• Korean Journal of Optics and Photonics
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• v.33 no.6
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• pp.310-316
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• 2022

In this paper, the difference in modulation transfer function (MTF) results according to the change in the angle of a slant target when measuring a presampled MTF was confirmed, and the difference was reduced by fitting the edge spread function graph obtained to reduce the error by the target's rotation. Due to the feature of the presampled MTF method, the spatial frequency changed due to the sensor's projected intensity being changed by the target's rotation, and it was confirmed that the difference in the MTF value occurred depending on the rotation angle of the target. In this paper, the MTF was calculated after fitting only one column of the acquired image. It was confirmed that the rotation error is smaller compared to the case of the presampled MTF method and this fitting method can be applied to a scene that contains various target angles, such as auto-focusing using the MTF.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.409-410
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• 2012

• Korean Journal of Applied Biomechanics
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• v.18 no.2
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• pp.85-94
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• 2008

The purpose of this study is to provide basic materials for amateur golf players or golf maniacs to learn desirable iron swing motions. This study compared and analyzed the swing motions of iron clubs(3, 6, 9) by using 3-D in three elite golf players. 1. There was no a great difference in the total of swing time by club and the time by phase was nearly similar. 2. There was no a difference in the change in a head location at address and impact by club. 3. The angle change in a right knee joint was similar by club except the difference according to the length of the club. 4. There was a subtle difference in hip rotation angle by club. 5. In each club, the same rotation angle of shoulder joint at address and impact motions contributed to accurate swing, and the maintenance of more than $90^{\circ}$ of shoulder rotation angle in top swing increased swing rotation. 6. Although subtle, the forward angle of upper body was increased with a shorter club. $30-36^{\circ}$ of forward angle of upper body was maintained at address, top swing, and impact motions.

• The Journal of Korea Robotics Society
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• v.6 no.3
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• pp.247-254
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• 2011

This paper presents a method of sonar grid map matching for topological place recognition. The proposed method provides an effective rotation invariant grid map matching method. A template grid map is firstly extracted for reliable grid map matching by filtering noisy data in local grid map. Using the template grid map, the rotation invariant grid map matching is performed by Ring Projection Transformation. The rotation invariant grid map matching selects candidate locations which are regarded as representative point for each node. Then, the topological place recognition is achieved by calculating matching probability based on the candidate location. The matching probability is acquired by using both rotation invariant grid map matching and the matching of distance and angle vectors. The proposed method can provide a successful matching even under rotation changes between grid maps. Moreover, the matching probability gives a reliable result for topological place recognition. The performance of the proposed method is verified by experimental results in a real home environment.

• Journal of radiological science and technology
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• v.33 no.1
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• pp.19-24
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• 2010

The aim of this study was to evaluate the change of bone mineral density according to distal radius rotation and the correlations of the lowest BMD measured by DXA at the lumba versus distal radius. The eleven males were projected distal radius by DR X-ray and the measurement of BMD by DXA of the appropriate position of the forearm were performed on 21 males. The healthy 11 and 21 volunteers without any history of operations, anomalies, or trauma were enrolled. The experiment was performed by two methods. First, The DR X-ray was measured distal radius of 11 males in pronation and supination with three, six and nine degrees, including a neutral position. The ROI was measured by the m-view program on the PACS monitor. Second, The DXA was measured distal radius of 21 males in pronation and supination with five and ten degrees, including a neutral position to evaluate the changes of BMD according to the rotation. A correlation of the BMD in the distal radius with BMD that lumbar spine was performed, along with analysis of the data by SPSS 12.0v. The mean rotation angle of the distal radius about eleven males DR X-ray measured $7^{\circ}$ of pronation (82%, n = 9), $6^{\circ}$ of supination and $0^{\circ}$ of neutral of (9%, n = 1), The total average rotation angle in 11 male was $5.1^{\circ}$ of pronation. The rotation angle of the distal radius about twenty one males on DXA measured $7.2^{\circ}$ of pronation (43%, n = 9), $7^{\circ}$ of supination (24%, n = 5), and $0^{\circ}$ of neutral (33%, n = 7), The total average rotation angle in 21 people was $4.1^{\circ}$ of pronation. The correlation of the analysis of lumba and distal radius were r = 3.0, p = 0.18. consequently, The correlation was not significance. Because BMD of lumba was not coverd for BMD of the distal radius, with a neutral position, Pronation is needed for BMD in the distal radius with the rotation angle measuring at the lowest BMD. the rotation angle about five degrees of pronation of the distal radius is recommended.

