• 유체기계공업학회:학술대회논문집
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• 2004.12a
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• pp.140-150
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• 2004

In this study, the effect of relative position of the blade for the fixed vane has been investigated on blade surface heat transfer. The experiments were conducted in a low speed stationary annular cascade, and heat transfer of blade was examined for six positions within a pitch. Turbine test section has one stage composed of sixteen guide vanes and blades. The chord length of the tested blade is 150 mm and the mean tip clearance of the blade having flat tip is about $2.5\%$ of the blade chord. For the detailed mass transfer measurements on the blade surfaces, a naphthalene sublimation technique was used. The inlet flow Reynolds number is fixed to $1.5{\times}10^5$. Complex heat transfer characteristics are observed on the blade surface due to various flow characteristics, such as separation bubble, relaminarization, transition to turbulence and leakage vortices. The distributions of velocity and turbulence intensity change significantly with the relative position due to the blockage effect of the blade. This causes the variation of heat transfer patterns on the blade surface. The results show that the flow near the leading edge get highly disturbed and deflected toward the either side of the blade when the blade leading edge is positioned close to the trailing edge of the vane. Therefore, separation bubble disappears on the pressure side and overall heat transfer on the relaminarization region is increased. But, due to reduced tip gap flow at the upstream region, the effect of leakage flow on the upstream region of the blade surface is weakened. Thus, the heat transfer characteristics significantly change with the blade positions.

• The Journal of Korean Physical Therapy
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• v.11 no.3
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• pp.1-12
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• 1999

The aim of this study is to examine the sensitivity and characteristics of electromyography abnormalities detected by using various paramenters in patients with lumbosacral radiculopathies. EMG is widely used for disgnosing and localizing the level of radiculopathy. The results of the study were as follow : 1. In electromyography, L5 radiculopathy usa 95 cases(51.690). S1 radiculopathy was $45m(24.5\%)$ L4 radiculopathy was 18cases $(9.8\%)$, and L2, 3 radiculopathy was 8cases$(4.3\%)$. Remains 18cases$(9.8\%)$ had no definite radiculopathy. 2. Peroneal and tibial motor nerve conduction velocity studies were not significant as compared to the side to side. 3. Latency of H-reflex in L5 radiculopathy was $30.55\pm2.47$ in affected side, $29.47\pm2.29$ in unaffected side, in S1 radiculopathy was $33.00\pm2.03$ in affected side, R30.18\pm2.21$ in unaffected side. It was statistically significant(p<0.01). H-reflex mean difference of S1 radiculopathy group was significantly prolonged as compared to the L5 and S1 radiculopathies(p<0.001). 4. In L2, 3 radiculopathy, abnormal spontaneous activities and motor unit action potentials were showed high sensitivity in upper lumber paraspinal, hip adductors, quadriceps and iliopsoas muscles. 5. In L4 radiculopathy, lower lumbar paraspinal, tibialis anterior, quadriceps muscles were showed high sensitivity. 6. In L5 radiculopathy, lower lumbar paraspinal, extensor hallucis longus, extensor digitorum longus, peroneus longus, extensor digitorum brevis, gluteus maximus, tensor fasciae latae muscles were showed high sensitivity. 7. In S1 radiculopathy, lower lumbar paraspinal, gluteus maximus, peroneus longus, soleus, abductor hallucis, hamstrings, extensor digitorum brevis, extensor hallucis lognus, gastrocnemius muscles were showed high sensitivity.

• PNF and Movement
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• v.18 no.2
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• pp.215-222
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• 2020

Purpose: The study investigated the effect on chronic stroke patients' balance of a weight shift to the affected side using an insole on the less affected side during treadmill walking training. Methods: The subjects were 7 patients who had been diagnosed with stroke 6-24 months prior to the study. In each case, an insole was applied on the patient's less affected side during treadmill walking training. Each training session lasted 30 minutes and was undertaken 5 times per week for 4 weeks. Biorescue equipment that measures shifts in center of pressure was used to assess balance ability as measured by the Korea-Berg balance scale (K-BBS) before and after each training intervention. The Wilcoxon signed-rank test was used to evaluate within-group effects. Results: The results revealed statistically significant before and after differences in area, pressure, length, and mean velocity of the balance test and on K-BBS (p < 0.05). Conclusion: In chronic stroke patients, using an insole to adjust the height of the shoe on the less affected side is an effective means of increasing weight-shifting on the paralyzed side during treadmill gait training.

