• 제목/요약/키워드: pull

검색결과 2,033건 처리시간 0.034초

돌리를 이용한 도막 부착력 시험의 영향 인자에 관한 연구 (A study on affecting factors by using dolly in coating adhesion test)

  • 백윤호;손성모;박충서
    • Corrosion Science and Technology
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    • 제13권5호
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    • pp.186-194
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    • 2014
  • Establishment of adhesion strength measurement procedure for marine epoxy coatings was conducted in order to ensure reliability of the test results. It was found that (1) the increase in thickness of the substrates would induce increase of pull-off strength. Especially, the increase in adhesion strength with the substrate thickness increment was attributed to the transition of stress mode to the pure tensile mode excluding bending effect. (2) The longer curing time, the higher pull-off strength. It may be due to higher cross-linking density of the coating (3) The pull-off strength increases as coating thickness increases due to the diminishment of bending effect (4) The longer drying time after water immersion, the higher pull-off strength. It may be due to the evaporation of water molecule at the coating-substrate interface.

멀티채널 소비상황에서 쇼핑행동 전환에 관한 연구 (A Study on the Transformation of Shopping Behavior under Multi-Channel Consumption Environment)

  • 권재국;박병권
    • 한국산업정보학회논문지
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    • 제25권3호
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    • pp.61-82
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    • 2020
  • 본 연구는 멀티채널 환경 내에서 소비자의 쇼루밍에서 웹루밍으로의 쇼핑 행동 전환에 대한 연구로 밀고 당기기 이주 (Push-pull-mooring: PPM) 이론을 적용하였다. 웹루밍 의도에 영향을 미치는 변수로는 푸쉬 효과 (Push effect), 풀 효과 (Pull effect), 그리고 계류 효과 (Mooring effect)로 설정하고, 쇼루밍의 실용적 쇼핑가치의 결핍을 푸쉬 효과로, 웹루밍의 경험적 쇼핑가치를 풀 효과로, 그리고 쇼루밍 락인을 계류 효과로 개념화하였으며, 각각에 영향을 미치는 선행변수들을 문헌연구를 통해 도출하고 연구모형을 설계하였다. 276부의 설문을 대상으로 실증분석을 실시하였으며, 구조방정식 모형을 검증한 결과, 쇼루밍의 실용적 쇼핑가치 결핍과 웹루밍의 경험적 쇼핑가치는 웹루밍 의도에 긍정적인 영향을 미치며, 쇼루밍 계류는 웹루밍 의도에 부정적 영향을 미친다는 것이 확인되었다.

역도 인상동작의 운동학적 분석 (A Kinematic Analysis of Snatch Technique in Weight-Lifting)

  • 문영진;송주호;김지섭
    • 한국운동역학회지
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    • 제14권2호
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    • pp.41-55
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    • 2004
  • This study analyzed snatch technique in weight-lifting performed by female gold, silver, and copper medalists at the 75kg level in the 2002 Pusan Asian Games and obtained the following conclusions. 1. KSH used more extensor in the waist than those in ankles, knees, or hip joints during the second pull, So further training is required to manifest both each of joints and waist extensor effectively and thus for the line from shoulders through barbell to hip joints to form a smooth vertical pattern. 2. Contrary to those in other countries, Korean athlete KSH tended to be swift in starting but slow in the second pull section, showing less effectiveness in movement during the second pull; therefore, they must try to exert a swift movement in lockout. 3. KSH showed slowdown in the speed, which was a factor interfering with performance during second pull, despite the great maximum speed of moving barbell. It is important to use barbell sufficiently not to reduce the speed of vertical movement but rather to keep the speed increasing. 4. KSH, who kept doing inefficient movements such as failure to perform swift lockout after lifting the heel at the maximum angle of lower limbs, needs to reduce this meaningless extension of ankles, knees, or hip joints to exert energy effectively.

