• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2015.08a
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• pp.117-120
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• 2015

• Korean Journal of Agricultural and Forest Meteorology
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• v.4 no.2
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• pp.127-132
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• 2002

All the countries in RA II (Asia Region in WMO) welcome the establishment of a Web site dedicated to agricultural meteorology, because it is believed that the best way to improve and speed up the flow of information is the use of the Internet and the establishment of a Web site. In providing recommendation for the promotion and improvement of the AgroMeteorological service in RA II, a couple of key suggestions were proposed: (a) Exchanges of data and AgroMeteorological knowledge between member countries and between RAs, (b) Exchanges of experts between member countries as a necessary way to share the knowledge, and (c) Joint research between member countries to solve common problems in AgroMeteorological affairs. In order to meet the above requirements for RA II, an AgroMeteorological information network will be the most critical and dynamic aspect in sustainable agriculture in this region. In addition, the establishment of a Core AgroMeteorological station, recommended by CAgM of WMO, will require its own information sharing systems for communication among member countries. Inevitable use of information technologies (IT) such as information networks, databases, simulation models, GIS, and RS for regional impact assessment of environmental change on AgroEcosystem will be enforced. Thus, the regional Internet-based Agrometeorological information network has been in place since 1999, though all contributions to it have been volunteered by individuals, institutes, universities, etc.

• Atmosphere
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• v.28 no.1
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• pp.1-13
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• 2018

Characteristics of wind resources of offshore and coastal regions were compared using wind data obtained from HeMOSU-1 (Herald of Meteorological and Oceanographic Special Unit-1) meteorological mast located at Southwestern Sea, and ground-based LiDAR (Light Detection And Ranging) at Gochang observation site near it. The analysis includes comparison of basic wind statistics such as mean wind speed, wind direction, power law exponent and their temporal variability as well as site assessment items for the wind power plant such as turbulence intensity and wind power density at the two observation sites. It was found that the wind at HeMOSU-1 site has lower diurnal and seasonal variability than that at Gochang site, which lead to smaller turbulence intensity. Overall, the results of the comparative analysis show that the wind resource at HeMOSU-1 site located offshore has more favorable condition for wind power generation than the wind resource at Gochang which shows nature of coastal area.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.1
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• pp.171-192
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• 2017

The change of any element in the network is possible to cause performance degradation of the multicast network. So it is necessary to optimize the topology path through the multicast update strategy, which directly affects the performance and user experience of the overlay multicast. In view of the above, a new multicast tree update strategy based on perturbation theory Musp (Multicast Update Strategy based on Perturbation theory) is proposed, which reduces the data transmission interruption caused by the multicast tree update and improves user experiences. According to the multicast tree's elements performance and the topology structure, the Musp strategy defines the multicast metric matrix and based on the matrix perturbation theory it also defines the multicast fluctuation factor. Besides it also demonstrates the calculability of the multicast fluctuation factor presents the steps of the Musp algorithm and calculates the complexity. The experimental results show that compared with other update strategies, as for the sensitivity of the multicast fluctuation factor's energized multicast tree to the network disturbance, the maximum delay of the Musp update strategy is minimal in the case of the local degradation of network performance.

• The Korean Journal of Applied Statistics
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• v.22 no.4
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• pp.865-877
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• 2009

While characterized initially as an urban-scale pollutant, ozone has increasingly been recognized as a regional and even global-scale phenomenon. The complexity of environmental data dynamics often requires models covering non-linearity. This study deals with modeling ozone with meteorology in Seoul area. The relationships are used to construct a nonlinear regression model relating ozone to meteorology. The model can be used to estimate that part of the trend in ozone levels that cannot be accounted for by trends in meteorology.

• ETRI Journal
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• v.38 no.6
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• pp.1172-1178
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• 2016

The atmospheric meteorology parameters of the earth, such as temperature, pressure, and humidity, strongly influence the propagation of signals in Global Navigation Satellite Systems (GNSSs). The propagation delays associated with GNSS signals can be modeled and explained based on the atmospheric temperature, pressure, and humidity, as well as the locations of the satellites and receivers. In this paper, we propose an optimized and simplified low cost GNSS base weather station that can be used to provide a global estimate of the integrated water vapor value. Our algorithm can be used to measure the zenith tropospheric delay based on the measured propagation delays in the received signals. We also present the results of the data measurements performed at our station located in the Tlemcen region of Algeria.

