• Title/Summary/Keyword: Rotation correction

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Clinical Experience in Marginal Rotation (안검연외전술의 임상경험)

  • Chung, Wha-Sun;Kim, Chae-Ju;Cha, Soon-Cheol
    • Journal of Yeungnam Medical Science
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    • v.9 no.1
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    • pp.23-28
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    • 1992
  • Fifty-four marginal rotation procedures for cicatrical entropion and marginal entropion were performed in twenty-eight patients(8 males, 20 females). The age ranged from 4 to 74 years old(mean 51.1 years old). After the follow up periods of 6 to 48 months, excellent correction of the eyelid margin and good cosmetic appearance were noticed in most cases, but nine cases combined with severe trichiasis showed recurred trichiasis requiring reoperation.

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Digital fabrication and application of clear aligner after alignment with NiTi archwires (NiTi 호선을 이용한 초기 배열 후 디지털 방식 투명교정장치의 적용)

  • Lim, Sung-Hoon
    • The Journal of the Korean dental association
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    • v.54 no.7
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    • pp.551-562
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    • 2016
  • There are interferences between the teeth to be moved and the clear aligner made from setup. These interferences generate forces which move teeth to the desired position. However, these can cause incomplete tooth capture of clear aligner. When these interferences exceed the acceptable deformation of aligner, unwanted intrusion of teeth to be moved occurs. When correction of rotation or tipping of teeth is attempted, intrusion prevails before rotation or tipping. However, clear aligner can induce labiolingual tipping or intrusion easily. To achieve preliminary alignment including control of rotation and tipping, NiTi archwires with fixed appliance can be used first, and then clear aligner can be used for finishing in mild Class I maloccusion cases. For this purpose, clear aligner can be made using a digital setup and 3D printing. To move teeth using a clear aligner, tooth capture is critical. To improve tooth capture of clear aligners, slingshot or vertical elastics can be used. These were discussed with illustrations.

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Oblique Single-Cut Rotation Osteotomy for Correction of Femoral Varus-Torsional Deformities in 3D-Reconstructed Canine Bone Models

  • Kim, Hyeon-Ho;Roh, Yoon-Ho;Lee, Je-Hun;Jeong, Jae-Min;Jeong, Seong Mok;Lee, Hae Beom
    • Journal of Veterinary Clinics
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    • v.37 no.4
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    • pp.180-184
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    • 2020
  • The purpose of this study was to report the reliability and validity of oblique single-cut rotation osteotomy (OSCRO) in 3D-reconstructed canine bone models with femoral varus and torsional deformities. A healthy adult male beagle was recruited to create a 3D bone model, and this bone model was modified by using a 3D program. Fifteen bone models were constructed for this study. OSCRO simulation was performed in accordance with the plan after printing using a 3D printing machine. The anatomical lateral distal femoral angle (aLDFA), anteversion angle (AA), anatomical caudo-distal femoral angle (aCdDFA), mechanical caudo-distal femoral angle (mCdDFA) and pre- and postoperative bone length were calculated. There were no significant differences between the target values and postoperative values. In addition, the difference between pre- and postoperative bone length was small (p = 0.001). Our findings suggest that OSCRO could be an effective surgical option for MPL with bone deformities in small-breed dogs that often undergo conventional distal femoral osteotomy.

On low cost model-based monitoring of industrial robotic arms using standard machine vision

  • Karagiannidisa, Aris;Vosniakos, George C.
    • Advances in robotics research
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    • v.1 no.1
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    • pp.81-99
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    • 2014
  • This paper contributes towards the development of a computer vision system for telemonitoring of industrial articulated robotic arms. The system aims to provide precision real time measurements of the joint angles by employing low cost cameras and visual markers on the body of the robot. To achieve this, a mathematical model that connects image features and joint angles was developed covering rotation of a single joint whose axis is parallel to the visual projection plane. The feature that is examined during image processing is the varying area of given circular target placed on the body of the robot, as registered by the camera during rotation of the arm. In order to distinguish between rotation directions four targets were used placed every $90^{\circ}$ and observed by two cameras at suitable angular distances. The results were deemed acceptable considering camera cost and lighting conditions of the workspace. A computational error analysis explored how deviations from the ideal camera positions affect the measurements and led to appropriate correction. The method is deemed to be extensible to multiple joint motion of a known kinematic chain.

Selective Muscle Activation With Visual Electromyographic Biofeedback During Scapular Posterior Tilt Exercise in Subjects With Round-Shoulder Posture

