• The Journal of Korean Physical Therapy
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• v.31 no.2
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• pp.76-81
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• 2019

Purpose: This study examined the effects of squatting with different foot positions on the muscle activation of the vastus medialis oblique (VMO) and vastus lateralis (VL) muscles in subjects with genu varum. Methods: Thirty four subjects participated in this study. Surface electromyography was used to measure the muscle activation of the VMO and VL muscles at the knee angles ($15^{\circ}$, $60^{\circ}$) at three foot positions (internal rotation, neutral position, external rotation) during squatting. Results: Muscle activation differences at different knee angles and foot positions differed significantly between the VMO and VL muscles in both the varus and normal groups. In addition, there was a significant difference according to the knee angles with the foot in external rotation in the VMO and VL ratio. In the varus group, however, the VMO and VL ratio were significantly different only with the feet in internal rotation. In the muscle activation changes of the knee angle differences in the foot position, there was no significant difference in the varus group, but both the VMO and VL muscles were significant different in the normal group. Conclusion: In both groups, regardless of the foot position, muscle activation of the VMO and VL muscles increased with increasing knee flexion angle. In the normal group, when squatting with the feet in external rotation, the VMO and VL muscles activations increased with increasing knee angle. In the varus group, however, the foot position did not affect the VMO or VL muscle activation. This study shows that subjects with genu varum and normal subjects have different VMO and VL muscle activation patterns during squat exercises.

• Journal of the Korean Society of Physical Medicine
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• v.11 no.3
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• pp.119-124
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• 2016

PURPOSE: The aim of this study was to evaluate activation of accessory respiratory muscles using electromyography during chest expansion upper extremity flexion, abduction, and external rotation exercises with an elastic band in children with cerebral palsy. METHODS: The subjects were 10 children with cerebral palsy. The inclusion criterion for participation was a Gross Motor Function Classification System level of I to III. The subjects were instructed to perform upper extremity flexion, abduction, and external rotation exercises with inspiration, and extension, adduction, and internal rotation exercises with expiration while seated on a chair without a backrest. PM (Pectoralis major), SCM (sternocleidomastoid), RA (rectus abdominis), and EO (external oblique) muscle activities were measured using electromyography. RESULTS: All tested muscles showed a statistically significant increase in activity after elastic band exercise. There were significant differences in PM, SCM, RA, and EO results after chest expansion exercise using elastic band. SCM showed the largest increase in activity after use of elastic bands, at $52.37{\pm}45.88$%, followed by the RA ($50.56{\pm}79.31$), EO ($35.42{\pm}35.45$), and PM ($31.72{\pm}25.64$). The increase in the SCM was greatest, followed by increases in the RA, EO, and PM CONCLUSION: These finding suggest that activity of accessory respiratory muscles increases with use of elastic bands during chest expansion exercise in cerebral palsy.

• Clinics in Shoulder and Elbow
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• v.7 no.2
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• pp.70-75
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• 2004

Purpose: To evaluate the results of arthroscopic repair of traumatic anterior shoulder instability with glenoid bone defect. Materials and Methods: Nineteen patients who had underwent arthroscopic repair for the shoulder with traumatic anterior instability and glenoid bone defect were retrospectively reviewed. Mean age was 24.6 years(range, 20 to 39) and mean follow-up was 23 months(range, 19 to 55). No glenoid bone defect was greater than 7mm in length and 20% of the glenoid. The results were evaluated according to stability, range of motion and function. Results: All patients obtained excellent-good results according to Rowe scoring system. Two patients(10.5%) had instability. The mean loss of external rotation was 15 degrees (range, 0 to 25). Functionally, 17 patients could participate in preinjured work or sports to the same level with or without mild discomfort. The remained 2 patients who had 25 degree loss of external rotation could not play sports. Conclusion: Though arthroscopic repair is a good treatment for traumatic anterior shoulder instability with small glenoid bone defect, it is possible to cause loss of external rotation

• Korean Journal of Applied Biomechanics
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• v.26 no.3
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• pp.257-264
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• 2016

