• 제목/요약/키워드: Pulling Force

검색결과 94건 처리시간 0.03초

열변형을 고려한 열경화성수지 복합재료의 펄트루젼 공정에 관한연구 (A Study on the Pultrusion Process of Thermosetting Composites Considering Thermally induced Deformation)

  • 김대환;이우일
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 1999년도 춘계학술발표대회 논문집
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    • pp.103-108
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    • 1999
  • A synthesized model of pultrusion process considering thermally induced deformatiion was established. The model was composed of liquid resin flow model thermo-chemical analysis and linear elastic analysis. in order to verify the above-mentioned models several experiments were performed. A laboratory scale pultrusion line was established and glass/polyester composites were fabricated. the experimental results were compared with the calculated ones. The model successfully could estimate degree of cure pulling force and amount of process-induced deformation.

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Effects of 6-Week Self-Scapular Upward Rotation Exercise on Downward Pulling Tension in Subjects With Scapular Downward Rotation Syndrome

  • Ha, Sung-Min;Kwon, Oh-Yun;Park, Kyue-Nam
    • 한국전문물리치료학회지
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    • 제19권4호
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    • pp.32-37
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    • 2012
  • The purpose of this study was to investigate the quantitative data of downward pulling tension in subjects with scapular downward rotation syndrome (SDRS) before and after 6-week self scapular upward rotation exercise (SURE) program. Eleven subjects with bilateral SDRS. The downward pulling tension(DPT) was measured digital tension-meter. The tension force data were collected using a surface electromyography before and after a 6-week self-scapular SURE program. The significance of difference between pre- and post-program was assessed using a paired t-test, with the level of significance set at ${\alpha}$=.05. The results showed that significant differences between pre- and post-SURE program were found for DPT (p<.05). These findings suggest that 6-week self SURE program is effective for reducing DPT in subjects with SDRS. Additionally, our DPT measurement can be useful for maintaining shoulder position and providing quantitative data between pre- and post-SURE program during passive correction of scapular position test.

현장 인발시험을 통한 수목의 한계 전도모멘트 검토 (Investigation of Critical Breaking Moment through Field Tree-Pulling Test)

  • 임동균;김원;최성욱;김용전
    • 대한토목학회논문집
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    • 제31권4B호
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    • pp.323-332
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    • 2011
  • 하천에서 수목의 관리를 위해서는 수목이 홍수에 미치는 영향이나 생태적 특성을 고려하여 대책을 수립하여야 한다. 수목에 의한 수리학적 영향은 통수능 감소와 유수력에 의한 전도로 인한 하류 하천시설물의 기능 저해이다. 현장 인발시험은 수목이 전도될 때의 최대 저항력을 측정하여, 하천 내의 수목이 외력에 저항하는 정도를 파악하기 위해 시행하였다. 수목의 전도모멘트를 파악하기 위한 인자는 수목의 외형적 특성인 수종, 흉고직경, 수고 등이며, 본 연구에서는 전도모멘트와 흉고 직경의 상관관계를 이용하였다. 수목의 한계 전도모멘트는 흉고직경 4.9-32.8 cm의 관목과 교목 100주를 바탕으로 검토되었다. 교목과 관목을 함께 고려할 경우에는 흉고직경과 한계 전도모멘트의 상관관계를 도출하기 어려웠다. 그러나 교목만을 고려할 경우에는 흉고직경과 한계 전도모멘트 사이에 일정한 상관관계가 있음을 확인하였다.

원심모형실험을 이용한 모래지반에 관입된 계류선 거동 평가 (Evaluation of Behaviors on Mooring Line Embedded in Sand Using Centrifuge Test)

  • 이훈용;김수린;김재현;김동수;추연욱;권오순
    • 한국해양공학회지
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    • 제28권1호
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    • pp.47-54
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    • 2014
  • When an anchor penetrates and is installed under a seabed, a portion of the mooring line connected to the anchor is also embedded under the seabed. This embedded mooring line affects the capacity of the anchor in two ways. First, the frictional resistance that occurs between the mooring line and the seabed reduces the pulling force acting on the anchor. Second, the embedded part of the mooring line forms a reverse catenary shape due to the bearing resistance of the soil, so that an inclined pulling force is applied to the anchor. To evaluate the mooring line's effect on the capacity of an anchor in sand, centrifuge model tests were performed using two relative sand densities of 76% and 51% while changing the anchor depths. The test results showed that the load is reduced much more in deep and dense sand, and the inclination angle of the load is lower in shallow and loose sand.

