• Journal of Energy Engineering
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• v.5 no.1
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• pp.50-55
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• 1996

A numerical simulation on a primary calcinator of porcelain was performed with using Fluent to calculate the heat efficiency by studying velocity vector and temperature profile according to variables such as the location of outlet and porcelain. Control-Volume based Finite Difference Method and Up-wind scheme are used for discretization of differential equation. SIMPLEC Algorithm and standard k-$\varepsilon$ turbulent model are selected to resolve the pressure-velocity coupling and the turbulent. The result of simulation showed that the whole velocity vector field in a calcinator was varied greatly according to the location of outlet. But the whole temperature profile at each zone was still high regardless of the location of outlet because of the radiation. But the temperature of a case with a outlet at sidepart of preheating or cooling zone was little high compared to the case with a outlet on the top of preheating zone. The velocity vector field and temperature profile in a calcinator were almost not affected by the location of porcelain, but the temperature inside a porcelain was much affected according to the place where it was located. The heat efficiency in a calcinator was 44.6% and the gas temperature in the outlet was about 1000 K.

• Archives of Plastic Surgery
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• v.33 no.4
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• pp.474-479
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• 2006

Purpose: To report of a series of successful reconstruction of soft tissue defect on distal leg with extensor digitorum brevis myo-cutaneous flap. Methods: Between April 2002 to December 2004, 7 patients with soft tissue defect on distal leg were operated with Extensor Digiotorum Brevis myocutaneous flap. 6 of these patients had osteomyelitis. Results: Extensor Digiotorum Brevis myocutaneous flap were used in 6 patients and reverse flow flap was used in one patient. Average follow up was 19 months. All flap were survived 100% without any complication and osteomyelitis were controled in all cases. Aesthetic and functional out come were excellent on both recipient and donor sites. Conclusion: The advantages of this flap are effectively control of local wound infection, constant and reliable anatomical structures, adequately thin flap. Technical easiness for raising flap and wide arch of rotation. Extensor Digitorum Brevis myo-cutaneous flap is one of ideal option for the reconstruction of distal leg and foot defects.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.5
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• pp.732-737
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• 2012

The aim of this study is examine the protection effect for artery and antithrombotic effect of Sokmyong-tang(SMT; xuming-tang) on carotid artery thrombosis in a rat model. Thirty minutes before $FeCl_3$ treatment, SD rats were intraperitoneal injected with SMT. We tested the effects of SMT on time to occlusion (TTO) in thrombosis model by induced $FeCl_3$ using the laser Doppler flow meter and accessed thrombus weight (TW) inhibition and measured collagen fibers in the vessel after injury using Masson's trichrome stain. SMT(100 mg/kg, i.p.) showed significantly delayed TTO ($13.17{\pm}1.33$ min, P < 0.001) compared to vehicle control group ($8.63{\pm}0.92$ min) and inhibiting effect on TW with $0.72{\pm}0.02$ mg/mm (P < 0.05). In addition, SMT prevented collagen fibres damage in injured vessel ($22.24{\pm}4.48%$, P < 0.001). These results provide experimental evidence for SMT can be used to prevent vascular injury and thrombosis such as hypertension, arteriosclerosis, and so on.

• Journal of the Korean Society of Physical Medicine
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• v.11 no.4
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• pp.55-64
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• 2016

PURPOSE: The aim of this study was to examine the effect of air stacking exercise on lung capacity, activities of daily living, and walking ability in elderly adults. METHODS: A total of 27 subjects were randomly assigned to an experimental group (EG=13) or a control group (CG=14). Subjects in the experimental group participated in an active pulmonary rehabilitation program. 5 days a week for 4 weeks. The active pulmonary rehabilitation program was composed of an air stacking exercise with an oral nasal mask and manually assisted coughing. Conventional pulmonary rehabilitation exercises, such as, cough exercise, deep breathing, and abdominal muscle strengthening exercises were performed by both groups. Pulmonary function parameters, peak cough flow (PCF), and oxygen saturation were measured and the 6-minute walk test and Korean version of the modified Barthel index (K-MBI) scores were applied. RESULTS: Significant intergroup differences were observed for forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) results after intervention (p<.05), and for 6 minute walk test and PCF results after intervention and at 2-week follow-up visits (p<.05). Post hoc test results showed significant differences in K-MBI, 6-minute walk test, and FEV1 in the experimental group after intervention (p<.05). FVC values were significantly higher after intervention and at 2-week follow-up visits versus pre-intervention (p<.05). PCF values were also significantly higher after intervention and remained significantly higher at 2-week follow-up visits (p<.05). CONCLUSION: Air stacking exercise in elderly adults improves lung capacity and exercise tolerance.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2006.06a
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• pp.55-60
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• 2006

Draw-bead is applied to control the material flow in a stamping process and improve the product quality by controlling the draw-bead restraining force (DBRF). Actual die design depends mostly on the trial-and-error method without calculating the optimum DBRF. Die design with the predicted value of DBRF can be utilized at the tryout stage effectively reducing the cost of the product development. For the prediction of DBRF, a simulation-based prediction model of the circular draw-bead is developed using the Box-Behnken design with selected shape parameters such as the bead height, the shoulder radius and the sheet thickness. The value of DBRF obtained from each design case by analysis is approximated by a second order regression equation. This equation can be utilized to the calculation of the restraining force and the determination of the draw-bead shape as a prediction model. For the evaluation of the prediction model, the optimum design of DBRF in sheet metal forming is carried out using response surface methodology. The suitable type of the draw-bead is suggested based on the optimum values of DBRF. The prediction model of the circular draw-bead proposes the design method of the draw-bead shape. The present procedure provides a guideline in the tool design stage for sheet metal forming to reduce the cost of the product development.

