• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.9
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• pp.563-570
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• 2017

Experimental and numerical studies were performed to investigate the performance and internal flow characteristics of a supersonic second throat exhaust diffuser (STED) with back pressure ($P_a$). An ejector system was used to vary the back pressure ($P_a$) conditions. The operating gas for the STED and the ejector was high pressure nitrogen at room temperature. When the back pressure ($P_a$) at a constant nozzle inlet pressure $P_0$) decreases, the pressure recovery location moves downstream. If the pressure ratio $P_0/P_a$) is the same, even if the nozzle inlet pressures $P_0$) are different, the diffuser's internal flow pattern and starting pressure ratio ($(P_0/P_a)_{st}$) are almost the same.

• Clinical and Experimental Pediatrics
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• v.63 no.5
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• pp.189-194
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• 2020

Background: The decision to use transannular patching (TAP) during tetralogy of Fallot (TOF) repair depends on the pulmonary valve annulus size; the z score of the pulmonary annulus is the most commonly used predictor. However, definitive results are not obtained with z scores as different z score data sets are used for different parameters. Purpose: This study aimed to identify the echocardiographic and other key factors that warranted a change in the surgical method during TOF surgery. Methods: Sixty-two patients were enrolled and divided into a pulmonary valve (PV) preservation group and a TAP group. Their medical records were reviewed. Results: The z score for PV annulus (PVA), ratio of the PVA to aortic annulus size, and ratio of PVA to descending aorta (DAO) size were significantly different between the PV preservation and TAP groups (-1.72±1.52 vs. -3.07±1.94, P=0.004; 0.62±0.12 vs. 0.50±0.14, P=0.002; and 1.32±0.32 vs. 1.07±0.36, P=0.008, respectively). For TAP repair, the PVA z score had a sensitivity of 65.4% and specificity of 73.1%, ratio of PVA to aortic annulus size had a sensitivity of 73.1% and specificity of 65.4%, and ratio of PVA to DAO size had a sensitivity of 69.2% and specificity of 57.7%. The TAP group showed more monocuspid PVs (P=0.011), while the PV preservation group showed more tricuspid PVs (P=0.027). Commissurotomy was more frequently performed in the PV preservation group than in the TAP group (P=0.001). Of patients with commissurotomy, 58% showed a PV z score<-2. Conclusion: Although various echocardiographic parameters may serve as predictors for determining surgical methods for TOF patients, the PV morphology and tissue characteristics should also be considered.

• Journal of Food Hygiene and Safety
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• v.37 no.6
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• pp.411-417
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• 2022

The purpose of this study was to evaluate protein hydrolysis and the amino acid ratio among different cuts of goat meat, such as the foreleg, hindleg, loin, and rib, using an in vitro digestion model. The corresponding cuts of beef and pork were used to compare with the goat meat. The hindleg (8.32%) and rib (8.32%) had the highest levels of protein hydrolysis among the goat cuts. There was no significant difference in protein hydrolysis between goat and pork (8.57%), ribs (P > 0.05), which had higher levels of protein hydrolysis than the beef ribs. Before digestion, the glutamine (53.44%) and glycine (11.03%) ratios were highest in the pre-digested goat foreleg and loin (P < 0.05). After in vitro digestion, goat ribs had the highest lysine ratio (17.54%) among the different cuts, and the lysine ratio was significantly higher in goat ribs than beef ribs (P < 0.05). This study provides basic data on protein hydrolysis and the amino acid composition of different cuts of goat meat, which may facilitate the evaluation of protein digestion patterns and bioavailability.

• Journal of Korea Foundry Society
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• v.30 no.4
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• pp.130-136
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• 2010

Sulfide segregation behavior, characteristics of solidification microstructure and compositional distribution in the riser/castings junction of heavy-section main bearing support (MBS) steel castings were investigated; Sulfide streaks of A segregation were formed in the transitional region from columnar grain to coarse equiaxed grain and floated with aggregation of the dendritic free crystal. Solute segregation behaviors of elements Si, P and S were V shape negative segregation from the bottom of the castings to upper part of the riser with the reference of vertical center-line of the specimen block. Those of elements C and Mn were V shape negative segregation in the main body and A shape positive segregation in the riser of the casting. Just beneath the pipe shrinkage in the riser segregation ratio of each element was the highest, and that of S was 3.6 times higher, C 3.3 times, P 2.1 times, Si 1.6 times and Mn 1.0 times respectively. [Mn/S] ratio of the specimen block was distributed in the wide range of 20~275.

• Journal of Korean Physical Therapy Science
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• v.10 no.1
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• pp.74-82
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• 2003

The purpose of this study is to provide guideline of muscle strengthening exercise for preparing ambulation by presenting suitable ratio of muscle power of agonist & antagonist, and that of concentric & eccentric contraction on behalf of amputee's normal ambulation training and it's strenthening as well. 7 Subjects who have femur amputee for experimental group were able to ambulate naturally without inconvenience and 20 adult subjects of comparison group for comparison were considered to be free from disturbance of ambulation. The method of study was to measure the muscle power of hip pint, was to figure out the ratio of agonist & antagonist, concentric contraction & eccentric contraction, and was to find out mean and standard deviation of each measurement. Every numerical value of comparison was tested by Mann-whitney and comparison group's comparison between left & right value was done with t-test. Results are as followings : 1) Extension force was stronger than flexor force and had no remarkable difference(p<0.05) 2) For normal adults, adduction farce was stronger than abduction force and for amputees, abduction force was stronger while adduction force was the same as the normal without showing remarkable difference(p<0.05) According the result above, I make an assumption that maintaining a proper ratio of muscle power on strengthening exercise for amputee's ambulation training & rehabilitation and finally bring out an improvement of transfer and ambulation.

