• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2003년도 봄 학술발표회 논문집
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• pp.225-232
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• 2003

The behaviour of ground induced by tunneling of 2arch tunnels may differ from the one caused by usual type tunnels. This paper describe the behaviour created by the size of pilot tunnel and the condition on the construction method of center piller Also, loads acting on the supports of the first tunnel and the center pillar during the excavation of second tunnel is investigated by numerical analyses. The results of numerical analyses are compared to the data records of measurement results, i.e. force on the support system and ground displacement.

• 대한치과의사협회지
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• 제37권8호통권363호
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• pp.608-613
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• 1999

During diagnostic process of the orthodontic patients, it is not unusual to find palatally erupted canines. Palatally erupted canines are related with the positional abnormalities rather than the tooth size/arch-length discrepancies. It is very important to conserve the original arch shape during traction of palatally erupted canines to their proper position. On the following case, the patient was diagnosed as malocclusion with palatally erupted canines, and were treated by 0.9mm auxiliary arch wire during traction of ectopic canines for maintenance of the original arch shape.

• 한국공간구조학회논문집
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• 제16권4호
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• pp.83-89
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• 2016

Middle size of membrane retractable roof is under 25m span which consists of various moving systems. Trolley is the system that leads the membrane to parking place, transferring the load from the membrane to structural cable. When membrane closes roof completely, thus, structural behavior of trolley, which may contain various material with different friction coefficients, should be investigated by vertical load. Nummerical simulation of trolley prototypes, in this research, was performed by incrementation of vertical load. Consequently, this paper studied proper friction characteristics and provided the effective inner materials of trolley.

• Wind and Structures
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• 제39권1호
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• pp.71-84
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• 2024

The wind-resistant performance of bridges is generally evaluated based on the strip assumption. For the arch rib of arch bridges, the situation is different due to the curve axis and the variable cross-sectional size. In the construction stage, the arch rib supported by a cable system exhibits flexible dynamic characteristics, and the wind-resistant performance attracts specially attention. To evaluate the wind-induced vibration of an arch rib with the maximum cantilever state, the finite element model was established to compute the structural dynamic characteristics. Then, a three-dimensional (3D) fluid-solid coupling analysis method was realized. After verifying the reliability of the method based on a square column, the wind-induced vibration of the arch rib was computed. The vortex-induced vibration (VIV) performance of the arch rib was focused and the flow field characteristics were discussed to explain the VIV phenomenon. The results show that the arch rib with the maximum cantilever state had the possibility of VIV at high wind speeds but the galloping was not observed. The lock-in wind speeds were larger than the results based on the strip assumption. Due to the vibration of arch rib, the frequency of shedding vortices along the arch axis trended to be uniform.

• 대한치과교정학회지
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• 제24권4호
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• pp.819-826
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• 1994

This study was designed to get the knowledges of the ideal arch form of the class I malocclusion patients of Koreans with first premolar extraction. The subjects consisted of 98 individuals with class I malocclusion with first premolar extraction. The results were as follows ; 1 Author found the ideal arch shape of the class I malocclusion patients with first premolar extraction. 2. Equations of ideal arch form of the class I malocclusion patients with first premolar extraction were obtained from SPSS.

• 대한치과교정학회지
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• 제24권4호
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• pp.773-785
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• 1994

It has been generally believed that the impaction or eruption of mandibular third molars has significant correlations with the growth of the mandible, size of mandibular arch and size of teeth. The purpose of this study was to examine if there is any correlation between the status of eruption of mandibular third molars and the amount of mandibular crowding. The effect of missing of third moalrs to mandibular crowding was studied as well. 140 adult students of Yonsei University were selected and divided into three groups according to the status of mandibular third molars, Group 1) congenital missing group, Group 2) eruption group, and Group 3) impaction group. The tooth size, dimensions of the mandibular dental arch, and the amount of crowding were measured and compared. Results were as follows ; 1. There was no statistically significant difference in tooth size between the missing group and the eruption group(p<0.05). Impaction group showed larger total tooth material, inci- sal tooth material, and individual tooth size except central incisors compared to missing group (p<0.05). Impaction group showed larger total tooth material, incisal tooth material compared to eruption group as well(p<0.05). When individual tooth size was compared, impaction group had larger central incisors, canines, and second premolars than eruption group(p<0.05). 2. Missing group showed larger intermolar width than impaction group and it was stati- stically significant(p<0.05). 3. When compared the amount of total crowding, impaction group showed the largest am- ount of crowding, then eruption group, and missing group showed the least amount of crowding respectively(p<0.05). There was no statistically significant difference between missing stoup and eruption group in the amount of incisal crowding(p<0.05). Impaction group show- ed the largest amount of incisal crowding among all three groups(p<0.05).

