• Journal of Aerospace System Engineering
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• v.18 no.1
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• pp.1-10
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• 2024

In a previous study, a structure of a superplastic yoke consisting of a thin FR4 layer laminated with viscoelastic tape on both sides of a shape memory alloy (SMA) was proposed to reduce residual vibration generated by a deployable solar panel during high motion of a satellite. Damping properties of viscoelastic tapes will change with temperature, which can directly affect vibration reduction performance of the yoke. To check damping performance of the yoke at different temperatures, free damping tests were performed under various temperature conditions to identify the temperature range where the damping performance was maximized. Based on above temperature test results, this paper predicts temperature of the yoke through orbital thermal analysis so that the yoke can have effective damping performance even if it is exposed to an orbital thermal environment. In addition, the thermal design method was described so that the yoke could have optimal vibration reduction performance.

• Journal of Korean Orthopaedic Sports Medicine
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• v.9 no.2
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• pp.109-113
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• 2010

Purpose: To evaluate the efficacy of ultrasound guided injection of prolotherapy and steroid mixture injection in patients with adhesive capsulitis. Materials and Methods: 53 patients with adhesive capsulitis were included in the study and in all the patients a mixture of steroid and prolotherapy agent was injected into the coracohumeral ligament under the sonographic guidance. The patients were evaluated using the VAS and ROM of the shoulder before the injection and at 8 weeks and at 1 year after the injection. Results: Forward flexion was 93.4 degrees before the injection and was 142, 153 degrees at 8weeks and 1 year after injection. Abduction was 79.2 degrees before the injection and was 125.4, 152.6 degrees at 8 weeks and 1 year after the injection. The VAS score was 6.7 before the injection and was 3.5, 3.7 at 8 weeks and 1 year after the injection. Conclusion: The ultrasound guided injection of prolotherapy and steroid mixture into the coracohumeral ligament in patients with adhesive capsulitis is allowing both tissue distension and inflammatory process controlling procedure. It is effective in improving the range of shoulder motion significantly and is also effective in decreasing the pain.

• Journal of Chest Surgery
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• v.30 no.4
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• pp.373-377
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• 1997

Between January, 1991 and May 1995, mitral valve repair was undertaken on 32 patients under 15 years for congenital mitral regurgitation. Mean age was 24.0$\pm$26.1 months(range 3 months to 15 years), 16 patients were male and 16 patients were female associated cardiac anomalies were found in 26 patients (81%), and ventricular septal defects were noted in 18 patients(56%). In regards to pathologic findings, there were annular dilatation(n:7), leaflet prolapse(n=18), cleft leaflet(n=5) and restricted valve motion (n=2). The method of repair consisted of annuloplasty(Modif ed Devega type) in 14, repair of redundunt leaflet in 6, closure of cleft in 5, triangular resection in 2 and splitting of papillary muscle in one. There was no operative mortality and two late deaths occurred as a result of heart failure and sepsis. Tro patients required replacement of the mitral valve after 3 months and 7 months respectivehy because of recurrent mitral regurgitation. Actuarial survival was 92.5% at 46 months and actuarial freedom from reoperation was 95% at 12 months and 92.5% at 46 months. Actuarial freedom from valve repair failure was 68% at 12 months and 61.8% at 46 months. Although valve repair failure rate was high, we believe that mitral valve repair should be of rcrred to children because of low mortality and low reoperation rate.

• Science of Emotion and Sensibility
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• v.9 no.2
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• pp.133-140
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• 2006

In order to investigate the sensation of the fabric sound simulating the real wear-condition, the fabric sound simulator using reciprocating friction was developed. Fabric sounds from 5 specimen were generated by the fabric sound simulator and recorded using high performance microphone. Physical sound parameters of fabrics including level pressure of total sound (LPT), level range (${\Delta}L$), and frequency differences (${\Delta}f$) were calculated. For psychological evaluation, seven adjectives for sound (softness, loudness, sharpness, clearness, roughness, highness, and pleasantness) were used as the semantic differential scale. Fabric sounds by reciprocating friction of nylon taffeta and polyester leno had the highest value of LPT and evaluated as loud, sharp, rough, and unpleasant while polyester ultra suede and silk crepe de chine haying the lower LPT and ${\Delta}f$ were perceived as soft and quite. Comparing with fabric sound by one-way friction, fabric sound by reciprocation friction was perceived as more sharp, loud, and rough. LPT was also the most important factor affecting the sensation of the fabric sound by reciprocating friction.

