• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.4
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• pp.567-573
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• 2003

Surimi yields from acid and alkaline processing of 5 fishes were compared to those from conventional processing Effect of sarcoplasmic protein and NaCl on heating gel from acid and alkaline surimi were also investigated by punch test and color. Yield of alkaline surimi was higher than that of conventional surimi. However, the breaking force, deformation and whiteness of heating gel from alkaline surimi were lower than those of heating gel from conventional surimi. The sarcoplasmic protein increased a breaking force and a deformation of gel. A breaking force was decreased, but deformation not significantly with NaCl concentration. Myosin heavy chain (MHC) and actin were greatly degraded in acid processing. Alkaline process for surimi is a valuable way of increasing the utilization of frozen and pelagic fishes, and making kamaboko-type products.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.688-692
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• 2005

Importance of substitute energy has been increasing due to environmental issues and lack of fossil fuels. In addition, heating cost that occupies from 30 to $40\%$ of the total production cost in Korean protected cultivation needs to be reduced for profitability and global competition. But, studying on substitute energy to solve these problems has not been activated for Korean protected cultivation. Therefore, this study was conducted to develop a geothermal heat pump system for cool ing and heat ing of greenhouses at a lower cost than conventional hot air heater and air conditioner. Fundamental test of heat transfer characteristics in soil was conducted by computer simulation and controlled tests for its verification. Based on the results of the theoretical and empirical investigations, an optimum heat pump system was developed and the performance was evaluated for practical use in a greenhouse at the Pusan Horticultural Experiment Station. The system was compared with a conventional hot air heating system through a cucumber growing test and economic feasibility analysis. Results of the application test of the geothermal heat pump showed that with an initial setting of $15^{\circ}C$ the inside temperature of the greenhouse could be maintained between 15 and $17^{\circ}C$. Results of the cucumber growing test showed that there were no significant differences in average height, leaf length, leaf width, number of nods, leaf area, dry weight and yield between the plots wi th the geothermal heat pump system and a conventional hot air heater. Economic feasibility analysis indicated that the variable cost of the hot air heater could be saved $81.2\%$ using the geothermal heat pump system. It was concluded that the geothermal heat pump system might be a pertinent heating and cooling system for greenhouses because of the low operating cost and the use of environment-friendly geothermal energy.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.1
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• pp.117-123
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• 2010

Proposed induction-heated system is innovative system which applied special high-frequency power circuit technique for thermal converse technique and IH(Induction-Heating) magnetic induction heating generated from induction-heated metallic package that is for distillation unit. This electromagnetic induction heating technique is used high frequency inverter. By using high frequency inverter high frequency alternative current in the range of [kHz] can be made with conventional alternative current. In this contribution IGBT module is used for high frequency inverter. Resonant high frequency inverter make system of high capacity and high efficiency. This paper describes the temperature control of induction heating system hot air producer using the voltage-fed series resonant high-frequency inverter which can operate in the frequency range from 20 to 44[kHz].

• Journal of the Korean Solar Energy Society
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• v.35 no.5
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• pp.49-56
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• 2015

In this study a hybrid heating system based on geothermal source and solar heat was developed in order to save energy for greenhouse heating and its field performance was evaluated. Developed system are composed of following parts: water tank, heat exchanger, heat pump, fan coil unit and heat storage unit. The working performance test was carried out in a greenhouse cultivating oriental orchids being managed by $23^{\circ}C$. Field performance test results showed that average heating coefficient of performance ($COP_h$) was 3.4 for the period from mid-January to mid-March 2013. Heating coefficient of performance ($COP_h$) of developed hybrid heat pump system was more sensitive to water tank temperature than outside air temperature. This study showed that developed hybrid heat pump system has a potential to save the heating costs up to 91% compared to conventional agricultural oil heaters.

• Transactions of Materials Processing
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• v.16 no.4 s.94
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• pp.282-287
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• 2007

Hot embossing, one of Nanoimprint Lithography(NIL) techniques, has been getting attention as an alternative candidate of next generation patterning technologies by the advantages of simplicity and low cost compared to conventional photolithographies. A typical hot embossing usually, however, takes more than ten minutes for one cycle of the process because of a long thermal cycling. Over the last few years a number of studies have been made to reduce the cycle time for hot embossing or similar patterning processes. The target of this research is to develop an induction heating apparatus for heating a metallic micro patterning mold at very high speed with the large-area uniformity of temperature distribution. It was found that a 0.5 mm-thick nickel mold can be heated from $25^{\circ}C\;to\;150^{\circ}C$ within 1.5 seconds with the temperature variation of ${\pm}5^{\circ}C$ in 4-inch diameter area, using the induction heating apparatus.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.1
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• pp.38-42
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• 2017

