• Atmosphere
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• v.13 no.4
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• pp.57-70
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• 2003

The National Center for Intensive Observation of Severe Weathers (NCIO) as a part of METRI's principal project "Korea Enhanced Observing Period; KEOP" was established at Haenam Weather Observatory in order to effectively monitor and observe heavy rainfall in summer, which is essential for the identification of the structure and evolution mechanism of mesoscale severe weather system. The intensive field-based experiments in 2002 within southwestern Korea toward various meteorological phenomena ranging from heavy rainfall to snowfall were conducted in collaboration with KMA(Korea Meteorological Administration) and universities. In this study, preliminary analysis results using intensive observation data obtained from these experiments are presented together with the introduction of NCIO and its operational structure.

• Journal of Astronomy and Space Sciences
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• v.32 no.3
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• pp.229-235
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• 2015

We estimated the orbit of the Communication, Ocean and Meteorological Satellite (COMS), a Geostationary Earth Orbit (GEO) satellite, through data from actual optical observations using telescopes at the Sobaeksan Optical Astronomy Observatory (SOAO) of the Korea Astronomy and Space Science Institute (KASI), Optical Wide field Patrol (OWL) at KASI, and the Chungbuk National University Observatory (CNUO) from August 1, 2014, to January 13, 2015. The astrometric data of the satellite were extracted from the World Coordinate System (WCS) in the obtained images, and geometrically distorted errors were corrected. To handle the optically observed data, corrections were made for the observation time, light-travel time delay, shutter speed delay, and aberration. For final product, the sequential filter within the Orbit Determination Tool Kit (ODTK) was used for orbit estimation based on the results of optical observation. In addition, a comparative analysis was conducted between the precise orbit from the ephemeris of the COMS maintained by the satellite operator and the results of orbit estimation using optical observation. The orbits estimated in simulation agree with those estimated with actual optical observation data. The error in the results using optical observation data decreased with increasing number of observatories. Our results are useful for optimizing observation data for orbit estimation.

• Journal of the Korean Solar Energy Society
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• v.32 no.2
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• pp.95-104
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• 2012

This study purposed to predict wind energy for small size wind power generators at 50m above the ground in each area using mean wind speed data for 10 minutes collected from 2001 to 2011 by meteorological data in large cities having over 60% of 15 story (50m) or higher apartments including Seoul, Daejeon, Gwangju and Daegu representing the inland region, and Busan, Incheon and Ulsan representing the coastal region. In the results of analysis, we confirmed close agree ment between observatory weather data and probability density distribution obtained using Weibull's parameters, and this suggests that Weibull's parameter is applicable to the estimation of wind energy. Hourly output energy using the mean wind speed for 10 minutes and output energy obtained from Weibull's parameter showed an error less than 5%, and thus it was found that wind energy can be evaluated using Weibull's modulus.

• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.2
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• pp.81-86
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• 2003

The spatial variability of soil heat fluxes in a conifer forest was investigated by meteorological measurement. The maximum daily averages of R $s_{dn}$ and Rn were about 260 W $m^{-2}$ and 180 W $m^{-2}$ . The daily average of G was typically 10% of net radiation during mid-July to mid-August. The measured soil heat flux of $G_{6}$ was suitable to calculate G within 2% error during the study period. A time delay in the maximum nux at a depth of 0.1 m by heat storage was observed. About 10 to 15 W $m^{-2}$ of error can occur, if it is neglected.

• Journal of Environmental Science International
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• v.23 no.10
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• pp.1731-1743
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• 2014

The time variations in relative humidity observed at the Gangjeong (Goryeong) Reservoir in the Nakdong River over a one-year period (September 2012-August 2013) were analyzed with the Bowen ratio. The thermal vertical scale of the reservoir was also evaluated following Yamamoto's method. The study's results showed that the relative humidity at the reservoir was higher than that of the Daegu Meteorological Observatory (inland) all year round. The difference was slightly larger at nighttime (17-20 %) than at daytime (13-15 %) in all seasons except summer. The quantitative order of latent heat flux was summer, spring, autumn, and winter. This finding signifies that the thermal vertical scale of the reservoir corresponds to that of a shallow lake. The Bowen ratio was smallest at midday of the summer season. In other words, the net radiation energy was converted more as latent heat flux than sensible heat flux during a higher temperature period.

