• Title/Summary/Keyword: lateral process

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Numerical Study of Double Diffusive Convection of a Stratified Fluid in an Annulus Due to Lateral Heating (환형밀폐용기내 성층화된 유체의 옆면가열에 의한 이중확산대류에 관한 수치해석)

  • 강신형;전창덕;이진호
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.7
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    • pp.1720-1730
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    • 1995
  • Finite-difference analysis was conducted to study the natural convection of a stably stratified salt-water solution in an annulus due to lateral heating. The main purpose of this study is to examine in detail the multi-layered flow structure. Calculation was thus made for R $a_{\eta}$=2*10$^{5}$ and 6.5*10$^{5}$ . Formation of layered flow structure, merging process of layers, the corresponding temperature and concentration distributions, Nusselt number variations with time are examined. Numerical results show that in each layer, the temperature profile looks 'S`-shaped and the concentration profile is uniform due to the convective mixing. The formation of the roll and the layer is governed by natural convection due to the temperature gradient and the merging process of the layer by diffusion of the concentration.ation.

Crystallization of Amorphous Silicon Films by Field-Aided Lateral Crystallization (FALC) technique at $350^{\circ}C$

  • Park, Kyoung-Wan;Cho, Ki-Taek;Choi, Duck-Kyun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.548-551
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    • 2002
  • The crystallization of amorphous silicon (a-Si) was achieved using a field aided lateral crystallization (FALC) process at 350 $^{\circ}C$. Under the influence of an electric field, Cu is found to drastically enhance the lateral crystallization velocity of a-Si. When an electric field was applied to the selectively Cu-deposited a-Si film during the heat treatment at temperature as low as 350 $^{\circ}C$, dendrite-shaped crystallization of a-Si progressed toward Cu-free region and the crystallization from negative electrode side toward positive electrode side was accelerated. We identified that 1000${\AA}$ thick a-Si film was completely crystallized by Cu-FALC process at 350 $^{\circ}C$ by TEM analysis.

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Sequential Lateral Solidification Process for Fabrication of Crystalline Silicon Thin Film Transistor (단결정 실리콘 TFT 제작을 위한 SLS 공정)

  • Lee, Youn-Jae;Pak, Jung-Ho
    • Proceedings of the KIEE Conference
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    • 2000.11c
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    • pp.461-463
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    • 2000
  • This paper presents a low temperature excimer-laser-crystallization that produces directionally solidified microstructure in Si thin films. The process involves (1) a complete melting of selected area via irradiation through a patterned mask. and (2) a precisely controlled pulse translation of the sample with respect to the mask over a distance shorter than the superlateral growth(SLG) distance. (3) lateral growth extended over a number of iterative steps. Grains that grow continuously to the vertical direction were demonstrated. We discuss sequential lateral solidification principle, experiment.

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Complete Larval Development of Novactaea pulchella (Crustacea: Decapoda: Xanthidae)

  • Ko, Hyun-Sook
    • Animal cells and systems
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    • v.10 no.1
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    • pp.7-14
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    • 2006
  • Novactaea pulchella was reared in the laboratory, from hatching to the megalopal stage at $25^{\circ}C$. The larval stage of it consists of two zoeal and one megalopal stages. The first zoea of the present study differs from that described by Terada (1990) in the setal presence of the carapace, the maxilla and the maxilliped, and the lateral process on the abdominal somite. It is reported for the first time that brachyuran zoeas belonging to a species share two types of lateral processes on the abdominal somites. They are either on the abdominal somites 2 and 3 or on abdominal somites 2 to 5. A provisional key is provided to aid the identification of the actaeine zoeas in Korea and the adjacent waters.

A Study of Failure Mechanism for Inclined Impact of PELE (PELE의 경사진 충격에 따른 파괴 메커니즘에 대한 연구)

  • Jo, Jong-Hyun;Lee, Young-Shin
    • Journal of the Korea Institute of Military Science and Technology
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    • v.15 no.5
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    • pp.712-719
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    • 2012
  • Penetrator with enhanced lateral effect(PELE) is a newconcept projectile, without dynamite and fuze. It consists of high-density jacket, closed at its rear end and filled with a low-density filling material. To study the explosion characteristics of PELE, by AUTODYN-3D code, the calculation models of projectile body and bullet target are established and the process of penetrating aluminum-2024 alloy target of PELE is simulated, and the scattering characteristics after penetrating aluminum-2024 alloy target of PELE are studied by different initial velocity. The explicit finite element analysis of PELE fragmentation was implemented with stochastic failure criterion in AUTODYN-3D code. As expansion of filling, the fragments were obtained velocities and dispersed laterally and further more enhancing the damage area largely. The number and shape of the PELE fragments were different depend on impact velocity and incidence angle of filling which fragment generated during penetration and lateral dispersion process.

A novel approach for predicting lateral displacement caused by pile installation

  • Li, Chao;Zou, Jin-feng;Li, Lin
    • Geomechanics and Engineering
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    • v.20 no.2
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    • pp.147-154
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    • 2020
  • A novel approach for predicting lateral displacement caused by pile installation in anisotropic clay is presented, on the basis of the cylindrical and spherical cavities expansion theory. The K0-based modified Cam-clay (K0-MCC) model is adopted for the K0-consolidated clay and the process of pile installation is taken as the cavity expansion problem in undrained condition. The radial displacement of plastic region is obtained by combining the cavity wall boundary and the elastic-plastic (EP) boundary conditions. The predicted equations of lateral displacement during single pile and multi-pile installation are proposed, and the hydraulic fracture problem in the vicinity of the pile tip is investigated. The comparison between the lateral displacement obtained from the presented approach and the measured data from Chai et al. (2005) is carried out and shows a good agreement. It is suggested that the presented approach is a useful tool for the design of soft subsoil improvement resulting from the pile installation.

