• Restorative Dentistry and Endodontics
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• 제11권1호
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• pp.33-41
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• 1985

The purpose of this study was to determine the extent of tooth structure crazing when pinhole were drilled in dentin at various distances from the dentionenamel junction, and when pins were inserted by hand wrench and Auto-klutch handpiece. Sixty freshly extracted teeth were embedded in blocks of cold-curing acrylic resin to a level 1mm apical to the cementoenamel junction, the crown of the teeth were removed to a level 1.5mm coronal to the cementoenamel junction. After being sectioned, the cut surface of the teeth were smoothed, and they were divided into 4 groups. Group I : 4 pinholes were drilled with self-threading Minim spiral drill and pins were inserted with hand wrench in fifteen teeth. Group II : 4 pinholes were drilled with self-threading Minim spiral drill and pins were inserted with Auto-klutch handpiece in fifteen teeth. Group III : 4 pinholes were drilled with self-threading Regular spiral drill and pins were inserted with hand wrench in fifteen teeth. Group IV : 4 pinholes were drilled with self-threading Regular spiral drill and pins were inserted with Auto-klutch handpiece in fifteen teeth. The cut surface were then examined microscopically for the presence or absence of craze line. The results were as follows: 1. The self-threading Minim pin groups (Group I & II) produced less craze lines than did the self-threading Regular pin groups (Group III & IV). 2. In the self-threading Minim pin groups, there was more craze lines with hand wrench (Group I) than with Auto-klutch handpiece (Group 11). 3. In the self-threading Regular pin groups, there was more craze lines with hand wrench (Group III) than with Auto-klutch handpiece (Group IV). 4. Placement of the pinhole at 0.0mm from the dentionenamel junction produced more craze lines than placed at 0.5mm, 1.0mm (p<0.05), however there was no statistically significant between the 0.5mm and 1.0mm distance.

• 한국터널지하공간학회 논문집
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• 제2권3호
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• pp.59-69
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• 2000

3차원 광파기 계측장비와 당사에서 개발한 핵심부품인 Target Pin 및 자료처리 분석프로그램 TEMS3D을 통합한 3차원 광파기 계측시스템을 구축하여 터널의 시공중 내공변위 및 천단침하를 계측하였다. 적용결과 천단침하 계측 및 전방지반 예측 측면에서 시스템의 효용성을 검증하였다. 터널의 유지관리 단계의 내공변위 계측을 위해 DOCS시스템을 지하철 단면에 적용하여 계측치의 진동, 시스템의 검증, 열차 운행, 터널내 온도변화 및 고전압에 의한 영향을 검토하여 향후 유지관리 방안을 제시하였다.

• 대한치과보철학회지
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• 제53권3호
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• pp.215-221
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• 2015

심한 마모를 가진 환자의 치료에서 광범위한 보철 수복을 필요로 하는 경우가 있는데, 마모의 원인과 수직 고경의 변화 유무 등을 판단하여 현재 구강상태의 회복과 장기간의 안정성을 이루어야 한다. 수직 고경을 증가시킬 때는 임시 수복을 하고 장기간의 관찰을 통해 환자의 적응을 평가해야 한다. 본 증례의 환자54세 남자 환자로 전반적인 치아 마모와 심미적 불만족을 주소로 내원하였다. 환자의 구강 내 소견 상 교모와 부식이 동반되어 과도한 마모가 발생한 것으로 진단하였다. 수직 고경의 변화를 평가하기 위해 안정위시 악간공극, 발음, 안모, 심미, 임상적 치관 길이, 중절치 절단과 순측 전정과의 수직거리 등을 평가하였고, 교합기의 incisal pin기준으로 수직 고경을 2.5 mm 증가하기로 하였다. 임시 보철물을 이용하여 8주의 안정화 기간 이후 최종 보철물을 제작하였다. 6개월 간 경과 관찰 결과 기능적, 심미적으로 양호한 결과를 보였다.

• Journal of Forest and Environmental Science
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• 제9권1호
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• pp.1-9
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• 1993

잣송이 수확기계의 개발을 위한 기초자료를 얻기 위하여 강원대학교 임과대학 부속연습림에서 7영급 및 4영급의 착과한 잣나무의 정단부위 성장특성과 착과특성을 1992년 8월 말부터 9월 중순까지 조사하였다. 1. 당년 성장한 가지의 길이는 4영급에서 주지는 27~56cm이고 측지는 18~47cm로 7영급보다 훨씬 왕성하였다. 2. 측지의 분지각은 $24{\sim}89^{\circ}$이었고, 2년 성장한 주지의 직경은 10~30mm로서 두 특징에 있어 영급간 유의적인 차이가 없었으나, 1년생 주지의 직청은 4영급에서 9~18mm로서 7영급보다 생장량이 더 높았다. 3. 착과수는 평균 5개, 구과 생중량은 평균 272g으로 영급간 유의적인 차가 없었다. 4. 2년 자란 주지의 착과위치는 그 마디 아랫 쪽으로부터 7영급에서는 9.7~33.0cm, 4영급에서는 18.0~51.0cm의 범위인 곳으로 평균위치는 각 마디의 1/2과 4/5되는 위치였다. 5. 착과한 나무에 있어서 구과, 1년생지 및 2년생지를 합한 총생중량의 범위는 1.0~7.4kg이었다.

