• 대한정형도수물리치료학회지
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• 제18권2호
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• pp.41-47
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• 2012

Background: This study was designed to investigate the correlation between electromyography (EMG) activities in the vastus medialis oblique (VMO) vs vastus lateralis (VL) activity ratio and the valgus collapse knee position while stepping down. Methods: Twenty healthy women volunteered to participate in this study. We measured the frontal-plane projections of the knee valgus angle, knee valgus distance, and hip adduction angle by using a digital camcorder. After 3 repetitions of the step down (dominant side) exercise, the findings of the static and dynamic phases were analyzed. EMG activities data of the VMO:VL activity ratio were recorded during the step down exercise and were normalized to the maximal voluntary isometric contraction (MVIC) of the quadriceps. A paired t-test was used to compare the findings of the static and dynamic phases. We analyzed the Spearman's rank order correlation coefficient between the and VMO:VL ratio. Results: Hip adduction angle, knee valgus angle, VMO activity, VL activity, VMO:VL activity ratio were statistically higher in the dynamic phase than in the static phase (p<.05). Frontal-plane projections of knee valgus angle were significantly correlated with hip adduction angle (r=.459, p<.05) and knee valgus distance (r=.505, p<.05). However, the EMG activity ratio of the VMO and the VL did not show a significant change during step down exercise with respect to hip adduction angle (p=.875), knee valgus angle (p=.618), and knee valgus distance (p=.701). Conclusion: The results from this study indicate that frontal-plane projections of knee valgus angle were associated with hip adduction angle and knee valgus distance. On the basis of these results, the knee valgus distance may be used to determine the valgus collapse knee position while stepping down.

• 대한가정학회지
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• 제28권1호
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• pp.1-7
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• 1990

This study was carried out to investigate the influence of the various physiological function caused by girdle wearing. The four experimental methods used in this study are as follows. For example, the Reentgen photographing, body measurement by Sliding Gauge, mensurement of the electrocardiogram, measurement of the pulse and the blood pressure. The results of the investigation were as follows; 1. In the change of the various organs by Roentgen photographing, the diaphragm rised a little than normal position. The heart and stomach inclined to right side and the shape of stomach and duodenum are longer than the length of normal shape. Especially the phlorus of stomach was pressured strongly. 2. In the experimental change by the Sliding gauge and body measurement, the waist, hip and theigh girth of wearing-girdle reduced than at the no-girdle. The protruson of abdomen and hip section of wearing-girdle and the phenomenon of Hip-Up showed. 3. The difference by measurement of the electrocardiogram wasn't showed. The pulse of the wearing-girdle was increased slightly than the no-girdle. 4. The blood pressure of the wearing-girdle decreased slightly than the no-girdle.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.1071-1074
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• 1999

In this paper, we studied a computer based three dimensional implantation system of artificial hip joint. The system can be utilized for doctors to select a suitable artificial femur which is best-fit for the patient and to find out the optimal implanting position as well. We proposed a new numerical index to measure the fitness between the artificial hip joint and the patient's femur. The proposed fitness index accounts for the variance of the distance between the outer contours of artificial hip joint and the femur in addition to the conventional area comparison. A few simulation are run to show results of fitness measurement and compared to the conventional method.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2010년도 춘계 종합학술대회 논문집
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• pp.161-163
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• 2010