A study on the lateral Dynamics of the Moving Web Induced by a Tilted Roller (웹 표면 수직방향으로 기우러진 롤에 의한 측 방향 웹 거동에 대한 연구)

  • Shin, Kee-Hyun
    • Journal of the Korean Society for Precision Engineering
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    • v.17 no.12
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    • pp.209-216
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    • 2000
  • The lateral behavior of the moving web is critical to the quality of the web products. The alignment of the rollers carrying the web is found to be one of important factors to the lateral behavior of the moving web. But, the study on the effect of the tilting roller in the direction of the normal to the moving web on the lateral behavior has not been reported in the literature yet. For example, the contact roller often contacts the winding roll in a tilted fashion and causes the lateral motion of the winding web, which induces the offset on the wound roll. The lateral dynamics of the moving web induced by a tilted roller in normal direction of a web is investigated in this paper. The two-dimensional dynamic model developed by Shelton is extended to investigate the effect of a titled roller in a normal direction of the moving web on the lateral motion of the moving web. New boundary conditions are developed to solve the extended model. Computer simulation study proved that the model developed can be used to predict the lateral motion of the moving web ? to a tilted roller in normal direction of the moving web. The lateral deflection is increased exponentially a the tilting angle is increased. As the length of web span is increased, the amount of lateral deflection was increased almost linearly for the same tilting angle. The lateral dynamics turned out to be almost independent to the operating tension. The model developed can be used to solve the offset problem of the staggered winding and also to design a new web guiding mechanism.

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Seismic behavior of steel frames with replaceable reinforced concrete wall panels

  • Wu, Hanheng;Zhou, Tianhua;Liao, Fangfang;Lv, Jing
    • Steel and Composite Structures
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    • v.22 no.5
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    • pp.1055-1071
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    • 2016
  • The paper presents an innovative steel moment frame with the replaceable reinforced concrete wall panel (SRW) structural system, in which the replaceable concrete wall can play a role to increase the overall lateral stiffness of the frame system. Two full scale specimens composed of the steel frames and the replaceable reinforced concrete wall panels were tested under the cyclic horizontal load. The failure mode, load-displacement response, deformability, and the energy dissipation capacity of SRW specimens were investigated. Test results show that the two-stage failure mode is characterized by the sequential failure process of the replaceable RC wall panel and the steel moment frame. It can be found that the replaceable RC wall panels damage at the lateral drift ratio greater than 0.5%. After the replacement of a new RC wall panel, the new specimen maintained the similar capacity of resisting lateral load as the previous one. The decrease of the bearing capacity was presented between the two stages because of the connection failure on the top of the replaceable RC wall panel. With the increase of the lateral drift, the percentage of the lateral force and the overturning moment resisted by the wall panel decreased for the reason of the reduction of its lateral stiffness. After the failure of the wall panel, the steel moment frame shared almost all the lateral force and the overturning moment.

The Vertical and Lateral Ordering of PDMA-b-PS Block Copolymer Thin film via Control of Relative Humidity (습도의 영향에 따른 PDMA-b-PS 친수성 블록공중합체 박막의 패턴 조절)

  • Jung, Hyun-Jung;Kim, Tae-Joon;Bang, Joon-A
    • Korean Chemical Engineering Research
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    • v.49 no.3
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    • pp.352-356
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    • 2011
  • In this paper, we prepared new type of hydrophilic block copolymers that exhibit the long-ranged lateral ordering in thin film. It was previously demonstrated that poly(ethyleneoxide-b-styrene) and poly(ethyleneoxide-b-metharylate-b-styrene) block copolymer thin films have a high degree of lateral ordering after solvent annealing process. In these cases, the relative humidity plays an important role in long-ranged lateral ordering. However, the origin of the humidity effect on the orders of these hydrophilic block copolymers is not fully understood. To investigate the effect of the humidity further, we prepared other hydrophilic poly(N,N-dimethylacrylamide-b-styrene)(PDMA-b-PS) block copolymers via RAFT polymerization. As with PEO-containing block copolymers, PDMA-b-PS block copolymers exhibit the long-ranged lateral ordering after solvent annealing process.

Electrical characteristics of lateral poly0silicon field emission triode using LOCOS process

  • Lee, Jae-Hoon;Lee, Myoung-Bok;Park, Dong-Il;Ham, Sung-Ho;Lee, Jong-Hyun;Lee, Jung-Hee
    • Journal of Korean Vacuum Science & Technology
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    • v.3 no.1
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    • pp.38-42
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    • 1999
  • Using the LOCOS process, we have fabricated the lateral type polysilicon field emission triodes with poly-Si/oxide/Si structure and investigated their current-voltage characteristics for three biasing modes of operation. The fabricated devices exhibit excellent electrical performances such as a relatively low turn-on anode voltage of 14 V at VGC = 0V, a stable and high emission current of 92${\mu}$A/triode over 90 hours, a small gate leakage current of 0.23 ${\mu}$A/triode and an outstanding transconductance of 57${\mu}$S/5triodes at VGC = 5V and VAC = 26V. these superior electrical operation is believed to be due to a large field enhancement effect, which is related to the sharp cathode tips produced by the LOCOS process as well as the high aspect ratio (height /radius ) of the cathode tip end.

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