• 제목/요약/키워드: rod bar

검색결과 79건 처리시간 0.021초

Ligand Binding energy of CdS/ZnS various interfaces: ab-initio study intimately related with anisotropic CdS/ZnS quantum rod growth

  • Jeong, Incheol
    • EDISON SW 활용 경진대회 논문집
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    • 제4회(2015년)
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    • pp.292-295
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    • 2015
  • The effect of Ligand Binding energy in quantum rod (CdS/ZnS) plays a critical role in anisotropic growth. As mimicking large chain of ligands and using the head of the chain, I plan to bind the quantum rod and ligands so that it can grow well consequently. So the ultimate goal of this study is on how ligand binding can affect the growth of this quantum rod. There are preferred surfaces between the quantum rod and ligands, and we empirically know that ligands which bind the quantum rod; Phosphoric oxide (PO), Phosphoric acid(PA), Carboxylic acid(CA), Trimethylamine(TMA), have strong tendency to be attached on the surfaces of CdS/ZnS; ($11{\bar{2}}0$), ($10{\bar{1}}0$), ($000{\bar{1}}$), (0001). I virtually bond the surface and the ligands, and calculated the ligand binding energy after optimizing their structure, utilizing EDISON simulator. After all, I figured out how they are linked each other and how the quantum rod grows.

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원형봉에서 정사각재 인발공정의 유한요소 해석 (Finite Element Analysis for the Drawing of Square Rod from Round Bar)

  • 최영;김호창;김병민
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1998년도 춘계학술대회논문집
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    • pp.205-209
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    • 1998
  • Unlike the drawing of round section from round bar, the shaped drawing like polygonal section is known to have influence not only drawing stress but also comer filling. Therefore, this study analyze the drawing process of suqare rod from round bar using nonsteady state rigid-plastic FEM. To investigate effects of process variables of the drawing process of square rod from round bar, FE-simulations with variety of reduction in area and semi-die angle for a given frictional condition have been conduction. By this results, it has to suggest optimal process condition on the drawing stress and the comer filling. In addition, it has determined forming limit considering necking and bulging.

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강소성 유한요소법을 이용한 원형봉에서 정사각재 인발공정에 관한 연구 (A Study on the Drawing Process of Square Rod from Round Bar by Using the Rigid-Plastic Finite Element Method)

  • 김호창;김용철;최영;김병민
    • 한국정밀공학회지
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    • 제15권11호
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    • pp.145-151
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    • 1998
  • Unlike the drawing of round section from round bar, the shaped drawing like polygonal section is known to have influence not only drawing stress but also corner filling. Therefore. this study analyze the drawing process of suqare rod from round bar using nonsteady state rigid-plastic FEM. To investigate effects of process variables of the drawing process of square rod from round bar, FE-simulations with variety of reduction in area and semi-die angle for a given frictional condition have been conducted. By this results, it has to suggest optimal process condition on the drawing stress and the corner filling. In addition, it has determined forming limit considering necking and bulging.

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유한 요소법을 이용한 다단 선재 압연의 3차원 정상 상태 변형 해석 (Finite Element Analysis of 3 Dimensional Steady State Deformation in Multi-stand Rod and Bar Rolling)

  • 김홍준;김태효;황상무
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1998년도 춘계학술대회논문집
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    • pp.134-137
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    • 1998
  • Caliber design in bar and rod rolling depends on the designer's experience, which in general is acquired through costly trial-and-error process. As a prerequisite for developing a scientific approach to caliber design, we present a finite element model to simulate 3-D deformation of bars and rods occurring in multi-pass sequence. The results are compared with measurements obtained from POSCO for to assess the solution accuracy. The comparison shows that the simulation results agree well experiments.

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접착제에 따른 Glued-in Rod 접합부 인발성능에 관한 실험 연구 (Experimental Study on Pull-out Strength of Glued-in Rods Connection according to Adhesive)

  • 박금성;오근영
    • 한국건축시공학회지
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    • 제22권2호
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    • pp.149-160
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    • 2022
  • 본 연구에서는 국내에서 생산되는 목재와 접착제를 활용한 Glued-in rod 접합부의 인발성능을 평가하고자 접착제의 종류, 철근의 매입깊이 및 매입방향을 고려한 인발성능 실험연구를 수행하였다. 실험결과, 액상형 접착제 사용 실험체가 더 우수한 인발성능을 보여주었으며, 철근의 매입깊이가 길어질수록 철근의 항복을 먼저 유도하여 높은 최대 인발하중을 보여주었다. 인발성능 실험결과를 통하여 철근의 항복강도보다 접착제의 부착강도를 더 강하게 설계하는 것이 유리한 Glued-in rod 접합부 설계식을 제안하였으며, 접착제의 부착강도의 시공오차를 고려한 보정계수 0.75 또한 제안하였다.