본 연구의 목적은 등속성 운동수행 및 측정시 hip joint angle에 따라 대퇴근육의 concentric 과 eccentric 근력차이를 분석하기 위하여 등속성 기기 의자 등받이 경사각도를 $100^{\circ}$, $120^{\circ}$, $140^{\circ}$에서 peak torque를 검사하였다. 대상자는 20대 초반의 건강한 남자 대학생 12명을 대상으로, 등속성 기기(Isomed 2000, Germany)를 이용하여 seated position에서 $60^{\circ}/s$ 의 각속도를 사용하여 검사를 수행하였다. 측정순서는 등속성기기 의자 등받이 경사각도 $100^{\circ}$, $120^{\circ}$, $140^{\circ}$ 순으로 2-3일 간격으로 진행하였다. 통계처리 방법은 SPSS 12.0 프로그램을 이용하여 평균과 표준편차를 산출하였으며, 각각의 hip angle에 따른 단축성과 신장성 peak torque 값의 차이는 one-way ANOVA(3RM)을 이용하여 처리하였고, 사후검증은 Tukey를 사용하였으며, 유의수준은 p<.05로 하였다. 연구결과 대퇴사두근의 단축성 근력은 등속성 기기 의자 등받이 경사각 $100^{\circ}$, $120^{\circ}$, $140^{\circ}$사이에 유의한 차이(p=.000)가 나타나 사후 분석결과 $100^{\circ}$와 $120^{\circ}$ 사이(p<.01) 그리고 $100^{\circ}$와 $140^{\circ}$ 사이(p<.001)에 유의한 차이를 나타내었으며, 신장성 근력에서는 유의한 차이가 나타나지 않았다. 햄스트링의 단축성 근력은 3종류의 hip angle사이에 유의한 차이(p=.001)가 나타나 사후분석결과 $100^{\circ}$와 $140^{\circ}$사이(p<.05) 그리고 $120^{\circ}$와 $140^{\circ}$ 사이(p<.01)에 유의한 차이를 나타내었으며, 그러나 신장성 근력에서는 유의한 차이가 나타지 않았다. 이러한 결과로 미루어 볼 때 등속성 운동수행 및 근력측정 시 hip joint angle 에 따라 대퇴사두근과 햄스트링의 단축성 근력에서 유의한 차이가 나타나 hip joint angle을 고려하여 대퇴근육의 운동및 측정이 이루어져야 할 것으로 사료된다.

• 한국운동역학회지
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• 제25권3호
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• pp.293-300
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• 2015

Objective : The purpose of this study was to compare the kinematic data of the horizontal rotation movements of shoulder, hip, knee during two-handed backhand drive stroke according to two different ball directions. Methods : The kinematic variables were analyzed such as the joint angles of the lower body, horizontal rotation angles of the shoulder, hip, inter-knee segment, body twist angle and difference in angle of forward swing. Two-handed backhand drive stroke was analyzed through a three-dimensional motion analysis. The collected data were analyzed by a paired t-test, and the statistical significant value was set at ${\alpha}=.05$. Results : The findings of this study were as follows; First, there was no difference in the total angles of lower limb joints from the forward swing position to impact posterior. Second, there was no difference in the horizontal rotation angles of E1 shoulder, hip, and E2 shoulder but the horizontal rotation angles of E1 knee, E2 hip, knee, E3, and E4 shoulder, hip, and knee were different in all events. Third, there was no difference in the body twist angle of the maximum horizontal rotation. In addition, there was no difference in the angle of the body twist by the ball direction in the shoulder-hip, the hip-knee and the shoulder-knee. Conclusion : Horizontal rotation angle determines ball directions.

• 한국운동역학회지
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• 제17권1호
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• pp.29-39
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• 2007

This study were obtained elapsed time phase-by-phases, displacement, user angle, velocity and angular velocity to analyse kinematically contributing factors at impact of forehand drive motion, on targeting three male players. The results of the study were presented as follows; In the forehand drive swing, the elapsed time by phases was a total of .52 seconds: .30 seconds from backswing to impact and .22 seconds from impact to follow-through, Considering the mean change in locations of COM of each(part$\rightarrow$body segment) at impact, racket head, left shoulder, right wrist and left hip, the left-right directions(X-axis) were showm to be each $.61{\pm}.03$, $1.19{\pm}.08$, $.66{\pm}.03$, $.94{\pm}.06$, and $.45{\pm}.03m$. The displacement differences of COM of each body segment were shown to be -.57, -.05, -.33, and .16m. For the vertical direction(Z-axis), the center of mass was lowest at impact and highest at E3. For the displacement of the right wrist on the left hip, the right wrist moved to .82m to the lower direction without change in the locations of the hip from E1 from E2. When the left hip moved .02m from E2 to E3, the right wrist moved .7m in the upper direction. In respect to the velocity of each body segment, the hip and the shoulder joint accelerated and then the wrist followed. Then the right wrists of all the subjects and their racket heads showed maximum speed, and an effective swing was observed. At the angle of each part, the angle of the right wrist was the smallest at the backswing and the largest at the moment of the impact. Then it increased gradually in the follow-through section. In respect of angular velocity for subject A, the hip moved and the largest change occurred. Immediately before the impact, the subject made a swing using his right wrist, his hip, and the shoulder joint, showing the maximum value, which was judged to be effective.

