• Textile Coloration and Finishing
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• v.31 no.1
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• pp.1-13
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• 2019

In this study, eco-friendly functional leather was developed by recycling wastes such as eel skin, marigold(Tagetas erecta l.), hinoki cypress(Chamaecyparis obtusa). The hot water extracts of marigold and hinoki cypress leaves were freeze-dried at $-80^{\circ}C$ to prepare colorant powder. The dyeing of eel leather with marigold was carried out to investigate the effects of dyeing conditions, mordanting on dye uptake, color, morphological change, and color fastness. Considering shrinkage of eel leather caused by dyeing, the optimum dyeing conditions were $60^{\circ}C$ of dyeing temperature and 60 min of dyeing time at 1:100 of bath ratio, and color of the dyed eel leather was Y to YR Munsell series. In order to prevent the degradation of leather from microbe, we conducted combination dyeing with marigold and hinoki cypress leave colorants. In this case, the combination dyed eel leathers showed excellent antimicrobial activity with above 99% bacterial reduction rate against S. aurieus and K. pneumoniae. It was confirmed that all of the dyed eel leathers were sufficient to meet the Korean Standard for color fastness of leather products. It can be applied practically for the development of eco-friendly functional leather by utilizing some useful active components extracted from plant resources and by recycling food wastes.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.3
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• pp.43-48
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• 2019

Since the revision of the Rationalization of Energy Use Law, the spread of new and renewable energy in buildings has been promoted. In addition, the production of electric power and thermal energy is an important issue in the change of energy paradigm centered on the use of distributed energy. Among them, geothermal energy is attracting attention as a high-performance energy-saving technology capable of coping with heating / cooling and hot water load by utilizing the constant temperature zone of the earth. However, there is a disadvantage that the initial investment cost is high as a method of calculating the capacity of a geothermal facility by calculating the maximum load. The disadvantages of these disadvantages are that the geothermal energy supply is getting stagnant and the design of the geothermal system needs to be supplemented. In this study, optimization design of geothermal system was carried out using optimization tool. As a result of the optimization, the ground heat exchanger decreased by 30.8%, the capacity of the heat pump decreased by 7.7%, and the capacity of the heat storage tank decreased by about 40%. The simulation was performed by applying the optimized value to the program and confirmed that it corresponds to the load of the building. We also confirmed that all of the constraints used in the optimization design were satisfied. The initial investment cost of the optimized geothermal system is about 18.6% lower than the initial investment cost.

• Nuclear Engineering and Technology
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• v.54 no.1
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• pp.97-109
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• 2022

Multi-dimensional coupling analysis is a research hot spot in nuclear reactor thermal hydraulic study and both the full-scale system transient response and local key three-dimensional thermal hydraulic phenomenon could be obtained simultaneously, which can achieve the balance between efficiency and accuracy in the numerical simulation of nuclear reactor. A one-dimensional to three-dimensional (1D-3D) coupling platform for the nuclear reactor multi-dimensional analysis is developed by XJTU-NuTheL (Nuclear Thermal-hydraulic Laboratory at Xi'an Jiaotong University) based on the CFD code Fluent and system code RELAP5 through the Dynamic Link Library (DLL) technology and Fluent user-defined functions (UDF). In this paper, the International Standard Problem (ISP) No. 43 is selected as the benchmark and the rapid boron dilution transient in the nuclear reactor is studied with the coupling code. The code validation is conducted first and the numerical simulation results show good agreement with the experimental data. The three-dimensional flow and temperature fields in the downcomer are analyzed in detail during the transient scenarios. The strong reverse flow is observed beneath the inlet cold leg, causing the de-borated water slug to mainly diffuse in the circumferential direction. The deviations between the experimental data and the transients predicted by the coupling code are also discussed.

• The Korea Journal of Herbology
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• v.24 no.1
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• pp.49-57
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• 2009

Objectives：I want to examine the antimicrobial activity of Gwankeibujalijung-tang against Streptococcus pneumoniae 59 isolated from the mouth of a common cold patient. Methods： Antimicrobial activity was assayed through the hot water extract from Gwankeibujalijung-tang against Streptococcus pneumoniae 59 isolated from the mouth of a common cold patient. Results： The size of inhibition zone of Gwankeibujalijung-tang extract was 9.83 $\pm$ 0.11 mm. The optimal pH and temperature for the growth of isolated Streptococcus pneumoniae 59 were 7.0 and 37$^{\circ}C$, respectively. The minimum inhibitory concentration of Gwankeibujalijung-tang extract was 12 $\mu\ell$ and the antimicrobial activity of Gwankeibujalijung-tang extract was not destroyed by the heat (121$^{\circ}C$ for 15 min) and not affected by pH. Conclusions： Reviewing this experimental result, it appeared that Gwankeibujalijung-tang had efficacy against Streptococcus pneumoniae 59 isolated from the mouth of a common cold patient.

