• Smart Structures and Systems
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• v.29 no.5
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• pp.653-660
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• 2022

Gravel scattering that is generated during operation of high-speed railway vehicle is cause to damage of vehicle such as windows, axle protector and so on. Especially, those are frequently occurred in winter season when snow ice is generated easily. Above all, damage of vehicle windows has not only caused maintenance cost but also increased psychological anxiety of passengers. Various methods such as heating system using copper wire, heating jacket and heating air are applied to remove snow ice generated on the under-body of vehicle. However, the methods require much run-time and man power which can be low effectiveness of work. Therefore, this paper shows that large-area heating system was developed based on heating coat in order to fundamentally prevent snow ice damage on high-speed railway vehicle in the winter season. This system gives users high convenience because that can remotely control the heating system using IoT-based wireless communication. For evaluating the applicability to railroad sites, a field test on an actual high-speed railroad operation was conducted by applying these techniques to the brake cylinder of a high-speed railroad vehicle. From the results, it evaluated how input voltage and electric power per unit area of the heating specimen influences exothermic performance to draw the permit power condition for icing. In the future, if the system developed in the study is applied at the railroad site, it may be used as a technique for preventing all types of damages occurring due to snow ice in winter.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.4
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• pp.32-40
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• 2008

In this study, we monitor ice cap using calculated NDSI from September to December in 2001, 2003, 2006, 2007 and snow cover area in 2007 decrease by compare with 2001. Global warming is one of the most important issue in this world. Because global-warming is the reason of various meteorological disasters and extreme weather events in these days and snow and glaciers showed that global warming effect most easily. Snow and glaciers play an important role in Earth cooling system because of their high reflectance. The present study has been carried out monitoring ice cap in Himalayas, using MODIS(Moderate Resolution Imaging Spectroradiometer)data. Indicator to monitoring ice cap, NDSI(Normalized Differenced Snow Index) was used in this study. The NDSI is a spectral band ratio that takes advantage of the spectral differences of snow in visible and short-wave infrared domain to detect snow cover area versus non-snow cover area in a scene. This study is quantitative evaluation about effect of global warming for icecap.

• Asia-Pacific Journal of Business
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• v.14 no.2
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• pp.153-165
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• 2023

Purpose - The purpose of this study is to derive sub-group of Chinese residents to Harbin International Ice and Snow Festival through market segmentation and to identify their characteristics of each group. Design/methodology/approach - The survey was conducted with a total of 405 Chinese residents, and empirical analysis was conducted using SPSS program. Findings - As a result of the analysis, four factors were derived. Based on the factors, four sub-markets were derived by conducting cluster analysis for market segmentation. Market strategies for each sub-group were discussed based on significant differences between clusters according to demographic characteristics. Research implications or Originality - The results of this study contribute to find out potential target market of Chinese residents, and to provide data for better positing of Harbin International Ice and Snow Festival.

• Clean Technology
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• v.10 no.4
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• pp.177-187
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• 2004

Dry ice snow jet was produced by high-pressure expansion of liquid carbon dioxide and subsequent acceleration by carrier gas flow. Removal mechanism for coating was not so different from that for contaminating particles on the surface. The removal of coating was quantitatively described by Hutchings' equation. The two parameters obtained from the plot, were used to predict the removal rate or the specific coating area removed by a unit mass of carbon dioxide. Their values also enhanced the reliability of the experimental data and enabled the experimental errors corrected. Hutchings' plots obtained with various values of either stand-off distance or nozzle length tends to meet apparently at a single unique point at which the scar-size enlargement by focusing jet plume was balanced with that by spreading it.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1923-1924
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• 1996

Some part of the route in KEPCO 765kV transmission line being constructed passes through a high mountain area which is 800m above the sea level (Taebaek, Sabuk area in Gangwon province). This area is the top part of Taebaek mountains corresponding to the backbone of korean peninsula and has lots of snow during the winter season because the winter seasonal wind gone up along the mountainside of Taebaek Mts. meets open air of the East sea. KEPCO has experienced 63 faults of T/L between 1968 and 1993 in this area, which is a very serious problem. Especially 154kV Hwang-Ji T/L fault in 1990, 2 was a unprecedented case which needs to be analyzed carefully to take proper measures. After reviewing ice and snow loading conditions and analyzing the fault of Hwang-Ji T/L, we're going to determine the revisement of ice and snow loading condition in this area to increase reliability of 765kV transmission line.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.663-668
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• 1997

