• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.298-299
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• 2005

Differently from the tensile, transverse compression and torsion cases, the bending test of HTS tapes requires a lot of time and efforts, since the sample should be mounted successively onto bent sample holders in the order of decreasing radius and measuring the $I_c$ at each step. The influence of repeated cooling and warming experienced during these processes on the $I_c$ degradation can not be ignored. As a result, in this study, particularly. a new one-body type sample holder which provides continuous bending strains at 77K was devised. And, $I_c$ degradation behavior of Bi-2223 tapes under easy bending condition was investigated and compared that with other cases using Goldacker-type bending tester or respective sample holder.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.57-61
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• 2003

Variations in NMR relaxation time during freezing and thawing processes in pork loins were investigated. Continuous distribution analysis of data obtained from $T_2\;CPMG$ were carried out to observe the changes in water content in the muscles. Solid fat content slightly increased with decreasing temperature, then showed sharp increase at $-4^{\circ}C$, reaching 85% at $-25^{\circ}C$. Relaxation time decreased with decreasing temperature, suggesting that ice crystals gradually formed at freezing temperature. $T_2$ relaxation time during thawing was higher than that during freezing, suggesting that ice crystals melted by thawing and resulted in water loss from meat. Continuous distribution analysis of data obtained from Carr-Purcell-Meiboom-Gill experiments shows one to four components on the spectra during freezing and thawing processes. The area of major components between 30 to 45 ms decreased with decreasing temperature, and were not detected below $-4^{\circ}C$, below which only $T_s$ signal was detected. The area of $T_s$ decreased with decreasing temperature. Between -4 to $10^{\circ}C$, the areas of $T_m$ and $T_l$ during thawing were larger than those during freezing. These results suggest that the exchange between bound water and free water takes place during freezing and thawing.

• Journal of Animal Environmental Science
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• v.4 no.2
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• pp.149-160
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• 1998

Hog manure slurry amended with sawdust was composted in pilot-scale reactor vessels using continuous aeration nuder different C/N ratios and pH conditions during composting high rate (decomposition) process. For each material two replicated piles were built and monitored over a period of three weeks. The compost piles had an initial volume of 0.18 ㎥. In this study we evaluated the temperature in compost O2 and CO2 evolution, aeration rate, NH3 concentration etc. and investigated the stability of compost during composting high rate process. According to measured results, while the maximum NH3 concentration during composting high rate process. According to measured results, while the maximum NH3 concentration during composting high rate was in the range of 213 to 412 ppm on 5th day which was near the optimum C/N(22∼24) and pH(7.5∼7.9). And then, the NH3 concentration reduced to between 22∼26 ppm by 13th day. The maximum NH3 concentration for the lower C/N(18∼19) and pH value of 6 reached 574∼1,063 ppm by the 16th through 11th days and the NH3 concentration during continuous aerated composting high rate process, it was more important to manage NH3 gas so that compost odor is reduced.

• Journal of Biomedical Engineering Research
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• v.31 no.1
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• pp.81-86
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• 2010

Laser irradiation is known to affect various tissues such as skin, bone, nerve, and skeletal muscle. Laser irradiation promotes ATP synthesis, facilitates wound healing, and stimulates cell proliferation and angiogenesis. In skeletal muscle, laser irradiation is related to the proliferation of skeletal muscle satellite cells. Normal skeletal muscle contains remodeling capacity from myogenic cells that are derived from mononuclear satellite cells. Their processes are activated by the expression of genes related with myogenesis such as muscle-specific transcription factors (MyoD and Myf5) and VEGF (vascular endothelial growth factor). In this study, we hypothesized that laser irradiation would enhance and regulate muscle cell proliferation and regeneration through modulation of the gene expressions related with the differentiation of skeletal muscle satellite cells. $C_2C_{12}$ myoblastic cells were exposed to continuous/non-continuous laser irradiation (660nm/808nm) for 10 minutes daily for either 1 day or 5 days. After laser irradiation, cell proliferation and gene expression (MyoD, Myf5, VEGF) were quantified. Continuous 660nm laser irradiation significantly increased cell proliferation and gene expression compared to control, continuous 808nm laser irradiation, and non-continuous 660nm laser irradiation groups. These results indicate that continuous 660nm laser irradiation can be applied to the treatment and regeneration of skeletal muscle tissue.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.573-577
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• 2013

Heat pumps come into wide use because high energy efficiency can be obtained and diverse heat sources like geothermal heat, waste heat and air are available. It is necessary for an air source heat pump to defrost in order to remove frost on the surfaces of an outdoor heat exchanger. It is impossible for continuous heating if reverse cycle operation is used as defrosting method, furthermore it causes the degradation of COP. In this study an fin-tube heat exchanger with three rows was used as an outdoor coil. One row among three rows of the heat exchanger was used like a condenser in order to remove frost on it, the others were used as evaporator to accomplish continuous heating. Each row was switched in order from a condenser to an evaporator in specified time interval. Tests were carried out during minimum 180 minutes at the defrost-heating test condition(dry bulb temperature $2^{\circ}C$, wet bulb temperature $1^{\circ}C$) described in KS C 9306. Time-averaged COP was about 20% higher than that of conventional defrosting method.

