• 제목/요약/키워드: pulling test

검색결과 75건 처리시간 0.02초

상용차의 제동시 쏠림 개선을 위한 조향 연결점 설계 (Steering System Design of Commercial Vehicle for Improving Pulling Phenomenon During Braking)

  • 이창훈;이동욱;이용수;손정현;김광석;유완석
    • 대한기계학회논문집A
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    • 제37권3호
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    • pp.379-385
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    • 2013
  • 차량의 제동시 쏠림 현상은 크게 타이어에 의한 원인과 현가시스템, 조향시스템 등의 차량구조의 이유로 발생한다. 그 중 차량구조의 원인은 드래그링크 방식의 조향시스템과 판스프링 형태의 현가 스프링 때문으로 볼 수 있다. 본 연구에서는 차량동역학 해석 프로그램인 ADAMS/CAR 를 사용하여 제동시 쏠림의 발생 원인에 대해 분석하였다. 제동시 드래그링크와 판스프링의 거동을 확인하고 그로 인해 발생하는 쏠림을 최소화 시키기 위해 최적화 프로그램인 Visual DOC 를 사용하여 쏠림을 감소시키기 위한 조향 연결점의 위치를 결정하였다. 설계 변경된 차량의 K&C (Kinematic & Compliance) Test 시뮬레이션을 통해서 다른 특성에 미치는 영향이 없음을 보였고, 전차량 제동시뮬레이션을 통해 제동시 쏠림이 감소함을 확인하였다.

Quantification of the tug-back by measuring the pulling force and micro computed tomographic evaluation

  • Jeon, Su-Jin;Moon, Young-Mi;Seo, Min-Seock
    • Restorative Dentistry and Endodontics
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    • 제42권4호
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    • pp.273-281
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    • 2017
  • Objectives: The aims of this study were to quantify tug-back by measuring the pulling force and investigate the correlation of clinical tug-back pulling force with in vitro gutta-percha (GP) cone adaptation score using micro-computed tomography (${\mu}CT$). Materials and Methods: Twenty-eight roots from human single-rooted teeth were divided into 2 groups. In the ProTaper Next (PTN) group, root canals were prepared with PTN, and in the ProFile (PF) group, root canals were prepared using PF (n = 14). The degree of tug-back was scored after selecting taper-matched GP cones. A novel method using a spring balance was designed to quantify the tug-back by measuring the pulling force. The correlation between tug-back scores, pulling force, and percentage of the gutta-percha occupied area (pGPOA) within apical 3 mm was investigated using ${\mu}CT$. The data were analyzed using Pearson's correlation analysis, one-way analysis of variance (ANOVA) and Tukey's test. Results: Specimens with a strong tug-back had a mean pulling force of 1.24 N (range, 0.15-1.70 N). This study showed a positive correlation between tug-back score, pulling force, and pGPOA. However, there was no significant difference in these factors between the PTN and PF groups. Regardless of the groups, pGPOA and pulling force were significantly higher in the specimens with a higher tug-back score (p < 0.05). Conclusions: The degree of subjective tug-back was a definitive determinant for master cone adaptation in the root canal. The use of the tug-back scoring system and pulling force allows the interpretation of subjective tug-back in a more objective and quantitative manner.

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.

깊은 홈 및 절단가공용 드로우어웨이식 초경공구 시스템의 설계에 관한 연구 (A Study on the Design of Throw-away Cutting Tool System for Deep Grooving or Cut-off Machining)

  • 김형철;이우영;남궁석
    • 한국정밀공학회지
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    • 제13권1호
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    • pp.123-130
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    • 1996
  • The procedure on the design of a new tungsten cabide throw-away cutting tool system for deep grooving or cut-off machining is suggested. For relieving the maximum stress level at the corner radius of the blade holder, the finite element method is used. Also the pulling test device is proposed for measuring the holding force of the insert between the blade holder and the insert considering the materials in contact and configuration parameters of the holder.

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벼수확 논에서 트랙터견인형 액비살포기의 소요견인력 측정에 관한 연구 (A Study on the Requirement of Tractor Pulling Force of Slurry Manure Spreader for the Utilization in Paddy Field)