In Korea, the temperature of winter seasons are really severe and cause lot's of snow-falling and iceing in the pavements. Several de-iceing mehtod have generally been adopted to melt the ice on the surface of pavement. Therefore, the Study of experimental in the first stage was given to the verification of the icers's effects. First, Contrete and asphalt pavement specimens were made and scattered with a CaC2-deicers. then 3cm and 5cm thickness of artificial snow were prepared on the surface of specimens. It reveals that the early calorification due to de- icers as high as the temperature of laboratory increases within about 10 minutes and last for more then 2 hours and the test of ice-formation on the surface of contrete and asphalt specimen due to snow leads to the similar rate of freezing time about 20 minutes. Second, three kinds of de-icers, such as CaC2 CaC2+Nacl, Cacl Flaket are rested in the snowy highway to check the iceing-resistance. The CaC2 is proved to be the most effective de-icers so far.

• Bulletin of the Korean Chemical Society
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• v.32 no.6
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• pp.2105-2108
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• 2011

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.438-439
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• 1999

남극은 인위적인 오염원에서 멀리 떨어져 있고 가장 깨끗한 환경을 유지하고 있기 때문에 배경환경으로써 평가되어져 왔다. 따라서 ice core 안에서, 시간에 따른 용해성 이온종들의 조성 변화는 지구 대기조성 변화를 나타내는 것으로 알려져있다. 특히 ice cores나 눈 속에 존재하는 황산염과 MSA(Methan Sulfonic Acid)는 해양생물의 활동도 변화론 연구하는데 있어 유용한 도구를 제공해주며, 그것은 과거 기상적 변화와 관련이 있다.(중략)

• Korean Journal of Remote Sensing
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• v.23 no.6
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• pp.507-520
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• 2007

Satellite passive microwave(PM) sensors have been observing polar sea ice concentration(SIC), ice temperature, and snow depth since 1970s. Among them SIC is playing an important role in the various studies as it is considered the first factor for the monitoring of global climate and environment changes. Verification and correction of PM SIC is essential for this purpose. In this study, we calculated SIC from KOMPSAT-1 EOC images obtained from Arctic sea ice edges from July to August 2005 and compared with SSM/I SIC calculated from NASA Team(NT) algorithm. When we have no consideration of sea ice types, EOC and SSM/I NT SIC showed low correlation coefficient of 0.574. This is because there are differences in spatial resolution and observing time between two sensors, and the temporal and spatial variation of sea ice was high in summer Arctic ice edge. For the verification of SSM/I NT SIC according to sea ice types, we divided sea ice into land-fast ice, pack ice, and drift ice from EOC images, and compared them with SSM/I NT SIC corresponding to each ice type. The concentration of land-fast ice between EOC and SSM/I SIC were calculated very similarly to each other with the mean difference of 0.38%. This is because the temporal and spatial variation of land-fast ice is small, and the snow condition on the ice surface is relatively dry. In case of pack ice, there were lots of ice ridge and new ice that are known to be underestimated by NT algorithm. SSM/I NT SIC were lower than EOC SIC by 19.63% in average. In drift ice, SSM/I NT SIC showed 20.17% higher than EOC SIC in average. The sea ice with high concentration could be included inside the wide IFOV of SSM/I because the drift ice was located near the edge of pack ice. It is also suggested that SSM/I NT SIC overestimated the drift ice covered by wet snow.

• International Journal of Highway Engineering
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• v.17 no.5
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• pp.1-10
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• 2015

PURPOSES : A finite difference model considering snow melting process on porous asphalt pavement was derived on the basis of heat transfer and mass transfer theories. The derived model can be applied to predict the region where black-ice develops, as well as to predict temperature profile of pavement systems where a de-icing system is installed. In addition, the model can be used to determined the minimum energy required to melt the ice formed on the pavement. METHODS : The snow on the porous asphalt pavement, whose porosity must be considered in thermal analysis, is divided into several layers such as dry snow layer, saturated snow layer, water+pavement surface, pavement surface, and sublayer. The mass balance and heat balance equations are derived to describe conductive, convective, radiative, and latent transfer of heat and mass in each layer. The finite differential method is used to implement the derived equations, boundary conditions, and the testing method to determine the thermal properties are suggested for each layer. RESULTS: The finite differential equations that describe the icing and deicing on pavements are derived, and we have presented them in our work. The framework to develop a temperature-forecasting model is successfully created. CONCLUSIONS : We conclude by successfully creating framework for the finite difference model based on the heat and mass transfer theories. To complete implementation, laboratory tests required to be performed.