• 설비공학논문집
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• 제12권6호
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• pp.599-608
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• 2000

One dimensional numerical modeling was carried out for the melting behavior of dry snow and the unsaturated flow when heat was supplied from the bottom surface. Discrepancy between the previous experimental data and the present numerical results is substantially reduced by considering the density change of water permeation layer due to the infiltration of meltwater. In the parametric study for effective thermal conductivity, it was found that the effect of this parameter to the behavior of snow melting is minor. Sensitivity analysis showed that the melting time is most sensitive to changes in supplied heat flux, snow temperature, and bulk density, whereas snow bulk density and residual saturation have a significant effect on the height of water permeation layer in snow.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.509-512
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• 2008

The objectives of the on-the-spot inspection in Honam district are to find out the situation of the damages on facilities and the reason of the damages caused by heavy snow, and to suggest the preventive plan for reducing the damages from the future heavy snow. From the results of the on-the-spot inspection, plastic houses, barns and ginseng cultivation facilities are mainly damaged by heavy snow in the Honam district, and the importance of the future heavy snow preparedness measures is highly recognized in an agricultural district. In this research, 4 kinds of alternative proposals for the heavy snow are suggested.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.75-77
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• 2003

The spatial distribution of snow cover area is a crucial input to models of hydrology and climate in alpine and other seasonally snow covered areas.The objective in our study is to develop a rapidly automatic and high accuracy snow cover mapping algorithm applicable for the Tibetan Plateau which is the most sensitive about climatic change. Monitoring regional snow extent reqires higher temoral frequency-moderate spatial resolution imagery.Our algorithm is based AVHRR and MODIS data and will provide long-term fraction snow cover area map.We present here a technique is based on the multiple endmembers approach and by taking advantages of current approaches, we developed a technique for automatic selection of local reference spectral endmembers.

• 수산경영론집
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• 제49권3호
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• pp.1-14
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• 2018

This study focuses on red snow crabs for fisheries cooperation in South Korea, North Korea, and Japan. South Korea, North Korea, and Japan have had experience in promoting red snow crab fisheries cooperation. However, this cooperation is now discontinued. South Korea, North Korea, and Japan are required to play a role in mediating South Korea in order to promote red snow crabs fisheries cooperation. South Korea has the capacity to carry out economic intervention in North Korea and Japan. This is even more so in the red snow crabs. On the other, South Korea, North Korea and Japan's red snow crabs fisheries cooperation can develop into Northeast Asian fisheries cooperation including Russia and China. This can be done through the major fisheries of the East Sea, the squid and the alaska pollocks. The role of the Korean peninsula is important in Northeast Asian fisheries cooperation.

• Communications for Statistical Applications and Methods
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• 제13권2호
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• pp.369-378
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• 2006

This Study focuses on the binary forecast of occurrence of heavy snow in Honam area based on the MOS(model output statistic) method. For our study daily amount of snow cover at 17 stations during the cold season (November to March) in 2001 to 2005 and Corresponding 45 RDAPS outputs are used. Logistic regression model and neural networks are applied to predict the probability of occurrence of Heavy snow. Based on the distribution of estimated probabilities, optimal thresholds are determined via true shill score. According to the results of comparison the logistic regression model is recommended.

• 생물환경조절학회지
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• 제3권1호
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• pp.1-9
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• 1994

본 연구는 상대적으로 활하중의 영향이 민감하게 작용하는 농업시설의 합리적 구조설계를 위하여 우리나라 60개 지역의 자료를 사용하여 중요한 설계하중의 결정요인인 단위적설중량, 순간최대풍속 및 최대신적설심의 그 적용에 관하여 검토하였고, 얻어진 결과를 요약하면 다음과 같다. 1. 적설심에 다른 단위적설중량을 분석한 결과 적설심에 따른 차이는 발견할 수 없었고 대체적으로 정규분포를 이루고 있다. 평균기온에 의하여 단위중량을 구분해본 결과 -1$^{\circ}C$ 이상에서는 단위중량이 평균 0.91kg/cm/$m^2$, -1$^{\circ}C$ 이하에서는 평균 0.58kg/cm/$m^2$로 나타나 기온에 의한 차이가 명확했다. 2. 평균최대풍속과 순간최대풍속과의 관계를 도출하여 회귀식을 유도한 결과, 일반적으로 사용하고 있는 순간최대풍속 관계식과는 약간의 차이를 보였다. 해안지방과 내륙지방에 2개지역으로 구분하여 순간최대풍속 관계식을 유도하였다. 3. 재현기간별 최대적설심과 최대신적설심을 비교한 결과, 눈이 적은 지방에서는 큰 차이가 없으나, 비교적 눈이 많은 지방의 경우 재현기간 8년에서는 24.6cm, 57년에서는 45.6cm로 큰 차이를 보여, 난방 및 적절한 관리를 전제로 설계하면 신적설에 의하여 설계하중을 크게 감소시킬 수 있음을 나타냈다. 4. 기존식과 수정식의 설계풍속(진주지역) 및 최대적설심과 최대신적설심(서산지역)의 적용시, 2연동아치형시설의 부재사용량은 각각의 경우에 대하여 +0.3배, -0.3배이었고, 2연동지붕형 시설의 부재사용량은 각각 +0.3배, -0.1배이었기 때문에 시설의 특성에 맞는 설계자료의 선정이 매우 중요하다.

