• 대한치과기공학회지
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• 제18권1호
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• pp.117-127
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• 1996

This study was aimed to help the construction of esthetic dental prosthesis by investigation of the factors affecting on the atterition position and attrition angle of maxillary lateral incisors. Therefore 197 complete cast of maxillary and mandibualar extracted form the student of K. college were subjected for this study, and result throught the study are as follows. 1. None attrite rate of the maxiilary right lateral incisors was about 16.2% and that of the maxillary left lateral incisors was about 32.4% of examined teeth. 2. Throught mesiodistal attrition area 1) It showed that right lateral incisors was the most frequence in attrition of mesial area of incisal edge, and left lateral incisors was the most frequence in attrition of mesial and mid area of incisal edge. 2) It showed that square type arch was more frequence in attrition of all incisal edge, and ovoid type arch was more frequence in the attrition of mid area of incisal edge, and ovoid type arch was more frequence in the attrition of mid area of incisal edge, and taper type arch was more frequence in the attrition of mesial area of incisal edge than it of average frequence of right lateral incisors, by dental arch type. 3) It showed that square type arch was more frequence in the attrition of all area and mid area of incisal edge, and ovoid type arch was more frequence in the attrition of mid area of incisal edge, and taper type arch was more frequence in the attrition of mesial and distal area of incisal edge than it of average frequence of left lateral incisal, by dental arch type. 4) Sex, vertical overlap, horizontal overlap, incisal guide angle, did not affect significantly to throughout mesiodistal attrition, statistically 3. Throughout labiolingual attrition quantity. 1) It showed that throughout labiolingual attrition quantity was more attrition in order of taper type arch < ovoid type arch < square type arch, by dental arch type. 2) It showed that throughout labiolingual attrition qauntity was more attrition when the length of horizontal overlap is shorter than it of other, by horizontal overlap. 3) Throughout labiolingual attrition quantity of right lateral incisors showed that male was more attrition than it of female. 4) Vertical overlap, incisal guide angle, sex on left lateral incisors did not affect significantly to throughout labiolingual attrition, statistically. 4. Attrition angle 1) It showed that average attrition anlge of right lateral incisors were $30{\pm}13.02$ degree, and it of left lateral incisors were $26{\pm}13.37$ degree. 2) It showed that taper type arch have a bigger attrition angle than it of average of lateral incisors, and square tape arch have a smaller attrition angle than it of average of lateral incisors, by dental arch type. 3) It showed that horizontal overlap of 2.1mm above have a bigger attrition angle than it of average, by horizontal overlap. 4) It showed that female have a bigger attrition angle it of male, by sex.

• 대한전자공학회논문지SD
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• 제41권12호
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• pp.43-49
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• 2004

본 논문에서는 슈퍼하이델타(Super High Delta) 실리카 광도파로와 단일 모드 광섬유 사이의 결합손실을 줄이기 위한 모드 크기 변환기를 설계하였다. 새로운 모드 크기 변환기는 물리적 크기를 최소화하기 위해 주기적으로 분리된 테이퍼 도파로를 사용하였으며 공정을 간단히 하기 위해 수평형 테이퍼를 사용하였다. 또한 결합손실을 개선하기 위해 모드 크기 변환기 주변에 트렌치 구조를 삽입하였다. 최적의 모드 크기 변환기 설계에서 결합손실은 트렌치 구조가 삽입되지 않은 경우는 0.33dB/point 이며 트렌치가 삽입된 경우는 0.2dB/point이다.

• Restorative Dentistry and Endodontics
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• 제30권2호
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• pp.95-101
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• 2005

이 연구의 목적은 근단공의 크기가 다양한 치아에서 근단공 확대의 유무에 따른 근관성형시 치아의 미세누출을 평가하기 위함이다. 1근관 치아 60개를 치근첨 상방 5mm에서 절단후 각 치아의 근단공 크기에 따라 큰 근단공 (L) 작은 근단공 (S)으로 나누었다 이 두 군을 치근첨 상방 5mm의 횡단면상 근관의 형태로 원형 (R)과 난형 (O)으로 나누었다(SR, SO, LR, LO). 각 군은 Quantec series Nickel-Titanium (Ni-Ti) rotary file을 이용하여 .02 taper로 성형 후 측방가압법으로 충전하였다. 누출은 40 $cmH_2O$ 압력하에 fluid transport method로 측정하였다. 측정 후 누출이 있는 시편은 .04 taper와 .06 taper로 재근관치료 하여 다세 미세누출을 평가하였다. 통계학적으로 chi-square test와 fisher's exact test를 이용하였다. 결과는 다음과 같다. 1. .02 taper로 성형한 군에서는 근단공의 크기에 따른 미세누출은 통계적으로 유의성이 있었고 (p < 0.05) .04 taper로 성형한 군에서는 통계적으로 유의한 차이를 보이지 않았다 (p > 0.05) .2.근첨 상방 5 mm에서 근관단면의 형태에 따른 미세누출은 통계적으로 유의하지 않았다 (p > 0.05). 3. LR group과 LO group에서는 .02 taper로 성형한 군과 .04 taper로 성형한 군사이에 유의한 차이를 보였다 (p < 0.05).