This study proposes an idea for energy saving in apartment machine rooms. A conventional district heating system is equipped with constant-flow pumps and bypass valves to regulate pump differential pressure. Each family unit is equipped with a constant-flow on/off valve. This leads to excessive hot water circulation and a high return temperature. To reduce energy loss, this study assumes that each family unit is renovated with a heating valve which regulates the return temperature at $35^{\circ}C$. The hot water supply pump is also replaced with a pump with an inverter to vary flow rate. Expected energy savings is then estimated from field test data. According to the results, pump electricity consumption was reduced by 6,100 kWh for a family unit building over about half a year. The supply temperature can also be lowered by $5^{\circ}C$, which can contribute to a production of electricity of 10.3 kWh/ton of hot water.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.3-8
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• 2006

The heat pump system is attractive alternatives to conventional heating and cooling systems owing to their higher energy utilization efficiency. The thermal loads of commercial and institutional buildings are generally cooling-dominated. In this study have been developed ice storage type heat pump system for cooling and heating by heat pipe. This system was practiced performance test on evaluation criteria for heat storage systems. Accomplished the actual proof examination and looked into the performance of the system. In this study, measurement and analysis of ice storage type heat pump system for cooling and heating by heat pipe. The heat pump unit COP appears 3.05 for cooling and 4.20 for heating. As a result, the method to energy saving and to using a substitute energy actively that is heat pump cooling & heating system is expected by heat pipe. Thermal storage capacity appears $19.5RTH/m^3$ for cooling.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.1
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• pp.80-91
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• 2014

The aim of this study was to establish the superiority of ohmic heating over conventional heating for the sterilization of mulberry juice. Heat treatment of fresh juice significantly reduced the concentration of soluble solids, lowered the pH, and lowered the reducing sugar content (p<0.01). Color measurements showed decreases in the L and a values and increases in the b, H and C values after heat treatment, although the total color differences were smaller after ohmic heating than after conventional heating of fresh juice. The antioxidant capacities, such as reducing power, FRAP, and DPPH, decreased in the order of fresh juice, ohmically heated juice and conventionally heated juice. Furthermore, the anthocyanin, flovonoid, and total antioxidant capacities of the juices significantly decreased in the same order. Sensory evaluations showed no difference between fresh and ohmically heated mulberry fruit juice excluding off-flavor, whereas conventionally heated juice received significantly lower evaluations. The microbial counts were zero in the juice after either heat treatment. Thus, ohmic heat treatment can be effectively used to sterilize fresh mulberry juice to obtain good shelf life with minimal physicochemical, color, antioxidant and sensory deterioration.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.1033-1036
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• 2002

Wafer bonding methods such as fusion and anodic bonding suffer from high temperature treatment, long processing time, and possible damage to the micro-scale sensor or actuators. In the localized bonding process, beating was conducted locally while the whole wafer is maintained at a relatively low temperature. But previous research of localized heating has some problems, such as non-uniform soldering due to non-uniform heating and micro crack formation on the glass capsule by thermal stress effect. To address this non-uniformity problem, a new heater configuration is being proposed. By keeping several points on the heater strip at calculated and constant potential, more uniform heating, hence more reliable wafer bonding could be achieved. The proposed scheme has been successfully demonstrated, and the result shows that it will be very useful in hermetic packaging. Less than 0.2 ㎫ contact Pressure were used for bonding with 150 ㎃ current input for 50${\mu}{\textrm}{m}$ width, 2${\mu}{\textrm}{m}$ height and 8mm $\times$ 8mm, 5mm$\times$5mm, 3mm $\times$ 3mm sized phosphorus-doped poly-silicon micro heater. The temperature can be raised at the bonding region to 80$0^{\circ}C$, and it was enough to achieve a strong and reliable bonding in 3minutes. The IR camera test results show improved uniformity in heat distribution compared with conventional micro heaters. For gross leak check, IPA (Isopropanol Alcohol) was used. Since IPA has better wetability than water, it can easily penetrate small openings, and is more suitable for gross leak check. The pass ratio of bonded dies was 70%, for conventional localized heating, and 85% for newly developed FP scheme. The bonding strength was more than 30㎫ for FP scheme packaging, which shows that FP scheme can be a good candidate for micro scale hermetic packaging.

• Journal of the Korean Solar Energy Society
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• v.26 no.4
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• pp.127-134
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• 2006

In this paper, an experiment was carried out to investigate the thermal behavior and performance on a solar space heating & hot water system in an apartment. Measurement was continued for 6 months between January 1st 2004 and June 31th 2004. The results show that there is no problem in control and operation in case of connection this system with conventional space heating and hot water system, and that the thermal performance of this system and indoor thermal environment is good.