• Journal of the Korean Magnetics Society
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• v.4 no.1
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• pp.32-38
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• 1994

We have investigated the effects of sputtering Ar gas pressure on magnetic and magneto-optical properties in compositionally modulated Co/Pt superlattice thin films. The samples were prepared by dc magnetron sputtering. Sputtrering Ar gas pressure was varied from 2 to 30 mTorr. The microstructure of the samples was examined by scanning electron microscope and the x-ray diffractometry. The magnetization, the Kerr rotation angle, and the reflectivity of the samples were measured. The columnar structure was developed, and the coercivity was drasti- cally increased, when the sputtering Ar gas pressure was higher than 20 mTorr. We explained that the variation of the magnetization, the Kerr rotation angle, and the reflectivity was related with the microstructure influenced by the variation of the Ar gas pressure.

• The Journal of Korean Society for Neurotherapy
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• v.22 no.3
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• pp.31-36
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• 2018

Purpose The purpose of this study was to investigate the effects of contact handorientation response(CHOR) during sit-to-stand(STS) in people with stroke. Methods The subjects of the study were Thirty hemiplegia participated (Rt. hemiplegia/Lt. hemiplegia: 15/15, mean age: $65.82{\pm}8.53$) in this study. The analysis of muscles activation (rectus femoris, biceps femoris, tibialis anterior, gastrocnemius) distribution was conducted by the EMG, and the analysis of foot pressure distribution was conducted by the resistive pressure sensor. Hemiplegic stroke patients were instructed to perform STS three times with the non-affected side hand and affected side hand on the table. Results There was a significant positive correlation between rectus femoris, tibialis anterior muscle activation and affected side hand contact during STS(p<0.05). The STS correlated with the foot pressure in the affected side hand contact(p<0.05). Conclusion AS a result, CHOR during STS is related to muscle activation and the characteristics of foot pressure. This information was observed in the affected side hand contact on the table, suggestion that rehabilitation programs should be implemented.

• Journal of Medicine and Life Science
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• v.15 no.2
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• pp.56-61
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• 2018

Advances in medical technology has enabled better management of complicated and chronic wounds. Negative-pressure wound therapy (NPWT) is a novel dressing technique that uses negative pressure to drain exudates and blood from wounds. NPWT increases local blood flow and promotes reduction of edema and wound healing and is suitable for a variety of wounds. It is associated with few adverse effects and shows excellent efficacy and cost-effectiveness. NPWT promotes rapid growth of granulation tissue and wound contraction; thus, it is more advantageous than general dressings as it reduces the size skin of grafts or flaps required for repair, and patients with chronic wounds can be treated as outpatients. We investigated the general usage and mechanism of NPWT, its clinical applications and adverse effects.

• The Journal of Korean Physical Therapy
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• v.33 no.3
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• pp.162-167
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• 2021

Purpose: A hyperextended knee is described as knee pain associated with an impaired knee extensor mechanism. Additionally, a hyperextended knee may involve reduced position sense of the knee joint that decreases the individual's ability to control end-range knee extension movement. The purpose of this study was to investigate the effects of visual biofeedback information for plantar pressure distribution on knee joint angle and lower extremity muscle activities in participants with hyperextended knees. Methods: Twenty-three participants with hyperextended knees were recruited for the study. Surface electromyography signals were recorded for the biceps femoris, rectus femoris, gastrocnemius, and tibialis anterior muscle activities. The plantar pressure distribution was displayed and measured using a pressure distribution measuring plate. Knee joint angle kinematic parameters were recorded using a motion analysis system. The visual biofeedback condition was the point at which the difference between the forefoot and backfoot plantar foot pressure on the monitor was minimized. The Wilcoxon signed-rank test was used to determine the significance between the visual biofeedback condition and the preferred condition. Results: The knee joint angle was significantly decreased in the visual biofeedback condition compared to that in the preferred condition (p<0.05). The rectus femoris and gastrocnemius muscle activities were significantly different between the visual biofeedback and preferred conditions (p<0.05). Conclusion: The results of this study showed that visual biofeedback of information about plantar pressure distribution is effective for correcting hyperextended knees.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.1C
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• pp.53-63
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• 2010

Since the water retention curve is considered as a major parameter to evaluate the unsaturated ground or soils, overburden pressure and clay content on soils underneath ground surface have not been considered for estimating water retention characteristics. Therefore, a need exists that the effect of overburden pressure and clay content on water retention characteristics was assessed in typical weathered soils found in Korea. Soil-Water Characteristic Curve and the unsaturated hydraulic conductivity were estimated using water retention characteristics under the condition of different overburden pressure, clay content, and de-saturation path. Then, these effects are evaluated with the results of SWCC tests from the laboratory. In addition to that, the unsaturated moisture capacity and diffusivity of each case is discussed.

• Journal of Korea Foundry Society
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• v.40 no.2
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• pp.34-42
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• 2020

The effects of the initial balancing pressure, filling pressure and maximum build-up pressure on the casting characteristics of the thick-wall thickness casting during the counter-pressure casting process were investigated. Water model experiment and a computer simulation were carried out to evaluate the characteristics during the filling and solidification stages in counter-pressure casting (CPC); as a reference, the low-pressure casting (LPC) process was used. The average dendrite cell size decreased with an increase in the solidification rate and maximum build-up pressure. A turbulent flow occurred during the filling stage of the LPC process, resulting in the formation of inner gas, while a lamellar flow pattern dominated during the CPC process and was more evident with an increase in the initial balancing pressure, improving the mechanical properties of the castings.