• 전기전자학회논문지
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• 제25권4호
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• pp.770-773
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• 2021

본 논문에서는 tapering과 ferroelectric(HfO₂)구조가 적용된 3D NAND flash memory의 프로그램 이후 시간경과에 따른 retention특징을 분석했다. Nitride에 trap된 전자는 시간이 지남에 따라 lateral charge migration이 발생한다. 프로그램 이후 시간이 지남에 따라 trap된 전자가 tapering에 의해 두꺼워진 채널 쪽으로 lateral charge migration이 더 많이 발생하는 것을 확인했다. 또한 Oxide-Nitride-Ferroelectric (ONF) 구조는 polarization에 의해 lateral charge migration이 완화되기 때문에 기존 Oxide-Nitride-Oxide (ONO) 구조 보다 문턱전압(V_th)의 변화량이 줄어든다.

• 한국광학회지
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• 제15권1호
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• pp.22-27
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• 2004

본 논문에서는 광도파로와 광섬유사이에서 광손실을 줄이기 위한 모드 크기 변환기를 설계하였다. 설계된 모드 크기 변환기는 주기적으로 분리된 테이퍼 광도파로로 구성된 모드 크기 변환기이며, 공정상의 적용이 용이한 수평 테이퍼 구조를 선택하였다. 높이와 폭이 3$\mu\textrm{m}$${\times}$3$\mu\textrm{m}$이며 1.5%실리카 광도파로의 경우 파장이 1550nm 파장에서 최적의 모드 크기 변환기 설계 파라미터는 테이퍼 영역의 길이가 500$\mu\textrm{m}$이고, 분리된 광도파로의 길이는 5$\mu\textrm{m}$이며, 주기의 Duty-Cycle은 0.95, 광도파로와 광섬유의 접속면에서의 폭은 1.3$\mu\textrm{m}$이였다. 이 때 결합손실은 0.33㏈/point로 광섬유와 광도파로를 직접 연결할 때 보다 1.27 ㏈/point가 감소하였다.

• Restorative Dentistry and Endodontics
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• 제27권5호
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• pp.521-529
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• 2002

The purpose of this study was to compare the shaping time of two shaping methods and the leakage of three different obturation techniques. Ninty three canaled human molar teeth were used, which were randomly divided into two groups of forty teeth each and ten control teeth. After working length determination, the one group was prepared crown-down technique using rotary root canal instruments of GT rotary files .12/20, .10/20, .08/20 and .06/20 taper(Maillefer Instrument SA. Switzerland). The other group was instrumented with Gates Glidden burs(#1, #2, and #3) to coronal preparation and GT rotary files .08/20 and .06/30 taper to apical preparation. Shaping time was measured. After root canals were instrumented, they were divided to three subgroups and obturated as follows : Subgroup 1, obturated with single cone method Subgroup 2, obturated with lateral condensation : Subgroup 3, obturated with continuous wave technique. Three subgroups were obturated using non-standardized gutta-percha cone(Diadent, Korea, .06 or .08 taper) and AH-26(Dentsply DeTrey, Germany) as a root canal cement. Ten unobturated teeth served as positive and negative controls. After immersion in 2% methylene blue solution for 1 month, the teeth were washed during 24h. The teeth were demineralized in 10% nitric acid and dehydrated by immersion in 80, 90 and 100% ethyl alcohol. The teeth were finally cleared and stored in 100% methylsalicylate, and apical dye penetration was evaluated under stereomicroscope(Leica M420, LC, U.S.A)at $\times$8.75 magnification. Liner measurement of dye penetration was assessed with the use of digitalized image analysing system (analySIS, GmbH, Germany) The data were analysed statistically using independent T-test and Two-way ANOVA and Tukey test. The result were as follows 1. In canal prepared with GT$^{TM}$ rotary file, shaphing time taked more than the group of using Gates Glidden drill to coronal preparation without statistical significance (p>0.05) 2. The group of single cone obturation using canal preparation of GT$^{TM}$ rotary files showed significantly more apical leakage than those of lateral condensation and continuous wave technique regardless of shaping method (p<0.05). 3 The group of single cone obturation using canal preparation of GT$^{TM}$ rotary files and Gates Glidden drill showed significantly more apical leakage than those of continuous wave technique regardless of shaping method (p<0.05). 4. Regardless of shaping method, The group of continuous wave obturation showed less apical leakage than those of lateral condensation without statistical significance (p>0.05). 5. The group of single cone obturation using canal preparation of GT$^{TM}$ rotary files and Gates Glidden drill showed more apical leakage than the group of lateral condensation using same shaping method with-out statistical significance (p＞0.05).