• 한국도로학회논문집
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• 제14권4호
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• pp.141-148
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• 2012

PURPOSES : This study demonstrates the need for the collection of road weather information in order to perform efficient snow removal works during the winter season. Snow removal operations are usually dependent upon weather information obtained from the Automatic Weather Station provided by the Korea Meteorological Administration. However, there are some difference between road weather and weather forecasts in their scope. This is because general weather forecasts are focused on macroscopic standpoints rather than microscopic perspectives. METHODS : In this study, the relationship between snow removal works and historical weather forecasts are properly analyzed to prove the importance of road weather information. We collected both weather data and snow removal works during winter season at "A" regional offices in Gangwon areas. RESULTS : Results showed that the validation of weather forecasts for snow removal works were depended on the height difference between AWS location and its neighboring roadway. CONCLUSIONS : Namely, it appears that road weather information should be collected where AWS location and its neighboring roadway have relatively big difference in their heights.

• 한국도로학회논문집
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• 제20권2호
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• pp.109-118
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• 2018

PURPOSES : This study evaluates the efficiency of snow removal operation resources using data envelopment analysis (DEA). The results of this study can help decision-making strategies, especially for resource allocation for snow removal works on national highways. METHODS : First, regional road management offices (DMUs) for efficiency evaluation were set up, and a database (for years 2012-2016) for analysis was formed. Second, DEA was carried out by selecting input and output variables based on the constructed database. Lastly, based on the results of the DEA, the efficiency of each regional road management office was evaluated. In addition, the potential for future improvement was determined. RESULTS : The results showed that there was a large variation in efficiency of snow removal operation resources by regional offices. CONCLUSIONS : The results of this study imply that the evaluation of efficiency for snow removal operation resources is important when decisions related to snow-removal strategies are made by road management offices.

• 수산해양기술연구
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• 제49권1호
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• pp.1-17
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• 2013

The investigation for species composition and catch in the Korean deep-water of the East Sea (also known as Sea of Japan) was carried out with trammel nets of 7 mesh sizes (6.1~24.2cm) offshore Donghae (2006) and Yangyang (2007) of Korea. The catches were 1,268kg and composed of 37 species between 200m and 1,200m in depth. The principal species caught were Taknka's snailfish, salmon snailfish, red snow crab, hunchback sculpin, snow crab, spinyhead sculpin, Tanaka's eelpout, Alaska cod and so on. Those were target fish for commercial value except salmon snailfish. The mesh sizes for the largest catch were 10.6cm and 15.2cm in the fishing ground of Donghae and Yangyang, respectively. The habitat of snow crab was shallower than that of red snow crab in both areas. Trammel net enabled to investigate fish in deep-water with small fishing vessel and rather cheap expenses in contrast to bottom trawl that required too much of it. With increasing inner mesh size of trammel net the mean size of some principal species such as Taknka's snailfish, spinyhead sculpin, hunchback sculpin, Pacific cod, snow crab, red snow crab and hybrid between snow crab and red snow crab tended to be large in certain range of mesh size.

• Wind and Structures
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• 제30권4호
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• pp.325-338
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• 2020

In this paper, the improvement of the anti-snow performance of a high-speed train (HST) is studied using the unsteady Reynolds-Averaged Navier-Stokes simulations (URANS) coupled with the Discrete Phase Model (DPM). The influences of the proposed flow control scheme on the velocity distribution of the airflow and snow particles, snow concentration level and accumulated mass in the bogie cavities are analyzed. The results show that the front anti-snow structures can effectively deflect downward the airflow and snow particles at the entrance of the cavities and alleviate the strong impact on the bogie bottom, thereby decrease the local accumulated snow. The rotational rear plates with the deflecting angle of 45° are found to present well deflecting effect on the particles' trajectories and force more snow to flow out of the cavities, and thus significantly reduce the accretion distribution on the bogie top. Furthermore, running speeds of HST are shown to have a great effect on the snow-resistance capability of the flow control scheme. The proposed flow control scheme achieves more snow reduction for HST at higher train's running speed in the cold regions.