• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.1292-1294
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• 2003

This paper presents the results of research and analysis with the satellite-derived snow data. It provides the main climatic characteristics of snow cover in China and shows the variation and distribution of snow in regions of Xinjiang, Inter Mongolia and Tibet plateau. The study reveals the vicissitude periods of winter snow cover in Tibetan Plateau by using wavelet analysis with the data from 1980 to 2001. It has about 10 years large period and 3-5 years small period. The analysis shows that the extension of snow increased in recent years in Xinjiang. The results of analysis proves the relationship between winter snow cover in Tibetan Plateau and next summer precipitation in the middle and lower reaches of the Yangtze River. They have good correlation.

• Journal of Ecology and Environment
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• 제40권1호
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• pp.55-65
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• 2016

Background: In this article, it was analyzed how snow melting affects the assembly of lichen and moss communities in a small area of the coastal region of Barton Peninsula, which is in maritime Antarctic. In the small area, even though there is a huge gap of difference of the environment between the snow-filled area and snow-melt one, the latter did not have distinctive environmental gradients. Results: Depending on the snow melting time, coverage and species diversity of lichens and mosses tend to increase remarkably. For species with significant changes depending on the snow-covered period, there are Andreaea regularis, crustose lichens, Placopsis contortuplicata, Usnea aurantiaco-atra, and snow algae. In this area, the process of vegetation assembly process has shown the directional development in the order of snow algae${\rightarrow}$crustose, lichen sub-formation${\rightarrow}$fruticose lichen, moss cushion sub-formation (Andreaea sociation)${\rightarrow}$fruticose lichen, and moss cushion sub-formation (Usnea sociation), according to the order of snow melting. These directional development stages are shown in gradual change in small area with the snow melting phenomena. However, in the snow-free area, where water is sufficiently supplied, it is expected that moss carpet sub-formation (Sanionia sociation) will be developed. Vegetation development in the small area with the snow melting phenomena, depending on differences of resistance on snow kill and moisture settled by species in according to the time of snow melting, tolerance model to form community is followed. Conclusions: The research results explain the development of vegetation in the Antarctic tundra and its spatial distribution according to the period for growth of lichens and mosses in the summer time by differences of snow melting in the small area. In the future, if research for the community development process in a large scale will be done, it will be helpful to figure out temporal and spatial dynamic of vegetation in the Antarctic tundra where snow and glaciers melt rapidly due to climatic warming.

• 대한원격탐사학회지
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• 제33권4호
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• pp.401-410
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• 2017

Estimation of snow depth using optical image is conducted by using correlation with Snow Cover Fraction (SCF). Various algorithms have been proposed for the estimation of snow cover fraction based on Normalized Difference Snow Index (NDSI). In this study we tested linear, quadratic, and exponential equations for the generation of snow cover fraction maps using data from the Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua satellite in order to evaluate their applicability to the complex terrain of South Korea and to search for improvements to the estimation of snow depth on this landscape. The results were validated by comparison with in-situ snowfall data from weather stations, with Root Mean Square Error (RMSE) calculated as 3.43, 2.37, and 3.99 cm for the linear, quadratic, and exponential approaches, respectively. Although quadratic results showed the best RMSE, this was due to the limitations of the data used in the study; there are few number of in-situ data recorded on the station at the time of image acquisition and even the data is mostly recorded on low snowfall. So, we conclude that linear-based algorithms are better suited for use in South Korea. However, in the case of using the linear equation, the SCF with a negative value can be calculated, so it should be corrected. Since the coefficients of the equation are not optimized for this area, further regression analysis is needed. In addition, if more variables such as Normalized Difference Vegetation Index (NDVI), land cover, etc. are considered, it could be possible that estimation of national-scale snow depth with higher accuracy.

