• Journal of Welding and Joining
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• 제19권3호
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• pp.342-347
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• 2001

Recently, adhesive-bonding technique is wifely used in manufacturing structures. Stress and strain analysis of joints are essential to design adhesive-bonded joints structure. The single-lap adhesive joint is the design dominating the range of adhesive joints. In this study, single-lap specimens with different joint dimensions were used for the tensile-shear test and finite element calculation in of order to investigate the effect of overlap length and adhesive-bonding thickness on adhesive strength and stress distribution of the joints. Consequently, it was found that overlap lap size and thickness can be important parameters of structure joints using adhesive bonding, which is effected on adhesive strength.

• Structural Engineering and Mechanics
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• 제62권5호
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• pp.631-642
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• 2017

Accurate actuator tracking plays an important role in real-time hybrid simulation (RTHS) to ensure accurate and reliable experimental results. Frequency-domain evaluation index (FEI) interprets actuator tracking into amplitude and phase errors thus providing a promising tool for quantitative assessment of real-time hybrid simulation results. Previous applications of FEI successfully evaluated actuator tracking over the entire duration of the tests. In this study, FEI with moving window technique is explored to provide post-experiment localized actuator tracking assessment. Both moving window with and without overlap are investigated through computational simulations. The challenge is discussed for Fourier Transform to satisfy both time domain and frequency resolution for selected length of moving window. The required data window length for accuracy is shown to depend on the natural frequency and structural nonlinearity as well as the ground motion input for both moving windows with and without overlap. Moving window without overlap shows better computational efficiency and has potential for future online evaluation. Moving window with overlap however requires much more computational efforts and is more suitable for post-experiment evaluation. Existing RTHS data from Network Earthquake Engineering Simulation (NEES) is utilized to further demonstrate the effectiveness of the proposed approaches. It is demonstrated that with proper window size, FEI with moving window techniques enable accurate localized evaluation of actuator tracking for real-time hybrid simulation.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.897-900
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• 2005

RF linearity of double-gate MOSFETs is investigated using accurate two-dimensional simulations. The linearity has been analyzed using the Talyor series. Transconductance is dominant nonlinear source of CMOS. It is shown that DGMOSFET linearity can be improved by a careful optimization of channel thickness, gate oxide thickness, gate length, overlap length and channel doping concentration. The minimum $P_{IP3}$ data are compared in each case. It is shown that DG-MOSFET linearity can be improved by a careful optimization of channel thickness, gate oxide thickness, gate length, overlap length and channel doping concentration..

• JSTS:Journal of Semiconductor Technology and Science
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• 제11권2호
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• pp.130-133
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• 2011

A comparative study of two capacitance methods to measure the effective channel length in deep-submicron MOSFETs has been made in detail. Since the reduction of the overlap capacitance in the accumulation region is smaller than the addition of the inner fringe capacitance at zero gate voltage, the capacitance method removing the parasitic capacitance in the accumulation region extracts a more accurate effective channel length than the method removing that at zero gate voltage.

• 대한치과기공학회지
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• 제19권1호
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• pp.121-130
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• 1997

This study was aimed to help the construction of naturally dental prosthesis by investigation of the factors affecting on the attrition position and attrition angle of maxillary canines. Therefore 163 complete cast of maxillary and mandibular extracted from the student of K. college were subjected for this study, and result through the study are as follows. 1. None attrite rate of the maxillary canine was 7%, of examined teeth. 2. Throughout mesiodistal attrition of 1) Throughout mesiodistal attrition area of the maxillary canines showed that mesial area and mid area of cusp was more frequence in attrition than distal area of it. 2) Sex, dental arch type, vertical overlap, horizontal overlap, did not affect significantly to throughtout mesiodistal attrition statistically 3. Througout labiolingual attrition area 1) Throughout labiolingual attrition area of the maxillary canines showed that attrition of the from lingual to labioncisal edge was more frequence than it of linguoincisal edge 2) It showed that attrition of the from lingual to labioincisal edge was more frequence when the length of horizontal overlap is shorter, by horizontal overlap 3) The attrition of the from lingual to labioincisal edge in maxillary left canines showed that male was more frequence in attrition than female. 4) Dental arch type, vertical overlap, did not affect signioficantly to labiolingual attrition, statistically. 4. Attrition angle 1) It showed that average attrition angle of the maxillary right canines were $19{\pm}11.02$ dagree, and it of left canines were $18{\pm}11.83$ degree. 2) It showed that famale have a bigger attrition angle than male, by sex. 3) It showed that attrition angle was bigger when the length of horizontal ovelap is bigger, by horizontal overlap.

• 한국항공우주학회지
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• 제37권8호
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• pp.751-758
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• 2009

본 논문에서는 항공기 구조용 탄소 복합재 단일겹침 접착 체결부에서, 파손하중에 영향을 미치는 주요인자들의 효과를 실험으로 연구하였다. 실험을 위해 제작공정 4가지, 겹침 길이 5가지, 모재 두께 4가지에 대한 시편 총 335개를 제작하였다. 예상대로 겹침길이가 감소할수록, 모재두께가 증가할수록 파손강도가 높아지는 것을 확인하였다. 그러나 제작공정의 측면에서는, 접착제가 없는 일체성형 시편과 이차접착 시편의 강도가 동시접착이나 접착제를 사용한 일체성형 시편에서보다 높은 파손강도를 보이는 흥미로운 사실을 발견하였다. 특히 이차접착 시편의 강도가 일체성형 시편의 강도와 유사하거나 더 높은 현상을 발견하였는데, 이는 접착제의 강도가 모재의 층간강도보다 높거나 최소한 비슷한 수준임을 의미하는 것으로 볼 수 있다.

