• Journal of the Korean Applied Science and Technology
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• v.37 no.4
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• pp.860-869
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• 2020

This study was conducted to see the effect of maintaining the freshness of mackerel caught offshore, through the chemical analysis method in seawater slurry ice(SS), sea water cube ice(SC), tap water slurry ice(TS) and tap water cube ice(TC). Among each ice mass, bacteria were below the drinking water standard and ammonia nitrogen was over the threshold of 11 mg/l in sea water. The turbidity of the seawater was severe compared to that of fresh water. Proximate compositions showed 72.7% moisture content, 20.5% protein, 5.25% lipid, and 1.3% ash content. Sea slurry ice was kept low in pH compared with fresh water ice. VBN increases were inhibited in all reservoirs at the beginning of the storage. Generally Sea ice was kept lower VBN value than the fresh water ice.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2019.10a
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• pp.217-217
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• 2019

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2019.10a
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• pp.216-216
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• 2019

• The Science & Technology
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• v.33 no.2 s.369
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• pp.84-88
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• 2000

세계의 기상관측시대는 한국으로부터 열렸다고 볼 수 있다. 1441년 세계 최초로 세종때 측우기를 개발하였기 때문이다. 새 천년을 맞아 상당수 과학자들은 대기온난화 등 미래의 지구기후에 관심을 기울이고 있다. 실제로 기온이 3℃ 상승하면서 해수면이 1m 이상 높아지고 바닷물이 지하로 흘러들어 우물이 짠물이 된다. 또 기온이 3℃ 강하하면 지상에 얼음과 눈이 누적되어 해수면이 3~6cm 낮아지고 지하수면도 낮아져 하천과 호수가 바닥을 드러내게 되어 과학자들은 크게 우려하고 있다.

• Journal of Power System Engineering
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• v.14 no.5
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• pp.76-82
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• 2010

This paper investigates the optimum operating conditions to construct total automatic control system with high energy efficiency of a newly developed seawater ice machine. The machine has an electronic expansion valve(EEV) and a variable speed rotating drum with an evaporator installed inside. The coefficient of performance(COP) was used as an index to evaluate energy efficiency of the machine. At first, the opening angle of EEV was adjusted to obtain COP of the machine at a constant speed of the drum. Then, we checked seawater ice product versus opening angles of the EEV. Finally, effect of drum's rotating speed in response to product of seawater ice and seawater ice temperature were considered.

• Journal of Advanced Marine Engineering and Technology
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• v.41 no.3
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• pp.197-201
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• 2017

Most fishing vessels use an ice cooling system to manage and store captured fish. However, it is difficult to maintain an adequate temperature and salt concentration as well as operating time limitations in ice cooling systems. The purpose of this study is to investigate the heat transfer characteristics of flooded-type evaporators for a seawater cooling system to maintain proper seawater temperature in a fish tank. Experiments were conducted to investigate the heat transfer characteristics by changing the seawater temperature, flow rate, and saturation temperature of the refrigerant. It was confirmed that the heat transfer coefficient of an aluminum-brass tube was approximately 10% higher than that of a copper-nickel tube at the same heat flux. Furthermore, it was confirmed that applying the aluminum-brass tube to the heat transfer tube of a seawater heat exchanger was effective in terms of heat transfer. A comparison of the overall heat transfer coefficient of a single-tube heat exchanger and the flooded-type multi-tube heat exchanger for an 18-kW cooling system showed that the heat transfer coefficient of the single-tube heat exchanger was 25% higher under the same conditions. These results are considered to be important data for designing a flooded-type multi-tube heat exchanger.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.4
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• pp.373-378
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• 2011

The freeze desalination cycle with seawater heat pump system is simulated and designed for the basic data for the design of freeze desalination system. The basic model of seawater heat pump system is refrigeration cycle and indirect freeze desalination method is used for seawater desalination. The cycle performance of seawater heat pump such as COP, compressor work, condensing capacity was analyzed and the desalination performance such as fresh water productivity and energy per unit fresh water productivity was compared with respect to the seawater temperature of condenser inlet and ice ratio in the evaporator. The compressor work and condensing capacity decreased with respect to the decrease of seawater inlet temperature. The energy per unit fresh water productivity in case of $8^{\circ}C$ seawater inlet temperature showed 28.9% lower than that of $20^{\circ}C$.

• 한국해양학회지
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• v.27 no.3
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• pp.250-258
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• 1992

The oxygen isotope composition of surface waters in the Bransfield Strait was determined as one extra state variable in order to characterize water masses in the region, since salinity is significantly modified due to the freezing and ice-melting in the polar region. The salinity, temperature, and $\delta$/SUP 18/O values vary from 34.0 to 34.5$\textperthousand$, -.05 to 2.1$^{\circ}C$ and -0.50 t -0.26$\textperthousand$, respectively. The combined effects of evaporation, precipitation, freezing, ice-melting are reflected in the widely scattered data. Although it is small, the distribution of $\delta$/SUP 18/O of the Bransfield Strait is strongly affected by the freezing-ice melting rather than the evaporation-precipitation. The ice melted fresh water which has higher temperature, depleted salinity and nutrients may be injected to the Bransfield Strait from the north. The concentrations of nutrients are decreasing gradually from the north to the south. The waters were characterized by two groups of higher (about 19.4) and lower N/P ratio (about 16.7). The lower N/P ratio is found in the northern part where ice-melted fresh water is injected. and the higher N/P ratio is found in the southern part of the Bransfield Strait. Although more precise work is needed, the deference of N/P ratio can be an evidence of the ice melted water injection to the Bransfield Strait. Chlorophyll a concentrations, in general, increase from northwest (Waddell Sea) to the southeast (Smith and Hosseason Islands). Probably the injection of nutrient depleted fresh water from the ice melting reduce the chlorophyll a concentration.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.109-110
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• 2003

우리 국민들은 살아서 펄떡펄떡 뛰는 활어를 조리사가 소비자가 보는 앞에서 바로 회로 처리한 것을 가장 선호하고 있으므로 양식장에서 살아 있는 상태로 활어를 수송하고 있다. 그렇지만 현재의 활어수송 방법은 활어를 운반하기 위하여 많은 량의 해수를 함께 싣고서 수송하고 있으므로 필요 없는 대량의 물을 나르게 되어 수송경비가 증가된다. 또한, 횟집에서는 활어수조 등의 시설비가 들어가며 횟집에서는 수조를 자주 청소해야 하는 단점이 있을 뿐만 아니라 수조관리를 잘못하게 되면 활어가 죽기도 한다. (중략)

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.118-118
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• 2003

홍조류 김속 해조 5종(모무늬돌김, 방사무늬김, 참김, 긴잎돌김, 잇바디돌김)의 사상체를 2단계 냉각법으로 액체질소 중에서 동결보존을 시행하였다. 시료를 여러 가지 동해보호제에 현탁시킨 후 프로그램 냉각기로 4시간에 걸쳐 -4$0^{\circ}C$까지 천천히 동결시켰다. 일차 완만동결 종결 후 즉시 동결용 튜브를 액체질소 중에 수용하여 급속동결 시켰다. 해동시에는 4$0^{\circ}C$의 항온수조에서 대부분의 얼음 결정을 급격히 해동시킨 후 냉각수내에서 완전히 해동시켰다. 생존률은 김 속 해조에서는 neutral red로 염색하여 산정하였으며 50% 해수에 10% DMSO와 0.5M sorbitol 혼합액을 동해보호제로 사용하였을 때의 생존율이 54.6~70.9%였다.