• Journal of Information Processing Systems
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• v.16 no.1
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• pp.120-131
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• 2020

In order to solve the problem of point clouds coordinate conversion of non-directional scanners, this paper proposes a basic Rodrigues rotation method. Specifically, we convert the 6 degree-of-freedom (6-DOF) rotation and translation matrix into the uniaxial rotation matrix, and establish the equation of objective vector conversion based on the basic Rodrigues rotation scheme. We demonstrate the applicability of the new method by using a bar-shaped emboss point clouds as experimental input, the three-axis error and three-term error as validate indicators. The results suggest that the new method does not need linearization and is suitable for optional rotation angle. Meanwhile, the new method achieves the seamless splicing of point clouds. Furthermore, the coordinate conversion scheme proposed in this paper performs superiority by comparing with the iterative closest point (ICP) conversion method. Therefore, the basic Rodrigues rotation method is not only regarded as a suitable tool to achieve the conversion of point clouds, but also provides certain reference and guidance for similar projects.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.19 no.2
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• pp.1-9
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• 2013

Background: The purpose of this study is to analysis of correlation upper body according to forward head posture. Methods: The subjects of this study were 40 female university students who were equally and randomly allocated to a forward head posture group, normal group. Using general posture system, electromyograph, visual analogue scale, tape measurement, neck disability index were evaluated. Results: There was positive correlation between posture analysis and Sternocleidomastoid, neck flexion (p<.05). There was positive correlation between Craniovertebral angle (CVA) and trapezius upper, VAS (p<.05). There was negative correlation between posture analysis and CVA (p<.05). There was negative correlation between Cranial rotation angle and CVA (p<.05). Conclusion: Increased forward head posture lead to increase of pain, muscles activity, so it suggests to be necessary on the prevention of dysfunction and limited activities daily living.

• Journal of Broadcast Engineering
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• v.23 no.2
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• pp.235-245
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• 2018

Recently panoramic image overcomes camera limited viewing angle and offers wide viewing angle by stitching plenty of images. In this paper, we propose pre-processing and post-processing algorithm which makes speed and accuracy improvements when making panoramic images. In pre-processing, we can get camera sensor information and use three-dimensional rotation angle to find RoI(Region of Interest) image. Finding RoI images can reduce time when extracting feature point. In post-processing, we propose weighted minimal error boundary cut blending algorithm to improve accuracy. This paper explains our algorithm and shows experimental results comparing with existing algorithms.

• Journal of Korean Foot and Ankle Society
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• v.12 no.1
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• pp.1-8
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• 2008

Purpose: To evaluate the value and limitation of modified Mau osteotomy through the review of 30 feet treated by this procedure. Materials and Methods: We retrospectively analyzed 30 cases treated with modified Mau osteotomy since 2002. The mean duration of follow-up was 10 months. We reviewed medical records to describe each case and select several clinical factors which related with surgical procedure and could influence on final results. We measured radiographic parameters such as hallux valgus angle (HVA), intermetatarsal angle (IMA), distal metatarsal articular angle (DMAA), sesamoid position and also assessed clinical outcomes by AOFAS score and satisfaction degrees. Results: The mean preoperative HVA and IMA were $40.4^{\circ}$, $17.4^{\circ}$ and the mean amounts of correction were $31.2^{\circ}$ and $11.5^{\circ}$. Amounts of delayed loss of correction were 16.8% in HVA and 19.2% in IMA. Initial HVA, rotational angle and translation distance of the distal fragment, stability of fixation, first ray instability were revealed as significant factors for the final result from this procedure. DMAA was increased by rotation of the distal fragment and decreased by adding translation on the rotation. Conclusion: Modified Mau osteotomy is an effective procedure to get enough correction. But, it is important to try to avoid excessive rotation of the distal fragment because it may worse joint congruity. It may be worthwhile to pay close attention to the direction of saw and stability of fixation.

• Journal of Korea Multimedia Society
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• v.15 no.11
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• pp.1341-1348
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• 2012

In this paper, an efficient scheme for correcting rotated objects in medical images using the Mojette transform is presented. The Mojette transform is a kind of discrete Radon transform, where the transform domain is represented by a set of projections. The Mojette transform currently studied in the image compression area is modified for detecting the rotation angle of objects in medical images. First, in order to find accurate rotation angle, the projection value in the Mojette transform is determined by using pixels on the projection line and in addition the linear interpolation of pixels adjacent to the line. Second, at each projection angle, only one projection is implemented for reducing the amount of the calculation in the process of the Mojette transform. Finally, the projection in the Mojette transform is carried out at the predetermined ROI(Region Of Interest) at which the objects are not cropped or added by rotating the image. The simulation results show that the proposed method has good performance for correcting the rotation angle in medical images.