• Journal of Wetlands Research
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• v.8 no.3
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• pp.79-89
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• 2006

The survival rate and tube number of Monocorophium uenoi, one of the dominant species in Lake Sihwa, was investigated under laboratory condition with salinity gradients (1, 5, 10, 15, 20, 25, 30, 35, 40‰). Another laboratory experiments were conducted to investigate the survival rate of Monocorophium uenoi in sulphide-rich sediment with oxic overlying water, and the effect of amphipod bioturbation on sulphide and oxygen profiles. The survival rate and tube-forming number of the amphipod were high in salinity range of 20 to 30‰. The amphipod survival rate was also high in sulphidic sediment when the water column was oxic. The amphipod bioturbation affected the oxygen and sulphide content in the sediment; oxygen conditions in the upper sediment layers were improved, and simultaneously the concentrations of sulphide were reduced. And their depth was clearly dependent on amphipod density. In Lake Sihwa, previously anoxic bottoms with sulphidic sediment during summer turn oxic with pycnocline disappearance during autumn. Amphipods seem to have the capability to quickly invade such areas, and their tubing of the sediment may play an important role in preparing the sediment for further recolonisation of other macrobenthos.

• The Journal of Internal Korean Medicine
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• v.30 no.1
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• pp.107-118
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• 2009

Objectives : This study was aimed to investigated the effect of Yijin-tang on gastric motility and its mechanism of action in normal intact and partial pyloric obstructed rats. Methods : Gastric emptying was measured by the number of glass beads expelled from the stomach (containing one hundred of glass beads. ${\phi}1mm$) in 1 hour or 2 hours after glass beads and test drugs (normal saline. Yijin-tang 90mg/kg. Yijin-tang 270mg/kg) administration in normal intact and partial pyloric obstructed rats. In another series of experiments to evaluate the mechanism of Yijin-tang 270mg/kg under delayed conditions, normal intact rats were treated with atropine sulfate (1mg/kg,s.c.), cisplatin (10mg/kg,i.p.), quinpirole HCI (0.3mg/kg,i.p.) and NAME (NG-nitro-L-arginine methyl ester. 75mg/ kg,s.c.), respectively. Partial pyloric obstructed rats were modified by wrapping the nonabsorbable rubber ring (D :6mm, W:4mm, T: 1mm) around the 1st portion of the duodenum for 8 weeks. The myoelectrical activity of the gastric smooth muscle was recorded by a bipolar electrode placed at the abdominal surface in normal intact and partial pyloric obstructed rats. The gastric myoelectrical activity was measured for 30 minutes before and after orogastric administration of each solution (normal saline, Yijin-tang 270mg/kg) and expressed as dominant frequency, percent of normogastria and power ratio. Results : Yijin-tang improved gastric emptying more than normal saline in normal intact(p<0.001) and partial pyloric obstructed rats(p=0.002). Under the delayed gastric emptying induced by atropine sulfate, cisplatin, quinpirole HCI and NAME. Yijin-tang enhanced gastric emptying significantly in the cisplatin treated group(p<0.001). but didn't in other treated groups. Administration of Yijin-tang 270mg/kg has no significant effect on the myoelectrical activity of the gastric smooth muscle in both normal intact rats and partial pyloric obstructed rats. Conclusions : Yijin-tang seems to stimulate the gastric motility through suppressing the 5HT3 receptor and promoting the antroduodenal flow. We expect that Yijin-tang would be effective especially in dysmotility-like functional dyspepsia with partial pyloric obstruction or the side effects of cisplatin such as nausea, vomiting, abdominal discomfort, and delay of gastric emptying.

• Biomolecules & Therapeutics
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• v.25 no.3
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• pp.279-287
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• 2017

The chemical property of cinnamaldehyde is unstable in vivo, although early experiments have shown its obvious therapeutic effects on viral myocarditis (VMC). To overcome this problem, we used cinnamaldehyde as a leading compound to synthesize derivatives. Five derivatives of cinnamaldehyde were synthesized: 4-methylcinnamaldehyde (1), 4-chlorocinnamaldehyde (2), 4-methoxycinnamaldehyde (3), ${\alpha}$-bromo-4-methylcinnamaldehyde (4), and ${\alpha}$-bromo-4-chlorocinnamaldehyde (5). Neonatal rat cardiomyocytes and HeLa cells infected by coxsackievirus B3 (CVB3) were used to evaluate their antiviral and cytotoxic effects. In vivo BALB/c mice were infected with CVB3 for establishing VMC models. Among the derivatives, compound 4 and 5 inhibited the CVB3 in HeLa cells with the half-maximal inhibitory concentrations values of $11.38{\pm}2.22{\mu}M$ and $2.12{\pm}0.37{\mu}M$, respectively. The 50% toxic concentrations of compound 4 and 5-treated cells were 39-fold and 87-fold higher than in the cinnamaldehyde group. Compound 4 and 5 effectively reduced the viral titers and cardiac pathological changes in a dose-dependent manner. In addition, compound 4 and 5 significantly inhibited the secretion, mRNA and protein expressions of inflammatory cytokines TNF-${\alpha}$, IL-$1{\beta}$ and IL-6 in CVB3-infected cardiomyocytes, indicating that brominated cinnamaldehyde not only improved the anti-vital activities for VMC, but also had potent anti-inflammatory effects in cardiomyocytes induced by CVB3.

