• Title/Summary/Keyword: snow ice

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A Study on the Characteristics of the Earth Heat Extraction Using Termosyphon (Termosyphon의 지열채열 성능에 관한 고찰)

  • Shin, H.J.;Seo, J.Y.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.5 no.3
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    • pp.226-233
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    • 1993
  • Thermosyphons are simple devices that can passively transport thermal energy over relatively large distance with little temperature degradation. Especially, the thermosyphon system requires no costly energy input and is completely maintenance free. These attributes permit the use of low grade thermal energy for thermal control of structures including the stabilization of highway foundations. This paper presents the experimental results of the snow melting system in which thermosyphon was utilized to ransfer the earth energy to the pavement to remove snow and ice. The test facility, three earth heated and one unheated test panels, is designed to investigate the variables associated with removing snow and ice from pavement surfaces. The results of these test show that the earth heated panel surface temperature is higher $2{\sim}6^{\circ}C$ than unheated panel when the ambient air temperature is $-7^{\circ}C$. The thermal performance of this earth source thermosyphon system for road heating showed that there was no snow on the heated test panels when the snowfall was 5cm average for the region.

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Development of Mathematical Model for Both Solute Transport in Snow and Isotopic Evolution of Snowmelt (눈 속에서의 용질이동 및 융설의 동위원소변동에 관한 모델개발)

  • Lee, Jeonghoon
    • Journal of Soil and Groundwater Environment
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    • v.17 no.5
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    • pp.31-39
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    • 2012
  • Chemical and isotopic variations of snowmelt provide important clues for understanding snowmelt processes and the timing and contribution of snowmelt to catchment or watershed in spring. The newly developed model includes a hydraulic exchange between mobile and immobile water (${\omega}$), and isotopic exchanges between both mobile water and ice ($f_1$) and immobile water and ice ($f_2$). Since the new model is based on the mobile-immobile water conceptualization, which is widely used for describing chemical tracer transport in snow, it allows simultaneous calculations of chemical as well as isotopic variations in snowpack discharge. We compare the model results with a study of solute transport and isotopic evolution of snowmelt in snow, using artificial rain-on-snow experiments with conservative anion ($Br^-$). These observations are used to test the newly developed model and to better understand physical processes in a seasonal snowpack where our model simulates the chemical and isotopic variations.

A Study on the Speed Sea Trial on the Ice Field for Ice Breaking Research Vessel "Araon" (쇄빙연구선 "Araon"호를 활용한 빙해역 속력 시운전에 관한 연구)

  • Kim, Hyun-Soo;Lee, Chun-Ju;Jeong, Seong-Yeob;Choi, Kyung-Sik
    • Journal of the Society of Naval Architects of Korea
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    • v.48 no.5
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    • pp.421-425
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    • 2011
  • To know the speed performance of "ARAON" in Arctic ice field, the measurement of ice properties which is ice thickness & strength, snow depth and free board were performed on July 2010. The measuring method of nautical signals such as heading angle, power of engine, wind & current information etc. was described in this paper. The speed sea trials in ice were performed on the four different positions with different ice properties and engine powers because the uniform level ice is not detected in the Chukchi Sea. The test field was partially constrained ice floe with hummocks and it was superposed with small broken ice pieces each other. All of the measured ice properties were compared and evaluated according to the results of sea trial. The relations between speed, ice thickness, strength and power were summarized. Consequently according to the sea trial results, the speed of ARAON is 2.78knots at the 2.49m ice thickness with 6.55MW engine power.

Study on Characteristics of Snowfall and Snow Crystal Habits in the ESSAY (Experiment on Snow Storms At Yeongdong) Campaign in 2014 (2014년 대설관측실험(Experiment on Snow Storms At Yeongdong: ESSAY)기간 강설 및 눈결정 특성분석)

