• Journal of Korea Water Resources Association
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• v.52 no.10
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• pp.671-680
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• 2019

Many researches illustrated that the magnitude and frequency of hydrological event would increase in the future due to changes of hydrological cycle components according to climate change. However, few studies performed quantitative analysis and evaluation of future rainfall in North Korea, where the damage caused by extreme precipitation is expected to occur as in South Korea. Therefore, this study predicted the extreme precipitation change of North Korea in the future (2020-2060) compared to the current (1981-2017) using stationary and nonstationary frequency analysis. This study conducted nonstationary frequency analysis considering the external factors (mean precipitation of JFM (Jan.-Mar.), AMJ (Apr.-Jun.), JAS (Jul.-Sept.), OND (Oct.-Dec.)) of the HadGEM2-AO model simulated according to the Representative Concentration Pathway (RCP) climate change scenarios. In order to select external factors that have a similar tendency with extreme rainfall events in North Korea, the maximum annual rainfall data was obtained by using the ensemble empirical mode decomposition (EEMD) method. Correlation analysis was performed between the extracted residue and the external factors. Considering selected external factors, nonstationary GEV model was constructed. In RCP4.5, four of the eight stations tended to decrease in future extreme precipitation compared to the present climate while three stations increased. On the other hand, in RCP8.5, two stations decreased while five stations increased.

• The Korean Journal of Nuclear Medicine
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• v.38 no.1
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• pp.41-51
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• 2004

PURPOSE: Tourette's disorder (TD), which is characterized by multiple waxing and waning motor tics and one or more vocal tics, is known to be associated with abnormalities in the dopaminergic system. To testify our hypothesis that risperidone would improve tic symptoms of TD patients through the change of the dopaminergic system, we measured the dopamine transporter (DAT) densities between drug-naive children with TD and normal children, and investigated the DAT density before and after treatment with risperidone in drug-naive children with TD, using iodine-123 labelled $N-(3-iodopropen-2-yl)-2{\beta}-carbomethoxy-3beta-(4-chlorophenyl)tropane$ ($[^{123}I]IPT$) single photon omission computed tomography (SPECT). MATERIALS and METHODS: $[^{123}I]IPT$ SPECT Imaging and Yale Global Tic Severity Scale-Korean version (YGTSS-K) for assessing the tic symptom severity were carried out before and after treatment with risperidone for 8 weeks in nine drug-naive children with TD. Eleven normal children also underwent SPECT imaging 2 hours after an intravenous administration of $[^{123}I]IPT$. RESULTS: Drug-naive children with TD had a significantly greater increase in the specific/nonspecific DAT binding ratio of both basal ganglia compared with the normal children. However, no significant difference in the specific/nonspecific DAT binding ratio of the basal ganglia before and after treatment with risperidone in children with TD was found, although tic symptoms were significantly improved with risperidone. CONCLUSION: These findings suggest that DAT densities are directly associated with the pathophysiology of TD, however, that the effect of risperidone on tic symptoms in children with TD is not attributed to the change of dopaminergic system.

• Radiation Oncology Journal
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• v.19 no.2
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• pp.136-141
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• 2001

Purpose : To evaluate the significance of serum SCC for the monitoring of treatment response and the early detection of distant metastasis during radiotherapy (RT). Materials and Methods : In 13 patients with histologically proven primary squamous cell carcinoma of uterine cervix, serum SCC values were checked in pre-RT point, weekly during RT, and in post-RT point. Results : In 4 of 13 cases, metastasis appeared at the end of external RT, so that intracavitary radiation couldn't be peformed.01 these 4 cases,3 with elevated pre-RT SCC level, who resulted in lung metastasis on chest PA at the end of external RT showed decreased post-RT SCC value despite of metastasis. Of all 10 cases with elevated pre-RT SCC value (including 3 with metastasis at the end of external RT), SCC value was higher than pre-RT value in 7 at 9 Gy and the difference was statistically significant. At 18 Gy, SCC was higher in 4 and lower in 6 than pre-RT value. After 18 Gy, SCC value decreased continuously to the end of RT in all 10 cases. Conclusion : During RT, SCC value increased initially at 9 Gy. To 18 Gy, SCC value decreased to the nearly same with pre-RT value. After 18 Gy, to the end of RT, SCC value decreased continuously and normalized in completely responded cases. In cases with appearance of lung metastasis, SCC value also decreased with the disappearance of main mass of uterine cervix despite metastasis.

• Korean Journal of Plant Resources
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• v.19 no.5
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• pp.602-605
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• 2006

Effects of Codium fragile ext. on lipid lowering and antioxidant activities were investigated in hyperlipidemic rat. Concentration of FFA and triglyceride in plasma showed a tendency to decrease in Codium fragile ext. groups. Concentration of plasma total cholesterol and LDL-cholesterol in Codium fragile ext. groupsshowed a low values than those of control group. However concentration of HDL-cholesterol showed no significant difference in all treatment groups. Concentration of liver total cholesterol and triglyceride showed a tendence to decrease in Codium fragile ext. groups. Concentration of plasma and liver TBARS showed a low values in Codium fragile ext. groups. The values of GSH-Px activity showed a tendency to increase in the Codium fragile ext. groups, However the values of SOD and CAT activity showed no significant difference in all treatment groups.

