• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.7
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• pp.549-556
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• 2001

Heat flow characteristics during hot water extraction process was studied experimentally. Data were taken at various outlet port type for the fixed inlet port type, inlet-outlet temperature differences and mass flow rates. In this study, the temperature distribution in a storage tank and an outlet temperature were measured to predict a flow pattern in the storage tank, and a hot water extraction efficiency was analysed with respect to the variables dominating a extraction process. Experimental results show that the extraction efficiency is high in a low flow rate in case of using modified distributor I(MDI) as a outlet port type.

• Journal of the East Asian Society of Dietary Life
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• v.11 no.1
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• pp.33-43
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• 2001

The effects of the addition of herbs belonging to Allium species on the quality and storage characteristics of kamaboko were studied. The herbs employed in the study were garlic (Allium sativum for.Pekinenese Makino), leek(.Allium tuberosum Roth), onion(Allium cepa Linnaeus), and onion skin. water activity(Aw) , pH, TBA, VBN, microbial load, textural characteristics and sensory evaluation were tested. 1. Aw of all the samples decreased on storage, the Aw on lower day ranged from 0.937~o.950. All thesamples containing herbs retained the pH 6 ~7 during the entire storage period even though it decreased gradually on storage. 2. In general, TBA and VBN of the samples containing herbs were lower than the control. The sample containing 3% onion skin showed the lowest TBA and VBN value. 3. The total plate count of the samples containing herbs was low compared to the control even though the total count increased during the storage. The samples containing 3% garlic and 3% onion skin showed the lowest total plate count on 20 days of storage. 4. The sample with garlic showed remarkably low value in sensory evaluation. The samples containing onion and onion skin, however, reached to the high sensory points as storage period increased. They received high points in taste as well as overall acceptance.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.6
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• pp.677-683
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• 2006

Glutinous rice cake(Chalduk) was made by varying the hours of soaking time of glutinous rice in the water(0, 4, 8, 12, 24 hours). After storage for various periods, the sensory and physical characteristics and the degree of gelatinization were examined in order to determine the effect of glutinous rice soaking period on the quality of Chalduk. The results of the study are summarized as follows. In the sensory test, 8-hour water soaking produced the significantly highest score for salty taste, while 0-hour water soaking had the lowest score. Four-hour water soaking had the significantly highest score for the degree of chewiness. Eight-hour water soaking had the significantly highest score for overall desirability. For the moisture content of Chalduk covered with bean flour, 8-hour water soaking produced the highest moisture content but the difference was not significant. For the degree of gelatinization, 8-hour water soaking had the highest maltose content, which confirmed the suitability of 8-hour water soaking glutinous rice. Eight-hour water soaking had the lowest hardness. With increasing storage period, the hardness sharply increased. Elasticity was higher for the long-period immersed samples than for the non-immersed samples. In conclusion, an 8-hour soaking time for glutinous rice in water was proposed to maximize the Chalduk quality.

• Solar Energy
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• v.20 no.3
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• pp.1-9
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• 2000

In these days the hot water circulating Ondol using the fossil fuel boiler is the heating system for the most of the Korean residents. Then it is installed without the heat storage medium in the Ondol heating layer, but the Korean traditional Ondol had been composed with the heat storage medium. The Ondol room without heat storage medium could not be comfortable because the room air temperature is not only changed unstably but also it has a defect too much fuel consumption. Therefore in this study the heat pump-latent heat storage Ondol as the new type of Ondol system was developed to solve these problems mentioned above, and the COP of the heat pump (Coefficient Of Performance), the latent heat storage characteristics in the new type of Ondol system and the temperature variation in the Ondol room with the ambient temperature were analyzed.

• International Journal of Air-Conditioning and Refrigeration
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• v.10 no.1
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• pp.31-39
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• 2002

Microencapsulated pcm (MPCM) particles are mixed with distilled water and utilized to evaluate its characteristics and performance as a thermal storage medium transporting heat. For the present study, tetradecane ($C_14$$H_30$, $T_m$=5.5$^{\circ}C$) is capsulated in the core, coated with the melamine for their surface. The size of particles is well-controlled under 10$\mu$m in the process of in-situ polymerization with melamine-formaldehyde resin. For the experiment, the concentractions of slurries are prepared for 20 wt%, 30 wt%, and 40 wt%. The results are compared with those of water and 100% tetradecane oil. The pure water and tetradecane start solidifying within 20 minutes after introducing cooling water into the thermal storage tank whose flow rates are varied by 125 cc/min, 250 cc/min, and 500 cc/min. However, MPCM slurries are required relatively longer period of time for their phase change than pure phase change materials. That is, the entrained MPCM particles restrict their heat transfer in terms of natural convection and conduction to them.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.6
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• pp.830-837
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• 2011

This study was carried out to investigate the quality characteristics of yellow layer cake mulberry powder. After making yellow layer cake with mulberry powder, water activity, crumb texture, crumb color, and sensory tests were investigated. After 1 day of storage, Aw of control with weak flour did not show any significant difference, whereas those with 1, 3. 5% mulberry powder showed a significant decrease in Aw. During storage, the Aw values of yellow layer cakes containing mulberry powder were consistent. Hardness, springiness, cohesiveness, and gumminess of the yellow layer cakes containing mulberry powder all decreased compared to those of control. Hardness, springiness, cohesiveness, and gumminess all increased with storage time. Further a higher percentage of mulberry powder was associated with a lower L value, but higher a value. b values were lower in the 1% and 3% mulberry powders, but 5% showed a slightly higher b value. An increase in storage time was associated with decreased L and b values and increased a value. The micrographs of yellow layer cakes with mulberry powder showed a slightly coarser porosity than that of controls. The results of the sensory test showed that the over-all acceptability of 1% mulberry powder cake was the best.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.697-700
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• 2005