  • Seo, Won-Seok;Eun, Seung-Hee;Kim, Byung-Gon;Ko, A-Reum;Seong, Dae-Kyeong;Lee, Gyu-Min;Jeon, Hye-Rim;Han, Sang-Ok;Park, Young-San
    • Atmosphere
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    • v.25 no.2
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    • pp.261-270
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    • 2015
  • Characteristics of snowfall and snow crystal habits have been investigated in the campaign of Experiment on Snow Storms At Yeongdong (ESSAY) using radiosonde soundings, Global Navigation Satellite System (GNSS), and a digital camera with a magnifier for taking a photograph of snowfall crystals. The analysis period is 6 to 14 February 2014, when the accumulated snowfall amount is 192.8 cm with the longest snowfall duration of 9 days. The synoptic situations are similar to those of the previous studies such as the Low pressure system passing by the far South of the Korean peninsula along with the Siberian High extending to northern Japan, which eventually results in the northeasterly or easterly flows and the long-lasting snowfall episodes in the Yeongdong region. In general, the ice clouds tended to exist below around 2~3 km with the consistent easterly flows, and the winds shifted to northerly~northwesterly above the clouds layer. The snow crystal habits observed in the ESSAY campaign were mainly dendrite, consisting of 70% of the entire habits. The rimed habits were frequently captured when two-layered clouds were observed, probably through the process of freezing of super-cooled droplets on the ice particles. The homogeneous habit such as dendrite was shown in case of shallow clouds with its thickness of below 500 m whereas various habits were captured such as dendrites, rimed dendrites, aggregates of dendrites, plates, rimed plates, etc in the thick cloud with its thickness greater than 1.5 km. The dendrites appeared to be dominant in the condition of cloud top temperature specifically ranging $-12{\sim}-16^{\circ}C$. However, the association of snow crystal habits with temperature and super-saturation in the cloud could not be examined in the current study. Better understandings of characteristics of snow crystal habits would contribute to preventing breakdown accidents such as a greenhouse destruction and collapse of a temporary building due to heavy snowfall, and traffic accidents due to snow-slippery road condition, providing a higher-level weather information of snow quality for skiers participating in the winter sports, and estimating more accurate snowfall amount, location, and duration with the fallspeed of solid precipitation.

Global Ocean Data Assimilation and Prediction System 2 in KMA: Operational System and Improvements (기상청 전지구 해양자료동화시스템 2(GODAPS2): 운영체계 및 개선사항)

  • Hyeong-Sik Park;Johan Lee;Sang-Min Lee;Seung-On Hwang;Kyung-On Boo
    • Atmosphere
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    • v.33 no.4
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    • pp.423-440
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    • 2023
  • The updated version of Global Ocean Data Assimilation and Prediction System (GODAPS) in the NIMS/KMA (National Institute of Meteorological Sciences/Korea Meteorological Administration), which has been in operation since December 2021, is being introduced. This technical note on GODAPS2 describes main progress and updates to the previous version of GODAPS, a software tool for the operating system, and its improvements. GODAPS2 is based on Forecasting Ocean Assimilation Model (FOAM) vn14.1, instead of previous version, FOAM vn13. The southern limit of the model domain has been extended from 77°S to 85°S, allowing the modelling of the circulation under ice shelves in Antarctica. The adoption of non-linear free surface and variable volume layers, the update of vertical mixing parameterization, and the adjustment of isopycnal diffusion coefficient for the ocean model decrease the model biases. For the sea-ice model, four vertical ice layers and an additional snow layer on top of the ice layers are being used instead of previous single ice and snow layers. The changes for data assimilation include the updated treatment for background error covariance, a newly added bias scheme combined with observation bias, the application of a new bias correction for sea level anomaly, an extension of the assimilation window from 1 day to 2 days, and separate assimilations for ocean and sea-ice. For comparison, we present the difference between GODAPS and GODAPS2. The verification results show that GODAPS2 yields an overall improved simulation compared to GODAPS.

Impacts of Aerosol Loading on Surface Precipitation from Deep Convective Systems over North Central Mongolia