  • Son, Jae-ik;Lim, One-bin;Han, Hae-rim;Cynn, Heon-seock;Yi, Chung-hwi
    • Physical Therapy Korea
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    • v.22 no.4
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    • pp.17-26
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    • 2015
  • The purpose of this study was to investigate the effects of visual electromyography (EMG) biofeedback on the EMG activity of the lower trapezius (LT), serratus anterior (SA), and upper trapezius (UT) muscles, the LT/UT and SA/UT EMG activity ratios, and the scapular upward rotation angle during scapular posterior tilting exercise (SPTE). Twenty-four subjects with round-shoulder posture participated in this study. The EMG activities of the LT, SA, and UT were collected during SPTE both without and with visual EMG biofeedback. The scapular upward rotation angle was measured at the baseline, after SPTE without visual EMG biofeedback, and after SPTE with visual EMG biofeedback. The LT, SA, and UT EMG activities, and the LT/UT and SA/UT EMG activity ratios were analyzed by paired t-test. The scapular upward rotation angle was statistically analyzed using one-way repeated analysis of variance. If a significant difference was found, a Bonferroni correction was performed (p=.05/3=.017). The EMG activities of LT and SA significantly increased, and the EMG activity of UT significantly decreased during SPTE with visual EMG biofeedback compared to SPTE without visual EMG biofeedback (p<.05). In addition, the LT/UT and SA/UT EMG activity ratios significantly increased during SPTE with visual EMG biofeedback compared to SPTE without visual EMG biofeedback (p<.05). Significant increases were found in the scapular upward rotation angle after SPTE without and with visual EMG biofeedback compared to baseline (p<.017), and no significant differences were observed in the scapular upward rotation angle between SPTE without and with visual EMG biofeedback. In conclusion, SPTE using visual EMG biofeedback may be an effective method for increasing LT and SA activities while reducing UT activity.

Estimation of Rotational Center and Angle for Image Stabilization (영상 안정화를 위한 회전중심 및 각도 추정기법)

  • Seok, Ho-Dong;Yoo, Jun;Kim, Do-Jong
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.7
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    • pp.611-617
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    • 2004
  • This paper presents a simple method of rotational motion estimation and correction for roll axis stabilization of an image. The scheme first computes the rotation center by taking least squares of selected local velocity vectors, and the rotational angle is found from special subset of motion vectors. Roll motion correction is then performed by the nearest neighbor interpolation technique. To show the effectiveness of our approach, the synthetic and real images are evaluated, resulting in better performance than the previous ones.

The Rotational Motion Stabilization Using Simple Estimation of the Rotation Center and Angle

  • Seok, Ho-Dong;Kim, Do-Jong;Lyou, Joon
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.231-236
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    • 2003
  • This paper presents a simple approach on the rotational motion estimation and correction for the roll stabilization of the sight system. The algorithm first computes the rotational center from the selected local velocity vectors of related pixels by least square methods. And then, rotational angle is found from the special subset of the motion vector. Finally, motion correction is performed by the nearest neighbor interpolation technique. In order to show the performance of the algorithm, the evaluation for the synthetic and real image was performed. The test results show good performance compared with previous approach.

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CASE REPORTS OF ANTERIOR CROSSBITE CORRECTION TREATED BY HORSESSHOE APPLIANCE (Horseshoe Appliance에 의한 전치부 반대교합 치험예)

  • Chung, Kyu-Rhim;Kim, Soo-Cheol;Cho, Eun-Soo
    • The korean journal of orthodontics
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    • v.14 no.2
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    • pp.273-285
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    • 1984
  • The present paper describes 4 clinical cases of Hellman dental age III A group of functional Class III malocclusion in which the horsehoe appliance was applied to obtain normal anteroposterior relationship between jaws. What is the most noteworthy in the result from the use of this appliance is that minimum down and backward rotation during backward repositioning of the mandible is noticed and the excellent retentive property in itself makers allowance for effective orthopedic correction in mixed dentition with anterior crossbite.

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Development of a Mathematical Model for Effect of Scoliosis Surgical Correction (구조해석을 통한 척추측만증 교정 분석에 필요한 모델 개발)

  • 김영은;최형연;손창규;이광희;이춘기
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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    • pp.1059-1061
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    • 2002
  • A FE model is to develop a personalized biomechanical model of the scoliotic spine that will allow the design of clinical test providing optimal estimation of the post-operation results. A flexible multi-body model of the spine including rib cage, clavicle, and scapular was developed to simulate several mobility simulations. Vertebrae, clavicle and scapular were represented using rigid bodies and ribs and sternum were modeled as flexible bodies. Kinematical Joints and spring elements were used to represent the intervertebral disc and ligaments respectively. Postero-anterior and lateral radiographics of a scoliotic spine were used to represent a 3D reconstruction. CT data for same patient were also used to verify vertebrae rotation driven from postero-anterior and lateral radiographic images. Simulated results showed good reducibility almost uniformly distributed along the spinal segments. It was also found that boundary and loading conditions, required to mimic the operation procedures, were proven to be very sensitive parameters to its results rather than its mechanical properties

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A study on the geometric correction for the digital subtraction radiograph (디지털 공제방사선영상의 기하학적 보정에 관한 연구)

  • Lim Suk-Young;Koh Kwang-Joon
    • Imaging Science in Dentistry
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    • v.31 no.1
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    • pp.23-34
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    • 2001
  • Purpose : To develop a new subtraction program for registering digital periapical images based on the correspondence of anatomic structures. Materials and Methods: The digital periapical images were obtained by Digora system with Rinn XCP equipment after translation of 1-16 mm, and rotation of 2-20° at the premolar and molar areas of the human dried mandible. The new subtraction program, NIH Image program and Emago/Advanced program were compared by the peak-signal-to noise ratio (PSNR). Results : The new subtraction program was superior to NIH Images program and Emagol Advanced program up to 16 mm translation and horizontal angulation up to 4°. Conclusion: The new subtraction program can be used for subtracting digital periapical images.

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