• 제목/요약/키워드: Center Force

검색결과 2,558건 처리시간 0.034초

로드셀을 사용한 2 차원 반력측정반 (Development of a Prototype Force Plate Employing Load Cells)

  • 박지희;강곤
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1994년도 추계학술대회
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    • pp.178-180
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    • 1994
  • We developed a prototype force plate equipped with five load cells, a 12-bit analog-to-digital converter and three integrated circuits. The force plate displays the center of foot pressure, the magnitude and two (vertical and anterior-posterior) directions of the ground reaction force on a personal computer monitor. Although the force plate data are valid only for two directions, it can be a preliminary version of a more versatile 3 dimensional force plate in terms of the resolution and reliability.

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Frequency domain analysis of Froude-Krylov and diffraction forces on TLP

  • Malayjerdi, Ebrahim;Tabeshpour, Mohammad Reza
    • Ocean Systems Engineering
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    • 제6권3호
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    • pp.233-244
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    • 2016
  • Tension Leg Platform (TLP) is a floating structure that consists of four columns with large diameter. The diffraction theory is used to calculate the wave force of floating structures with large dimensions (TLP). In this study, the diffraction and Froude-Krylov wave forces of TLP for surge, sway and heave motions and wave force moment for roll, pitch degrees of freedom in different wave periods and three wave approach angles have been investigated. From the numerical results, it can be concluded that the wave force for different wave approach angle is different. There are some humps and hollows in the curve of wave forces and moment in different wave periods (different wavelengths). When wave incidents with angle 0 degree, the moment of diffraction force for pitch in high wave periods (low frequencies) is dominant. The diffraction force for heave in low wave periods (high wave frequencies) is dominant. The phase difference between Froude-Krylov and diffraction forces is important to obtain total wave force.

계단형상 체적의 엔드밀 가공시 절삭력 변화 특성에 관한 연구 (Cutting Force Variation Characteristics in End Milling of Terrace Volume)

  • 맹희영
    • 한국생산제조학회지
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    • 제22권3_1spc호
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    • pp.489-495
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    • 2013
  • This study analyzed thevariation in the cutting force when the cutting area of a terrace volume is machined, which is generally left after the rough cutting of a sculptured surface. The numerically simulated results for the cutting forces are compared with cutting force measurements by considering the theoretical prediction of the cutting area formation and specific cutting volume. The variation in the cutting force is measured using a dynamometer installed on a machining center for 19 different kinds of test pieces, which are selected according to the variation in the terrace volume factor, tool diameter factor, and cutting depth factor. As a result, it is verified that the cutting forces evaluated by the numerical analysis coincide with the measured cutting forces, and it is proposed as a practical cutting force prediction model.

타이어의 최적 노면 마찰력을 고려한 ABS 슬라이딩 모드 제어 (ABS Sliding Mode Control considering Optimum Road Friction Force of Tyre)

  • 김정식
    • 한국자동차공학회논문집
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    • 제21권1호
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    • pp.78-85
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    • 2013
  • This paper presents the sliding mode control methods for anti-lock brake system (ABS) with the friction force observer. Using a simplified quarter car model, the sliding mode controller for ABS is designed to track the desired wheel slip ratio. Here, new method to find the desired wheel slip ratio which produces the maximum friction force between road and tire is suggested. The desired wheel slip ratio is varying according road and tire conditions to produce maximum friction force. In order to find optimum desired wheel slip ratio, the sliding mode observer for friction force is used. The proposed sliding mode controller with observer is evaluated in simulation, and the control design is shown to have high performance on roads with constant and varying adhesion coefficients.

3D FEM해석을 통한 배선용 차단기의 가동자 거동해석 (Dynamic Motion Analysis of a Moving Contact by Electromagnetic Repulsion Force in MCCB)

  • 송중천;김용기;유만종;서정민
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 하계학술대회 논문집 B
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    • pp.786-789
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    • 2002
  • The behaviour of contactors protected by arcs under short-circuit currents is analysed using a simple model to represent the electric circuit and the contactor. In most cases, the protection of contactors against short-circuit currents is entrusted to fuses. Fuses are suitable for preventing excessive damage to the contactor, or parts of the contactor, under short-circuit conditions. In particular, they are capable of limiting the thermal and electrodynamic stresses which can lead to arcing or welding together of the contacts of a contactor. This paper is the Dynamic Motion Analysis of a Moving Contact by Electromagnetic Repulsion Force in Molded Case Circuit Breaker(MCCB)

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가수분해된 인삼사포닌 4급 암모늄엽과 화장품으로의 응용에 관한 연구 (A Study on the Hydrolyzed Ginseng Saponin-Quaternary and its Application in Cosmetics)

