• 제목/요약/키워드: Snow

검색결과 1,155건 처리시간 0.031초

A Preliminary Study on a Method for the Morphological and Quantitative Analyses of Individual Snow Crystals and Its Application for Field Measurement

  • Ma, Chang-Jin
    • Asian Journal of Atmospheric Environment
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    • 제5권3호
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    • pp.196-203
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    • 2011
  • The main aim of this study is to establish methods of morphological preservation and elemental quantification for individual snow crystals. Individual snow crystals were collected at a height of 20 m above ground level. To stabilize and preserve the original morphologies of the snow crystals, cyanoacrylate, which has been used to fix liquid droplets, was applied (Kasahara et al., 2000). Several different kinds of snow crystals (dendrite, sectored plate, quasi-sectored plate, and hexagonal plate) were successively stabilized using this method. The stabilized snow crystals were pretreated with acetone, and then the elemental components contained in a whole snow crystal were quantified with the Particle Induced X-ray Emission (PIXE) analytical technique. The snow crystal residual composition determined in the present study was dominated by sulfur and mineral components, and the elemental mass showed an apparent crystal size dependence, where the elemental mass gradually decreased as the crystal size increased.

제상 현상 연구를 위한 눈 융해 과정 해석 (An analysis of snow melting process for a study of defrosting phenomena)

  • 이관수;고영우
    • 설비공학논문집
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    • 제11권1호
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    • pp.38-47
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    • 1999
  • An improved one-dimensional modeling of snow melting was obtained by considering both the effect of heat capacity and the decreasing influence of porosity. Using the improved model, the effects of initial snow temperature, initial snow density and the heat flux on the snow melting were investigated. It is found that the drainage starting time is delayed and the drainage rate becomes smaller with lower initial snow temperature. ResuIts also show that the drainage starts at the same time when an initial snow density is over a certain value. Melting efficiency increases linearly with an increasing initial snow temperature. With increasing the initial density of the snow and the amount of heat supplied, the melting efficiency increases, then converges to a constant value.

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도로제설 이력자료 기반 제설 인프라 분석 (Analysis of Road Snow-removal Infrastructure using Road Snow-removal Historical Data)

  • 김진국;김승범;양충헌
    • 한국도로학회논문집
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    • 제19권3호
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    • pp.83-90
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    • 2017
  • PURPOSES : In this study, systematic road snow-removal capabilities were estimated based on previous historical data for road-snowremoval works. The final results can be used to aid decision-making strategies for cost-effective snow-removal works by regional offices. METHODS : First, road snow-removal historical data from the road snow-removal management system (RSMS), operated by the Ministry of Land, Infrastructure and Transport, were employed to determine specific characteristics of the snow-removal capabilities by region. The actual owned amount and actual used amount of infrastructure were analyzed for the past three years. Second, the regional offices were classified using K-means clustering into groups "close" to one another. Actual used snow-removal infrastructure was determined from the number of snow-removal working days. Finally, the correlation between the de-icing materials used and infrastructure was analyzed. Significant differences were found among the amounts of used infrastructure depending on snowfall intensity for each regional office during the past three years. RESULTS:The results showed that the amount of snow-removal infrastructure used for low heavy-snowfall intensity did not appear to depend on the amount of heavy snowfall, and therefore, high variation is observed in each area. CONCLUSIONS:This implies that the final analysis results will be useful when making decisions on snow-removal works.

Climatic Characteristics of the Northern Hemisphere Snow Cover observed by Satellite and its influence on the Monsoon

  • Yang, Xiangdong
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1289-1291
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    • 2003
  • Climatic characteristic and changes of snow cover over the Northern Hemisphere, Eurasian, North America and the Tibet Plateau are studied based on data of the Northern Hemisphere snow cover area observed by Satellite remote sensing from 1966 to 2003. Meanwhile, the seasons' distribution charts of the Asian snow cover are made, they provide the climatic background of snow cover. In addition, the influences of snow cover on the climate, especially on the monsoon are analysed briefly, and some significance results are concluded.

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재난통계를 활용한 대설피해 예측 및 대설 피해 적설심 기준 결정 방안 (Estimation of Snow Damage and Proposal of Snow Damage Threshold based on Historical Disaster Data)

