• 구강회복응용과학지
• /
• 제23권2호
• /
• pp.139-144
• /
• 2007

Prosthodontic treatment planning for various edentulous arches is not an easy issue for dentists. Especially, in case of removable partial denture, we must have a knowledge of overall treatment procedures, and a careful approach is needed. Recently, interest of dental implant and case reports are increasing, the decrease of the removable partial denture is true, but dental implantation takes longer treatment period and it is more expensive. Also, there are still some limitations like lack of available alveolar bone, patient's general condition, and chronic periodontitis. Therefore, sometimes implantation is impossible. Finally, implantation cannot be adapted to every single patient. Currently, the clasp type removable partial dentures are used routinely, giving patients many unesthetic and functional difficulties. With better laboratory technique, removable partial denture with attachment and removable partial denture in rigid type increase patient's happiness level much more than predicted. The case presented in this article, clinically demonstrate the efficiency of using a telescopic system to improve esthetic and functional recovery for patients who lose multiple teeth.

• Imaging Science in Dentistry
• /
• 제30권3호
• /
• pp.229-234
• /
• 2000

Cleidocranial dysplasia (previously known as cleidocranial dysostosis) is a well-known, rare and hereditary skeletal disorder characterized by a variety of dental abnormalities and as its name implies, striking involvement of the cranial vaults and clavicles. A 17-year-old female who presented with short stature and prolonged retention of deciduous teeth, subsequent delay in eruption of permanent teeth is described. She could touch her shoulders together at the midline anteriorly. Diagnostic procedures showed hypoplasia of the maxillary and zygomatic bones, open fontanelles and sutures, and aplasia of the clavicles. The paranasal sinuses were absent or underdeveloped. Characteristically, she had near parallel-sided borders in the ascending ramus of the mandible and abnormal-shaped, the slender pointed coronoid process. The zygomatic arches had a downward bend and discontinuity at the zygomaticotemporal suture area. Radiographic and clinical investigations of her cranial and skeletal abnormalities revealed features of cleidocranial dysplasia.

• Journal of Genetic Medicine
• /
• 제10권2호
• /
• pp.109-112
• /
• 2013

Treacher Collins syndrome (TCS) is the most common and well known mandibulofacial dysostosis with characteristic clinical features including downward slanting of palpebral fissures, coloboma of the lower eyelid, hypoplastic zygomatic arches, micrognathia, macrostomia, microtia, and other deformities of the ears. TCS is caused by mutations in at least 3 genes involved in pre-rRNA transcription: TCOF1, POLR1D and POLR1C. We experienced a 1-day-old female infant with characteristic clinical features of TCS. A novel, heterozygotic mutation within the TCOF1 gene (c.3874_3875insG, p.Ala1292Glyfs*30) was identified to cause a premature stop codon.

• 천문학회보
• /
• 제42권1호
• /
• pp.33.3-33.3
• /
• 2017

현재 관측되는 대부분의 성단들은 구형의 구조를 보이는 반면, 별탄생 지역은 구형의 구조와는 다른 프랙털(fractal) 구조를 보이고 있다. 본 연구에서는 초기에 프랙털 구조를 가지는 성단이 우리 은하 중심부근에서 어떻게 진화하는지 N-body 시뮬레이션을 이용해 연구하였다. 그 결과, 프랙털 구조의 성단이 우리 은하 중심부근의 강력한 조석력장 내에서 살아남기 위해서는 초기 밀도가 높아야 한다는 것을 발견하였다. 성단의 초기 밀도가 높기 때문에 프랙털 구조의 성단은 빠른 역학적 진화를 보이며 구형의 성단으로 진화한다. 플러머 (Plummer) 구조의 성단도 프랙털 구조의 성단과 같이 초기 밀도가 높아야 살아남지만 프랙털 구조보다는 역학적인 진화가 느렸다. 이러한 결과들은 Arches 성단처럼 우리 은하 중심부근에서 관측되는 성단들의 형성과 진화에 제약조건을 줄 수 있을 것으로 예상된다.

• 대한심미치과학회지
• /
• 제10권2호
• /
• pp.9-14
• /
• 2001

Autotransplantation of tooth has recently become a combined method with orthodontic therapy. With the use of autotransplantation, it has become possible for orthodontists to solve complicated problems in the dental arches. Autotransplanted teeth showed the same development as their contralaterals with respect to both eruption and root growth. This indicates that autotransplantation and orthodontic treatment is a method that should be considered in case of impacted, missing, or malformed teeth. In this report two cases are presented to demonstrate that orthodontic treatment with autotransplantation can contribute to more satisfactory solution to the problem for impacted teeth.

