• Journal of Advanced Marine Engineering and Technology
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• v.39 no.10
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• pp.1002-1010
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• 2015

Natural gas hydrates are newly emerging as an environment-friendly source of energy to substitute for fossil fuels in the 21stcentury.NGHs are reported to holds much amounts of natural gas (up to 182 standard volumes of gas per volume of hydrate); they are easy to store and safe to carry at about minus 20 degree Celsius under atmospheric pressure because of the self-preservation phenomenon of gas hydrates. The transporting method by gas-ice-hydrate ship carriers has been introduced and developed by a variety of industry and research institutions. Our team has been conducted to develop NGH total systems, including a breakthrough NGH carrier for sea transportation, since 2011. The NGH pellet carrier does not require a separate cooling system for cargo, and the initial temperature is maintained through insulation of the cargo tanks throughout the transport to the final destination. The heat conducted from the exterior and passing through the insulation material of the hull should be cut off as much as possible, but heat inflow inside the cargo tank from an external source is inevitable during transport. In this study, the heat transfer in a cargo tank of a 115K NGH carrier was analyzed through simulation with a commercial CFD code to estimate the boil-off gas/boil-off rate on the developed carrier and understand major hazards that could significantly impact the safety of the vessel.

• Journal of Mushroom
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• v.9 no.1
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• pp.44-47
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• 2011

This study was carried out investigate optimal additive content of spent medium from oyster mushroom in Volvariella volvacea cultivation. The formation of spent mushroom medium from oyster mushroom consisted of 50% pine sawdust, 30% beet pulp and 20% cotton seed hull pellet. The higher amount of spent medium from oyster mushroom resulted in higher total nitrogen content and C/N ratio of medium decreased according to increasing mixing ratio of spent medium from oyster mushroom. The fruit body yield and biological efficiency of supplemented with 50% spent medium from oyster mushroom was same level of non additive medium.