• The Journal of Korean Physical Therapy
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• 제13권1호
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• pp.115-125
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• 2001

The purpose of this study was to determine the relationship between rotation of the humerus and the shoulder movement in the sagital, coronal, and diagonal planes. Thirty normal subjects(15 male. 15 female)were tested using Cybex NORMTM Testing & Rehabilitation System (CYBEX Division of LUMEX, Inc., Ronkinkoma, New York). The subjects performed active shoulder flexion, abduction and PNF patterns. The range of motion(ROM) of the glenohumeral joint was measured three times. In order to assure the statistical significance of the results. the independent t-test. and a pearson's correlation were applied of the .05 and .01 level of significant. The results of this study were as follow ;1. There were statistically significant differences between shoulder flexion with humerus medial rotation and shoulder flexion with humerus lateral rotation(p <.01). 2. There were statistically significant differences between shoulder abduction with humerus medial rotation and shoulder abduction with humerus lateral rotation(p <.01). 3. There were statistically significant differences between PNF pattern(flex-abd-ext rot) with humerus medial rotation and PNF pattern with humerus lateral rotation(p < .01).For effective rehabilitation of the shoulder, physical therapists must have correct knowledge of shoulder movements. Physical therapists should consider these results when the goal of treatment is to increase ROM of the shoulder.

• The Korean Journal of Applied Statistics
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• 제17권1호
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• pp.61-73
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• 2004

Rotation sampling designs may be classified into two categories. The first type uses the same sample unit for the entire life of the survey. The second type uses the sample unit only for a fixed number of times. In both type of designs, the entire sample is partitioned into a finite number(=G) of rotation groups. This paper is generalization of the first type designs. Since the generalized design can be identified by only G rotation groups and recall level 1, we denote this rotation system as l/G rotation design. Under l/G rotation design, variance and mean squared error (MSE) of generalized composite estimator are derived, incorporating two type of biases and exponentially decaying correlation pattern. Compromising MSE's of some selected l/G designs, we investigate design efficiency, design gap effect, ans the effects of correlation and bias.

• Clinics in Shoulder and Elbow
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• 제18권1호
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• pp.13-20
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• 2015

Background: The purpose of this study is to assess the range of shoulder motion using an indirect evaluation method without physical examinations of patients based on questionnaires regarding several specific arm postures referenced by patient's own body parts. Methods: Nine criteria of specific shoulder motion including 4 forward flexion, 2 external rotation, and 3 internal rotation were decided as reference position which can represent a certain shoulder motion. Flexion contains postures such as lifting arm to waist-height, shoulder-height, eye-height, and raising arm above head with arm touching ears. External rotation comprises grasping ears and placing hands on back of the head. Vertebral height in internal rotation is determined by calculating the samples' motions, which are holding on to trouser belts, opposite-elbow, and scapula. These postures are included in questionnaires for patients to evaluate the validity and effectiveness of this indirect method. Results: The range of flexion was $77^{\circ}$ ($60^{\circ}$ to $100^{\circ}$), $96^{\circ}$ ($87^{\circ}$ to $115^{\circ}$), $135^{\circ}$ ($115^{\circ}$ to $150^{\circ}$), and $167^{\circ}$ ($150^{\circ}$ to $175^{\circ}$) when arms go up to waist, shoulder, eye, and high vertically. Range of external rotation was $39.6^{\circ}$ ($30^{\circ}$ to $50^{\circ}$) when grasping ears and $69.2^{\circ}$ ($60^{\circ}$ to $80^{\circ}$) with the hands on the back of the head. Range of internal rotation was L4 when placing trouser belts, T12 for holding opposite elbow, and T9 for reaching scapula. The mismatch rates of flexion, external rotation, and internal rotation were 11.6%, 9.6%, and 7.8%. Conclusions: The range of shoulder motion using this method is expected to be applied to an established shoulder scoring system which included shoulder motion evaluation item.

• Physical Therapy Korea
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• 제13권1호
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• pp.24-31
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• 2006

The purpose of this study was to identify the effect of the hip internal rotation on gluteal and erector spinae muscle electromyographic (EMG) activity during treadmill walking. Eleven healthy subjects were recruited. All subjects performed treadmill walking while maintaining the hip in neutral position (condition 1) and in internal rotation (condition 2). Surface EMG activity was recorded from four muscles (gluteus maximus (GM), gluteus medius (GMED), tensor fascia latae (TFL), and erector spinae (ES)) and the hip internal rotation angle was measured using a three dimensional motion analysis system. The gait cycle was determined with two foot switches, and stance phase was normalized as 100% stance phase (SP) for each condition using the MatLab 7.0 program. The normalized EMG activities according to the hip rotation (neutral or internal rotation) were compared using a paired t-test. During the entire SP of treadmill walking, the EMG activities of GM in condition 1 were significantly greater than in condition 2 (p<.05). The EMG activities of TFL and ES in condition 2 were significantly greater than in condition 1 (p<.05). The EMG activities of the GMED in condition 1 were significantly greater than in condition 1 (p>.05) except for 80~100% SP. Further studies need randomized control trials regarding the effect of hip internal rotation on the hip and lumbar spine muscle activity. Kinetic variables during gait or going up and down stairs are also needed.

