• The korean journal of orthodontics
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• v.14 no.1
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• pp.161-172
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• 1984

This study was undertaken to evaluate the cephalometric changes of the soft tissue and skeletal profile subsequent 10 the rapid palatal expansion in 25 Angle's Class III cases, ranging in age from six to fifteen years, with cross-bite of the anterior teeth, underdevelopment of maxilla and facial disharmony Following results were obtained: 1. ANS moved downward, Point A presented forward & downward movement increasing SNA and Point B presented backward & downward movement decreasing SNB. 2. Mandible was rotated to backward & forward and maxilla moved forward & downward with the bite opening and improvement of anterior teeth cross-bite. 3. Soft tissue on mandible was rotated to backward & forward following hard tissue changes causing the decrease of facial convexity angle and backward & downward rotation of Point B', Pog'. 4. Response of the upper lip was more significant in downward than forward direction, and correlated with the upper central incisor and mandible rotation. 5. Response of the lower lip was more significant in downward than backward direction, and correlated with the mandible rotation. 6. There was a rather high degree of correlation between skeletal profile and soft-tissue profile, 1 : LS, $\bar{1}$:Pog', Pog:LS, Pog:LI, Pog:Pog' in horizontal measurements and $\bar{1}$:Pog', Pog:LI, Pog:Pog' in vertical measurements.

• The korean journal of orthodontics
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• v.45 no.5
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• pp.226-235
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• 2015

Objective: The purpose of this retrospective study was to investigate short-term and long-term skeletodental outcomes of Class III activator treatment. Methods: A Class III activator treatment group (AG) comprised of 22 patients (9 boys, 13 girls) was compared with a Class III control group (CG) comprised of 17 patients (6 boys, 11 girls). The total treatment period was divided into three stages; the initial stage (T1), the post-activator treatment or post-mandibular growth peak stage (T2), and the long-term follow-up stage (T3). Cephalometric changes were evaluated statistically via the Mann-Whitney U-test and the Friedman test. Results: The AG exhibited significant increases in the SNA angle, ANB angle, Wits appraisal, A point-N perpendicular, Convexity of A point, and proclination of the maxillary incisors, from T1 to T2. In the long-term follow-up (T1-T3), the AG exhibited significantly greater increases in the ANB angle, Wits appraisal, and Convexity of A point than the CG. Conclusions: Favorable skeletal outcomes induced during the Class III activator treatment period were generally maintained until the long-term follow-up period of the post-mandibular growth peak stage.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.2
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• pp.172-178
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• 2000

When we establish treatment planning of facial asymmetry, we must predict each asymmetrical element that will be changed upon coronal, axial, sagittal plane. At the visual point, prediction of the change of coronal plane is most important. It is important difference between Rt. and Lt. mandibular angle belonging to posterior coronal plane, as well as anterior coronal plane, such as upper and lower incisor, or midline of chin point. Several methods for control bulk of mandibular angle are additional angle shaving after osteotomy, grinding contact area between proximal and distal segment for decrease the volume, or bone graft for increase the volume. But, at the point of bimaxillary surgery, transverse position of posterior maxilla is an important factor for control it. So, we would report transverse movement of posterior maxilla for decrease asymmetry on the posterior coronal plane of face, that is, asymmetry of mandibular angular portion.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.2
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• pp.278-285
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• 2000

This paper presents the basic characteristics of the beam tilting dipole antenna element in which one reactance element is used for the impedance matching at the feed point. The radiation pattern is tilted by the properly determined driving point position, and the loading reactance is used to obtain forced resonance without great changes in tilt angle. The numerical results demonstrate that the reactance element should be loaded in the region where the driving point is placed to obtain forced resonance of the antenna with little changes in beam tilt angle. In case the proposed forced resonant beam tilting antenna with $0.8\lambda$ length is driven at $0.2\lambda$ from the center, the main beam tilt angle o.5 57.7 degrees, the highest power gain of 8.6 dB are obtained.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.9
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• pp.12-20
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• 2022

Delamination and burr defects are important problems in drilling fiber reinforced plastics. A method for measuring FRP drilling defects has been studied. Delamination and burr factors were defined as the relative length or area. Using these factors, the effects of tool shape and drilling conditions on delamination and burr were studied. In this study, the defects that occur when drilling a glass-carbon fiber hybrid composite were compared in terms of three factors. In the glass-carbon fiber hybrid composite, the effects of the feed rate and tool point angle on the delamination and burr factors were similar to those in previous studies. The diameter of the tool did not affect the defect factor. A circular burr was generated in a drill tool with a point angle of 184°, and a relatively small deburring factor was observed compared with a tool with a point angle of 140°.

