• 한국수자원학회논문집
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• 제45권7호
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• pp.631-641
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• 2012

본 연구에서는 지상의 관측 자료와 광역의 정보를 제공하는 수치 예보 모형 자료 및 인공위성 자료를 이용하고 자료와 강수예측치의 물리적 상관 특성을 나타내기 위하여 자료 사이의 비선형 거동을 잘 나타내는 신경망 모형에 적용시켜 단시간 강수 예측을 수행하였다. 이를 위하여 서울지점에 대하여 현재로부터 3시간, 6시간, 9시간, 12시간의 선행시간을 가지는 인공위성자료(MTSAT-1R) 및 수치 예보 모형 자료(RDAPS, Regional Data Assimilation and Prediction System)와 실시간 전송되는 자동 기상 관측 시스템(AWS, Automatic Weather System)의 관측치를 신경망 모형의 입력 자료로 하여 3시간, 6시간, 9시간, 12시간의 선행시간을 가지는 자료로 강수를 예측 할 수 있는 강수 예측 모형을 개발하였다. 장마와 태풍과 같이 전선형강수와 선풍형강수 등 강수 양상의 차이를 고려하기 위하여 6월, 7월과 8월, 9월 자료를 구분하여 신경망을 구축하였으며, 자료가용성에 기초하여 2006년에서 2008년 기간 동안에 대하여 모형을 학습하고 2009년에 대하여 모형의 적용성을 검증한 결과, 단시간 강수예측에 대한 모형의 적용 가능성을 보여주었으나 다양한 광역 자료와 인공신경망을 사용함에도 불구하고 단시간 강수예측의 정량적 정도향상을 위한 여지가 많음을 보여준다.

• 환경영향평가
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• 제22권1호
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• pp.19-26
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• 2013

The propose of this study is to analyze the optimum spatial resolution of the urban spatial thermal environment structure and to evaluate of the possibility detection using aerial photographs and thermal satellite images. The proper techniques of the optimum spatial resolution for the urban spatial thermal environment structure were analyzed. Thermal infrared satellite image of Seoul city were used for the change rate of surface temperature variation and suggested to the spatial extent and effects of urban surface characteristics and spatial data was interpreted as regions. To extract the surface temperature, Landsat thermal infrared satellite image compared with an automatic weather station data and in the field of the measured temperature and surface temperature by thermal environment affects, the spatial domain has been verified. The surface temperature of the satellite images to extract after adjusting surface temperature isotherms were constructed. The changes in surface temperature from 2008 to 2012 the average surface temperature observation images of changing areas were divided into space. The results of this study are as follows: Through analysis of satellite imagery, Seoul city surface temperature change due to extraction comfort indices were classified into four grades. The comfort index indicative of the temperature of Gangnam-gu, $23.7{\sim}27.2(^{\circ}C)$ range and Songpagu, a $22.7{\sim}30.6(^{\circ}C)$ respectively, the surface temperature of Yeouido $25.8{\sim}32.6(^{\circ}C)$ were in the range.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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• pp.227-230
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• 1999

Surface solar radiation over the sea is estimated using Visible and Infrared Spin Scan Radiometer data onbord Geostationary Meteorological Satellite(GMS) 5 for January, 1997 to December 1997 in clear and cloudy conditions. The hourly insolation is estimated with a spatial resolution of 5$\times$ 5 km grid. The island pyranometer belonging to the Japan Meteorological Agency is used for validation of the estimated insolation. It is shown that the estimated hourly insolation has RMSE(root mean square) error of 104 W/$m^2$. The variability of the hourly solar radiation was investigated on 3 areas over seas around Korean Peninsula. The solar radiation of East Sea is similar to Yellow Sea. The maximum value of solar radiation is on June of year. The maximum value in south sea is on August because weather is poor by low pressure and front in June

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.479-484
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• 2007

