• Proceedings of the KSRS Conference
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• 1998.09a
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• pp.76-82
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• 1998

Increase of greenhouse gas due to $CO_2$ and CH$_4$ gases would cause the global warming in the atmosphere. According to the global circulation model, it is pointed out in the Okhotsk Sea that the large increase of atmospheric temperature might be occurredin this region by global warming due to the doubling of greenhouse effectgases. Therefore, it is very important to monitor the sea ice extents in the Okhotsk Sea. To improve the sea ice extents and concentration with more highly accuracy, the field experiments have begun to comparewith Airborne Microwave Radiometer (AMR) and video images installed on the aircraft (Beach-200). The sea ice concentration is generally proportional to the brightness temperature and accurate retrieval of sea ice concentration from the brightness temperature is important because of the sensitivity of multi-channel data with the amount of open water in the sea ice pack. During the field experiments of airborned AMR the multi-frequency data suggest that the sea ice concentration is slightly dependending on the sea ice types since the brightness temperature is different between the thin and small piece of sea ice floes, and a large ice flow with different surface signatures. On the basis of classification of two sea ice types, it is cleary distinguished between the thin ice and the large ice floe in the scatter plot of 36.5 and 89.0GHz, but it does not become to make clear of the scatter plot of 18.7 and 36.5GHz Two algorithms that have been used for deriving sea ice concentrations from airbomed multi-channel data are compared. One is the NASA Team Algorithm and the other is the Bootstrap Algorithm. Intrercomparison on both algorithms with the airborned data and sea ice concentration derived from video images bas shown that the Bootstrap Algorithm is more consistent with the binary maps of video images.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.578-584
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• 2013

Ice slurry that is a mixture of fine ice crystals and liquid water is a widely used working fluid in the ice thermal energy storage system due to its flowability and large latent heat of fusion. Generally ice slurry is made from supercooled water. But the excessive supercooling causes the water to freeze even worse to block the pipe. Additionally large degree of supercooling of water degrades the efficiency of the ice thermal energy storage system. Therefore the effective method to control the phase change from supercooled water to ice slurry is needed. In this paper we experimentally studied a novel method to generate the ice slurry from the supercooled water using the ultrasonic vibration. It was found that the cavitation impact of supercooled water by ultrasonic vibration can help the generation of ice slurry.

• Journal of Power System Engineering
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• v.21 no.2
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• pp.77-82
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• 2017

In the fishing boat, freshwater ice is loaded on the fishroom in advance and it is used for storage of fishes. However, it causes degradation of catches' freshness. Therefore, seawater ice machine on board is necessary for the fishing industry. In this study, seawater ice machine with drum type evaporator was manufactured, and the system was tested under various operating conditions having an influence on the COP and amount of ice produced. The main results are as follow : The COP of the system gets larger when the evaporation temperature and rotation speed of the drum in the evaporator increases. The most effective refrigerant is R22 and the value of the COP was 1.43 times higher than that of R404A. The amount of produced ice increases with respect to increment of the evaporation temperature, while that decreases with respect to increment of the evaporator drum rotation speed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.12
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• pp.1835-1845
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• 2021

To accurately identify black ice and warn the drivers of information in advance so they can control speed and take preventive measures. In this paper, we propose a lightweight black ice detection network based on infrared road images. A black ice recognition network model based on CNN transfer learning has been developed. Additionally, to further improve the accuracy of black ice recognition, an enhanced lightweight network based on MobileNetV2 has been developed. To reduce the amount of calculation, linear bottlenecks and inverse residuals was used, and four bottleneck groups were used. At the same time, to improve the recognition rate of the model, each bottleneck group was connected to a 3×3 convolutional layer to enhance regional feature extraction and increase the number of feature maps. Finally, a black ice recognition experiment was performed on the constructed infrared road black ice dataset. The network model proposed in this paper had an accurate recognition rate of 99.07% for black ice.

• Journal of Food Hygiene and Safety
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• v.30 no.4
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• pp.309-314
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• 2015

The purpose of this study is to monitor the microbial contamination of ice collected from food stores or restaurants from all over the country. From the ice collected on a regional basis, it was observed that the average number of total aerobic bacteria (TAB) of samples from Seoul was the highest, showing 2.31 log CFU/g, while that of samples from Jeolla-do was the lowest, showing 1.83 log CFU/g. The food-borne pathogens (Staphylococcus aureus, Listeria monocytogenes) were not detected from the ice. Also the average number of TAB of packaged ice (commercial ice) was 0.45 log CFU/g lower than that of ice from ice-making machine. Among three types of stores (the bakery, the dessert store and the beverage store), ice from dessert store showed the highest number of TAB (2.37 log CFU/g). This study suggests that the hygienic management of the ice from the stores is necessary. Therefore, to ensure the hygienic management of ice, not only the ice-making machine should be sanitized on a regular basis but also a thorough individual hygiene is required from food manufacturing workers.

• Journal of the korean society of oceanography
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• v.34 no.2
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• pp.59-72
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• 1999

Cavitating fluid sea ice model of Plato and Hibler (1992) is applied to the Southern Ocean with an idealized, circular Antarctica. Using climatological atmospheric forcing fields averaged in the zonal direction, we show that oceanic heat flux and ice velocity have major effects on the seasonal change of ice edge, as other studies showed. In our model results, there appears a zone of free drift that contains a polynya zone. Thermodynamic forcing functions make dominant contributions to daily increments of ice thickness and compactness, except the zones of ice edge and polynya. The dominant contributions are also shown in distributions of the temperature on ice surface and several to terms in surface heat balance equation, and are also confirmed by those obtained from the thermodynamic-only model with the different locations of ice edge.