• 대한원격탐사학회지
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• 제34권4호
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• pp.625-638
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• 2018

In this paper, we derive i) a function to estimate snow cover fraction (SCF) from a MODIS satellite image that has a wide observational area and short re-visit period and ii) a function to determine snow depth from the estimated SCF map. The SCF equation is important for estimating the snow depth from optical images. The proposed SCF equation is defined using the Gaussian function. We found that the Gaussian function was a better model than the linear equation for explaining the relationship between the normalized difference snow index (NDSI) and the normalized difference vegetation index (NDVI), and SCF. An accuracy test was performed using 38 MODIS images, and the achieved root mean square error (RMSE) was improved by approximately 7.7 % compared to that of the linear equation. After the SCF maps were created using the SCF equation from the MODIS images, a relation function between in-situ snow depth and MODIS-derived SCF was defined. The RMSE of the MODIS-derived snow depth was approximately 3.55 cm when compared to the in-situ data. This is a somewhat large error range in the Republic of Korea, which generally has less than 10 cm of snowfall. Therefore, in this study, we corrected the calculated snow depth using the relationship between the measured and calculated values for each single image unit. The corrected snow depth was finally recorded and had an RMSE of approximately 2.98 cm, which was an improvement. In future, the accuracy of the algorithm can be improved by considering more varied variables at the same time.

• 대한원격탐사학회지
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• 제25권2호
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• pp.193-203
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• 2009

적설은 지표 에너지수지를 결정하는 중요한 변수중의 하나이다. 위성자료를 이용하여 지면 정보를 산출함에 있어서 적설과 구름을 구분하는 것은 매우 중요한 위성전처리 과정이다. 일반적으로 잘못된 적설과 구름의 분류는 위성자료를 이용한 지면 정보 산출에 있어서 직접적인 오차 요인이 된다. 따라서, 본 연구에서는 원격탐사 자료를 이용하여 적설 지역을 탐지하는 알고리즘에 대해서 연구하고자 한다. 적설역을 탐하지 하기 위해서, 가장 많이 사용되는 정규화 적설 지수(NDSI: Normalized Difference Snow Index)를 사용하지 않고 가시채널과 적외 채널을 이용한 방법을 제시하였다. COMS 기상영상기 (MI: Meteorological Imager) 채널에서는 정규적설 지수 산출 시 요구되는 근적외 채널을 탑재하지 않기 때문이다. 가시 채널을 이용한 적설 탐지는 구름이 혼재되어 있지 않은 지역에서는 잘 탐지하였으나 구름과 혼재되어 있는 지역에서는 어려움이 있다. 이러한 어려움을 보완하기 위해 적외채널 온도차 ($11{\mu}m\;-\;3.7{\mu}m$)를 이용하는 방법을 수행하였다. 온도차를 이용하는 방법은 가시채널만을 적용했을 때 보다는 향상된 탐지 능력을 보인다.

• 한국조리학회지
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• 제13권1호
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• pp.112-118
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• 2007

This study was carried out to investigate the quality characteristics of snow crab cream soup in order to seek the possibility of using fresh yams and potatoes instead of roux as thickening agents. The highest crude lipid(p<.05) and moisture(p<.001) were examined for the snow crab cream soup with yams and with potatoes as thickening agents($S_1$),($S_2$). The highest pH levels of $S_2(5.75)$ for the snow crab cream soup with yams and with potatoes were 75% and 25%. respectively. The highest lightness of 71.51(L value) was found in the 100% potato as a thickening agent($S_5$)(p<.001). The redness(a value) and yellowness(b value) were increased by adding potatoes to the snow crab soup(a=p<.001), (b=p<.01). Viscosity was increased by potato contents, and highest for the snow crab cream soup($S_5$) (p<.001). In sensory evaluation, the highest sensory scores for flavor and texture(p<.001) of mean 5.11 and 5.05, respectively, were obtained from the snow crab cream soup with yams(75%) and with potatoes(25%)($S_4$). The highest overall acceptability of mean 5.11 was found in the snow crab cream soup with yams(50%) and with potatoes(50%) as thickening agents($S_3$)(p<.001).

• 웰빙융합연구
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• 제5권1호
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• pp.9-22
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• 2022

Purpose: The purpose of this study is to develop a kimchi recipe for immunity enhancement using snow crab, which has high food value in the era of COVID-19. Research design, data and methodology: The snow crab kimchi manufacturing method of this study includes the steps of preparing a kimchi seasoning containing snow crab seasoning and chitosan powder. Kimchi seasoning is made by adding 5 parts by weight of crab seasoning and 1 part by weight of chitosan powder to 100 parts by weight of the basic kimchi seasoning prepared by mixing radish, minced garlic, minced ginger, onion juice, anchovy sauce, red pepper powder and glutinous rice paste. Results: It was possible to develop new flavors, possibilities and characteristics of snow crab kimchi by extending the health and functional effects, taste, and preservation period without significantly changing the unique manufacturing method, taste and function of kimchi, including snow crab. Conclusions: Snow crab kimchi was excellent in taste and aroma while enhancing the health functions of the body, such as improving people's immunity. The developed snow crab kimchi manufacturing method can not only improve people's health, but also expand the choice of preference for kimchi taste and shelf life.

