• 대기
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• 제29권3호
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• pp.311-324
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• 2019

We employed a Multi-Angle Snowflake Camera (MASC) to quantitatively analyze snow particles at the ground level in the Yeongdong region of Korea. The MASC captures high-resolution photographs of hydrometeors from three angles and simultaneously measures fallspeed. Based on snowflake images of the several episodes in 2017 and 2018, we derived statistics of size, aspect ratio, orientation, complexity, and fallspeed of snow crystals, which generally showed similar characteristics to the previous studies in other regions of the world. Dominant snow crystal habits of January 22, 2018 generated by northerly were melted aggregates when 850 hPa temperature was about $-6{\sim}-8^{\circ}C$. Average fallspeed of snow crystals was $1.0m\;s^{-1}$ though its size gradually increased as temperature decreased. Another snowfall event (March 8, 2018) was driven by the baroclinic instability as accompanied with a deep trough. Snow crystal habits were largely rimed aggregates (complexity ~1.8) and melting particles of dark images. Meanwhile, in the extreme snowfall event whose snow rate was greater than $10cm\;hr^{-1}$ on January 20, 2017, main snow crystals appeared to be heavily rimed particles with relatively smaller size when convective clouds developed vertically up to 9 km in association with tropopause folding. MASC also could successfully measure a decrease in snow crystal size and an increase in riming degree after AgI seeding at Daegwallyeong on March 14, 2017.

• 한국신뢰성학회지:신뢰성응용연구
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• 제12권2호
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• pp.91-103
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• 2012

Tubular markers for road safety facilities are used to lead the driver's sight line and separate the lanes on the road. Such tubular markers are usually installed on the road and frequently hit by vehicles, they are accordingly requested to assure the product durability. The traditional evaluation method of tubular markers include only quality tests of the material properties. However, most of consuming agencies in charge of road management at fields have proposed problems on long-term performance of the products hit by vehicles under various weather conditions. Therefore, the objectives of this study are to develop the reliability test methods and equipments to simulate the product failures of tubular markers due to vehicle collision and wheel compression and the delamination and discoloration of reflection sheets attached on the surface of the products under high and low temperatures.

• 환경위생공학
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• 제20권4호통권58호
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• pp.1-8
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• 2005

Pocheon is a basin geographically, and the diffusion of air pollutants is very difficult. Thus, it is essential to consider the characteristics of geographical and weather conditions before industrial complex and various air pollution sources are developed in the area. It is recommended that Environmental Impact Statements (EIS) must be carried out before any action is taken. Constantly occurring fog in the Pocheon area absorbs large amounts of acidic gases, and it transformed into the secondary pollutants such as the salts of sulfate and nitrate. Fog, which occurs very often in Pocheon area, was analyzed for its acid components. Conversion from the gaseous sulfur dioxide into sulfate ion is relatively high, $86\~90\%$ while $68\~76\%$ of NOx is converted into nitrate ion form.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.590-593
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• 2009

Tidal current power system is one of ocean renewable energies that can minimize the environmental impact with many advantages compared to other energy sources. Not like others, the produced energy can be precisely predicted without weather conditions and also the operation rate is very high. To convert the current into power, the first device encountered to the incoming flow is the rotor that can transform into rotational energy. The performance of rotor can be determined by various design parameters including numbers of blade, sectional shape, diameter, and etc. The stream lines near the rotating rotor is very complex and the interference effects around the system is also difficult to predict. This paper introduces the experiment of rotor performance and also the effect of design parameter on the performance of HAT rotor by CFD.