Recently China has carried out a successful anti-satellite missile test at more than 850km altitude January 11 destroying an aging Chinese weather satellite target with a kinetic kill vehicle launched on board a ballistic missile. Korea has developed scientific and commercial satellites and sounding rockets from 1990s. As the fear of the militarisation of space becomes the reality, we need to consider the safety of our space assets from the perspectives of design, operation, and policy. In this paper we study on the general meanings and impacts of Chinese anti-satellite missile test and the measure to protect our space assets from the points of the design, operation and policy.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.660-663
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• 2006

Rainfall estimation is important to weather forecast, flood control, hydrological plan. The empirical and statistical methods by measured data(surface rain gauge, rainfall radar, Satellite) is commonly used for rainfall estimation. In this study, the rainfall intensity for East Asia region was estimated using the empirical relationship between SSM/I data of DMSP satellite and brightness temperature of GEOS-9(10.7${\mu}m$) with cloud types(ISCCP and MSG classification). And the empirical formula for rainfall estimation was produced by PMM (Probability Matching Method).

• 대한원격탐사학회지
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• 제16권2호
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• pp.157-175
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• 2000

A synthetic aperture radar (SAR) system is able to provide all-weather, day-and- night superior imaging capability of the earth surface, and thus is extremely useful in surveillance for both civil and military applications. In this paper, the X-band high resolution spaceborne SAR system design is demonstrated with the key design performance for a given mission and system requirements characterized by the small satellite system. The SAR multi-mode imaging technique is presented with a critical parameter assessment, and the standard mode results are analyzed in terms of the image quality performances. In line with the system requirement X-band SAR payload and ground reception/processing subsystems are designed and the major design results are presented with the key performance characteristics. This small satellite SAR system shows the wide range of imaging capability with high resolution, and proves to be an effective surveillance systems in the light weight, high performance and cost-effective points of view.

• 한국대기환경학회지
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• 제32권1호
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• pp.46-56
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• 2016

In order to analyze the surface temperature in accordance with the surface material, surface temperatures between Thermal InfraRed Image (TIRI) and Landsat 8 satellite observed at the commercial area (Gwanghwamun) and residential area (Jungnang) are compared. The surface temperature from TIRI had applied atmospheric correction and compared with that from Landsat 8. The surface temperatures from Landsat 8 at Gwanghwamun and Jungnang are underestimated in comparison with that from TIRI. The difference of surface temperature between the two methods is greater in summer than in winter. When the analysis area was divided into detailed regions, depending on the material and the position of the surface, correlation of surface temperature between TIRI with Landsat 8 is as low as 0.29 (Gwanghwamun) and 0.18 (Jungnang), respectively. The results were caused from the resolution difference between the two methods. While the surface temperatures of each zone from Landsat 8 were observed almost constant, high-resolution TIRI observed relatively precise surface temperatures. When the each area was averaged as one space, correlation of surface temperature between TIRIs and Landsat 8 is more than 0.95. The spatially averaged surface temperature is higher at Jungnang, representing residential areas, than at Gwanghwamun, representing commercial areas. As a result, the observation of high resolution is required in order to observe the precise surface temperature. This is because it appears that the spatial distribution of the various surface temperature in the range of micro-scale according to the conditions of the ground surface.

• 한국지구과학회지
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• 제29권7호
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• pp.567-578
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• 2008

온대저기압화는 중위도 기압계에 큰 영향을 주고 때로는 악기상의 원인이 되기도 한다. 그러나 온대저기압화에 대한 예보와 연구 양쪽 모두 많은 과제가 남아있다. 왜냐하면 태풍으로부터 변질된 온대저기압 자체의 모호한 형태 때문이다. 또한, 온대저기압화의 정의가 예보나 연구 양쪽 모두 만족시켜줄 만큼 정확하지도 않다 따라서 기상청은 2007 년에 "온대저기압화 현엽매뉴얼"을 개발하여 온대저기압화의 일련의 과정과 구조 변화 진단에 사용하였다. 이 매뉴얼에서는 1단계 최대풍속과 해수면온도, 2단계 위성영상, 3단계 단열선도, 그리고 최종단계인 4단계에서 지상일기도를 분석하였다. 이 현업매뉴얼은 온대저기압화가 일어날 때 구조변화의 이해와 감시에 도움이 될 것이다.

