• 제목/요약/키워드: fixed plate

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Elastic Buckling Characteristics of Plate Girder Web Panel (경량전철 2주형 판형교 복부판의 탄성좌굴 특성)

  • 황민오;성택룡;윤태양;이안호
    • Proceedings of the KSR Conference
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    • 2000.11a
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    • pp.344-351
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    • 2000
  • In the design of plate girder web panels, it is required to evaluate accurately the elastic buckling strength under pure shear, pure bending and combined bending and shear. Currently, elastic buckling coefficients of web panels stiffened by transverse intermediate stiffeners are determined by assuming conservatively that web panels are simply supported at the juncture between the flange and web. However, depending upon the geometry and the properties of the plate girder bridge, upper juncture between the flange and web can be assumed as fixed because concrete deck prevents the rotational displacement of upper flange. In the present study, a series of numerical analyses based on finite element modeling is carried out to investigate the effects of the concrete deck, and the resulting data are quantified in simple equations.

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A comparison study for the track maintenance system for the non-ballast steel plate bridge (무도상 판형교 레일 장대화에 따른 궤도 유지관리 비교연구)

  • Nam, Bo-Hyun;Jang, Tae-Cheol;Woo, Yong-Keun;Min, Kyung-Ju
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.401-410
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    • 2007
  • Form the application of long rail system the non-ballast steel plate bridges, fatigue strength increase and rail noise reduction can be expected. This is mainly form the reduction of the rail impact at the rail joint locations which already made to behave together from welds. In the high speed rail, application of long rail system is essential because without long rail system, the required serviceability level can not be achieved. But even with this long rail systems, the thermal expansion from the girder can not be absorbed in the normal bearing systems, and these expansion cause between girder and rail. Also unexpected rail buckling and fracture through rail thermal tension may happen. It was found through numerical analysis and field measurement that these problems can be avoided by semi-fixed bearing system. In this study, the benefits of non-ballast plate bridge through long rail system, especially at the point of girder stability, girder stiffness increase and bearing maintenance will be reviewed.

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On the Uncertain Behavior of Mindlin Plates (Mindlin 평판의 불확실거동에 대하여)

  • Noh, Hyuk-Chun;Kim, In-Ho
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2007.04a
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    • pp.465-470
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    • 2007
  • In order to investigate the stochastic behavior of Mindlin plate under imperfection in the material and geometrical parameters, a stochastic finite element formulation is proposed. The effects of inter-correlations between random parameters on the response variability are also observed. The contribution from the random Poisson ratio is taken into account adopting a stochastic decomposition scheme. which expands the constitutive matrix into an infinite series of sub-matrices. In order to demonstrate the adequacy of the proposed scheme, a square plate with simple and fixed support is taken as an example, and the results are compared with those given in previous research in the literature as well as with the results of Monte Carlo analysis.

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Shape Optimization of a Thomson Coil Actuator for Fast Response Using Topology Modification

  • Li, Wei;Koh, Chang-Seop
    • Journal of Electrical Engineering and Technology
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    • v.7 no.3
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    • pp.330-335
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    • 2012
  • The shape optimization of a Thomson coil actuator used in an arc eliminator is done for fast response by adopting topology modification method. The displacement of the plate in a fixed calculation time is taken as the objective function. The objective function and contribution factor are calculated by using an adaptive equivalent circuit method which has been proved accurate and efficient. Both shape optimization and performance analysis are accomplished based on the segmentation of plate. Through the refinement of the sensitive segments a precise optimal plate shape can be obtained. The effectiveness of the proposed method is proved by the comparison of results before and after the shape optimization.

Shape Optimization of a Thomson Coil Actuator for Fast Response Using Topology Modification

  • Li, Wei;Koh, Chang-Seop
    • Journal of Electrical Engineering and Technology
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    • v.7 no.1
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    • pp.58-63
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    • 2012
  • The shape optimization of a Thomson coil actuator used in an arc eliminator is done for fast response by adopting topology modification method. The displacement of the plate in a fixed calculation time is taken as the objective function. The objective function and contribution factor are calculated by using an adaptive equivalent circuit method which has been proved accurate and efficient. Both shape optimization and performance analysis are accomplished based on the segmentation of plate. Through the refinement of the sensitive segments a precise optimal plate shape can be obtained. The effectiveness of the proposed method is proved by the comparison of results before and after the shape optimization.

An Experimental Study on the Warpage of a Film Insert Molded Plate (필름 인서트 사출성형 평판의 휨 변형에 관한 실험적 연구)

  • Yoo, Y.G.;Lee, H.S.
    • Transactions of Materials Processing
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    • v.21 no.1
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    • pp.30-35
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    • 2012
  • FIM(Film Insert Molding) is an innovative method of producing decorated parts for a wide range of products. Because it requires fewer steps when compared to conventional production methods, the time and cost of manufacturing high quality components can be reduced considerably. In this paper, the effects of processing conditions on the warpage of film-insert molded plate were investigated by using a design of experiments. The dominant factors affecting warpage were mold temperature and holding pressure. Warpage increased with the temperature difference between stationary mold and fixed one. Even when the mold temperature difference was zero, the plate with a film was bent after ejection such that the film side protruded. As holding pressure increased, warpage decreased significantly. In addition warpage increased with time increment for the film-insert molded plates.

