• Title/Summary/Keyword: Corner effect

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An investigation of the behavior in the corner crack propagation of Al-Alloy by the plane bending fatigue (평면 굽힘 피로하중에 의한 알루미늄 합금재의 모서리 균열 전파거동에 관한 연구)

  • 김영식;김영종
    • Journal of Advanced Marine Engineering and Technology
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    • v.8 no.1
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    • pp.49-63
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    • 1984
  • The 5086-H116 Al-Alloy plate specimens having an edge through-thickness notch were investigated to find out the characteristics of the corner crack propagation by the plane bending fatigue. The experiments were also carried out in order to clarify the change of the corner crack propagation behaviour due to the various materials and their thicknesses. In addition, the retardation effect of overload on the corner crack propagation was quantatively studied. Main results obtained are as follows; 1. In the case of estimating the crack propagation rate of the corner crack, it is more reasonable to consider the growth rate of fracture surface area than that of crack length. 2. The shape of the corner crack growing in the plane plate under the bending fatigue can be estimated. 3. The crack propagation rate increases with the increasing of the thickness and the decreasing of the Young's modulus of materials. 4. Regardless of a thickness and kind of materials of specimen, the characteristics of the corner crack propagation can be concluded. 5. The retardation effect of overload is distinct in the corner crack propagation.

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The Behavior of Retention Wall By 3-D Finite Element Method (3차원 유한요소해석에 의한 흙막이 벽체의 거동특성)

  • 이진구;장서만;전성곤;이종규
    • Proceedings of the Korean Geotechical Society Conference
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    • 2001.03a
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    • pp.347-354
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    • 2001
  • In this study, 3-D FEM analysis are carried out to investigate the effect of the corners and re-entrant corners which can't be analysed by 2-D analysis. The excavation shape is re-entrant type conditions. The wall displacement, earth pressure and effectiveness of the corner struts are investigated in the re-entrant case, The 3D analysis are peformed to evaluate the effect of various factors, such as re-entrant corner size, excavation depth, and presence of struts. The wall displacement and earth pressures are influenced the size of re-entrant corner. Therefore, the effect of re-entrant corner should be considered in the evaluation of the earth pressure and displacement of the corners. Finally, strut-support systems are not effective at the re-entrant corner.

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A Study on the Corner Effect of Fin-type SONOS Flash Memory Using TCAD Simulation (TCAD 시뮬레이션을 이용한 Fin형 SONOS Flash Memory의 모서리 효과에 관한 연구)

  • Yang, Seung-Dong;Oh, Jae-Sub;Yun, Ho-Jin;Jeong, Kwang-Seok;Kim, Yu-Mi;Lee, Sang-Youl;Lee, Hee-Deok;Lee, Ga-Won
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.25 no.2
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    • pp.100-104
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    • 2012
  • Fin-type SONOS (silicon-oxide-nitride-oxide-silicon) flash memory has emerged as novel devices having superior controls over short channel effects(SCE) than the conventional SONOS flash memory devices. However despite these advantages, these also exhibit undesirable characteristics such as corner effect. Usually, the corner effect deteriorates the performance by increasing the leakage current. In this paper, the corner effect of fin-type SONOS flash memory devices is investigate by 3D Process and device simulation and their electrical characteristics are compared to conventional SONOS devices. The corner effect has been observed in fin-type SONOS device. The reason why the memory characteristic in fin-type SONOS flash memory device is not improved, might be due to existing undesirable effect such as corner effect as well as the mutual interference of electric field in the fin-type structure as reported previously.