• Applied Chemistry for Engineering
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• v.31 no.2
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• pp.147-152
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• 2020

In this study, we dedicated to optimize the process for a reactive diluent for epoxy resin of improved chemical resistance by using cardanol, a component of natural oil of cashew nut shell liquid (CNSL). The central composite design (CCD) model of response surface methodology (RSM) was used for the optimization. The quantitative factors for CCD-RSM were the cardanol/ECH mole ratio, reaction time, and reaction temperature. The yield, epoxy equivalent, and viscosity were selected as response values. Basic experiments were performed to design the reaction surface analysis. The ranges of quantitative factors were determined as 2~4, 4~8 h, and 100~140 ℃ for the cardanol/ECH reaction mole ratio, reaction time, and reaction temperature, respectively. From the result of CCD-RSM, the optimum conditions were determined as 3.33, 6.18 h, and 120 ℃ for the cardanol/ECH reaction mole ratio, reaction time, and reaction temperature, respectively. At these conditions, the yield, epoxy equivalence, and viscosity were estimated as 100%, 429.89 g/eq., and 41.65 cP, respectively. In addition, the experimental results show that the error rate was less than 0.3%, demonstrating the validity of optimization.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.35 no.3
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• pp.187-194
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• 2017

The present study introduces a method to parallelize k-means clustering algorithm for fast unsupervised classification of large satellite imagery. Known as a representative algorithm for unsupervised classification, k-means clustering is usually applied to a preprocessing step before supervised classification, but can show the evident advantages of parallel processing due to its high computational intensity and less human intervention. Parallel processing codes are developed by using multi-threading based on OpenMP. In experiments, a PC of 8 multi-core integrated CPU is involved. A 7 band and 30m resolution image from LANDSAT 8 OLI and a 8 band and 10m resolution image from Sentinel-2A are tested. Parallel processing has shown 6 time faster speed than sequential processing when using 10 classes. To check the consistency of parallel and sequential processing, centers, numbers of classified pixels of classes, classified images are mutually compared, resulting in the same results. The present study is meaningful because it has proved that performance of large satellite processing can be significantly improved by using parallel processing. And it is also revealed that it easy to implement parallel processing by using multi-threading based on OpenMP but it should be carefully designed to control the occurrence of false sharing.

• Horticultural Science & Technology
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• v.16 no.2
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• pp.239-241
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• 1998

The experiments were carried out to improve culture efficiency of rhizome and mericlone propagation through settlement of problems occurring during culture period of temperate Cymbidium species. Shooting efficiency from rhizome of C. forrestii 'Nokwoon' was improved, when cultured in $H_3P_4$ medium (Hyponex 3+peptone 4g/L) supplemented with 170mg/L $NaH_2PO_4{\cdot}H_2O$ and 0.4mg/L Thiamin e HCl, but the other varieties were not influenced to shooting efficiency by additives. Medium in which rhizome of C. nishiuchianum 'Hodukjiwha' was cultured became less browned in $H_3P_4$ medium added with 150mg/L PVP, but the other treatments of antioxidants was failed to prevent the medium browning. Re-formation of rhizome from young shoots of C. forrestii 'Sojub', 5.5cm in length occured in $H_3P_4$ enriched with 2.0 mg/L NAA and 1.0 mg/L BA under darkness, but axillary buds were elongated in the medium with 1.0 mg/L NAA and 3.0 mg/L BA under light condition. On the other hand, rhizomes from young shoot of C. forrestii 'Seosinmae' and 'Songmae', 5.5cm and 2.5cm in length respectively were reformed in 2.0 mg/L NAA and 5.0mg/L kinetin under darkness, but multishoot from young shoot were emerged in 2.0mg/L NAA and 3.0mg/L BA.

• Korean journal of food and cookery science
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• v.21 no.2 s.86
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• pp.263-269
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• 2005

Citrus juice, a concentrate manufactured by the Jeju Provincial Corporation, was converted into vinegar orderly by alcohol and acetate fermentation. The juice with 6 folds dilution by distilled water was used as the sole nutrient source through out experiments. Diluted juice contained $12.96^{\circ}Brix$ of total sugar, $0.632\%$ of total acid and $20.23{\mu}g/m{\ell}$ of hesperidin. Naringin was not detected from the juice. Citrus wine having $5.6\~6.3\%$ alcohol was produced from diluted juice by 3 days of fermentation at $28^{\circ}C$. A kind of malomelo yeast CMY-28 was used for wine fermentation. The wine was succeedingly fermented for 8 days at $30^{\circ}C$ after inoculation of seed vinegar which contained active cells of acid producing bacteria CV1. Inoculum size of seed vinegar was controlled to $10\%$(v/v) of citrus wine. The wine converted into vinegar by the fermentation. Citrus vinegar, the final product of fermentation, was colored with very thin radish-yellow and transparent. It's acidity ranged between $5.8\~6.2\%$ as acetic acid. The vinegar got the best score by sensory test among several natural fruit vinegars. It was clear from the results that citrus vinegar in high quality could be produced from concentrated citrus juice, however fermentation conditions should be improved to reduce the amount of reducing alcohol.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.201-208
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• 2017