• 천문학회보
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• 제46권1호
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• pp.58.4-59
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• 2021

This presentation introduces Korea's SNIPE (Small scale magNespheric and Ionospheric Plasma Experiment) mission, formation flying CubeSat constellation. Observing particles and waves on a single satellite suffers from inherent space-time ambiguity. To observe spatial and temporal variations of the micro-scale plasma structures on the topside ionosphere, four 6U CubeSats (~ 10 kg) will be launched into a polar orbit of the altitude of ~500 km in 2021. The distances of each satellite will be controlled from 10 km to more than 100 km by formation flying algorithm. The SNIPE mission is equipped with identical scientific instruments, solid-state telescope, magnetometer, and Langmuir probe. All the payloads have a high temporal resolution (sampling rates of about 10 Hz). Iridium modules provide an opportunity to upload changes in operational modes when geomagnetic storms occur. SNIPE's observations of the dimensions, occurrence rates, amplitudes, and spatiotemporal evolution of polar cap patches, field-aligned currents (FAC), radiation belt microbursts, and equatorial and mid-latitude plasma blobs and bubbles will determine their significance to the solar wind-magnetosphere-ionosphere interaction and quantify their impact on space weather.

• 복식
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• 제65권1호
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• pp.15-29
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• 2015

The fashion items of the "Rainy Look" has become fashion items that could be worn in any weather. Accordingly, there is a need for this study to research the fashion items of the Rainy Look as its influence is becoming big enough to impact modern fashion and expand into the high fashion and street fashion. First of all, the purpose of this study is to analyze the fashion items of the Rainy Look that were represented in the high fashion and street fashion of 21st century. And the analysis was performed using the following categories: the functional aspect, aesthetic aspect, and the formativeness of fashion items. Through this, the study provided fashion styling materials using the Rainy Look fashion items. This study examined the concepts and characteristics of the Rainy Look as a literature study and analyzed its characteristics, which appeared in collections and street fashions. Especially as attires coordinated with business casuals in the street fashion, they appeared often among commuting office workers. And the conveniences of having a string in the waistline or securing storage space or detachable function. On the contrary, traditional raincoat designs appeared often in high fashion and as feminine styles, which is characterized by a slimmed waist with a use of a belt. and a flared lower part, such as shoulder patch or strap.

• 한국농공학회논문집
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• 제54권2호
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• pp.15-26
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• 2012

For stable and sustainable crop production, understanding the effects of climate changes on agricultural water resources is necessary to minimize the negative effects which might occur due to shifting weather conditions. Although various studies have been carried out in Korea concerning changes in evapotranspiration and irrigation water requirement, the findings are still difficult to utilize fordesigning the demand and unit duty of water, which are the design criteria of irrigation systems. In this study, the impact analysis of climate changes on the paddy water demand and unit duty of water was analyzed based on the high resolution climate change scenarios (specifically under the A1B scenario) provided by the Korea Meteorological Administration. The result of the study indicated that average changes in the paddy water demand in eight irrigation districts were estimated as -2.4 % (2025s), -0.2 % (2055s), and 3.2 % (2085s). The unit duty of water was estimated to increase on an average within 2 % during paddy transplanting season and within 5 % during growing season after transplanting. This result could be utilized for irrigation system design, agricultural water resource development, and rice paddy cultivation policy-making in South Korea.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.33-36
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• 2007

We have persistently constructed gridded products of surface wind/wind stress over the world ocean using satellite scatterometer (ERS and Qscat). They are available for users as the Japanese Ocean Flux data sets with Use of Remote sensing Observation (J-OFURO) data together with heat flux components. Recently, a new version data of the Qscat/SeaWinds based on improved algorithm for rain flag and high wind-speed range have been delivered, and allowed us to reconstruct gridded product with higher spatial resolution. These products are validated by comparisons with in-situ measurement data by mooring buoys such as TAO/TRITON, NDBC and the Kuroshio Extension Observation (KEO) buoys, together with numerical weather prediction model products such as the NCEP-1 and 2. Results reveal that the new product has almost the same magnitude in mean difference as the previous version of Qscat product and much smaller than the NCEP-1 and 2. On the other hand, it is slightly larger root-mean-square (RMS) difference than the previous one and NCEPs for the comparison using the KEO buoy data. This may be due to the deficit of high wind speed data in the buoy measurement. The high resolution product, together with sea surface temperature (SST) one, is used to examine a new type of relationship between the lower atmosphere and upper ocean in the Kuroshio Extension region.