• Journal of Korean Neurosurgical Society
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• v.46 no.3
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• pp.239-244
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• 2009

Objective : Cerebral vasospasm leading to cerebral ischemic infarction is a major cause of morbidity and mortality in the patients who suffer with aneurysmal subarachnoid hemorrhage. Despite adequate treatment, some patients deteriorate and they develop symptomatic vasospasm. The objective of the present study was to investigate the efficacy and clinical outcome of intraarterial nimodipine infusion on symptomatic vasospasm that is refractory to hemodynamic therapy. Methods : We retrospectively reviewed the procedure reports, the clinical charts and the transcranial doppler, computed tomography and digital subtraction angiography results for the patients who underwent endovascular treatment for symptomatic cerebral vasospasm due to aneurysmal SAH. During the 36 months between Jan. 2005 and Dec. 2007, 19 patients were identified who had undergone a total of 53 procedures. We assessed the difference in the arterial vessel diameter, the blood flow velocity and the clinical outcome before and after these procedures. Results : Vascular dilatation was observed in 42 of 53 procedures. The velocities of the affected vessels before and after procedures were available in 33 of 53 procedures. Twenty-nine procedures exhibited a mean decrease of 84.1 cm/s. We observed clinical improvement and an improved level of consciousness with an improved GCS score after 23 procedures. Conclusion : Based on our results, the use of intraarterial nimodipine is effective and safe in selected cases of vasospasm following aneurysmal SAH. Prospective, randomized studies are needed to confirm these results.

• Journal of Mechanical Science and Technology
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• v.19 no.8
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• pp.1632-1648
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• 2005

The effects of Reynolds number on the non-nulling calibration of a typical cone-type five-hole probe have been investigated for the representative Reynolds numbers in turbomachinery. The pitch and yaw angles are changed from - 35 degrees to 35 degrees with an angle interval of 5 degrees at six probe Reynolds numbers in range between $6.60{\times}10^3\;and\;3.17{\times}10^4$. The result shows that not only each calibration coefficient itself but also its Reynolds number dependency is affected significantly by the pitch and yaw angles. The Reynolds-number effects on the pitch- and yaw-angle coefficients are noticeable when the absolute values of the pitch and yaw angles are smaller than 20 degrees. The static-pressure coefficient is sensitive to the Reynolds number nearly all over the pitch- and yaw-angle range. The Reynolds-number effect on the total-pressure coefficient is found remarkable when the absolute values of the pitch and yaw angles are larger than 20 degrees. Through a typical non-nulling reduction procedure, actual reduced values of the pitch and yaw angles, static and total pressures, and velocity magnitude at each Reynolds number are obtained by employing the calibration coefficients at the highest Reynolds number ($Re=3.17{\times}10^4$) as input reference calibration data. As a result, it is found that each reduced value has its own unique trend depending on the pitch and yaw angles. Its general tendency is related closely to the variation of the corresponding calibration coefficient with the Reynolds number. Among the reduced values, the reduced total pressure suffers the most considerable deviation from the measured one and its dependency upon the pitch and yaw angles is most noticeable. In this study, the root-mean-square data as well as the upper and lower bounds of the reduced values are reported as a function of the Reynolds number. These data would be very useful in the estimation of the Reynolds-number effects on the non-nulling calibration.

• Korean Journal of Medicinal Crop Science
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• v.20 no.2
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• pp.85-88
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• 2012

This study evaluated the germination rate of $Rheum$ $palmatum$ L. in Korea as affected by storage temperature, germination temperature, and a soaking treatment. The germination rate of $R.$ $palmatum$ L. stored at various conditions for 8 weeks was > 60%. The highest germination rate occurred at $25^{\circ}C$. The germination point of $R.$ $palmatum$ L. with soaking was started 1 day after application, and non soaked seeds germinated in 2 days. When $R.$ $palmatum$ L. was soaked with water, the germination rate was lower, but mean germination velocity was the highest. These results may help our understanding of variations in germination characteristics for seeds treated under different germination conditions.

• Asian Journal of Atmospheric Environment
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• v.2 no.1
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• pp.1-13
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• 2008

A numerical simulation method has been developed to predict atmospheric flow and stack gas diffusion using a calculation domain of several km around a stack under complex terrain conditions containing buildings. The turbulence closure technique using a modified k-$\varepsilon$-type model under a non hydrostatic assumption was used for the flow calculation, and some of the calculation grids near the ground were treated as buildings using a terrain-following coordinate system. Stack gas diffusion was predicted using the Lagrangian particle model, that is, the stack gas was represented by the trajectories of released particles. The numerical model was applied separately to the flow and stack gas diffusion around a cubical building and to a two-dimensional ridge in this study, before being applied to an actual terrain containing buildings in our next study. The calculated flow and stack gas diffusion results were compared with those obtained by wind tunnel experiments, and the features of flow and stack gas diffusion, such as the increase in turbulent kinetic energy and the plume spreads of the stack gas behind the building and ridge, were reproduced by both calculations and wind tunnel experiments. Furthermore, the calculated profiles of the mean velocity, turbulent kinetic energy and concentration of the stack gas around the cubical building and the ridge showed good agreement with those of wind tunnel experiments.

