• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.3
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• pp.178-188
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• 2022

Interim immediate denture is fabricated to minimize the period of edentulousness after removal of the patient's remaining teeth and before delivery of final prosthesis. In the case of using the CAD/CAM system, there is an advantage in that the manufacturing process in the clinic and laboratory can be simplified by overcoming some of the limitations of manufacturing interim immediate dentures in the traditional way. However, there are also disadvantages in that errors occur in the process of transmitting information about the patient's intermaxillary relationship to the digital network of the laboratory, resulting in unstable occlusal relationships or non-esthetic prostheses. To overcome this problem, using the simple and accurate POP BOW system's occlusal plane digital transfer method, it was possible to fabricate an esthetic and functional 3D printed interim immediate denture after removal of the remaining upper and lower anterior teeth.

• The Journal of Advanced Prosthodontics
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• v.15 no.6
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• pp.281-289
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• 2023

PURPOSE. This study aimed to predict the positional coordinates of incisor points from the scan data of conventional complete dentures and verify their accuracy. MATERIALS AND METHODS. The standard triangulated language (STL) data of the scanned 100 pairs of complete upper and lower dentures were imported into the computer-aided design software from which the position coordinates of the points corresponding to each landmark of the jaw were obtained. The x, y, and z coordinates of the incisor point (X_P, Y_P, and Z_P) were obtained from the maxillary and mandibular landmark coordinates using regression or calculation formulas, and the accuracy was verified to determine the deviation between the measured and predicted coordinate values. Y_P was obtained in two ways using the hamularincisive-papilla plane (HIP) and facial measurements. Multiple regression analysis was used to predict Z_P. The root mean squared error (RMSE) values were used to verify the accuracy of the X_P and Y_P. The RMSE value was obtained after crossvalidation using the remaining 30 cases of denture STL data to verify the accuracy of Z_P. RESULTS. The RMSE was 2.22 for predicting X_P. When predicting Y_P, the RMSE of the method using the HIP plane and facial measurements was 3.18 and 0.73, respectively. Cross-validation revealed the RMSE to be 1.53. CONCLUSION. Y_P and Z_P could be predicted from anatomical landmarks of the maxillary and mandibular edentulous jaw, suggesting that Y_P could be predicted with better accuracy with the addition of the position of the lower border of the upper lip.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.46 no.3
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• pp.50-56
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• 2009

Recently, according to the product variety of multimedia content some problems are occurred as like an illegal copying, an illegal distribution and a copyright infringement etc. So, for the solution of these problems, some methods were proposed as like watermarking which inserts the information of copyright to the content and the cipher for authentication to DRM which prevents an illegal copying using RSA. In this paper, the multimedia fingerprint based on BIBD code is inserted to the bit-plane of the image content for DRM with RSA, and while the decoding processing. The experiment is operated with the consideration of the image transmission and the transformation. As a result it confirmed that the multimedia fingerprint code inserted in image is detected 60% upper at AWGN 7dB and detected completely 100% at AWGN 10dB upper on PSNR 30, 40, 70 and 80 of Stirmark attacks.

• The korean journal of orthodontics
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• v.21 no.2 s.34
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• pp.419-432
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• 1991

The purpose of this study is to observe how the Class III intermaxillary elastics act upon the craniofacial structures of mixed dentition with anterior crossbites. The cephalometric headplafes of 16 childrens treated only with Class III elastics (C III elastics group) and 23 childrens treated with Class III elastics and Reverse pull headgear simultaneously (C III elastics + RPHG group) were traced, digitized and statistically analyzed. The results were as follows. 1 . Anterior displacement of maxilla was observed in both groups. 2. Simultaneous Class III elastics and reverse pull headgear group showed the counterclockwise rotation of maxilla, however Class III elastics group manifested no rotational change of maxilla. 3. Simultaneous Class III elastics and reverse pull headgear group showed the downward and backward rotation of mandible, however Class III elastics group manifested no rotational change of mandible. 4. Counterclockwise canting of occlusal plane, labial tipping of upper incisor and lingual tipping of lower incisor and mesial displacement of upper molar to pterygoid root vertical were observed in both groups.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.3
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• pp.463-469
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• 1996

Sonoring is caused by the repeated obstructions of versatile upper air way structure during sleep and is known as a kind of disease entity varing from simple snoring to obstructive sleep apnea syndrome(OSAS) which can cause serious cardiopulmonary complications due to its hypoxic pathophysiology. It has been reported that over 30% of middle-aged person have the problems of snoring and its accompanied symptomes and signs. Cephalometric measurements, frequently used to measure sella-nasion-subspinale(SNA) and sella-nasion-supramentale(SNB) angles, can provide the informations about the posterior airway space(PAS), the mandibular plane(MP) and the position of hyoid bone. These informations are useful in determining the therapeutic modalities of the snoring and OSAS patients. However, with conventional routine upright position, it does not represent the actual images of obstructive mechanism during sleep but only show the images of awaken normal upper airway anatomy. Therefore we have taken dual images of a routine upright lateral and a supine cephalometric view to compare both.