  • 오인환;김기덕
    • 한국축산시설환경학회지
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    • 제8권2호
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    • pp.99-106
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    • 2002
  • This study was conducted to improve utilization efficiency of slurry and choose a suitable type of tractor power which can be attached by manure spreader in the paddy field. In the paddy field, the pulling force for the spreader was measured by using a measurement system installed between tractors with and without the spreader. The soil moisture contents at the 0${\sim}$10cm and 10${\sim}$20cm depth of test soil(SiCL) were 28.45% d.b. and 23.47% d.b., respectively in average while Cone Index at l0cm and 15cm depth were 14.5kPa and 16.2kPa, respectively. It was impossible to measure the soil moisture contents and Cone Index below 20cm depth of the soil because the hardness of the soil increased greatly. Thereafter, hard pan of the sampled soil was found at 15${\sim}$20cm depth. While the required power only for the dragged tractor was found to be 3.44kW in the test field, the required pulling powers of tractor considering the pumping were 8.48${\sim}$12.48kW, 12.19${\sim}$16.19kW, 16.96${\sim}$20.96kW, respectively for 2 tons, 3 tons, and 4 tons of tank capacity. As the tank capacity increased, the sinkage of soil were also increased to 7cm, l0cm, and 12cm, respectively for the tractors with 2 tons, 3 tons and 4 tons of tank capacity. Considering about 60% of pulling efficiency of tractor, a tractor which had lower than 25.74kW of pulling power was suitable to pull the spreader and spread the slurry simultaneously for manure spreader with 2 tons of tank capacity. 29.42kW${\sim}$36.78kW of pulling power was found to be optimum for the tractor with 3 tons of tank capacity while over 40.45kW for 4 tons of tank capacity.

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풍화암에 시공된 부력저항 앵커의 거동특성 (Characteristics of Anchor Behavior Resisting Buoyancy Forces in the Weathered Rock)

  • 유남재;이근착;정길수;박병수
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2005년도 지반공학 공동 학술발표회
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    • pp.698-705
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    • 2005
  • This study contains actual scaled site experiments on mediation factors affecting ultimate pulling force of the buoyancy resisting anchor which is installed underground water level suffering buoyancy force and breaking mechanism. Site buoyancy test selected the buoyancy acting site where acting buoyancy to the station structure since the stream and reservoir is neighboured to the vicinity ground and executed site experiments leading to variation of anchoring length, drilling diameter and tendon diameter at the weathered rock ground. The test result showed that pulling force getting increased more and more proportionate to increase of anchoring length, drilling diameter and tendon diameter, and as a result of analysis for correlations between anchoring length-ultimate limited load and drilling diameter-ultimate load (on the basis of 254mm settlement), modulus of correlation showed very high relation 0.9 and 0.99 respectively and correlation formular showed the limited load is increasing proportionate to cubic meters of anchoring length as well as the ultimate load proportionate to alignment of drilling diameter. It is also showed that limited load increased about 42.5% from 392kN to 559kN as a result of change the tendon diameter to 36mm and 50mm.

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침치료를 시행한 위증(근이양증(筋異養症)) 환자 치험 1례 (A clinical report on one case of muscular dystrophy)

  • 이장원;김철한;황의형;김정연
    • 대한추나의학회지
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    • 제6권1호
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    • pp.177-187
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    • 2005
  • Objective : We want to investigate the patient who has a muscular dystrophy how much muscular strength is improved and general conditions are changed after applying Sa-am acupuncture. Method : The patient who has a muscular dystrophy was evaluated by AchR-ab, VAS, pulling power test after applying Sa-am acupuncture.

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경사진 바인더면의 드로우비드력을 측정하기 위한 모의실험장치 (An Angle-Binder Drawbead Simulator for Measuring Drawbead Forces on Inclined Binder Surface)

  • 양우호;최광용
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2009년도 춘계학술대회 논문집
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    • pp.180-184
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    • 2009
  • A novel set of experimental test tooling for measuring pulling and holding forces for drawbeads on binders inclined at a wide range of angles is introduced. A mechanical design featuring a single load cell, a male-female draw bead set, translation and rotation degrees of freedom, and a screw-driven clamping system has been incorporated into a standard tensile test machine. On a real time basis, restraining and holding force data with respect to draw-in displacement may be directly downloaded into a PC for data processing. The proposed experimental system represents a significant breakthrough in drawbead simulation technology due to its relatively low cost, clever design, and versatility. The system is shown to yield excellent experimental data suitable for verifying theory and numerical model predictions.

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콘크리트 파일앵커의 설치 매니퓨레이터의 개발을 위한 모형실험에 관한 연구 (Model Test for the Development of Installing Manipulator of Concrete Pile Anchor)

  • 윤길수;김호상
    • 한국해양공학회지
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    • 제18권1호
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    • pp.47-52
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    • 2004
  • Greater holding force of an anchor is required for maintaining the position of a larger floating structure. According to the series of model tests of pile anchors with movable fluke, the square type pile anchor, with fluke, showed more than 6 times of the uplift pulling force, compared to the same type pile anchor, without fluke. This uplift force is 100 times its weight. When the water depth is more than 40m, It is difficult to install the pile anchor. For a convenient installation method, a type of manipulator is proposed for the separation of a weight and buoyancy controller, using TRIZ.