• 제목/요약/키워드: details

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단부 보강에 따른 U-플랜지 트러스 보의 구조 내력에 관한 실험 연구 (Experimental Study on the Structural Capacity of the U-Flanged Truss Steel Beam With Reinforced End by Steel Plates)

  • 오명호;김영호
    • 한국공간구조학회논문집
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    • 제20권2호
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    • pp.31-38
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    • 2020
  • U-flanged truss beam is composed of u-shaped upper steel flange, lower steel plate of 8mm or more thickness, and connecting lattice bars. Upper flange and lower plate are connected by the diagonal lattice bars welded on the upper and lower sides. In this study, the details of delayed buckling of lattice members were developed through reinforcement of the end section, in order to improve structural capacity of U-flanged Truss Steel Beam. To verify the effects of these details, the simple beam experiment was conducted. The maximum capacity of all the specimens were determined by the buckling of the lattice. The vertical reinforced details of the ends with steel plates, rather than the details reinforced with steel bars, are confirmed to be a valid method for enhancing the structural capacity of the U-flanged Truss beam. In addition, U-flanged Truss Steel Beam with reinforced endings with steel plates can exhibit sufficient capacity of the lattice buckling by the formulae according to Korean Building Code (KBC, 2016) and Eurocode 3.

An Adaptive Histogram Equalization Based Local Technique for Contrast Preserving Image Enhancement

  • Lee, Joonwhoan;Pant, Suresh Raj;Lee, Hee-Sin
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제15권1호
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    • pp.35-44
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    • 2015
  • The main purpose of image enhancement is to improve certain characteristics of an image to improve its visual quality. This paper proposes a method for image contrast enhancement that can be applied to both medical and natural images. The proposed algorithm is designed to achieve contrast enhancement while also preserving the local image details. To achieve this, the proposed method combines local image contrast preserving dynamic range compression and contrast limited adaptive histogram equalization (CLAHE). Global gain parameters for contrast enhancement are inadequate for preserving local image details. Therefore, in the proposed method, in order to preserve local image details, local contrast enhancement at any pixel position is performed based on the corresponding local gain parameter, which is calculated according to the current pixel neighborhood edge density. Different image quality measures are used for evaluating the performance of the proposed method. Experimental results show that the proposed method provides more information about the image details, which can help facilitate further image analysis.

조립식 물량저감 중공 철근콘크리트 교각의 성능평가 (Performance Assessment of Hollow Precast Segmental Bridge Columns with Reinforcement Details for Material Quantity Reduction)

  • 김태훈;박동규;이재훈;신현목
    • 한국지진공학회논문집
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    • 제20권1호
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    • pp.33-43
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    • 2016
  • This study investigates the performance of hollow precast segmental bridge columns with reinforcement details for material quantity reduction. The proposed triangular reinforcement details are economically feasible and rational, and facilitate shorter construction periods. The precast segmental bridge columns provides an alternative to current cast-in-place systems. We tested a model of hollow precast segmental bridge columns under a constant axial load and a quasi-static, cyclically reversed horizontal load. We used a computer program, Reinforced Concrete Analysis in Higher Evaluation System Technology (RCAHEST), for analysis of reinforced concrete structures. The used numerical method gives a realistic prediction of performance throughout the loading cycles for hollow precast segmental bridge column specimens investigated. As a result, proposed reinforcement details for material quantity reduction was equal to existing reinforcement details in terms of required performance.

Bond and ductility: a theoretical study on the impact of construction details - part 1: basic considerations

  • Zwicky, Daia
    • Advances in concrete construction
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    • 제1권1호
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    • pp.103-119
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    • 2013
  • The applicability of limit analysis methods in design and assessment of concrete structures generally requires a certain plastic deformation capacity. The latter is primarily provided by the ductility of the reinforcement, being additionally affected by the bond properties between reinforcing steel and concrete since they provoke strain localization in the reinforcement at cracks. The bond strength of reinforcing bars is not only governed by concrete quality, but also by construction details such as bar ribbing, bar spacing or concrete cover thickness. For new concrete structures, a potentially unfavorable impact on bond strength can easily be anticipated through appropriate code rules on construction details. In existing structures, these requirements may not be necessarily satisfied, consequently requiring additional considerations. This two-part paper investigates in a theoretical study the impacts of the most frequently encountered construction details which may not satisfy design code requirements on bond strength, steel strain localization and plastic deformation capacity of cracked structural concrete. The first part introduces basic considerations on bond, strain localization and plastic deformation capacity as well as the fundamentals of the Tension Chord Model underlying the further investigations. It also analyzes the impacts of the hardening behavior of reinforcing steel and concrete quality. The second part discusses the impacts of construction details (bar ribbing, bar spacing, and concrete cover thickness) and of additional structure-specific features such as bar diameter and crack spacing.

수리형태학적 Laplacian 연산을 이용한 새로운 동영상 Detail 추출 기법 (A New Details Extraction Technique for Video Sequence Using Morphological Laplacian)

  • 김희준;어진우
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1998년도 추계종합학술대회 논문집
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    • pp.911-914
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    • 1998
  • In this paper, the importance of including small image features at the initial levels of a progressive second generation video coding scheme is presented. It is shown that a number of meaningful small features called details shouuld be coded in order to match their perceptual significance to the human visual system. We propose a method for extracting, perceptually selecting and coding of visual details in a video sequence using morphological laplacian operator and modified post-it transform is very efficient for improving quality of the reconstructed images.