• Physical Therapy Rehabilitation Science
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• v.11 no.2
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• pp.198-206
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• 2022

Objective: This study was to investigate the effect of a lumbar stabilization exercise program accompanied by proprioceptive stimulation in women in their 20s with low back pain. Design: A randomized controlled trial Methods: A total of 30 women in their 20s with low back pain were selected and randomly assigned to an experimental group and a control group. Both groups performed a lumbar stabilization exercise program, and only the experimental group applied for a stabilization exercise program with proprioceptive stimulation. The exercise program lasted 60 minutes at a time, 3 times a week, for 4 weeks. The measurement tools used were the Numeric Rating Scale (NRS), the Korean version of the Oswestry Disability Index (K-ODI), the lumbar alignment, and the transverse abdominis(TrA) muscle thickness and contraction ratio. Results: Both groups showed statistically significant differences in NRS, K-ODI, and muscle thickness before and after the experiment (p<0.05). The lumbar alignment and contraction ratio at the time of contraction of TrA in the experimental group was statistically significantly increased, and there was also a significant difference in the difference between the two groups (p<0.05). Conclusions: The lumbar stabilization exercise program with proprioceptive stimulation reduced pain, improved low back pain induced dysfunction, and increased TrA muscle thickness and contraction ratio. Therefore, it can be an effective therapeutic exercise program for women in their 20s with LBP.

• Proceedings of the Korean Geotechical Society Conference
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• 1997.10a
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• pp.261-266
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• 1997

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.5363-5368
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• 2014

This study examined contribution rate on the Soyangho Lake watershed based on the flow regime, and seasonal change was evaluated by calculating the delivery pollution load of the drainage area of Soyangho Lake watershed. According to the contribution rate of the drainage area by the flow regime change, Inbukcheon Creek watershed's SS and T-P entry have recorded abnormal Six month flow and a contribution rate of 46% and 51% during the Low-water flow period. At the same time, the T-P recorded a 49.5% contribution rate and a contribution rate of 48.5% during the Low-water flow period. In sequence, Inbukcheon creek's SS entry recorded a comparatively higher contribution rate than the other drainage area, which are 39.6% and 44.3% during the entire season and 53.8% for T-P, as a result of observing the contribution rate based on the seasonal changes. The T-N at the Naerincheon Creek watershed for the entire season recorded a contribution rate between 39.6% and 44.3%. Overall, Inbukcheon Creek watershed's SS and T-P entry and Naerincheon creek's T-N had a high contribution rate on contaminant spill.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.590-595
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• 1994

Kimchi packed in PP tray was stored at $10^{\circ}C$ to investigate the effect of filling ratio on the quality changes. The quality of Kimchi studied were gas composition in the package, pH, titratable acidity, color, growth of lactic acid bacteria and sensory properties. As the filling ratio increased, there was more $O_{2}$ consumption and $CO_{2}$ evolution measured. Titratable acidity and pH were not significantly affected by the filling ratio. Color change of crushed Kimchi juice was also little affected by the filling ratio. During the storage, L and b values were decreased exponentially, but a value s remained constant. The growth of lactic acid bacteria and sensory scores showed no significant difference according to the filling ratio. Therefore, the filling ratio in packaging of Kimchi seemed to have little influence on the quality changes of Kimchi.

• Journal of the Korea Organic Resources Recycling Association
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• v.22 no.1
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• pp.57-66
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• 2014

The present study was conducted to provide basic data for environmentally friendly treatment of manure using vermicomposting. This was done by investigating the influence of physiochemical property change during the composting period on the survival of earthworms after mixing cow manure in different levels (0(CRH0), 10(CRH10), 20(CRH20), 30(CRH30), and 40%(CRH40)) with the rice hull that is generally added for composting manure. As composting proceeds, earthworms were able to survive in all conditions after 3 weeks. In terms of the C/N ratio by treatment groups, the rice hull mix treatments were significantly higher than the CRH0 treatment. Among rice hull mix treatments, the treatments with 30~40% rice hull level (CRH30 & CRH40) showed the highest ratio out of all composting periods (p<0.05). The C/N ratio in the 3rdweek when earthworms started surviving was 23.26~34.44. As composting progressed, pH and electrolytic conductivity (EC) were the highest in the CRH0 treatment (p<0.05) and tended to decrease with higher proportion of rice hull in the mix. It was found that pH and electrolytic conductivity (EC) that earthworms start to survive are 7.58~7.74 and 0.41~1.17 mS/cm, respectively. To summarize, when composing cow manure with various levels of rice hull mix, all physiochemical property changes turned out to allow the survival of earthworms, but the results suggest that efficient vermicomposting requires the tests to examine the growth and reproduction according to the rice hull mix ratio.