• 제목/요약/키워드: Occlusions

검색결과 185건 처리시간 0.026초

청소년기 정상교합자의 전치부 피개도에 관한 연구 (A STUDY ON OVERBITE AND OVERJET OF THE ANTERIOR SEGMENT WITH NORMAL OCCLUSION)

  • 박인권;유영규;백형선
    • 대한치과교정학회지
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    • 제13권2호
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    • pp.185-192
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    • 1983
  • The purpose of this study was to determine the mean value of overbite and overjet, and to find the correlation among overbite, overjet and relative maxillofacial structures using the data from orthodontic casts and cephalometric films of boys and girls aged from 9 to 18 years with normal occlusions. The results were obtained as follows: 1. Incisal overbite depth was decreased from Group I to Group III. 2. The highest value of correlation coefficient with incisal overbite was 0.368 of incisal angle. in Group III. 3. Overjet was not significantly correlated with the age and sex. 4. Ratio of mesiodistal diameters of upper and lower incisors was not significantly correlated with overbite and overjet.

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Bioprogressive Therapy에 의한 Angle II급 1류 부정교합의 교정치험예 (Case Reports of Angle's Class II, Division 1 malocclusions treated by Bioprogressive Therapy)

  • 정규림
    • 대한치과교정학회지
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    • 제13권2호
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    • pp.209-222
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    • 1983
  • Three patients who had Angle's Class II Division 1 malocclusion were treated by Bioprogressive therapy. In spite of their occlusions, the 3 patients did not have any skeletal problems. Their skeletal patterns were within normal range. So headgear or functional appliance therapy were not considered. During the treatment procedure, the most noteworthy results of Bioprogressive therapy were the effect of the Utility arch to intrude 4 mandibular anterior teeth, the effect of the Cuspid retractor in cuspid retraction and the effect of the Double delta retraction arch in the retraction of 4 anterior teeth. The whole treatment results in these cases which were achieved by Bioprogressive therapy were very favorable and the efficiency of this therapy was very excellent.

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하악골의 측방운동 및 전방운동 형태와 이에 따른 치아 동요도에 관한 통계학적 연구 (The Statistical Study of Tooth Mobility on the Occlusion Patterns)

  • 이명호
    • 대한치과보철학회지
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    • 제22권1호
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    • pp.79-84
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    • 1984
  • The stability of teeth is an important measure of the periodontal health. This study was designed to determine if there was a relation between the patterns of disclusion and a tooth mobility. An evaluation was made on 117 persons with Angle's class I occlusion who were free from histories of orthodontics, removable or fixed prosthesis, and anterior crowding or open contacts. The results were as follows: 1. In this study, 17.52% of the subjects were exhibited canine protected occlusion. 2. In protrusive movements, 75.21% of the subjects were exhibited incisor guided occlusion and the subjects of canine guided occlusion was the smallest. 3. The canine tooth of mouths having canine-protected occlusions had slightly lower mean tooth mobility scores than the canine of mouths having group function occlsion, but there was no significances. 4. The tooth mobility score of central incisor had higher than that of lateral incisor.

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간내 하공정맥 폐색증의 수술요법 (Surgical Correction of Intrahepatic Inferior Vena Cava Obstruction)

  • 이정렬
    • Journal of Chest Surgery
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    • 제18권1호
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    • pp.128-139
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    • 1985
  • Seven patients [six women and one man] with obstruction of hepatic portion of inferior vena cava was operated on, from May, 1969 to January, 1985. Of seven patients, six were undergone corrective operation for IVC obstruction and another one was not operated because of far advanced liver cirrhosis. The occlusions were found at or close to the level of diaphragm and they were membranous or diffuse with or without thrombi. Most of their symptoms were referable to either inferior vena caval or hepatic venous obstruction and onset of the symptoms was usually gradual, beginning between the age of their thirties and forties. Most of the patients showed marked elevation of peripheral venous pressure of lower extremity [29-40 cm H2O] preoperatively, which decreased significantly after corrective operation [17-30 cm H2O]. Venous catheterization for pressure study and venography were essential for confirming the diagnosis. Of six cases, in which corrective operations were done, Transatrial membranotomy with or without IVC dilatation were performed in five cases [case 1, 2, 3, 5, 6], using cardiopulmonary bypass and in another one case, bypass operation between IVC, distal to obstruction, and RA was done using Dacron tube graft under the thoracoabdominal incision. All survived and their conditions were improved.

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Model-Based Robust Lane Detection for Driver Assistance

  • Duong, Tan-Hung;Chung, Sun-Tae;Cho, Seongwon
    • 한국멀티미디어학회논문지
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    • 제17권6호
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    • pp.655-670
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    • 2014
  • In this paper, we propose an efficient and robust lane detection method for detecting immediate left and right lane boundaries of the lane in the roads. The proposed method are based on hyperbolic lane model and the reliable line segment clustering. The reliable line segment cluster is determined from the most probable cluster obtained from clustering line segments extracted by the efficient LSD algorithm. Experiments show that the proposed method works robustly against lanes with difficult environments such as ones with occlusions or with cast shadows in addition to ones with dashed lane marks, and that the proposed method performs better compared with other lane detection methods on an CMU/VASC lane dataset.

