• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.15 no.2
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• pp.196-203
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• 1986

The melting phenomena of horizontal cylindrical ice-bar immersed in water and air concentrically in the cylinder are experimentally investigated for the temperature range from $3.5^{\circ}C\;to\;2.5^{\circ}C$. The shapes of the melting ice-bar are recorded photographically by the shadowgraph method. The shadowgraphs of the melting ice-bar show that water adjacent to the bar flows upward for the temperature range from $3.5^{\circ}C\;to\;5.8^{\circ}C$ while above $5.8^|\circ}C$ the flow is downward direction. The local and average Nusselt numbers are obtoined with the recorded shadowgraphs and comparator. Melting shapes of the ice-bar in the air show the vortex motion in the bottom portion of the bar, whereas no vortex motion appears in the bottom portion when the bar is melted in the water.

• Korean Journal of Remote Sensing
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• v.34 no.6_2
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• pp.1229-1238
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• 2018

We examined if a state of sea-ice in Bering Sea acts as a prelude of variation in that of Chukchi Sea by using satellites-based Arctic sea-ice concentration time series. Datasets consist of monthly values of sea-ice concentration during 36 years (1982-2017). Time series analysis armed with Transfer entropy is performed to describe how sea-ice data in Chukchi Sea is affected by that in Bering Sea, and to explain the relationship. The transfer entropy is a measure which identifies a nonlinear coupling between two random variables or signals and estimates causality using modification of time delay. We verified this measure checked a nonlinear coupling for simulated signals. With sea-ice concentration datasets, we found that sea-ice in Bering Sea is influenced by that in Chukchi Sea 3, 5, 6 months ago through the transfer entropy measure suitable for nonlinear system. Particularly, when a sea-ice concentration of Bering Sea has a local minimum, sea ice concentration around Chukchi Sea tends to decline 5 months later with about 70% chance. This finding is considered to be a process that inflow of Pacific water through Bering strait reduces sea-ice in Chukchi Sea after lowering the concentration of sea-ice in Bering Sea. This approach based on information theory will continue to investigate a timing and time scale of interesting patterns, and thus, a coupling inherent in sea-ice concentration of two remote areas will be verified by studying ocean-atmosphere patterns or events in the period.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.12
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• pp.1063-1070
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• 2002

To resist ice adhesion on cooling wall is concerned to continuous ice formation in thermal storage system. In this study, ice slurries were formed with two ecological aqueous solution, one is ethanol+silanol and the other is propylene glycol+silanol. By freezing under stirring the solution of $300m\ell$ in a stainless steel vessel which was immersed and cooled in a temperature controlled bath, the shape of ice slurry and the strength of ice adhesion on wall was observed with measuring the temperature and stirring load variation. As the concentration is smaller and the supercooling degree is larger, the ice adhesion is easy to occur. When the stirring load is larger than$ 2.1\times10^{-5}W$, the ice adhesion occurred.

• Journal of Advanced Marine Engineering and Technology
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• v.24 no.5
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• pp.52-57
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• 2000

Recently large capacity of electric equipment and increasing in atomic power generation are shown. One of the reason is shortage of the electric power supply for air conditioning load during summer. And every consumer is concerning about economical refrigeration and air conditioning system to decreases electric power consumption and decrease in global warming. For these necessities, ice making thermal storage system is required. Therefore, in this paper, the possibility of continuous slurry ice making using flowing organic water solution in cooled circular tube has been investigated. The experiments was carried out under some parameters of concentration and velocity of water solution, temperature of cooled tube wall, and control pressure in tube, As a result, four types of operating conditions in the pipe, that was supercooling, continuous ice making, intermittent ice making and ice blockage, were classified . And it was found that the critical condition for continuous ice making was acquired as a function of these experimental parameters.

• The Korean Journal of Food & Health Convergence
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• v.9 no.5
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• pp.7-11
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• 2023

Purpose: The purpose of this study is to analyze current trends in the Korean ice cream industry and determine how these trends affect the competitiveness of each ice cream company. Method: This study was conducted by reviewing existing related literature and collecting and analyzing data from news articles, corporate reports, and existing researchers' studies related to the ice cream industry. Results: The Korean ice cream industry is growing and developing through the collaboration of fun marketing with taste, quality, and fun elements, and the young MZ generation can be said to be the main customer base. In terms of quality, premium ice cream made with high-quality domestic ingredients has recently been gaining popularity, and ice cream with reduced fat and sugar, such as plant-based substitutes, is also gaining popularity among consumers. Conclusions and Implications: The results of this study highlight the need for continued innovation in the Korean ice cream industry. The industry must also capitalize on the growth of online sales and the global appeal of Korean pop culture. Sustainability efforts, technology adoption, and strategic collaboration are key drivers for future industry success, and social media engagement must be integrated into marketing strategies to increase brand awareness and consumer loyalty.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.34.1-34.1
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• 2013