• Journal of Sericultural and Entomological Science
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• v.15 no.2
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• pp.55-60
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• 1973

The statistical interpretations are on the correlations and the linear regressions between the various meteorological conditions the branch Pusan-Observatory of the National-Central-Meteorological-Observatory had measured from 1930 to 1962, and the production of silk worm cocon that the Section of Sericulture in the Ministry of Agriculture ＆ Fishery had recorded from 1930 to 1962 in Gyung Sang Nam Do Korea. These were most in proportion to the sun shine time, an inverse proportion to the atmosphere humidity and the lowest temperature, in proportion to the mean temperature, the highest temperature and the amount of the rain fall. The correlations and linear regressions between the various meteorological factors to control the production of the silkworm cocoon of both per a box of the silk worm egg and per 10a of mulberry field was as follows. (1) The production of the spring silk worm cocoon was dicided by the various meteorological factors. 1. This was in proportion to the total sun shine time between 5 and 6 month. r=0.40＊-(0.42$^{**}$) Y=0.0269$\chi$＋6.46-(0.2795$\chi$＋10.25) 2. This was an inverse proportion to the total amount between 5 and 6 month atmosphere humidity. r=-0.49$^{***}$-(-0.40＊) Y=-0.2989$\chi$＋62.77-(0.1474$\chi$＋31.86) 3. This wasin proportion to the total rain fall amount between 6 and 7 month. r=0.47$^{***}$-(0.44$^{***}$) Y=0.0037$\chi$＋16.42-(0.0035$\chi$＋8.35) (2) The production of the autumn silk worm cocoon was decided by the various meteorological factors. 1. This was in proportion to the total sun shine time between 5 and 6 month. r=0.37＊-(0.45$^{***}$) Y=0.0205$\chi$＋5.51-(0.0173$\chi$＋2.41) 2. This was an inverse proportion to the total amount between 5 and 6 month atmosphere humidity. r=-0.41$^{**}$-(-0.42$^{**}$) Y=-0.2085$\chi$＋45.33-(-0.0599$\chi$＋12.17) 3. This was in proportion to the total of rain fall amount of 6 and 7 month. r=0.48$^{***}$-(0.35＊) Y=0.0050$\chi$＋11.97-( ) 4. This was in proportion to the total sun shine time among 3, 4, 5, and 6 month. r=0.51$^{****}$-(0.49$^{***}$) Y=0.0178$\chi$-1.27-(0.0096$\chi$-3.60) 5. This was an inverse proportion to the total amount among 3, 4, 5, and 6 month atmosphere humidity r=-0.41/$^{**}$-(-0.44$^{***}$) Y=-0.0938$\chi$＋40.14-(-0.05693$\chi$＋20.49) 6. This was in proportion to the total of a year sun shine time. r=0.58$^{****}$-(0.43) Y=0.0037$\chi$＋5.35-(0.0015$\chi$＋1.02) (3) The production of the next year spring silk worm cocoon was decided by the this year various meteorological factors. 1. This was in proportion to the total of a year sun shine time. r=0.55$^{****}$-(0.52$^{****}$) Y=0.0034$\chi$＋12.02-(0.0025$\chi$＋3.84).>＋3.84).3.84).>＋3.84).

• Korean Journal of Remote Sensing
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• v.30 no.2
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• pp.259-274
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• 2014

On Aug 18, 2013, Sakurajima volcano in Japan erupted on a relatively large-scale. Geostationary Ocean Color Imager (GOCI) had used to detect volcanic ash in the surrounding area on the next day of this eruption. The geomagnetic variation has been analyzed using geomagnetic data from Cheongyang observatory in Korea and several geomagnetic observatories in Japan. First, we reconstruct geomagnetic data by principal component analysis and conduct semblance analysis by wavelet transform. Secondly, we minimize the error of solar effect by using wavelet based semblance filtering with Kp index. As a result of this study, we could confirm that the geomagnetic variation usually occur at the moment of Sakurajima volcano eruption. However, we cannot rule out the possibilities that it could have been impacted by other factors besides volcanic eruption in other variation's cases. This research is an exceptional study to analyze geomagnetic variation related with abroad volcanic eruption uncommonly in Korea. Moreover, we expect that it can help to develop further study of geomagnetic variation involved in earthquake and volcanic eruption.