• Journal of Ginseng Research
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• v.34 no.3
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• pp.212-218
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• 2010

Korean red ginseng (KRG) has been shown to enhance endothelium-dependent vasorelaxation in experimental animals; however, little is known about its pharmacological effects on vascular stiffness in patients with coronary artery disease (CAD). This randomized, double-blind, placebo-controlled crossover trial was carried out to determine whether KRG has beneficial effects on arterial stiffness, cardiovascular risk factors such as plasma lipid profiles and blood pressure (BP), and Rho-associated kinase (ROCK) activity. Twenty patients (mean age, 62.5 years) with stable angina pectoris were given KRG (2.7 g/day) and a placebo alternatively for 10 weeks. Blood biochemical analysis and pulse wave velocity (PWV) recording were performed on day 0 and after the completion of each treatment. ROCK activity was assessed based on the level of phospho-$Thr^{853}$ in the myosin-binding subunit of myosin light chain phosphatase, determined by Western blot analysis of peripheral blood mononuclear cells. KRG significantly decreased the systolic BP, brachial ankle PWV, and heart femoral PWV in the patients (all p<0.05), but did not significantly alter the serum lipid profiles, including triglycerides and total, high-density lipoprotein, and low-density lipoprotein cholesterol levels. The ROCK activity tended to decrease (p=0.068) following KRG treatment. The placebo did not significantly alter any of the variables. In conclusion, KRG decreased systolic BP and arterial stiffness, probably via the inhibition of ROCK activity, in patients with CAD, but had a neutral effect on serum lipid profiles. Our data suggest that KRG has a therapeutic effect on CAD.

• Annals of Clinical Neurophysiology
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• v.15 no.2
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• pp.48-52
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• 2013

Background: Meralgia paresthetica (MP) is a mononeuropathy affecting the lateral femoral cutaneous nerve. The disease is often diagnosed clinically, but electrophysiological tests play an important role. The aim of this study is to clarify clinical characteristics of MP as well as the role of sensory nerve conduction study (NCS) in the diagnosis of MP. Methods: Sixty-five consecutive patients with clinical diagnosis of MP between March 2001 and June 2012 were retrospectively reviewed at a single tertiary center. General demographics, clinical characteristics and sensory NCS findings were investigated. Measurements of sensory NCS included the baseline-to-peak amplitude, side-to-side amplitude ratio and the conduction velocity. To compare between the normal and abnormal NCS groups, independent t-tests and chisquare test were performed. Results: Sixty-five patients had male predominance (56.9%) with mean age of $48.4{\pm}13.4$ years (range: 16-75). Seven patients (13.5%) had undergone operation or procedure before the symptom onset. The sensory nerve action potentials were obtainable in 52 (80%) of 65 clinically diagnosed MP patients. Sensory NCS revealed abnormalities in 38 patients (73.1%), and others (n=14, 26.9%) showed normal findings. Between the normal and abnormal NCS groups, there is no statistically significant difference on demographics or clinical features. Conclusions: We clarify the clinical features and sensory NCS findings of MP patients. Due to several limitations of sensory NCS, the diagnosis of MP could be accomplished both clinically and electrophysiologically.

• Physical Therapy Korea
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• v.13 no.4
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• pp.47-55
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• 2006

The purpose of this study was to compare the static balance of standing position between adolescent idiopathic scoliosis (AIS) and a normal group that were aged-matched. There were forty subjects included in this study. Twenty-seven healthy subjects (age, $13.9{\pm}1.2$ yrs; height, $161.9{\pm}7.5$ cm; weight, $52.2{\pm}7.7$ kg) and thirteen AIS subjects (age, $14.2{\pm}2.2$ yrs; height, $161.5{\pm}8.7$ cm; weight, $48.1{\pm}8.1$ kg) were participated in the study. The thirteen subjects in the AIS group had a major Cobb angle between $20.1^{\circ}$ and $49^{\circ}$. Each group was tested with the Balance Performance Monitor (BPM). The parameters for static balance were sway area, sway path, max velocity, mean balance, anterior-posterior angle, and left-right angle of each group with their eyes opened and again with their eyes closed. Both sides of the forward reach test and the lateral reach test were also performed on each group. Results from the BPM tested showed significantly increases in all parameters of static balance with those patients with AIS under the conditions where eyes were opened and closed. In the right and left forward reach test, there was no significant difference between normal and AIS groups. However, in the lateral reach test with right and left direction, there were significant differences between normal and AIS groups. For the normal subjects, there were significant differences in the parameters with sway path and anterior-posterior sway angle between the eyes opened and closed. However, there were no significant differences in the all parameters between eyes opened and closed for the AIS subjects. These results suggest that, balance programs could be used in the rehabilitation setting for intervention of AIS and evaluation of AIS. Further study is needed to measure many patients with AIS and other functional balance scales for clinical application.