• Title/Summary/Keyword: Snow

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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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    • v.5 no.3
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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.

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

  • Lee, K.S;Ko, Y.W.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.11 no.1
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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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Analysis of Road Snow-removal Infrastructure using Road Snow-removal Historical Data (도로제설 이력자료 기반 제설 인프라 분석)

  • Kim, Jin Guk;Kim, Seoung Bum;Yang, Choong Heon
    • International Journal of Highway Engineering
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    • v.19 no.3
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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
    • Proceedings of the KSRS Conference
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    • 2003.11a
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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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Estimation of Snow Damage and Proposal of Snow Damage Threshold based on Historical Disaster Data (재난통계를 활용한 대설피해 예측 및 대설 피해 적설심 기준 결정 방안)

  • Oh, YeoungRok;Chung, Gunhui
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.37 no.2
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    • pp.325-331
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    • 2017
  • Due to the climate change, natural disaster has been occurred more frequently and the number of snow disasters has been also increased. Therefore, many researches have been conducted to predict the amount of snow damages and to reduce snow damages. In this study, snow damages over last 21 years on the Natural Disaster Report were analyzed. As a result, Chungcheong-do, Jeolla-do, and Gangwon-do have the highest number of snow disasters. The multiple linear regression models were developed using the snow damage data of these three provinces. Daily fresh snow depth, daily maximum, minimum, and average temperatures, and relative humidity were considered as possible inputs for climate factors. Inputs for socio-economic factors were regional area, greenhouse area, farming population, and farming population over 60. Different regression models were developed based on the daily maximum snow depth. As results, the model efficiency considering all damage (including low snow depth) data was very low, however, the model only using the high snow depth (more than 25 cm) has more than 70% of fitness. It is because that, when the snow depth is high, the snow damage is mostly caused by the snow load itself. It is suggested that the 25 cm of snow depth could be used as the snow damage threshold based on this analysis.

Designing a Snow-removing Tool Through Ergonomic Approach

  • Jung, Kwang Tae;Nam, Jung Min
    • Journal of the Ergonomics Society of Korea
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    • v.35 no.5
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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.

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

  • Lee, Jang-Yong
    • Journal of Korean Institute of Industrial Engineers
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    • v.37 no.4
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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.

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

  • Park, Chan-Il;Kim, Dae-Sik
    • Proceedings of the KSME Conference
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    • 2000.11a
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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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Extraction of Snow Cover Area and Depth Using NOAA/AVHRR Images (NOAA/AVHRR 영상을 이용한 적설분포 및 적설심 추출)

  • Kang, Su-Man;Kwon, Hyung-Joong;Kim, Seong-Joon
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2005.10a
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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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A Study of Heavy Snow event caused Runway closed (활주로 폐쇄를 야기한 대설 사례 연구)

  • Kim, Young-Chul
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.21 no.4
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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.