• Journal of the Korean earth science society
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• v.39 no.3
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• pp.228-240
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• 2018

Solar energy is calculated using meteorological (14 station), ceilometer (2 station) and microwave radiometer (MWR, 7 station)) data observed from the Weather Information Service Engine (WISE) on the Seoul metropolitan area. The cloud optical thickness and the cloud fraction are calculated using the back-scattering coefficient (BSC) of the ceilometer and liquid water path of the MWR. The solar energy on the surface is calculated using solar radiation model with cloud fraction from the ceilometer and the MWR. The estimated solar energy is underestimated compared to observations both at Jungnang and Gwanghwamun stations. In linear regression analysis, the slope is less than 0.8 and the bias is negative which is less than $-20W/m^2$. The estimated solar energy using MWR is more improved (i.e., deterministic coefficient (average $R^2=0.8$) and Root Mean Square Error (average $RMSE=110W/m^2$)) than when using ceilometer. The monthly cloud fraction and solar energy calculated by ceilometer is greater than 0.09 and lower than $50W/m^2$ compared to MWR. While there is a difference depending on the locations, RMSE of estimated solar radiation is large over $50W/m^2$ in July and September compared to other months. As a result, the estimation of a daily accumulated solar radiation shows the highest correlation at Gwanghwamun ($R^2=0.80$, RMSE=2.87 MJ/day) station and the lowest correlation at Gooro ($R^2=0.63$, RMSE=4.77 MJ/day) station.

• Trans-
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• v.1
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• pp.117-139
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• 2016

Radio, the first broadcasting medium in history, is also the first mobile medium that meets the currently mobile ecology based on mobile communications network. As a result, it is easily approachable to consumers, can easily engage individual consumers, and its program contents have a huge appealing power to individual listeners, allowing it to form intimacy with audiences at the closest distance. However, the listening rating of radio has decreased greatly because it has experienced various changes by many other competitive media such as TV and internet and it has been influenced by relative constant hypothesis. Also, radio now faces a bigger competition due to the emergence of smartphone. In this circumstance, radio showed movements to evolve into a digital radio that presents improved sound, strengthened reception power, and increased number of channels, but it suddenly changed to DMB and portable multimedia DMB is having huge problems in its marketability due to smartphone. Yet, the listening rating of analogue radio broadcasting that remained unchanged was 13.99% in 2014, an increase by 47% from 2011, and the percentage of listeners under the age of 18 increased by 2.4 times from 2011 to 2014, which was a unique and interesting phenomenon. Accordingly, this paper compared the characteristics of internet and radio that have the traits of daily life, information, individuality, participatory, adventurousness, alternative media, expertise, and sound media. The paper then examined the listening method of radio, in which the direct groundwave antenna reception through a vehicular device is the most common form during the use of transportation means. Finally, it sought to investigate the future of radio based on the understanding of the increase in radio listening ratings, especially by comparing it to the characteristics of smart generation that focus on smartphone and the internet The study results demonstrated that entertainment and amusements are attempting at changes while they used to be obtained selectively by the smart generation from fragmentary information. In addition, radio is expected to become an influential medium in the future through its advantages of 'selected information' and reliability. However, considering such possibilities, radio needs to build the expertise and reliability of broadcasting contents much more at the same time as its digitalization, and it will be able to have its own competitiveness by focusing on various experiences and cultural exposures.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.1
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• pp.25-34
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• 2015

In this research, we applied a procedure of quality control (QC) to the agro-meteorological data measured at the Suwon weather station of Korea Meteorological Administration (KMA). The QC was conducted through six steps based on the KMA Real-time Quality control system for Meteorological Observation Data (RQMOD) and four steps based on the International Soil Moisture Network (ISMN) QC modules. In addition, we set up our own empirical method to remove erroneous data which could not be filtered by the RQMOD and ISMN methods. After all these QC procedures, a well-refined agro-meteorological dataset was complied at both air and soil temperatures. Our research suggests that soil moisture requires more detailed and reliable grounds to remove doubtful data, especially in winter with its abnormal variations. The raw data and the data after QC are now available at the NCAM website (http://ncam.kr/page/req/agri_weather.php).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.1
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• pp.77-86
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• 1980

Asking to change the cropping patterns to save the labor and capitals in paddy rice cultivation, the study was intended to know the weed problems under the various possible cultural systems; namely, direct seeding (in broadcast and row), machine transplanting and hand transplanting. Under the conditions as weedy check plots, paddy yields were significantly variated among cropping systems, and the functions of panicle No. and spikelet No. to the yield were neglected, among others. However, the yield and yield components were narrowed among cropping systems, and the function of spikelets number per area was comparatively improved to the others.