• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.941-942
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• 2006

The Analysis on AVR-MVR conversion trouble for Excitation System AVR-MVR conversion is a very important function to transfer AVR to MVR when the grid has abrupt changes or the control system has some problems. Therefore through studying on AVR-MVR transfer scheme, and problems which might happen when transferring, we would like to enhance the stability of generator and control system.

• Proceedings of the KIEE Conference
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• 2007.04b
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• pp.61-63
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• 2007

In these days there are many troubles - system data error, control malfunctions, cable overheating - in water treatment plant. Specially DAF(Dissolved Air Floation Process) plant has high frequency than previous water treatment process. DAF plant has diverse equipment, nonlinear loads for the precise control. But there is no sufficient overall study about harmonics condition of water treatment plant just taking a following partial action without a fundamental solution. On designing of power system, designer should have regard to harmonics condition, but there is no guide reflected harmonics condition on DAF plant This study says what is the result of guideless design about harmonics. With the result of diagnosis and analysis in DAF plant, economical efficiency and safety of plant will be upgraded in the next design.

• Korean journal of food and cookery science
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• v.20 no.1
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• pp.81-85
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• 2004

This study was conducted to investigate the antioxidant activities of clove extracts in water, methanol and ether. The clove extracts, BHA and ${\alpha}$-tocopherol were added to each oil at a level of 200 ppm. The activities of the substrate oils and controls were tested under autoxidation and thermal oxidation conditions. The degree of the effects of the antioxidant activities under autoxidation condition were in the following order; ether extract 〉 methanol extract 〉BHA 〉 ${\alpha}$-tocopherol 〉 water extract = control group. The induction periods of the control, water, methanol and ether extracts, and BHA and ${\alpha}$-tocopherol were 9.5, 9.6, 10.7 11.8, 10.4 and 9.7 days, respectively. Under thermal oxidation condition, the methanol extract showed stronger antioxidant activity than those of the water and ether extracts. The antioxidant activity of the methanol extract was attributed to ${\alpha}$-tocopherol and BHA.

• Journal of the Korean Institute of Intelligent Systems
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• v.25 no.4
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• pp.369-376
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• 2015

Chemicals are injected in order to remove a variety of organic substances contained in the water purification plant influent. It can be determined with measuring sedimentation turbidity 4~7 hours later, whether the chemical dosage rate is proper or not, which make the real-time feedback control impossible. In addition, manual operation in accordance with the Jar-Test carried out in the laboratory and the operator's experience may cause the experimental and human error by the changes of organic characteristics and water quality. Especially at night ad weekend, the rate have been determined only by the operator judgment owing to environment engineer's absence. Therefore, the decision of optimal chemical dosage rate using proposed intelligent control algorithm is expected to result in real-time injection and cost reduction.

• The Journal of Internal Korean Medicine
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• v.36 no.3
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• pp.284-296
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• 2015

Objectives: The purpose of this study was to examine the effects of Ohmae-hwan (OMH) and Mume Fructus (MF) on inflammatory bowel disease (IBD). Methods: Mice were divided into 4 groups: a normal group, control group, MF group, and OMH group. Three groups, excluding the normal group, were fed a 5% solution of dextran sulfate sodium (DSS) in water for 10 days to induce inflammatory bowel disease. From the fourth day of DSS treatment, the control group was given distilled water only, the MF group was given MF powder in distilled water, and the OMH group was given dried OMH extract powder in distilled water for 7 days. Results: For each animal, changes in body weight, colon length, and component levels in blood and colon tissues after each treatment were noted. The weight in the control group and MF group decreased slightly compared with that in the OMH group, and the colon length in the MF group and OMH group was more than that in the control group. TNF-α and WBC were decreased in both the MF group and the OMH group. RBC was increased in the OMH group, like in the normal group, compared with the control group and MF group. Hb and PLT of each group were not significantly different. Regarding changes in the colon tissues, both the MF group and OMH groups recovered similar to the normal group. Conclusions: Thus, treatment with OMH and MF seems to be effective against inflammatory bowel disease, and OMH is likely to increase body weight and induce RBC recovery better than MF.

• Journal of Oriental Neuropsychiatry
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• v.14 no.1
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• pp.27-44
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• 2003

Objective : The aim of this study was to assess protective effects of Whangryonhaedoktang on the chronic mild stress (CMS) animal model of depression. Method : Male Sprague-Dawley rats were used for this study. The subjects were divided into 3 groups (CMS-drug group: Whangryonhaedoktang was administered during CMS procedure, CMS-vehicle: water was administered during CMS procedure, normal control group: without CMS procedure). After 4 weeks of CMS procedure, Morris water maze (MWM) test and open field test were executed and tyrosine hydroxylase (TH) was measured in ventral tegmental area (VTA) and locus coeruleus (LC) of rat brain. Result : 1. CMS procedure induced defects of spatial learning in early period of MWM test. 2. CMS Whangryonhaedoktang group showed shorter escape latency in comparison with CMS control group in MWM test on the first day of the test. 3. CMS Whangryonhaedoktang group and CMS control group showed no significant difference of activities and emotional behaviors in comparison with normal control group in open field test. 4. CMS Whangryonhaedoktang group showed significant inhibition effects of TH expression in VTA and LC areas in comparison with CMS control group. Conclusion : These results suggest that Whangryonhaedoktang may have inhibition effects to early period defects of spatial learning and protective antidepressant effects in CMS model rats.

