• Transactions on Control, Automation and Systems Engineering
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• v.4 no.4
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• pp.347-355
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• 2002

Obstacle avoidance of underactuated robot manipulators using switching computed torque method (SCTM) is presented. One fundamental feature of this novel method is to use partly stable controllers (PSCs) in order to fulfill the ultimate control objective. Here, we use genetic algorithms (GAs) to acquire the optimum switching sequence of the control actions for a given time frame with the available set of elemental controllers, depending on which links/variables are controlled. The effectiveness of the concept is illustrated by taking a three-degrees-of-freedom (DOF) manipulator and showing enhanced performance of the proposed control methodology.

• Journal of computational fluids engineering
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• v.3 no.2
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• pp.9-16
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• 1998

Predictive behaviors by the extended k-${\varepsilon}$ turbulence model and the standard k-${\varepsilon}$ turbulence model are compared. Grid dependency is tested with the H-type grid as well as the O-type grid. Computations have been performed on a circular-to-rectangular transition duct. The Reynolds number is 390,000 based on the bulk velocity at the inlet. The computed axial velocity contours, transverse velocity profiles, static pressure contours, peripheral skin friction coefficient, peripheral wall static pressure distributions and turbulence kinetic energy have been compared with experimental results. The computed results than those obtained with the standard k-${\varepsilon}$ turbulence model. Comparing to the computed results obtained with the H-type grid and O-type grid, those with H-type grid seem to agree well with experimental results.

• The korean journal of orthodontics
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• v.45 no.2
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• pp.66-73
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• 2015

Objective: To compare condylar position and morphology among different vertical skeletal patterns. Methods: Diagnostic cone-beam computed tomography images of 60 adult patients (120 temporomandibular joints) who visited the orthodontic clinic of Hallym University Sacred Heart Hospital were reviewed. The subjects were divided into three equal groups according to the mandibular plane angle: hypodivergent, normodivergent, and hyperdivergent groups. Morphology of the condyle and mandibular fossa and condylar position were compared among the groups. Results: The hypodivergent and hyperdivergent groups showed significant differences in superior joint spaces, antero-posterior condyle width, medio-lateral condyle width, condyle head angle, and condylar shapes. Conclusions: Condylar position and morphology vary according to vertical facial morphology. This relationship should be considered for predicting and establishing a proper treatment plan for temporomandibular diseases during orthodontic treatment.

• Imaging Science in Dentistry
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• v.44 no.4
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• pp.315-320
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• 2014

Root resorption is loss of dental hard tissue as a result of clastic activities. The dental hard tissue of permanent teeth does not normally undergo resorption, except in cases of inflammation or trauma. However, there are rare cases of tooth resorption of an unknown cause, known as "idiopathic root resorption". This report would discuss a rare case of multiple idiopathic resorption in the permanent maxillary and mandibular teeth of an otherwise healthy 36-year-old male patient. In addition to a clinical examination, the patient was imaged using conventional radiography and cone-beam computed tomography (CBCT). The examinations revealed multiple external and internal resorption of the teeth in all four quadrants of the jaws with an unknown cause. Multiple root resorption is a rare clinical phenomenon that should be examined using different radiographic modalities. Cross-sectional CBCT is useful in the diagnosis and examination of such lesions.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.1
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• pp.100-104
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• 1998

A hybrid control method based on 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 method is illustrated through several simulations.

• Transactions of Materials Processing
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• v.18 no.5
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• pp.422-427
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• 2009

Computed tomography(CT) has been applied to measure micro-defects in the aluminum knuckle parts manufactured by the thixoforming process. 6061 aluminum alloys were used to form knuckle samples in the semi-solid temperature after the SIMA processing of billets. Tensile specimens were cut from the different locations in a thixoformed knuckle. The size and the distribution of forming defects in tensile specimens were analyzed using CT scanning and image analysis technology before tensile tests. It has been qualitatively shown that the stress-strain curves were significantly affected by the size and the distribution of forming defects although the defect sizes lie in the range of micro-meters.

• Journal of Veterinary Clinics
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• v.19 no.2
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• pp.256-259
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• 2002

A 39 kg, 7-year-old male Labrador Retriever dog with a 3-month history of epistaxis, sneezing, and nasal discharge was referred to the Veterinary Medical Center of the Tokyo University. On the plain X-ray and computed tomography (CT) of the head showed increased density of the soft tissue in the left nasal cavity and the tumor infiltrated to nasal septum. The tumor mass removed by rhinotomy. Histopathological examination of the mass revealed adenocarcinoma. Four weeks after the surgery, the radiation therapy was performed twice a week for f weeks. 4 months after surgery, the dog had a recurrence in nasal cavity and administered carboplatin 300 mg/$m^2$ twice. However, the tumor had no response to chemotherapy, additional surgery and additional radiation therapy, and the dog was euthanized at the owner's request. At necropsy, metastatic proliferation was confirmed in the lung, lymph nodes and nasal cavity.

• Journal of the Korean Society of Radiology
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• v.9 no.2
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• pp.109-115
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• 2015

In case of a CT examinations, there is a difference in the distribution of radiation dose from that of general X-ray equipments, and it has been known to cause a great radiation exposure during the examinations. However, owing to its high reliability on the accuracy of a examinations result, its use has increased continuously. In consideration of such a circumstance, the CT equipment, radiation dose during CT examinations, diagnostic reference level, and solutions to reduce radiation dose were mentioned on the basis of previously reported data.

• Journal of Chest Surgery
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• v.28 no.12
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• pp.1183-1187
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• 1995

We have experienced a case of communicating bronchopulmonary malformation. A 35-year-old female patient was admitted for coughing with sputum. About eight years ago, she had treated for bronchiectasis with medication. Chest computed tomography revealed esophagopulmonary communication with upper esophageal dilatation and bronchiectasis of the left lower lobe. A about 3 mm diameteded abnormal feeding vessel from descending thoracic aorta to the left lower lobe was detected at operation. Division and closure of the communication between the esophagus and left lower lobe was performed. Communicating bronchopulmonary malformation is the rare form of pulmonary sequestion and chest computed tomography is one of the useful diagnostic methods for pulmonary sequestion.

• Journal of radiological science and technology
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• v.14 no.2
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• pp.9-14
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• 1991

Chest radiograms obtained by using Fuji Computed Radiography(FCR) system were compared to conventional film/screen radiograms. The FCR images showed better image quality in diagnostic informations than the conventional chest images. In FCR, the radiation exposure to patient for chest examination could be reduced up to one tenths of conventional chest examination. The main advantages or FCR were considered to depend on the contrast processing and frequency processing properties. The use of FCR in clinical work may improve both diagnostic quality and radiation exposure.