• 한국수자원학회논문집
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• 제36권5호
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• pp.851-861
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• 2003

적설 및 융설모의를 포함하여 소양강댐과 충주댐에 대한 유출모의를 수행하였다. 사용한 모의모형은 탱크모형의 수정 형태로서 직렬 3단 탱크와 맥동 응답함수로 이루어져 있다. 매개변수의 추정에는 컴플렉스 혼합진화 (SCE-UA) 전역최적화 기법을 사용하였다. 적설 및 융설모의를 위하여 유역을 고도별로 4개 영역으로 구분하였으며 고도에 따른 기온감률은 0.6$^{\circ}C$/100m로 하였다. 모의 결과 12∼2월 사이에 이 지역에 내리는 강수는 대부분 눈으로 쌓여 있다가3∼4월에 녹아서 유출되었다. 소양강댐의 3∼4월 평균 유출량은, 융설모의를 하는 경우가 하지않는 경우에 비하여 관측 유출량의 약 1/5이 증가되었다. 충주댐의 경우는 융설 모의로 인하여 관측 평균 유출량의 약 1/4에 이르는 유출량이 증가되었다. 그렇지만 두 댐 모두, 융설을 포함하여 유출을 모의하 였음께도 불구하고, 모의 유출량이 관측 유출량보다 작았다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2008년도 학술발표회 논문집
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• pp.294-298
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• 2008

Snow cover is a potential water resource for later spring and summer seasons as well as a thermal mirror with high reflectivity causing decreases of surface air temperature during cold winter seasons. In this study, current and future changes in Northern Hemisphere snow extent and their potential linkages with atmospheric circulation are examined. The NOAA AVHRR visible snow extent (1967-2006) data as well as observational (NCEP-DOE 1979-2006) and modeled (GFDL 2.1 2081-2100) pressure and surface air temperature data are used. Analyses of observational data demonstrate that the snow extent in meteorological spring (March to April) and summer (June to August) has significantly decreased since the late 1980s. The offset of snow seasons (the timing of snow melt in spring) have also significantly advanced particularly in Europe, East Asia, and northwestern North America. Analyses of pressure fields reveal that the spatial patterns of the earlier snow melt are associated with changes in atmospheric circulation such as the Arctic Oscillation (AO). In the positive winter AO years, multiple positive pressure departure cores in the upper troposphere (200hPa) are observed over the mid-latitude regions from March to mid-April, while a negative pressure departure core (70hPa) prevails over the Arctic Ocean. The reversed anomaly patterns related to later snow melt occur in negative winter AO years. The comparison between current and future thermal spring onsets suggest that snow melt patterns will intensify with larger greenhouse gas emissions, indicating earlier hydrological spring onset.

• Wind and Structures
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• 제28권1호
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• pp.31-47
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• 2019

The accurate prediction of snow distributions under the wind action on roofs plays an important role in designing structures in civil engineering in regions with heavy snowfall. Affected by some factors such as building shapes, sizes and layouts, the snow drifting on roofs shows more three-dimensional characteristics. Thus, the research on three-dimensional snow distribution is needed. Firstly, four groups of stepped flat roofs are designed, of which the width-height ratio is 3, 4, 5 and 6. Silica sand with average radius of 0.1 mm is used to model the snow particles and then the wind tunnel test of snow drifting on stepped flat roofs is carried out. 3D scanning is used to obtain the snow distribution after the test is finished and the mean mass transport rate is calculated. Next, the wind velocity and duration is determined for numerical simulations based on similarity criteria. The adaptive-mesh method based on radial basis function (RBF) interpolation is used to simulate the dynamic change of snow phase boundary on lower roofs and then a time-marching analysis of steady snow drifting is conducted. The overall trend of numerical results are generally consistent with the wind tunnel tests and field measurements, which validate the accuracy of the numerical simulation. The combination between the wind tunnel test and CFD simulation for three-dimensional typical roofs can provide certain reference to the prediction of the distribution of snow loads on typical roofs.