• Composites Research
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• 제20권5호
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• pp.34-42
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• 2007

본 논문에서는 탄소 복합재와 알루미늄으로 구성된 이종재료 단일겹침 접착 체결부에서, 파손하중에 영향을 미치는 주요인자들의 효과를 실험적으로 연구하였다. 실험을 위해 접착압력 4가지(2, 3, 4, 6기압), 겹침길이 6가지(15, 20, 25, 30, 35, 40 mm), 모재 두께 2가지(1.58, 3.01 mm)에 대한 시편 총 66개를 제작하였다. 실험 결과 접착제 FM73에 대해 제작사에서 제시한 접착압력은 약 3기압이었지만 본 연구에서 사용한 이종재료 접착의 경우, 최소 4기압 이상의 접착압력이 필요함을 확인하였다. 겹침길이를 증가시킬 경우 파손하중이 증가하지만 접착부의 폭과 길이의 비가 1을 넘어갈 경우 접착강도 즉 단위 접착면적당의 파손하중의 증가는 크지 않았다. 모재의 두께도 접착부 파손하중 및 강도에 큰 영향을 미쳤으며 모재의 두께가 약 2배로 증가할 때 접착강도는 $12{\sim}32%$까지 증가하였다. 접착부의 파손은 대부분 복합재 모재의 층간분리 형태로 발생하였으며, 접착압력이 높아질수록, 접착길이가 길어질수록 층간분리가 발생하는 위치가 적층판 내부로 깊게 확대되는 경향이 있다.

• 한국자동차공학회논문집
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• 제6권1호
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• pp.143-150
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• 1998

The evaluation of joint fatigue strength of light weight materials for electrical vehicle body has been performed through single lap joint tests with the design parameters such as joint style, adherend, bonding overlap length and bonding thickness. Fatigue strength was evaluated through 5-Hz, tension-tension, load controlled test with the stress ratio zero value. It is experimentally observed that fatigue strength of joint increases for the increase of overlap length. The combinations of Al-Al and Al-FRP adherends show that fatigue strength of joint is hardly changed for the increase of bonding thickness, but FRP-FRP adherend specimen shows that fatigue strength of joint increases after decreases for the increase of bonding thickness. Al-Al adherend specimen has much higher fatigue length than Al-FRP and FRP-FRP adherend specimens. Riveting at adgesive bonded joint gives little effect on fatigue strength.

• 대한전기학회논문지
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• 제43권6호
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• pp.951-957
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• 1994

We present a new model for the series resistance of inverted-staggered amorphous silicon (a-Si) thin film transistors (TFT's) by employing the current spreading under the source and the drain contacts as well as the space charge limited current model. The calculated results based on our model have been in good agreements with the measured data over a wide range of applied voltage, gate-to-source and gate-to-drain overlap length, channel length, and operating temperature. Our model shows that the contribution of the series resistances to the current-voltage (I-V) characteristics of the a-Si TFT in the linear regime is more significant at low drain and high gate voltages, for short channel and small overlap length, and at low operating temperature, which have been verified successfully by the experimental measurements.

• 한국지반신소재학회논문집
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• 제17권1호
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• pp.33-43
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• 2018

2열 겹침말뚝벽체는 30m 이상의 대심도에 적용 가능한 고강성의 주열말뚝으로서 동시에 연속성을 확보하여 차수벽이 되는 흙막이 벽체를 목표로 현재 개발 중에 있는 공법이다. 본 연구에서는 그러한 2열 겹침말뚝벽체의 최적 단면을 결정하는데 필요한 기초 데이터를 확보할 목적으로 여러 조건으로 가능한 시공 단면에 대하여 이론적 방법과 수치해석을 통해 각각의 휨 강성 특성을 조사하고, 이를 기존의 전형적인 CIP 및 SPW 단면의 휨 강성과 비교, 분석하였다. 그 결과, 말뚝 간 겹침길이가 커질수록 휨 강성이 감소하나 말뚝 주열수, 즉 1열과 2열 말뚝 간 휨 강성의 현저한 차이에 비해서는 그 차이가 미미한 것으로 나타났고 또한, 2열 겹침말뚝에서 보강재 종류와 말뚝개당 사용 개수가 휨 강성 크기에 미치는 영향은 겹침길이 차이에 따른 영향보다도 작은 것으로 나타났다. 따라서, 벽체의 구조적 성능 관점에서 본다면 2열 겹침말뚝벽체는 말뚝 간 겹침부 크기와 사용 보강재의 종류, 갯수에 크게 상관없이 대심도용 흙막이 벽체로 기존 공법인 CIP나 SPW 등에 비해 월등히 우수한 성능을 갖춘 것으로 파악되었다.