• Journal of the Korean Society of Physical Medicine
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• 제14권3호
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• pp.39-45
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• 2019

PURPOSE: We investigated the most effective way to activate the posterior oblique sling muscles by performing prone hip extension exercises. METHODS: An electromyography system was used to measure the activation of the posterior oblique sling muscles (latissimus dorsi, gluteus maximus, multifidus, and biceps femoris) in three different prone hip extension exercises of in 12 healthy individuals (6 men and 6 women): 1) prone hip extension, 2) prone hip extension with internal rotation and extension of the arm, and 3) prone hip extension with internal rotation and extension of the arm with a 1-Ib dumbbell. RESULTS: The overall muscular activation of the posterior oblique sling muscles was more increased when performing 1) prone hip extension with internal rotation and 2) prone hip extension with internal rotation and extension of the arm with a 1-Ib dumbbell as compared with that during prone hip extension except for the biceps femoris activation. There was a statistically significant difference in the activities of the contralateral multifidi among all three exercises; of the ipsilateral multifidi in PHE1) prone hip extension alone, PHE2) prone hip extension with internal rotation and extension of the arm and PHE3) prone hip extension with internal rotation and extension of the arm with 1-Ib dumbbell; and of the ipsilateral gluteus maximus among all the prone hip extension exercises. There was no significant difference in the activity of the biceps femoris among the three exercises. CONCLUSION: Prone hip extension with internal rotation and with internal rotation and extension of the arm with 1-Ib dumbbell can activate the posterior oblique sling muscles and so prevent back pain in healthy people.

• Journal of the Korea Institute of Military Science and Technology
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• 제4권2호
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• pp.147-156
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• 2001

In this paper, a robust attitude control scheme based on Eigenaxis rotation for the spacecraft is proposed. Eigenaxis rotation transforms the attitude of spacecraft to the shortest path and is represented by quaternion. The control law consists of PD-type control part for the nominal system and the robust control part for compensating inertia uncertainty. For the proposed controller, stability analysis is performed and the performance is shown via computer simulation.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제38A권3호
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• pp.224-239
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• 2013

An exact performance analysis of an ML detector for a 2-dimensional rotation-transform aided QPSK system operating over an impulsive noise environment is presented using Rieman integrals of a two-dimensional Gaussian Q-function over Voronoi cells. A set of interesting features of the Voronoi cells is also characterised systematically. An optimum rotation angle yielding the minimum BER is also studied. The differences between the proposed exact method and the previous approximate analysis method are investigated in terms of the corresponding BERs and the derived optimum angles.

• Korean Journal of Applied Biomechanics
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• 제27권1호
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• pp.67-74
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• 2017

Objective: The purpose of this study was to apply a general linear model in statistics to marker position vectors used to study human joint rotational motion in biomechanics. Method: For this purpose, a linear model that represents the effect of the center of hip joint rotation and the rotation of the marker position on the response was formulated. Five male subjects performed hip joint functional motions, and the positions of nine markers attached on the thigh with respect to the pelvic coordinate system were acquired at the same time. With the nine marker positions, the center of hip joint rotation and marker positions on the thigh were estimated as parameters in the general linear model. Results: After examining the fitted model, this model did not fit the data appropriately. Conclusion: A refined model is required to take into account specific characteristics of longitudinal data and other covariates such as soft tissue artefacts.

• Journal of Institute of Control, Robotics and Systems
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• 제12권8호
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• pp.798-804
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• 2006

To overcome the limited relative uncertainty and work range of the existing planar stage and the bulk structure of the contact-less motor for rotation, the novel operating principle to realize the precise rotation is suggested. It uses the two-axial vector forces, normal force and thrust force, of three-induction type of axial motors located $120^{\circ}$ apart, resulting in the contact-free rotation of the mover. Firstly in this paper, the magnetic forces across the air gap are modeled and simulated under the various conditions. It clarifies the feasible range of the derived solution. And the algorithm compensating the strong cross couple between the forces and the control inputs; generally AC magnitude and slip frequency, is given to realize the independent control of six axes. Finally, for the successfully implemented system, the round test and the micro step test results are given.

• Journal of Institute of Control, Robotics and Systems
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• 제9권7호
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• pp.556-562
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• 2003

This paper presents new attitude error differential equations to define attitude errors as the rotation vector for inertial navigation systems. Attitude errors are defined with the rotation vector between the reference coordinate frame and the platform coordinate frame, and Platform dynamics to the reference coordinate frame due to platform torque command errors are defined. Using these concepts for attitude error definition and platform dynamics, we have derived attitude error differential equations expressed in original nonlinear form for GINS and SDINS and showed that these are equivalent to attitude error differential equations expressed in known linear form. The relation between attitude errors defined by the rotation vector and attitude errors defined by quaternion is clearly presented as well.