• Aerospace Engineering and Technology
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• v.9 no.2
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• pp.185-192
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• 2010

Design of velocity-compounded turbine for 75ton class LRE turbopump application and pressure compounded turbine for 30ton class LRE turbopump has been performed. 1D calculation and CFD analysis were conducted in determining blade and flow passage shape of velocity compounded turbine iteratively. Finally, 23.1% improved specific power and 5% reduced weight turbine to the original design was developed. In case of pressure-compounded supersonic turbine design, rotational speed was increased by 50% and the effect of carryover ratio, 2nd nozzle installation angle, leakage flow of 2nd nozzle, and work sharing factor was studied. Final 1D design resulted 36% increased specific power and 51% reduced weight comparing to the original single-row impulse turbine. It is anticipated that nozzle flow path design will be very important for the accomplishment of expected performance of pressure-compounded turbine and nozzle shape optimization will be conducted through the CFD analysis.

• Journal of Korean Physical Therapy Science
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• v.10 no.2
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• pp.29-36
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• 2003

The purpose of this study was to investigate the effects of height of shoe lifts on gait and balance in hemiplegic patients. Twenty-two hemiplegic patients who were receiving rehabilitation treatment at Hanyang University Seoul Hospital and National Rehabilitation Center participated in this study from November 8, 2002 through March 20, 2003. Data analysis using repeated measures ANOVA and Bonferroni method, for a post-test. The results of this study were as follows : First, shoe lift on the height of 3mm, 6mm, 9mm, 12mm significantly improved, as compared to un-lift status, in gait velocity, PCI, weight bearing(p<0.05). Second, gait velocity was significantly difference between 3mm and 9mm, and between 3mm and 12mm, and weight bearing on the affected side was significantly difference between 3mm and 12mm, and between 6mm and 12mm(p<0.05). Third, after the shoe lift removed was significantly improved in gait velocity, PCI, weight bearing than before shoe lifts being added(p<0.05). These results suggest that shoe lift on the unaffected side may helpful for improving the gait efficiency and symmetrically of weight bearing. Furthermore, persistence of gait efficiency and symmetrically of weight bearing after removing the shoe lift suggests carryover effect of gait training on shoe lift of unaffected side.

• Physical Therapy Korea
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• v.21 no.2
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• pp.57-66
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• 2014

The objective of this study was to determine the duration of maintained calf muscle flexibility gained in young adults with calf muscle tightness, as measured by increases in ankle active and passive dorsiflexion range of motion (DFROM) after three stretching interventions. Twenty subjects (5 men and 15 women) with calf muscle tightness received the following three stretching interventions in one leg (assigned at random): static stretching (SS), eccentric training on stable surface (ETS), and eccentric training on unstable surfaces (ETU). The subjects received all three interventions to the same leg, applied in a random order. Each intervention had a break of at least 24 h in-between, in order to minimize any carryover effect. Each intervention used two types of stretching: with the calf muscle stretched and both knees straight, and with the knee slightly bent in order to maximize the activation of the soleus muscle. All three interventions were performed for 200 seconds. We measured the duration of maintained calf muscle flexibility through active and passive ankle DFROM before intervention, immediately after intervention (time 0), and then 3, 6, 9, 15, and 30 min after intervention. We found a difference in the duration of maintained calf muscle flexibility between the three interventions. In the ETS and ETU interventions, a significant improvement in calf muscle flexibility, both ankle active and passive dorsiflexion ranges of motion (ADFROM and PDFROM), was maintained for 30 min. In the SS intervention, however, ADFROM before 9 min and PDFROM before 6 min were statistically different from the baseline. Our results suggest that ETS and ETU may be more effective than SS for maintaining calf muscle flexibility in young adults.

• Analytical Science and Technology
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• v.34 no.6
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• pp.259-266
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• 2021

Cannabis (Marijuana) is one of the most widely used drugs in the world, and its distribution has been controlled in South Korea since 1976. Identification of 11-nor-Δ⁹-carboxy-tetrahydrocannabinol (THCCOOH) in urine can provide important proof of cannabis use, and it is considered scientific evidence in the forensic field. In this study, we describe a simultaneous quantitative method for identifying THCCOOH and THCCOOH-glucuronide in urine, using simple liquid-liquid extraction (LLE), and liquid chromatography-tandem mass spectrometry (LC-MS/MS). THCCOOH-D₃ and THCCOOH-glucuronide-D₃ were used as internal standards. Validation results of the matrix effect, as well as recovery, linearity, precision, accuracy, process efficiency, and stability were all satisfactory. No carryover, endogenous or exogenous interferences were observed. The limit of detection (LOD) of THCCOOH and THCCOOH-glucuronide were 0.3 and 0.2 ng/mL, respectively. The developed method was applied to 28 authentic human urine samples that tested positive in immunoassay screening and gas chromatography/mass spectrometry (GC/MS) tests. The ranges of concentrations of THCCOOH and THCCOOH-glucuronide in the samples were less than LOQ~266.90 ng/mL and 6.43~2133.03 ng/mL, respectively. The concentrations of THCCOOH-glucuronide were higher than those of THCCOOH in all samples. This method can be effectively and successfully applied for the confirmation of cannabinoid use in human urine samples in the forensic field.

• The Journal of Internal Korean Medicine
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• v.28 no.3
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• pp.492-501
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• 2007

Objectives : This study was executed in order to evaluate the effects of electroacupuncture on upper-extremity spasticity control in stroke patients. Methods : Eighteen patients with stroke were enrolled and classified into two groups, the study and control group. The control group did not receive any oriental medical treatment. In the study group, the electroacupuncture points were applied to Kokt'aek (PC3) and $Ch'{\u{o}}ch'{\u{o}}n$ (PC2), Naegwan (PC6) and $Ch'{\u{o}}kt'aek$(LU5) of the affected limb. H-reflexl M-response ratio (HIM ratio), modified Ashworth scale (MAS) and Fugl-Meyer motor function assessment (FMA) were used for evaluation of spasticity control before electroacupuncture, within two hours after electroacupuncture, and at two weeks. Results : In MAS, the study group declined more than the control group. but there was no statisticallysignificant consideration. In H/M ratio. the study group was more efficient than the control group. and spasticity decreased successively during the series in the study group. In FMA, motor function in the study group improved more than in the control group and motor function in the study group increased successively during the series. Conclusions : These results showed that electro acupuncture was a useful method to decrease upper-extremity spasticity in patients with stroke. Further studies are needed to explore more cases and the long-lasting carryover effects on upper-extremity spasticity in electroacupuncture.