Effect of the Vertical Stiffness of Elastomeric Bearings on Support Reactions in Skew Bridges (탄성받침의 수직강성이 사교 지점 반력에 미치는 효과)

  • 문성권
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2003.04a
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    • pp.487-495
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    • 2003
  • Bearings at the obtuse corner are subjected to much larger vertical reactions than other bearings because of the geometric shape of skew bridges. The current relevant specifications require that additional bars should be disposed at the bottom of concrete deck slabs to deal with the large vertical reaction on bearings at the obtuse corner. In this study, new methods of reducing the magnitude of the vertical reaction on bearings at the obtuse corner by the stiffness adjustment of bearings were proposed. The basic concept of proposed methods was to redistribute support reactions by reducing the vertical stiffness of bearings at the obtuse corner showing a relatively large vertical reaction. For 45 simply supported skew bridges designed according to the current relevant specifications, the redistribution effect of vertical reactions by the stiffness adjustment of bearings was investigated. Parameters such as skew angle, girder spacing, and deck aspect ratio that affect the distribution of support reactions were considered. The results of the analyses show that the magnitude of the vertical reaction on bearings at the obtuse corner can be reduced to the levels of straight bridges by replacing the existing bearings at the obtuse corner with new ones having the value of 1/10 or 1/20 of the vertical stiffness of the existing bearings. The reduction effect of the vertical reaction on bearings at the obtuse corner increases as the girder spacing decreases and it is more pronounced when the deck aspect ratio is 2.0.

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A Study on the Effect of corner Angle on Cup Drawing (코너각이 용기에 성형에 미치는 영향에 관한 연구)

  • 김진무;유호영
    • Transactions of Materials Processing
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    • v.8 no.1
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    • pp.14-21
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    • 1999
  • Trapezoid cups and square ones have been deep-drawn to 45mm in depth. Displacements and strains have been analysed by FEM and experiment. Strains and effective strains in the corner flanges of trapezoid cups have been compared with those in square cups. The results have shown that because of shear strains on the corner flange, it is necessary to adopt effective strain for comparing strains, mean vale of effective strains in the corner flange with a corner angle of 72 degrees is narly equal to those with a corner angle of a right angle and mean value of effective strains with a corner angle of 102 degrees is smaller than those with a corner angle of a right angle.

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Three-dimensional vortex structure near a corner of a translating plate (병진운동하는 평판의 모서리에서의 3차원 와류 구조 가시화)

  • Kim, Daegyoum
    • Journal of the Korean Society of Visualization
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    • v.13 no.1
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    • pp.21-25
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    • 2015
  • Three-dimensional vortex structures in the corner region of translating normal plates are visualized experimentally with defocusing digital particle image velocimetry. Vortex formation processes for three plates with corner angle $60^{\circ}$, $90^{\circ}$, and $120^{\circ}$ are compared in order to study the effect of corner shape on vortex formation. In all cases, the self-induction of the starting vortex and its interaction with the potential flow induced by the moving plate cause the vortex to change its form dynamically after the plate starts to translate. While the vortex near a corner follows the plate in the low corner angle of $60^{\circ}$, the vortex separates early from the plate and its forward motion becomes slow in the high corner angle of $120^{\circ}$. It is also found that the starting vortex can transport inward at the corner, which depends on the corner angle.

The Analysis of Three-dimensional Oxidation Process with Elasto-viscoplastic Model

  • Lee Jun-Ha;Lee Hoong-Joo
    • Transactions on Electrical and Electronic Materials
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    • v.5 no.6
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    • pp.215-218
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    • 2004
  • This paper presents a three-dimensional numerical simulation for thermal oxidation process. A new elasto-viscoplastic model for robust numerical oxidation simulation is proposed. The three-dimensional effects of oxidation process such as mask lifting effect and corner effects are analyzed. In nano-scale process, the oxidant diffusion is punched through to the other side of the mask. The mask is lifted so the thickness of oxide region is greatly enhanced. The compressive pressure during the oxidation is largest in the mask corner of the island structure. This is because the masked area near the corner is surrounded by an area larger than the others in the island structure. This stress induces the retardation of the oxide growth, especially at the masked corner in the island structure.