• Proceedings of the KWS Conference
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• 2010.05a
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• pp.22-22
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• 2010

Eutectic composition phase with low melting point which solidifies at the final stage affects the solidification cracking at the intercellular or interdendritic area of welds and castings. If sufficient amount of eutectic composition liquid does not exist between the solidifying phases, the discontinuities remain as cracks. However, abundant amount of liquid eutectic composition existing in the final stage can flow into the discontinuities easily and heal the cracks. By flowing of liquid eutectic and healing of discontinuities, the possibility of cracking can be reduced when the amount of eutectic liquid is sufficient. For the solidification of pure metals, liquid eutectic does not exist and the interlocking of growing solid phases can be realized without interruption of liquid film. Therefore there is little possibility of solidification cracking in the case of welds and castings of pure metal. In a practical sense, the effective way to reduce or prevent the solidification cracking is making the composition of molten pool or melts near to the eutectic composition.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.3
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• pp.320-330
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• 2004

Most of domestic city is served combined sewer system among various sewer system like as separate sanitary, combined sewer system and storm sewers. During the wet weather, sewer and rainfall have been overflowed because it is over capacity of the combined sewer system; that is called combined sewer overflows(CSOs) This research was carried out to investigate runoff characteristics of combined sewer and to evaluate the effective CSOs volume in Hong-Chun gun. During wet weather, SS load of first rainfall at H-1, H-2, and H-3 were 600kg/event, 370kg/event, and 289kg/event, respectively. 55 load of second rainfall were 216kg/event, 113kg/event, and 37.2kg/event. When the first rainfall, event mean concentrations(EMCs) at each site were 702mg/L, 816mgjL and 861.5mg/L. The second rainfall's event mean concentrations(EMCs) were 99.9gm/L, 161.9mg/L, 103.6mg/L. Rrst flush coefficient b at each site were 0.237,0.166, and 0.151. When the first rainfall, the flow containing 80% of pollutant mass of CSOs at each site were 0.55, 0.23, 0.48 in first rainfall, respectively. The case of second rainfall were 0.79, 0.83, 0.81. Most of all, characteristics of rainfall like as analysis of first-flush, CSOs volume, pollutant loadings is investigated to decide intercepted volume for control of CSOs.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06a
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• pp.117-121
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• 2006

Virgin bleached kraft pulp, CPO (computer printout) and white ledgers are main raw materials used in tissue mills. The utilization rate of recycled fibers and virgin pulp in South Korea tissue industry are 90% and 10%, respectively. To improve brightness of printing grades the use of 'fluorescent whitening agents (FWAs)' or 'optical brightening agents (OBAs)' has been increased. When recycling these papers for tissue production, it is unavoidable that FWAs contained in recycled papers flow into tissue production lines and remain in the products. And this draws great attention from the public. This study was carried out to develop a technology for the removal of fluorescent whitening agents from recycled fibers. Enzymatic removal of FWAs was evaluated as a method to remove FWAs from the recycled fiber. The ${\alpha}-amylase$ that degrades starched used for surface sizing of fine papers and contained substantial condition is needed to prevent the re-adsorption of FWAs on fibers. The temperature of pulp suspension was another important factor affecting on FWA removal. The higher the temperature, the greater the efficiency of removing FWAs was obtained. Optimum pH and temperature for the effective removal of FWAs were suggested to be pH 8.5 and $65^{\circ}C$, respectively. The enzymatic removal of FWAs showed a great synergistic effect when proper control in pH and temperature was made.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.4
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• pp.68-75
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• 2007

In order to supplement insufficient nutrients of paper sludges, additional materials such as saw dust and rice husk were added during preparation of bed soils. Rice husk was more finely ground, compared to saw dust. The fine particles of the rice husk prevented their flow in a barrel of the expander. The mixed additives with paper sludges could be used to control the quantity of required nutrients for raising plants. That is, except for potassium and manganese, most of nutrients were decreased with adding the additives to paper sludge. The acidity of the paper sludges mixed with the saw dust or the rice husk was a little decreased with the increased amount of the additives. Differently from the bulk density of the paper sludges, the moisture content and the water absorption rate of the paper sludges were incremented with increasing the additives.

• Journal of the Korean Ceramic Society
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• v.45 no.12
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• pp.802-806
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• 2008

A proper sealant for low temperature SOFCs should show zero or low leak rates to avoid direct mixing of the fuel and oxidant gases or leakage of fuel gas during the operation of SOFCs. Furthermore, it should be chemically and/or mechanically stable in both oxidizing and reducing environments and chemically compatible with other fuel cell components. In the present work, we developed a novel compressed seal gasket of glass-based composite reinforced with ceramic particulate particles, which can efficiently control the viscous flow of glass matrix as well as the crystallization of glass phase. This novel sealing gasket showed excellent gas tightness under very low compressive load which would be suitable for the operation of SOFCs in the temperature range $600{\sim}650^{\circ}C$.