• 복식문화연구
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• 제19권4호
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• pp.820-835
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• 2011

The purpose of this study is to provide a basic pattern to assist in the development of formal pants that reflect the physical characteristics of women with lower-body obesity. The subjects selected for this study were women in their 20s and 30s with a Rohrer index of 1.6 or higher, a waist circumference 78.5cm to 83.5cm, and a lower drop of at least 18cm. The experimental pants patterns were developed by varying the waist line position, the waist ease, the ease in the hip area, the crotch length, the front and rear crotch width, the leg width, and the total length. Data analysis was performed using the SPSS statistics program(version 18.0). To verify the difference, this study used a variance analysis and Duncan's test. The conclusions drawn by the study are as follows. To reflect the form element of an abdomen with fatty deposits, the waist circumference should have an ease of 2cm. The front waist result was W/4+0.5cm+0.75cm and the rear waist result was W/4-0.5cm+0.25cm. The hip circumference showed a total ease of 4.5cm. The front hip result was H/4+0.75cm and the rear hip result was H/4+1.5cm. The crotch width set to H/16-1cm and the applied rear crotch width was H/16+2cm. The rear hip area was given more ease to reflect the protrusion of the hip. Along the line extending from the knee area to the crotch line, the outer seam line was designed with a gradual S-shaped curve to accommodate the protrusion from the maximum thigh width.

• 한국운동역학회지
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• 제22권3호
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• pp.295-304
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• 2012

This study, through biomechanical analysis, conducts a risk assessment of injury occurrence in ballet dancers while they perform running and jumping movements. The participants were nine female collegiate students majoring in ballet(age: $20.89{\pm}1.17years$; height: $160.89{\pm}7.01cm$; mass: $48.89{\pm}3.26$). Descriptive data were expressed as $mean{\pm}standard$ deviation(SD) for all variables. An independent t-test was conducted to determine how the following variables differed: duration time, position of the center of gravity, angle of the hip, torque of the hip, and muscle activity. All comparisons were made at the p<0.05 significance level. The results show that the jump time was two times longer than the run time in the duration time. The jump length was also longer than the run. The angle of the hip and the torque at the hip were higher in the right. The vastus medialis muscle was most frequently used. These findings demonstrate that participants' jumps may require more biomechanical variables for performance of better and more correct $jet{\acute{e}}$.

• 한국운동역학회지
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• 제20권3호
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• pp.311-318
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• 2010

This study examined the double piked dismount among the landing techniques of parallel bars based on three-dimensional motion analysis. Four male national gymnasts were the subjects. This study was performed to provide quantitative data highlighting players strengths and weaknesses to enable more stable landing technique. The variables analyzed were the position and velocity of center of gravity(CG) and angles of shoulder joints, hip joints, and trunk. The results are as follows: S1 secured the height of flight with fast vertical rise. After the easy spin in the air, he conducted a stable landing maintaining a proper hip joints angle. S2, S3, and S4, however, began the backward somersault already before leaving the bars, so they moved backward greatly making it more difficult to achieve a higher flight path. As a result, they couldn't control the velocity of their backward movement at landing. For a stable landing, they have to maintain the negative shoulder angle when rising, minimize both antero-posterioror side-to-side movements by doing a strong tap using hip joints, to secure the height of flight before the somersault. Results also show that at the descent, they should conduct rapid spinning by increasing their shoulder and hip joints to the maximum while controlling their velocity.

• 한국운동역학회지
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• 제28권2호
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• pp.127-134
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• 2018

Objective: In a statistical linear model estimating the center of rotation of a human hip joint, which is the parameter related to the mean of response vectors, assumptions of homoscedasticity and independence of position vectors measured repeatedly over time in the model result in an inefficient parameter. We, therefore, should take into account the variance-covariance structure of longitudinal responses. The purpose of this study was to estimate the efficient center of rotation vector of the hip joint by using covariance pattern models. Method: The covariance pattern models are used to model various kinds of covariance matrices of error vectors to take into account longitudinal data. The data acquired from functional motions to estimate hip joint center were applied to the models. Results: The results showed that the data were better fitted using various covariance pattern models than the general linear model assuming homoscedasticity and independence. Conclusion: The estimated joint centers of the covariance pattern models showed slight differences from those of the general linear model. The estimated standard errors of the joint center for covariance pattern models showed a large difference with those of the general linear model.