• Title/Summary/Keyword: Endplate

Search Result 85, Processing Time 0.023 seconds

Modelling of beam-to-column connections at elevated temperature using the component method

  • Sulong, N.H. Ramli;Elghazouli, A.Y.;Izzuddin, B.A.;Ajit, N.
    • Steel and Composite Structures
    • /
    • v.10 no.1
    • /
    • pp.23-43
    • /
    • 2010
  • In this paper, a nonlinear model is developed using the component method in order to represent the response of steel connections under various loading conditions and temperature variations. The model is capable of depicting the behaviour of a number of typical connection types including endplate forms (extended and flush) and angle configurations (double web, top and seat, and combined top-seat-web) in both steel and composite framed structures. The implementation is undertaken within the finite element program ADAPTIC, which accounts for material and geometric nonlinearities. Verification of the proposed connection model is carried out by comparing analytical simulations with available results of isolated joint tests for the ambient case, and isolated joint as well as sub-frame tests for elevated temperature conditions. The findings illustrate the reliability and efficiency of the proposed model in capturing the stiffness and strength properties of connections, hence highlighting the adequacy of the component approach in simulating the overall joint behaviour at elevated temperature.

PLL Control Method for Precise Speed Control of Slotless PM Brushless DC Motor Using 2 Hall-ICs (2 Hall-ICs를 이용한 Slotless PM Brushless DC Motor의 정밀속도제어를 위한 PLL 제어방식)

  • Woo M. S.;Yoon Y. H.;LEE T. W.;Won C. Y.;Choe Y. Y.
    • Proceedings of the KIPE Conference
    • /
    • 2004.07b
    • /
    • pp.665-669
    • /
    • 2004
  • Generally, Slotless PM BLDC drive system is necessary that the three Hall-ICs evenly be distributed around the stator circumference and encoder be installed in case of the 3 phase motor. So, the Hall-ICs are set up in this motor to detect the main flux from the rotor, and the output signal from Hall-ICs is used to drive a power transistor to control the winding current. However, instead of using three Hall-ICs and encoder, we used only two Hall-ICs for the permanent magnet rotor position and for the speed feedback signals, and also for a microcontroller of 16-bit type (80C196KC) with the 3 phase Slotless PM BLDC whose six stator and two rotor designed. Two Hall-IC Hc and $H_B$ are placed on the endplate at 120 degree intervals, and with these elements, we can estimate information of the others phase in sequence through a rotating rotor.

  • PDF

Numerical And Experimental Studies On Wing In Ground Effect

  • Suh, Sung-Bu;Jung, Kwang-Hyo;Chun, Ho-Hwan
    • International Journal of Ocean System Engineering
    • /
    • v.1 no.2
    • /
    • pp.110-119
    • /
    • 2011
  • Numerical and experimental studies were performed to investigate the aerodynamic performance of a thin wing in close vicinity to the ground. The vortex lattice method (VLM) was utilized to simulate the wing in ground (WIG) effect, which included freely deforming wake elements. The numerical results acquired through the VLM were compared to the experimental results. The experiment entailed varying the ground clearance using the DHMTU (Department of Hydromechanics of the Marine Technical University of Saint Petersburg) wing and the WIG craft model in the wind tunnel. The aero-dynamic influence of the design parameters, such as angles of attack, aspect ratios, taper ratios, and sweep angles were studied and compared between the numerical and experimental results associated with the WIG craft. Both numerical and experimental results suggested that the endplate augments the WIG effect for a small ground clearance. In addition, the vortex lattice method simulated the wake deformation following the wing in the influence of the ground effect.

Deformation Capacity of Endplate-type Beam-to-Column Connection with New Type Mechanical Fasteners (신형상 메카니컬패스너를 사용한 엔드플레이트 형식 보-기둥 접합부의 변형성능)

  • Lee, Seung-Jae
    • Journal of Korean Association for Spatial Structures
    • /
    • v.6 no.3 s.21
    • /
    • pp.123-130
    • /
    • 2006
  • This study propose cutting body portion-high strength mechanical fasteners to improve deformation capacity of High strength bolts, which are the mechanical fasteners used for End-plate connections. And, we report that loading test results of steel beam-to-column connection using high deformation capacity-high strength bolts in accordance with SAC2000 loading program. As a result, the initial stiffness and the maximum strength of the connection using high deformation capacity-high strength bolts, are approximately the same in comparison with those of the end-plate connection using the existing high strength bolts. But the deformation capacity of the connection is more than twice as much as those.