• 한국농공학회논문집
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• 제62권1호
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• pp.83-93
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• 2020

East Asia, which includes China, Japan, Korea, and Mongolia, is highly impacted by hydroclimate extremes such drought, flood, and typhoon recent year. In 2017, more than 18.5 million hectares of crops have been damaged in China, and Korea has suffered economic losses as a result of severe drought. Satellite-derived rainfall products are becoming more accurate as space and time resolution become increasingly higher, and provide an alternative means of estimating ground-based rainfall. In this study, we verified the availability of rainfall products by comparing widely used satellite images such as Climate Hazards Groups InfraRed Precipitation with Station (CHIRPS), Global Precipitation Climatology Centre (GPCC), and Precipitation Estimation From Remotely Sensed Information Using Artificial Neural Networks-Climate Data Record (PERSIANN-CDR) with ground stations in East Asia. Also, the satellite-based rainfall products were used to calculate the Standardized Precipitation Index (SPI). The temporal resolution is based on monthly images and compared with the past 30 years data from 1989 to 2018. The comparison between rainfall data based on each satellite image products and the data from weather station-based weather data was shown by the coefficient of determination and showed more than 0.9. Each satellite-based rainfall data was used for each grid and applied to East Asia and South Korea. As a result of SPI analysis, the RMSE values of CHIRPS were 0.57, 0.53 and 0.47, and the MAE values of 0.46, 0.43 and 0.37 were better than other satellite products. This satellite-derived rainfall estimates offers important advantages in terms of spatial coverage, timeliness and cost efficiency compared to analysis for drought assessment with ground stations.

• 한국산학기술학회논문지
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• 제20권1호
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• pp.434-439
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• 2019

최근 지구온난화로 인한 기상이변, 도시화로 인한 도심의 열섬현상 등으로 도시 온도변화 및 지표면 온도 변화에 대한 관심이 증대되고 있다. 우리나라에서는 1904년부터 현재까지 기온, 강수량 등 기상 데이터를 수집하고 있다. 최근에는 종관기상관측장비(ASOS; Automated Surface Observing System) 96개소, 방재기상관측장비(AWS) 494개소의 지상기상관측망을 운영하고 있다. 그러나 지상관측망의 경우 각 설치 지점에 대한 점 데이터를 제공하고 있으므로, 측정 지점을 제외한 곳의 지상기상 데이터는 보간법을 통해 예측하고 있는 상황이다. 이에 본 연구에서는 지상의 지표면 온도 측정의 해상도를 향상시키기 위해 위성영상을 이용한 지표면 온도를 산출하고, 그 활용 가능성을 분석하고자 하였다. 이를 위해 서울특별시를 대상으로 Landsat 8 OLI TIRS의 위성영상을 계절별로 획득하고, 열적외 밴드에 NASA식을 적용하여 지표면 온도로 변환하였다. 지상의 측정 자료는 AWS를 통해 측정한 기온 데이터를 활용하였다. AWS 기온 데이터는 관측소 기반의 점 데이터이므로, Landsat 영상과의 비교를 위해 크리깅 보간법으로 보간을 수행하였다. 위성영상기반의 지표면 온도와 AWS 기온 데이터를 비교한 결과 계절에 따른 온도차는 RMSE값을 바탕으로 가을, 겨울, 여름, 봄의 순서로 Landsat 위성영상의 적용 가능성을 판단할 수 있었으며, 위성영상의 시기별 평균온도와 AWS 온도 사이에는 최대 평균 $2.11^{\circ}C$이내, 최대 RMSE ${\pm}3.84^{\circ}C$인 것을 감안하면 정확도 향상을 위해 NASA식에 보정값이 필요하다는 것을 알 수 있었다.