• 한국농림기상학회:학술대회논문집
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• 한국농림기상학회 2001년도 춘계 학술발표논문집
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• pp.131-134
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• 2001

잣나무는 목재생산뿐만 아니라 종자생산이라는 이중적 가치와 효용성을 지닌 주요 경제수종의 하나이다. 하지만 그 동안 대면적에 조성된 잣나무 임분은 인건비의 상승과 저가의 외국산 잣의 수입으로 인해 잣 생산을 통한 수익을 기대하기가 어려운 실정이 되었다. 따라서 잣나무림의 수익 증대를 위해서는 고품질의 종자와 양질의 목재를 증산시킬 수 있는 부가가치가 높은 임분으로의 유도가 필요하다.(중략)

• 한국농림기상학회:학술대회논문집
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• 한국농림기상학회 2001년도 춘계 학술발표논문집
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• pp.61-64
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• 2001

대관령 인근 고랭지는 표고가 높아 여름철에도 서늘하여 오래 전부터 씨감자와 호냉성원예작물의 주산지로 발전되어 왔다. 이러한 저온기후자원을 이용하여 농업활동이 이루어지는 고랭지는 산지의 특이한 지형조건 때문에 날씨변화가 심하고 이에 따른 작물피해가 잦다. 기상청 자동기상관 측장치(automated weather station : AWS)가 일부 지점에 설치되어 있으나 기온과 바람 강우량만이 관측되고 있어 농업적인 이용에는 한계가 있다.(중략)

• 한국농림기상학회:학술대회논문집
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• 한국농림기상학회 2012년도 학술발표논문집
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• pp.84-87
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• 2012

• 한국농림기상학회:학술대회논문집
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• 한국농림기상학회 2012년도 학술발표논문집
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• pp.139-144
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• 2012

• 한국항공운항학회지
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• 제25권4호
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• pp.124-129
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• 2017

Clouds are an important factor in aircraft flight. In particular, a significant impact on small aircraft flying at low altitude. Therefore, we have verified and characterized the low level cloud prediction data of the Unified Model(UM) - based Local Data Assimilation and Prediction System(LDAPS) operated by KMA in order to develop cloud forecasting service and contents important for safety of low-altitude aircraft flight. As a result of the low level cloud test for seven airports in Korea, a high correlation coefficient of 0.4 ~ 0.7 was obtained for 0-36 leading time. Also, we found that the prediction performance does not decrease as the lead time increases. Based on the results of this study, it is expected that model-based forecasting data for low-altitude aviation meteorology services can be produced.

• 한국환경과학회지
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• 제19권12호
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• pp.1361-1374
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• 2010

The impact of urbanization on local meteorology (e.g., surface temperature, PBL height, wind speed, etc.) in the Greater Seoul Area (GSA) was quantitatively evaluated based on a numerical modeling approach during a 1-month period of 2001 (9 Sep. through 8 Oct. 2001). The analysis was carried out by two sets of simulation scenarios: (1) with the global land use and topographic data from the U.S. Geological Survey (USGS) in 1990s (i.e., LU-USGS case) and (2) with the land use data from the Environmental Geographic Information System (EGIS) along with the 3 sec elevation data from the Shuttle Radar Topography Mission (SRTM) in 2000s (i.e., LU-EGIS case). The extension of urban areas in the GSA (especially, the southern parts of Seoul) accounted for 1.8% in the LU-USGS case and 6.2% in the LU-EGIS case. For the simulations, the surface temperature and PBL height due to urbanization in the LU-EGIS case was higher (the differences of up to $0.1^{\circ}C$ and 36 m, respectively) than those in the LU-USGS case, whereas the wind speed (up to 0.3 $ms^{-1}$) in the former was lower than that in the latter at 1500 LST. The increase in surface temperature due to urbanization in the GSA (especially, the southern parts of Seoul) was led to the strong convergence of air masses, causing the early sea breeze and its rapid propagation to inland locations. In addition, the vertical mixing motion in the extended urban areas for the LU-EGIS case was predicted to be stronger than that for the LU-USGS case and vice versa for the original urban areas.

• 대기
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• 제27권4호
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• pp.399-409
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• 2017

The impact of land cover changed by tidal flats on local meteorology in Gyeonggi Bay was quantitatively evaluated based on a numerical modeling approach during 18 days (21 June to 9 July 2013). The analysis was carried out using three sets of simulation scenarios and the land cover of tidal flats for each simulation was applied as follows: (1) the herbaceous wetland representing coastal wetlands (i.e., EXP-BASE case), (2) the barren or sparsely vegetated representing low tide (i.e., EXP-LOW case), (3) the water bodies representing high tide (i.e., EXP-HIGH case). The area of tidal flats was calculated as about $552km^2$ (the ratio of 4.7% for analysis domain). During the daytime, the change (e.g. wetlands to water) of land cover flooded by high tide indicated the decrease of temperature (average $3.3^{\circ}C$) and the increase of humidity (average 13%) and wind speed (maximum $2.9m\;s^{-1}$). The changes (e.g. wetlands to barren or sparsely vegetated) of land cover induced by low tide were smaller than those by high tide. On the other hands, the effects of changed land cover at night were not apparent both high tide and low tide. Also, during the high tide, the meteorological change in tidal flats affected the metropolitan area (about 40 km from the tidal flat).

• 대기
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• 제31권4호
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• pp.405-420
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• 2021

Forest fire happens every year at Yeongdong, Gangwon-do, due to the strong local wind during the spring time and it causes a huge damage. This wind is named "Yangganjipung" or "Yanggangjipung" that blows along Yeongdong. However, the occurrence conditions of the wind have been still unclear. To identify the occurrence mechanism of local strong wind through three-dimensional observation data, Gangwon Regional Meteorological Administration performed Joint Gangwon-Yeongdong 3D Observation Project in 2020. The special observation was carried out for 6 times from March to April. The observation data was analyzed by focusing on the structure of synoptic pressure distribution and inversion layer. The result showed that the strength of wind is different depending on the latitude of low pressure, intensity of inversion layer, and changes on height in the south-high and north-low pressure distribution. As the interval of the upper and lower parts of the inversion layer was narrow, the strength of the wind became stronger, which is one of the observational characteristics of the springtime wind pattern at Yeongdong, Gangwon-do. In future, the clear mechanism of the local wind in the Yeongdong during the spring time is expected to be verified based on the accumulative observation data and close analysis.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권1호
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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.

• 한국농림기상학회지
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• 제14권4호
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• pp.265-268
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• 2012

실외활동의 증가와 기후변화에 의한 알레르기 유발 꽃가루의 증가로 알레르기 질환 환자가 급증하고 있다. 현재 기상청에서는 홈페이지를 통하여 일별 꽃가루 농도 위험지수를 예보하고 있다. 예보모델은 농도 추정모델과 알레르기 위험도로 구성되어 있으며, 예보모델의 위험도 예측 정확도를 검증하였다. 꽃가루 농도모델은 2001~2006년 자료를 이용하여 개발하였고, 정확도는 2010~2011년 자료로 검증하였다. 수목류 정확도는 지역별로 다르게 나타났으나 5월보다 4월에 높게 나타났다. 잡초류는 9월보다 10월에 더 높게 나타났다. 본 연구 결과를 통해 기상자료를 이용한 일별 꽃가루 수와 위험도를 추정할 수 있으며, 이를 이용하여 생명기상 또는 보건기상 분야의 심층 연구가 수행될 수 있을 것이다.