• Journal of Ginseng Research
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• v.48 no.1
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• pp.1-11
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• 2024

Fresh ginseng is prone to spoilage due to its high moisture content. For long-term storage, most fresh ginsengs are dried to white ginseng (WG) or steamed for hours at high temperature/pressure and dried to form Korean Red ginseng (KRG). They are further processed for ginseng products when subjected to hot water extraction/concentration under pressure. These WG or KRG preparation processes affect ginsenoside compositions and also other ginseng components, probably during treatments like steaming and drying, to form diverse bioactive phospholipids. It is known that ginseng contains high amounts of gintonin lysophosphatidic acids (LPAs). LPAs are simple lipid-derived growth factors in animals and humans and act as exogenous ligands of six GTP-binding-protein coupled LPA receptor subtypes. LPAs play diverse roles ranging from brain development to hair growth in animals and humans. LPA-mediated signaling pathways involve various GTP-binding proteins to regulate downstream pathways like [Ca²⁺]_i transient induction. Recent studies have shown that gintonin exhibits anti-Alzheimer's disease and antiarthritis effects in vitro and in vivo mediated by gintonin LPAs, the active ingredients of gintonin, a ginseng-derived neurotrophin. However, little is known about how gintonin LPAs are formed in high amounts in ginseng compared to other herbs. This review introduces atypical or non-enzymatic pathways under the conversion of ginseng phospholipids into gintonin LPAs during steaming and extraction/concentration processes, which exert beneficial effects against degenerative diseases, including Alzheimer's disease and arthritis in animals and humans via LPA receptors.

• Resources Recycling
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• v.15 no.3 s.71
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• pp.38-45
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• 2006

The thermal filter press dewatering(TFPD) technology to improve the dewaterability through increasing the inner vapor pressure, lowering the filtration viscosity and forming the porosity easily within cake as applying the heat at the sludge layer was developed in this study. The hot water with temperature of $95^{\circ}C$ and pressure of $1.2kg_f/cm^2$ was supplied to the heating plate equipped between filter plates with plate size of $470{\times}470mm$ and material of polypropylene. Sludge was dewaterd by supplying pressure of $5kg_f/cm^2$ and then by squeezing pressure of $15kg_f/cm^2$. As a results of estimating the characteristics of thermal dewatering to consider the initial water content and organic content to be influenced by a period of water shortage and rainwater, the dewatered cake water content was about 35 wt% and dewatering velocity was $4DSkg/m^2{\cdot}hr$ under the rainwater period, and the dewatered cake water content was about 50 wt% and dewatering velocity was $1.5DSkg/m^2{\cdot}hr$ in the case of sludge of water shortage season. These results was superior to the mechanical dewatering performance with water content of 70wt% and dewatering velocity of $0.9DSkg/m^2{\cdot}hr$. On the base of the results of TFPD, energy consumpted to deal with DS(Dry Solid) of 1kg was estimated by 300 kJ. It was analyzed that the energy consumption of TFPD was decreased about one third with comparison to the dryer system. Dewatering velocity of this technology was faster than the one of mechanical dewatering equipment and it was easier to product low water content cake. Therefore, this technology was recognized that dewaterability was predominant because of the fast of dewatering velocity and production of low water content cake, and also this known as economical efficiency was excellent because of low energy consumption in comparison with dryer.

• Journal of Korean Tunnelling and Underground Space Association
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• v.18 no.5
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• pp.401-412
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• 2016

It is extremely difficult to apply conventional grouting methods to subsea tunnelling construction in the high water pressure condition. In such a condition, the rapid artificial freezing method can be an alternative to grouting to form a watertight zone around freezing pipes. For a proper design of the artificial freezing method, the influence of salinity on the freezing process has to be considered. However, there are few domestic tunnel construction that adopted the artificial freezing method, and influential factors on the freezing of the soil are not clearly identified. In this paper, a series of laboratory experiments were performed to identify the physical characteristics of frozen soil. Thermal conductivity of the frozen and unfrozen soil samples was measured through the thermal sensor adopting transient hot-wire method. Moreover, a lab-scale freezing chamber was devised to simulate freezing process of silica sand with consideration of the salinity of pore-water. The temperature in the silica sand sample was measured during the freezing process to evaluate the effect of pore-water salinity on the frozen rate that is one of the key parameters in designing the artificial freezing method in subsea tunnelling. In case of unfrozen soil, the soil samples saturated with fresh water (salinity of 0%) and brine water (salinity of 3.5%) showed a similar value of thermal conductivity. However, the frozen soil sample saturated with brine water led to the thermal conductivity notably higher than that of fresh water, which corresponds to the fact that the freezing rate of brine water was greater than that of fresh water in the freezing chamber test.

