• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.10
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• pp.453-459
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• 2002

This paper proposes an improved algorithm of the daily peak load forecasting for Korean Thanksgiving Day and the Lunar New Year's day. So far, many studies on the short-term load forecasting have been made to improve the accuracy of the load forecasting. However, the large errors of the load forecasting occur i case of Korean Thanksgiving Day and the Lunar New Year's Day. In order to reduce the errors of the load forecasting, the fuzzy linear regression method is introduced and a good selection method of the past load pattern is presented. Test results show that the proposed algorithm improves the accuracy of the load forecasting.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.137-140
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• 2004

Hydraulic structures have been constructed with low cost concrete so as to increase the investment efficiency. As the construction of agricultural irrigation and drainage project is concentrated on off-farming season and come to construction less than 28-day strength in quality control. As we are aware the major thrust construction of short period is now in hydraulic structures rather then the large- scale. This paper will propose the relationship between the 7-day and 28-day compressive strength of concrete be investigated. Test will be carried out on nine different concrete mixes and 180 core drilled form the hydraulic structures with 7-day and 28-day compressive strengths ranging approximately from 24 to 30Mpa.

• Annals of Occupational and Environmental Medicine
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• v.34
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• pp.27.1-27.12
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• 2022

Background: Shift work that interferes with normal sleep patterns, is known to be a cause of sleep disturbance and has been studied through various occupational groups. However, it is not known which shift type is better for sleep health. Methods: This study included 568 firefighters. Sleep quality was evaluated using Pittsburgh Sleep Quality Index. Sleep quality was categorized into 2 groups; good quality (≤ 5 points) and poor quality (≥ 6 points). Demographic variables, depression, anxiety, type of shift, and job were collected by self-reported questionnaires. The χ² test, t-test, and multiple logistic regression analysis were used to evaluate the effect of shift type on the sleep quality of firefighters. Results: Three hundred thirty-seven firefighters (59.3%) have poor sleep quality. Compared to day workers, the odds ratios (ORs) of poor sleep quality were 2.169 (95% confidence interval: 1.137-4.134) in 6-day cycle, 2.161 (1.150-4.062) in 9-day cycle, 1.805 (1.087-2.997) in 21-day cycle, and 1.485 (0.718-3.069) in 3-day cycle. The ORs of poor sleep quality were 1.697(1.021-2.823) in fire suppression and 2.325 (1.213-4.455) in emergency medical service compared to administration. Conclusions: All shift work type except for the 3-day cycle was associated with poor sleep quality compared to day work.

• Journal of fish pathology
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• v.28 no.1
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• pp.37-42
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• 2015

In the present study, we performed a dipping of olive flounder (average length and weight: $20{\pm}2.0cm$, $70{\pm}5.0g$) for a period of three hours a day, over two days, in a melted complex of oxytetracycline (OTC) and neomycin (N), by dissolving 25-10 ppm or 50-20 ppm in water. Subsequently, the remaining antibiotic density in muscle tissue collected from olive flounder was investigated, 1, 5, 14 and 40 days after discontinuation of the medication. 5 fish were used from each group. The standard graph drawn from the results of diluting two standard solutions of OTC and N based on various density levels, showed a relatively straight line with an $R^2$ of 0.9999 and 0.9952, respectively. The recovery rate of OTC was shown to be 90-93% and N, 88-95%. Upon measurement of the remaining antibiotic density in the test group that had been exposed to 25-10 ppm of the complex of OTC and N, $0.97{\pm}0.084{\mu}g/ml$ of OTC and $0.118{\pm}0.079{\mu}g/ml$ N were detected on 1 day of the test. No antibiotic density was detected after day 5 of the test. Regarding the test group that were exposed to 50-20 ppm of the complex of OTC and N, $1.324{\pm}0.062{\mu}g/ml$ of OTC and $0.788{\pm}0.05{\mu}g/ml$ N were detected on day 1 of the test, and no antibiotic density was detected after day 5 of the test.

