• 대한치과교정학회지
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• 제5권1호
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• pp.57-63
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• 1975

For the purposes of augmentation of the aid for case analysis and diagnosis of malocclusion, a roentgenocephalometric study was made from 84 Korean adolescences. The Subjects consist of 42 males and 42 females aged from 17 to 20 years with normal occlusion and acceptable facial appearance. The author measured 18 angles and 14 linear distances as suggested by Jarabak. The following results were obtained. 1) Each linear measurement of the males' skull was greaten than that of the females. 2) The posterior to anterior facial height was $69.2\%$ in the males and $67.1\%$ in the females. 3) In the relationship of upper lip to esthetic line, the lip of females was more behind than that of males. 4) Saddle angle was $124.7^{\circ}$, articular angle was $148.7^{\circ}$, genial angle was $119.4^{\circ}$ and upper and lower genial angles were $45.1^{\circ}\;(N-Go-a^{\circ})$ and $74.2^{\circ}\;(N-Go-Me^{\circ})$. 5) The ratio of mandibular body to anterior cranial base was about 1:1. 1. 6) The angulations of $SNA^{\circ},\;SNB^{\circ}\;and\;SNP^{\circ}$ were as follows; $SNA^{\circ},\;80.3^{\circ},\;SNB^{\circ},\;79.8^{\circ},\;SNP^{\circ},\;81.1^{\circ}$. 7) The angle of the sella-nasion plane to the mandibular plane $(SNG^{\circ}Me^{\circ})$ was $32.0^{\circ}$ and that of the occlusal plane to the mandibular plane was $18.2^{\circ}$. 8) The angle of the maxillary central incisor to the sellanasion plane $(1-SN^{\circ})$ was $105.6^{\circ}$. That of the mandibular central incisor to the mandibular plane $(1-GoMe^{\circ})$ was $94.0^{\circ}$, and the interincisal angle $(1\;to\;1^{\circ})$ was $127.6^{\circ}$. 9) The linear distance from incisal edge of upper central incisor to facial plane was 8.0mm and that of lower central incisor was 4.6mm. 10) In the relationship of the lower lip to the esthetic line, the lower lip was 0.2mm front of the esthetic line.

• 대한치과교정학회지
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• 제48권5호
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• pp.283-291
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• 2018

Objective: This study was conducted to perform histomorphometric evaluations of the bone surrounding orthodontic miniscrews according to their proximity to the adjacent tooth roots in the posterior mandible of beagle dogs. Methods: Four male beagle dogs were used for this study. Six orthodontic miniscrews were placed in the interradicular spaces in the posterior mandible of each dog (n = 24). The implanted miniscrews were classified into no loading, immediate loading, and delayed loading groups according to the loading time. At 6 weeks after screw placement, the animals were sacrificed, and tissue blocks including the miniscrews were harvested for histological examinations. After analysis of the histological sections, the miniscrews were categorized into three additional groups according to the root proximity: high root proximity, low root proximity, and safe distance groups. Differences in the bone-implant contact (BIC, %) among the root proximity groups and loading time groups were determined using statistical analyses. Results: No BIC was observed within the bundle bone invaded by the miniscrew threads. Narrowing of the periodontal ligament space was observed in cases where the miniscrew threads touched the bundle bone. BIC (%) was significantly lower in the high root proximity group than in the low root proximity and safe distance groups. However, BIC (%) showed no significant differences among the loading time groups. Conclusions: Regardless of the loading time, the stability of an orthodontic miniscrew is decreased if it is in contact with the bundle bone as well as the adjacent tooth root.

• 한국컴퓨터그래픽스학회논문지
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• 제16권2호
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• pp.29-37
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• 2010

본 논문에서는 얼굴의 3차원 스캔 데이터로부터 특징을 고려하여 비대칭적인 요소를 완화시키는 대칭적 변형 기법을 제안한다. 이를 위해 얼굴의 전체 윤곽뿐만 아니라 세밀한 영역까지 다룰 수 있는 얼굴의 특징점과 표면 곡률에 기초한 새로운 3차원 형상 기술자(shape descriptor)를 개발하였다. 개발된 형상 기술자는 이상적인 대칭 평면을 정의하여 정확한 대칭쌍 정점을 결정할 수 있기 때문에, 보다 정교하게 3차원 얼굴의 대칭성을 향상 시킬 수 있다. 또한 변형을 위한 모든 단계에서 처리를 쉽게 하도록 포인트 기반 표현법을 사용하였다. 마지막으로 제안한 대칭적 변형 기법을 통해 얼굴의 비대칭성을 감소시킴으로써 얼굴에 대한 호감도를 향상시킬 수 있다는 것을 통계적으로 검증하였다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제34권1호
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• pp.34-40
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• 2012