• 한국안전학회지
• /
• 제12권4호
• /
• pp.220-229
• /
• 1997

곡선보(curved beam)의 등분포 하중하에서 평면내(in-plane)와 평면의(out-of-plane)의 좌굴(buckling)을 해석하는데 differential quadrature method (DQM)을 이용하여 다양한 경계조건(boundary conditions)과 굽힘각(opening angles)에 따른 입계하중(critical loads)을 계산하였다. DQM의 해석결과는 해석적 해답(exact solution) 또는 다른 수지해석 결과와 비교하였으며, DQM은 적은 요소(grid points)를 사용하여 정확한 해석결과를 보여주었다. 두 경계조건(고정-고정, 고정-단순지지)하에서 새로운 결과를 또한 제시하였다.

• 한국조명전기설비학회지:조명전기설비
• /
• 제4권1호
• /
• pp.41-45
• /
• 1990

교량 부각 조명 및 교각 조명 계획의 과정과 요소를 고찰함으로써 교량 조형물 외부 조명 계획의 주요 문제를 추론하고 그 해결 방안 및 체계적인 접근을 위한 설계의 기초 방안을 제시하고자 한다. 본 연구에서 한강대교의 아아치와 교각부각조명과 잠실대교의 수중보 부각조명을 통하여 각 계획의 제한 조건하에서의 설계목적의 부합성, 유지보수의 용이성, 설계효과의 극대화를 달성하기 위한 설계제한조건의 해결 방법을 모색하였다.

• Structural Engineering and Mechanics
• /
• 제45권5호
• /
• pp.703-722
• /
• 2013

In this paper a study about concrete arch bridges built by lattice cantilevers is presented. Lattice cantilevers are partial structures composed of deck, arch, piers and provisional steel diagonals, organized as reticular cantilever girders, in order to build arch bridges without the use of centrings, supports or temporary towers. Characteristics of this construction methodology with its variants are explained together with their implications in the erection sequence. Partial elastic scheme method is implemented in order to find initial forces of temporary cables and a forward analysis is carried out to follow the actual sequence of construction, by extending a procedure already applied to concrete cable-stayed bridges and to arches built by the classical suspended cantilever method. A numerical application on a case-study of a concrete arch bridge is performed together with a comparison between different methodologies followed for its construction sequence. Differences between erection by lattice cantilevers and cable-stayed cantilevers, are discussed. Results can be useful for designers in conceptual design of concrete arch bridges.

• 치과방사선
• /
• 제6권1호
• /
• pp.39-44
• /
• 1976

The study was performed in order to avoid misunderstanding of the image production in the orthopantomograph and auther tried artificially, the object was not placed on the image layer children who was in mixed dentition was taken with 3 sheets of the film at one time. The results were obtained as following; 1. If the object was placed in front of the image layer and back of it, width of the anterior teeth was narrowed and widened. 2. If the object's midline was not placed on the median line of the equipment, the one side was narrowed and the another side was widened. 3. If the head was inclined upward and downward, the former was shown V shape and the latter was shown inverted V shape outline of the arches. 4. In mixed dentition, auther obtained in each other that the image layer was placed on the deciduous arch, on the permanent arch, in the middle of the deciduous teeth and permanent teeth at one exposure.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2003년도 추계학술대회논문집
• /
• pp.492-497
• /
• 2003

The dynamic instability for snapping phenomena has been studied by many researches. There is few paper which deal with the dynamic buckling under the load with periodic characteristics, and the behavior under periodic excitation is expected the different behavior against STEP excitation. We investigate the fundamental mechanisms of the dynamic instability when the sinusoidal shaped arch structures subjected to sinusoidal distributed excitation with pin-ends. In this study, the dynamic direct snapping of shallow arches is investigated under not only STEP load excitation but also sinusoidal harmonic excitations, applied in the up-and-down direction. The dynamic nonlinear responses are obtained by the numerical integration of the geometrically nonlinear equations of motion, and examined by the Fourier spectral analysis in order to get the frequency-dependent characteristics of the dynamic instability for various load levels.