• 대한치과교정학회지
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• 제34권6호
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• pp.488-496
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• 2004

본 연구는 치아밀집이 과도한 치아크기에 의해 나타나는지 아니면 좁은 치열궁으로 인해 초래되는지 그 원인을 규명하기 위하여 시행되었다. 앵글씨 1급 구치관계를 가지면서 상악 하악 모두 7mm이상의 치아밀집을 나타내는 경우와 정상교합자를 각각 실험군과 대조군으로 설정하였다. 82조(남29, 여53)의 치아밀집 석고모형과 82조(남37, 여45)의 정상교합 석고모형에서 각 치아의 치관 근원심폭경과 협측 및 설측 치열궁 폭경을 측정하고 치아밀집군과 정상교합군 간에 비교한 결과 치관근원심폭경과 치열궁 폭경 모두에서 두 군간의 유의한 차이가 나타났다. 치아밀집의 기여요인을 살펴본 본 연구 결과 치아밀집은 치열궁과 치아크기, 모두에 의해 초래됨으로 치열궁 확장 및 치아발치, 모두가 치료방법으로 사용될 수 있음을 알 수 있었다

• 치위생과학회지
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• 제13권2호
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• pp.197-202
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• 2013

본 연구는 치위생과 학생 147명을 대상으로 체격에 따른 치열궁 크기의 관련성을 조사하고자 실시하였다. 연구를 위해 설문지 작성과 치열궁 장 폭경 계측을 위한 인상채득이 동시에 실시되었으며, 다음과 같은 결론을 얻었다. 1. 1년 이내에 구강검진 경험이 있는 경우는 74.8%, 코로 숨을 쉬는 경우는 86.4%, 교정과 발치경험이 있는 경우는 각각 18.4%, 49.7%로 조사되었다. 정제된 음식은 94.6%가 좋아한다고 응답하였으며, 단단한 음식은 52.4%가 좋아한다고 응답하였다. 2. 치열궁 크기의 관련 요인에 따른 치열궁 장 폭경은 모든 변수가 통계적으로 유의한 차이를 보이지는 못했다. 3. 체격에 따른 치열궁 장 폭경 중 통계적으로 유의한 차이를 나타낸 변수는 신장과 체중이었으며, 신장이 클수록 상악 치열궁 장경이 크게, 체중이 많이 나갈수록 하악 견치간 폭경과 상악 구치간 폭경도 큰 것으로 나타났다. 4. 체중이 많이 나갈수록 상, 하악 견치간 폭경과 상, 하악 구치간 폭경이 약한 양의 상관관계를 보였으며, 상하악 치열궁 장경과 견치간 폭경, 구치간 폭경에서는 상악 구치간폭경과 하악 구치간 폭경이 가장 높은 관련성을 보였다. 이상의 결과로 보아 체격요건 중 체중이 치열궁 형태에 영향을 주었다. 앞으로도 체격변화에 따른 치열궁의 변화를 지속적으로 조사함으로써 안정적인 교합과 구강건강을 위한 자료로 활용할 수 있도록 해야 할 것이다.

• 치위생과학회지
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• 제14권3호
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• pp.390-396
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• 2014

본 연구는 우리나라 여대생의 치열궁의 크기 및 형태와 교합유형을 조사하고 이들의 관련성을 알아보고자 치위생과 여학생 210명을 대상으로 실시하였다. 수집된 자료는 PASW 18.0 프로그램을 이용하여 통계분석하였으며, 결과는 다음과 같다. 치열궁의 크기 및 형태와 교합을 산술평균 및 빈도를 분석한 결과 상악의 견치 간 폭경은 34.38 mm, 제1대구치 폭경은 52.05 mm였으며, 견치 장경은 8.60 mm, 제1대구치장경은 28.69 mm였다. 하악은 견치 간 폭경이 26.42 mm, 제1대구치 폭경이 44.83 mm였으며, 장경은 견치가 5.54 mm, 제1대구치가 24.38 mm였다. 치열궁의 형태는 상악에서 정상이 29.0%, 협착이 60.5%, 공극이 10.5%였으며, 하악은 정상이 29.0%, 협착이 55.7%, 공극이 15.2%였다. 교합은 정상이 16.7%였으며, I급 부정교합이 55.7%로 가장 많았고, II급은 20.5%, III급은 7.1%였다. 치열궁의 형태와 교합에 따른 치열궁의 크기를 비교한 결과 하악의 제1대구치 폭경이 치열궁의 형태가 공극인 경우에 45.95로 가장 컸으며, 정상이 44.73, 협착이 44.58을 기록하였다(p=0.032). 치열궁 형태와 교합관계는 상 하악 모두 I, II, III급 부정교합에서 협착이 71.8%, 76.7%, 60.0%와 69.2%, 60.5%, 60.0%로 가장 높았다(p<0.001). 이상의 결과를 종합해보면 과거에 비해 여러 원인으로 치열궁의 장 폭경이 줄어들고 있으며, 협착으로 인한 부정교합이 증가하고 있다. 따라서 정기적인 치과검진과 구강악습관의 관리가 필요할 것으로 보인다.

• 대한치과교정학회지
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• 제22권3호
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• pp.675-690
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• 1992

The purpose of this study was to obtain the lingual morphology (size, angulation, contour, eminence) of adults with normal occlusion in order to provide the basic data for lingual bracket and lingual arch form in Korean. The subjects (Male: 50, Female: 50) were selected who have normal occlusion and dental casts were prepared. Tooth size, angulation, arch width, horizontal contour, lingual eminence were measured for all 28 teeth both upper and lower arch. The results were as follows: 1. Measuring items of all individual teeth for adults with normal occlusion were obtained. 2. In comparison tests, there was a statistically difference between intermolar widths $(\underline{6}\;to\;\underline{6})$ before occlusal reduction and intermolar width $(\underline{6}\;to\;\underline{6},\underline{7}\;to\;\underline{7})$ after occlusal reduction only all the other measuring items showed no statistically differences. 3. There was small variation in horizontal contour of lingual surface on lower incisors and upper and lower bicuspids. The other teeth showed somewhat greater variations. 4. There was offset between canine and bicuspid in upper arch while there was no prominent offset in lower arch.