• Korean journal of food and cookery science
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• v.15 no.4
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• pp.353-357
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• 1999

The textural characteristics of mungbean flour gels and mungbean cake(Bindaedduk) were investigated in steam and microwave reheating condition after 20$^{\circ}C$, 5$^{\circ}C$ and -18$^{\circ}C$ storage. The hardness of mungbean flour gels were 2.36 kg in microwave reheating and 3.59 kg in steam reheating after 6 days frozen storage, respectively and its gumminess were increased after reheating. The hardness of mungbean flour gels did not significantly change with the storage temperature. The textural characteristics of mungbean cake made with 2 parts of mungbean flour and 1/2∼1/8 parts of nonwaxy rice flour had the similar values in spite of the different compositions. Microwave reheated mungbean flour gels had the different hardness values of 4.13 kg in non package and 1.70 kg in polyethylene film wrap after 24 hours storage at 20$^{\circ}C$. In sensory evaluation mungbean flour gels showed the high scores in hardness and the unpleasant flavor after reheating but mungbean cake of different compositions showed the good sensory qualities.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.3
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• pp.284-291
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• 1999

Recently the ductile cast iron is being used successfully to the parts for processing machinery vessels and gear etc. This study is mainly concerned with the heat treatment for the specimens of crank shaft which are made of ductile cast iron. The results obtained are summarized as follows. Comparing the mechanical properties of the specimens for the normalized ductile cast irons the specimen heat treated at $550^{\circ}C$ was the best for crank shaft of air-compressor. After austenizing at $910^{\circ}C$ it was observed that the higher the reheating temperature is the less tensile strength and the hardness became which was supposedly attributed to the fact that the amount of pearlite. Austenite matrix was reduced by reheating after normalizing and that as the reheating tem-perature went up the pearlite generated was less and the distance between the pearlites were widened at last made pearlite globular. In the comparsison of crank shaft for air compressor made of ductile cast iron with that made by forged steel the crank shaft made of ductile cast iron was superior in economical terms. And ductile cast iron could be practically enough if only the elonga-tion which was inferior mechanical property to forged steel could be reinforced by increasing the diameter of crank pin when designing the crank shaft.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.10 s.253
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• pp.950-956
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• 2006

A mathematical heat transfer model for the prediction of heat flux on the slab surface and temperature distribution in the slab has been developed by considering the thermal radiation in the furnace and transient conduction governing equations in the slab, respectively. The furnace is modeled as radiating medium with spatially varying temperature and constant absorption coefficient. The slab is moved with constant speed through non-firing, charging, preheating, heating, and soaking zones in the furnace. Radiative heat flux which is calculated from the radiative heat exchange within the furnace modeled using the FVM by considering the effect of furnace wall, slab, and combustion gases is applied as the boundary condition of the transient conduction equation of the slab. Heat transfer characteristics and temperature behavior of the slab is investigated by changing such parameters as absorption coefficient and emissivity of the slab. Comparison with the experimental work shows that the present heat transfer model works well for the prediction of thermal behavior of the slab in the reheating furnace.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.4
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• pp.440-446
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• 1999

This study is mainly concerned with the friction and wear properties for the specimens of crank shaft which are made of ductile cast iron. The friction and wear tests were carried out for the nor-malized ductile cast iron specimens and their properties were compared with each other at reheat-ing temperatures(550^{\circC,\; 600^{\circ}C,\; 650^{\circ}$) and in dry condition at different friction velocity(0.94 m/s 1.88m/s 2.83m/s) range. After austenized at $910^{\circ}C$ it is observed that the higher the reheating temperature is the hardness becomes decrease which is supposedly attributed to the fact that the amount of pearlite austenite matrix is rduced by reheating after normalizing and that as the reheating temperature goes up the pearlite generated is less and the interval between the pearlites were widened at last to make pearlite globular. At the low velocity the friction coefficient increase in the beginning and gets stabilized as the sliding distance increases. As the friction velocity grows the friction coefficient decreases suppos-edly since the abrasive wear is heavier at low velocity than at the high velocity as the friction tem-perature at low velocity is lower than at high velocity.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.10a
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• pp.60-63
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• 2003