• The Journal of Korean Medicine
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• v.28 no.3 s.71
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• pp.183-196
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• 2007

Objective : This study was conducted in order to find the effects of Gammaekdaejo-tang (Ganmaidazao-tang, GDT) by subjecting rats to immobilization stress, thereby inducing depression, anxiety and acquisition-retention defects. Method : Rats treated with normal saline, GDT 200mg/kg and GDT 400mg/kg were subjected to stress by immobilization. Afterwards, behavior changes were observed by elevated plus maze test, acquisition test and retention test in the Morris water maze. The results were obtained by immunohistochemically measuring stress hormone (corticosteroid) levels in the blood. Results and Conclusions : 1. The open arm test in the elevated plus maze showed that compared with the normal group, the time spent decreased in the control group and increased in the GDT 400mg/kg group. 2. The locomotor activity test in the elevated plus maze revealed that the control group showed significant activity decrease compared with the normal group but significant increase in the GDT 400mg/kg group. 3. The acquisition test in the Morris water maze showed that the acquisitive ability of the control group significantly deteriorated on the 3rd and 4th day compared with the normal group, but improved significantly in the GDT 200mg/kg and GDT 400mg/kg groups. 4. The retention test on the 7th day in the Morris water maze revealed that the retentive ability of the control group significantly deteriorated compared with the normal group, but the retentive ability of the GDT 400mg/kg group significantly improved. 5. The blood levels of corticosteroid in the control group increased significantly compared with the normal group but the levels of corticosterone in the blood of the GDT 400mg/kg group significantly decreased.

• Nuclear Engineering and Technology
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• v.52 no.7
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• pp.1429-1435
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• 2020

Applying an accurate parametric prediction model to identify abnormal or false pressurizer water levels (PWLs) is critical to the safe operation of marine pressurized water reactors (PWRs). Recently, deep-learning-based models have proved to be a powerful feature extractor to perform high-accuracy prediction. However, the effectiveness of models still suffers from two issues in PWL prediction: the correlations shifting over time between PWL and other feature parameters, and the example imbalance between fluctuation examples (minority) and stable examples (majority). To address these problems, we propose a cost-sensitive mechanism to facilitate the model to learn the feature representation of later examples and fluctuation examples. By weighting the standard mean square error loss with a cost-sensitive factor, we develop a Cost-Sensitive Long Short-Term Memory (CSLSTM) model to predict the PWL of PWRs. The overall performance of the CSLSTM is assessed by a variety of evaluation metrics with the experimental data collected from a marine PWR simulator. The comparisons with the Long Short-Term Memory (LSTM) model and the Support Vector Regression (SVR) model demonstrate the effectiveness of the CSLSTM.

• Korean journal of food and cookery science
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• v.24 no.6
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• pp.849-855
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• 2008

DPPH radical scavenging activities were 66.80% by hot water extract and 41.86% by 80% methanol extract. Inhibitions of angiotensin I-converting enzyme (ACE) were 91.09% by hot water extract and 75.20% by 80% methanol extract. In this study, Sulgidduk samples were prepared with 1, 3, 5, and 7% concentrated sweet pumpkin powder (CSPP), and a control were examined for quality characteristics such as moisture content, water activity, color, textural characteristics, and sensory qualities, in order to determine the optimal ratio of CSPP in the formulation. The samples containing CSPP exhibited significantly higher moisture content than the control group. Water activity was not significantly different among the Sulgidduk samples. For the color, the control group presented significantly higher lightness as compared to the samples containing CSPP. The samples containing 1 and 3% CSPP had significantly higher greenness than the samples containing 5 and 7% CSPP. Yellowness increased as the level of CSPP content increased. In terms of textural characteristics, hardness, gumminess, and chewiness were highest at the 1% substitution level, while lowest at the 3% level. The CSPP samples presented significantly higher adhesiveness, springiness, and cohesiveness than the control group. In the consumer acceptance and characteristic intensity rating test, the control group showed significantly higher color and flavor as compared to the CSPP samples. Pumpkin flavor, delicious taste, and off-flavor increased with increasing amounts of CSPP. Softness, overall acceptability, and gumminess were not significantly different among the various samples tested. Sweetness was highest at the 5% substitution level, while lowest at the 1% level. In conclusion, the results indicate that substituting $3{\sim}5%$ CSPP to Sulgidduk is optimal, providing good DPPH radical scavenging activity and inhibition of ACE as well as reasonably high overall acceptability.

• Journal of Korean Society on Water Environment
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• v.24 no.6
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• pp.793-800
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• 2008

Recently domestic drinking water industry has recognized membrane-based technology as a promising alternative for water treatment. To ensure successful application of membrane processes, the integrity of membrane systems should be maintained. According to US EPA guidance, the pressure decay test based on the bubble point theory is recommended to detect any membrane defection of which size is close to the smallest diameter of Cryptosporidium oocysts, $3{\mu}m$. Proper implementation of the pressure decay test is greatly affected by initial test pressure, and the interpretation of the test results is associated with upper control limit. This study is conducted to investigate various factors affecting determination of initial test prtessure and upper control limit, including membrane-based parameters such as pore shape correction factor, surface tension and contact angle, and system-based parameters, such as volumetric concentration factor and total volume of system. In this paper, three different hollow fibers were used to perform the pressure decay test. With identical initial test pressure applied, their pressure decay tendency were different from each other. This finding can be explained by the micro-structure disparity of those membranes which is verified by FESEM images of those membranes. More specifically, FESEM images revealed that three hollow fibers have asymmetry, deep finger, shallow finger pore shape, respectively. In addition, sensitivity analysis was conducted on five parameters mentioned above to elucidate their relation to determination of initial test pressure and upper control limit. In case of initial pressure calculation, the pore shape correction factor has the highest value of sensitivity. For upper control limit determination, system factors have greater impact compared to membrane-based parameters.