• Journal of Environmental Science International
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• v.17 no.11
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• pp.1281-1293
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• 2008

This study aims at the estimation of dam failure time and dam failure scenario analysis of and applied to Yeoncheon Dam which was collapsed August 1st 1999, using HEC-HMS, DAMBRK-FLDWAV simulation model. As the result of the rainfall-runoff simulation, the lancet flood amount of the Yeoncheon Dam site was $10,324\;m^3/sec$ and the total outflow was $1,263.90\;million\;m^3$. For the dam failure time estimation, 13 scenarios were assumed including dam failure duration time and starting time, which reviewed to the runoff results. The simulation time was established with 30 minutes intervals between one o'clock to 4 o'clock in the morning on August 1, 1999 for the setup standard for each case of the dam failure time estimation, considering the arrival time of the flood, when the actually measured water level was sharply raising at Jeongok station area of the Yeoncheon Dam downstream, As results, dam failure arrival time could be estimated at 02:45 a.m., August 1st 1999 and duration time could be also 30 minutes. Those results and procedure could suggest how and when dam failure occurs and analyzes.

• The Journal of Information Technology
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• v.1 no.2
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• pp.181-193
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• 1998

The measure of public information flow developed here is the number of order frequency. In the first part of the analysis, I document the general pattern of public information, with an emphasis on the intraday arrival of information. Overall, I find that public information arrival is nonconstant Consistent with earlier studies, I find that information arrival exhibits an inverted U-shape pattern across intraday trading. Over the average trading day, the flow of public information increases throughout the morning hours and then falls over the period, between 3:00 P.M. and 3:05. The second part of my analysis focuse is the relation between the public information variable and measure of intraday order frequency, specifically insignificant effect. According to time flow in the intraday trading, although the number of insignificant effect is increasing moderately, the result is remarkable in light of the aggreate nature of the public information and order frequency variable employed. The foreigner's investor group changes homogenously.

• Journal of Korean Library and Information Science Society
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• v.33 no.3
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• pp.281-310
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• 2002

The aim of this paper is to explore the promotion of reading books at the public school. The promotion of reading books at the school is more important and useful for students than the Educational Information Project, which is setting computers and the Internet at the public school. Because watching TV and navigating the internet without reading books is not good for students to exercise creativity and sound personality. To promote reading books at the school, at first schools need to hire librarian-teachers, and build collection at school libraries as explained. And then schools need to conduct campaigns for promoting reading books, such as reading boots for students, reading books for 10 minutes every morning, and book flood program. In addition, the lesson on reading instruction will be helpful.

• Journal of the Korean Institute of Rural Architecture
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• v.22 no.3
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• pp.33-40
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• 2020

Wood is one of the main materials of wooden building. Hanok also uses wood as its main component. Recently, Hanok continues to be built. Wood is affected by the climatic environment. The growth of decay bacteria is activated at more than 80% relative humidity. The microclimate environment and moisture content were measured for architectural cultural properties that have been maintained for a long time as a wooden building. The method analyzed the measured data by distinguishing between cloudy and sunny days. In the case of the old house, Anchae moisture content was higher than that of Sarangchae. This seems to be due to the narrow front yard or the planting of trees. The microclimate environment inside the house began to decrease in humidity from 8 am. According to the survey data, the relative humidity was less than 80% from 9 am when there was wind around 4-6 am. It appeared an hour earlier than in the absence of wind. As a result, the time interval for dehumidifying of wood was widened. Therefore, the wooden building is open to the front so there is airflow under the eaves during the daytime and wind in the morning appear to be alternatives in order to lower the moisture content.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.4
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• pp.320-328
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• 1993

Gaseous pollutants in Namsan Nos. 1, 2, and 3 tunnels and Pukak tunnel were measured along the road by an air-monitoring van from the evening of February 9 to the morning of February 12 in 1993. Average concentrations of pollutants in Namsan tunnels were 9.2-13.5 ppm CO and 0.037-0.047 ppm SO$_{2}$. Average concentrations of SO$_{2}$ in Pukak tunnel was 0.79 ppm, higher than those in Namsan tunnels, due to the traffic of heavy-duty buses and trucks. The pollutant concentrations in Namsan tunnesl could be explained by emission of passenger cars using unleaded gasolin and LPG taxies. Average concentration of NO$_{x}$ in Namsan tunnels was at least 1.1 ppm, estimated from the emission factor of pasenger cars using unleaded gasoline. Pollutant concentrations in Namsan No. 3 tunnel were higher at the exit because of the piston action of air mass in the tunnel provided by the traffic. Fans installed at Namsan and Pukak tunnes could be useful, but their flushing action of ambient air in the tunnel was not clearly observed.d.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.6
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• pp.503-514
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• 2002

During the past two decades, primary pollutants in the ambient air have been substantially reduced in Korea by aggressive government efforts such as the switchover to clean fuels and equipment of automobiles with a three-way catalytic converter. However, visibility impairment in Seoul and major metropolitan areas has been a stubborn problem. It is apparent that both directly emitted fine particles mainly from vehicles and secondary fine particles from photochemical reactions could contribute to this visibility impairment. In addition, Korea is located downwind of the prevailing westerlies from China and is influenced by the emissions of air pollutants in China. In order to assess this complicated problem of visibility impairment, the visibility trends for the past 17 years observed at more than 60 stations throughout the country were analyzed. The results showed that visibilities were generally the lowest in the winter morning in comparison with those in the summer afternoon as well as the annual average values. It was believed that primary pollution was principally responsible for visibility impairment in most areas. The visibility in the summer afternoon was lower in clean coastal areas along with a high level of relative humidity due to the inflow of moist air accompanied by sea breeze. Although contributions of secondary particles from photochemical reactions and long-range transport of fine particles to the visibility impairment were probable, their certain evidences were not found.