Semi-solid forming is the process of stirring alloy during solidification, making the mixture of liquid and solid, solidifying it, reheating it to the solid-liquid coexistent temperature, and then injecting this semi solid slurry into dies. In the semi-solid die casting process, it is very important to find out the correlation of injection condition, microstructure and mechanical properties. Especially, an improper injection condition is the main cause of liquid segregation and non-homogeneous mechanical properties due to the difference of solid fraction according to the position of the products. To ensure the database requisite to the semi-solid die casting product, it is essential to acquire the mechanical properties considering liquid segregation to the injection condition. In this study, the effect of injection condition on liquid segregation, formability, microstructure and mechanical properties in a thin product was investigated.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.911-916
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• 2004

Widely used vegetables such as onion, soybean sprout, and carrot in Korean dishes were studied to reduce losses in firmness during cook/chill storage for food service system. Blanching at 7$0^{\circ}C$ affect positively on textural properties of the three vegetables while reheating at the food service practice. Firmness of the vegetables was improved and stabilized with addition of calcium ion in blanching solution during storage at refrigeration temperature. Calcium was effective to improve or sustain firmness during blanching. The effect of calcium on firmness of blanched and cooked soybean sprout was less significant than that of carrot and onion, especially at short period of storage under refrigerated condition. In conclusion, low temperature blanching with calcium ion was effective to maintain firmness of the three vegetables before cooking while refrigerated storage of the cooked vegetables and subsequent reheating for food service system.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.322-327
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• 2007

Dedicated outdoor air-conditioning(DOA) system that utilizes pre-cooling and desiccant dehumidification can be superior to conventional cooling and reheating system with respect to energy consumption and indoor thermal comfort. In this work, simulation has been conducted to study various factors that affect the performance of DOA. Dynamic simulation shows the transient variation of temperature and humidity as the on/off control logic is imposed. Exit humidity of process air and flow rate are varied to study the effect on exit temperature of process air, dehumidification quantity, required regeneration temperature and exit humidity of regeneration air. For an outdoor air condition of $28.5^{\circ}C$ temperature, 16 g/kg humidity ratio and 2000 cmh flow rate, the dehumidification efficiency is increased by 4.6% as the flow rate is doubled.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.16 no.6
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• pp.613-619
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• 1987

In a room air conditioning cooling system, if the room-sensible-heat-factor as plotted on a Psychrometric Chart intersects the saturation curve below the apparatus leaving air dewpoint, reheat must be used to maintain the design room air conditions. However, if the design room humidity is permitted to be raised to some degree, the cooling system will not require reheat as a new room-sensible-heat-factor line is developed between the apparatus leaving air dew-Point and the adjusted design room air conddition point. The advantages to this are the cost of reheat equipment and operation can be avoided. The cycle of this system can be shown on a Psychrometric Chart to plot the design condition points.

• Nuclear Engineering and Technology
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• v.17 no.1
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• pp.8-15
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• 1985

A model for thermal interactions of debris/water with gas flow from within and below debris bed was presented for severe accident analysis in LWR. The consumption of steam, production of hydrogen in the debris bed, generation of gases from below debris bed and generation of chemical heat are included in the conservation equations. The model has been incorporated in the MARCH code to estimate the gas production due to both metal/oxidation and hot debris/concrete interaction. The results indicate that the hydrogen source can potentially give a significant impact on the containment pressure transient and the conductive heat loss to concrete and the convective gas cooling in the debris bed have a small effect on the debris bed coolability. However, the reheating and melting of the debris particles could be delayed by the interaction of debris with concrete.

• Journal of Energy Engineering
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• v.24 no.3
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• pp.82-88
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• 2015

After a reheating furnace installation, the modification of the size and the heat capacity is very difficult. Therefore, the development of design package tool is required for the computation on the correct specifications before the design and the installation. Prior to development of the design tool, a module that calculates the amount of heat loss of each part according to the specifications for determining the thermal efficiency of a continuous heating furnace was developed and applied to the oxy-fuel industrial furnace. Through this, the effects of fuel type, oxygen fraction and recirculation on the efficiency of the furnace of which the output is 110Ton/hour were analyzed. In oxy-fuel combustion condition, the efficiency was 15% higher than air combustion conditions. With the using COG(Coke Oven Gas) instead of LNG, the efficiency was slightly increased. In the air combustion condition, the efficiency was increased about 33% with the preheated air. But, in oxy-fuel condition, the amount of exhaust gas was reduced, so the efficiency was increased about 7%.