• 한국토양비료학회지
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• 제48권5호
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• pp.361-371
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• 2015

To understand the impact of 2015 spring drought on crop production of DPRK (Democratic People's Republic of Korea), we analyzed satellite and weather data to produce 2015 spring outlook of rice paddy field and rice growth in relation to weather anomaly. We defined anomaly of 2015 for weather and NDVI in comparison to past 5 year-average data. Weather anomaly layers for rainfall and mean temperature were calculated based on 27 weather station data. Rainfall in late April, early May, and late May in 2015 was much lower than those in average years. NDVI values as an indicator of rice growth in early June of 2015 was much lower than in 2014 and the average years. RapidEye and Radarsat-2 images were used to monitor status of rice paddy irrigation and transplanting. Due to rainfall shortage from late April to May, rice paddy irrigation was not favorable and rice planting was not progressed in large portion of paddy fields until early June near Pyongyang. Satellite images taken in late June showed rice paddy fields which were not irrigated until early June were flooded, assuming that rice was transplanted after rainfall in June. Weather and NDVI anomaly data in regular basis and timely acquired satellite data can be useful for grasping the crop and land status of DPRK, which is in high demand.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.1224-1226
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• 2003

Dust-storm is one of the heaviest hazardous weather which frequently affects most part of northern China in spring. Satellite multi-spectral observations can provide significant information for detecting and quantitative determining the property of dust-storm . An algorithm to monitor dust-storm automatically was developed based on satellite observation. The algorithm utilizes split widows technique and spectral classification technique and also developed a new dust remote sensing product Infra -red Difference Dust Index (IDDI) proxy dust-loading dataset using GMS-5.

• 대기
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• 제21권3호
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• pp.285-300
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• 2011

To discriminate and eliminate chaff echoes in radar measurements, a new removal algorithm in two-dimensional reflectivity composite at the height of 1.5 km has been developed by using the brightness temperature($T_B$) obtained from MTSAT-1R. This algorithm utilizes the fact that chaffs are not appeared in infrared satellite data of MTSAT-1R, but detected in radar measurements due to their significant backscattering in the given radar wavelength. The algorithm is evaluated for three different situations: chaff only, chaff mixed with convective storms, and chaff covered with clouds. The algorithm shows excellent performance for the cases of chaff only and chaff mixed with convective storms. However, the performance of the algorithm significantly depends on the presence of clouds. Thus, the statistical analysis of $T_B$ is performed in order to optimize the monthly threshold.

• 전자공학회논문지D
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• 제34D권6호
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• pp.75-82
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• 1997

Today's wireless communication needs the super-high speed for picture transmission as well as voice. The optical communication with the very wide bandwidth is suitable for this demand. To fulfill the optical wireless communication, however, the atmospheric attenuation in rainy weather condition must be overcome. In the optical satellite up-link communication between geo-satellite and earth station, the factors of attenuation are turbulence, pointing error, scattering, and so on. The most serious factor for these is the scattering by rain. Under the weather conditiion of rain and cloud, in this paper, the atmospheic attenuation which affects the optical satellite up-link communication was considered, and the optimum idameter of the optical satellite transmitting antenna in the earth station versus elevation angles, data rates and rainfall rates was presented.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.249-249
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• 2002

As Asian Dust's damage and negative effects increase, the need to investigate the weather and surroundings of the source of Asian Dust has been raised. I tried to indicate the source origin and watch changing process of the plants, weather elements in those areas by the means of NOAA AVHRR NOVI and NCEP data.

• 대한원격탐사학회지
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• 제36권4호
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• pp.645-652
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• 2020

GK2A(GEO-KOMPSAT-2A)satellite has been operating excellently since its launch in Dec 2018. The secondary payload called KSEM (Korean Space Environment Monitor) was equipped into the GK2A satellite along with AMI (Advanced Meteorological Imager) sensor. KSEM is the Korea's first operational geostationary space weather sensor and has been developed collaboratively by KHU (Kyung Hee University) and KARI (Korea Aerospace Research Institute). The interface works between KSEM and GK2A were conducted by KARI. Various interface tests, which aim for evaluating effective functionality of KSEM with the spacecraft, were intensively conducted at KARI facilities. Main tests consisted of mechanical and electrical check-up activities between the KSEM and GK2A. Interface tests of KSEM, which involve pre-launch tests such as ETB and GK2A system level tests, were conducted to evaluate functional and performance of KSEM before the launch. The tests carried out during the GK2A LEOP (Launch and Early Orbit Phase) and IOT (In Orbit Test) period (Dec 2018 ~ June 2019) showed excellent in-orbit performance of KSEM data.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.645-648
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• 2005