Purpose: The study was performed to compare patients with anatomical variations in facial asymmetry with patients in the normal range using cone-beam computed tomography (CBCT) and to take the preoperative condition into consideration in the case of a sagittal split ramus osteotomy (SSRO). Methods: The study was conducted on 46 adult patients composed of 2 subdivided groups, an asymmetry group (n=26) and a symmetry group (n=20). The asymmetry group was divided between patients with hemimandibular hyperplasia (HH, n=8) and hemimandibular elongation (HE, n=18). Using cross-sectional computed tomography images, the thickness of cancelleous bone in the buccal area of the mandible, thickness of buccal cortex in the buccal aspect of the mandible, thickness of cancellous bone in the inferior aspect of the mandible, thickness of buccal cortex in the inferior aspect of the mandible, and cross-sectional surface area of the mandible were measured. Results: In the asymmetry group, the cross-sectional area of the mandible including the inferior alveolar nerve positioned on the affected side was significantly different from the symmetry group. Thickness of cancelleous bone in the buccal aspect of the mandible, thickness of cancelleous bone in the inferior aspect of the mandible, and cross-sectional surface area of the mandible in the affected site of hemimandibular hyperplasia was significantly smaller than in the symmetry group. Conclusion: The inferior alveolar nerve runs lower and in a more buccal direction and shows a smaller cross-sectional surface of the mandible in the hemimandibular hyperplasia patients with asymmetry.

• 대한치과교정학회지
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• 제28권6호
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• pp.937-946
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• 1998

전치부 개교를 동반하는 수직적으로 긴 안모는 임상교정에서 치료하기 어려운 증례중 하나이다. 이런 증례의 특징을 찾기 위한 많은 시도가 있었으나 골격 및 치성 요소에 대한 개별 파악이 이루어지지 않음으로써 일관된 설명 없이 혼돈 만 초래하게 되었을 뿐이다. .수직적으로 긴 안모의 두부방사선계측학적 륵징을 확인하기 위하여 Sn-GoGn 각에 따라 구분된 109개의 치료 전 두부방사선사진 (35 수직군, 37 평균군, 37 수평군)을 분석하여 비교한 결과 다음과 같은 결과를 발견하였다. 수직적으로 긴 안모일수록 전안모고경, 특히 하전안모고경이 증가하며 후안모고경은 짧아지고, 모든 치조골, 특히 상악에서 의 두께가 깊어진다. 또한 모든 골격적 각계측항목이 커지는데 특히 lower genial angle의 상관성이 컸다. 한편 상악 전치는 점점 설측경사되었고 하악 전치는 순측경사되는 경향을 보였다.

• Archives of Plastic Surgery
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• 제36권4호
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• pp.475-480
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• 2009

Purpose: To correct the facial asymmetry and to achieve symmetry and balance, not only the soft tissue restoration of deficits but also creation and facial contour line such as mandible border and angle is important. Micro fat graft has limitation such as high resorption rate and somewhat limited ability to emphasize the rigid bony characteristics of the mandible angle due to its innate soft consistency. We have investigated the advantages of dermal fat graft over micro fat graft to correct asymmetry of the lower face in patients who had undergone mandibular reconstruction or distraction, using comparative analysis. Methods: Total of 12 patients were enrolled in our study: 6 micro fat graft and 6 dermal fat graft. Postoperative results were compared and analyzed at immediate postoperative period and more than 1 year later in each group with photographs, and analysised with image J program. Result: No complications were noted both in the micro fat type and the dermal fat type of procedures such as fat necrosis or micro calcifications. All of the patients who received micro fat graft, however had considerable amount of fat resorption after the procedure which led to two additional fat graft procedures. Although minor contour obliteration due to contracture was seen in patients who had undergone dermal fat graft procedure, no definite resorption was found even after more than one year follow-up. Results of dermal fat graft patients were satisfactory in terms of mandible angle symmetry. Secondary revision was necessary in one case due to overcorrection using dermal fat graft. Conclusion: The dermal fat graft has many advantages over the conventionally more popular micro fat graft to correct asymmetry of the lower face following mandible reconstruction owing to its lower resoption rate, more effective in emphasizing the natural curvilinear anatomical contours of the mandible angle and body and lower complication rates such as fat necrosis or micro calcifications.

• 한국콘텐츠학회논문지
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• 제10권1호
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• pp.19-26
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• 2010

본 논문은 사각형 특징 기반 분류기를 제안하여 실시간으로 얼굴 영역을 검출하며, 계산의 효율성과 검출 성능을 동시에 만족시키는 강인한 검출 알고리즘을 구현하고자 한다. 제안한 알고리즘은 특징 생성, 분류기 학습, 실시간 얼굴 영역 검출의 세 단계로 구성된다. 특징 생성은 제안된 5개의 사각형 특징으로 특징 집합을 구성하며, SAT(Summed-Area Tables)를 이용하여 특징 값을 효율적으로 계산한다. 분류기 학습은 AdaBoost 알고리즘을 이용하여, 분류기를 계층적으로 생성한다. 또한 중요한 얼굴 패턴은 다음 레벨에 반복적으로 적용함으로써 우수한 검출 성능을 가진다. 실시간 얼굴 영역 검출은 생성된 사각형 특징 기반 분류기를 통해, 빠르고 효율적으로 얼굴 영역을 찾아낸다. 또한 얼굴 영역을 검출한 영역을 인식의 입력 영상으로 사용하여 PCA와 KNN 알고리즘을 이용하여 기존의 매칭 방법인 Point to point 방법이 아닌 Class to Class 방식을 이용하여 인식률을 향상시켰다.

