• Korean Journal of Environmental Agriculture
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• v.27 no.2
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• pp.120-132
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• 2008

Remotely sensed images from a satellite can be applied for detecting and quantifying spatial and temporal variations in terms of landuse & landcover, crop growth, and disaster for agricultural applications. The purposes of this study were to analyze topography using DEM(digital elevation model) and classify landuse & landcover into 10 classes-paddy field, dry field, forest, bare land, grass & bush, water body, reclaimed land, salt farm, residence & building, and others-using Landsat TM images in North Korea. Elevation was greater than 1,000 meters in the eastern part of North Korea around Ranggang-do where Kaemagowon was located. Pyeongnam and Hwangnam in the western part of North Korea were low in elevation. Topography of North Korea showed typical 'east-high and west-low' landform characteristics. Landcover classification of North Korea using spectral reflectance of multi-temporal Landsat TM images was performed and the statistics of each landcover by administrative district, slope, and agroclimatic zone were calculated in terms of area. Forest areas accounted for 69.6 percent of the whole area while the areas of dry fields and paddy fields were 15.7 percent and 4.2 percent, respectively. Bare land and water body occupied 6.6 percent and 1.6 percent, respectively. Residence & building reached less than 1 percent of the country. Paddy field areas concentrated in the A slope ranged from 0 to 2 percent(greater than 80 percent). The dry field areas were shown in the A slope the most, followed by D, E, C, B, and F slopes. According to the statistics by agroclimatic zone, paddy and dry fields were mainly distributed in the North plain region(N-6) and North western coastal region(N-7). Forest areas were evenly distributed all over the agroclimatic regions. Periodic landcover analysis of North Korea based on remote sensing technique using satellite imagery can produce spatial and temporal statistics information for future landuse management and planning of North Korea.

• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.3
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• pp.148-156
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• 2011

The purpose of this study is to analyze the patterns of forest fire possibly related with Asian dust event and carry out a correlation analysis between forest fire occurrence and existence or not of the Asian dust event during dry seasons i.e. February to May in 2000 to 2008. To study the correlation of forest fire and Asian dust, we surveyed information of Asian dust observations, forest fire statistics, fire danger rating index, weather data such as temperature, relative humidity and wind speed of the day occurring the forest fire. As a consequence of analysis, the regional frequency of Asian dust was the highest in Gyeonggi and Chungbuk divisions. Frequencies of forest fire occurrence by the Asian dust events were the highest in the day before three days of the Asian dust event. The highest frequent regions of forest fire occurrence were district of boundary line between Gyeonggi and Western of Gangwon, Chungbuk and Gyeonbuk inland. The correlation between forest fire and fire danger rating index showed the high correlation with the day before three days and after three days of the Asian dust event. These correlation coefficients were 0.50038 and 0.53978 to 1% significance level. The result of analysis between the frequency of forest fire occurrence and wind speed had a highly negative relationship at all the Asian dust days, the day before and after three days. The correlation coefficients had been -0.58623 to -0.61245 to 1% significance level. Relative humidity showed a little of negative relationship with forest fire occurrence in -0.2568(p ${\leq}$ 0.01) for the Asian dust day and -0.35309(p ${\leq}$ 0.01) for next three days. Moreover, at the day before three days of Asian dust events, it was -0.23701 to 1% significance level. However, the mean temperature did not correlate with frequency of forest fire occurrence by Asian dust events at all.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.30 no.5
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• pp.223-233
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• 2018

The predictability of winter storm waves using KMA's operational wind forecasts has been studied to predict wind waves and swells in the East coast of Korea using SWAN. The nested model were employed along the East coast of Korea to simulate the wave transformation in the coastal area and wave dissipation term of whitecapping is optimized to improve swell prediction accuracy. In this study, KMA's operational meteorological models (RDAPS and LDAPS) are used as input wind fields. In order to evaluate model accuracy, we also simulate wind waves and swells using ECMWF reanalysis and KIOST WRF wind and they are compared with the KMA's operational wave model and the wave measurement data on the offshore and onshore stations. As a result, it has the lowest RMSE and the highest correlation coefficient in the onshore when the input wind fields are KMA's operational meteorological forecasts. In the offshore, all of the simulate results shows good agreements with similar error statistics. It means that it is very feasible to use SWAN model with the modified whitecapping factor and KMA's operational meteorological forecasts for predicting the wind waves and swells in the East coast of Korea.