삼각트랙을 구비한 외벽 등반로봇 플랫폼의 안정성 및 이동성 향상을 위한 토크 분배 알고리즘 개발 (Development of a Torque Distribution Algorithm for Improving Stability and Mobility of the Wall-climbing Robot Platform (ROPE RIDE) Equipped with Triangular Track Wheels)

  • 조선미;서근찬;김태균;김종원;김화수
    • 한국정밀공학회지
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    • 제30권7호
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    • pp.725-732
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    • 2013
  • This paper presents a torque distribution algorithm for improving the stability and mobility of a wall-climbing robot platform. During ascent, the pitch moment caused by the payload or external disturbances separates the robot's triangular tracks from the wall, significantly deteriorating its stability. Moreover, the reaction forces stemming from the increase in the pulling force may degrade the robot's mobility. Thus, it is very important to minimize the reaction forces acting on the triangular tracks, as well as the fluctuations in the pulling force, during the climb. Through dynamic modeling of the proposed robot platform, we demonstrated the dependence of the robot's stability and mobility on the torque distribution of the triangular tracks. Extensive simulations using different climbing speeds were used to significantly improve the stability and mobility of the proposed robot platform.

박판성형 마찰거동에 미치는 블랭크 홀딩력의 영향 (Effects of Blank Holding Force on Friction Behavior in Sheet Metal Forming)

  • 심진우;금영탁
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2007년도 춘계학술대회 논문집
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    • pp.394-396
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    • 2007
  • In this study, in order to see effect of the blank holding force on the friction behavior in the sheet metal forming, a sheet metal friction tester is designed and manufactured, which can measure friction forces in various forming conditions, such are lubrication, die roughness, drawing speed, radius of die corner, blank holding force, etc., and performed the friction test in which friction coefficients in various blank holding forces and pulling speeds are calculated using Coulomb's friction law. The friction test reveals that friction coefficient decreases maximum 30% as the blank holding force and the drawing speed are increased to 2.5kN and 1500mm/min, respectively.

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박판성형 마찰거동에 미치는 블랭크 홀딩력의 영향 (Effects of Blank Holding Force on the Friction Behavior in Sheet Metal Forming)

  • 심진우;금영탁
    • 소성∙가공
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    • 제16권5호통권95호
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    • pp.381-385
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    • 2007
  • In order to examine the effect of the blank holding force on the friction behavior in the sheet metal forming, a sheet metal friction tester is designed and manufactured, which can measure friction forces in various forming conditions such as lubrication, die roughness, drawing speed, radius of die corner, blank holding force, etc., and the friction tests are performed, in which friction coefficients in various blank holding forces and pulling speeds are calculated using Coulomb's friction law. The friction test reveals that friction coefficient decreases as the blank holding force, the drawing speed and lubricant viscosity increase together or individually.

A Force/Moment Direction Sensor and Its Application in Intuitive Robot Teaching Task

  • Park, Myoung-Hwan;Kim, Sung-Joo
    • Transactions on Control, Automation and Systems Engineering
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    • 제3권4호
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    • pp.236-241
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    • 2001
  • Teach pendant is the most widely used means of robot teaching at present. Despite the difficulties of using the motion command buttons on the teach pendant, it is an economical, robust, and effective device for robot teaching task. This paper presents the development of a force/moment direction sensor named COSMO that can improve the teach pendant based robot teaching. Robot teaching experiment of a six axis commercial robot using the sensor is described where operator holds the sensor with a hand, and move the robot by pushing, pulling, and twisting the sensor in the direction of the desired motion. No prior knowledge of the coordinate system is required. The function of the COSMO sensor is to detect the presence f force and moment along the principal axes of the sensor coordinate system. The transducer used in the sensor is micro-switch, and this intuitive robot teaching can be implemented at a very low cost.

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