• 한국지능시스템학회논문지
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• 제18권1호
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• pp.20-26
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• 2008

지능형 로봇이나 컴퓨터가 일상생활 속에서 차지하는 비중이 점점 높아짐에 따라 인간과의 상호교류도 점점 중요시되고 있다. 이렇게 지능형 로봇(컴퓨터) - 인간의 상호 교류하는데 있어서 감정 인식 및 표현은 필수라 할 수 있겠다. 본 논문에서는 음성 신호와 얼굴 영상에서 감정적인 특징들을 추출한 후 이것을 Bayesian Learning과 Principal Component Analysis에 적용하여 5가지 감정(평활, 기쁨, 슬픔, 화남, 놀람)으로 패턴을 분류하였다. 그리고 각각 매개체의 단점을 보완하고 인식률을 높이기 위해서 결정 융합 방법과 특징 융합 방법을 적용하여 감정 인식 실험을 하였다. 결정 융합 방법은 각각 인식 시스템을 통해 얻어진 인식 결과 값을 퍼지 소속 함수에 적용하여 감정 인식 실험을 하였으며, 특징 융합 방법은 SFS(Sequential Forward Selection) 특징 선택 방법을 통해 우수한 특징들을 선택한 후 MLP(Multi Layer Perceptron) 기반 신경망(Neural Networks)에 적용하여 감정 인식 실험을 실행하였다. 그리고 인식된 결과 값을 2D 얼굴 형태에 적용하여 감정을 표현하였다.

• 대한치과교정학회지
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• 제43권1호
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• pp.42-52
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• 2013

The aim of this paper was to propose a new method of bimaxillary orthognathic surgery planning and model surgery based on the concept of 6 degrees of freedom (DOF). A 22-year-old man with Class III malocclusion was referred to our clinic with complaints of facial deformity and chewing difficulty. To correct a prognathic mandible, facial asymmetry, flat occlusal plane angle, labioversion of the maxillary central incisors, and concavity of the facial profile, bimaxillary orthognathic surgery was planned. After preoperative orthodontic treatment, surgical planning based on the concept of 6 DOF was performed on a surgical treatment objective drawing, and a Jeon's model surgery chart (JMSC) was prepared. Model surgery was performed with Jeon's orthognathic surgery simulator (JOSS) using the JMSC, and an interim wafer was fabricated. Le Fort I osteotomy, bilateral sagittal split ramus osteotomy, and malar augmentation were performed. The patient received lateral cephalometric and posteroanterior cephalometric analysis in postretention for 1 year. The follow-up results were determined to be satisfactory, and skeletal relapse did not occur after 1.5 years of surgery. When maxillary and mandibular models are considered as rigid bodies, and their state of motion is described in a quantitative manner based on 6 DOF, sharing of exact information on locational movement in 3-dimensional space is possible. The use of JMSC and JOSS will actualize accurate communication and performance of model surgery among clinicians based on objective measurements.

• 한국정보전자통신기술학회논문지
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• 제13권3호
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• pp.206-211
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• 2020

얼굴검출 과정은 영상 모니터링에서 매우 중요한 과정이며 생체 인식 기술의 한 종류이다. 검출과정은 변수가 많고 복잡하여 하드웨어가 발전하고 있는 근래에 와서 소프트웨어적인 발전이 이루어지고 있다. CCTV를 이용하는 분야 중 얼굴 검출 기술은 얼굴을 분석하기 이전에 실행되는 과정으로 영상에서 얼굴이 있는 곳을 찾아내는 기술이다. 사람의 얼굴은 조명이나 피부 색, 방향과 각도, 표정 등 여러 가지 환경적 조건에 따라 민감한 반응을 하기 때문에, 얼굴 검출에 관한 연구는 많은 어려움이 있다. 얼굴 검출 기술의 활용성과 중요성은 시간이 지날수록 각광받고 있으나, 얼굴 검출 이전에 선행되어야 하는 얼굴 영역 검출 기술에 대해서는 간과하는 측면이 많다. 본 논문의 시스템은 AdaBoost detector에서 검출 못하는 기울어진 얼굴을 검출할 수 있어 다른 사물의 검출도 같은 기술을 사용할 수 있을 것이다.