• Journal of Korea Water Resources Association
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• v.45 no.10
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• pp.983-995
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• 2012

In this study, it was intended to analyze the spatio-temporal distribution of historical drought events occurred in Korea by way of drought frequency analysis using SPI (Standardized Precipitation Index), and Drought spell was executed to estimate drought frequency as per drought severity and regions. Also, SDF (severity-duration-frequency) curves were prepared per each weather stations to estimate spatial distribution characteristics for the severe drought areas of Korea, and Potential Drought Hazard Map was prepared based on the derived SDF curves. Drought frequency analysis per drought stage revealed that severe drought as well as extreme drought frequency were prominently high at Geum River, Nakdong River, and Seomjin River basin as can be seen from SDF curves, and drought severity was found as severer per each drought return period in the data located at Geum River, Nakdong River, and Seomjin River basins as compared with that of Seoul weather station at Han River basin. In the Potential Drought Hazard Map, it showed that Geum River, Seomjin River, and Yeongsan River basins were drought vulnerable areas as compared to upper streams of Nakdong River basin and Han River basin, and showed similar result in drought frequency per drought stage. Drought was occurred frequently during spring seasons with tendency of frequent short drought spell as indicated in Potential Drought Hazard Map of different season.

• Journal of Korea Multimedia Society
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• v.13 no.12
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• pp.1739-1747
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• 2010

The damage of natural disasters has occurred on huge scale more frequently than before. The damage caused by the disasters are summarized and are analyzed, and are managed as a very general type of documentation, not showing the position of previous damage records and related information such as weather, facilities of CCTV, hospitals, and gas station on the maps. Therefore, it needs to provide map-based searching systems considering damaged area as well as search key-words. This paper focuses on the development of a search system based on the map to manage previous disaster records and related information each disaster using spatial databases. This system consists of three modules, which are databases to store disaster data, the SQL procedure-based search module to extract needed information from the constructed databases, and the map module to express the search results on the map. This paper will contribute to provide framework of a system development for managing the disaster information according to each year and disaster based on the maps and to be utilized as the basic framework in developing damage prediction and prevention systems for disasters in future.

• Atmosphere
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• v.26 no.1
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• pp.111-126
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• 2016

In the numerical weather model, surface properties can be defined by various parameters such as terrain height, landuse, surface albedo, soil moisture, surface emissivity, roughness length and so on. And these parameters need to be improved in the Seoul metropolitan area that established high-rise and complex buildings by urbanization at a recent time. The surface roughness length map is developed from digital elevation model (DEM) and it is implemented to the high-resolution numerical weather (WISE-WRF) model. Simulated results from WISE-WRF model are analyzed the relationship between meteorological variables to changes in the surface roughness length. Friction speed and wind speed are improved with various surface roughness in urban, these variables affected to temperature and relative humidity and hence the surface roughness length will affect to the precipitation and Planetary Boundary Layer (PBL) height. When surface variables by the WISE-WRF model are validated with Automatic Weather System (AWS) observations, NEW experiment is able to simulate more accurate than ORG experiment in temperature and wind speed. Especially, wind speed is overestimated over $2.5m\;s^{-1}$ on some AWS stations in Seoul and surrounding area but it improved with positive correlation and Root Mean Square Error (RMSE) below $2.5m\;s^{-1}$ in whole area. There are close relationship between surface roughness length and wind speed, and the change of surface variables lead to the change of location and duration of precipitation. As a result, the accuracy of WISE-WRF model is improved with the new surface roughness length retrieved from DEM, and its surface roughness length is important role in the high-resolution WISE-WRF model. By the way, the result in this study need various validation from retrieved the surface roughness length to numerical weather model simulations with observation data.

• Journal of Advanced Navigation Technology
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• v.28 no.4
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• pp.393-399
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• 2024

The digital map computer for advanced air vehicles (AAV) must be high-performance, lightweight, portable, and modular. It should receive data on terrain, weather, and obstacles from external modules to display digital maps accurately. This necessitates robust communication capabilities with external devices via an Ethernet interface and the ability to output digital map visuals clearly through an high-defintion multimedia Interface (HDMI) or digital visual interface (DVI) interface. This paper presents the design of both hardware and software architecture that fulfills these critical requirements for an AAV digital map system. Additionally, it establishes the minimum specifications needed and verifies the suitability of the designed digital map computer through rigorous performance measurements and testing. By ensuring these standards, the digital map computer can reliably support the complex navigational needs of AAV, enhancing operational efficiency and safety.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1142-1146
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• 2009

A rainfall simulation and forecasting technique that can generate daily rainfall sequences conditional on multi-model ensemble GCMs is developed and applied to data in Korea for the major rainy season. The GCM forecasts are provided by APEC climate center. A Weather State Based Downscaling Model (WSDM) is used to map teleconnections from ocean-atmosphere data or key state variables from numerical integrations of Ocean-Atmosphere General Circulation Models to simulate daily sequences at multiple rain gauges. The method presented is general and is applied to the wet season which is JJA(June-July-August) data in Korea. The sequences of weather states identified by the EM algorithm are shown to correspond to dominant synoptic-scale features of rainfall generating mechanisms. Application of the methodology to seasonal rainfall forecasts using empirical teleconnections and GCM derived climate forecast are discussed.

• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.6
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• pp.1-9
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• 2009

Watershed topographical data is essential for the management for water resources and watershed management in terms of hydrology analysis. Collecting watershed topographical and meteorological data is the first step for simulating hydrological models and calculating hydrological components. This study describes a specialized Web-based Geographic Information Systems, Soil Water Assessment Tool model data generation system, which was developed to support SWAT model operation using Web-GIS capability for map browsing, online watershed delineation and topographical and meteorological data extraction. This system tested its operability extracting watershed topographical and meteorological data in real time and the extracted spatial and weather data were seamlessly imported to ArcSWAT system demonstrating its usability. The Web-GIS would be useful to users who are willing to operate SWAT models for the various watershed management purposes in terms of spatial and weather preparing.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.3
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• pp.261-269
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• 1989

Agricultural activities in Chejudo require more specialized weather services in this region. The meteorological information available from the Korea Meteorological Service (KMS) is limited in its areal coverage because the KMS stations are located along the narrow band of coastal area. topoclimatological technique which makes use of empirical relationships between the topography and the weather can be applied to produce reasonable estimates of the climatic variables such as air temperature and precipitation over remote land area where routine observations are rare. Presentation of these estimates in a from of fine-mesh grid map can also be helpful to upgrade the quality of weather services in this region. Altitude values of the 250 m grid points were read from a 1: 25000 topographic map and the mean altitude, the mean slope, and the aspect of the slope were determined for each 1 km$^2$ land area from these altitude data. Daily minimum air temperature data were collected from 18 points in Chejudo during the winter period from November 1987 to February 1988. The data were grouped into 3 sets based on synoptic pressure pattern. Departures from the KMS observations were regressed to the topographical variables to delineate empirical relationships between the local minimum temperature under specific pressure patterns and the site topography. The selected regression equations were used to calculate the daily minimum temperature for each 1 km$^2$ land area under the specific pressure patterns. The outputs were presented in a fine-mesh grid map with a 6-level contour capability.

• Journal of the Korean Society for Marine Environment & Energy
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• v.6 no.4
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• pp.3-12
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• 2003

Due to the high demand on energy resources accompanied by continuing industrialization and urbanization, the world marine transportation of crude and product oils is being gradually increased. In Korea, we are exposed to the large-scale marine oil spill accidents because a very large oil tanker of 300,000 tonnage must enter Korean Ports every day to meet the domestic demand on oils. Although we are exerting our strength to reduce the probability of marine oil pollution accidents, a unrestorable oil spill is to occur owing to human errors, severe weather conditions, or combined causes. Thus, area contingency plan equipped with appropriate management system for response and restoration for the worst case discharge scenario must be entirely prepared to protect mine environments and coastal resources. In particular, we are focusing on the Environmental Sensitivity Index Map(ESI Map) to reduce the environmental consequences of both spills and clean-up efforts by specifying protection Priorities in advance and identifying in-situ response strategies. In this paper, Korean ESI Map is introduced with brief definition of sensitivity to oiling and main features of the software developed hitherto.

• Journal of Environmental Impact Assessment
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• v.16 no.5
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• pp.373-379
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• 2007

Natural hazards such as typhoon, flood, landslide affect both coastal and inland areas more often according to increasement of severe and unusual weather. To provide adequate coastal disaster mitigation strategies, coastal disaster prevention system using GIS is very useful. Application methods of digital map on this issue was discussed in this study. For developing of coastal disaster prevention system, the data structures related to disaster monitoring is needed to be revised for interdisciplinary framework. To improve the current coastal disaster mapping methods, GIS based new model for coastal disaster mapping was suggested. In this study, coastal GIS showed the attribute data and structures of coastal disaster mapping.

• Magazine of the Korean Society of Agricultural Engineers
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• v.41 no.6
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• pp.33-43
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• 1999

Drought is a serious diaster in agriculutre, especially to upland crops. Hence, the Agricultural Drought Analysis Model (ADAM) that is integratable with GIS was applied to analyae agriculture drought in upland. ADAM is composed of two sub-models , one is a Soil Water Balance Model (SWBM) and the other is a Drougth Analysis Model (DAM) that is based on the Runs theory. The ADAM needs weather data, rainfall data and soil physical characteristics data as input and calculates daily soil moisture contents. GIS was integrated to the ADAM for the calculation of regional soil moisture using digitized landuse map, detaile dsoil map, thiessen network and district boundary . For the agriculutral drought analysis, the ADAM adapt the Runs theory for analyzing drought duration, severity and magnitude . Log-Pearson Type-III probability distribution function and Kolmogorov-Smirnov test were used to test the fitness of good of the model. The integration of ADAM with GIS was successfully implemented and would be operated effectively for the regional drought analysis.