Objective: The purpose of this study was to determine the periodicity of shank-foot segment coupling and free torque before and after fatigue induced by prolonged running. Method: Fifteen young healthy male participants with a rear-foot strike ran on instrumented dual-belt treadmills at 70% of their maximum oxygen uptake for 65 min. Kinematic and ground reaction force data were collected for 20 continuous strides at 5 and 65 min (considered the fatigued condition). The approximate entropy tool was applied to assess the periodicity of the shank internal-external rotation, foot inversion-eversion, shank-foot segment coupling, and free torque for the two running conditions. Results: The periodicity of all studied parameters, except foot inversion-eversion, decreased after 65 min of running (fatigued condition) for 80% of the participants in this study. Furthermore, 60% of the participants showed similarities in the change of periodicity pattern in shank internal-external rotation, coupling, and free torque. Conclusion: The findings indicated that the foot inversion-eversion motion may pose a higher risk of injury than the shank internal-external rotation, coupling, and free torque in the fatigued condition during prolonged running.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.74.3-75
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• 2019

Recent Integral Field Spectroscopy (IFS) studies revealed that not only late type galaxies (LTGs) but also early type galaxies (ETGs) have various kinds of kinematic rotation. (e.g. not clearly detectable rotation, disk-like rotation, kinematically distinct core (Cappellari 06)) Among the various studies about galactic kinematics, one of the most notable anomalies is the star-gas misalignment. The gas forms stars and stars release gas through mass-loss. In this process, their angular momentum is conserved. Therefore, kinematic decoupling between stars and gas can occur due to external gas inflow or perturbation of components. There are some possible origins of misalignment: cold gas from filaments, hot gas from outer halo, interaction or merging events with galaxies and environmental effects. Misalignment, the black box from mixture of internal and external gas, can be an important keyword for understanding further about galaxies' kinematics and external processes. Using both SAMI IFS data(Sydney-AAO Multi-object Integral field spectrograph Galaxy Survey, Croom+12) and Horizon-AGN simulation(Dubois+14), we examined misaligned galaxies properties and distribution. Because the simulation has lots of galaxies at various z, we were able to study history of formation, evolution and extinction of misalignment, which was hard to be done with observation only.

• The Journal of Korean Physical Therapy
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• v.31 no.2
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• pp.134-139
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• 2019

Purpose: This study examined the most effective exercise while performing shoulder abduction below ninety degrees. Methods: Thirty two healthy individuals (17 males, 15 females) participated and performed four exercises, 1) Posterior fly, 2) Prone row, 3) Modified prone cobra, and 4) External rotation in the prone position. Surface electromyography (sEMG) was used to measure the electrical activities for the lower, middle and upper fiber of trapezius and serratus anterior. Results: A significant difference in the muscle activities of the upper/middle/lower trapezius and serratus anterior was observed among the three different positions in terms of the PF (posterior fly), PR (prone row), and MPC (modified prone cobra) (p<0.05). In post-hoc analysis, the activities of the lower and upper trapezius were significantly higher than those of the upper trapezius and serratus anterior (p<0.05). In addition, in ERP (external rotation in prone), there was a significant difference in each activity of the muscles. Post-hoc results indicated that the upper trapezius showed greater EMG activity than the other three muscles. Conclusion: External rotation in the prone position revealed the highest activation of the lower trapezius compared to upper trapezius muscle activity. This may be particularly useful in isolating the lower trapezius in cases where excessive scapular elevation is noted. Therefore, the most effective lower trapezius exercise should be performed below ninety degrees of shoulder abduction.

• Archives of Plastic Surgery
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• v.48 no.2
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• pp.158-164
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• 2021

Background In lower lateral cartilage (LLC) surgery, cephalic trimming poses risks for the collapse of the internal and external nasal valves, pinched nose, and drooping deformity. The cephalic lateral crural advancement (CLCA) technique presented herein was aimed at using a flap to increase nasal tip rotation and support the lateral crus, in addition to the internal and external nasal valves, by avoiding grafts without performing excision. Methods This study included 32 patients (18 female and 14 male) and the follow-up period for patients having undergone primer open rhinoplasty was 12 months. The LLC was elevated from the vestibular skin using the CLCA flap. A cephalic incision was performed without cephalic trimming. Two independent flaps were formed while preserving the scroll ligament complex. The CLCA flap was advanced onto the lower lateral crus while leaving the scroll area intact. The obtained data were analyzed retrospectively. Results The mean age of the patients was 31.6 years (range, 20-51 years). The Rhinoplasty Outcome Examination scores after 12 months varied from 90 to100 points, and 93% of patients reported perfect satisfaction. At a 1-year follow-up, the patients' nasal patency (visual analogue scale) rose from 4.56±1.53 (out of 10) to 9.0±0.65 (P<0.001). Conclusions The CLCA flap led to better nasal tip definition by protecting the scroll area, increasing tip rotation, and supporting the internal and external nasal valves without cephalic excision.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.81-81
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• 2000