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여성복 디테일 종류에 따른 감성과 상대적 영향력 (Effects of Design Detail Types of Ladies Wear on Sensibility and Emotion)

  • 정경용;나영주
    • 한국의류산업학회지
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    • 제7권2호
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    • pp.162-168
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    • 2005
  • The pictures of design details, such as collar type, sleeve type, skirt type, and skirt length, and color tone were evaluated by 377 persons in terms of sensibility and emotion. The data were analyzed by SPSS using ANOVA and Factor analysis to find out the most effective types of details on consumer's sensibility and emotion, and the methods were introduced. The most effective type is skirt length on sensibility and emotion of women's dress. The second type is different according to sensibility and emotion. Sensibility and emotion were composed of three concept: contemporary, mature and character. Sleeve type is second determinant to contemporary concept, and color tone is to mature concept, collar type is to character concept. 41 each details of design were positioned into 3D-concept space to connect each detail type and fashion concept of women's dress.

고강도 철근 및 고강도 콘크리트를 사용한 보-기둥 접합부의 연성거동 (Ductile Behavior of High Strength Reinforced Concrete Beam-Column Joint)

  • 이정한;유영찬;이원호;정헌수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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    • pp.537-540
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    • 1999
  • The primary objective of this study is to make a contribution to the construction of 40~60 story R/C high rise building by developing the reinforcing details which can improve the seismic performance of high-strength (f'c=700kg/$\textrm{cm}^2$, fy=4000, 8000kg/$\textrm{cm}^2$) R/C beam-column joints. And the purpose of this study is to investigate experimentally the effect of load history on the total energy dissipation capacity of reinforced concrete flexural members. The reinforcing details which can make beam plastic hinging zones moved and spreaded from the column face is proposed to insure the ductile behavior of high-strength RC beam-column joints. The intermediate reinforcement which is horizontally anchored by interlinking each intermediate reinforcements is proposed and tested to examine the mechanical performance of proposed details. Main variables are the shape of the intermediate reinforcements and yield strength of rebars. From the test results, the newly proposed intermediate reinforcement details can move and spread the beam plastic hinging zone about 1.0d from the column face.

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구조 상세가 다른 벽체의 변형성능과 반응수정계수 (Response Modification Factor and Deformability for Structural Walls Designed with Different Details)

  • 오영훈;한상환
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.959-964
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    • 2001
  • This study investigates the seismic performance of bearing walls with rectangular sectional shape and specific details of reinforcements developed for 10 to 20-story apartment buildings in Korea. To investigate seismic behavior of structural walls, several specimens were experimented by author and laboratory test results by other researchers were collected and analysed. Structural behaviors of walls were evaluated by means of ductility, deformation, and strength capacities. For this purpose, thirty six specimens having different Properties such as aspect ratios and details were considered. Based on the results of this study, deformability of the walls with specific details is discussed. Also this study compares the response modification factor(R) for the bearing wall systems in seismic design provisions between Korea and United States.

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고강도 철근 및 고강도 콘크리트를 사용한 보-기둥 접합의 비선형 거동 (Inelastic Behavior of High Strength Reinforced Concrete Beam-Column Joint)

  • 이정한;조중현;유영찬;이원호;정헌수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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    • pp.547-552
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    • 1999
  • The purpose of this study is to make a contribution to the construction of 40∼60 story R/C high rise building by developing the reinforcing details which can improve the seismic performance of high-strength (f'c=700㎏/㎠, fy=4000, 8000㎏/㎠) R/C beam-column joints. The reinforcing details which can make beam plastic hinging zones moved and spreaded from the column face is proposed to insure the ductile behavior of high-strength RC beam-column joints. The intermediate reinforcement which is vertically anchored by interlinking each intermediate reinforcements is proposed and tested to examine the mechanical performance of proposed details. Main variables are the shape of the intermediate reinforcements and yield strength of rebars. From the test results, the newly proposed intermediate reinforcement details can move and spread the beam plastic hinging zone about 1.0d from the column face.

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겹침이음길이 및 구속 철근에 따른 헤드철근의 구조적 성능에 관한 실험적 연구 (An Experimental Study on the Structural Performance of Headed Bars by Lap Length and Confinement Details)

  • 유호일;이용택;김승훈;채서호;반병열
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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    • pp.286-289
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    • 2006
  • Headed bars have used to the anchoring of the tension or compression longitudinal bars and of the shear reinforcing bars. Recently, lap splices of headed bars are attempted to the joints of precast concrete members and to the connections between old and new concrete members. Previous Michael's experimental research showed that confinement details had an effect on the lap splice performances of headed bars. In this study, the lap splice performances of headed bars(D25) with lap length and confinement details are evaluated through the experimental works. Four specimens, of which variables were the lap length of headed bar and the type of confine details, were tested for the performance evaluation on lap splice. Test results show that the lap length confinement reinforcement improve the performance of lap splice.

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