

The cathodic protection method is being widely used in marine structural steel, however a high tensile steel like RE 36 steel for marine structural steel is easy to get hydrogen embrittlement due to over protection during cathodic protection as well as preferential corrosion of HAZ(Heating Affected Zone) part. In this paper, corrosion resistance and mechanical properties such as elongation and hydrogen embrittlement were investigated with not only in terms of electrochemical view but also SSRT(Slow Strain Rate Test) method with applied constant cathodic potential, analysis of SEM fractography in case of both As-welded and PWHT(Post-Weld Heat Treatment) of $550^{\circ}C$. The best effect for corrosion resistance was apparently indicated at PWHT of $550^{\circ}C$ and elongation was increased with PWHT of $550^{\circ}C$ than that of As-welded condition. On the other hand. Elongation was decreased with applied potential shifting to low potential direction which may be caused by hydrogen embrittlement, however the susceptibility of hydrogen embrittlement was decreased with PWHT of $550^{\circ}C$ than that of As-welded condition and Q.C(quasi cleavage) fracture mode was also observed significantly according to increasing of susceptibility of hydrogen embrittlement. Eventually it is suggested that an optimum cathodic protection potential range not causing hydrogen embrittlernent is from -770 mV(SCE) to -850 mV(SCE) in As-welded condition while is from -770 mV(SCE) to -875 mV(SCE) in PWHT of $550^{\circ}C$.

• Journal of Life Science
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• v.14 no.1
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• pp.110-114
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• 2004

The optimized RAPD-PCR conditions, that can be utilized as a basic information for analysis of the gelletic characteristics were developed for genetic analysis of four mulberry varieties, named Milsung, Chungil, Suil, and Hansung using a primer, OPY15 (5'-AGTCGCCCTT-3') from Operon company. We tested several different factors for best PCR condition including concentrations of DNA, primer, Mgclu annealing temperature, number of PCR cycle, and prosence/absence of pre-heating time at the begining of PCR reaction in the $25 \mul$volume. The best RAPD profiles were obtained using 50 ng of DNA, 1 $\mu$M of primer, $1 \mum$of $MgCl_2\;,45^{\circ}C$ of annealing temperature and an absence of pre-heating time. An establishment of the stable and reproducible RAPD-PCR conditions are expected to be useful for the subsequent RAPD-related investigation, such as genetic characterization of the mulberry varieties, re-establishment of phylogenetic relationships and development of new varieties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.1
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• pp.20-26
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• 2007

We analyzed the contents of polyphenol compounds, the antioxidant activity and the physiological activity to investigate the functional effects of extracts from Angelica dahurica by the reflux water extraction (RW), reflux ethanol extraction (RE) and pressure heating water extraction (PW). The content of phenolic compounds of PW was the highest at 156.30 mg/g, and those of RW and RE were 31.69 mg/g and 26.34 mg/g, respectively. The electron donating ability (EDA) were in the range of 30.56% $\sim$ 52.74% and superoxide dismutase (SOD) like activity were 10.96% $\sim$ 23.24% at 1,000 ${\mu}g/mL$. The nitrite scavenging ability of PW at pH 1.2 was 61.47%, higher than those of RW (16.81%) and RE (17.78%). The xanthine oxidase inhibitory were 90.91% and tyrosinase inhibitory rate of RE was the highest (51.71%) at the concentration of 5,000 ${\mu}g/mL$. All extracts were increased with increments of the extract concentrations.

• International Journal of Air-Conditioning and Refrigeration
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• v.15 no.3
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• pp.108-113
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• 2007

The performance of a solar water heater incorporating evacuated tubes was evaluated using a transient simulation program, TRNSYS. Simulations were performed for $60^{\circ}C$ of hot water load temperature and for 280 liter of daily hot water volumes and three 400 liter of storage tank volumes. Three patterns of daily hot water consumption profile were used in the present study (morning, lunch and evening). The results show that the increase in solar fraction depends on the load profile, as well as the collector efficiency coefficient. Hot water draw profile has a large effect on the performance of the SDHWS, the morning load profile has the highest solar fraction. The annual solar fraction of the system, at the weather conditions of Jinju is approximately 84% at lunch load pattern, the 280 kg of load volume, 400 kg of tank volume and the $60^{\circ}C$ of load temperature.