• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.6 s.177
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• pp.1513-1519
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• 2000

This paper proposes a hybrid control method of using impedance control and the computed-torque control for biped robot locomotion. Computed torque control is used for supporting (constrained) leg. For the free leg, the impedance control is used, where different values of impedance parameters are used depending on the gait phase of the biped robot. To reduce the magnitude of an impact and guarantee a stable footing when a foot contacts with the ground, this paper proposes to increase the damping of the leg drastically and to modify the reference trajectory of the leg. Computer simulations with a 3 -dof environment model for which a combination of a nonlinear and a linear compliant models is used, show that the proposed controller is superior to the computed-torque controllers in reducing impacts and stabilizing the footing.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.25-29
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• 2006

The object of this study is to develop new examination techniques for measuring the O-ring deformation behavior under the pressure condition. The extrusion lengths measured from the computed tomography were in good agreement with the results that measured from non-contact laser displacement sensor. The deformed shapes of O-ring measured by the computed tomography and evaluated by the FEM agreed well with the extrusion length and the expanded diameter. But the contact widths of the O-ring and steel measured by the computed tomography were a little larger than the results of the FEM.

• Imaging Science in Dentistry
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• v.41 no.1
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• pp.23-28
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• 2011

Purpose : This study was to find the computed tomographic features of fibrous dysplasia of the maxillofacial region. Materials and Methods : All eight cases included in the study reported either to Government Dental College and Hospital or Nair Hospital Dental College, Mumbai between 2003 and 2009. The patients were prescribed computed tomogram in addition to conventional radiographs of maxillofacial region which were studied for characteristic features of fibrous dysplasia. The diagnosis of fibrous dysplasia was confirmed by histopathological report. Results : All cases showed the ill-defined margins of lesions except in the region where the lesions were extending to cortex of the involved bone. Internal structure of all cases showed ground glass appearance. Four cases of maxillary lesion showed the displacement of maxillary sinus maintaining the shape of maxillary sinus. Two cases showed complete obliteration of maxillary sinus. Displacement of inferior alveolar canal did not follow any typical pattern in any of the cases but was displaced in different directions. Conclusion : The craniofacial type of fibrous dysplasia is as common as fibrous dysplasia of jaw. The margins, extent, internal structure and effect on surrounding structure are well detected on computed tomographic images.

• Journal of Veterinary Clinics
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• v.32 no.1
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• pp.69-72
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• 2015

This study was performed to differentiate calcium oxalate and struvite canine urinary stones using computed tomography. A total of 38 urinary stones (8 calcium oxalate and 30 struvite) were scanned using a computed tomography scanner. These urinary stones (10-15 mm diameter) extracted surgically without fragmentation were obtained from the different individual patients. The stone's Hounsfield units(HU) values, heterogenicity, and roughness of surface were evaluated to differentiate calcium oxalate and struvite. The HU values of calcium oxalate were significantly higher than those of struvite. A receiver operator characteristic (ROC) curve revealed 1272 as the best threshold value to distinguish calcium oxalate from struvite (ROC curve AUC 0.87, p < 0.0014). The heterogenicity of calcium oxalate and struvite significantly differed on bone and dental window setting (p < 0.0001). There was no significant difference between calcium oxalate and struvite in roughness of surface. On computed tomographic images, bone and dental windows setting were useful for evaluation of heterogenicity between calcium oxalate and struvite. The HU value and heterogenicity are highly promising factor that can distinguish calcium oxalate and struvite with reasonable accuracy.

• Journal of Veterinary Clinics
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• v.35 no.6
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• pp.290-293
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• 2018

Signalment: A dog which had been hit by car a month prior and had been experiencing recurrent pleural chyle effusion was referred to Chung-buk National University Animal Medical Center. The clinical signs included tachypnea and salivation. Results: Ultrasound-guided popliteal lymphography was performed. The computed tomography imaging revealed that the thoracic duct was ruptured and the lymph was leaking into the cranial mediastinal region. After this discovery, thoracic duct ligation was performed. The ultrasound-guided popliteal lymphography was repeated after the surgery. The second computed tomography imaging revealed that the thoracic duct rupture was resolved. Clinical relevance: We identified the etiology of chylothorax through the computed tomographic lymphography and imaged specific leakage areas. After surgery, the computed tomography imgaing confirmed the lymphatic flow modification and the treatment was successful.

• Electronics and Telecommunications Trends
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• v.12 no.6 s.48
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• pp.50-57
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• 1997

CT스캔(Computed Tomography)은 다양한 분야에서 효과적으로 응용되고 있고, 특히 의학 영상에서 비침범 진단, 수술 계획 등에 커다란 영향을 끼쳤다. 이 글에서는 여러 가지 CT스캔의 종류, 그 수학적인 원리와 기본적인 평행 광선(parallel beam)을 이용한 영상의 재구축 알고리즘, 데이터의 추정과 문제점 그리고 그 개선 방향에 대해 논한다

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1577-1580
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• 1997

A hybrid control method based on using the relative motion between a manipulator and a workpiece is described for a two-dimensional manipulator, in which it is assumed that there are no collisions between the robot manipulator and the workpiece, and that we use a computed force law which is similar to the computed torque law in the trajectory tracking problem of a robot manipulator. The effectiveness of the proposed hybrid control emthod is illustratec by some simulations.

• Journal of Korean Neurosurgical Society
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• v.48 no.1
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• pp.31-36
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• 2010

l death via apoptosis in human gliomas.

• Proceedings of the KIEE Conference
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• 1988.11a
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• pp.68-71
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• 1988

The purpose of this paper is to compare with the simulated results of two control algorithms control algorithm in the real time, based upon the model. These control schemes are "Computed-torque" and "Feedforward-Dynamics compensation", and have been simulated on the CMU DD Arm II.

• The Journal of the Korean dental association
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• v.48 no.10
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• pp.729-737
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• 2010

The use of cone-beam computed tomography(CBCT) image has been increased. Usually, the dentists use this images for the implant or orthodontic treatment. In this article, CBCT examples for oral surgery and endodontics are presented. CBCT is very useful when dentists extract teeth or provide endodontic treatment. The disadvantage of the CBCT image is also discussed simply. Clinicians could provide higher quality of medical care with CBCT.