• Title/Summary/Keyword: maximum adhesion

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New Glass Fiber Reinforced Composite Insulating Material by Reactive Plasma Surface Treatment (반응성 플라즈마 표면 처리기법을 도입한 새로운 유리섬유 강화 복합재료의 개발 및 물성연구)

  • 성열문;하흥주;문상룡;조정수;김규섭
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1994.05a
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    • pp.141-143
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    • 1994
  • One of the Principal problems encountered in the use of filer reinforced composites is to establish an active fiber surface to achieve maximum adhesion between resin and fiber surface. Now, we want to develope new process that will overcome the disadvantage of the chemical coupling agent and achieve maximum adhesion at the interface between resin and fiber by active plasma treatment on the glass fiber surface. In this study. we investigated the effect of plasma treatment on the wettability of glans surface .

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A Design of Prototype 1C2M Railway Vehicle Propulsion Control System Considering Slip Reduction of Traction Motor

  • Chang, Chin-Young;Kim, Jae-Moon;Kim, Yoon-Ho
    • Journal of Electrical Engineering and Technology
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    • v.10 no.1
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    • pp.429-435
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    • 2015
  • This study proposes a re-adhesion algorithm that has stable traction effort for rolling stock slip/slide minimization when deliverable traction decreases by slip. The proposed scheme estimates appropriate reference speed using two encoders for reducing slip and controls traction effort stably and has stable control characteristics for disturbance. The algorithm which uses the maximum adhesive effort by instantaneous estimation of adhesion force stably controls traction effort and gives rolling stock excellent acceleration and deceleration characteristics. And a slip sensing element that can quickly detect slip is used. Load motor and inverter were checked in various slip conditions for creating various line conditions.

A Study on the Properties of the Zn-Cr Alloy Films by Evaporation (진공증착법으로 제조된 Zn-Cr박막의 특성에 관한 연구)

  • Ju, Bong-Hwan;Lee, Gyu-Hwan;Gwon, Sik-Cheol;Baek, Un-Seung
    • 연구논문집
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    • s.23
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    • pp.109-120
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    • 1993
  • A study on corrosion and adhesion properties of evaporated Zn-Cr films were conducted on steel strip by two-source evaporater. Corrosion resistance of Zn-Cr coated steel was evaluated by salt spray test in 5% NaCl. Adhesion property of Zn-Cr films on steel substrate was evaluated by tape test after $180^\circC$ bending. Adhesion was improved with increasing the Cr content and reached the maximum at the Cr content of 6 to 8wt%. Corrosion resistance was enhanced with increasing the Cr content and improved by rolling Zn-Cr coated specimen, as a post-treatment.

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Parametric Study on Test Method for Pull-off Strength of FRP Composite Material used in Strengthening RC Members (FRP 복합체의 콘크리트에 대한 접착강도 시험방법 변수 연구)

  • Choi, Ki-Sun;You, Young-Chan;Lee, Han-Seung;Kim, Keung-Hwan
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05a
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    • pp.222-225
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    • 2006
  • Pull-off test is widely used to evaluate bond performance between concrete and FRP composite. However, reliability of experiment result declines due to many difference between test methods of each national standards. This study analyzed problems of various existing test methods for pull-off test and suggested standardized test method. In addition, since tensile strength of concrete is smaller than bond strength of epoxy resin, maximum bond strength of epoxy resin shall be limited within tensile strength of concrete. Alternative testing method, therefore, which decrease FRP adhesion areas than concrete adhesion areas is suggested to widen test range of bond strength in pull-off test. In the experimental results, bond performance can be estimated up to two times of tensile strength of concrete by reducing FRP adhesion areas by 1/3.

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Effects of substrate type on adhesion strength of cementitious tile adhesive (타일시멘트 접착강도에 미치는 Substrate 종류의 영향)

  • Choi, Nak-Woon;Kim, Sung-Hoon;Kim, Eun-Jeong
    • Proceedings of the Korea Concrete Institute Conference
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    • 2010.05a
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    • pp.325-326
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    • 2010
  • In this study, we prepared three kinds of substrate for the adhesion strength test of cementitious tile adhesive. As a result, the maximum adhesion strength is obtained from the concrete substrate specified in ISO 13007 regardless of curing condition of tile cement specimens.

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Anti-Slip Control and Speed Sensor-less Vector Control of the Railway Vehicle (철도차량의 Anti-Slip 제어 및 속도센서리스 벡터제어)

  • Jho Jeong-Min;Kim Gil-Dong
    • Journal of the Korean Society for Railway
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    • v.8 no.3
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    • pp.216-221
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    • 2005
  • In electric motor coaches, the rolling stocks move by the adhesive effort between rail and driving wheel. Generally, the adhesive effort is defined by the function of both the wright of electric motor coach and the adhesive effort between rails and driving wheel. The characteristics of adhesive effort is strongly affected by the conditions between rails and driving wheel. When the adhesive effort decreases suddenly, the electric motor coach has slip phenomena. This paper proposes a re-adhesion control based on disturbance observer and sensor-less vector control. The numerical simulation and experimental results point out that the proposed re-adhesion control system has the desired driving wheel torque response for the tested bogie system of electric coach. Based on this estimated adhesive effort, the re-adhesion control is performed to obtain the maximum transfer of the tractive effort.