• Journal of Nutrition and Health
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• v.28 no.7
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• pp.612-619
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• 1995

This study was to investigate the intake of human milk, sodium and potassium of breast-fed infants at 7, 15, 30, 60 and 90 days postpartum. Milk samples were obtained from 20 healthy lactating women living in In-Cheon area. Milk intakes of 20 breastfed infants were determined by the test-weighing method and soldium and potassium contents of human milk were analyzed by Atomic Absorptin Spectrophotometer after Wet-Digestion. Infant milk intakes per day tended to increase during lactation. The mean($\pm$SD) intakes at 7, 15, 30, 60 and 90 day were 460(164), 547(202), 626(199), 718(139) and 688(162)g/day, respectively. The sodium contents decreased significantly from 9.7(1.1)mEq/kg at 7 day to 6.3(1.8)mEq/kg at 90 day(p<0.05). The sodium intakes of infants were 100.8(39.6), 103.3(46.7), 107.2(47.9), 115.5(41.5) and 105.2(41.2)mg/day, respectively and average intake was 107.2(43.9)mg/day. The potassium contents were ranged from 10.5(1.3) to 13.3(2.3) mEq/kg and the potassium intakes of infants were 241.8(11.2), 267.8(98.8), 314.1(98.6), 318.0(66.1) and 276.1(62.6)mg/day, respectively and average intake was 288.3(91.8)mg/day. The mean sodium and potassium intakes of infants between boys and girls were not significantly different at 5% level.

• Journal of Conservation Science
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• v.29 no.3
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• pp.197-207
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• 2013

The gas acceleration test was conducted to identify the deterioration of Korean traditional textiles caused by $NO_2$. Total 20 specimens were prepared using 4 different materials (silk, cotton, ramie, hemp) after dyeing with 5 colors (undyed, red, yellow, blue, black). The specimens were exposed to 0.01, 0.1, 1, 10, 100, and 1000 ppm $NO_2$ gas in the test chamber at $20^{\circ}C$, 50% RH for 1 day. Optical, chemical, and physical evaluation was carried out after the exposure. In the case of Korean traditional textile, color difference increased at 1 ppm/day, $NO_3{^-}$ concentration, carbonyl and C-$NO_2$ functional group increased while pH decreased at 10 ppm/day and tensile strength weakened at 100 ppm/day. when it comes to undyed textile, alteration of color difference on silk and hemp cloth, $NO_3{^-}$ concentration and tensile strength on hemp cloth was remarkable. In addition, color difference on blue and yellow textile, $NO_3{^-}$ concentration increase of yellow textile and tensile strength decrease of hemp cloth & ramie cloth were significant. The results suggest that critical $NO_2$ concentration of optical, chemical, and physical damage on Korean traditional textiles are 1ppm/day, 10 ppm/day, 100 ppm/day respectively.

• YAKHAK HOEJI
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• v.54 no.4
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• pp.295-299
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• 2010

The aim of this study was to develop and validate for determination of alibendol in human plasma by HPLC method. After precipitation of 500 ${\mu}l$ plasma samples by 50% methanol 50 ${\mu}l$ and 60% perchloric acid 30 ${\mu}l$ and the supernatant 50 ${\mu}l$ was injected into HPLC. The assay was performed isocratically using 10 mM potassium phosphate (pH 3.0) and acetonitrile (80 : 20, v/v) as mobile phase. The $C_{18}$ column (particle size $3.5{\mu}m$, $4.6{\times}50$ mm, Zorbax Eclipse) was used as a solid phase. The mobile phase was delivered at a flow-rate of 1.7 ml/min, detection was by ultraviolet absorption at 232 nm and concentrations were calculated on the basis of peak areas. In these conditions, alibendol can be separated from ethylparaben, the internal standard, and endogenous substances. The retention times of alibendol and ethylparaben were just about 2.6 and 3.5 minutes, respectively. This rapid HPLC method was validated by examining the precision and accuracy for inter- and intra-day analysis. The standard curve was linear ($R^2$=1.0000) over the concentration range of 0.05~20 ${\mu}g$/ml. The inter-day relative standard deviation (R.S.D.) and accuracy were 0.2~12.2% and 94.4~101.2% (82.7% at the lower limit of quatitation). The intra-day R.S.D. and accuracy were 0.1~11.8% and 98.8~102.5%, respectively. The method was successfully applied to the determination of alibendol in plasma for a pharmacokinetic study.

