• 제목/요약/키워드: Re-tension

검색결과 79건 처리시간 0.029초

견의 정련 방법에 관한 연구(1) - 패키지 정련 - (A Study on the Silk Degumming(1) - Degumming of Silk on Package -)

  • 김문식;김용학
    • 한국염색가공학회지
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    • 제18권3호
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    • pp.16-22
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    • 2006
  • Process contract has received considerable attention in silk degumming processes because of its critical role in quality assurance. In degumming, process exhibits shrinkage of high twisted yarn and lot-varying behavior, thus increasing the difficulties of reduction by conventional means. This necessitates the application of a package that adapts to changing degumming process, and a new approach involving package degumming is proposed. The gains of this process are prevent of shrinkage by package winding, which is simplified by reduced soft-winding or re-twisting process. The approach is expected to achieve high quality results in conventional process due to its feature of demage by tension and rubbing. Therefore package degumming has many merits such as reduce of pilling and shrinkage, production expenses saving by process contract are expected of the simplified degumming process.

Mixed mode I/II fracture criterion to anticipate behavior of the orthotropic materials

  • Farid, Hannaneh Manafi;Fakoor, Mahdi
    • Steel and Composite Structures
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    • 제34권5호
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    • pp.671-679
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    • 2020
  • The new energy-based criterion, named Reinforcement Strain Energy Density (ReiSED), is proposed to investigate the fracture behavior of the cracked orthotropic materials in which the crack is embedded in the matrix along the fibers. ReiSED is an extension of the well-known minimum strain energy density criterion. The concept of the reinforced isotropic solid as an advantageous model is the basis of the proposed mixed-mode I/II criterion. This model introduces fibers as reinforcements of the isotropic matrix in orthotropic materials. The effects of fibers are qualified by defining reinforcement coefficients at tension and shear modes. These coefficients, called Reduced Stress (ReSt), provide the possibility of encompassing the fiber fraction in a fracture criterion for the first time. Comparing ReiSED fracture limit curve with experimental data proves the high efficiency of this criterion to predict the fracture behavior of orthotropic materials.

Reconstruction of partial maxillectomy defect with a buccal fat pad flap and application of 4-hexylresorcinol: a case report

  • Seok, Hyun;Kim, Min-Keun;Kim, Seong-Gon
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제42권6호
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    • pp.370-374
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    • 2016
  • Mucoepidermoid carcinoma (MEC) is the most common type of malignant neoplasm in the minor salivary gland. The hard palate is a frequently involved site of MEC. The treatment of low-grade MEC on the hard palate is wide local resection with a tumor-free margin. In the present case, the maxillary defect was reconstructed using a buccal fat pad (BFP) flap, followed by application of 4-hexylresorcinol (4HR) ointment for 2 weeks. The grafted BFP successfully covered the tumor resection defect without tension and demonstrated complete re-epithelialization without any complications.

포스트텐션 조립식 교각의 유효프리스트레스 크기 결정 (Determination of Effective Prestress of Post-tensioned Precast Bridge Piers)

  • 심창수;코엠찬다라
    • 한국지진공학회논문집
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    • 제20권3호
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    • pp.135-143
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    • 2016
  • In this paper, a design concept of post-tensioned precast bridge piers was proposed to improve seismic behavior of the bridge pier. Mild reinforcing bars are placed continuously along the height of the column. Prestressing tendons are also provided to obtain re-centering capability for seismic events. Arrangement of the axial steels to prevent buckling of rebars at plastic hinge region was suggested and enhanced seismic performance was verified by experiments. Moment-curvature analyses were performed to evaluate the effect of effective prestress on seismic behavior after verifying the calculation method by cyclic tests of the precast columns. A real bridge pier was designed to investigate the seismic performance according to different level of effective prestress. Level of effective prestress showed obvious effect on crushing displacement but negligible effect on lateral displacement at fracture of tendons and reinforcements.

Dynamic Free-surface Deformations in Axisymmetric Liquid Bridges

  • Sim B.-C.;Kim W.-S.;Zebib A.
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2003년도 The Fifth Asian Computational Fluid Dynamics Conference
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    • pp.160-161
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    • 2003
  • Thermocapillary convection is a surface tension driven flow due to a temperature gradient along an interface. It occurs during a crystal-growth process and therefore understanding the convection is important to material processing in microgravity. Although modelling of the float-zone crystal-growth process has been of interest for a few decades, most studies of liquid bridges assumed non-deformable flat surfaces. In reality, the surface profile, g(t,z), is unknown and should be obtained as a solution to the coupled transport equations along with the surface force balance. Here we report on a numerical study of axisymmetric thermocapillary convection in liquid bridges with deformable surfaces. The interface is determined as part of the complete solution. The influence of the capillary number (Ca), Reynolds number (Re), Prandtl number (Pr) and aspect ratio(Ar) on the dynamics is explored.