• International Journal of Naval Architecture and Ocean Engineering
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• v.10 no.3
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• pp.403-412
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• 2018

Medium-scale tests were conducted to measure and observe the strength and failure behavior of freshwater ice rubble. A custom box measuring $3.05m{\times}0.94m{\times}0.94m$, with Plexiglas walls was built so that failure mechanisms could be observed. Ice rubble beams of nominal thickness 50 cm were produced by placing randomly sized ice pieces into the box filled with water at its freezing temperature. After the specified consolidation time, ranging between 0.2 and 70.5 h, the ice rubble beam was deformed by pushing a platen vertically downwards though the center of the beam until failure. For consolidation times less than 4 h, the ice beam failed progressively and tended to fail by shearing on macroscopic scale. At times greater than 4 h the beam failed by bending. The change in failure behaviour has been attributed to the degree of bonding between ice blocks.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1996.10b
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• pp.193-205
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• 1996

This paper deals with experimental study on thermal characteristics that a cooling fluid is affected to ice ball as being measuring the temperature in storage tank and ice ball governing the rate of heat storage. Distributor was taken as inlet geometry factor. flow rate of cooling fluid which was a brine were 2, 4, and 6LPM, and 8, 10, and 12$^{\circ}C$ in the temperature difference for dynamic factors with respect to three ice ball types(103, 96, 76mm). In case of in flowing cooling fluid, since inertia force is suppressed by lower flow rate the amount of heat was transferred to ice ball by heat conduction high because density difference is high. And in case of larger ice ball, a long-term storage was available because reaching time at steady state is relatively long. consequently, smaller ice ball could be suitable to a short-term storage.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2011.06a
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• pp.379-381
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• 2011

2010년 3월 22일 "Ice Navigation"에 대한 경험과 자료 수집을 위하여 통영항(평택항)과 Sakhalin "Prigorodnoye항"을 운항하는 대한해운 소속의 "K. Jasmine"호를 승선하여 "Prigorodnoye항"에서 LNG $143,700M^3$를 선적하여 "통영항"에서 양하하는 과정을 경험하고 하선하였다. "K. Jasmine"호는 년 150만톤의 LNG 수입을 위한 "한국 ${\leftrightarrow}$ Sakhalin Project"에 투입된 LNG운반선으로서 "Russian Maritime Register of Shipping"의 "Ice Class LU2" 증서를 갖고 있는 선박이다. 이 증서는 선박이 60Cm 두께의 얼음 해역에서 Ice Breaker의 인도 아래 4Knots 이상의 선속을 유지할 수 있음을 보장받고 있다. 운항중 SEIC(Sakhalin Energy Investment Company)에서는 Ice map을 매일 제공하는 하고 있었으며, 이를 참조하여 본선에서는 계획된 항해를 수행하였다. 이 논문에서는 Ice Navigation선박의 성능 조건에 대하여 검토하여 향후 이 항로에 취항하는 선박에 지침이 되고자 한다.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.1 no.1
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• pp.37-49
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• 1994

The purpose of this study was to measure the oral temperature, skin temperature, and subjective discomfort according to the application time of ice bag on thigh, head, and abdomen. This study was also intended to suggest nursing principles about ice bag application by exploring the recovery time of skin temperature after the removal of ice bag. The design of this study was $8{\times}3$ factorial design with one sample repeated measure. Here, the application time of ice bag(criteria, 5min, 10min, 20min, 30min, 40min, 50min, 60min) and the application site of ice bag(thigh, head, abdomen) were independent variables. The subjects were 10 university woman students, and data collection was made from July, 1 to August 30, 1992. Rubber ice bag halfly filled with ice was covered with towel and applied on thigh, head and abdomen in other three days. Before applying the ice bag, oral temperature and skin temperature were checked for criteria. After ice bag was applied, skin temperature, oral temperature and VAS score were checked at first 5 minutes elapsed, and every 10 minutes until 60 minutes. After that, ice bag was removed, and oral temperature and skin temperature were also measured every ten minutes until 60 minutes. In this study, skin temperature and core temperature were measured by thermistor probe, and subjective discomfort was measured by 200mm VAS (Visual Analogue Scale). Some of the findings were as follows : 1. There were significant differences in skin temperature among the three application sites of ice bag as time go by. It was most decreased to $15.87^{\circ}C$ in thigh, and $19.47^{\circ}C$ in abdomen at 50 minutes after the application of ice bag, whereas $26.1^{\circ}C$ at 40 minutes in head. Before the application of ice bag, skin temperature showed significant differences in three sites, so that they were compared after the criteria was covariated. In other words, there was significantly more decrease of skin temperature in thigh and abdomen than head, after ice bag was applied for 20 minutes and more. 2. There was no significant difference in core temperature among the three application sites of ice bag during the time of application 3. There was no significant difference in subjective discomfort (VAS) among the three application sites of ice bag. 4. After the removal of ice bag, the recovery of skin temperature was significantly different in three sites during first 30 minutes. In head, skin temperature came up to criteria at 30 minutes after the removal of ice bag, but it was not recovered In thigh and abdomen even 60 minutes elapsed. 5. After the removal of ice bag, there was no significant difference in oral temperature among the three application sites of ice bag. 6. There was significant correlation between the skin temperature and VAS score only in thigh. In conclusion, it is suggested that head in more suitable site for the application of ice bag if it is used for the relief of fever or pain. When we apply ice bag on thigh or abdomen for the relief of pain, careful attention is required.