히르슈슈프룽병의 일차성 복강경 보조 Endorectal Pull-Through 술식의 임상적 고찰 (Primary Laparoscopic-Assisted Endorectal Pull-Through for Hirschsprung's Disease)

  • 박병순;설지영
    • Advances in pediatric surgery
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    • 제19권2호
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    • pp.130-139
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    • 2013
  • The application of laparoscopic techniques for the surgical management of Hirschsprung's disease is the recent trend. We described the surgical technique and postoperative long-term outcomes of the one-stage, laparoscopic-assiseted endorectal pull-through operation for Hirschsprung's disease. The technique uses three to four small abdominal ports. Laparoscopic mobilization of the sigmoid colon and rectum is performed and marginal artery-preserving colon pedicle is prepared. The rectal mobilization is performed using a transanal endorectal sleeve technique. The anastomosis is performed 0.5~1 cm above the dentate line. The age at surgery ranged from 6 days to 4 years. The average operative time was 144 minutes. Almost all of the patients passed stool and flatus within 36 hours of surgery. The average hospital stay after surgery was 6.5 days. Among 42 patients, 32 patients older than 3 years old were evaluated for function on defecation. All 32 patients have been continent, of those who needed laxatives were 11 (34.3%) due to constipation and overflow incontinence. Four children (12.5%) have remained dependent on laxatives. Laparoscopic-assisted endorectal pull-through operation for Hirschsprung's disease appears to be safe, provides the less pain, shorter time to full feeding, shorter hospital stay, and excellent cosmetic outcomes. Helping patients and parents ensure the quality of life, they should be provided with counseling, education, and longer-term follow-up care.

간편 시행쐐기법을 이용한 스파이럴 파이프 네일링 시스템의 안정해석 및 적용성에 관한 연구 (A Study on Application and Stability Analysis of Spiral Pipe Nailing System Using Simplified Trial Wedge Method)

  • 김홍택;박시삼;박성철;정성필
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2004년도 춘계학술발표회
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    • pp.651-658
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    • 2004
  • In this study, we introduced the spiral pipe nailing system (refer as SPN system) with self drilling method, can apply to ground which is hard to keep shape of bore hole, and performed limit equilibrium analysis with simplilied trial wedge method while length ratio and bond ratio were altered to evaluate slope stability considered of tensile strength and bending stiffness. A newly soil nailing system named as the SPN system is respected to reduce displacement of nail and increase global slope stability. And effects of various factors related to the design of the SPN system, such as the type of drilling method and the bit, are examined throughout a series of the displacement-controlled field pull-out tests. 6 displacement-controlled field pull-out tests are performed in the present study and the volume of grouting arc also evaluated based on the measurements. In addition, short-term characteristics of pull-out deformations of the newly proposed SPN system are analyzed and compared with those of the general soil nailing system by carrying out the displacement-controlled field pull-out tests.

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유한요소해석을 이용한 푸쉬-풀형 고출력 초음파 트랜스듀서 설계 (Design of a Push-Pull Type High Power Ultrasonic Transducer by using the PEM)

  • 윤양기;강국진;노용래
    • 한국음향학회지
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    • 제19권4호
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    • pp.107-114
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    • 2000
  • 기존의 Push-Pull 트랜스듀서보다 간단한 구조를 가지며 출력을 한층 더 높이기 위해서 실린더 중앙에 구동부를 둔 새로운 구조의 Push-Pull 트랜스듀서를 설계하고자 한다. 유한 요소 상용 패키지인 ANSYS를 이용하여 트랜스듀서 모델을 구성한 후, 각종 구조 변수들, 즉, 길이, 반경, Endcap Edge 형상등의 변화에 대한 음압의 변화경향을 조사하여 최대 음압을 구현하기 위한 최적 길이, 반경, Endcap Edge 형상을 설정하였다. 기존 트랜스듀서 보다 구조적으로 더 간단하면서도 더 큰 음압을 구현할 수 있는 새로운 구조의 고출력 트랜스듀서를 개발하였고, 그 성능을 기존 트랜스듀서의 성능과 비교 평가함으로써 개발된 트랜스듀서의 우수성을 입증하였다.

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전력선 통신을 이용한 풀 코드 스위치의 동작위치 인식 시스템에 대한 연구 (A Study on Operating Position Sensing System of Pull Cord Switches Using Power Line Communication)

  • 최남섭;이범
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2003년도 추계종합학술대회
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    • pp.745-748
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    • 2003
  • 본 논문에서는 각종 산업 현장의 라인에 긴급 정지 장치로 병설되는 풀 코드 스위치의 동작위치를 판별하는 시스템에 대하여 다룬다. 특히, 된 논문에서는 전력선 통신 기술을 사용하여 복잡한 케이블 포설 없이도 기존의 2선만을 사용하여 동작된 풀 코드 스위치의 위치를 인식하는 방법을 제시한다. 또한 전력선 통신 IC의 제어 기능을 사용하여 스위치 제어 인식장치에서 각 스위치를 리셋하는 신호를 전송할 수 있도록 구성한다. 끝으로, 논문에서는 제안된 전력선 방식의 풀 코드 스위치 동작위치 인식장치를 제작하고 전력선을 통하여 전달된 신호 및 반응시간 관찰함으로써 풀 코드 스위치의 위치인식 시스템으로 실제로 적용이 가능함을 확인하였다.