Interstellar ices (e.g., $H_2O$, $CO_2$, and CO ices) are formed on the surface of dust grains in dense molecular clouds. In a near-infrared spectrum, we can observe deep absorption features particularly due to $H_2O$ ice at $3.05{\mu}m$ and $CO_2$ ice at $4.27{\mu}m$. These interstellar ices have many pieces of information on the interstellar environment. Among various ices, $CO_2$ ice is one of the most important ones as a probe of the interstellar environment. That is because $CO_2$ ice is a secondary product unlike $H_2O$ and CO ices which are primarily formed on dust grains. Past studies for $CO_2$ ice in nearby galaxies were performed only for the galactic center in a few galaxies. In order to utilize the information from $CO_2$ ice effectively, it is valuable to perform mapping observations of ices on a galactic scale. With AKARI, we obtain the spatially-resolved near-infrared ($2.5-5.0{\mu}m$) spectra for the central ~1 kpc region of the nearby starburst galaxy M 82. These spectra clearly show the absorption features due to interstellar $H_2O$ and $CO_2$ ices, and we created their column density maps. As a result, we find that the spatial distribution of $H_2O$ ice is significantly different from that of $CO_2$ ice; $H_2O$ ice is widely distributed, while $CO_2$ ice is concentrated near the galactic center. Our result for the first time reveals spatial variations in $CO_2/H_2O$ ice abundance ratio on a galactic scale, suggesting that the ice-forming interstellar environment changes within a galaxy. In this presentation, we discuss the cause of the variations in the ice abundance ratio.

• Journal of the Society of Naval Architects of Korea
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• v.49 no.2
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• pp.189-195
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• 2012

The ice trials of the first Korean icebreaking research vessel "ARAON" were performed at the Arctic Ocean in July-August 2010. The sea ice concentrations of Arctic Ocean were 4/10 to 10/10 and the range of sea ice thickness was roughly 1.0 to 3.5m. In this research, sea ice thickness characteristics at the old ice floes were determined from results of drill hole and apparent conductivity measurements. Especially we measured apparent conductivity using an electromagnetic induction instrument (EM31-MK2) and estimated the sea ice thickness through the empirical equation from Cold Regions Research & Engineering Laboratory, CRREL. The results of estimated sea ice thickness were compared to drill hole measurement results and then, we suggest the new empirical equation to estimate sea ice thickness of single layer type sea ice during the summer season of Arctic Ocean by curve fitting approach to these data.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.5
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• pp.291-296
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• 2009

Ice accumulating system patterned ice-an-coil is the way of refrigerating regenerative materials on the surface of copper-tube inserted into the inside of ice-storage. The study experimented to understand ice-an-coil type ice making characteristics according to changing shape of ice making tube. The experiment were carried out under various conditions, that used brine temperature($-l0^{\circ}C$, $-6^{\circ}C$) brine flow rate(l.0m/s, 1.8m/s) and inlet water temperature($6^{\circ}C$, $12^{\circ}C$) etc. Mass of ice per making area increased according to the decrease of the brine temperature and inlet water temperature, but that was increased according to the increase of the brine flow rate. And I set up two hypotheses and compared the capacity of ice-making of the two cases; each had the same thermal area and one had an round-shaped copper tube but the other had an oval-shaped copper tube.

• Journal of Coastal Disaster Prevention
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• v.4 no.3
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• pp.133-137
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• 2017

The Arctic region remains surrounded by sea ice during most of the period of the year. In the Arctic Ocean the Northern Sea Route (NSR) has been used as an important route for shipping. The arctic sea ice is decreasing since 1979; hence needs to be monitored. In this research work sea ice concentration in the recent years and sea ice concentration anomalies of few months with long term sea ice concentration are studied. The climatology of long term ice concentration data from various satellites, and the recent sea ice concentration data from Advanced Microwave Scanning Radiometer 2 (AMSR2) were used. The results show that sea ice concentration and sea ice extent in the Arctic region decreased by around 5% from 2015 to 2016, but in 2017 increased again in smaller amount in some areas like around Novaya Zemlya, and parts of the sea in between Greenland and Longyearbyen, and around Banks Island. The percentages of sea ice area in NSR for July 7 in 2015 to 2017 were 37%, 39% and 33%, respectively, indicating a large area (around ten thousand $km^2$) become ice free in 2017 compared to the previous year.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.5
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• pp.392-401
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• 2009

Ice-crystal clouds observation was conducted using a GIST/ADEMRC Multi-wavelength Raman lidar system in order to measure vertical profile and optical depth at Gwangju ($35^{\circ}$10'N, $126^{\circ}$53'E), Korea in December 2002, and March and April 2003. Ice-crystal clouds at high altitude can be distinguished from atmospheric aerosols by high depolarization ratio and high altitude. Ice-crystal clouds were observed at 5~12 km altitudes with a high depolarization ratio from 0.2 to 0.5. Optical depth of ice-crystal clouds had varied from 0.14 to 1.81. The radiative effect of observed ice-crystal cloud on climate system was estimated to be negative net flux in short wavelength (0.25~$4.0{\mu}m$) and positive net flux in short+long wavelength (0.25~$100{\mu}m$) at top of the atmosphere. Net flux by ice-crys tal cloud per unit optical depth was comparable to that of Asian dust.