  • 김영대;김창규;이정남;하병조
    • Journal of Ginseng Research
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    • 제13권2호
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    • pp.189-197
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    • 1989
  • A new quaternary ammonium compound, hydrolyzed ginseng-saponin quaternary (HGSQ), from Korean ginseng saponin and 2,3-epoxypropyltrimethylammonium chloride has been developed as a conditioning agent in cosmetics. This structure has a hydrophobic group from the aglycone of ginseng saponin which is biologically active and considered to be the most important component of the Korean ginseng. Its properties : surface tension, critical micelle concentration (CMC), eye irritation, sorption onto hair, force reduction(%) and moisture retention effect were studied. Its cationic character allows the molecule to be more substantive than ginseng saponin. HGSQ had good physical properties and was safe. enough as a cosmetic raw material. Also half-head tests of HGSQ-containing shampoo were carried out to compare the conditioning effects in shampoos. HGSQ was an excellent conditioning agent in shampoo..

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가터스프링에 의한 튤립접촉자의 설계 고찰 (Design Review of Tulip Contactor by Garter Spring)

  • 조상순;박우진;안길영;오일성
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 추계학술대회 논문집 전기물성,응용부문
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    • pp.242-245
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    • 2003
  • A garter spring, which is a long, special, close-coiled extension spring with its ends joined to form a ring, is used in tulip contactor between vacuum circuit breaker and bus bar in switchgear. To carry short-time current and resist welding at the contact surface in the tulip contactor, the garter spring must transmits an uniform contact force to the contact surface through the contact chips arranged in the circumference of bus bar. In this paper, the system for measurement of the contact force by the garter spring is developed. Using the developed measurement system, the design of the connection structure including the garter spring is reviewed to obtain the uniform contact forces in all of contact chips.

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Comparative Study of Stator Core Composition in Transverse Flux Rotary Machine

  • Lee, Ji-Young;Moon, Seung-Ryul;Koo, Dae-Hyun;Kang, Do-Hyun;Lee, Geun-Ho;Hong, Jung-Pyo
    • Journal of Electrical Engineering and Technology
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    • 제6권3호
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    • pp.350-355
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    • 2011
  • This paper deals with the comparison of magnetic characteristics in transverse flux rotary machine according to different stator core composition with the same rotor. Three different stator designs are considered in the analysis according to the material composition of inner and outer stator cores. Electromotive force (EMF), inductance, torque, and core losses are calculated by threedimensional finite element analysis. Calculated and measured results of back-EMF according to the analysis models in dependency on speed are presented.

Magnetization Behavior of Co Nanodot Array

  • Chang, Joon-Yeon;Gribkov, B.A.;Kim, Hyung-Jun;Koo, Hyun-Cheol;Han, Suk-Hee;Mironov, V.L.;Fraerman, A.A.
    • Journal of Magnetics
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    • 제12권1호
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    • pp.17-20
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    • 2007
  • We performed magnetic force microscopy (MFM) observation on array of Co dots in order to understand magnetic state and magnetization behavior of submicron sized Co dots patterned on GaMnAs bridge. MFM observations showed the magnetization reversal and processes of local magnetization of individual ferromagnetic Co nanodots. Magnetic state of Co dots either single domain or vortex is dependent on geometrical size and thickness. Transition from single domain to vortex state can be realized with MFM tip assisted local field. Magnetization reversal process takes place through sequential reversal of individual dots. Localized inhomogeneous magnetic field can be manipulated by controlling magnetic state of individual Co dot in the array structure.

네스핏 트레킹화와 평면 인솔 트레킹화의 족저압력 분석 (Analysis of Plantar Pressure Differences between Flat Insole Trekking Shoes and Nestfit Trekking Shoes)

  • 최재원;이중숙
    • 한국운동역학회지
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    • 제25권4호
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    • pp.475-482
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    • 2015
  • Objective : The purpose of this study was to investigate mean plantar foot pressure, maximum plantar pressure and ground reaction force, and center migration path of pressure according to the type of trekking shoes for the development of shoes. Method : Subjects of the study averaged $22.10{\pm}2.05years$ of age. Their average height was $169.27{\pm}7.62cm$ and their average weight was $64.34{\pm}10.22kg$. The method of this study was administered measuring 50 steps, at once, 3 times at a speed of 4 km/h and using the data of 30 steps. Pedar-X system measured the mean foot pressure, maximum foot pressure, mean maximum force, and center migration path of pressure by subjects' position while walking. Statistical analysis was performed by SPSS 23.0 using a paired t-test. Results : Results of the study showed Nestfit trekking shoes lower foot pressure of both feet in mean foot pressure and maximum foot pressure. Nestfit trekking shoes showed high ground reaction force (p<.001) in the midfoot, and low mean ground reaction force in the rearfoot. The center migration path of pressure showed the Nestfit trekking shoes were more stable than flat insole trekking shoes. Conclusion : It can be concluded that wearing Nestfit trekking shoes spreads pressure efficiently and induces walking stability because Nestfit trekking shoes spread the pressure of the forefoot and rearfoot to the midfoot and the center migration path of pressure shows regularly.