• Title/Summary/Keyword: vertical lift

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Rotordynamic Transient Analysis of Vertical Sea Water Lift Pump for FPSO Deep Well (FPSO 심정용 수직 해수펌프의 로터다이나믹 과도해석)

  • Kim, Byung-Ok;Yang, Sung-Jin;Lee, Myung-Ho
    • The KSFM Journal of Fluid Machinery
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    • v.14 no.5
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    • pp.69-74
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    • 2011
  • This paper deals with the detail rotordynamic analysis for the vertical rotor system as development of vertical sea water lift pump for FPSO deep well. In a vertical rotor system, since linearized stiffness and damping coefficients of fluid film bearing are no longer be valid, hence the transient response analysis considering a fluid film force for every journal position in the bearing needs to be required. In this study, the transient response analysis of the proposed vertical pump rotor system was carried out in dry-run and wet-run conditions, respectively. The results show that orbital vibration responses of the rotor system remain stable at rated speed and thereby operating reliability of the vertical rotor system is confirmed. To overcome complexity of calculation pr ocedure and time consuming calculation of transient analysis, the calculating technique of steady-state response analysis is also proposed. The results of steady-state response obtained by applying the proposed technique to the rotor system are good agreement with the reference results, that is, transient responses.

A Decision-Making Model of Integrated Vertical and Horizontal Move Plan for Finishing Material in Righ-Rise Building Construction (고층건물공사 마감자재의 수직$\cdot$수평이동계획이 통합된 의사결정모델)

  • Ahn Byung-Ju;Kim Jae-Jun
    • Korean Journal of Construction Engineering and Management
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    • v.2 no.2 s.6
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    • pp.47-58
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    • 2001
  • Of all the site logistics technologies in high-rise building construction, both vertical and horizontal move plan, are the most imperative factors. And the horizontal plan follows lift-up plan as of the vertical plan. However though it may be, temporary lifts on site are numbered by heuristic formulas. The quantity of finishing material cannot be converted into lift-up load per finishing material. The lift-up plan cannot be evaluated the feasibility for finishing material move plan by a reasonable evaluation methodology. The horizontal plan is far from the vertical one. And the information as an input data for the horizontal plan is devoid of package unit size, length, and volume per finishing material. These can hardly result in reasonable and detail decision on how much to use temporary lifts, how long to use these, and where to deposit each finishing material. Therefore, this study is to suggest a decision-making model that can integrate vertical and horizontal material move plan in high-rise building construction and make a decision the plans systematically. And the study is to explain the concept, methodology, and contents of the model applied to a virtual project, named as MT 130 (Millennium Tower 130). By the model, the planner can shift his/her thinking framework on site logistics management products-oriented Into process-oriented. He/she can manage a project by the framework as system thinking, evaluate the feasibility of a lift-up plan, and decide the horizontal plan integrated with the lift-up.

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Response of a finite beam on a tensionless Pasternak foundation under symmetric and asymmetric loading

  • Coskun, Irfan;Engin, Hasan;Ozmutlu, Aydin
    • Structural Engineering and Mechanics
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    • v.30 no.1
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    • pp.21-36
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    • 2008
  • The static response of a finite beam resting on a tensionless Pasternak foundation and subjected to a concentrated vertical load is assessed in this study. The concentrated vertical load may be applied at the center of the beam, or it may be offset from the center. The tensionless character of the foundation results in the creation of lift-off regions between the beam and the foundation. An analytical/ numerical solution is obtained from the governing equations of the contact and lift-off regions to determine the extent of the contact region. Although there is no nonlinear term in the equations, the problem shows a nonlinear character since the contact region is not known in advance. Due to that nonlinearity, the essentials of the problem (the coordinates of the lift-off points) are calculated numerically using the Newton-Raphson technique. The numerical results are presented in figures to illustrate the behaviours of the free-free and pinned-pinned beams under symmetric or asymmetric loading. The figures illustrate the effects of the shear foundation parameter and the symmetric and asymmetric loading options on the variation of the contact lengths and the displacement of the beam.

An Estimating Mehod of the Angle of Attack of a Vertical V-type Otter Board (종만곡 V형 전개판의 영각 추정법)

  • Park, Hae-Hoon
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.41 no.2
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    • pp.113-121
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    • 2005
  • How to extimate the angle of attack of a vertical V-type cambered otter board was described. A three-dimensional semi-analytic treatment of a towing cable system was applied to the field experiments of a midwater trawl obtained by the Scanmar system. Also the equilibrium condition of the horizontal component and vertical component of forces and moment around the otter board was used. When the warp length was 300m long and the towing speed was between 2.61 and 3.86 knots, the estimated angle of attack of the otter board was ranged between $24.7^{\circ}$ and $26.2^{\circ}$, though the maximum lift force was at the angle of attack $22^{\circ}$.

