• Title/Summary/Keyword: Lateral force

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Design, Fabrication and Test of Piezoelectric Actuator Using U-Shape PZT Strips and Lever Structure for Lateral Stroke Amplification (수평방향 변위증폭을 위해 U-형상의 PZT 스트립과 지렛대 구조를 이용한 압전구동형 액추에이터의 설계, 제작 및 실험)

  • 이준형;이택민;최두선;황경현;서영호
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.28 no.12
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    • pp.1937-1941
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    • 2004
  • We present lateral actuated piezoelectric actuator using U-shaped PZT strip and lever structure for the RF switch application. In the previous study of RF switch, they used horizontal contact switch fabricated by thin film metals. However, thin film metals could not generate large contact force due to low stiffness. In this work, we suggest lateral contact switch which makes large contact force by increasing stiffness. In addition, we use PZT actuator for the high force actuation. Generally actuator using thin film PZT moves to the vertical direction due to the neutral axis shift. Therefore we need lateral motion generation mechanism based on the thin film PZT actuator. In order to increase lateral motion of thin film PZT actuator, we use U-shaped PZT actuator using residual stress control. Also, thin film PZT actuator can generate very small lateral motion of 120${\times}$10$^{-6}$ ${\mu}{\textrm}{m}$/V for d$_{31}$ mode, thus we suggest lever structure to increase stroke amplification. From the experimental study, fabricated PZT actuator shows maximum lateral displacement of 1 ${\mu}{\textrm}{m}$, and break down voltage of the thin film PZT actuator is above 16V.

A Study on the Effect of Lateral Vibration of Sheet Pile on Vibratory Driving Force (널말뚝의 횡방향진동이 진동타입력에 미치는 영향에 대한 연구)

  • Lee, Seung-Hyun;Kim, Byoung-Il
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.8 no.4
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    • pp.848-852
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    • 2007
  • Many numerical analysis tools for predicting penetration speed of sheet pile are thought to be unreliable because they overestimate penetration speed for shallow depth of penetration. In order to overcome the defects of numerical analysis, lateral vibration model of sheet pile was suggested and energy consumption due to lateral vibration of sheet pile was estimated. Also, load reduction factor which explains reduction of vibratory driving force due to lateral vibration was introduced.

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A Study on the Vibration and Efficiency Characteristics of PMLSM According to Permanent Magnet Arrangement (영구자석 배열에 따른 PMLSM의 진동 및 효율 특성에 관한 연구)

  • Lee, Dong-Yeup;Lee, Seung-Hoon;Jang, Ki-Bong;Kim, Gyu-Tak
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.2
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    • pp.270-277
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    • 2009
  • This paper deals with a vibration and efficiency characteristics of Permanent Magnet Linear Synchronous Motor according to the PM arrangement. The generated force such as the thrust, detent force, normal force and lateral force are compared with analysis values and experimental ones. Furthermore characteristics of vibration and efficiency are estimated by experiments.

A morphologic evaluation of defects created by a piezoelectric ultrasonic scaler on casting gold alloy (압전방식초음파치석제거기의작업조건에따른치과주조용합금의삭제결손부 양상에 관한 고찰)

  • Kim, Young-Sung;Kim, Soo-Hwan;Kim, Won-Kyung;Lee, Young-Kyoo
    • Journal of Periodontal and Implant Science
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    • v.39 no.4
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    • pp.385-390
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    • 2009
  • Purpose: In this study we evaluated the morphologic aspects of defects created by a piezoelectric ultrasonic scaler with scaler tip on casting gold alloy using scanning electron microscope (SEM) images and defect surface profiles. Methods: 54 blocks of type III casting gold alloy (Firmilay, Jellenko Inc, CA, USA) were scaled by a piezoelectric ultrasonic scaler (P-MAX, Satelec, France) with scaler tip (No. 1 tip) on a sledge device. 2-dimensional profiles of defects on all samples were investigated by a surface profilometer (a-Step 500, KLA-Tencor, CA, USA). The selected working parameters were lateral force (0.5 N, 1.0 N, 2.0 N), mode (P mode, S mode), and power setting (2, 4, 8). SEM images were obtained. Defect surface profiles were made on Microsoft Excel program using data obtained by a surface profilometer. Results: Among P mode samples, there were similarities on defect surface profiles and SEM images regardless of lateral force. The defects created in P mode were narrow and shallow although the depth and the width increased as power setting changed low (2) to high (8). In P mode samples, the defect depth was the greatest when lateral force of 0.5 N was applied. However all the depths were smaller than 1 m. SEM images of Lateral force of 0.5 N, S mode, power setting 2 and 4 were similar to that of P mode, but the other SEM images of S mode showed discernible changes. Defect depth of S mode samples was the greatest when lateral force of 1.0 N was applied. Conclusions: Within the limitations of this study, it can be concoluded that removing capability of piezoelectric scaler with scaler tip becomes maximized as power level becomes higher but the capability is restricted when excessive lateral force is applied on scaler tip.

