• 제목/요약/키워드: Layered method

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새로운 방법으로 제조된 적층구조 $BaTiO_3$ 박막의 전기적 특성에 관한 연구 (Study on the electric properties of layered $BaTiO_3$ films prepared new stacking method)

  • 송만호;이윤희;한택상;오명환;윤기현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1995년도 하계학술대회 논문집 C
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    • pp.1129-1132
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    • 1995
  • In the preparation of the layered $BaTiO_3$ thin films with high performance, the new stacking method using the continuous cooling of the substrate was introduced. Amorphous/polycrystalline $BaTiO_3$ layered structure was confirmed by SEM and index of refraction. The layered $BaTiO_3$ thin films formed by the new stacking method showed such a high dielectric constant that the layered structure could not be explained by a stacking structure of the two defined layers but could only be explained by multi-layered structure, i.e. amorphous/micro crystalline/polycrystalline structure. The layered $BaTiO_3$ thin film with a thickness of 240 nm showed higher capacitance per unit area and breakdown strength than the double layered $BaTiO_3$ thin film prepared by the conventional stacking method. And well defined ferroelectric hysteresis leer was observed in the layered $BaTiO_3$ thin film with a thickness of 200 nm.

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다층 지반의 2차원 압밀 수치해석 II (2-D Consolidation Numerical Analysis of Multi_Layered Soils (II))

  • 류권일;김팔규;구기욱;남상규
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 가을 학술발표회 논문집
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    • pp.665-672
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    • 2000
  • The problems of discontinuous layer interface are very important in the algorithm and programming for the analysis of multi-layered consolidation using a numerical analysis, finite difference method(F.D,M.). Better results can be obtained by the process for discontinuous layer interface, since it can help consolidation analysis to model the actual ground Explicit method is simple for analysis algorithm and convenient for use except for applying the operator Crank-Nicolson method represents implicit method, which have different analysis method according to weighting factor. This method uses different algorithm according to dimension. And, this paper uses alternative direction implicit method. The purpose of this paper provides an efficient computer algorithm based on numerical analysis using finite difference method which account for multi-layered soils with confined aquifer to determine the degree of consolidation and excess pore pressures relative to time and positions more realistically.

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유한요소-경계요소 조합에 의한 지반-말뚝 상호작용계의 주파수 응답해석

  • 김민규;조석호;임윤목;김문겸
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2000년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring
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    • pp.443-450
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    • 2000
  • In this study a numerical method for soil-pile interaction analysis buried in multi-layered half planes is presented in frequency domain using FE-BE coupling. The total soil-pile interaction system is divided into two parts so called far field and near field beam elements are used for modeling a pile and coupled with plain strain elements for soil modeling. Boundary element formulation using the multi-layered dynamic fundamental solution is adopted to the far field and coupled with near field modeled by finite elements. In order to verify the proposed soil-pile interaction analysis method the dynamic responses of a pile on multi-layered dynamic fundamental solution is adopted to the far field and coupled with near field modeled by finite elements. In order to verify the proposed soil-pile interaction analysis method the dynamic responses of a pile on multi-layered half-planes are performed and compared with experiment results. Through this developed method the dynamic response analysis of a pile buried in multi-layered half planes can be calculated effectively in frequency domain.

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다층 지반의 2차원 압밀 수치해석 (2-D Consolidation Numerical Analysis of Multi_Layered Soils)

  • 김팔규;류권일;남상규;이재식
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 봄 학술발표회 논문집
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    • pp.467-474
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    • 2000
  • The application of Terzaghi's theory of consolidation for analysing the settlement of multi-layered soils is not strictly valid because the theory involves an assumption that the soil is homogeneous. The settlement of stratified soils with confined aquifer can be analysed using numerical techniques whereby the governing differential equation is replaced by 2-dimensional finite difference approximations. The problems of discontinuous layer interface are very important in the algorithm and programming for the analysis of multi-layered consolidation using a numerical analysis, finite difference method(F.D.M.). Better results can be obtained by the process for discontinuous layer interface, since it can help consolidation analysis to model the actual ground The purpose of this paper provides an efficient computer algorithm based on numerical analysis using finite difference method(F.D.M) which account for multi-layered soils with confined aquifer to determine the degree of consolidation and excess pore pressures relative to time and positions more realistically.

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다층 구조 도파관 소자 단면에의 무반사 코팅 설계 (Design of antireflection coationgs on the facets of a multilayered structure waveguide device)

  • 김용곤;김부균;주흥로
    • 한국통신학회논문지
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    • 제21권7호
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    • pp.1850-1860
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    • 1996
  • We present the results for the design ofantireflection (AR) coatings on facets of a multilayered structure waveguide device. The method, whose results agree very well with the reusults of the rigorous method in the case of a symmetric three layer structure deveice, is extended for the design of AR coatings on the facets of a multilayered structure waveguide device. the field profile in a multilayered structure waveguide necessary for the use of the extended method is obtained from the transfer matrix method. The virtual four layered structure method (VFLM) is proposed to reduce the time for the design ofAR coatings because the time for the design of AR coatings using the extended method increases as the number of layers increases. The optimum coating parameters and tolerance mapsfor two different six layered waveguide devices in Ref. [9] and [10] are obtained using the extendedmethod and the VFLM,and for the three different cases approximated as three layered waveguide devices to compare the results of each case. The results of the VFLM are similar to those of the extended methodcompared to those of the three layered structure waveguide. The main reason for the above results is that the field profile in the device calculated usingthe VFLM is similar to that calculated using the extended method compared to that for three layered structure wavegjide. We conclude that the extended method or VFLM should be used for the design of AR coatings on facets of a deice required for the facet reflectivity less than 10$^{-3}$ such as a semiconductor otical amplifier.