  • 오영록;정건희
    • 대한토목학회논문집
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    • 제37권2호
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    • pp.325-331
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    • 2017
  • 최근 세계적인 기상이변으로 인해 자연재해가 빈번하게 발생하고 있으며, 겨울철 대표적인 자연재해인 대설에 의한 재난 발생 빈도도 증가하고 있다. 그러므로 대설 피해 저감이나 대설 피해액 예측에 대한 연구들이 다수 수행되고 있다. 본 연구에서는 과거 22년간 발생했던 대설 피해 사례를 재해연보에서 조사하여 시군구별로 빈도 분석을 하였다. 그 결과 대설 피해 발생 빈도가 높았던 충청도, 전라도, 강원도를 대상으로 대설피해액 예측을 위한 다중회귀모형을 구축하였다. 설명변수로 기상학적 요소인 최심신적설량, 최고기온, 최저기온, 상대습도와 사회 경제적인 요소인 시군구의 면적과 비닐하우스 면적, 농가인구, 60세 이상 농가인구를 선택하여 모형을 구축하였다. 또한 대설 피해를 야기하는 적설심에 대한 분석을 위해 최심신적설심 별 구간을 구분하여 모형을 별도로 구축하였다. 그 결과, 적설심이 낮았던 피해 사례까지를 모두 고려한 경우에는 모형의 예측력이 매우 낮았지만, 피해를 야기한 적설심이 큰 경우만을 분리하여 모형을 구축한 경우에는 70% 이상의 매우 향상된 예측력을 보였다. 이는 적설심이 25 cm 이상 큰 경우에는 적설하중에 의해 설해가 발생할 가능성이 있으며, 이를 대설 피해 기준 적설심이라고 가정할 수 있을 것으로 판단되었다.

Designing a Snow-removing Tool Through Ergonomic Approach

  • Jung, Kwang Tae;Nam, Jung Min
    • 대한인간공학회지
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    • 제35권5호
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    • pp.439-447
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    • 2016
  • Objective: The purpose of this study is to design a snow-removing tool using an ergonomic approach. Background: It is necessary to remove snow on the garden of a house or side street to prevent a fall hazard. When a user removes snow using a snow-removing tool, he or she experiences lots of physical discomfort. Therefore it is necessary to design a snow-removing tool to reduce a user's physical discomfort. Method: In this study, a new design for a snow-removing tool was developed considering user needs. The design prototype was compared with an existing tool through electromyography and subjective evaluation. Results: From the comparison evaluation, significant differences between the new design and the existing tool were identified in both muscle fatigue and subjective rating of discomfort. Conclusion: The result showed that the new design is better from the aspect of easing physical discomfort. Application: A new snow-removing tool can be developed using the design so that it can reduce a user's physical discomfort.

다 목적 제설장비 시스템 설계 (Configuration Design of Multi Purpose Snow Removal System)

  • 이장용
    • 대한산업공학회지
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    • 제37권4호
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    • pp.415-420
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    • 2011
  • Snow removal system is named for machinery which manages roads for passing of pedestrians and automobiles when snow is piled up on the road. This paper studies configuration design of snow removal system that has several functions-melting snow in the street without moving it to other place, transferring snow to the melter and cleaning road by spraying water for cleaning road. These sorts of functions are analyzed by function decomposition method of Kirshman and Fadel and, based upon which, machine parts are selected. Layout design would follow functional design to testify if the selected component satisfies space which is allowed by constraints.

특장차용 제설기의 설계 (The Design of a Snow Plow for the Special Equipment Vehicle)

  • 박찬일;김대식
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 추계학술대회논문집A
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    • pp.801-806
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    • 2000
  • This study deals with the design of snow plow for the special equipment vehicle. The purpose of the study is to develop the snow plow that can install in the special equipment vehicle such as clean up vehicle or dump truck in winter season. To do so, it is designed by 3 sub-assembly - snow shovel, main frame, and hydraulic cylinder and its support. The snow shovel consists of 3 pieces to meet the road profile and to exchange easily the damaged parts. Main frame connects the snow shovel with the hydraulic cylinder and its support and supports the weight of snow. Finally, the hydraulic cylinder and its support move the snow shovel up and down and tilt it. We designed it using 3D commercial CAD software for concurrent engineering design.

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NOAA/AVHRR 영상을 이용한 적설분포 및 적설심 추출 (Extraction of Snow Cover Area and Depth Using NOAA/AVHRR Images)

  • 강수만;권형중;김성준
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2005년도 학술발표논문집
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    • pp.254-259
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    • 2005
  • The shape of a streamflow hydrograph is very much controlled by the area and depth of snow cover in mountain area. The purpose of this study is to suggest extraction methods for snow cover area and depth using NOAA/AVHRR images in Soyanggang watershed. Snow cover area maps ware derived form channel 1, 3, 4 images of NOAA/AVHRR based on threshold value. In order to extract snow cover depth, snow cover area maps were overlaid daily snow depth data form 7 meteorological observation stations. Snow cover area and depth was mapped for period of Dec. 2002 and Mar. 2003. For evaluating snowmelt changes, depletion curve was created using daily snow cover area in the same period. It is necessary to compare these results with observed data and check the applicability of the suggested method in snowmelt simulation.

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활주로 폐쇄를 야기한 대설 사례 연구 (A Study of Heavy Snow event caused Runway closed)

  • 김영철
    • 한국항공운항학회지
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    • 제21권4호
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    • pp.106-111
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    • 2013
  • The heavy snow event occurred on JAN 4, 2010 brought huge disaster such as Gimpo International Airport runway closed, heavy delays of other airport, and property damage of 16 billion won. Though this heavy snow event is involved in the general synoptic scale heavy snow forecast, it recorded too much snow amount and longer duration than expected. To explain this unusual event, we used the conveyor belt theory. By combining the synoptic scale heavy snow forecast and the conveyor belt theory, the characteristics of heavy snow event was well explained.