• 한국컴퓨터그래픽스학회논문지
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• 제25권1호
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• pp.1-11
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• 2019

책상 위에 놓인 젖은 옷감을 움직이기 위해서는 마른 옷감을 움직일 때와 비교하여 더 많은 힘이 필요하게 되는데, 그 이유는 젖은 옷감과 책상의 표면 사이의 위치한 유체가 접착력을 만들어내기 때문이다. 본 논문은 젖은 옷감이 물체의 표면에 달라 붙는 현상에 집중하여 젖은 옷감을 표현한다. 접착력을 계산하기 위해서 우리는 섬유 관련 연구 분야에서 실제 실험을 기반으로 모델링한 접착력 모델을 활용하였고, 기존 연구와 다르게 젖은 옷감이 물체와 닿아있는 부분에서도 자연스럽게 주름이 만들어지는 모습을 표현한다. 젖은 옷감이 물체에 달라 붙는 현상과 더불어 젖은 옷감끼리도 서로에게 달라 붙는 현상을 표현함으로써 보다 실제의 젖은 옷감과 유사한 결과를 보인다.

• 대한건축학회논문집:구조계
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• 제34권9호
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• pp.19-26
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• 2018

The focus of this study was centered around 15 common injection type water leakage repair materials (3 different types for each; synthetic polymer, cementitious, acrylic, epoxy, urethane) used in concrete structures of Korea and analyzing their wet surface adhesion performance in accordance to the ISO TS 16774 Test Method for Repair Materials for Water-leakage Cracks in Underground Concrete Structures, Part 4: Test Method for Adhesion on Wet Concrete Surface, and the results of this study was taken to be place under a comparative analysis with the results of the preceeding study on response to substrate movement performance study. The results of this comparative study showed that other than 1 specimen of 1 type of the acrylic and 3 specimens of 1 type of the synthetic polymer type materials, all of the 93% of the specimens used in this study showed stable adhesion on wet substrate surface, and we were able to determine that materials that have proper response properties against substrate movement are highly flexible and have high adhesion properties, but their adhesion properties on wet substrate would change based on their viscosity.

• 한국컴퓨터정보학회논문지
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• 제28권10호
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• pp.77-84
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• 2023

물리 기반 시뮬레이션에서 젖은 머리카락이나 털의 응집력과 뻣뻣함을 시뮬레이션 하는 것은 어려운 문제 중 하나이다. 젖은 머리카락이나 털은 끝부분이 뭉치고 뻣뻣해지는 것이 특징이며, 이는 젖은 동물의 털이나 머리카락에서 볼 수 있는 현상이다. 또한 젖은 머리카락은 고체와 상호작용을 하면 접착력이 발생하지만, 이 문제는 곱슬머리에서 힘의 분산과 균형이 달라지기 때문에 해결하기 어려워진다. 기존 방법에서는 수작업을 통해 젖은 머리를 표현하거나 정적인 헤어스타일로 젖은 곱슬머리 및 털을 표현한다. 그러나 젖은 곱슬머리의 디테일을 묘사하는 방법에 대한 연구는 아직 활발히 연구되지 않았다. 따라서 본 논문에서는 젖은 곱슬머리의 컬 과장, 응집력, 접착력 그리고 강성을 효율적으로 모델링하는 새로운 알고리즘을 제안한다. 제안하는 방법은 응집력을 효율적으로 시뮬레이션하고 강성 제약 조건을 곱슬머리 역학과 통합하여 안정적으로 모발의 탄성을 제어한다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
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• pp.330-335
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• 1998

This research was conducted to evaluate the adhesion in tension of the polymer mortars for cement concrete repair. Various polymer types, binder ratios, and wet/dry conditions of the surface were considered in this study. Styrene-butadiene rubber (SBR) and ethylen vinyl acetate (EVA) used for polymer cement mortars. Epoxy resin (EP), and unsaturated polyester resin (UP) were used for polymer mertars. Adhesion in tension for the dry condition of the substrate surface was higher than that for the wet condition of the substrate surface under the same binder ratio. Therefore, in repairing concrete, the dry surface condition was effective on adhesion.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.137-138
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• 2017

The Waterproofing and Anti corrosion materials applied to the water supply facility did not consider environment of water supply facility, thus defects occurred consistently on the site. In this study, it suggests safety adhesion test of wet surface and have a test for safety adhesion performance.