• The Korean Journal of Financial Management
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• v.8 no.1
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• pp.139-153
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• 1991

This paper examines the pecuniary effects stemming from insider trading in the equities of firms targeted for acquisition. Illegal exchanges by those having advantageous information are found to result in excessive returns to stockholders of the sought firms. However, unusual market activities are not typical immediately subsequent to the illegal trading date, suggesting that nonpublic information is synthesized by market mechanisms with sufficient speed so that others cannot profit by imitating the better informed traders. The obtained evidence does not support the contention that insider trading on nonpublic information harms the outsider stockholders of involved firms.

• Journal of the Korean Chemical Society
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• v.37 no.12
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• pp.1025-1034
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• 1993

We have measured ${\pi}^*$, $\alpha$ and $\beta$ polarity parameters of 2-propanol / hexane and ethyl acetate / hexane mixed solvents over the entire range of composition. For the ethyl acetate / hexane system, only ${\pi}^*$ and $\beta$ were measured since $\alpha$ of these mixed solvents are defined zero. We have corrected the measured polarity parameters to obtain consistent data with the existing literature data assuming a good linear correlation between the measured and the true values. The variation patterns are consistent with the expected trends based on the chemistry of the solvent components. The general trends of the two solvent systems are summarized as follows. ${\pi}^*$ merely increases as the content of the more polar solvent increases while $\alpha$ and $\beta$ increase with the increase of the content of the more polar solvent, then decrease upon continuing addition of the more polar solvent.

• The Transactions of the Korean Institute of Power Electronics
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• v.9 no.4
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• pp.356-363
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• 2004

This paper presents a precision voltage control technique of a single phase PWM inverter for a constant voltage and constant frequency(CVCF) applications. The proposed control scheme employs an additional phase-locked loop(PLL) compensator which is constructed using the output capacitor voltage and current. The computer simulation and experiment are carried out for the actual single-phase PWM inverter and it is well demonstrated from these results that the steady-state performance and total harmonic distortion(THD) are remarkably improved by employing the proposed technique.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.15-19
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• 1996

A field experiment was conducted to understand effect of nitrogen and potassium fertilizer application on paddy where drought damaged rice plant before panicle stage in 1994. The field located on a terraced position with silt loam texture. The application rates of nitrogen were 30 and 60 kg/ha, and those of potassium were 20 and 40 kg/ha. Rice yield from normally irrigated plot was 5.02 ton/ha, while control plot depended on rainfed was 1.67 ton/ha. The yield from control plot irrigated at panicle stage was 86% of normally irrigated plot. Nitrogen application with irrigation at panicle stage increased yield, significantly, while potassium application showed little effect.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.3
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• pp.280-287
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• 2010

The first Korean satellite launch vehicle, KSLV-I(Korea Space Launch Vehicle-I), was launched for its first flight test on Aug. 25, 2009 from Naro Space Center located in south Jolla province. Because launch vehicles usually fly long range with large amount of propellants aboard, preparation of countermeasures against potential malfunctions during flight is essential in launch operation. In this paper, the flight safety operation, prepared to guarantee flight safety during launch operation of KSLV-I, is presented. Prior to flight test, flight safety analysis is performed to estimate associated risk levels quantitatively, and during flight, flight safety systems are operated to cope with any risky situations. Real-time flight monitoring including computation of instantaneous impact point using tracking data is executed normally and the flight test is completed without activation of flight termination system.

• Korean Journal of Clinical Pharmacy
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• v.16 no.1
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• pp.1-8
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• 2006

Methotrexate(MTX)는 소아 골육종 환자에서 $12g/m^2$의 고용량을 사용하고 있다. 현재, 소아 골육종 환자에서 신기 능에 따른 고용량 MTX의 임상 약동학은 연구되어 있지 않다. 따라서 본 연구에서는 신기능에 따른 MTX 약동학을 이용하여 구내염을 최소화하는 방법을 제시하고자 하였다. 방법: 환자들의 의무기록지를 후향적 방법으로 검토하였다. 한 병원에서 골육종으로 진단받고, 치료 받은 환자들을 대상으로 정상 신기능군과 비정상 신기능군으로 나누었다. 두 군에 MTX 투여 후 혈중 농도를 각각 비교하였고, 최고 혈중농도도 비교하였다. 혈중 농도와 구내염의 관련성, CL, AUC와 구내염의 상관관계를 분석하였다. 각 군의 terminal half-life, CL, Vss의 평균과 mea residence time(MRT)의 평균을 구하였고, 두 군간 각각을 비교하였다 $({\alpha}=0.05)$. 결과: 환자는 6명이었고, 평가 가능한 총 MTX 투여 회수는 34회였다. MTX 투여 후 최고혈중 농도, 24,48 시간의 혈중농도는 통계적으로 유의성 있는 차이가 있었고, 72,96 시간에서의 농도는 두 군간 유의성이 없었다. 각 군에서 혈중농도와 구내염의 상관관계, 그리고 CL, AUC와 구내염의 상관관계는 발견되지 않았다. Vss를 제외한 모든 파라미터들(terminal half-life, CL, MRT)은 통계적으로 유의성 있는 차이가 있었다. 결론: 비정상 신기능 군에서 MTX 투여 시작 후 24, 48 시간에서의 혈중농도가 더 높고, 변동이 심했다. 또한 MTX의 CL는 감소했고, 혈중농도는 증가하였다. 이러한 사실로 MTX 투여 전 후 혈중 크레아티닌이나 또는 크레아티닌 청소율 모니터링이 필요하다는 것을 알 수 있으며, MTX 투여가 끝난 직후 그리고 그 이후 24 시간 간격으로 혈중 농도를 측정해야함을 알 수 있다.