Structural Analysis of Lift-Fan Rotor for Jet-VTOL Aircraft

  • Hojo, Masahiro;Ogawa, Akinori;Saito, Yoshio;Hashimoto, Ryosaku
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2004.03a
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    • pp.521-523
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    • 2004
  • The Japan Aerospace Exploration Agency (JAXA) has proposed new vertical take-off and landing (VTOL) aircraft known as the Jet-VTOL aircraft shown in Fig.1. The Jet-VTOL aircraft is based on a canard wing configuration. The aircraft has the clustered lift-fans mounted near the center of gravity for vertical flight, and has the clustered fans mounted beside the vertical tail for cruise flight. Both fans are driven by the core engine mounted inside the aft end of fuselage. The propulsion system is innovative and attractive not to be seen even in the world.

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Two Cases of Lower Body Contouring with a Spiral and Vertical Medial Thigh Lift

  • Kim, Sang-Wha;Han, Hyun-Ho;Seo, Je-Won;Lee, Jung-Ho;Oh, Deuk-Young;Ahn, Sang-Tae;Rhie, Jong-Won
    • Archives of Plastic Surgery
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    • v.39 no.1
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    • pp.67-70
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    • 2012
  • Massive weight loss results in skin excess, leading to an unsatisfying body contour. Various thigh lift procedures can correct flabby skin in the lower leg. We present a lower body contouring technique with a report on two patients. The procedure is determined by the body contour of the patient. As the skin excess in the thigh area tended to appear mostly on the medial side, a vertical medial thigh lift was considered. Moreover, for patients with a pear/guitar-shaped body contour, we added the spiral thigh lift for skin excess in the buttocks and the lateral thigh area. The extent of tissue to excise was determined by pinching the patient in a standing position. The inferior skin flap was fixed to non-movable tissue, which was helpful for lifting the tissue and preventing the widening of the scar. After the operation, a drain was kept for 3 to 4 days. A compressive garment was used after removing the drain. There were no complications. The patients were discharged 6 to 8 days after the operation. In conclusion, skin excess, especially in the lower body, can be corrected by a thigh lift combining several procedures, varying from person to person.

Motion Characteristics of Particle in Model GIS (모의 GIS내 금속이물의 거동특성)

  • 김경화;이재걸;곽희로
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.13 no.4
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    • pp.152-159
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    • 1999
  • This paper describes the rmtion characteristics of a particle in GIS under AC voltage. To measure the motion characteristics of the particle, a model gas chamber and parallel plain electrodes were designed and manufactured lift-off voltages of wire and spherical particles on the electrode were calculated and rreasured, and electric charge was calculated. By using a high speed carrera, the rmtion characteristics of various particles with aw}ied voltages, such as motion pattern, lift-off time, lift-off height, were analyzed 1be lift-off voltages were greatly affected by diarreters of wire and spherical particles. At voltage around lift-off voltage, the stand-up particle in vertical state rmved up and down between electrodes and the height of the lift-off particle was low. At voltage around breakdown voltage, the particle repeated vertical rotation a few times while they were being lifted off, and then, they were floating between the electrodes.trodes.

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Fracture Analysis of a Spindle in the X-Lift (X 리프트 스핀들의 파괴해석)

  • Chu, Seok-Jae
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.32 no.1
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    • pp.91-98
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    • 2008
  • One of the two spindles in the X-lift fractured suddenly during normal operation. The fracture occurred at the notch where the bending moment might be the maximum. Macrofractographic features associated with rotating-bending fatigue are evident on the fracture surface. The 3-D finite element analysis of the X-lift reveals that the spindle rotated under bending. The measured surface strain of the spindle varies cyclically as the spindle rotates. It supports that the spindle rotated under bending. The X-lift is not perfectly symmetrical with respect to both the horizontal and the vertical plane. The slightly unsymmetrical deformation can cause the bending of the spindle.

Vertical Lift of Vector Fields to the Frame Bundle

  • Mishra, A.K.;Singh, R.N.
    • The Mathematical Education
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    • v.29 no.1
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    • pp.63-68
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    • 1990
  • Let M be a differentiable manifold, TM its tangent bundle and FM its frame bundle. The theory of complete lifts and Horizontal lifts to FM of vector fields on M ahs been studied by many authors. Tn this paper, vertical lifts of functions vector fields md 1-forms on M to FM are studied.

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