• Applied Microscopy
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• 제50권
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• pp.13.1-13.7
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• 2020

We examined the morphology of fertilized egg and ultrastructures of fertilized egg envelopes of Ancistrus cirrhosus belong to Loricariidae using light and electron microscopes. The fertilized eggs formed a mass on the spawning place and were yellowish, spherical, non-transparent, demersal, adhesive, and a narrow perivitelline space. But, the adhesiveness of fertilized eggs was disappeared after spawning excluding contact parts. The micropyle with funnel shape was surrounded by 15-19 furrow lines of egg envelope in a spoke-like pattern. The outer surface of egg envelope has smooth side and inner surface of egg envelope was rough with grooves. Also, the total thickness of the fertilized egg envelope was about 32.58 ± 0.85 ㎛ (n = 20), and the fertilized egg envelope consisted of three layers, an outer adhesive electron-dense layer, a middle layer with low electron density and an inner electron-dense layer with grooves in counter structure from other most teleost. Collectively, these morphological characteristics and adhesive property of fertilized egg, and ultrastructures of micropyle, outer surface, and section of fertilized egg envelope are showed species specificity.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 봄 학술발표회논문집(II)
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• pp.613-617
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• 1998

This study deals with the effect on adhesive strength properties of fiber sheet layer and maintenance position of coccrete structure reinforced using epoxy resin carbon and aramit fiber sheet. Properties of epoxy resin adhesive strength of the concrete bridge slab, tunnel and wall etc. reinforced using fiber sheet under many different environment change according to condition of concrete substrate, temperature, moisture, curing, cleaning, and chemical effects and so on. The purpose of this study is that it makes the estimation value of adhesive strength of concrete substrate and fiber sheet reinforcing layer penetrated epoxy resin under high temperature(9$0^{\circ}C$), chemical attack and condition of curing.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2005년도 춘계학술발표대회 개요집
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• pp.262-264
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• 2005

This paper is concerned with a fracture strength study of composite adhesive lap joints. The tests were carried out on specimen joints manufactured hybrid stacked joints such as the polyester and bamboo natural fiber layer. The main objective of the work was to test the fracture strength using hybrid fiber composites with a polyester and bamboo natural fiber layer adjacent to the spew fillet of adhesive bonded joints and hybrid stacked joints. The results are presented using tensile-shear strength graph and finite element analysis. The failure mechanisms are discussed in order to explain that spew fillet at the end of the overlap reduces greatly the adhesive shear and effects the tensile-shear strength in hybrid stacked joints.

• Restorative Dentistry and Endodontics
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• 제33권1호
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• pp.45-53
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• 2008

본 연구는 현재 시판되고 있는 여러 개의 상아질 접착제를 임상 술식에서와 같은 방법으로 사용한 후 열 시효처리를 통해 노화 과정을 재현한 다음 접착 계면의 탄성계수를 측정함으로써 가수분해에 따른 물성변화를 관찰 비교하고자 했다. 발거 한 지 2 주일 이내인 영구 대구치 21 개의 상아질 표면이 노출되도록 삭제하였다. 각각 7개의 치아에 시판되고 있는 3가지 상아질 접착제 (OptiBond FL, Clearfil SE, Xeno III)를 적용한 뒤 광중합 복합 레진(Premisa, Kerr, Orange, CA, USA) 를 1 mm 두께로 쌓아 올렸다. 각 치아를 이등분하여 절반 시편은 100,000회의 열 시효 처리를 가하도록 했다. Nanoindentation test를 통하여 각 시편의 adhesive layer와 hybrid layer의 탄성계수를 측정, 비교하였다. 열시효 처리 후 Xeno III군의 탄성계수가 통계학적으로 유의할 만한 감소를 보였다 (p < 0.05). Hydrophilic monomer를 많이 함유한 one-step self-etch adhesive system은 다른 제품에 비해 가수분해에 취약하여 이에 따른 물성 변화를 보이는 것으로 추정되며, 궁극적으로 수복물의 내구성에 영향을 미칠 것으로 여겨진다.