• Steel and Composite Structures
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• 제20권2호
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• pp.379-397
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• 2016

Due to creep and shrinkage of the concrete core, concrete-filled steel tubular (CFST) arches continue to deform in the long-term under sustained loads. This paper presents analytical investigations of the effects of geometric nonlinearity on the long-term in-plane structural performance and stability of three-pinned CFST circular arches under a sustained uniform radial load. Non-linear long-term analysis is conducted and compared with its linear counterpart. It is found that the linear analysis predicts long-term increases of deformations of the CFST arches, but does not predict any long-term changes of the internal actions. However, non-linear analysis predicts not only more significant long-term increases of deformations, but also significant long-term increases of internal actions under the same sustained load. As a result, a three-pinned CFST arch satisfying the serviceability limit state predicted by the linear analysis may violate the serviceability requirement when its geometric nonlinearity is considered. It is also shown that the geometric nonlinearity greatly reduces the long-term in-plane stability of three-pinned CFST arches under the sustained load. A three-pinned CFST arch satisfying the stability limit state predicted by linear analysis in the long-term may lose its stability because of its geometric nonlinearity. Hence, non-linear analysis is needed for correctly predicting the long-term structural behaviour and stability of three-pinned CFST arches under the sustained load. The non-linear long-term behaviour and stability of three-pinned CFST arches are compared with those of two-pinned counterparts. The linear and non-linear analyses for the long-term behaviour and stability are validated by the finite element method.

• 한국환경생태학회지
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• 제36권6호
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• pp.639-650
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• 2022

미선나무(Abeliophyllum distichum Nakai)는 오직 한반도 일부 지역에 제한적으로 자생하는 특산식물이며, 지구범위 인 IUCN Red List Endangered로 평가·등재되어 있는 이화주성(distyly, 二花柱性) 특성을 가진 희귀식물이다. 본 연구는 미선나무 자생 개체군 8개 지역과 천연기념물 개체군 6개 지역 등 총 14개 지역의 정량조사 결과를 바탕으로 미선나무 이화주성에 따른 개화 특성과 개체군 크기를 비교·분석함으로써 향후 미선나무 개체군에 적합한 현지 내 보전관리방안 정립을 목적으로 수행되었다. 개체군별 출현 개체는 전수조사하였으며, 각 개체의 화기 형태로 장주화·단주화 개체를 식별해 개화 개체를 현장에서 조사·기록 후 분석하였다. 미선나무 전체 출현 개체 수는 총 13,130개체(개화 7,003개체, 미성숙 6,127개체)로 각 개체군의 장주화·단주화 개화 개체 수 적정 균형 상태가 유의적(P<0.05)이지 않고, 불균형한 상태를 나타냈다. 특히, 영동 개체군은 타 개체군 대비 매우 불균형적 형태를 나타내 타 개체군과 비교했을 때 유전다양성이 낮고, 근친교배 가능성이 클 것으로 추정된다. 관리 단위별 평균 개화·결실률은 각각 자생 개체군 39.0%, 8.5%, 천연기념물 개체군 89.2%, 55.3%로 천연기념물 개체군이 자생 개체군 대비 매우 높게 나타났다. 이는 상층 수관 울폐 차이에 따른 임내 광유입 변화와 관계된 생식 생장 크기 차이로 사료된다. 한반도 내 미선나무 전체 점유면적은 23,224.5m²이었고, 천연기념물 개체군이 자생 개체군 대비 개체군 점유 면적은 작으나 밀도는 상대적으로 높게 나타났다. 일정 면적에 대한 보호시설 설치로 개체군 확산에 제약이 있는 천연기념물 개체군 내 주기적인 관리가 천연기념물 개체군 밀도를 높인 주된 요인일 것으로 추정된다. 미선나무 보전을 위해서는 현재 인위적·유전적 교란이 의심되는 천연기념물 집단을 해제하고, 새로운 보호구역을 신규로 지정함으로써 보전 우선 개체군의 확대가 필요하다. 천연기념물 개체군의 경우 문화재청과 지자체에서 자생지 관리가 이뤄지고 있으나 자생 개체군의 경우 관리 주체가 전무한 실정으로 미선나무 전반적 관리에 대한 제도적 개선이 우선적으로 이뤄져야 할 것이다.