Recently, the installation of photovoltaic(PV) systems has been increasing due to the worldwide interest in eco-friendly and abundant solar energy. On the other hand, a PV system has approximately 25% power loss while the energy generated from solar cells is transformed to the power coupling point through a power conversion system (DC/AC). If the output voltage of a string in the PV system is lower than the operating range of the inverter when a part of module in the string has a shadow due to weather conditions, the string is not synchronized and the whole efficiency of output power in a PV system may be reduced significantly. Therefore, to overcome this problem, this paper proposes a novel control method to compensate for the lower voltage by introducing a DC/DC voltage regulator for each string in a PV system, which adopts a concept for MPPT (Maximum Power Point Tracking) control function using the P&O algorithm and adopts constant voltage control method used in an existing inverter. This paper also implements a 2kW DC/DC voltage regulator based on the proposed algorithm and performs a variety of scenario-based experiments. From the simulation result, it was confirmed that the operation efficiency in the proposed method is improved compared to the existing method.

• Journal of Nutrition and Health
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• v.5 no.2
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• pp.91-103
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• 1972

Zinc is one of the essential trace elements in the living organism for growth and health. The first identified metalloenzyme, carbonic anhydrase, is a zinc compound and several others have been described since. Among zinc deficiency syndromes in animals porcine parakeratosis has been successfully treated with zinc supplements, and in man a syndrome of anemia, hypogonadism, hepatosplenomegaly, and dwarfism, prevalent in parts of Iran and Egypt, has been ascribed to lack of zinc in the diet. Dietary zinc excess in the rat is manifested by a hypochromic, microcytic anemia, poor growth, reduction in liver catalase and cytochrome oxidase. The present study is an attempt to delineate the changes of tissue contents of trace elements, especially of iron, copper and zinc in liver and kidneys of the rats. Weanling albino rats, weighing 60 to 80gm. were used in this experiments. The rats were housed in cages with aluminum floors and received feed and distilled water ad libitum. Animals were divided into three groups, control, low zinc diet and high zinc diet groups. The high zinc diet group was subdivided into 0.5% Zn and 0.7%Zn groups. The supplementary copper or iron was added to the high dietary zinc groups. The animals were sacrificed and the tissues were washed several times with deionized water. The wet digested samples were analyzed by Hitachi Model 207 atomic absorption spectro-photometer for the determination of iron, copper and zinc in the liver and kidney. Hemoglobin level in the blood was measured by cyanmethemoglobin method. The results of this study are as follows: 1) All rats fed high zinc diets and low zinc diets gained less weight than control. Weight gain was not improved by the supplementary copper or iron and both. 2) Hemoglobin concentration was decreased significantly in the rats fed high zinc diets and less in the low zinc diet. Supplementary copper and iron to the higher zinc diet appeared to give some improvement of anemia. 3) The iron contents of the liver and kidneys were significantly decreased in the high zinc groups and the reduction was more significantly in the rats receiving higher zinc diet (0.7%). The supplementary copper caused a further depression of liver iron. On the other hand, the iron, added to the high zinc diet lessoned the severity of the decrease in liver iron and caused kidney iron to be maintained almost at the level found in the rats fed by zinc and supplementary copper diet. 4) High zinc diets did not change copper content of the liver and kidney. Supplementary copper elevated the concentration in the liver and kidney and added iron had no effect on the accumulation of copper in the liver and kidneys. 5) The high zinc diets caused marked increases of zinc content in the liver and kidney. Supplementary iron to the high zinc diet caused increases of zinc contents of liver and kidneys.

• Journal of KIISE:Software and Applications
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• v.32 no.7
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• pp.663-673
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• 2005

An analysis model for the dynamics information of two-dimensional time-series patterns is described. In the proposed model, two novel transforms that visualize the dynamic characteristics are proposed. The first transform, referred to as speed equalization, reproduces a time-series pattern assuming a constant linear velocity to effectively model the temporal characteristics of the signing process. The second transform, referred to as velocity transform, maps the signal onto a horizontal vs. vertical velocity plane where the variation oi the velocities over time is represented as a visible shape. With the transforms, the dynamic characteristics in the original signing process are reflected in the shape of the transformed patterns. An analysis in the context of these shapes then naturally results in an effective analysis of the dynamic characteristics. The proposed transform technique is applied to an online signature verification problem for evaluation. Experimenting on a large signature database, the performance evaluated in EER(Equal Error Rate) was improved to 1.17$\%$ compared to 1.93$\%$ of the traditional signature verification algorithm in which no transformed patterns are utilized. In the case of skilled forgery experiments, the improvement was more outstanding; it was demonstrated that the parameter set extracted from the transformed patterns was more discriminative in rejecting forgeries