  • PDF

Effects of Spinal Stabilization Exercises on the Cross-sectional Areas of the Lumbar Multifidus and Psoas Major Muscles of Patients with Degenerative Disc Disease

  • Kim, Seong-Ho;Lee, Wan-Hee
    • The Journal of Korean Physical Therapy
    • /
    • v.22 no.3
    • /
    • pp.9-15
    • /
    • 2010
  • Purpose: To evaluate, in patients with degenerative disc disease (DDD), the efficacy of using spinal stabilizing exercises for the reversal? of atrophy of the multifidus and psoas major, reductions in pain and disability, and for increases in paraspinal muscle strength. Methods: Nineteen patients diagnosed with DDD participated for 10 weeks in a spinal stabilization exercise program. Pain and disability were measured before and after exercise using, respectively, a visual analogue scale (VAS) and the Oswestry Disability Index (ODI). Paraspinal muscular strength in four directions was evaluated using CENTAUR. Both before and after exercise we used computed tomography (CT) too measure cross-sectional areas (CSAs) of both the left and right multifidus and the psoas major at the upper & lower endplate of L4. Results: After 10 weeks of a spinal stabilization exercise program, pain was significantly decreased from $5.7{\pm}0.9$ to $2.5{\pm}0.9$ (p<0.01); the ODI score decreased from $16.7{\pm}4.9$ to $7.3{\pm}3.1$. Paraspinal muscle strength was significantly increased (p<0.01) and the CSAs of the left and right multifidus and psoas major muscles were significantly increased (p<0.01). Conclusion: Spinal stabilization exercise is effective in reversing atrophy in DDD patients, in reducing pain and disability, and in increasing paraspinal muscle strength. It is an effective treatment foro aiding rehabilitation in these cases.

An experimental study of connections between I-beams and concrete filled steel tubular columns

  • De Nardin, Silvana;El Debs, Ana Lucia H.C.
    • Steel and Composite Structures
    • /
    • v.4 no.4
    • /
    • pp.303-315
    • /
    • 2004
  • Frame composed of concrete-filled steel tubular columns and I-shaped steel beam has been researched in order to development reasonable connection details. The present paper describes the results of an experimental program in four different connection details. The connection details considered include through-bolt between I-shaped steel beams and concrete-filled steel tubular columns and two details of welded connections. One of the welded connection details is stiffened by angles welded in the interior of the profile wall at the beam flange level. The specimens were tested in a cruciform loading arrangement with variable monotonic loading on the beams and constant compressive load on the column. For through-bolt details, the contribution of friction and bearing were investigated by embedding some of the bolts in the concrete. The results of the tests show that through-bolt connection details are very ductility and the bearing is not important to the behavior of these moment connections. The angles welded in the interior of the profile wall increase the strength and stiffness of the welded connection detail. In addition, the behavior curves of these connections are compared and some interesting conclusions are drawn. The results are summarized for the strength and stiffness of each connection.

Three-Dimensional Flow Simulations around a Numerical Model of Wing-In-Ground(WIG) Effect Ship having the complex geometry (복잡한 해면효과익선 계산 모형 주위의 3차원 유동장의 수치계산)

  • PARK Jong-Chun;SHIN Myung-Soo
    • 한국전산유체공학회:학술대회논문집
    • /
    • 1996.05a
    • /
    • pp.85-92
    • /
    • 1996
  • Numerical simulations are made for the three-dimensional flow around a wing in ground effect craft haying the complex geometry. A numerical tool is developed for the primary design of hull and wing shape of practical Wing-In-Ground effect(WIG) stop. The finite-difference method is utilized to descretize the governing equations and pressure field is obtained by using Marker-And-Cell(MAC) method. The air and water flows are simultaneously simulated in the time-marching solution procedure for the Navier-Stokes equation. The porosity technique and the density function are devised for the implementation of the three-dimensional body-boundary and the free-surface conditions, respectively. In this paper, a craft is modeled simply by three blocks containing a wing mounted on a main body horizontally, with the endplate. The numerical calculations of a WIG advancing in a calm water are performed and the WIG-generated wave profiles are also obtained. In the final paper, details of the numerical methods employed for the present study and calculated results are discussed.