• Restorative Dentistry and Endodontics
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• 제27권3호
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• pp.277-283
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• 2002

The purpose of this study is to evaluate the two warm gutta-percha filling techniques by measuring the weight changes of resin blocks before and after canal filling in ribbon shaped canal. Simulated ribbon shaped root canals in 30 transparent resin blocks were instrumented to #40 using .06 taper Profile. 15 resin blocks were obturated with gutta-percha using cold lateral condensation. Warm lateral condensation using the Endotec II was then accomplished on the same 15 blocks. Another 15 resin blocks were obturated using the System B. All canals were obturated without sealer. The resin blocks were weighed after canal preparation and after each subsequent obturation, and then weight changes of the resin blocks were calculated The results were as follows. 1. Warm lateral condensation using Endotec II and continuous wave of condensation using System B produced a denser obturation of gutta-percha compared with conventional cold lateral condensation (p<0.01). 2. There was no significant difference between warm lateral condensation and continuous wave condensation. In conclusion, the warm gutta-percha condensation techniques like warm lateral condensation and continuous wave condensation can be expected to bring favorable canal obturation results in ribbon shaped canals.

• 한국전산구조공학회논문집
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• 제13권1호
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• pp.87-95
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• 2000

양단이 단순지지 상태이고, 정현상으로 taper진 부재의 두 고유치(탄성임계하중과 횡방향 고유진동수)를 유한요소법으로 산정하였다. 그 결과로 얻어진 고유치의 계수들을 실무에 종사하는 구조 기술자들이 쉽게 이용할 수 있도록 각각의 경우에 대하여 간단한 대수 방정식으로 표시하였다. 유한요소법으로 구한 고유치 계수값과 대수 방정식에 의한 추정 계수값들의 상관계수는 어느 경우에나 거의 단위치(1)에 가까운 값으로 대수 방정식의 정당성을 뒷받침 하였다. 횡방향 진동수에 미치는 압축하중의 영향도 검토하였다. 이를 위하여 부재에 작용하는 축방향력을 차례로 증가시키면서 여기에 대응하는 진동수를 산정하였다. 그 결과 압축하중비 (P/P/sub cr/)와 진동수 비의 제곱 ((ω/ω/sub 0/)²)의 합은 어느 경우에나 거의 단위치(1)로 나타났다.

• 한국지반공학회논문집
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• 제23권2호
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• pp.61-69
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• 2007

본 연구에서는 현장타설말뚝을 대상으로 지반조건 및 말뚝형태에 따른 수평지지력과 수평거동에 대하여 실험적 분석을 실시하였다. 이를 위해 가압토조실험을 수행하였으며 상대밀도와 지반응력의 변화를 고려하여 원통형과 테이퍼형 말뚝에 대해 재하시험을 수행하였다. 토조실험결과, 수직응력과 수평응력은 모두 말뚝의 수평거동 및 극한수평 지지력에 영향을 나타내는 것으로 관찰되고 있으나, 수평응력의 영향이 보다 더 크게 작용하고 있음을 알 수 있다. 상대밀도 또한 수평거동 및 지지력에 상당한 영향을 미치고 있는 것으로 나타나고 있었다. 수평거동에 대한 말뚝형태의 영향은 지반상태에 따라 다소간의 차이가 보이고 있으나, 전반적으로 지반응렬이나 상대밀도와 같은 지반특성치에 의한 영향에 비해서는 작게 나타나고 있었다. 기존 예측식을 이용한 비교분석 결과, 기존의 예측식에 의해 산정된 결과는 실측된 결과와 상당한 차이를 보이고 있었으며, 이는 지지력 산정시 수평응력의 변화량이 고려되어 있지 않았기 때문임을 알 수 있었다.

• Journal of Advanced Marine Engineering and Technology
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• 제8권1호
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• pp.37-48
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• 1984

For the designing propulsion shafting of ship, shaft diameters are usually calculated according to the Society's rules and other scantlings such as a shaft length, coupling and taper parts, etc., are decided according to calculated diameters. And then, the torsional vibration, the lateral vibration and shaft alignment should be reviewed to check whether the resonance points of torsional or lateral vibration appear within the normal operating speed range and the shaft alignment is reasonable. If the results of calculations are unsatisfactory, this process should be repeated until the final condition is determined and the process of this work takes much time to carry out. To simplify the above tedious processes, authors have developed a computer program to fulfill the above design processes at once. This program takes aim at reducing the manual calculating work associated with the propulsion shafting of ship. To confirm the availability of developed computer program, several propulsion shaftings which are driven by diesel engines, have been analysed. The results calculated by authors developed computer program show comparatively good agreements with those of the actual propulsion shafting.