• Journal of Korea Water Resources Association
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• v.45 no.10
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• pp.1023-1034
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• 2012

Linear regression technique has been used widely in water resources field as well as various fields such as economics and statistics, and so on. Using fuzzy regression technique, it is possible to quantify uncertainty and reflect them to the regression model. In this study, fuzzy regression model is developed to compute design floods in any place in Pyeongchang River basin. In ungaged basins, it is usually difficult to obtain data required for flood discharge analysis. In this study, basin characteristics elements are analyzed spatially using GIS and the technique of estimating design flood in ungaged mountainous basin is studied based on the result. Fuzzy regression technique is applied to Pyeongchang River basin which has mountainous basin characteristics and well collected rainfall and runoff data through IHP test basin project. Fuzzy design flood estimation equations are developed using the basin characteristics elements for Pyeongchang River basin. The suitability of developed fuzzy equations are examined by comparing the results with design floods computed in 9 locations along the river. Using regional regression method and fuzzy regression analysis, the uncertainties of the design floods occurred from the data monitoring can be quantified.

• Journal of the Korean Geographical Society
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• v.50 no.3
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• pp.355-373
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• 2015

In this study the factors of fire damage are analyzed through previous research reviews. Local environmental factors as well as those factors attributed to fire damage (number of fire events, number of injured, number of death, economic loss) were selected to compose mutual relationship model. In order to verify this relationship model, official statistics concerning fire damage were collected from 228 local governments and compared with results from previous research. As a result of this comparison four dependent variables and 22 independent variables that affect fire damage were analyzed. Independent variables are divided into human vulnerability factors, physical vulnerability factors, economic vulnerability factors, mitigating factors and local characteristics. To analyze a relationship between selected dependent variables and independent variables, we applied a semi-logarithm model and performed regression analysis. Among the 22 independent variables, the number of the weak to disaster, social welfare service workers, workers in manufacturing industry, and the number of workers in restaurants and bars per 10,000 people show the significant correlation with the number of fire incidence. The number of death from fire is significantly related to two variables which are the number of social welfare service workers per 10,000 and the ratio of commercial area. Damage cost is significantly dependent on the property taxes per 10,000 people. These factors were included in the research model as vulnerability factors (human, physical, economic) and mitigating factors and local characteristics, and the validity of research model was verified. The result could contribute to fire-fighting resource allocation in Korea or they can be utilized in establishing fire prevention policy, which will enhance the national level of fire safety.

• Journal of the Korean Society of Radiology
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• v.10 no.1
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• pp.53-58
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• 2016

March 11, 2011 Fukushima nuclear power plant accident has occurred, the last four years, his is the current state of anxiety remains on the consumer. Therefore, 2015 the current progress continues to have continued research for the purpose of resolving the insecurity of fishery in the country. We measured the radiation of the origin of fishery products, by 2015, research was carried out through a number of references to get additional data or studies that influence this to some degree. Create a consumer and one for the seller for the survey to find out the thoughts of both consumers and sellers on fisheries was to create the statistics by direct survey in 2014 year survey meter using PM1405 equipment dynamics of several species of aquatic origin in accordance with the (Taiwan, China, Russia), mackerel, pomfret, hairtail, saury, shrimp, squid measurements of radiation were investigated. The measurement in 2014 was $0.043{\sim}0.073{\mu}Sv/h$. The seller influenced the survey (90%) on fishery products sales, consumer safety, without this fishery (90%), radioactive contamination very high (28%) and the polarization was not as nearly 72%. The study of the stability of the radiation determined by the radiation levels of the aquatic marine products in a comparison the radiation levels result was determined in ICRP below the standard value (1 mSv/y).

• Anxiety and mood
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• v.14 no.1
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• pp.44-52
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• 2018

