• PNF and Movement
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• v.16 no.1
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• pp.51-58
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• 2018

Purpose: The aim of the present study was to investigate the effects of proprioceptive neuromuscular facilitation (PNF) and taping interventions on balance ability, joint position sense, and ankle joint strength. Methods: Thirty subjects who had experienced an ankle sprain within the previous 3 months participated in this study. The subjects were randomly assigned to a PNF group (n=15) or a taping group (n=15). Before and after the interventions, ankle dorsi-flexion and plantar-flexion strength, joint position error, and total center of pressure movements in one leg while in a standing position were measured. Results: Regardless of the group allocation, ankle dorsi-flexion and plantar-flexion strength significantly improved after the interventions (p<0.05). Compared to preintervention measurements, joint position errors were significantly reduced postintervention (p<0.05). The PNF intervention significantly decreased the total lateral movement of the center of pressure in the one leg standing condition (p<0.05). Conclusion: Both PNF and taping interventions improved joint position sense and ankle joint strength. In common with the findings of a previous study, the PNF intervention improved balance ability. Further study is required to investigate the effects of various PNF and taping interventions on ankle performance in subjects with chronic ankle sprains.

• Journal of the Korea institute for structural maintenance and inspection
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• v.4 no.1
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• pp.101-110
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• 2000

In case heavy rainfall is a key factor of slope failure, the failure zone is usually developed within the depth of 3~5m from the ground surface regardless of the location of the watertable. If rainfall is taken into consideration, it is general that the slope stability analysis is carried out under the assumption that the cut slope is saturated to the slope surface or the watertable elevates to a certain height so that ${\gamma}_{sat}$, the unit weight of saturated soil, is used. However, the analysis method mentioned above can't exactly simulate the variation of pore water pressure in the slope and yields different failure shape. The applicability of slope stability analysis method considering the distribution of pore water pressure within the slope with heavy rainfalls, was checked out after the stability analysis of a lage-scale cut slope in a highway construction site, where surface failure occurred with heavy rainfalls. An appropriate slope stabilization method is proposed on the base of the outcome of the analysis.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.163-170
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• 2005

In this paper, the rock bolts, soil nails with filling grout and the micro-piling with injecting grout by pressure were applied for the stabilization of the cut slopes consisting of sedimentary rocks, igneous rocks and metamorphic rocks respectively. The field measurements and 3-D FEM analyses to find out mobilized tensile stresses of the grouted-reinforcing members installed in the drilled holes were executed on each site. With assuming the increments of the cohesive strength in the improved ground, the back analysis using direct calibration approach of changing the elastic modulus of the ground was used to find out the improved elastic modulus which yields the same tensile stresses from field measurements. The results of back analysis show that the elastic modulus of the improved ground were 4 to 6 times as large as the elastic modulus of original ground. Consequently, the design for slope reinforcement to be more rational, it is proposed that not only the improved cohesive strength is to be used in the incremental ranges on well-known previous proposed data, but also the increased elastic modulus which is about 5 times as large as the original elastic modulus is to be considered in design.

• Wind and Structures
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• v.17 no.3
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• pp.263-274
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• 2013

A numerical technique for fluid-structure interaction, which is based on the finite element method (FEM) and computational fluid dynamics (CFD), was developed for application to an industrial chimney equipped with a pendulum tuned mass damper (TMD). In order to solve the structural problem, a one-dimensional beam model (Navier-Bernoulli) was considered and, for the dynamical problem, the standard second-order Newmark method was used. Navier-Stokes equations for incompressible flow are solved in several horizontal planes to determine the pressure in the boundary of the corresponding cross-section of the chimney. Forces per unit length were obtained by integrating the pressure and are introduced in the structure using standard FEM interpolation techniques. For the fluid problem, a fractional step scheme based on a second order pressure splitting has been used. In each fluid plane, the displacements have been taken into account considering an Arbitrary Lagrangian Eulerian approach. The stabilization of convection and diffusion terms is achieved by means of quasi-static orthogonal subscales. For each period of time, the fluid problem was solved and the geometry of the mesh of each fluid plane is updated according to the structure displacements. Using this technique, along-wind and across-wind effects have been properly explained. The method was applied to an industrial chimney in three scenarios (with or without TMD and for different damping values) and for two wind speeds, showing different responses.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.704-707
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• 2017

