• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.5
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• pp.84-90
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• 2014

The aim of this paper is to investigate the application of solar energy in reducing cabin thermal load. When a vehicle is parked under the sun in summer, the interior temperature can reach up to $70^{\circ}C$ depending on the solar intensity. Solar power, one of the green energies, is used in automobile air conditioning systems, in order to operate the blower. The power supply of a blower's voltage has been used in a solar sunroof experiment. At the climate wind tunnel, cabin temperature changes were conducted with various operating modes of an air handling system and the preventilation parking conditions of several vehicles, outdoors, was also examined. The test results of the solar sunroof, 39.3W power and 14.1% efficiency were obtained. The thermal load behavior was analysed with the air handling system operating mode differently according to the cabin temperature. By simply operating the blower, average cabin temperature decreased between $5^{\circ}C{\sim}10^{\circ}C$ in those vehicles parked outdoors in summer. This reveals that cabin thermal comfort can be improved without consuming the vehicle's extra energy, and that the performance of the air-conditioning system is better than those currently found in vehicles. Moreover, fuel economy will be increased as a result of the reduction in the use of the air-conditioning system, and many other human advantages will be gained. Such advantages include minimized VOCs and a healthy cabin environment.

• The Korean Journal of Applied Statistics
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• v.24 no.3
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• pp.535-546
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• 2011

This study develops statistical models for the binary forecast of Asian dust days over South Korea in the winter season. For this study, we used three kinds of data; the rst one is the observed Asian dust days for a period of 31 years (1980 to 2010) as target values, the second one is four meteorological factors(near surface temperature, precipitation, snowfall, ground wind speed) in the source regions of Asian dust based on the NCEP reanalysis data and the third one is the large-scale climate indices. Four kinds of statistical models(multiple regression models, logistic regression models, decision trees, and support vector machines) are applied and compared based on skill scores(hit rate, probability of detection and false alarm rate).

• Journal of Environmental Science International
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• v.17 no.8
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• pp.907-918
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• 2008

In order to monitor the impact of high temperature which is seen frequently with climate change, we investigated the monthly change in globe temperature, air temperature, mean radiant temperature and effective radiant heat flow, because the four well reflect thermal radiation from bio-meteorological aspect. Both globe temperature and air temperature showed an increasing trend every month. Compared to air temperature, globe temperature had a wider range of temperature change and was more influenced by meteorological element such as precipitation. Diurnal trends of air temperature, globe temperature and the difference between their temperature had the lowest value before the sunrise and the highest around $1300{\sim}1500$ LST, showing the typical diurnal trends. Globe temperature and the difference between their temperature had a sharp increase around $1000{\sim}1100$ LST, maintained high value until 1700 LST and then reclined, though varied by month. The difference between globe temperature and air temperature was highly dependent on the amount of precipitation and clouds. The duration in which globe temperature was higher than air temperature was the lowest in July. Therefore the amount of precipitation was the most affecting, followed by the amount of clouds and wind. In order to find out the diurnal trends of temperature in city center and city outskirts, we assumed the roof of a concrete build ing as a city center, and the grass-covered observatory of the Gimhae International Airport as city outskirts. The diurnal trends of temperature in the two sites showed a strong correlation. The highest and lowest temperature also had the same trend.

• Journal of the Korean earth science society
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• v.30 no.5
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• pp.660-670
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• 2009

This study examines the changes of an interdecadal circulation over the Asian continent to find cause of the surface warming in Siberia from 1958 to 2004. According to our study, there is a coherency between a long-term change of sea surface temperature in the Indian Ocean and the rapid increase of air temperature in Siberia since 1976/1977. In this study, we suggest that mean wind field changes induced by the positive sea surface temperature anomalies of the Indian Ocean since 1976/1977 are caused of inter-decadal variations in a large-scale circulation over the Asian continent. It also indicates that the inter-decadal circulation over the Asian continent is accompanied with warm southerly winds near surface, which have significantly contributed to the increase of surface temperature in Siberia. These southerly winds have been one of the most dominant interdecadal variations over the Asian continent since 1976/1977. In addition, we investigated the long-term trend mode of 850 hPa geopotential height data over the Asian continent from the Empirical Orthogonal Function (EOF) analysis for 1958-2004. In result, we found that there was an anomalously high pressure pattern over the Asian continent, it is called 'the Asian High mode'. It is thus suggested that the Asian High mode is another response of interdecadal changes of large-scale circulations over the Asian continent.