• KSBB Journal
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• v.8 no.2
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• pp.143-149
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• 1993

Activated carbons were used to examine their performance for the separation of undesirable colored materials from culture broth containing hyaluronic acid. Six local samples and a NORIT ROX 08 were tested, whereas the latter was mainly studied under batch and continuous modes. The optimal wavelength for the detection of colored materials was 330nm. The optimal choice of NORIT ROX 08 provided 30% colored residuals with 96% hyaluronic acid recovery of original broth in batch experiments. The nonlinear adsorption behavior of protein and colored materials with activated carbon (C) was correlated by a Langmuir equation to give 18C/24+C and 500C/892+C for protein and colored materials, respectively. It appears that colored materials were composed of 78% protein and 22% glucose residuals on the basis of clearance results. A microscopic study using a scanning electron microscope suggests that regeneration of used activated carbon with 0.1N NaOH and hot water was not satisfactory. The present study proposes that the continuous monitoring of colored materials during purification can be accomplished by Installation of a UV monitor commonly used for continuous detection of protein during the process, as resulted from the significant correlation of color (A330)=0.353protein(mg/ml)+0.1(R=99.7%).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05a
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• pp.42-45
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• 2003

The phase transformation of $REBa_2Cu_3O_{7-x}$ (RE=Nd, Gd, Dy) was investigated using isothermal heat-treatment and continuous cooling in air. During continuous cooling, the $REBa_2Cu_3O_{7-x}$ (RE=123) superconducting phase with well-distributed $REBa_2Cu_3O_{7-x}$ (RE-211) was obtainde at a cooling rate of $0.001^{\circ}C$/s. Single phase RE-123 (Nd, Gd, Dy) was stable at $1050^{\circ}C$, $1050^{\circ}C$, and $950^{\circ}C$ during isothermal heat-treatment, respectively. Above these temperatures the RE-211 phase existed within the RE-123 grains. The RE-123, RE-211, $BaCu_2Od_2$, and CuO phases coexisted at $50^{\circ}C$ below the partial melting temperature for each respective rare-earth RE-123.

• Korean Journal of Materials Research
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• v.13 no.3
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• pp.137-143
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• 2003

The air gap between the metal and mold, formed by shrinkage during solidification, causes surface and subsurface cracks in the continuous casting process. Molten crack on the surface might also occur due to improper heat transfer between them. In order to compensate the air gap in mold design, the thermal contraction is an essential factor. In this study, the thermal contraction and expansion behaviors were examined from the ($\alpha$ and pearlite)/${\gamma}$ to ${\gamma}$/$\delta$ transformations in continuous casting steels by the commercial dilatometer and the self- assembled dilatometer with laser distance measurement. It was found that the thermal contraction and expansion behaviors were very dependant on the phase transformation of the ${\gamma}$/$\delta$ as well as ($\alpha$ and pearlite)/${\gamma}$. The sudden volume change from $\delta$ to ${\gamma}$ which might cause cracks in the continuous casting process, was observed on cooling just below the melting temperature by the self-assembled dilatometer.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06c
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• pp.46-48
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• 2006

This paper addresses the problem of monitoring continuous k-nearest neighbor (k-NN) queries. Given a set of moving (or static) objects and a set of moving (or static) query points, monitoring continuous k-NN query retrieves and updates the closest k objects to a query point continually. In order to support location based services (LBSs) in highly dynamic environments, where objects and/or queries are frequently moving, monitoring continuous queries require real-time updated results when objects and/or queries change their locations. Thus, it is important to minimize time delay for maintaining up to date the results. In this paper, we present monitoring method to shorten time delay for updating continuous k-NN queries based on the notion of result region and the minimum bounding rectangle enclosing all objects in each cell, referred to as c-MBR, in the grid index structure. Simulations are conducted to show the efficiency of the proposed method.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.7
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• pp.596-602
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• 2006

Ice adhesion and blockage problems have been issued in continuous ice slurry making process. So we composed continuous ice slurry making device using a commercial small plate heat exchanger (PHX), and investigated character of ice formation. An experiment of ice formation was peformed with an aqueous solution of ethylene glycol 7 mass%. In the experiment, the effect of the pressurization on ice slurry formation during the cooling process was investigated. The pressurization test for the aqueous solution was performed by setting valves at the PHX inlet and outlet. At the results, the time of continuous ice formation increased as the pressure of the plate heat exchanger increased for cooling temperature of $-5^{\circ}C$. Also continuous ice formation at the cooling temperature of $-7^{\circ}C$ showed a possibility. It was found that the pressurization may contribute to suppress the dissolution of supercooled aqueous solution in the PHX.