Aquifer Thermal Energy Storage (ATES) system can be very cost-effective and renewable energy sources, depending on site-specific parameters and load characteristics. In order to develop an ATES system which has certain hydrogeological characteristics, understanding of the thermo hydraulic processes of an aquifer is necessary for a proper design of an aquifer heat storage system under given conditions. The thermo hydraulic transfer for heat storage is simulated using FEFLOW according to two sets of pumping and waste water reinjection scenarios of heat pump operation in a two layered confined aquifer. In the first set of model, the movement of the thermal front and groundwater level are simulated by changing the locations of injection and pumping well in seasonal cycle. However, in the second set of model the simulation is performed in the state of fixing the locations of pumping and injection well. After 365 days simulation period, the temperature distribution is dominated by injected water temperature and the distance from injection well. The small temperature change is appears on the surface compared to other slices of depth because the first layer has very low porosity and the transfer of thermal energy are sensitive at the porosity of each layer. The groundwater levels and temperature changes in injection and pumping wells are monitored to validate the effectiveness of the used heat pump operation method and the thermal interference between wells is analyzed.

• Korean journal of food and cookery science
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• v.19 no.6
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• pp.753-757
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• 2003

The quality characteristics of the traditional Korean snack Yut-gang-jung with Perilla, and the changes that occur during storage were investigated. The water and protein content of a fresh sample were 9.67％ and 10.83％, respectively. The water content in the sample stored at 20$^{\circ}C$ changed slightly, but that of the sample stored at 60$^{\circ}C$ showed larger changes from 9.33 ％ to 4.33％. The acidity of the sample stored for 8 days was significantly higher. The hardness of the sample stored at 60$^{\circ}C$ for 4 days was increased significantly. Results of the sensory evaluation indicated the sample stored at 60$^{\circ}C$ had a significantly decreased roasted perilla flavor. The rancid flavor of the sample stored at 20$^{\circ}C$ increased slightly, while that of the sample stored at 60$^{\circ}C$ showed a drastic increase during storage. Therefore, a one week storage of the Yut-gang-jung with Perilla at room temperature is recommended for a product to have a shelf-life with similar physicochemical and sensory properties to fresh samples.

• Korean journal of food and cookery science
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• v.26 no.6
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• pp.821-830
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• 2010

This study was carried out to investigate the quality characteristics and storage of wet noodle with added Cheonnyuncho powder. Wet noodles were prepared at concentration of 1, 3, and 5%(w/w) of the fruit based on flour weight. Moisture content of the noodles with or without Cheonnyuncho powder was 34~36%. Ca, K, Mg, Fe, Mn and Zn contents of Cheonnyuncho noodle were increased at increasing concentrations of Cheonnyuncho powder. Cooked weight, volume, and water absorption decreased with increased fruit powder, whereas turbidity increased. For hunter's color values of noodles, L(lightness) and b(yellowness) values decreased with increasing concentration of Cheonnyuncho powder, whereas a(redness) value increased. For mechanical characteristics of the noodles, adhesiveness, cohesiveness, chewiness, elasticity, and brittleness of cooked noodle with Cheonnyuncho powder were lower than those of control. The pH of Cheonnyuncho noodle was lower than that of control during storage. Bacterial counts of wet noodle with 1% and 3% fruit powders were lower than those of the control and 5% fruit powder on the 8th day of storage at $5^{\circ}C$. From the sensory evaluation, texture, taste, and overall preference were not significantly different between the control and fruit group, but the color of 5% Cheonnyuncho noodle was significantly higher than that of control (p<0.05). In conclusion, the results of this study suggest that the addition of 1% and 3% Cheonnyuncho powder in combination with flour tended to improve antimicrobial effects during storage when compared to control.

• Food Science and Preservation
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• v.18 no.3
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• pp.279-287
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• 2011

The purpose of this research is to develop bellflower (Platycodon grandiforum) root Jeonggwa as a health food. The Omija (Schizandra chinensis Baillon) water extract with 0-8% (w/w) Jeonggwa added was stored at $25^{\circ}C$ for 12 weeks. The quality characteristics of Jeonggwa during storage were investigated. The Jeonggwa showed a lower pH and a higher acdity as the amount of Omija water extract that was added increased. The moisture content of Jeonggwa were rose from 15-18% to 16-22% within 2 weeks of storage, and remained at that level up to the end of storage. The total viable cells of bellflower root Jeonggwa were 2.1~2.3 log CFU/g and increased in number during storage but never exceeded 4 log CFU/g. The shelf life of the Jeonggwa was extended when the Omija extract was added. The lightness (L), redness (a) and yellowness (b) of the Jeonggwa during its storage at $25^{\circ}C$ were highest in control samples, and the values decreased with the increase in the Omija extract concentration (p<0.001). The mechanical evaluation of the Jeonggwa showed that various tested parameters fell during the storage at $25^{\circ}C$. The hardness and strength of the Jeonggwa significantly decreased as the Omija extract concentration rose (p<0.05). In the ensory evaluation tests, the acceptability of the Jeonggwa was optimal when 4~6% of Omija extract was added to it.