• Journal of Environmental Science International
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• v.19 no.7
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• pp.917-929
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• 2010

This paper aims to find out the statistical characteristics of the weather related railroad accidents and incidents. Data from Korea Railroad Operation Information System(KROIS) and Korea Railroad Accidents reports during 1996-2008 were used to investigate the occurrence frequency of railroad accidents and operation obstacles and their association with weather phenomena. The results are as follows; The occurrence frequency of railroad accidents and operation obstacles decrease gradually, and most of railroad accidents is a railroad traffic accidents. The amount of damages by a railroad weather-related accidents is higher than those of the railroad accidents and operation obstacles. It was also found that weather events influencing the railroad weather-related accidents and incidents are rainfall, snowfall, lightning, winds. And they caused a railroad weather-related accidents and incidents, such as railway obstruction, signal failure, and power supply failure. Therefore we need research about threshold review and a quantitative and qualitative analysis of a railroad weather-related accidents and incidents according to climate change.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.17 no.2
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• pp.105-108
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• 1981

The oceanic effect on the climate of the southern coast of Korea was analysed based on the sea surface temperature and in order to study relationships between the fluctuation of the sea surface temperature and that of climatic elements. Meteolorogical data from 1960 to 1979 were used. In the year when difference between the air and water temperature was maximum, the air temperature in southern coast was higher than normal year. A fluctuation of the sea surface temperature plays an important influence to determine the variation of the air temperature in the coastal area. Humidity of the coastal climate depends upon the oceanic effect in summer, but not in winter. This results may be due to prevailing wind effect. The oceanic effect on the precipitation in the coastal area is not found.

• Journal of agriculture & life science
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• v.45 no.4
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• pp.29-35
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• 2011

A forest fire was one of the huge disasters and damaged human lifes and a properties. Therefore, many countries operated forest fire forecasting systems which developed from forest fire records, weather data, fuel models and etc. And many countries also estimated future state of forest fire using a long-term climate forecasting like GCMs and prepared resources for future huge disasters. In this study, we analyzed relationships between forest fire occurrence and meteorological factors (the minimum temperature ($^{\circ}C$), the relative humidity (%), the precipitation (mm), the duration of sunshine (hour) and etc.) for developing a estimating tools, which could forecast forest fire regime under future climate change condition. Results showed that forest fires in this area were mainly occurred when the maximum temperature was $10{\sim}200^{\circ}C$, when the relative humidity was 40~60%, and when the average wind speed was under 2m/s. And forest fires mainly occurred at 2~3 day after rainfall.

• Journal of Climate Change Research
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• v.8 no.2
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• pp.125-143
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• 2017

This study is conducted to estimate potential evapotranspiration of 10 weather observing systems in Andong Dam watershed with FAO56 Penman-Monteith (FAO56 PM) methodology using the meteorological data from 2013 to 2014. Also, assuming that there is no solar radiation data, humidity data or wind speed data, the potential evapotranspiration was estimated by FAO56 PM and the results were evaluated to discuss whether the methodology is applicable when meteorological dataset is not available. Then, the potential evapotranspiration was estimated with Hargreaves method and compared with the potential evapotranspiration estimated by FAO56 PM only with the temperature dataset. As to compare the potential evapotranspiration estimated from the complete meteorological dataset and that estimated from limited dataset, statistical analysis was performed using the Root Mean Square Error (RMSE), the Mean Bias Error (MBE), the Mean Absolute Error (MAE) and the coefficient of determination ($R^2$). Also the Inverse Distance Weighted (IDW) method was performed to conduct spatial analysis. From the result, even when the meteorological data is limited, FAO56 PM showed relatively high accuracy in calculating potential evapotranspiration by estimating the meteorological data.

• Journal of Climate Change Research
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• v.9 no.3
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• pp.209-221
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• 2018

The characteristics of heat wave events in Seoul are analyzed using weather station data from Korea Meteorological Administration (KMA) and European Centre for Medium-Range Weather Forecast (ECMWF) ERA-Interim reanalysis data from 1979 to 2016. Heat waves are defined as events in the upper 10th percentile of the daily maximum temperatures. The associated synoptic weather patterns are then classified into six clusters through Self-Organizing Map (SOM) analysis for sea-level pressure anomalies in East Asia. Cluster 1 shows an anti-cyclonic circulation and weak troughs in southeast and west of Korea, respectively. This synoptic pattern leads to southeasterly winds that advect warm and moist air to the Korean Peninsula. Both clusters 2 and 3 are associated with southerly winds formed by an anti-cyclonic circulation over the east of Korea and cyclonic circulation over the west of Korea. Cluster 4 shows a stagnant weather pattern with weak winds and strong insolation. Clusters 5 and 6 are associated with F?hn wind resulting from an anti-cyclonic circulation in the north of the Korean Peninsula. In terms of long-term variations, event frequencies of clusters 4 and 5 show increasing and decreasing trends, respectively. However, other clusters do not show any long-term trends, indicating that the mechanisms that drive heat wave events in Seoul have remained constant over the last four decades.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.4
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• pp.351-364
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• 2021

In this study, the vertical distribution of giant jellyfish analyzed echo counting method and such survey methods as sighting and trawl were used to compare its density estimates. In May and July 2021, surveys were conducted in the East China Sea and the coastal waters of Korea. As a result, Nemopilema nomurai were evenly distributed in all water layers in East China Sea in May and July. When considered the correlation by each survey methods, it is possible to identify jellyfish in the surface area by sighting method and using sampling net; however, it has a low correlation with acoustic estimates due to marine environmental factor such as weather condition, wind and atmospheric pressure. Therefore, the result can be utilized by basic data when estimating jellyfish's distribution patterns and density estimates from each survey methods hereafter.