We use camera to apply human vision system in measurement. To do that, we need to know about camera parameters. The camera parameters are consisted of internal parameters and external parameters. we can fix scale factor&focal length in internal parameters, we can acquire external parameters. And we want to use these parameters in automatically driven vehicle by using camera. When we observe an camera parameters in respect with that the external parameters are important parameters. We can acquire external parameter as fixing focal length&scale factor. To get lane coordinate in image, we propose a lane detection filter. After searching lanes, we can seek vanishing point. And then y-axis seek y-sxis rotation component(${\beta}$). By using these parameter, we can find x-axis translation component(Xo). Before we make stepping motor rotate to be y-axis rotation component(${\beta}$), '0', we estimate image coordinates of lane at (t+1). Using this point, we apply this system to Kalman filter. And then we calculate to new parameters whick make minimum error.

• Korean Journal of Applied Biomechanics
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• v.15 no.1
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• pp.207-219
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• 2005

The purpose of this study was to determine the effect of the foot rotation on the lower limb muscles. Fourteen subjects performed step-up/step-down at a cadence of 80 beats/min, exercises with the foot neutral, $35^{\circ}$ internally rotated, and $35^{\circ}$ externally rotated, respectively. For each variable, a one-way analysis of variance (ANOVA) was used to determine whether there were significant differences between genders and among the eight types of jump. When a significant difference was found in jump type, post hoc analyses were performed using the Tukey procedure. A confidence level of p < .05 was used to determine statistical significance. The results showed that significant changes in averaged IEMG values occurred with the internal rotation of the foot in the lateral gastrocnemius during the knee extension, and in the semitendinosus during the knee flexion. During the knee extension, however, the internal rotation of the foot produced a significantly lower Averaged IEMG values than the neutral foot position in the medial gastrocnemius. The results also found that the peak IEMG activity of the rectus femoris during the knee extension for the external rotation of the foot was Significantly higher than the corresponding values in the neutral position of the foot, while the intenal rotaion of the foot exhibited a significant difference with the neutral position of the foot in the semitendinosus during the knee flexion. In general, the foot rotation position did not influence the average IEMG and Peak IEMG values of most muscles. The practice of adopting foot rotation to selectively strengthen individual muscles of the lower limb was not supported by this study. The external rotation of the foot produced high muscle activities in the quadriceps during the knee extension. For the knee extension, therefore, maintaining a laterally rotated position should be need for stable and comfortable position.

• Korean Journal of Applied Biomechanics
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• v.24 no.3
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• pp.239-248
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• 2014

The purpose of this study was to quantify kinematic and kinetic characteristics of Yin-yang Bo gait according to their motor expertise, one of the Seokmun Ilwol martial art gait patterns. Yin-yang Bo gait pattern shows initial forefoot contact instead of heel contact, and increased time of stance phase time, internal-external rotation of ankle-knee-hip joints and pelvic. It aims to produce and store the more energy through continuous homeostasis of center of gravity (COG) and performance of stretch-shortening cycle. Some of these characteristics also were similar to the gait modification strategies for reducing knee adduction moment such as toe-out progression, medial thrust, internal rotation of hip joint. To identify the characteristics, four factors of expert Yin-yang Bo gait performance group were compared to that of none expert group; 1) angles of COG displacement and rotation 2) distal joint pre-rotation in internal-external rotation of ankle-knee-hip joints and pelvic, 3) invariability pelvic potential and pelvic segment total energy 4) knee abduction moment. Six healthy(three male) subjects participated in the experiment to perform Yin-yang gait pattern. Three-dimensional and force plate data were collected. Kinematic and kinetic data were compared between two groups using t-tests. Results showed that 1) the peak point of COG internal rotation angle was reduced in expert group, 2) kneeexternal and hip joint -internal and pelvic rotation angle peak frames were more near points in expert group.