• The Journal of Pediatrics of Korean Medicine
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• v.19 no.2
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• pp.99-114
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• 2005

Objectives: This study was aimed to find out the anti-stress and protective-memory effect of Quibitanggagam(QBT) on stress of rats Methods : This experimental study was conducted with elevated plus maze test, passive avoidance test, morris water maze test, and consequently density of AchE reactivity in the CA1 of hippocampus to research the learning and memory of rats affected by restraint stress, Results: Passive avoidance test revealed that time latency of retention test for QBT+Stress group significantly decreased on 2, 3rd day. Morris water maze revealed that acqusitive ability of QBT+Stress group significantly improved on 2, 3rd day and retentive ability of QBT+Stress group was significantly improved on 7th day. Elevated plus maze test revealed that latency in open arm of QBT+Stress group significantly decreased and locomotor activity(number of entered arm) of QBT+Stress group was significantly increased. The values of density of AchE stained nuclei in the CA1 of hippocampus QBT+Stress group was significantly increased compared with SAL+Stress group. Conclusion : According to the above results, it is concluded that QBT will be useful as a remedy against stress disease and improving memory.

• Asian Oncology Nursing
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• v.11 no.1
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• pp.33-40
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• 2011

Purpose: This study compared the effect of two oral care agents on preventing stomatitis and discomfort for acute leukemic patients. Methods: A total of forty patients was enrolled and randomly assigned to sodium bicarbonate or chlorhexidine group. WHO oral toxicity scale was used for measuring stomatitis and Beck's subjective oral discomfort scale for evaluating oral comfort. Data was collected from August 2009 to February 2010. The data was analyzed using Chi-square test, Fisher's exact test, and Mann-Whitney test. Results: Data analyzed was thirty five one. The incidence of stomatitis was 47.4%, 68.8% in sodium bicarbonate and chlohexidine group respectively. The onset of stomatitis was about the 10th and 9th day after chemotherapy initiation, and the duration was 8.0 and 8.67 day respectively. The severity of stomatitis was highest on the 21st day after chemotherapy initiation. There were no statistical differences in the status of stomatitis and the levels of oral comfort during treatment periods. Conclusion: Nurses should routinely assess oral cavity and encourage patients to do oral care actively from second to third week after chemotherapy initiation. Also sodium bicarbonate agent can be recommended to for preventing stomatitis.

• Women's Health Nursing
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• v.13 no.1
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• pp.28-34
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• 2007

Purpose: This study was to examine the effects of auricular acupressure therapy on smoking cessation for female university students. Method. The research design was a nonequivalent control group nonsynchronized design. Subjects were 60 (Experimental: 30, Control: 30) smoking female university students. The measuring tools were the number of cigarettes smoked per day, dependency on nicotine, and need for smoking. Auricular acupressure therapy, an experimental treatment, was applied 3 times a day, 2 days a week, for 2 weeks. Data was collected from March 2006 to October 2006. Data was analyzed using the SPSS PC+ 12 version. Descriptive statistics, independent t-test, $x^2$-test, and Fisher's exact test were used for each aim of this study. Result: The number of cigarettes smoked per day (t=8.63, p=.00), dependency on nicotine (t=18.15, p=.00), and need for smoking (t=14.23, p=.00) significantly decreased in the experimental group by application of auricular acupressure therapy. Conclusion: Auricular acupressure therapy can be a better effective primary nursing intervention on smoking cessation for female university students shown through studies of repetition.