The COMS(Communication, Ocean and Meteorological Satellite), a multi-mission geo-stationary satellite, is being developed by KARl. The first mission of the COMS is the meteorological image and data gathering for weather forecast by using a five channel meteorological imager. The second mission is the oceanographic image and data gathering for marine environment monitoring around Korean Peninsula by using an eight channel Geostationary Ocean Color Imager(GOCI). The third mission is newly developed Ka-Band communication payload certification test in space by providing communication service in Korean Peninsula and Manjurian area. There were many low Earth orbit satellites for ocean monitoring. However, there has never been any geostationary satellite for ocean monitoring. The COMS is going to be the first satellite for ocean monitoring mission on the geo-stationary orbit. The meteorological image and data obtained by the COMS will be distributed to end users in Asia-Pacific area and it will contribute to the improved weather forecast.

• East Asian Economic Review
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• 제27권4호
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• pp.273-301
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• 2023

This study investigates the impacts of long-term climate variability on household consumption in Indonesia, a country highly vulnerable to climate change. The analysis combines household survey data from nearly 5,998 families with satellite-derived weather data from NASA POWER spanning 30 years. We use the long-term variability in temperature and precipitation as a proxy for climate change. This study examines the impact of climate change which proceeds over the long term, unlike previous studies concerning one-off or short-term climate events. In addition, using satellite data enhances the accuracy of households' exposure to climate variability. The analysis finds that households in a village with higher temperature and precipitation variability significantly consume less food. This implies that households more exposed to climate change are at higher risk of malnutrition in developing countries. This study has a limitation that it cannot rule out the potential endogeneity of choosing a climate-vulnerable residential location due to economic poorness.

• Journal of Astronomy and Space Sciences
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• 제25권4호
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• pp.435-444
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• 2008

우주 방사선은 인공위성의 오동작을 유발하거나 수명을 단축하는 주된 요인 중 하나다. 반 알렌벨트라고 불리는 전하를 띤 고에너지 입자들이 지구 자기장에 포획된 공간은 이 지역에서 운용되는 인공위성뿐만 아니라, 지구 자기장을 따라 저고도까지 도달하므로 저궤도 위성들에게도 위협이 된다. 2003년 발사된 과학기술위성 1호에는 자세 제어를 위해 사용된 태양 센서가 탑재되었다. 태양 센서에는 빛을 감지하기 위한 검출기로 실리콘 태양 전지가 사용되었는데, 이 태양 전지의 합선 전류가 시간이 지남에 따라 감소하는 것이 관측되었다. 이 연구에서는 이러한 태양전지의 특성 변화가 어떠한 요인에 의해 발생하는지 지상에서의 방사능 실험을 통해 밝히고자 한다. 이를 위해 과학기술위성 1호에서 사용된 것과 동일한 태양 전지에 여러 에너지 대역의 고에너지 전자와 양성자를 조사하고 이 때 변하는 합선 전류를 측정하였다. 그리고 NOAA POES위성 데이터를 이용하여 과학기술위성 1호에 피폭되었을 방사선량을 예측하였다. 연구 결과, 과학기술위성 1호에 나타난 실리콘 태양 전지의 감쇠 현상은 700keV에서 1.5MeV의 에너지를 갖는 양성자에 의한 것으로 밝혀졌다. 이 연구 결과는 우주에서 태양 전지의 수명을 예측하기 위한 자료로 활용될 수 있다.

• 천문학논총
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• 제15권spc2호
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• pp.1-13
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• 2000

Through the coupling between the near-earth space environment and the polar ionosphere via geomagnetic field lines, the variations occurred in the magnetosphere are transferred to the polar region. According to recent studies, however, the polar ionosphere reacts not only passively to such variations, but also plays active roles in modifying the near-earth space environment. So the study of the polar ionosphere in terms of geomagnetic disturbance becomes one of the major elements in space weather research. Although it is an indirect method, ground magnetic disturbance data can be used in estimating the ionospheric current distribution. By employing a realistic ionospheric conductivity model, it is further possible to obtain the distributions of electric potential, field-aligned current, Joule heating rate and energy injection rate associated with precipitating auroral particles and their energy spectra in a global scale with a high time resolution. Considering that the ground magnetic disturbances are recorded simultaneously over the entire polar region wherever magnetic station is located, we are able to separate temporal disturbances from spatial ones. On the other hand, satellite measurements are indispensible in the space weather research, since they provide us with in situ measurements. Unfortunately it is not easy to separate temporal variations from spatial ones specifically measured by a single satellite. To demonstrate the usefulness of ground magnetic disturbance data in space weather research, various ionospheric quantities are calculated through the KRM method, one of the magneto gram inversion methods. In particular, we attempt to show how these quantities depend on the ionospheric conductivity model employed.