• Journal of Chest Surgery
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• v.18 no.2
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• pp.293-298
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• 1985

Cor triatriatum is a rare congenital malformation of the heart in which a septum stretches in a transverse plane through the left atrium, thus creates two left atrial subchambers. The upper one connects with the pulmonary veins, and the lower connects with the left ventricles. Due to the rarity of, and difficulty in diagnosing car triatriatum, data on the surgery of the disease are of necessity and very limited. A case of cor triatriatum combined with atrial septal defect and persistent left superior vena cava was experienced in November, 1984 in Chonnam University Medical School. There was a transverse septum in the left atrium below atrial septal defect, all pulmonary veins were drained into the upper chamber of the left atrium which connected with the right atrium via atrial septal defect and the lower chamber via an oval opening[8mm] in the abnormal septum and the lower chamber was connected with the left atrial appendage, and the left ventricle via mitral valve. There was persistent left superior vena cava drained to left atrium and coronary sinus. The abnormal transverse septum within the left atrium was completely excised and the atrial septal defect was repaired with Woven Dacron patch. The post-operative course was not eventful and the patient was discharged to home with good result on the 15th postoperative day, and has been in good condition upto now.

• Geomechanics and Engineering
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• v.10 no.1
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• pp.59-76
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• 2016

The non-linear Hoek-Brown failure criterion has been widely accepted and applied to evaluate the stability of rock slopes under plane-strain conditions. This paper presents a kinematic approach of limit analysis to assessing the static and seismic stability of three-dimensional (3D) rock slopes using the generalized Hoek-Brown failure criterion. A tangential technique is employed to obtain the equivalent Mohr-Coulomb strength parameters of rock material from the generalized Hoek-Brown criterion. The least upper bounds to the stability number are obtained in an optimization procedure and presented in the form of graphs and tables for a wide range of parameters. The calculated results demonstrate the influences of 3D geometrical constraint, non-linear strength parameters and seismic acceleration on the stability number and equivalent strength parameters. The presented upper-bound solutions can be used for preliminary assessment on the 3D rock slope stability in design and assessing other solutions from the developing methods in the stability analysis of 3D rock slopes.

• Structural Engineering and Mechanics
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• v.21 no.2
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• pp.205-220
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• 2005

This paper presents the possibilities of adapting artificial neural networks (ANNs) to predict the dimensionless parameters related to the maximum contact pressures of an elasticity problem. The plane symmetric double receding contact problem for a rigid stamp and two elastic strips having different elastic constants and heights is considered. The external load is applied to the upper elastic strip by means of a rigid stamp and the lower elastic strip is bonded to a rigid support. The problem is solved under the assumptions that the contact between two elastic strips also between the rigid stamp and the upper elastic strip are frictionless, the effect of gravity force is neglected and only compressive normal tractions can be transmitted through the interfaces. A three layered ANN with backpropagation (BP) algorithm is utilized for prediction of the dimensionless parameters related to the maximum contact pressures. Training and testing patterns are formed by using the theory of elasticity with integral transformation technique. ANN predictions and theoretical solutions are compared and seen that ANN predictions are quite close to the theoretical solutions. It is demonstrated that ANNs is a suitable numerical tool and if properly used, can reduce time consumed.

• The korean journal of orthodontics
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• v.13 no.1
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• pp.45-62
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• 1983

To recognize the problems in malocclusion by roentgenocephalograms, the author designed a new pentagonal frame based on maxillary and mandibular bones. The subjects consisted of 44 normal occlusions (20 male and 24 female), 44 Class II division 1 malocclusions (15 male and 29 female) and 67 Class III malocclusions (31 male and 36 female). The results are as follows; 1. In normal group, the maxillary and mandibular skeletons of female we placed more closely to FH plane, so more anteriorly and upward than those of male. 2. In normal group, the posterior vertical height is longer in male than in female and the upper anterior teeth of female are in more labioversion than those of male. 3. By the X, Y coordinate values in pentagonal frame, it is helpful to recognize certain problems in malocclusions. 4. The posterior vertical height is a good indicator in detecting Angle's Class III malocclusion. 5. The maxillary and mandibular body length, the anterior point of maxillary and mandibular body length and the axial inclination of upper and lower anterior teeth can be useful in discerning Angle's Class II & Class III malocclusion.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.9
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• pp.1147-1153
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• 1999

The attitude control of a double inverted pendulum with a periodical disturbance at link top is dealt in this paper. The proposed system is consisted of the double inverted pendulum and a disturbing link; a triple inverted pendulum with two motors. The lower link is hinged on the plate to free for rotation in the vertical plane. The upper link is connected to the lower link through a DC motor. The DC motor is used to control the posture of the pendulum by adjusting the position of the upper link. The periodical disturbance can be generated by the additional like attached at the end of link 2 through another DC motor, which is the modeling of a posture for a biped supporting with one leg. The motor for the joint simulates the knee joint(or hip joint) and the disturbance for the legs moving in air. The algorithm for controlling the proposed inverted pendulum which is regarded as a virtual double inverted pendulum with a periodic disturbance, is consisted of a state feedback control and a fuzzy logic controller connected in parallel. The fuzzy controller keeps the center of gravity of the biped within the specified range through the nonlinear feedback compensator. The state feedback control takes over the role to maintain a desired posture regardless the disturbance at the link top. Simulations with a mathematical model and experiments are conducted to show the validity of the proposed controller.