• 한국지구과학회지
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• 제36권4호
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• pp.315-329
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• 2015

본 연구에서는 2005~2010년 기간 동안 영동지역의 지형성 강풍과 관련된 태백산맥 풍하측에서 관측된 기상요소들을 분석하였다. 강풍 사례는 강원지역에서 풍속이 $14ms^{-1}$ 이상인 조건을 이용하여 선정하였다. 강풍 사례는 총 15일로 나타났고, 모두 영동지역에 위치한 속초, 강릉, 동해, 그리고 태백 지역에서 발생하였다. 사례 중 태풍(세 사례) 그리고 영동지역의 대설(두 사례)과 호우(두 사례)와 관련된 7개 사례는 이 연구에서 제외하였다. 8개 강풍 사례를 분석하기 위하여 종관 일기도, 속초 고층 관측, 강릉 수직측풍, 그리고 수치모델 자료를 사용하였다. 선정된 사례는 무강수 혹은 일강수량 1mm 이하의 강수를 보였다. 종관 일기도에서 나타난 지상과 상층의 특징은 기압분포가 한반도를 중심으로 남고북저형을 보였고, 영동지역으로 온도능(warm ridge)이 위치하였다. 역전층(혹은 안정층)과 온도능은 하층 강풍대와 함께 산 정상의 약 1~3 km (925~700 hPa) 고도에 위치하였다. 또한 지역예보시스템에서 분석된 온난핵과 온도능은 산 정상 상공의 850 hPa 등압면 고도에 위치하였고, 이 고도에서 수평 온도 경도는 $0.10{\sim}0.23^{\circ}C\;km^{-1}$로 분석되었다. 이러한 분석 결과는 영동지역 강풍 예보 가이던스로 요약되었다.

• 한국농림기상학회지
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• 제21권3호
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• pp.146-157
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• 2019

우리나라 농산촌 환경의 가장 큰 특징 중 하나는 지형이 복잡하여 좁은 지역 내에서도 기상/기후 분포변이가 크다는 점이다. 이를 효과적으로 모의하기 위하여 '소기후 모형'이 개발되었고 현재까지 지속적으로 개선 연구가 진행되고 있다. 소기후 모형은 우리나라 전역에 대해 농장필지 단위까지 공간적으로 정밀한 농업기상/기후 정보를 표현할 수 있는 모형으로 기후요소별로 독자적으로 개발되었다. 소기후모형을 이용하여 2000년대에는 국지규모의 현재평년 및 미래 시나리오 기반 기후정보를 산출하였다. 평년 전자기후도는 과거 30년 기간의 월별 최저기온, 최고기온, 강수량, 일사량을 30 m 격자해상도로 상세화 한 분포도이며, 이 전자기후도를 기반으로 미래 기후변화 시나리오를 고해상도로 상세화하여 제작하였다. 이 들 전자기후도는 농업분야 기후변화 영향평가에 다양한 형태로 재가공 되어 이용되었다. 2010년대에는 농장맞춤형 기상 실황 및 예보자료를 국지규모로 생성하고 있다. 소기후 모형은 지속적인 개선 과정을 통해 일별 관측기상자료를 기반으로 실황정보를 상세화하는 기술로 발전하고 있으며, 기상청 동네예보 및 중기예보를 30 m 격자해상도로 상세 모의하여 농업분야 종사자에게 예측 정보를 실시간 제공할 수 있는 '농업기상 재해 조기경보 서비스' 기반의 핵심기술로 인정 받고 있다. 현재 상세 기상 실황 및 예보정보로는 일 최저 및 최고기온과 강수량, 일사량, 일조시간 등이 산출되고 있으며, 과거-현재-미래의 농장규모 기상정보를 토대로 각종 농작물의 생육정보와 기상재해 예측정보를 생산하고 있다.