Objective : The present study had examined the psychiatric symptoms and physical health consequences for the bereaved parents of the high school students who died in the 2014 Sewol ferry accident. Methods : Forty bereaved parents participated in the study. The authors administered self-report questionnaires about the parents' health behaviors and psychiatric symptoms. The authors also conducted laboratory tests to assess the parents' physical health at 18 and 30 months after the accident. Univariate descriptive statistics were performed to report the prevalence and severity of psychiatric symptoms and health-related behaviors. Paired t-test and Mcnemar test were performed to compare the 18-and 30-month findings. Correlation analysis between psychiatric symptoms and laboratory findings were performed to find a relationship between the two variables. Results : At 30 months after the accident, most of the bereaved parents still appeared to suffer from complicated grief (97.5%), post traumatic stress disorder (80%), insomnia (77.5%) and severe depression (62.5%) based on the scores on the Inventory of Complicated Grief (ICG), the PTSD Check List-5 (PCL-5), the Insomnia Severity Index (ISI) and the Patient Health Questionnaire-9 (PHQ-9). One quarter of the bereaved parents reported high-risk drinking, and 47.5% reported increased drinking amount and frequency after the accident. In objective laboratory results, 55% of the bereaved parents were obese as defined by body mass index ${\geq}25$. The parents' mean low-density lipoprotein shows a significant increase over time (118.5 mg/dL at 18 months. vs. 132.5 mg/dL at 30 months. paired t-test t=-4.061, $$p{\leq_-}0.001$$). Total cholesterol and low-density lipoprotein at 30 months after the accident were in clinically borderline high range. In correlation analysis, triglyceride was positively correlated with ISI. Conclusion : The loss of children in the Sewol ferry accident, a disaster caused by human error, continued to have considerable impact on the victims' parents' mental and physical health 18 and 30 months after the accident. A longitudinal study following the parents' physical health would be necessary to investigate the long-term effects of this traumatic experience on physical health.

• Journal of Korea Water Resources Association
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• v.52 no.10
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• pp.753-761
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• 2019

Localized heavy storm is one of the major causes of flood damage in urban regions. According to the recent disaster statistics in South Korea, the frequency of urban flood is increasing more frequently, and the scale is also increasing. However, localized heavy storm is difficult to predict, making it difficult for local government officials to deal with floods. This study aims to construct a Flood risk matrix (FRM) using ensemble weather prediction data and to assess its applicability as a means of reducing damage by securing time for such urban flood response. The FRM is a two-dimensional matrix of potential impacts (X-axis) representing flood risk and likelihood (Y-axis) representing the occurrence probability of dangerous weather events. To this end, a regional FRM was constructed using historical flood damage records and probability precipitation data for basic municipality in Busan and Daegu. Applicability of the regional FRMs was assessed by applying the LENS data of the Korea Meteorological Administration on past heavy rain events. As a result, it was analyzed that the flood risk could be predicted up to 3 days ago, and it would be helpful to reduce the damage by securing the flood response time in practice.

• Journal of the Korean earth science society
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• v.39 no.6
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• pp.533-544
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• 2018

Rainfall is one of the most important meteorological variables in meteorology, agriculture, hydrology, natural disaster, construction, and architecture. Recently, satellite remote sensing is essential to the accurate detection, estimation, and prediction of rainfall. In this study, the accuracy of Integrated Multi-satellite Retrievals for GPM (IMERG) product, a composite rainfall information based on Global Precipitation Measurement (GPM) satellite was evaluated with ground observation data in the inland of Korea. The Automatic Weather Station (AWS)-based rainfall measurement data were used for validation. The IMERG and AWS rainfall data were collocated and compared during one year from January 1, 2016 to December 31, 2016. The coastal regions and islands were also evaluated irrespective of the well-known uncertainty of satellite-based rainfall data. Consequently, the IMERG data showed a high correlation (0.95) and low error statistics of Bias (15.08 mm/mon) and RMSE (30.32 mm/mon) in comparison to AWS observations. In coastal regions and islands, the IMERG data have a high correlation more than 0.7 as well as inland regions, and the reliability of IMERG data was verified as rainfall data.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.869-878
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• 2021

This study is a study on 11-story apartments that increase the event of fires in old apartments where building-related laws and regulations are not retroactively applied. As a result of analyzing the risk of installing fire doors in Improvement Scenario 2-4, assuming that fire doors are installed as basic scenario 1 in the existing situation where fire doors are not installed at the entrance of direct stairs. In basic scenario 1, the visible distance to the entrance of the direct staircase due to the spread of smoke was 260 seconds. Improvement scenarios 3 to 4 with fire doors installed open 300 seconds after the fire was recognized, and when the fire doors were installed at the entrance of the direct stairs, the visibility to the entrance of the statistics team was less than 600 seconds. In this case, the visibility was 600 seconds at the time of installation of the fire door, and scenarios 3 to 4 increased 56.6% compared to scenario 1, lowering the risk of evacuation by more than 50%. In order to eliminate the risk of non-installation of direct statistical groups that increase the risk of smoke spread, building-related laws such as the Fire Fighting Act shall be retroactively applied when installing a direct stairway entrance or balcony folding evacuation system. The improvement caused by the installation of fire doors has numerically proven the necessity of fire doors during evacuation, and the importance of maintaining fire doors can be grasped.