• Clinics in Shoulder and Elbow
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• v.2 no.2
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• pp.157-169
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• 1999

Eighty-nine shoulders in eighty-eight patients with traumatic unilateral anterior shoulder instability were evaluated for Rowe and UCLA scores, recurrence, return to activity, and range of motion by an independent examiner at an average of 39 months after either arthroscopic or open Bankart repair using suture anchors. The arthroscopic technique included a minimum of 3 anchors, and a routine incorporation of capsular plication and proximal shift. Twenty­six shoulders(86.6%) out of thirty in the open Bankart repair group had excellent or good results while fifty­four(91.5%) of the fifty-nine shoulders with arthroscopic Bankart repair had excellent or good results. The arthroscopic group revealed significantly better results in the Rowe(p=.041) and UCLA scores(p=.026). Two shoulders in each group developed redislocation. There were no significant differences in the loss of external rotation and return to prior activity between the two groups(p>.05). The residual instability occurred more frequently in the group of patients with lesser anchors. Arthroscopic suture anchor capsulorraphy has results equal to or better than the open Bankart procedure.

• Korean Journal of Applied Biomechanics
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• v.19 no.2
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• pp.399-406
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• 2009

The purpose of this study was to compare the effect of wearing roller shoes and jogging shoes on kinematic characteristics in lower extremity during walking. Eight male middle school students(age: $15.0{\pm}0.0^{\circ}$ yrs, height $175.9{\pm}6.6cm$, weight: $616.3{\pm}84.9$ N) who have no musculoskeletal disorder were recruited as the subjects. Temporal parameters, step length, stride length, center of mass, velocity of CM, angle of segment, angular velocity and range of motion were determined for each trial. For each dependent variable, paired t-test was performed to test if significant difference existed between shoe conditions(p < .05). The results showed that stride length and velocity of CM in wearing roller shoes were significantly less than those found in wearing jogging shoes. These indicated that walking patterns may be changed by different shoe conditions and unstable braking condition because of wheel. Angle of ankle joint at LHC1 and LHC2 in wearing roller shoes was greater than the corresponding value for wearing jogging shoes. It seems that the ankle joints are locked in an awkward fashion at the heel contact to compensate for imbalance. Otherwise, dorsi flexion was not produced at the heel contact point in wearing roller shoes.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.1 no.2
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• pp.86-90
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• 2008

Purpose: To evaluate the differences between blindly and ultrasonography (US)-guided during multiple needling and dextrose injection technique for calcific tendinitis of shoulder. Materials and Methods: We chose 36 symptomatic calcific tendinitis patients, whose age ranged from 27 to 69. Our procedures were multiple needling and injection of dextrose over the lesion of calcific deposits. The bind injection group were 19 patients whose age ranged from 27 to 64-year-old (mean 52.2), and the US-guided injection group were 17 patients ranged from 31 to 69-year-old (mean 49.0). We compare these groups by VAS (visual analogue scale) and range of motion before and after procedures. Results: There is no difference between two groups in VAS and ROM before procedure (p>0.05). Two groups revealed significant improvement without limitation of shoulder function, however, the group under US-guided revealed better results than under blind (VAS:p=0.001, Flexion:p=0.000, Abduction:p=0.000, External rotation: p=0.016). Conclusion: Ultrasonography-guided procedure showed better results than blind, so the use of ultrasonography is more promising procedure.