  • Lkhamjav, Jambajamts;Lee, Hyunho;Jeon, Ye-Lim;Seo, Jaemyeong Mango;Baik, Jong-Jin
    • Asia-Pacific Journal of Atmospheric Sciences
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    • v.54 no.4
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    • pp.587-598
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    • 2018
  • The impacts of aerosol loading on surface precipitation from mid-latitude deep convective systems are examined using a bin microphysics model. For this, a precipitation case over north central Mongolia, which is a high-altitude inland region, on 21 August 2014 is simulated with aerosol number concentrations of 150, 300, 600, 1200, 2400, and $4800cm^{-3}$. The surface precipitation amount slightly decreases with increasing aerosol number concentration in the range of $150-600cm^{-3}$, while it notably increases in the range of $600-4800cm^{-3}$ (22% increase with eightfold aerosol loading). We attempt to explain why the surface precipitation amount increases with increasing aerosol number concentration in the range of $600-4800cm^{-3}$. A higher aerosol number concentration results in more drops of small sizes. More drops of small sizes grow through condensation while being transported upward and some of them freeze, thus increasing the mass content of ice crystals. The increased ice crystal mass content leads to an increase in the mass content of small-sized snow particles largely through deposition, and the increased mass content of small-sized snow particles leads to an increase in the mass content of large-sized snow particles largely through riming. In addition, more drops of small sizes increase the mass content of supercooled drops, which also leads to an increase in the mass content of large-sized snow particles through riming. The increased mass content of large-sized snow particles resulting from these pathways contributes to a larger surface precipitation amount through melting and collision-coalescence.

The Relationships Between Motivation, Prior Knowledge, Involvement, Attitude, and Behavioral Intention: Focusing on Harbin International Ice and Snow Festival (축제 방문동기, 사전지식, 관여도가 태도 및 행동의도에 미치는 영향에 관한 연구: 중국하얼빈국제빙설축제를 중심으로)

  • Kim, Sung-Bum;Kwon, Ki-Joon
    • Asia-Pacific Journal of Business
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    • v.13 no.1
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    • pp.317-333
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    • 2022
  • Purpose - The purpose of this study is to investigate the interrelationships between visitor motivations, attitude, and behavioral intention toward the Harbin International Ice and Snow Festival, China. It is also to test moderating roles of gender and past travel experience between these factors. Design/methodology/approach - Data was collected from potential Chinese visitors, after which 420 usable surveys were processed. Findings - To investigate our hypotheses, we used descriptive, confirmatory factor analysis, and structural equation modeling. We found that aesthetic attractiveness, purchase of local products, and involvement had positive effects on attitude toward the festival. Attitude toward the festival had a significant effect on behavioral intention to visit. Finally, it was also found that gender and past travel experience significantly moderated the interrelationships between these factors. Research implications or Originality - Theoretical and managerial implications, as well as, suggestions for future research are discussed.

Winter Olympics Mascots: Features and Attributes

  • Myeong Hee, SEONG;Dong Geun, LEE;Hyuk Jin, LEE
    • Journal of Sport and Applied Science
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    • v.7 no.1
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    • pp.1-10
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    • 2023
  • Purpose: This paper analyzed the features of Winter Olympics mascots in chronological order by examining the evolution of mascots and presented the attributes of the Winter Olympics mascots from Innsbruck 1976 to Beijing 2022. Research design, data, and methodology: This paper conducted an exploratory study on the thinking to understand the characteristics of 13 Winter Olympics Mascots through literature review. Results: First, the mascot is a fictional character, usually an artificial character that represents the locality of the host city, including animals, human figures, and local inhabitants. Second, Schneemann, Innsbruck 1976 was known as the first official Winter Olympics mascot. Third, 19 mascots out of a total of 24 mascots were created using animals. Conclusions: The six attributes of the Winter Olympics mascots were identified: friendliness, symbolic meaning, originality, diversity, value, and identity of a special location. Above all, Winter Olympics has a locality that includes areas covered with ice and snow. From this point of view, the Olympics mascot highlights the image of snow and ice and the physical environment that includes it.

Research on Countermeasures for Ballast-Flying Phenomenon by Accreted Snow/Ice from High-speed trains (고속철도 설빙낙하에 의한 자갈비산 방지대책 연구)

  • Kwon Hyeok-Bin;Nam Seong-Won;Kim Dae-Sang;Lee Il-Wha;Han Jin-Seok
    • Proceedings of the KSR Conference
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    • 2004.06a
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    • pp.229-234
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    • 2004
  • When trains run over a snow-covered track at high speed, the snow accereted under car bodies may drop during train running. The dropped snow lumps scatter the ballast on the track damaging the car body and the environment along the track in snowy regions. In this study, various countermeasures to prevent the ballast from scattering has been investigated and compared. Furthermore, the implementation of the ballast-flying prevention methods to passing-by station has been examined through which the KTX train passes about 300km/h speed.

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