SEGMENTATION WITH SHAPE PRIOR USING GLOBAL AND LOCAL IMAGE FITTING ENERGY

  • Terbish, Dultuya;Kang, Myungjoo
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제18권3호
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    • pp.225-244
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    • 2014
  • In this work, we discuss segmentation algorithms based on the level set method that incorporates shape prior knowledge. Fundamental segmentation models fail to segment desirable objects from a background when the objects are occluded by others or missing parts of their whole. To overcome these difficulties, we incorporate shape prior knowledge into a new segmentation energy that, uses global and local image information to construct the energy functional. This method improves upon other methods found in the literature and segments images with intensity inhomogeneity, even when images have missing or misleading information due to occlusions, noise, or low-contrast. We consider the case when the shape prior is placed exactly at the locations of the desired objects and the case when the shape prior is placed at arbitrary locations. We test our methods on various images and compare them to other existing methods. Experimental results show that our methods are not only accurate and computationally efficient, but faster than existing methods as well.

단일레이저거리센서를 탑재한 실내용이동서비스로봇의 사람추종 (Human following of Indoor mobile service robots with a Laser Range Finder)

  • 유윤규;김호연;정우진;박주영
    • 로봇학회논문지
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    • 제6권1호
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    • pp.86-96
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    • 2011
  • The human-following is one of the significant procedure in human-friendly navigation of mobile robots. There are many approaches of human-following technology. Many approaches have adopted various multiple sensors such as vision system and Laser Range Finder (LRF). In this paper, we propose detection and tracking approaches for human legs by the use of a single LRF. We extract four simple attributes of human legs. To define the boundary of extracted attributes mathematically, we used a Support Vector Data Description (SVDD) scheme. We establish an efficient leg-tracking scheme by exploiting a human walking model to achieve robust tracking under occlusions. The proposed approaches were successfully verified through various experiments.

칼만 필터와 차량 특징 정보를 이용한 중첩된 다중 차량 추적에 관한 연구 (A Study on tracking of multiple vehicle occlusions in road images using Kalman filter and vehicle feature information)

  • 강은구;김성동;최기호
    • 한국통신학회논문지
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    • 제26권4B호
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    • pp.491-504
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    • 2001
  • 본 논문은 고정된 카메라를 통해 들어오는 도로연상에서 추적되는 다중 차량들의 겹침(occlusion)발생시 칼만 필터와 차량의 특징정보를 이용하여 개별 차량을 분할하고 추적 가능한 시스템을 제안하고 구현하였다. 다중 차량을 추적할 시 가장 큰 문제점이 되고 있는 차량 겹침을 해결하기 위해 카메라와의 거리를 이용하여 해결하는 방법 3D 모델을 이용하여 해결하는 방법, 겹침 추론 등 차량 겹침을 해결하기 위한 여러 가지 방법들이 제시되고 있다. 그러나 영상에 연속적으로 나타나는 다중 차량의 겹침을 단일 차량으로 인식할 수 는 단점이 있다. 따라서 칼만 필터와 차량의 특징 정보로서 차량의 높이와 넓이의 비, 추적에 사용되는 박스에서 차량과 여백의 비를 이용함으로서 연속적으로 나타날 수 있는 차량 겹침을 분할하고 추적 가능하게 하는 시스템을 구현하고 실험하였다. 본 시스템에서는 256X 256의 크기로 15 frames/sec로 저장된 AVI 파일 형식의 동영상을 사용하여 실험에 이용하였으며, 시내 도로에서의 차량들의 실험 결과 기존의 방법 보다 차량 특징 정보를 이용한 방법이 연속적 겹침에 대한 처리에 우수함을 보였다.

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정상 교합자의 치관 경사도에 관한 연구 (A STUDY OF THE CROWN INCLINATION IN NORMAL OCCLUSIONS)

  • 정돈영;손병화;박영철
    • 대한치과교정학회지
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    • 제16권1호
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    • pp.155-165
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    • 1986
  • Recently, straight-wire appliance is widely used with great concern in clinical orthodontic field. The purpose of this study was to collect the information of the straight-wire appliance and to determine the crown inclination in clinical orthodontics. The author analyzed the study model of 78 individuals with normal occlusion. The obtained results were as follows. 1. Mean, maximum value, minimum value and standard deviation of crown inclination of upper and lower teeth were obtained. 2. The lingual crown inclination of upper tooth had constant value from first premolar through second molar, the lingual crown inclination of lower tooth progressively increased from canine through second molar. 3. As Howes' ratio was decreased, the crown inclination of upper incisors was increased. 4. Narrowing the upper arch, the crown inclination of upper incisors was increased.

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Characterization of Motion Interpolation in 120Hz Systems

  • Shin, Byung-Hyuk;Kim, Kyung-Woo;Park, Min-Kyu;Berkeley, Brian H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.681-684
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    • 2008
  • Motion interpolation is adopted and has been spread widely into market since it is effective in reducing motion blur, which is considered as weak characteristic due to slow response time of liquid crystal and hold-type display. 120Hz driving using interpolated frames achieves better moving picture quality with less motion blur and less motion judder. However, errors in the interpolated frames can cause visual artifacts such as static text breakup, halos, and occlusions. This paper focuses on categorizing characteristics of visual artifacts and on reducing side-effects by using information from original frames in special cases.

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