Effect of corner modifications on 'Y' plan shaped tall building under wind load

  • Sanyal, Prasenjit;Dalui, Sujit Kumar
    • Wind and Structures
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    • v.30 no.3
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    • pp.245-260
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    • 2020
  • Wind load and responses are the major factors which govern the design norms of tall buildings. Corner modification is one of the most commonly used minor shape modification measure which significantly reduces the wind load and responses. This study presents a comparison of wind load and pressure distribution on different corner modified (chamfered and rounded) Y plan shaped buildings. The numerical study is done by ANSYS CFX. Two turbulence models, k-epsilon and Shear Stress Transport (SST), are used in the simulation of the building and the data are compared with the previous experimental results in a similar flow condition. The variation of the flow patterns, distribution of pressure over the surfaces, force and moment coefficients are evaluated and the results are represented graphically to understand the extent of nonconformities due to corner modifications. Rounded corner shape is proving out to be more efficient in comparing to chamfered corner for wind load reduction. The maximum reduction in the maximum force and moment coefficient is about 21.1% and 19.2% for 50% rounded corner cut.

Plating hardness and its effect to the form accuracy in shaping of corner cube on cu-plated steel plate using a single diamond tool (단결정 다이아몬드 공구에 의한 Corner Cube 가공 시, 형상정밀도에 미치는 동 도금층의 경도의 영향)

  • Lee, J.Y.;Kim, C.H.;Sea, C.W.
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.13 no.5
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    • pp.64-69
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    • 2014
  • This article presents machining experiments to assess the relationship between the profile accuracy and the workpiece hardness using a natural diamond tool on an ultra-precision diamond turning machine. The study is intended to secure a corner cube prism pattern for reflective film capable of high-quality outcomes. The optical performance levels and edge images of corner cubes having various hardness levels of the copper-coated layer on a carbon steel plate are analyzed. The hardness of the workpiece has a considerable effect on the profile accuracy. The higher the hardness of the workpiece, the better the profile accuracy and the worse the edge wear of the diamond tool.

A Study on the Stiffness of CBA(Corner Block with Anchor Bolt) Joint in Knockdown Type Table Furniture (조립식(組立式) 탁자(卓子)의 CBA접합부(接合部) 강성(剛性)에 관(關)한 연구(硏究))

  • Chung, Woo-Yang;Lee, Phil-Woo
    • Journal of the Korean Wood Science and Technology
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    • v.17 no.2
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    • pp.34-64
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    • 1989
  • Corner block with anchor bolt(CBA) joint method used in knock-down type table furniture manufacturing can reduce the packing and transporting cost. Unfortunately. it also has the disastrous defect to be loosend and unstable during the service life mainly due to fatigue and creep(repeated and prolonged loading). So 22 joint groups constructed were tested to evaluate the effect of some design factors related to the size of side rail(apron). block attachment to side rail. and the number of anchor bolt as well as the effect of the type of corner block(mitered type vs. rectangular type) Usable strength from the stiffness coefficients of each joint group were analysed with SPSS /PC+ and described as the criteria of CBA joint construction. The conclusions were as follows: The height of side rail(50, 75 and 100 mm) and the addition of polyvinyl acetate(PVAc) emulsion in the corner block attactment to side rail had the effect on raising the usable strength of CBA joint with remarkable high significance. And the effect of 2 - anchor bolts was also superior to that of 1 - bolt significantly. However. the thickness of side rail(22 mm vs. 25 mm) had no effect on the strengthening the table joint rigidity. Mitered type corner block joint appeared to he recommendable for CBA jointed table construction rather than the rectangular type one regardless of the method of block attachment to side rail. The best result identified from Duncan's multiple comparison was in the construction with 25 mm thick and 100 mm height of side rail fastened using 2 - anchor bolts in mitered type corner block. But it would be reasonable to use 22 mm thick & 75 mm high side rail and mitered corner block with PVAc emulsion & 2 bolts considering the productivity and production cost down in the MDF furniture manufacturing industries.

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