• 복식
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• 제22권
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• pp.205-224
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• 1994

It was aimed to study the costume of Koryo dynasty based upon the thirty pictures of Bud-dha to hang on the wall among the existing Buddist paintings. The costume to study were made about 64 years during the King Chung-yol(1286) to the King Chung-jong(1350) which style was mostly related in Won Dynasty. 가) Men's wear ; 1. Hair style and hair dress ; Man tied up a top knot and they put on the hat such as a Kuan Kun and Mo. The young boys binds his hair up one, two, and three knot-s, and tied up with a hair ribbon, A kinds of Kuan-mo were Mine-lu-kuan Yuan-yu-kuan, Nong-kuan, Hae-chi-kuan Pok-du Yun-wha-kuan Yip-mo- and Tu-ku(Helmeto) 2. clothes ; 1) Colour of Koryo King's Mien-ku Kuan costume was not agree with blue and reddish black colour which was used in Yo, Song, Kum and Won Dynasty, however black and greenhish blue colour was agreed with. 2) The king wore T'ung-t'ien-kuan(Yuan-yu-kuan) and the government officials wore Chin-hien-kuan Hae-chi-kuan and Nong-kuan as a court dress. In general the king and the Crown Prince wore a hats which was used in T'ung-t'ien system however sometimes they wore small hats which was cited in literature. 3) Gate guard and upper garment wore colourful costume figured gold colour pattern which was distin-gtive costume system of Koryo. 4) A monk wore big sleeve long skirt big sleeve long jacket long skirt and shoulder scar-f full shoulder scarf or right hand shoulder opened scarf. 5) The Soldiers wore helmet shoulder or scarf pee-back hung-kap, pok-kap, yang-dan-g-kap we-yu-kap kun-kap, and boots and they carried arms. 6) The young boys wore scarf, loin cloth, long skirt, belt neckless, wan-silk, boots and foots wear and wristless. 나) Women's wear ; 1. Hair style and hairs and tied up with a hair ribbon and wore precious ston decorated hair dress wheel shape hair dress pan shaped head dress handkerchif covered hair dress decorated precious stone hair pin silk chippon made of head dress muf-fler shaped hairdress. Boots mocasin hae lee, suk and sandle wored as a shoes depends on the classes. They wore neckless, earing wres-tless and wan-pu-sik. 2. Closthe 1) High rank lade's wore un-kyun attached jacket and jacket sleeves decorated pleats and pleats decorated long skirt apron back apron knot belt, scarf this type is the same with Dang Dynasty five dynasty of china Song, Kum Won, Myung Dynasty and our cos-tume of Poe-hae, and Shilla Dynasty.

• 대한치과기공학회지
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• 제37권3호
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• pp.131-144
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• 2015

Purpose: This study set out to propose plans for more efficient and effective clinical practice by investigating the current state of clinical practice in the field of dental technology and thus provide basic data to develop pre- and post-education programs for clinical practice. Methods: The subjects include dental technicians at dental technical laboratories that were appointed as the place of clinical practice by the Department of Dental Technology of G University. The survey period spanned from December 22, 2014 to January 20, 2015. Total 250 questionnaires were distributed to them, and 190(76.0%) were returned. After excluding 23 whose answers were uncertain or seemed to lack reliability, total 167(66.8%) were used in final analysis. Results: 1. The most frequent practice the student did during clinical practice was articulator attachment, which was followed by pin operation or model making, one's own task and practice, sand and crow sculpturing, burying, casting, and grinding. 2. In case of going through the entire process, porcelain had the most students at 39(23.4%), being followed by crown & bridge at 28(16.8%), clinical model at 23(13.8%), full denture at 17(10.2%), and partial denture at 17(10.2%) in the order. 3. Of the students, 59.8%(30.5% for reinforced basic practice; 29.3% for intensive practice education) said that intensive practice education should be reinforced in school; and 22.3% said that intensive theory and practice education was needed, which indicates that 82.6% voiced their opinion of reinforcing education around practice. 4. The students felt that they lacked diligence, passion, and theoretical knowledge somewhat and were relatively good at clinical adaptation and operational skills. Conclusion: The findings show that the students felt an absolute lack of practice education as the school education was focused on theory and national exams in the field of dental technology, thus raising a need to reinforce practice education. Of all the respondents, 62.9% said there was a need to improve the current education with a focus on jobs. In future, education of dental technology should work to bring up able dental technicians that can perform in clinical dental technology right after graduation by reinforcing job-based practice education.