Early wound healing of the hard-palate mucosal harvest site using artificial dermis fixation by a transparent plate

  • Suzuki, Yushi;Tanaka, Ichiro;Sakai, Shigeki;Yamauchi, Tomohiro
    • Archives of Plastic Surgery
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    • v.48 no.2
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    • pp.208-212
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    • 2021
  • Background There are currently no guidelines for the postoperative wound management of the hard-palate donor site in cases involving mucosal harvesting. This study describes our experiences with the use of an artificial dermis for early epithelialization and transparent plate fixation in cases involving hard-palate mucosal harvesting. Methods A transparent palatal plate was custom-fabricated using a thermoplastic resin board. After mucosal harvesting, an alginic acid-containing wound dressing (Sorbsan) was applied to the donor site, which was then covered with the plate. After confirming hemostasis, the dressing was changed to artificial dermis a few days later, and the plate was fixed to the artificial dermis. The size of the mucosal defect ranged from 8×25 to 20×40 mm. Results Plate fixation was adequate, with no postoperative slippage or infection of the artificial dermis. There was no pain at the harvest site, but a slight sense of incongruity during eating was reported. Although the fabrication and application of the palatal plate required extra steps before and after harvesting, the combination of the artificial dermis and palatal plate was found to be very useful for protecting the mucosal harvest site, and resulted in decreased pain and earlier epithelialization. Conclusions The combination of artificial dermis and a transparent palatal plate for wound management at the hard-palate mucosal donor site resolved some of the limitations of conventional methods.

Effect of trace amount of ferrous and ferric ions on the dissolution of iron plate in magnetically treated 3% sodium chloride solution

  • Chiba, Atsushi;Ohki, Tomohiro;Wu, Wen-Chang
    • Corrosion Science and Technology
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    • v.4 no.2
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    • pp.45-50
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    • 2005
  • A 3% NaCl solution of 1 $dm^3$ circulated with 1.5 $dm^3/min$ by a pump for 24 h in the presence of magnetic field. An iron plate immersed in a $100cm^3$ of test solution for 24 h. The rest potential and pH on surface fixed after 3 h. Containing 0~120 ppm of Fe(II) ion, the dissolution in the magnetically treated solution rose comparing with that in the non-magnetically treated solution. The dissolution amount reached to maximum at 50 ppm, then fixed in the non-magnetically treated solution. When Fe(II) ion existed in the magnetically treated solution, dissolution accelerated a little. In the non-magnetic treated solution containing 10~125 ppm of Fe(III) ion existed, the dissolution accelerated. The dissolution amounts reached to maximum at 50 ppm, then decreased from maximum value. In the magnetically treated solution, the dissolution amounts reached to minimum until 50 ppm, then increased from minimum value. The dissolution amounts affected larger with increasing of magnetic flux density. Fe(II), Fe(III) ions and magnetic treatment affected to formation of $Fe(OH)_2$ and/or $Fe_3O_4$ films. The magnetically treated effects memorized about one month.

Condyle dislocation following mandibular reconstruction using a fibula free flap: complication cases

  • Kang, Sang-Hoon;Lee, Sanghoon;Nam, Woong
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.41
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    • pp.14.1-14.10
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    • 2019
  • Background: Condylar dislocation can arise as a complication in patients who required mandibular and/or condylar reconstruction and were operated on with fibula free flap (FFF) using surgical guides designed using simulation surgery. Surgeons should be aware of the complications in these present cases when planning and performing reconstructions as well as predicting prognoses. Cases presentation: Two cases showed condylar dislocation in mandibular reconstruction using a FFF fixed with a reconstruction plate. Three cases showed condylar dislocation in mandibular reconstruction using a fibula free flap fixed with a mini-plate. Conclusion: Despite the lack of clinical symptoms in these cases following mandibular reconstruction using an FFF, the mandibular condyle was severely displaced away from the glenoid fossa. A surgeon must have sufficient time to consider the use of a long flap with thickness similar to that of the mandible, ways to minimize span and bending, and methods of fixation. The patient, moreover, should be educated on condylar dislocation. Customized CAD/CAM-prototyped temporomandibular condyle-connected plates may be a good alternative even if virtual simulation surgery is to be performed before surgery. These considerations may help reduce the incidence of complications after mandibular reconstruction.

Plate Type New Distributor Development for Hydraulic Motors and Pumps (유압모터 및 펌프용 판 형태의 새로운 분배기 개발)

  • Jin, Seong-Mu;Kim, Hyeong-Ui
    • 한국기계연구소 소보
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    • s.18
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    • pp.75-85
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    • 1988
  • The distributor for hydraulic pumps or motors, particularly radial piston motors, include rotary member which has equally both surface shape for dynamic balance and two fixed members, located in both side of rotary member, which have equal surface shape for dynamic balance and circular ring which use to retain predetermined clearance between two fixed members. Rotary member must have valve part for flow-distribution and can have hydrostatic bearing for excellently dynamic balance. At least two annular steps located on said pressure plate which use in compensation of bolt expansion.

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