• Clinics in Shoulder and Elbow
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• v.12 no.1
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• pp.7-13
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• 2009

Purpose: To evaluate the clinical and radiological results of arthroscopic tuberoplasty for irreparable massive rotator cuff tears. Materials and Methods: Eleven patients underwent arthroscopic tuberoplasty for irreparable massive rotator cuff tears between December 2004 and April 2007. The mean follow-up period was 17.3 months, and the average age at the time of surgery was 61.7-year-old. Five cases underwent arthroscopic tuberoplasty and 6 cases had arthroscopic subacromial decompression and tuberoplasty, simultaneously. Results: The average Constant score improved from 61.8 to 86.9 and the average UCLA score changed from 14.8 to 31.8 with 6 excellent, 3 good and 2 poor results (p=0.003). The active forward flexion improved from $111.8^{\circ}$ to $154.1^{\circ}$(p=0.011). The acromiohumeral interval increased from 3.94 mm preoperatively to 4.22 mm postoperatively (p=0.12). In the poor UCLA score group, the acromiohumeral interval changed from 1.67 mm preoperatively to 0.94 mm postoperatively. Conclusion: Arthroscopic tuberoplasty may be a second option to relieve the pain of irreparable massive rotator cuff tears and improve the range of motion. However, good results could not be expected if the acromiohumeral interval is < 2 mm preoperatively and decreased postoperatively.

• PNF and Movement
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• v.21 no.3
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• pp.345-356
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• 2023

Purpose: The aim of this study was to investigate the effects of physical therapy combined with a virtual reality (VR) game on pain, quality of life (QOL), engagement, and knee function in post-knee-surgery patients. Methods: Twenty-four patients who had undergone knee surgery four weeks or more before the study were recruited. Two withdrew from the study during the four-week experimental period, and a total of 22 patients were included in the final analysis. Routine physical therapy consisting of electrostimulation (10 min.) and therapeutic massage (10 min.) was the base intervention for all groups. The experimental group (n = 10) was additionally exposed to a VR game intervention, while the control group (n = 12) underwent an intervention involving similar motions as the experimental intervention but with no VR. The intervention for the experimental group used the game Rig Fit Adventure on Nintendo switch. Both groups underwent their respective interventions 3 times a week (35 min. per session) for 4 weeks. Pain was assessed using the numeric rating scale (NRS), and QOL was assessed using the EuroQol five-dimensional five-level questionnaire (EQ-5D-5L). Engagement was assessed using the Korea flow state scale (K-FSS). Finally, knee movement and function were assessed based on knee flexion and extension, range of motion (ROM), and Western Ontario and McMaster Universities Arthritis Index (WOMAC). Results: After the four-week physical therapy, both groups showed significant reductions in pain (on the NRS), increased knee ROM (flexion), better WOMAC scores, and increased EQ-5D-5L scores (p < 0.05), with the experimental group showing significantly better improvements in EQ-5D-5L and K-FSS scores (p < 0.05). Conclusion: The results of this study confirm that a VR-game-integrated intervention is effective for improving pain, QOL, engagement, and knee function in post-knee surgery patients and that VR-game-integrated interventions could be therapeutic alternatives for patients bedridden for prolonged periods with little motivation for rehabilitation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4676-4685
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• 2012

We investigated to compare the effects of a low intensity eccentric exercise and dynamic stretching on symptoms of delayed onset muscle soreness (DOMS). The eighteen women who had not participated in a regular exercise programme for the lower extremities in the previous five months were randomly assigned to one of three experimental groups: control group, a low intensity eccentric exercise group and dynamic stretching group. We measured the joint range of motion (ROM), maximal voluntary isometric exercise (MVIC), muscle soreness rating scale and ultrasound image measurement before eccentric exercise inducing DOMS, and 24, 48, and 72 hours after an eccentric exercise inducing DOMS. The exercise programme in a low intensity eccentric exercise group and dynamic stretching group were respectively performed 3 times a week for 4 weeks before eccentric exercise inducing DOMS. There was significantly different between the groups in muscle soreness rating scale and MVIC (p<.05). However, there was not significantly different between groups in ultrasound image measurement and ROM (p<.05). These results suggest that a low intensity eccentric exercise group and dynamic stretching group effectively reduced muscle soreness rating scale out of the symptoms of DOMS. A low intensity eccentric exercise group may be an effective improvement than dynamic stretching group in muscle soreness rating scale.