• Journal of Korean Critical Care Nursing
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• v.3 no.2
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• pp.1-11
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• 2010

Purpose: This study was designed to identify the factors affecting healing of Stage 2 pressure ulcer in an acute care facility in Korea. Methods: 286 Stage 2 pressure ulcers of 145 patients were examined. Data were collected in the period between October $1^{st}$, 2006 and September $30^{th}$, 2007. Data were analyzed with Kaplan-Meier survival analysis for cumulative recovery rate of Stage 2 pressure ulcers. Cox proportional hazard model was used to examine effects of multiple variables simultaneously. Results: Out of 286 initial Stage 2 pressure ulcers, 204 (71.3%) pressure ulcers healed completely. The median time to heal was 15 days according to Kaplan-Meier survival analysis. Cox proportional hazard model showed that the Stage 2 pressure ulcers healed more quickly when pressure redistribution surfaces were used (p<.001, HR=2.184), patients were administered with vitamins (p= .038, HR=1.451), and the size of the pressure ulcers were small (${\leq}3.0cm^2$, p= .006, HR=1.765). Conclusion: The factors contributing to the healing of Stage 2 pressure ulcer in an acute care setting were the application of pressure redistribution surface, small ulcer size (${\leq}3.0cm^2$), and the administration of vitamins.

• Journal of the Society of Naval Architects of Korea
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• v.57 no.4
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• pp.198-206
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• 2020

In this study, the dynamic structural behavior of pressure vessels due to pressure pulse initiated by implosion of neighbouring airbacked equipments including Unmanned Underwater Vehicles (UUV), sensor system, and so on were dealt with for the structural design and safety assessment of pressure hulls of submarine. The dynamic buckling and collapse responses of pressure vessel in deep sea were investigated considering the effects of initial hydrostatic pressure and fluid-structure interactions. The governing equations for circular cylindrical shells were formulated theoretically assuming a relatively simple displacement fields and the derived nonlinear simultaneous ordinary differential equations were analysed by developed numerical solution algorithm. Finally, the introduced safety assessment procedures for the dynamic buckling behaviors of pressure hulls due to implosion pressure pulse were validated by comparing the theoretical analysis results with those of experiments for examples of simple cylinders.

• Physical Therapy Korea
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• v.4 no.2
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• pp.36-50
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• 1997

The purpose of this study was to compare the effects of high intensity, high frequency microcurrent electrical neuromuscular stimulation(MENS) of auricular and somatic acupuncture points and low intensity, low frequency microcurrent electrical neuromuscular stimulation(MENS) of auricular and somatic acupuncture points on experimental pressure threshold at the elbow according to the time. Fifty healthy adults, aged 19 to 26 years, were assigned randomly to one of five groups: 1) the high intensity, high frequency somatic group(n=10) received MENS to somatic acupuncture points, 2) the high intensity, high frequency auricular group(n=10) received MENS to auricular acupuncture points, 3) the low intensity, low frequency somatic group(n=10) received MENS to somatic acupuncture points, 4) the low intensity, low frequency somatic group(n=10) receive MENS to somatic acupuncture points, and 5) the placebo group(n=10) received placebo treatment and served as controls. Pressure threshold was measured before, after, 5 minutes, 10 minutes and 15 minutes. Pressure threshold has increased significantly(p<.05) in the high intensity, high frequency auricular group following treatment after 5 minutes, with no statistically significant differences in pressure threshold change scores among five groups, Only the high intensity, high frequency auricular group demonstrated statistically significant change score in pressure threshold following treatment after, 5 minutes, 10 minutes and 15 minutes after compared to the placebo group. The results indicated that MENS applied to the high intensity, high frequency auricular group increases pressure threshold.

• Journal of the Korean Society of Physical Medicine
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• v.15 no.1
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• pp.105-112
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• 2020

PURPOSE: This study examined the effects of Interactive Metronome training on the plantar pressure and fall efficacy in chronic stroke patients. METHODS: Twenty-two hemiplegic patients were allocated randomly to an experimental group and control group. The experimental group received conventional physical therapy and emphasized weight-bearing interactive metronome training, whereas the control group received conventional physical therapy. The training was performed three times per week, 40 minutes per each session, for a total of seven weeks. The plantar pressure was assessed using the contact area and contact pressure, whereas the fall efficacy was assessed using the FES (Fall Efficacy Scale), ABC (Activities-specific Balance Confidence scale) and FOFQ (Fear of Falling Questionnaire). RESULTS: After training, a significant increase was observed in the paretic side of the contact area and the paretic and non-paretic side of contact pressure in both groups (p<.05). The between-group differences in the changes before and after training were statistically significant in the paretic side of the contact pressure (p<.05). After training, both the FES of the between-group and ABC of the experimental group were increased significantly (p<.05), but the between-group differences in the changes before and after training were not statistically significant in the FES, ABC, and FOFQ (p>.05). CONCLUSION: Interactive Metronome training is considered an effective treatment for improving the contact pressure of the paretic side in chronic stroke patients.