• Journal of the Korean earth science society
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• v.42 no.5
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• pp.504-513
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• 2021

Different physical processes, according to the atmospheric boundary layer types, were used in the Local Data Assimilation and Prediction System (LDAPS) of the Unified Model (UM) used by the Korea Meteorological Administration (KMA). Therefore, it is important to verify the atmospheric boundary layer types in the numerical model to improve the accuracy of the models performance. In this study, the atmospheric boundary layer types were verified using observational data. To classify the atmospheric boundary layer types, summer intensive observation data from radiosonde, flux observation instruments, Doppler wind Light Detection and Ranging(LIDAR) and ceilometer were used. A total number of 201 observation data points were analyzed over the course 61 days from June 18 to August 17, 2019. The most frequent types of differences between LDAPS and observed data were type 1 in LDAPS and type 2 in observed(each 53 times). And type 3 difference was observed in LDAPS and type 5 and 6 were observed 24 and 15 times, respectively. It was because of the simulation performance of the Cloud Physics such as that associated with the simulation of decoupled stratocumulus and cumulus cloud. Therefore, to improve the numerical model, cloud physics aspects should be considered in the atmospheric boundary layer type classification.

• Journal of Navigation and Port Research
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• v.46 no.6
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• pp.517-524
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• 2022

This paper analyzes wave measurement using X-band navigation (ship) radar, changes in radar signal due to snowfall and precipitation, and factors that obstruct wave measurement. Data obtained from the radar installed at Sokcho Beach were used, and data from the Korea Meteorological Administration and the Korea Hydrographic and Oceanographic Agency were used for the meteorological data needed for comparative verification. Data from the Korea Meteorological Administration are measured at Sokcho Meteorological Observatory, which is about 7km away from the radar, and data from the Korea Hydrographic and Oceanographic Agency are measured at a buoy about 3km away from the radar. To this point, changes in radar signals due to rainfall or snowfall have been transmitted empirically, and there is no case of an analysis comparing the results to actual weather data. Therefore, in this paper, precipitation, snowfall data, CCTV, and radar signals from the Korea Meteorological Administration were comprehensively analyzed in time series. As a result, it was confirmed that the wave height measured by the radar according to snowfall and rainfall was reduced compared to the actual wave height, and a decrease in the radar signal strength according to the distance was also confirmed. This paper is meaningful in that it comprehensively analyzes the decrease in the signal strength of radar according to snowfall and rainfall.

• Journal of Korea Water Resources Association
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• v.43 no.5
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• pp.471-482
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• 2010

Rainfall events in the hydrologic circulation are closely related with various meteorological factors. Therefore, in this research, correlation relationship was analyzed between sea surface temperature of typical meteorological factor and monthly rainfall on Korean peninsula. The cluster analysis was performed monthly average rainfall data, longitude and latitude observed by rainfall observatory in Korea. Results from cluster analysis using monthly rainfall data in South Korea were divided into 4 regions. The principal components of monthly rainfall data were extracted from rainfall stations separated cluster regions. A correlation analysis was performed with extracted principal components and sea surface temperatures. At the results of correlation analysis, positive correlation coefficients were larger than negative correlation coefficients. In addition, The 3 month of principal components on monthly rainfall predicted by locally weighted polynomial regression using observed data of sea surface temperature where biggest correlation coefficients have. The result of forecasting through the locally weighted polynomial regression was revealed differences in accuracy. But, this methods in the research can be analyzed for forecasting about monthly rainfall data. Therefore, continuous research need through hydrological meteorological factors like a sea surface temperature about forecasting of the rainfall events.