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나선형 앵커의 실내인발시험을 이용한 무리효과 평가기법 (The Method of Estimating Group Effect with Small Pull-out Tests of Screw Anchors)

  • 박시삼;이형규
    • 한국지반공학회논문집
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    • 제21권10호
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    • pp.123-131
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    • 2005
  • 본 연구에서는 양압력을 받는 기초구조물의 보강공법으로 앵커를 시공할 경우, 이에 대한 파괴메카니즘 및 안정해석법의 개발에 기초적인 자료를 제공하기 위해 나선형 앵커에 대한 실내인발시험 및 유한요소해석을 수행하였다. 실내인발시험은 강우시 지하수위 상승으로 인해 기초구조물에 양압력이 작용하는 경우를 고려하기 위해 포화사질토 내에서의 하중-변위특성을 분석한 후, 이를 건조시의 경우 등에 대해 유한요소 해석결과와 비교${\cdot}$분석하였으며, 앵커의 극한인발저항력에 미치는 영향인자 및 앵커의 인발에 따른 거동특성 등을 평가하였다. 또한, 군형태 앵커의 설치간격을 변화시켜가면서 하중-인발변위 특성을 비교한 후, 나선형 앵커의 무리효과에 의한 간섭영향 요인을 분석하였다.

Pull-in과 release 전압차 감소용 돌기구조를 갖는 비틀림형 초소형 기계적 스위칭 소자 (Torsional Micromechanical Switching Element Including Bumps for Reducing the Voltage Difference Between Pull-in and Release)

  • 하종민;한승오;박정호
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제50권9호
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    • pp.471-475
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    • 2001
  • ln this paper, a micromachined micromechanical switch is presented. The presented switch is operated in the vertical direction to the substrate by an electrostatic force between two parallel plates. The moving plate is pulled down to connect the bumps of the bias node$(V_{DD}/ or GND)$ to the bumps of the output node when a oltage difference exists between the moving plate and the input plate. The switch was designed to operate at a low switching voltage$(\risingdotseq5V)$ by including a large-area, narrow-gap, parallel plate capacitor A theoretical analysis of the designed switch was performed in order to determine its geometry fitting the desired pull-in voltage and release voltage. The designed switch was fabricated by surface micromachining combined with Ni electroplating. From the experimental results of the fabricated switch, its pull-in voltage came Out to be less than 5V and the measured maximum allowable current was 150mA. The measured average ON-state resistance was about 8$\Omega$, and the OFF-state resistance was too high to be measured with digital multimeter.

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Using scratch test to evaluate cohesive bond strength of Mo composite coating

  • Koiprasert, Hathaipat;Thaiwatthana, Sirinee;Sheppard, Panadda
    • International Journal of Advanced Culture Technology
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    • 제3권2호
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    • pp.34-41
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    • 2015
  • Bonding strength of a thermal sprayed coating is difficult to measure using a conventional pull-off test method. Scratch test is a potential alternative testing method. An adhesive and a cohesive bond strength of the coating can be measured by the pull-off test while the scratch test performed on the cross-section of the thermal sprayed coating can only demonstrate the cohesive bond strength of the coating. Nevertheless, it is still beneficial to perform the scratch testing on the cross-section of the coating for the sake of comparison thus providing an alternative to the pull-off test. The scratch test method can reduce testing time and cost in the long run due to a significant cost reduction in consumables and energy and time saving from the curing step of the glue used in the pull-off test. This research investigates the possibility of using the scratch test to measure the cohesive bond strength of Mo/NiCrBSi composite coating. The results from the pull-off test and the scratch test indicate that the cohesive bond strengths of the Mo composite coating show similar trend and that the cohesive bond strength are increased when increasing NiCrBSi content.