• Journal of Advanced Marine Engineering and Technology
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• v.37 no.1
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• pp.9-15
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• 2013

The effective use and management of energy resources has been issued to solve the global warming problem and petrolium price increase. To improve the energy efficiency of a heat exchanger, a new countermeasure is required and the heat transfer research of nano-fluids as a new working fluid is needed. This study was carried out with increasing the Reynolds number and the vol% of nano-fluids in the inlet temperature of $25^{\circ}C$ and $50^{\circ}C$. As the result, the higher the entrance temperature is, the higher the convective heat transfer coefficient is.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.21-24
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• 2008

We have developed a $kW_e$ class liquid fuel based solid oxide fuel cell (SOFC) system. Our final target is to develop the 1 $kW_e$ diesel based SOFC system for residential power generator(RPG). In this study, we present the conceptual design of SOFC system. System is composed of hot-box and cold-box. Planar typed SOFC stack, heat exchanger, combustor for stack tail gas, and fuel processor, such as fuel reformer and desulfurizer, are contained in the hot-box. And several balance of plants(BOP), such as fuel suppliers and controller, are contained in the cold-box. Before the SOFC system fabrication, we have already operated the selfsustaining fuel processor, and heat exchange of all heat-related components is simulated using ASPEN HYSYS, because heat maintenance and management in hot-box are important for stable operation of SOFC system. The self-sustained fuel processor was successfully operated for about 250 hours, and heat exchange is enough to operate the SOFC system.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.38.2-38.2
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• 2005

• Proceedings of the Korean Nuclear Society Conference
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• 2003.05a
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• pp.383.1-383.1
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• 2003

• Journal of the Korea Convergence Society
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• v.10 no.7
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• pp.281-287
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• 2019

Application of heat recovery system applying air supply and cexhaust ventilation device essential in energy management system for the optimum ventilation system utilization and energy saving. This is a key element of infrastructure technology for high-efficiency energy buildings, because it can save heating and cooling energy in winter and summer. In this paper, heat transfer efficiency was simulated using paper, plastic, and aluminum materials that was examined to compare heat exchanger performance under uniform flow conditions. We tested heat transfer efficiengy according to the shape of two of that, one is orthogonal and the other is refraction shape. Based on the simulation results, it is expected to contribute to the production of high performance heat exchanger with heat transfer performance and pressure loss.

• Journal of Industrial Convergence
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• v.18 no.6
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• pp.99-105
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• 2020

In general, heat-based treatments are preferred to form the most natural and elastic curls. Therefore, this study measured the degree of hair damage, which has an influence on hair, in relation to the heat formation of the rods used during perms using a scanning electron microscope (SEM). To examine the influence of the heat formation rods on permanent waves, this study measured the temperature transmitted from such rods. Then, a treatment was given after cutting the hair according to the round shape. According to observation with a SEM, hair breakage was found in the portion in direct contact with the heat, and the broken surface was smooth. According to the study results, it is anticipated that there should be many studies on the rods used during perms in the consideration of their structure and importance using materials that have the property of even heat transmission.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.10
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• pp.1422-1428
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• 2000

This investigation was conducted to evaluate the shrimp flesh (SF) and shrimp by-product (SB) of the most abundant shrimp species (Metapenaeus affinis, Penaeus semisulcatus and Penaeus monodon) caught in Central Vietnam, with the emphasis on yield, gross and amino acid (AA) composition and effect of heat treatment. The results showed that the mean edible SF and SB (head and shells with tail) yields of the three shrimp species averaged 56.7 and 43.3%, respectively, of the total wet body weight, with the M. affinis generating the highest by-product yield (45.7%) and P. semisulcatus (40.6%) the lowest. Significant differences in dry matter (DM), crude protein (CP) and ash content were found between SF and SB. The DM content of SF (21.5%) was lower than of SB (24.9%) and the ash content (on a DM basis) of the SB in all shrimp species was more than three times that of the SF (p<0.05), whereas the CP content was almost twice as high in the SF as compared with the SB (p<0.05). The SB of the three species contained (on a DM basis) between 44.0 and 49.8% CP (p<0.05) and between 13.5 and 18.1% chitin (p<0.05). The Ca content of SB differed also between species (p<0.05). On average, the sum of AA in SB corresponded to 89.3% of the CP and essential AA accounted for about 50% of the total AA. The most abundant AA were arginine, aspartic and glutamic acids, which accounted for 33% of the total AA. Minor, but significant differences in some AA concentrations of SB between species were observed (p<0.05). With the exception of the DM and ether extract content, all other chemical constituents of entire shrimp, SF and SB were not significantly affected by heat treatment (p>0.05).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.10
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• pp.4308-4313
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• 2011

The objective of this study is to investigate the cooling performance of the roof mounted air-conditioning system using electric driven scroll compressor for zero emission vehicles. This air conditioner with air source was used R-134a as a refrigerant and tested under various operating conditions such as refrigerant charge amount and indoor temperature, and compressor frequencies. Experimental results revealed that at all tested compressor frequencies, heat transfer rate of the evaporator increased and the cooling COP increased with the indoor temperature. In addition, the heat transfer rate of the evaporator was over 25.0kW sufficient for the cooling loads of an electric bus.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.5
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• pp.2545-2552
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• 2014

This study is aiming to suggest the effective thermal management system design technologies for the high voltage and capacity battery system of the electricity driven vehicles and introduce the theoretical designing methods. In order to investigate the effective operation of the battery system for the electricity driven vehicles, the heat generation model for Li-ion battery system using the chemical reaction while charging and discharging was suggested and the thermal loads of the heat sources (air or liquid) for cooling and heating were calculated using energy balance. Especially, the design methods for the cooling and heating of the battery system for maintaining the optimum operation temperature were investigated under heating, cooling and generated heat (during charging and discharging) conditions. The battery thermal management system for the effective battery operation of the electricity driven vehicles was suggested reasonably depending on the variation of the season and operation conditions. In addition, at the same conditions under summer season, the cooling method using the liquid and active cooling technique showed a relatively high capacity, while cooling method using the passive cooling technique showed a relatively low capacity.

• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.5
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• pp.486-493
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• 2015

In this paper, a battery model for electric vehicle virtual platform was developed. A battery model consisted of a battery cell model and battery thermal management system. A battery cell model was developed based on Randles equivalent circuit model. Circuit parameters in the form of 3D map data was obtained by charge-discharge experiment of Li-Polymer battery in various temperature condition. The developed battery cell model was experimentally verified by comparing voltages. Thermal management system model was also developed using heat generator, heat transfer and convection model, and cooling fan. For verification of the developed battery model in vehicle level, the integrated battery model was applied in to EV(electric vehicle) virtual platform, and virtual driving simulation using UDDS velocity profile was conducted. The accuracy of the developed battery model has been verified by comparing the simulation results from EV platform with the experimental data.