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.556-566
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• 2010

A new kinetic spectrophotometric method is developed for the measurement of Mn(II) in natural water samples. The method is based on the catalytic effect of Mn(II) with the oxidation of Gallocyanin by $KIO_4$ using nitrilotriacetic acid (NTA) as an activation reagent at 620 nm. The optimum conditions obtained are $4.00{\times}1^{-5}\;M$ Gallocyanin, $KIO_4$, $1.00{\times}10^{-4}\;M$ NTA, 0.1 M HAc/NaAc buffer of pH = 3.50, the reaction time of 5 min and the temperature of $30^{\circ}C$. Under the optimum conditions, the proposed method allows the measurement of Mn(II) in a range of $0.1\;-\;4.0\;ng\;mL^{-1}$ and with a detection limit of down to $0.025\;ng\;mL^{-1}$. The recovery efficiency in measuring the standard Mn(II) solution is in a range of 98.5 - 102%, and the RSD is in a range of 0.76 - 1.25%. The newly developed kinetic method has been successfully applied to the measurement of Mn(II) in both some environmental water samples and certified standard reference river water sample, JAC-0031 with satisfying results. Moreover, few cations and anions interfere with the measurement of Mn(II). Compared with the other catalytic-kinetic methods and instrumental methods, the proposed kinetic method shows fairly good selectivity and sensitivity, low cost, cheapness, low detection limit and rapidity. It can easily and successfully be applied to the real water samples with relatively low salt content and complex matrices such as bottled drinking water, cold and hot spring waters, lake water, river water samples.

• Journal of Bio-Environment Control
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• v.22 no.2
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• pp.87-90
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• 2013

The average annual and winter ambient air temperatures in Korea have risen by $0.7^{\circ}C$ and $1.4^{\circ}C$, respectively, during the last 30 years. Due to climate change, the occurrence of abnormal weather conditions has become more frequent, causing damage to vegetable crops grown in Korea. Hot pepper, chinese cabbage and radish, the three most popular vegetables in Korea, are produced more in the field than in the greenhouse. It has been a trend that the time for field transplanting of seedlings is getting earlier and earlier as the spring temperatures keep rising. Seedlings transplanted too early in the spring take a longer time to resume the normal growth, because they are exposed to suboptimal temperature conditions. This experiment was carried out to figure out the change of cellular tissue of chinese cabbage under the condition of low temperature to provide the information regarding the coming climatic change, on the performance of 'Chunkwang' chinese cabbage during the spring growing season. In our study, plant height, number of leaf, chlorophyll and leaf area was lower at the open field cultivation than heating house treatment after transplanting 50 days. Especially in fresh weight, compared with heating treatment, open field and not heated treatment were notably low with the 1/3 level. Of damage symptoms due to low temperature cabbage leaves about 10 sheets when $-3.0^{\circ}C$ conditions in chinese cabbage was a little bit of water soaking symptoms on the leaves. $-7.4^{\circ}C$ under increasingly severe water soaking symptoms of leaf turns yellow was dry. Microscopy results showed symptoms of $-3.0^{\circ}C$ when the mesophyll cell of palisade tissue and spongy tissue collapse, $-7.4^{\circ}C$ palisade tissue and spongy tissue was completely collapsed. The result of this study suggests that the growers should be cautioned not to transplant their chinese cabbage seedlings too early into the field, and should be re-transplanting or transplanting other plants if chinese cabbage are exposed to suboptimal temperature conditions ($-3.0^{\circ}C$ or $-7.4^{\circ}C$).

• Journal of Bio-Environment Control
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• v.15 no.2
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• pp.125-137
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• 2006

Pleurotus eryngii is one of the most promising mushrooms produced on the domestic farms. The quality as well as quantity of Eryngii is sensitively affected by micro climate factors such as temperature, relative humidity, $CO_2$ concentration, and light intensity. To safely produce high-quality Eryngii all the yew round, it is required that the environmental factors be carefully controlled by well designed structures equipped with various facilities and control systems. At the commercial mushroom cultivation houses of permanent frame type (A, B), this study was carried out to find out reasonable range of each environmental factor and yield together with economic and safe structures influencing on the optimal productivity of Eryngii. This experiment was conducted for about two-year ken Nov. 2003 to Dec. 2005 in cultivation house. Ambient temperature during the experiment period was not predominantly different from that of a normal year. The capacity of the hot water boiler and the piping systems were not enough. Because the capacity of electric heater and air circulation were not enough, air temperatures in cultivation house before improvement of system were maintained somewhat lower than setting temperature, and maximum air temperature difference between the upper and lower growth stage during a heating time period was about 5.1. But the air temperatures after system improvement were maintained within the limits range of setting temperature without happening stagnant of air. Air temperature distribution was generally distributed uniform. Relative humidity in cultivation house before , improvement was widely ranged about $44{\sim}100%$. But as the relative humidity after improvement was ranged approximately $80{\sim}100%$, it was maintained within the range of relative humidity recommended. And $CO_2$ concentration was maintained about $400{\sim}3,300mg{\cdot}L^{-1}$ range. The illuminance in cultivation house was widely distributed in accordance with position, and it was maintained lower than the recommended illuminance range $100{\sim}200lx$. The acidity of midium was some lower range than the recommend acidity range of pH $5.5{\sim}6.5$. The yield was relatively ununiform. In case of bottle capacity of 1,300cc, the mushroom of the lowest grade was less than 3%. The consumption electric energy was quite different according to the cultivation season. The electric energy consumed during heating season was much more than that of cooling season.