• Journal of Advanced Marine Engineering and Technology
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• v.25 no.6
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• pp.1317-1323
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• 2001

The circumstance is giving the blow against fishermen with the incoming-decreasing and the difficulty of crew's supply & demand and management. In addition, the depression of the external situation like the departure of WTO system and the plan of EEZ proclaim is forcing fishery into improving their fishing condition. By this international and domestic circumstance, development of the sea water cooling apparatus for fish hold storage is demanded sincerely. First of all, we Investigated load characteristics which based on development of sea water cooling system and optimum fish hold storage. The experimental results is as follows. In creasing the speed of compressor and mass blew rate of refrigerant, the temperature of NaCl solution is low. And the load characteristics experiment on fish hold storage outlet is as fellows. As time goes by, increasing the mass flow rate of NaCl solution, temperature difference between inlet and outlet is small in a model of fish hold storage. These results provide many useful informations applicable to an actual design of sea water cooling system and optimum fish hold storage.

• Journal of Korean Society on Water Environment
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• v.20 no.6
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• pp.692-697
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• 2004

Biological phosphorus removal is characterized by complex interactions between different intracellular components of energy as PHA. Therefore, fundamental understanding of the behavior of the intracellular components and their influence on the removal of phosphorus is essential before control strategies to stabilize the proper process. The purpose of this study is to investigate relationship between release of phosphorus and synthesis of intracellular storage polymer. Mass of stored intracellular storage polymer was 21.2 mg PHA/L, 28.8 mg PHA/g MLSS. And phosphorus release/intracellular storage polymer synthesis rate was 1.8545 mg stored polymer/mg Phosphate. In the aerobic phase, mass of PAOs synthesis is 49.37 mg PAOs/L. And PAOs fraction was 6.7-6.9%. Thus intracellular storage polymer synthesis by PAOs is calculated as 493mg PHA/g PAOs.

• Water for future
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• v.18 no.3
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• pp.253-264
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• 1985

Basically, there are two ways viewing the reservoir storage-yield relationship., The most common viewpoint is the determination of the storage required at a given reservoir to supply a required yield. This type of problem is usually encountered in the planning and early design phases of a reservoir. The second viewpoint is the determination of yield from a given amount of storage. This often occurs in the final design phases or in re-evaluation of an existing reservoir for a more comprehensive analysis. The purpose of this study is to improve the present methodology estimating the storage-yield relationship for a reservoir design or a reservoir operation. The Residual Mass curve Technique, the slightly modified version of Low Flow Techniques and the Transition Probability Matrix Technique are reviewed and examined for the best fit technique to find the reservoir storage-yield realtionship. The historical data during 1917~1940 at the proposed Hongchun damsite and the synthetic data simulated by Thomas-Fiering model are utilized to examine the reservoir storge-yield relationship with three techniques in detail. After the three techniques which estimate the reservoir storage-yield relationship were reviewed extensively, it was concluded that the Residual Mass Curve Technique and the slightly modified version of Low Flow Techniques were suitable for a preliminary design, but the Transition Probability Matrix Technique Provided satisfactory results as a final design technique because it reflected the variation of a monthly yield as well as seasonlly.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.1
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• pp.202-211
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• 1995

Heat and hydrogen transfer characteristics have been experimentally investigated for a hydride reaction bed, in which hydride material LaN $i_{4,7}$A $l_{0.3}$ is contained for hydrogen storage. This problem is of particular interest in the design of metal hydride devices such as metal-hydride refrigerators, heat pumps, or metal-hydride storage units. Transient behavior of hydrogen transfer through the hydride materials as well as heat transfer is studied during absorption and desorption processes in detail. The experimental results obtained indicate that the mass flow of the hydrogen is strongly affected by the governing parameters, such as the initial pressure of the reaction bed, absorption or desorption period, and cooling or heating temperature. These mass transfer results are along with the heat transfer rate between hydride materials and heat transfer medium in the reaction bed.d.d.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.04a
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• pp.275-283
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• 1999

To predict the dynamic behavior of the cylindrical liquid storage tank subjected to seismic ground motion three dimesional analysis with liquid-structure interaction must be performed, In this study a three dimensional dynamic analysis method over the frequency domain using FE-BE coupling technique which combines the efficiency of the boundary elements for liquid with the versatility of the finite shell elements for tank. The liquid region is modeled using boundary elements which can counter the sloshing effect at free surface and the structure region the tank itself is modeled using the degenerated finite shell elements. At the beginning of the procedure the equivalent mass matrix of the liquid is generated by boundary elements procedure. Then this equivalent mass matrix is combined with the mass matrix of the structure to produce the global mass matrix in the equation of the motion of fluid-structure interaction problem In order to demonstrate the accuracy and validity of the developed method the numerical results re compared with the previous studies. Finally the effects of the fluid-structure interaction on the natural frequency and dynamic response of the system are analyzed.