배출봉을 이용한 정밀여과용 관형 모듈의 투과특성 (Permeation Characteristics of the Microfiltration Tubular Module using the Discharged Rod)

  • 정건용;최정규
    • 멤브레인
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    • 제19권4호
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    • pp.285-290
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    • 2009
  • 공칭 세공크기 $0.1\;{\mu}m$이고 내경이 5 mm인 정밀여과용 관형 분리막 내에 자체 설계한 배출봉을 삽입하여 막오염 감소효과에 따른 투과유속을 측정하였다. 원료용액으로는 에멀젼 상태의 dioctyl tinoxide (DOTO) 입자를 사용하였으며 0.5 wt%까지 농도를 변화시키면서 1.6 bar 이내에서 운전하였다. 배출봉의 효과는 매 실험마다 배출봉을 삽입한 경우와 사용하지 않은 경우의 투과유속을 비교하여 평가하였다. 배출봉을 사용할 경우 운전압력 1.6 bar에서 최대 20%의 투과유속이 향상되었다. 또한 DOTO 농도가 증가함에 따라서 배출봉에 의한 투과유속 향상효과는 크게 나타났으며 0.5 wt% 농도에서 43%까지 투과유속이 향상되었다.

수송기계용 Stabilizer Link의 광센서를 이용한 부품성능평가 (Analyzing Materials Property using Optical Sensing Technique of Stabilizer Link for Automobile Parts)

  • 남기우;우영만;오정환;문창권
    • 동력기계공학회지
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    • 제14권6호
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    • pp.47-53
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    • 2010
  • A stabilizer link connects the stabilizer bar to the lower arm of the suspension. When a vehicle is turning, lateral forces from the tire are transmitted through the stabilizer link into the stabilizer bar. The stabilizer bar will twist, thus adding rigidity to the vehicle body. In this study, the stabilizer link body was manufactured by using composite material with POM-GF25%. Therefore, the strength evaluation of stability link body with composite material carried out from tensile, wear and fatigue test. The tensile strength between the stability link body with composite material and the rod with knurling was the largest of four types of rod. In Analyzing materials property using optical sensing technique of stabilizer link for automobile parts, its has been identified the safety.

사각재 인발 공정의 코너채움에 관한 연구 (A Study on the Corner Filling in the Drawing of the Rectangular Rod)

  • 김용철;김영식;김병민
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1999년도 압출 및 인발 심포지엄
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    • pp.56-59
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    • 1999
  • In the present study, in order to investigate the effect of the corner filling in the drawing of the rectangular rod from a round bar, the drawing of the square rod from a round bar has been simulated by using rigid-plastic finite element method and artificial neural network has been introduced to reduce the number of simulation. The experimental investigation has been also implemented to verify the efficiency of the application of results of present and previous study. According to the results of present and pervious study, the combination of semi-die angle gives a great effect on the corner filling in case of the irregular shaped drawing process, but, in case of the regular shaped drawing process, the main process variable on the corner filling is reduction in area.

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고강도 육각 이형 인발 다이스에 관한 연구 (A study on the hexagonal drawing dies for the high strength materials)

  • 권혁홍;유동진;이정로;이원복
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.1410-1413
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    • 2003
  • Drawing is a basic plastic deformation method and productive manufacturing process make wire. rod and variety section geometry bar. Study for the rod drawing process of rod was researched long littles. but non-axisymmetric drawing process is weak. So metal flow is very irregular in non-axisymmetric drawing process and difficult to define about material deformation generally. In this paper, to solve material deformation, use finite element method and then define suitable shape for rod to hexagonal drawing dies. And research corner filling rate and surface roughness for the high strength steel hexagonal bar produced defined dies.

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Adjustment of Roll Gap for the Dimension Accuracy of Bar in Hot Bar Rolling Process

  • Kim, Dong-Hwan;Kim, Byung-Min;Lee, Youngseog
    • International Journal of Precision Engineering and Manufacturing
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    • 제4권1호
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    • pp.56-62
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    • 2003
  • The objective of this study is to adjust the roll gap for the dimension accuracy of bar in hot bar rolling process considering roll wear. In this study hot bar rolling processes for round and oval passes have been investigated. In order to predict the roll wear, the wear model is reformulated as an incremental form and then wear depth of roll is calculated at each deformation step on contact area using the results of finite element analysis, such as relative sliding velocity and normal pressure at contact area. Archard's wear model was applied to predict the roll wear. To know the effects of thermal softening of DCI (Ductile Cast Iron) roll material according to operating conditions, high temperature micro hardness test is executed and a new wear model has been proposed by considering the thermal softening of DCI roll expressed in terms of the main tempering curve. The new technique developed in this study for adjusting roll gap can give more systematically and economically feasible means to improve the dimension accuracy of bar with full usefulness and generality.