• Nuclear Engineering and Technology
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• v.14 no.1
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• pp.17-21
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• 1982

In this paper, as a site evaluation technique, SPMF(Site Population-Meteorology Factor) which is modified from SPF(Site Population Factor) of tile USNRC model, is defined from site population and meteorology data in order to consider the radiological impacts to the population at large from the atmospheric dispersion of the radioactive effluents released during routine plant operation as well as accidental conditions. The SPMF model proved its propriety from the comparison of SPMF and SPF for Kori site. The relative suitability of Korean sites to the U.S. sites have been also examined using SPF.

• Atmosphere
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• v.23 no.4
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• pp.389-400
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• 2013

Chugugi and Wootaeck rainfall data of Gyeonggi Province from 1830 to 1893 were restored from the "Gaksadeungnok" that is the government records between the central government and the local during the Joseon Dynasty. The restored data periods were 27, 10, 9 and 14 years for Kwangju, Suwon, Ganghwa and Gaeseong, and the total number of restored data was 655 for the Chugugi and 427 for the Wootaek, respectively. The variation pattern of monthly rainfall by Chugugi was investigated and it showed that the monthly rainfall more than 300 mm was recorded 25 times with 18 times in July, 5 times in August and 3 times in June. The cases of more than 500 mm were also recorded 8 times with the maximum 787 mm at the Kwangju in July 1862, showing the similar pattern to Seoul. The monthly mean rainfall for the Gyeonggi Province were 259 mm in July, 204 mm in August and 121 mm in June, which were about one third of that of Seoul. The correlation analysis between the Chugugi and Wootaek data was carried out to derive the quantitative values of Wootaek observations. It revealed that 1 'Ri' of Wootaek observation was equal to approximately 1 'Chon (Chugugi unit)' or 20 mm, while 1 'Seo' was very variable between 2 and 6 'Boon (Chugugi unit)' with the median value approximately 3 'Boon' or 6 mm. Recalculated Wootaek data showed that the monthly rainfall in July, August, and June were 289 mm, 154 mm, and 124 mm, respectively. Through this study, some features of the rainfall variation pattern during 1830~1893 were figured out, and quantitative interpretation of Wootaek data became possible based on the restored rainfall data from the "Gaksadeungnok". Though many pages of the book have been lost during the last hundreds years, "Gaksadeungnok" is still very meaningful and of practical use, for it contains plenty of the local data throughout the whole country during the latter part of Joseon Dynasty. Therefore, further studies are strongly recommended on the restoration of climate related data and on the climatic tendency of 19th century of Korean peninsular.

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.2
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• pp.171-183
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• 2005

In order to monitor the global terrestrial carbon cycle, NASA (National Aeronautics and Space Administration) provides 8-day GPP images by use of satellite remote-sensing reflectance data from MODIS (Moderate Resolution Imaging Spectroradiometer) at l-km nadir spatial resolution since December, 1999. MODIS GPP algorithm adopts DAO (Data Assimilation Office) meteorological data to calculate daily GPP. By evaluating reliability of DAO data with respect to surface weather station data, we examined the effect of errors from DAO data on MODIS GPP estimation in the Korean Peninsula from 2001 to 2003. Our analyses showed that DAO data underestimated daily average temperature, daily minimum temperature, and daily vapor pressure deficity (VPD), but overestimated daily shortwave radiation during the study period. Each meteorological variable resulted in different spatial patterns of error distribution across the Korean Peninsula. In MODIS GPP estimation, DAO data resulted in overestimation of GPP by $25\%$ for all biome types but up to $40\%$ for forest biomes, the major biome type in the Korean Peninsula. MODIS GPP was more sensitive to errors in solar radiation and VPD than in temperatures. Our results indicate that more reliable gridded meteorological data than DAO data are necessary for satisfactory estimation of MODIS GPP in the Korean Peninsula.

• Journal of the Korean earth science society
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• v.26 no.2
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• pp.129-136
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• 2005

Continued observation of ARGO floats for years(about 4 years) makes the conductivity sensor more vulnerable to fouling by marine life and associated drift in salinity measurements. In this paper, we address this issue by making use of floats deployed in different years. Floats deployed in the East Sea and the Indian Ocean are examined to find out float-to-float match-ups in such a way that an older float pops up simultaneously with a newer deployment (with tolerable space-time difference). A time difference of less than five days and space difference of less than 100km are considered for the match-up data sets. For analysis of the salinity drift under the stable water mass, observations of the floats from deepest water masses have been used. From the cross-check of ARGO floats in the East Sea and the Indian Ocean, it is found that there is a systematic drift in the older float compared to later deployments. All drift results, consistently show negative bias indicating the typical nature of drift from fouled sensors. However, the drift is much less than 0.01, the specified accuracy of ARGO program.