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Serially expanded flap use to treat large hairless scalp lesions

  • Shin, Dongwoo;Kim, Yong Hun;Song, Han Gyeol;Hong, Jong Won
    • 대한두개안면성형외과학회지
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    • 제20권6호
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    • pp.408-411
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    • 2019
  • Hairless scalp areas can occur due to trauma, tumors, or congenital disease. This aesthetically unpleasing condition can lead to psychosocial distress, and thin skin flaps may be prone to scarring. Treating the hairless scalp by simple excision is challenging because of skin tension. Tissue expanders are a good option for hairless scalp resurfacing. However, a single expansion may be inadequate to cover the entire defect. This report describes good results obtained using a serial resurfacing method involving re-expansion of the flap with a tissue expander to treat two patients with large lesions: one due to aplasia cutis congenital and another who underwent dermatofibrosarcoma protuberance resection. The results suggest that scalp resurfacing by serial tissue expansion using a tissue expander can be used for extensive lesions.

Numerical simulation of gas-liquid two phase flow in micro tubes

  • Sunakawa, Hideo;Teramoto, Susumu;Nagashima, Toshio
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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    • pp.341-346
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    • 2004
  • Motion of a bubble inside narrow tube is numerically studied. The numerical code assumes axi-symmetric incompressible flow field. The surface of the bubble is captured by VOF (Volume Of Fluid) method, and it is advected by MARS (Multiphase Advection and Reconstruction Scheme). Air bubble inside water is first studied, and it was found that a strong vortex, which is induced by the pressure difference caused by the surface tension, is formed at the rear part of the bubble. Then flow parameters are parametrically varied to understand the correlation between the bubble shape, the bubble velocity, and the flow parameters. The parametric study revealed that the aspect ratio of the bubble mainly depends on We number, and the oscillation of the bubble speeds is dependent on Re number.

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고성능 강섬유보강 콘크리트가 적용된 반복하중을 받는 이중 프리스트레스 콘크리트 보의 휨 거동 (Flexural Behavior of Dual Prestress Concrete Beams Using High Performance Steel Fiber Reinforced Concrete Subjected to Cyclic Loading)

  • 박대효;윤성환
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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    • pp.61-64
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    • 2004
  • This study presents results from an experimental work for two normal prestressed concrete beams and three dual prestressed concrete beams. The dual prestressed concrete beams made with normal concrete in compression zone and high performance steel fiber reinforced concrete in partial depth of tension zone. Through cyclic loading test under low frequency, structural behavior and resistance to dynamic loading for dual prestressed concrete beams are investigated. Considerable increase of crack and yield load capacity of Dual prestressed concrete beam is shown compared with normal prestressed concrete beam. In addition, re-loading and un-loading rigidity of dual prestressed concrete beam under cyclic loading are increased comparing with normal prestressed concrete beam.

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Efficient elastic stress analysis method for piping system with wall-thinning and reinforcement

  • Kim, Ji-Su;Jang, Je-Hoon;Kim, Yun-Jae
    • Nuclear Engineering and Technology
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    • 제54권2호
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    • pp.732-740
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    • 2022
  • A piping system stress analysis need to be re-performed for structural integrity assessment after reinforcement of a pipe with significant wall thinning. For efficient stress analysis, a one-dimensional beam element for the wall-thinned pipe with reinforcement needs to be developed. To develop the beam element, this work presents analytical equations for elastic stiffness of the wall-thinned pipe with reinforcement are analytically derived for axial tension, bending and torsion. Comparison with finite element (FE) analysis results using detailed three-dimensional solid models for wall-thinned pipe with reinforcement shows good agreement. Implementation of the proposed solutions into commercial FE programs is explained.

개정 사회보장기본법의 사회서비스의 의미와 개념적 긴장 (Meaning and Conceptual Tension Contained in the Definition of Social Services Prescribed by Recently Amended Framework Act on Social Security)

  • 남찬섭
    • 한국사회복지학
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    • 제64권3호
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    • pp.79-100
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    • 2012
  • 본 연구는 개정 사회보장기본법의 사회서비스가 안고 있는 개념적 긴장이 어떤 것인가를 살펴보려는 목적을 가진 것이다. 참여정부 때부터 본격적으로 사용되기 시작한 사회서비스는 적어도 네 가지의 의미를 갖고 있었는데 개정 사회보장기본법의 사회서비스는 이 중 사회적일자리와 가장 가까운 의미를 가지고 있다. 이런 의미를 가진 개정 사회보장기본법의 사회서비스는 대단히 넓은 개념으로 정의되어 있다. 하지만 이렇게 됨으로써 개정 사회보장기본의 사회서비스는 오히려 개념적 긴장을 안게 되었다. 즉, 사회서비스는 한편으로는 복지뿐만 아니라 보건, 교육, 고용, 주거, 문화, 환경 등 매우 넓은 분야를 포괄하려는 지향성을 갖지만 다른 한편으로 서비스내용을 사회복지서비스에 적합한 것들로 나열함으로써 사회서비스를 사회복지서비스에만 제한시키려는 지향성도 갖는다. 이러한 개념적 긴장은 앞으로 지속될 가능성이 높은데, 이로 인해 복지부 및 사회서비스 전달체계의 개혁이 요구되며 동시에 일관된 사회서비스를 제공하는 데 필요한 이론적 실천적 원칙의 발전이 요구된다는 점에서 사회복지학에 중대한 도전을 던져주고 있다. 이 도전에 대응하기 위해서는 미시와 거시적 접근의 소통과 공동노력이 어느 때보다 절실히 필요하다.

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