• Advances in aircraft and spacecraft science
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• 제4권6호
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• pp.679-699
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• 2017

The aim of this study is to perform a finite element analysis of the Von Mises stresses distribution in the adhesive layer and of the J-Integral for a damaged plate repaired by a composite patch. Firstly, we study the effect of the fiber orientation, especially the position of the layers that have orientation angle different of $0^{\circ}$ from the first layer which is in all cases of our study oriented at ($0^{\circ}$) on the J-Integral. Secondly, we evaluate the effects of the mechanical properties of the patch and the use of a hybrid patch on the reduction of stresses distribution and J-Integral. The results show clearly that the stacking sequence for the composite patch must be selected to absorb optimally the stresses from the damaged area and to position the various layers of the composite under the first layer whose fibers orientation will remain in all cases equal to $0^{\circ}$. The use of a hybrid composite reduces significantly the J-Integral and the stresses in both damaged plate and the adhesive layer.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.234-235
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• 2017

The bonding of the asphalt-based waterproof sheet is carried out in such a manner that the sheet and the sheet are adhered together and the lower adhesive layer of one sheet is adhered to the upper film layer of the other sheet, and the asphalt layer and the PE or HDPE film layer are bonded. When the joints are formed in the form of junctions between heterogeneous materials and exposed to the concrete joint movements and other deteriorating factors, the integrity of the joints can deteriorate and problems such as lifting and peeling off of the joints can occur. Therefore, this study was carried out to prevent unstable joint adhesion of the asphalt compound and film layer and to prevent defects in the adhesion between self - adhesive waterproof sheets. The self-adhesive waterproof sheet of this study can maximize bond stability by inducing bond between asphalt compounds during sheet-to-sheet bonding, thereby improving bonding strength.

• 반도체디스플레이기술학회지
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• 제10권1호
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• pp.91-94
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• 2011

This paper presents light transmission efficiency by optical adhesive thickness between MLA and aperture layer and by aperture hole size. The gap between MLA and Aperture layer is adjusted by the shim. The more optical adhesive thickness increases, the better light transmission efficiency increases up to a point. After that, the light transmission efficiency decreases because stray lights cannot transmit through the aperture layer owing to cut-off by aperture layer. And as a result of light transmission efficiency with changing aperture hole size, the light transmission efficiency is proportional to area of aperture hole. The more specified process is made, the better data and sample will be got.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 추계학술대회 논문집
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• pp.771-772
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• 2010

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2003년도 제21회 추계학술대회 논문집
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• pp.230-237
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• 2003

로켓의 신뢰성을 위해서 토출관의 접합계면을 평가하기위한 초음파 시험법을 개발하였다. 본 연구의 주된 목적은 철피와 FRP 사이의 에폭시 접합계면에서 미접착 부위와 미충전 부위를 찾아내는 것이다. 미접착부나 미충전부를 찾아내기 위해서 고주파수 초음파 펄스-에코를 이용하여 철피와 에폭시 접착제 사이의 경계면에서 반사되는 초음파 신호를 측정하였다. 결함이 있는 부위의 gap의 크기를 평가하기 위해서 저주파 초음파를 이용하여 공진이 일어나도록 철피를 가진하였다. 이러한 기법을 이용하여 양산품을 검사하기 위한 자동화 장치를 개발하였다. 검사기법을 검증하기 위해서 초음파 시험을 수행한 토출관을 절단하여 현미경으로 gap을 측정하였다.

• Restorative Dentistry and Endodontics
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• 제24권4호
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• pp.546-553
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• 1999

In Older to evaluate the effectiveness of 'One-bottle dentin adhesive system', the shear bond strengths of two fourth generation dentin adhesive systems and two One-bottle systems to the occlusal dentin of the freshly extracted third molars were measured by the regulation of the ISO TR 11405. The fourth generation dentin adhesive systems used in this study were Scotchbond Multi-Purpose Plus and All-Bond 2, and the One-bottle systems were Single Bond and One-Step. The effects of the thickness of hybrid layer and adhesive layer, the diameter of resin tag and the ratio between the diameter of resin tag and that of dentinal tubule were analyzed as the contributing factors of the shear bond strength of dentin bonding systems from the Scanning Electron Microscopic images. The results were as follows: 1. The shear bond strengths of Scotchbond Multi-Purpose, All-Bond 2, and Single Bond were 16.98${\pm}$3.40 MPa, 15.10${\pm}$2.77 MPa and 15.05${\pm}$3.18 MPa, respectively. There were no statistical differences(p>0.05). 2. But, the shear bond strength of One-Step were significantly lower than those of the other groups (11.81${\pm}$1.95 MPa, p<0.05). 3. The thicknesses of hybrid layer and adhesive layer of One-Step were significantly thinner than those of the other groups(p<0.05). The differences of the diameter of resin tag(p=0.0685) and the ratio between the diameter of resin tag and that of dentinal tubule(p=0.2401) were not significant among all the material groups. 4. The thickness of hybrid layer and adhesive layer might be considered as contributing factors of the she at bond strengths of dentin bonding systems, but the diameter of resin tag and the ratio between the diameter of resin tag and that of dentinal tubule might not.