  • PDF

A Low Cost Speed Control System of PM Brushless DC Motor Using 2 Hall-ICs (2 Hall-ICs를 이용한 저가형 PM Brushless DC Motor속도 제어)

  • Kim D. K.;Yon Y. H.;Woo M. S.;Won C. Y.;Choe Y. Y.
    • Proceedings of the KIPE Conference
    • /
    • 2003.11a
    • /
    • pp.132-136
    • /
    • 2003
  • Generally, PM BLDC drive system is necessary that the three Hall-ICs evenly be distributed around the stator circumference and encoder be installed in case of the 3 phase motor. So, the Hall-ICs are set up in this motor to detect the main flux from the rotor, and the output signal from Hall-ICs is used to drive a power transistor to control the winding current. However, instead of using three Hall-ICs and encoder, we used only two Hall-ICs for the permanent magnet rotor position and for the speed feedback signals, and also for a micro controller of 16-bit type (80C196KC) with the 3 phase PM BLDC whose six stator and two rotor designed. Two Hall-IC Hc and $H_B$ are placed on the endplate at 120 degree intervals, and with these elements, we estimated information of the others phase in sequence through a rotating rotor.

  • PDF

Initial stiffness and moment capacity assessment of stainless steel composite bolted joints with concrete-filled circular tubular columns

  • Wang, Jia;Uy, Brian;Li, Dongxu
    • Steel and Composite Structures
    • /
    • v.33 no.5
    • /
    • pp.681-697
    • /
    • 2019
  • This paper numerically assesses the initial stiffness and moment capacity of stainless steel composite bolted joints with concrete-filled circular tubular (CFCT) columns. By comparing with existing design codes including EN 1993-1-8 and AS/NZS 2327, a modified component method was proposed to better predict the flexural performance of joints involving circular columns and curved endplates. The modification was verified with independent experimental results. A wide range of finite element models were then developed to investigate the elastic deformations of column face in bending which contribute to the corresponding stiffness coefficient. A new design formula defining the stiffness coefficient of circular column face in bending was proposed through regression analysis. Results suggest that a factor for the stiffness coefficient of endplate in bending should be reduced to 0.68, and more contribution of prying forces needs to be considered. The modified component method and proposed formula are able to estimate the structural behaviour with reasonable accuracy. They are expected to be incorporated into the current design provisions as supplementary for beam-to-CFCT column joints.

Meridian Sinews and Sagittal Spinal Balance (경근(經筋)과 인체 시상균형에 관한 소고(小考))

  • Nam, Tong-Hyun;Shin, Sang-Hun
    • The Journal of the Society of Korean Medicine Diagnostics
    • /
    • v.13 no.2
    • /
    • pp.129-139
    • /
    • 2009
  • Sagittal spinal balance means standing postural balance at sagittal plane. Postural imbalance with displacement of the patient's center of gravity can cause chronic back pain and ambulatory difficulty. The sagittal spinal balance is determined based on the deviation of the C7 plumb line, originating at the middle of the C7 vertebral body, from the posterior superior endplate of S1. The line is called as sagittal vertical axis (SVA). In the traditional Korean medicine, the meridian sinews, which are the most superficial pathways of the meridian system, associated with movement, muscle balance and defense. They too are separate from the main meridians, though they intersect the main meridians. Some creative and pioneer researchers in Korea thought that the anatomy trains, which suggested by Myers is a concept familiar to the meridian sinews. A reciprocal relationship between the superficial back line and the superficial front line used to be compared to the rigging of a sailboat. Therefore, We suggest that spine may be compared to a mast of the sailboat and that the sagittal spinal balance can be maintained with systemic reciprocal interacts between the front line muscles and the back.

  • PDF