The purpose of this study was to examine if complex exercises could improve pressure-pain threshold and postural alignment in university students. Subjects in the CON group did not receive an intervention. Subjects in the EXP1 group were applied stretching exercises after applying hot packs on their both shoulders. Subjects in the EXP2 group were applied complex exercises including stretching, stabilization exercises of shoulder girdle and correction of wrong postures. Changes in pressure-pain threshold in the EXP1 group and EXP2 group were greater than that in the CON group (p<0.05). Changes in VAS scores in the EXP1 group and EXP2 group were greater than that in the CON group (p<0.05). Changes of postural alignment did not significantly differ among three groups (p>0.05). The results of this study indicates that complex exercises including stretching exercises, stabilization exercises of shoulder girdle and correction of wrong postures about neck and scapular can be an effective in reduction of shoulder pain and increase of pressure-pain threshold in women university with shoulder pain.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.11 no.3
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• pp.207-214
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• 2017

The problem of trunk stability is a major factor in back pain.. Abdominal draw in maneuver(ADIM), One of the trunk stabilization exercises to relieve lumbar instability, is a method of inducing selective contraction of the transverse abdominis associated with anticipatory posture control among the abdominal stabilization muscles. ADIM is usually performed with a visual feedback by applying a pressure biofeedback unit(PBU) under the lumbar at the supine position, which is not functional compared to the sitting position. This study was conducted to investigate the effect of ADIM applied in supine and sitting position on 31 healthy men and women. In each posture, muscle activity was measured by rectal abdominis (RA), external oblique (EO), transverse abdominis (TrA)/internal obilique (IO) and erector spinae (ES) using wireless EMG. In the result, there was no significant difference between RA and EO between the two postures and there was a significant difference between TrA / IO and ES. In both postures, the activity of TrA/IO was higher than that of RA, and the effect of ADIM was shown to be the same, whereas TrA/IO and ES showed higher activity in sitting position. This means that the activity of the muscles involved in the postural stability and lumbar stability is increased further in the sitting position. Therefore, ADIM in sitting, which can be applied more easily in daily life, is useful for improving lumbar stability.

• Journal of Chest Surgery
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• v.22 no.2
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• pp.212-219
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• 1989

We utilized pulmonary artery pressure monitoring system in risky patients for preventing the postoperative pulmonary hypertensive crisis and for sampling the mixed venous blood. And this mixed venous blood oxygen saturation [MVSO2] or partial pressure [MVPO2]tells us many meaningful patients state. We selected 59 cyanotic congenital heart diseased patients, who were operated in our hospital from Nov. 1987 to Oct. 1988, in the Department of Thoracic and Cardiovascular Surgery, Seoul National University Children\ulcorner Hospital, who had pulmonary artery pressure monitoring catheter and who made us know their mixed venous oxygen condition. We found that there was no close relationship between MVPO2 and Cardiac Index [C.I.] during early postoperative period, but on the first and second day after operation the correlation coefficient was increased as r=0.35[p=0.008], r=0.78[p=0.0001]. So we concluded that the correlation between MVPO2 and C.I. was more reliable with time going as hemodynamic stabilization. And we experienced no survivors whose MVPO2 was under 20 torr, but that was not the only factor for death. From these results, we conclude that we can consider the MVPO2 [or MVSO2] representing C.I. after stabilized postoperative condition of the open heart surgery patients, but during early postoperative period, in addition to this MVPO2, we should do also apply other parameter such as urine output, arterial blood pressure, left atrial pressure and pulmonary arterial pressure for exact estimation of the patients status.