• Archives of Plastic Surgery
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• v.32 no.2
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• pp.250-254
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• 2005

Burns due to epileptic seizures are commonly deep and usually require operative treatment. The purpose of this study is to identify the characteristics of burned epileptic patients that could lead to the development of preventive programs to reduce the incidence of burn injuries. We analyzed epidemiological data for 34 patients acutely burned due to epileptic seizure admitted retrospectively. There were 15 male and 19 female subjects. The age distribution was from 6 years to 70 years with the mean age of 42.7 years. Seizures usually occurred while carrying out daily domestic chores. Scalding burns were the most common(38.2%) and most burns were above deep second degree(94.1%). The most common seizure type was generalized tonic-clonic, followed by absence and complex partial. The seizure mostly occurred in the morning because the therapeutic blood level of antiepileptic drugs was decreased extremely at that time by stopping drug arbitrarily or taking inadequately. So more frequent follow-ups at the neurology outpatient clinics for epileptics should be strictly reinforced to maintain the adequate therapeutic blood levels of antiepileptic drugs and fire protective implements should be prepared in the house.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.1
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• pp.1-11
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• 2003

Temporal and horizontal distributions of surface ozone concentrations covering the Busan metropolitan area were simulated by UAM -V (The Variable grid Urban Airshed Model) that was run with meteorological inputs taken from MM5 for ozone episode day (18 July 1999). UAM-V underestimated the daily maximum ozone con-centration about 14 ppb on average at all monitoring sites within Busan area comparing with observed value. but the correlation between observed and simulated values showed quite significant (R = 0.896, p< 0.01 on average). Higher concentrations of ozone occurred near the city center and industrial areas (western side of city) with high levels of anthropogenic source in the morning, and transport of ozone and its precursors by sea breeze developed in the afternoon contributed to elevated ozone levels in downwind rural areas. Particalarly in slightly downwind area of city center, the highest daily maximum ozone concentration ($\geq$120 ppb) was simulated by UAM-V at 1400 LST. Consequently, local environments including emission distributions and land -sea breeze circulation influenced ozone distributions in the Busan metropolitan area.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.2
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• pp.199-209
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• 1996

The purpose of this study is to evaluate analytical method for the measurement of carbonyl compounds and to apply method to the measurement of indoor and outdoor concentrations of these compounds at public facilities. For sampling, 2.4-dinitrophenylhydrazine (DNPH) coated DNPH-Silica cartridges were uwed in this study. DNPH reacts with carbonyl compounds and forms carbonyl hydrazone, The carbonyl hydarzone was eluted from the cartridge with acetonitrile and analyzed by reverse-phase HPLC with UV detection. Possible interference caused by ozone during sampling was eliminated by using KI trap commected in series with the DNPH-Silica cartridge. A number of experimental studies were undertaken to evaluate and validate the analytical method, including collection efficiency, recovery, repeatability, lower limits of detection, and effect of ozone. Indoor and outdoor measurements of carbonyl compounds were simultaneously carried out at 14 public facilities located in Taegu city and Kyungsan city from June to July, 1995. Except for one or two sites, the indoor concentrations were found to be higher than the outdoor concentrations for carbonyl compounds. And the concentrations of carbonyl compounds measured in the morning and afternoon were showed higher than the concentrations measured in the evening.

• Journal of Pharmaceutical Investigation
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• v.41 no.6
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• pp.371-376
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• 2011

The objective of this work was to investigate the existence of new crystal forms of tulobuterol which is used to prevent morning asthma attacks by ${\beta}_2$ agonist and the transformation of crystal forms. Three crystal forms of tulobuterol have been isolated by recrystallization and Form 2 was transformed to Form 4 at 52% RH and 95% RH and these four crystal forms are characterized by differential scanning calorimetry (DSC), powder X-ray diffractometry (PXRD) and thermogravimetric analysis (TG). The DSC and PXRD patterns of four crystal forms of tulobuterol were different respectively. The dissolution patterns of these three crystal forms of tulobuterol were studied and they showed significant differences in the dissolution rate. After storage of 2 months at 0% RH (silica gel, $20^{\circ}C$), 52% RH (saturated solution of $Na_2Cr_2O_7{\cdot}2H_2O/20^{\circ}C$) and 95% RH (saturated solution of $Na_2HPO_4/20^{\circ}C$), Form 1 and Form 3 were not transformed. But Form 2 was transformed to Form 4 at 52% RH and 95% RH.