• 로봇학회논문지
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• 제17권3호
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• pp.282-287
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• 2022

High shear adhesion on wet and rough surfaces and tactile feedback of gripping forces are highly important for realizing robotic gripper systems. Here, we propose a bioinspired robotic gripper with highly shear adhesion and sensitive pressure sensor for tactile feedback systems. To achieve them, we fabricated multi-walled carbon nanotube sensing layer on a thin polymeric adhesive layer of polydimethylsiloxane. With densely hexagonal-packed microstructures, the pressure sensor achieved 9 times the sensing property of a sensor without microstructures. We then assembled hexagonal microstructures inspired by the toe pads of a tree frog, giving strong shear adhesion under both dry and wet surfaces such as silicon (42 kPa for dry and ~30 kPa for underwater conditions) without chemical-residues after detachment. Our robotic gripper can prevent damage to weak or smooth surfaces that can be damaged at low pressure through pressure signal feedback suggesting a variety of robotic applications.

• 접착 및 계면
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• 제10권2호
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• pp.84-89
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• 2009

The objective of this research was to investigate the curing behavior and adhesion performance of urea-melamine-formaldehyde (UMF) resin for the four types of UMF-1, UMF-2, UMF-3, and UMF-4 which synthesized by the staged addition of melamine. Also, various network structures of these resin types were discussed based on their different curing behavior and adhesion performance. The curing behavior was evaluated by DMTA and thermal stability was checked by TGA. Adhesion performance was evaluated by dry and wet shear strengths and the pH value of each cured resin was checked to see its effect on the adhesion performance. The results indicated that the UMF-1 resin type by the addition of melamine initially with the urea and formaldehyde at the same F/(U+M) rate showed the lowest thermal stability, rigidity (${\Delta}E^{\prime}$), temperature of tan ${\delta}$ maximum ($T_{tan}\;_{\delta}$), and wet shear strength, and pH value of cured resin. In wet shear strength, however, the UMF-4 resin type appears to be slightly higher than UMF-1 resin type.

• Elastomers and Composites
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• 제54권4호
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• pp.299-307
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• 2019

Rubber friction properties include adhesion friction characteristics of the interface, hysteresis friction characteristics originating from repeated rubber deformations, and cohesion friction characteristics due to wear and tear. Cohesion friction is generally sufficiently small (< 3%) that it can be ignored, whereas adhesion friction has a relatively large contribution of 15%, but has not been investigated thoroughly. Therefore, through an adhesion friction study, the adhesion mechanism was examined and the relationship between friction characteristics and adhesion friction on dry surfaces was derived. The wet grip characteristics of tread rubber are fully described by the hysteresis characteristics of tires, but friction characteristics on dry roads are difficult to determine without adhesion factors. The results presented herein demonstrate that the combination of hysteresis and adhesion properties in the tread rubber sufficiently explained the characteristics of the dry grip. Based on the results of this study, technologies will be developed to determine the key factors governing adhesion friction characteristics and improve dry tire braking performance.

• 접착 및 계면
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• 제14권2호
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• pp.68-74
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• 2013

Acid group을 도입하여 접착 및 그립성이 향상된 casting 폴리우레탄을 합성하였다. 폴리우레탄의 그립 특성 및 접착 특성을 확인하였고, 접촉각 및 인장강도, 기계적 물성 등을 연구하였다. Acid 함량에 따른 특성들을 조사하기 위해 acid 함량별로 경화제를 제조하여 각각의 특성들을 연구하였다. Acid group을 도입함으로써 접착력 및 wet slip이 증가하는 것을 확인할 수 있었으며, 인장강도 및 마모 등 기계적 물성 또한 증가하는 것을 확인할 수 있었다. Acid 함량별로 물성을 측정한 결과 일정한 함량까지 기계적 물성은 증가하며, 일정 함량 이상에서는 기계적 물성 및 접착력이 감소하는 것을 확인할 수 있었다. Wet slip과 접촉각의 경우에는 acid group 도입에 의해 친수성이 증가함으로 acid 함량이 증가할수록 wet slip은 증가하며 접촉각의 경우에는 감소하는 것을 확인할 수 있었다.

• 한국레이저가공학회지
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• 제6권3호
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• pp.29-35
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• 2003

In semiconductor processing, there are two types of particle contaminated onto the wafer, i.e. dry and wet state particles. In order to evaluate the cleaning performance of laser shock wave cleaning method, the removal of 1 m sized alumina particle at different particle conditions from silicon wafer has been carried out by laser-induced shock waves. It was found that the removal efficiency by laser shock cleaning was strongly dependent on the particle condition, i.e. the removal efficiency of dry alumina particle from silicon wafer was around 97％ while the efficiencies of wet alumina particle in DI water and IPA are 35％ and 55％ respectively. From the analysis of adhesion forces between the particle and the silicon substrate, the adhesion force of the wet particle where capillary force is dominant is much larger than that of the dry particle where Van der Waals force is dominant. As a result, it is seen that the particle in wet condition is much more difficult to remove from silicon wafer than the particle in dry condition by using physical cleaning method such as laser shock cleaning.