• Journal of the Korean Institute of Gas
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• v.14 no.6
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• pp.27-30
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• 2010

This paper presents the system design process of district community cooling system using LNG cold energy. The newly developed LNG cooling system includes several heat exchangers, LNG storage tank, thermal mass storage tank, several cold energy storage tanks, gas air-conditioners, compressors, constant pressure regulators, cold energy and hot energy supply pipes. In addition, the gas air-conditioner system is installed to supply not sufficient cold energy due to low level of city gas consumptions during a summer period. This system design is very effective and safe to supply cold energy mass of fresh air by exchanging two thermal masses of an air and 200kcal/kg cold energy of LNG. The district community cooling system with LNG cold energy does not produce CO2 and freon gases in the air.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.11
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• pp.1330-1336
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• 2019

As the Fourth Industrial Revolution era began, a variety of devices are running on the cloud. These various devices continue to generate various types of data or large amounts of multimedia data. To handle this situation, a large amount of storage is required, and big data technology is required to process stored data and obtain accurate information. NAS (Network Attached Storage) or SAN (Storage Area Network) technology is typically used to build high-speed, high-capacity storage in a network-based environment. In this paper, we propose a method to construct a mass storage device using Network-DAS which is an extension technology of DAS (Direct Attached Storage). Benchmark experiments were performed to verify the scalability of the storage system with 76 HDD. Experimental results show that the proposed high performance mass storage system is scalable and reliable.

• Korean Chemical Engineering Research
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• v.49 no.5
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• pp.644-651
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• 2011

Storing hydrogen in solid state hydride is one of the best promising methods for the future hydrogen economy. The total performance of such systems depends on the rate at which the amount of mass and heat migration is supplied to solid hydride. Therefore, an accurate modeling of the heat and mass transfer is of prime importance in optimizing the design of such systems. In this work, Hydrogen storage in Pt-CNTs hydrogen reactor has been intensively investigated by solving 2 dimensional mathematical models. Using a CFD computer software, systematic studies have been performed to elucidate the effect of heat and mass transfer during hydrogen charging periods. It was revealed that the optimized design of hydrogen storage vessel can prevent the increase of system temperature and the charging time due to the convective cooling effects inside the vessels at even high charging pressure. Because none has reported the critical issues of heat and mass transfer for CNT based hydrogen storage system, this work can support the first insight of the optimal design for solid state hydrogen storage system based on CNT in the near future.

• Nuclear Engineering and Technology
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• v.50 no.5
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• pp.717-723
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• 2018

Thermal analysis of accident conditions is an important problem during safety assessment of the dry spent nuclear fuel storage facilities. Thermal aspects of accident conditions with channel blockage of ventilated storage containers are considered in this article. Analysis of flow structure inside ventilated containers is carried out by numerical simulation. The main mechanisms of heat and mass transfer, which take part in spent nuclear fuel cooling, were detected. Classification of accidents on the basis of their influence on the maximum temperatures inside storage casks is proposed.

• Journal of Hydrogen and New Energy
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• v.21 no.4
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• pp.249-257
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• 2010

In this paper, a three-dimensional hydrogen absorption model is developed to precisely study hydrogen absorption reaction and resultant heat and mass transport phenomena in metal hydride hydrogen storage vessels. The 3D model is first experimentally validated against the temperature evolution data available in the literature. In addition to model validation, the detailed simulation results shows that at the initial absorption stage, the vessel temperature and H/M ratio distributions are uniform throughout the entire vessel, indicating that the hydrogen absorption is so efficient during the early hydriding process and thus local cooling effect is not influential. On the other hand, nonuniform distributions are predicted at the latter absorption stage, which is mainly due to different degrees of cooling between the vessel wall and core regions. This numerical study provides the fundamental understanding of detailed heat and mass transfer phenomena during hydrogen absorption process and further indicates that efficient design of storage vessel and cooling system is critical to achieve fast hydrogen charging and high hydrogen storage efficiency.