Characteristic of Additional Lateral Force Induced by Freight Car Loading CWR When Passing over Turnout and Curves (장대레일 화차의 분기부 및 곡선구간 통과시 추가횡압 발생에 관한 연구)

  • Kim, E.;Yang, S.C.;Lee, J.H.;Lee, J.D.
    • Proceedings of the KSR Conference
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    • 2002.05a
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    • pp.242-249
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    • 2002
  • This research suggests the assessment method of the additional lateral force caused bending moment of CWR when a freight car loading it is passing over turnout system or curves. The characteristics of lateral lone are analyzed by calculating the lateral pressure acting on the rails of conventional railway.

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Study on the Strength of Limit Axial Force and Accumulated Limit Axial Force of Concrete Filled Square Tube Columns (콘크리트 충전 각형강관 기둥부재의 한계축력 및 누적한계축력에 관한 연구)

  • Seo, Seong Yeon;Jung, Jin Ahn;Kim, Sung Yong
    • Journal of Korean Society of Steel Construction
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    • v.17 no.5 s.78
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    • pp.605-615
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    • 2005
  • Experimental and analytical work was conducted to investigate the relations of axial force and deformational capacity of concrete-filled square steel tube columns. The test series consisting of 36 columns were tested under the constant axial load and horizontal cyclic load. The axial force of the columns that resisted under the cyclic lateral load was defined as a certified strength of limit axial force. The analytical model was defined as a cantilever beam-column. The axial force of the beam-column that resisted under the cyclic lateral load was defined as an accumulated certified strength of limit axial force. The purpose of this study is to investigate the certified strength of limit axial force of concrete-filled steel tube beam-columns, which were subjected to both axial and lateral load condition corresponding to a given constant rotation angle. Another purpose of this study is to discuss the comparison of the certified strength of limit axial force of concrete and the accumulated certified strength of limit axial force of concrete-filled steel tube columns.

A Comparison of Friction Force Calibration in Lateral Force Microscope

  • Wang Yuli-Ang;Kim Hong-Joon;Kong Ho-Sung;Zhao Xu-Zheng;Yoon Eui-Sung
    • KSTLE International Journal
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    • v.7 no.1
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    • pp.5-9
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    • 2006
  • The main principle of two widely used methods which were proposed by Ruan and Bhushan, and by Ogletree and Carpick are introduced. Experiments were conducted using the two methods to measure friction force between AFM probe and silicon sample quantitatively. To characterize the frictional properties, the conversion factors of the two methods by which lateral electronic signal is converted into actual friction force were calculated. The experimental results show that that the conversion factors were extraordinarily different from each other. Further research should be done to identity the reasons for these differences.

EXPERIMENTAL STUDY ON THE RETENTION FORCE OF INLAY CAVITY (와동의 깊이 및 넓이의 변화가 Inlay 유지력에 미치는 영향에 관한 실험적 연구)

  • Hahn, Taik-Seon;Choi, Zai-Kyung
    • The Journal of the Korean dental association
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    • v.9 no.7
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    • pp.431-437
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    • 1971
  • The authors performed an experimental study on the retention force in cavities with various depth and width. We used the simple model cavities which were cylindrically formed to eliminate the unexpected influence during experiment, and obtained following results. 1. The retention force in the cavities with parallel wall was vigorous even in the small cavity and increased considerably followed by extending the cavity size. 2. The ratention force resulted more vigorously by that the depth became deeper than that the distance between the lateral walls became longer. 3. Compared with the retention force in the cavities which had the same frictional lateral surface, it was more vigorous in the deeper cavity than in the cavity which was longer distance between the lateral surfaces.

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A Study on the Modeling of Transitional Lateral Force Acting on the Berthing Ship by CFD

  • Kong, Gil-Young;Lee, Yun-Sok;Lee, Sang-Min
    • Journal of Mechanical Science and Technology
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    • v.18 no.7
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    • pp.1196-1202
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    • 2004
  • To evaluate the unsteady motion in laterally berthing maneuver, it is necessary to estimate clearly the magnitudes and properties of hydrodynamic forces acting on ship hull in shallow water. A numerical simulation has been performed to investigate quantitatively the hydrodynamic force according to water depth for Wigley model using the CFD (Computational Fluid Dynamics) technique. By comparing the computational results with the experimental ones, the validity of the CFD method was verified. The numerical solutions successfully captured some features of transient flow around the berthing ship. The transitional lateral force in a state ranging from the rest to the uniform motion is modeled by using the concept of circulation.