• Journal of Oral Medicine and Pain
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• v.25 no.2
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• pp.205-214
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• 2000

This study was performed to investigate the relationship between mandibular midline shift and anteroposterior first molar occlusal relation, and their effects on the mandibular height and the occlusal plane angle. For this study, 49 patients with temporomandibular disorders were selected. They did not show facial asymmetry and their facial midline coincide with maxillary dental midline. Upper and lower mandibular impression were taken and the casts were fabricated. Amount and direction of the mandibular midline shift and the anteroposterior shift between the two occluding first molars were measured on the casts. Several items related to height such as mandibular height from top of the articular surface of the condyle to curve changing point between antegonial notch and mandibular angle, condylar height which was the vertical distance from the articular surface to retroepicondyle of the condyle, and sigmoid height from the deepest point of sigmoid notch to the curve changing point and the occlusal plane angle were also measured on the panoramic and on the transcranial radiographs. Correlation between midline shift and anteroposterior first molar relation and comparison between right and left mandibular height by the midline shift and the first molar relation were analysed by SPSS windows program. The results of this study were as follows : 1. Mean amount of midline shift in the subjects with midline shift were 2.0mm for both side, respectively. The first molar relation of the ipsilateral side of midline shift showed Angle class II tendency and the contralateral side showed Angle class III tendency, which meant drift of the dentition to the side of the midline shift. 2. The occlusal plane angle on the panoramic radiograph were $13.0^{\circ}$ in right, and $12.5^{\circ}$ in left side, and their were no correlation between occlusal plane angle and mandibular midline shift and the first molar occlusal relation. 3. Angle's classification for both sides of the first molar relation were same in about half of all the subjects. Amount of deviation from class I first molar relation, however, were decreased in the contralateral side of observed side. 4. Mandibular height of the ipsilateral side to which mandibular midline shift showed tendency of lower than that of the contralateral side, and there was a tendency that the height was higher in class III subjects, then class II subjects, and lower in class I subjects. However, condylar height did not show any difference in the subjects with midline shift and also show no difference by the first molar occlusal relation.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.943-946
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• 1998

In this paper, we applied FFT to PCB Images, cutting unnecessary singals and noise, moving the starting point to center of image and used rotaion transform. from the detected edge Hough Transform identify the length, but not the angle, so we matched PCB images with using rotation transform to identify length and angle. After rotation transform we employ Least Squared Method to exact stereo matching.

• Journal of Advanced Marine Engineering and Technology
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• v.21 no.1
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• pp.37-42
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• 1997

Turbulent flow characteristics of a two - dimensional oblique plate impinging jet(OPIJ) were experimentally investigated. The jet mean velocity and turbulent intensity profIles were also measured along the plate. The jet Reynolds numbers(Re, based on the nozzle width)ranged from 10, 000 to 35, 000, the nozzle - to - plate distance(H/B) from 2 to 16, and the oblique angle (a) from 60 to 90 degree. It has been found that the stagnation point shifted toward the minor flow region as the oblique angle decreases and the position of the stagnation point nearly coin¬cided with that of the maximum turbulent intensity.

• Journal of Electrical Engineering and Technology
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• v.5 no.4
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• pp.666-671
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• 2010

Multi-layer perceptron neural networks have been constructed to classify four types of defects in steam generator tubes. Three features are extracted from the signals of the eddy current testing method. These include maximum impedance, phase angle at the point of maximum impedance, and an angle between the point of maximum impedance and the point of half the maximum impedance. Two hundred sets of these features are used for training and assessing the networks. Two approaches are involved to train the networks and to classify the defect type. One is the conjugate gradient method and the other is the Broydon-Fletcher-Goldfarb-Shanno method which is recognized as the most popular algorithm of quasi-Newton methods. It is found from the computation results that the training time of the Broydon-Fletcher-Goldfarb-Shanno method is much faster than that of the conjugate gradient method in most cases. On the other hand, no significant difference of the classification performance between the two methods is observed.

• Journal of the Korean Society of Industry Convergence
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• v.8 no.3
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• pp.143-148
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• 2005

This paper presents a hybrid method for recognizing the faces by using principal component analysis(PCA) and fixed-point independent component analysis(FP-ICA). PCA is used to whiten the data, which reduces the effects of second-order statistics to the nonlinearities. FP-ICA is applied to extract the statistically independent features of face image. The proposed method has been applied to the problems for recognizing the 20 face images(10 persons * 2 scenes) of 324*243 pixels from Yale face database. The 3 distances such as city-block, Euclidean, negative angle are used as measures when match the probe images to the nearest gallery images. The experimental results show that the proposed method has a superior recognition performances(speed, rate). The negative angle has been relatively achieved more an accurate similarity than city-block or Euclidean.