Properties of Blood Compatible Crosslinked Blends of $Pellethene^{(R)}$/Multiblock Polyurethanes Containing Phospholipid Moiety/C-18 Alkyl Chain

  • Yoo, Hye-Jin;Kim, Han-Do
    • Macromolecular Research
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    • v.16 no.7
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    • pp.596-603
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    • 2008
  • To improve the mechanical properties, dimensional stability and blood compatibility, the biomedical material $Pellethene^{(R)}$ was blended with multiblock polyurethane (MPU) containing phospopholipid/long alkyl chain (C-18) at the various MPU contents and crosslinked using dicumyl peroxide as a crosslinking agent. The maximum MPU content for stable $Pellethene^{(R)}$/MPU blended films was approximately 30 wt%. The optimum crosslinking agent content and crosslinking time with respect to the mechanical properties were 4 wt% and 3 h, respectively. The mechanical properties (tensile strength and elongation at break) and water absorption of the crosslinked blend film increased with increasing MPU content. The test of platelet adhesion on the surfaces of the crosslinked blend film showed a decrease in the level of platelet adhesion from 70% to 6% with increasing MPU content from 0 to 30 wt%. These results suggest that the crosslinked $Pellethene^{(R)}$/MPU-30 (MPU content: 30 wt%) sample has strong potential as a novel material for blood compatible material applications.

Fabrication of a Micro-Structure by Modified DXRL Process (수정된 DXRL 공정에 의한 미세구조 제작)

  • Han, Sang-Pil;Jeong, Myung-Yung;Jung, Suk-Won;Kim, Jin-Tae
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.9
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    • pp.1517-1523
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    • 2003
  • Deep X-ray lithography (DXRL), a fabrication method for the production of microstructures with a high aspect ratio, plays an important role in the subsequent electroplanting process. However, secondary radiation is generated during X-ray exposure and damages the resist adhesion to the metal layer. To solve adhesion problems, we modified the conventional DXRL process, changing the sequence of polymer adhesion in DXRL process. With optimized X-ray exposure and development conditions based on a calculated and modified X-ray power spectrum, we fabricated various polymer microstructures and achieved a maximum aspect ratio of 40.

Adhesion characteristics of copper layer fabricated by Sol-Gel process (Sol-Gel법을 이용한 알루미나 기판과 동 피복층간의 접착력 특성)

  • 김동규;이홍로
    • Journal of the Korean institute of surface engineering
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    • v.29 no.3
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    • pp.186-194
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    • 1996
  • In this study, ceramic film was coated by a sol-gel process for increasing the adhesion strength between the substrate and copper layer. TEOS and ATSB were used as starting solution of metallic alkoxide. As a result, amorphous-like diffraction pattern after heat treatment at $1200^{\circ}C$ was obtained using X-ray diffractometer. The more contants of $Al_2O_3$ gave rise to the futher advanced cracks. A maximum adhesion strength of 250gf was measured under the condition of 30 Wt.% $Al_2O_3$, which is 5 times greater than that of uncoated one of the ceramic film.

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Changes of the symptoms following surgical treatment of temporomandibular joint internal derangement with disc adhesion (관절원판 유착을 동반한 악관절 내장증 환자의 수술후 증상의 변화)

  • Kim, Hyung-Gon;Nam, Kwang-Hyun;Park, Kwang-Ho;Huh, Jong-Ki;Kim, Il-Soo;Choi, Hee-Soo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.22 no.3
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    • pp.294-300
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    • 2000
  • Purpose: The aim of this study was to find the clinical characteristics of the patients who had temporomandibular joint internal derangement(ID) with disc adhesion(adhesion group) compared to only disc displacement without disc adhesion, perforation, hyperemia, and so on(ID group). Materials and methods: Thirty seven joints were included in adhesion group and 54 joints in ID group of all 174 patients(174 joints) treated surgically and had been checked periodically over 12 months at TMJ clinic of Yongdong Severance Hospital, Yonsei University, between 1992 and 1997. Mouth opening range, pain during mouth opening and biting, headache, neck/shoulder pain and TMJ sound were checked his/her every visit before and after surgery. Results: The maximum mouth opening was improved significantly after postoperative 3 months in two groups(p<0.01), but adhesion group was less improved. Pain during mouth opening was improved significantly over 3 months after surgery in adhesion group(p<0.01), but in ID group 1 month after surgery. Biting pain was improved and maintained it after surgery and not significant difference between two groups. Headache and neck/shoulder pain were much improved after surgery(p<0.01), but slight relapse was found in adhesion group after 12 months. TMJ sound was more found in adhesion group after 1 month(p<0.05), but after 3 months, no significant difference was found between two groups. Conclusions: The postoperative results of adhesion group were worse than ID group. Therefore, it is considered more carefully to diagnose and treat in cases of internal derangement with adhesion.

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