• Geotechnical Engineering
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• v.13 no.5
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• pp.101-124
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• 1997

The root pile system is insitu soil reinforcement technique that uses a series of reticulately installed micropiles. In terms of mechanical improvement by means of grouted reinform ming elements, the root pile system is similar to the soil nailing system. The main difference between root piles and soil nailing are due to the fact that the reinforcing bars in root piles are normally grouted under high pressure and that the alignments of the reinforcing members differ. Recently, the root pile system has been broadly used to stabilize slopes and retain excavations. The accurate design of the root pile system is, however, a very difficult tass owing to geometric variety and statical indetermination, and to the difficulty in the soilfiles interaction analysis. As a result, moat of the current design methods have been heavily dependent on the experiences and approximate approach. This paper proposes a quasi-three dimensional method of analysis for the root pile system applied to the stabilization of slopes. The proposed methods of analysis include i) a technique to estimate the change in borehole radium as a function of the grout pressure as well as a function of the time when the grout pressure is applied, ii) a technique to evaluate quasi -three dimensional limit-equilibrium stability for sliding, iii) a technique to predict the stability with respect to plastic deformation of the soil between adjacent root piles, and iv) a quasi -three dimensional finite element technique to compute stresses and dis placements of the root pile structure barred on the generalized plane strain condition and composite unit cell concept talon형 with considerations of the group effect and knot effect. By using the proposed technique to estimate the change in borehole radius as a function of the grout pressure as well as a function of the time, the estimations are made and compar ed with the Kleyner 8l Krizek's experimental test results. Also by using the proposed quasi-three dimensional analytical method, analyses have been performed with the aim of pointing out the effects of various factors on the interaction behaviors of the root pile system.

• Physical Therapy Rehabilitation Science
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• v.11 no.2
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• pp.136-144
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• 2022

Objective: This study was to identify the effect of pressure biofeedback applied in various postures that allow the application of abdominal drawing-in. Design: A cross sectional study. Methods: The study intended to compare changes in the thickness of abdominal muscles between different postures when abdominal drawing-in was performed using a pressure biofeedback unit in five postures and to compare differences in terms of measures such as the transverse abdominis's preferential activation ratio(PAR). Data measured from 30 healthy individuals were used for data analysis. A paired t-test and repeated measures analysis of variance was performed to compare the thickness of each abdominal muscle. Results: The transverse abdominis's and internal oblique's thickness showed statistically significant differences in all postures when abdominal drawing-in (p<0.05). In the comparison between the postures, statistically significant differences were observed between the positions of hook-lying and wall support standing and between supine and wall support standing and between hook-lying and sitting (p<0.05). In terms of the transverse abdominis's PAR in each posture, statistically significant differences were observed between hook-lying and quadruped, hook-lying and sitting, hook-lying and wall support standing, quadruped and supine, sitting and supine, as well as wall support standing and supine (p<0.05). Conclusions: When abdominal drawing-in using pressure biofeedback unit is performed for stabilization exercises, selecting and applying specific postures according to targeted muscles and the subject's functional ability will help provide a more efficient and accurate intervention.

• PNF and Movement
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• v.15 no.3
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• pp.353-360
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• 2017

Purpose: This study aimed to measure static balance of low back pain patients while one-leg standing in abdominal compression belts. Methods: The study included 40 adult males and females at J university, divided into a low back pain patient group and a normal group through the Oswestry disability questionnaire (ODQ). The subjects were instructed to hold a one-leg standing posture for 15 seconds on a balance measurement plate while wearing an abdominal compression belt. Shifting distance (0.1 cm), mean velocity (cm/s), pressure, and contact area were analyzed using BioRescue (BioRescue, RMINGEIEIRIE, Rodez, France). The average value was used to measure the result 3 times for each condition. Results: Both normal and low back pain groups significantly decreased in the speed of sway while wearing the abdominal compression belt. Furthermore, the pressure of the center of motion significantly decreased in the low back pain groups while wearing abdominal compression belt. However, there were no significant differences in the speed of sway or the pressure of center of motion between groups after wearing the abdominal pressure belt. Conclusion: These results suggest that abdominal compression belts are one option for improving balance temporarily. However, balance after wearing abdominal compression vests depends on onset of back pain, age, and symptoms of pain in the groups with low back pain. Further research is needed to investigate muscle activity, dynamic balance, and the effect of the period of wearing abdominal compression belts in the variety of low back pain patients.