• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.6
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• pp.319-325
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• 2009

The purpose of this study is to investigate the performance characteristics of a bypass two-circuit refrigerator. A bench scale refrigeration system was designed and constructed to estimate possible performance improvement of the bypass two-circuit refrigerator. The experiments were conducted in the bench scale refrigeration system by varying capacity of the condenser and refrigerant charge amount with an adoption of a refrigerant storage vessel. The COPs of the bypass two-circuit refrigeration system in the refrigerator and freezer (RF)-mode and freezer(F) only-mode were increased by 10% and 17%, respectively, with increasing the capacity of the condenser. Besides, the COP of the system in the F only-mode was increased by 10% by adopting the refrigerant storage vessel.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.833-834
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.611-612
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• 2012

• Journal of the Korea Safety Management & Science
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• v.4 no.3
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• pp.35-43
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• 2002

For the unconfined vapor cloud explosion accident by the continuous release of gas-liquid flow of various saturated liquids in a vessel at ground level, overpressures were estimated and analyzed with various release conditions and materials by TNT equivalency model with vapor dispersion. We found that at same release conditions, overpressure showed n-heptane > xylene > n-hexane > toluene > n-heptane > benzene, respectively and that overpressure was increased with increasing the hole diameter and the storage pressure, but it was increased with decreasing the wind speed, the interested distance, and the vessel thickness.

• Proceedings of the Korean Nuclear Society Conference
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• 2001.05a
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• pp.389-389
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• 2001

• Proceedings of the Korean Nuclear Society Conference
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• 2001.10a
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• pp.292.2-292
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• 2001

• Korean journal of food and cookery science
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• v.28 no.2
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• pp.207-214
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• 2012

In this study, cabbage ($Brassica$ $oleracea$ var. $capitata$) Kimchi was made packed into four kinds of packaging materials, PET vessel, PP tray, OPP/AL/PE film and Nylon/PE/LLDP film, and the effects of these packaging materials on Kimchi quality characteristics, such as lactic acid bacteria counts, salinity, sugar contents, pH, total acidity, electron donating ability were examine as well as their effects on the sensory qualities after storage at a temperature of $4^{\circ}C$. The pH change ranged from pH 6.24 to 6.43 shortly after manufacture, and did not significantly change until 7 days of storage. However, it began to decrease rapidly after 14 days. On the 35th day of storage, the acidity was 0.79% in the PET vessel and 0.83% in OPP/AL/PE. Therefore, the PET vessel and OPP/AL/PE were considered appropriate packaging materials for Kimchi storage. The salinity did not change significantly during the storage period, and the sugar content generally increased in the four kinds of packaging materials, but decreasing after the 7th day of storage. After 14 days of storage, the Kimchi stored in the OPP/AL/PE film showed the highest lactic acid bacteria counts. Although the electron donating ability was the highest after proper time for fermentation, it decreased in all the packaging materials after the proper time for fermentation. However, the OPP/AL/PE film had an antioxidant potential of up to 93.18%. In the sensory evaluation, fermented Kimchi was found to be superior unfermented Kimchi. In addition, the Kimchi stored in the OPP/AL/PE film for 14 days showed the high score of 6.70 and 6.60 in overall preference. Therefore, the results of this study provide basic knowledge on the fermentation level and packaging material's condition for commercialization of small packed cabbage Kimchi. Henceforth, industrialization must include a variety of studies under these conditions to increase the merchantability.

• Transactions of the Korean hydrogen and new energy society
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• v.35 no.2
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• pp.195-204
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• 2024

The study involves a finite element analysis to evaluate the structural integrity of the neck mount block for a type 4 hydrogen storage vessel, with the aim of enhancing its strength and rigidity. The existing neck mount block consists of a fixed part and a sliding part, each comprising a body block for load support, a screw part for neck boss fixation, and bolts. To analyze the vulnerabilities of the neck mount block under bolt fastening and load conditions relative to vehicle travel directions, a structural analysis process was developed. Comparative analysis between the enhanced design and the existing model was performed, resulting in improved strength and rigidity. The objective is to provide guidance for the current product development and to offer fundamental data for the design and structural analysis of future development projects.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.4
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• pp.466-475
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• 2010

This study intends to present a direction for the better reforming of fishers'onboard living conditions and proposals for preparing for ratification of the Work in Fishing Convention by means of making a comparison between standards on recent national fishing vessel accommodation facilities and standards on the Work in Fishing Convention and Its Recommendation, 2007, ILO. For the most part of standards on national fishing vessel accommodation facilities are somewhat insufficient to satisfy the provisions in Annex III of the Convention. Considering by items on fishing vessel accommodation facilities, the standards on insect protector, noise and vibration, heating and air conditioning, lighting, persons per sleeping room, recreational facility are not provided in national law. Headroom, separation of accommodation, sleeping room floor area, mattress size, mess room, galley and food storage are partially sufficient for the Convention. In case of sanitary facilities, national standards are not sufficient for the Convention. The other side, facilities related safety of ship and crew such as emergency escape etc., are fully sufficient for the Convention. These insufficiencies caused by different types of fishing vessel depend on originality of fishing method and practices. In the comparison between equivalent tonnage about vessel's length on convention and calculated tonnage of national existing fishing vessel, the difference are 226tons about length 24m and 501tons about length 45m. For that reason, headroom, persons per sleeping room, cabin of sicker and injured, sanitary facilities may decide to use gross tonnage in place of length (L) and the alleviating measure basis of convention. But in case of standards on sanitary facilities which are unsufficient for the Convention, specially in coastal fishing vessel length basis should be adopted with alleviating basis for less than length 24m.

• Industrial Engineering and Management Systems
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• v.11 no.3
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• pp.276-287
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• 2012

Determining storage locations of containers is an important issue for efficient operation of container terminals. This study assumes a storage yard with a horizontal layout in which blocks are laid out in parallel to the quay and trucks enter at the side of a block to deliver (receive) a container to (from) the yard crane. Various storage rules for determining storage locations of containers are introduced. Simulation studies are conducted for evaluating various rules. The following guidelines are derived from the result of our simulation study: when designing a block, consider a block configuration in which the longest gantry and the longest trolley travel times of rail-mounted gantry cranes (RMGCs) are similar; do not restrict the types of containers that can be stored in a storage area; if different roles are to be assigned to different storage areas, one possible way is to divide a bay into two areas so that some rows in the bay are allocated to inbound containers while the other rows in the same bay are allocated to outbound containers; reserve the space in bay unit for a high productivity of RMGCs but reserve the space in stack unit when the storage space is not enough; when the storage space is not sufficient, allocate storage location in a way of starting from the end and ending at the middle of a block; for reducing the travel distance of internal trucks, provide a higher priority to a block nearer to the berthing position of the corresponding vessel.