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Multiple-Layered Colloidal Assemblies via Dipping Method with an External Electric Field

  • Im, Sang-Hyuk;Park, O-Ok;Kwon, Moo-Hyun
    • Macromolecular Research
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    • 제11권2호
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    • pp.110-114
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    • 2003
  • When using the dipping method for crystal formation, mono-layered colloidal crystal structures depend upon the lift-up rate of a glass substrate. The mono-layered colloidal crystals showed the highest quality when the glass substrate was raised at a rate of 3 mm/min at 25 $^{\circ}C$ in a 1 wt% polystyrene colloidal suspension (ethanol medium). In addition, in order to obtain multiple-layered colloidal crystals, an external electric Held was introduced. Multiple-layered colloidal crystals were successfully obtained via this method. The colloidal particles were well ordered over large areas and assembled into a homogeneous structure.

Layered finite element method in cracking and failure analysis of RC beams and beam-column-slab connections

  • Guan, Hong;Loo, Yew-Chaye
    • Structural Engineering and Mechanics
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    • 제5권5호
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    • pp.645-662
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    • 1997
  • A nonlinear semi-three-dimensional layered finite element procedure is developed for cracking and failure analysis of reinforced concrete beams and the spandrel beam-column-slab connections of flat plates. The layered element approach takes the elasto-plastic failure behaviour and geometric nonlinearity into consideration. A strain-hardening plasticity concrete model and a smeared steel model are incorporated into the layered element formulation. Further, shear failure, transverse reinforcement, spandrel beams and columns are successfully modelled. The proposed method incorporating the nonlinear constitutive models for concrete and steel is implemented in a finite element program. Test specimens including a series of reinforced concrete beams and beam-column-slab connections of flat plates are analysed. Results confirm the effectiveness and accuracy of the layered procedure in predicting both flexural and shear cracking up to failure.

서비스 맞춤형 컨테이너를 위한 블록 입출력 히스토리 학습 기반 컨테이너 레이어 파일 시스템 선정 기법 (A Method of Selecting Layered File System Based on Learning Block I/O History for Service-Customized Container)

  • 용찬호;나상호;이필우;허의남
    • 정보처리학회논문지:컴퓨터 및 통신 시스템
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    • 제6권10호
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    • pp.415-420
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    • 2017
  • OS-level의 가상화 기술은 애플리케이션을 배포하기 위한 새로운 패러다임으로, 기존의 가상화 기술인 가상 머신을 대체할 수 있는 기술로서 주목받고 있다. 특히 컨테이너는 기존의 리눅스 컨테이너에 유니온 마운트 포인트(Union Mount Point) 와 레이어 구조의 이미지를 적용함으로써 보다 빠르고 효율적인 애플리케이션의 배포가 가능하다. 이러한 컨테이너의 특징들은 스냅숏 기능을 제공하는 레이어 구조의 파일 시스템에서만 사용될 수 있으며, 애플리케이션의 특징에 따라 적절한 레이어 파일 시스템을 선택하는 것이 요구된다. 따라서 본 논문에서는 대표적인 레이어 파일 시스템들의 특징을 조사한 뒤, 레이어 파일 시스템의 동작 원리인 Allocate-on-Demand 및 Copy-up 방식에 따른 파일 시스템의 쓰기 성능 평가를 수행한다. 또한 각 레이어 파일 시스템 방식의 블록 입출력 사용 데이터를 학습한 인공 신경망을 통해 임의의 애플리케이션에 대해 적합한 레이어 파일 시스템 방식을 결정하는 방법을 제시하고 이에 대한 타당성을 검토한다.

다층토 지반에서 매입말뚝(SIP)의 신뢰성 연구 (The Reliability of SIP Pile in Layered Ground)

  • 이민선;황의석;이봉열;김학문
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 봄 학술발표회 논문집
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    • pp.567-574
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    • 2002
  • Rapid urbanization of many cities require large scale constructions such as high rise buildings in difficult ground conditions. SIP(Soil-cement Injected Precast pile) type piles are tile most popular choice of foundation method in soft ground as well as layered ground in many cities in Korea since SIP offer negligible amount of noise and vibration. But SIP method of construction provide wide range of pile capacity depending on the construction method, equipment, ground conditions and quality control method etc. Therefore this paper intend to investigate the reliability of SIP pile in layered ground through a comparison of existing design formulars and SIP pile load test.

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샌드위치형 다층 감쇠보의 강제진동 응답 해석 (Forced Vibration Analysis of Multi-Layered Damped Sandwich Beam)

  • 원성규;정의봉
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 추계학술대회논문집
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    • pp.608-611
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    • 2005
  • In this paper the general equation of motion of damped sandwich beam including arbitrary viscoelastic material layer was derived based on the equation presented by Mead and Markus. The equation of motion of n-layered sandwich beam was represented by (n+3)th order ordinary differential equation. It was verified that the general equation of motion derived in this paper could represent the equations of motions for single-layered, three-layered, five-layered and multi-layered damped beam. Finite element method for the arbitrary-layered damped beam was formulated and programmed using higher order shape functions. Several numerical examples were implemented to show the effects of damped material.

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