• Title/Summary/Keyword: Analytical mode

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NUMERICAL SIMULATION OF COASTAL INUNDATION OVER DISCONTINUOUS TOPOGRAPHY

  • Yoon, Sung-Bum;Cho, Ji-Hoon
    • Water Engineering Research
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    • v.2 no.2
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    • pp.75-87
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    • 2001
  • A new moving boundary technique for leap-frog finite difference numerical mode is proposed for the resonable simulation of coastal inundation over discontinuous topography. The new scheme improves the moving boundary technique developed by Imamura(1996). The present scheme is tested using the analytical solution of Thacker(1981) for the case of free oscillation with moving boundary in a parabolic bowl. Finally, a numerical simulation is conducted for the flooding over a tidal barrier constructed on a simple concave geometry. A general feature of inundation over a discontinuous topography is well described by the numerical model.

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Characterization of Metal-insert Waveguide E-plane Structures (금속판이 E-면에 삽입된 도파판의 특성 측정에 관한 연구)

  • 박용선
    • Proceedings of the Optical Society of Korea Conference
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    • 1990.02a
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    • pp.257-259
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    • 1990
  • In the design of waveguide E-plane bandpass filter, it is very important to characterize the K-inverters. In the analytical method. losses arising from the metal and the dielectric are ignored for the simplicity of design process. In this paper, based on the new measurement method, characteristics of inverters are measured and compared with those calculated based on mode-matching analysis.

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An Experimental Study on the Free Vibration of the Steel and Composite Cylindrical Shells with Simply Supported Edge Conditions (단순지지된 Steel 및 복합재료 원통셸의 진동에 대한 실험적 고찰)

  • 이영신;최명환;길기남;송근영
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1998.04a
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    • pp.334-339
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    • 1998
  • The free vibration analysis of the simply supported steel and composite cylindrical shells are investigated. The natural frequencies and mode shapes of the shell are experimentally obtained by impact testing using an impact hammer and an accelerometer. The effects of the material and geometry on the vibrational characteristics of the shell are examined. The experimental results are compared with the analytical and a finite element results. They showed good agreement with each other.

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고상미량추출장치(SPME)를 이용한 유류 오염 지하수 평가 기법 연구

  • 조현정;백기태;박지연;양지원
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2001.09a
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    • pp.148-150
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    • 2001
  • Solid-phase microextraction (SPME) was investigated to understand the BTEX extraction behavior of SPME in groundwater. Analytical procedure was conducted In both conventional and headspace mode. And the conventional direct extraction method and the headspace analysis method were compared. Data obtained with direct and headspace SPME were very similar and showed successful results. In headspace analysis, the linearity was better and RSD (relative standard deviation, %) was smaller than direct extraction.

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Strut-and-Tie Model for Shear Strength of R/C Columns (철근콘크리트 기둥의 전단강도 산정을 위한 스트럿 타이 모델)

  • 이수곤;하태훈;홍성걸
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.04a
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    • pp.591-596
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    • 1999
  • Current design methods as well as the majority of the previous researches for shear strength of the reinforced concrete are based on empirical method. There is a need to propose the rational models based on analytical approach. This paper presents the modified strut-and-tie model for reinforced concrete columns, under axial compression, shear, and flexural moment, considering tensile strength of concrete. Using this model, the strength and the failure mode of R/C columns are investigated, and the proposed models are compared with test data available in the literature.

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An Estimate of the Yield Displacement of Coupled Walls for Seismic Design

  • Hernandez-Montes, Enrique;Aschheim, Mark
    • International Journal of Concrete Structures and Materials
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    • v.11 no.2
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    • pp.275-284
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    • 2017
  • A formula to estimate the yield displacement observed in the pushover analysis of coupled wall lateral force-resisting systems is presented. The estimate is based on the results of an analytical study of coupled walls ranging from 8 to 20 stories in height, with varied amounts of reinforcement in the reinforced concrete coupling beams and walls, subjected to first-mode pushover analysis. An example illustrates the application of these estimates to the performance-based seismic design of coupled walls.

Stability Analysis of the Hydraulic System for a Dual Arm Work Module (이중 암 작업모듈 유압시스템의 안정성 해석)

  • Lee, Jae-Cheon
    • Proceedings of the KSME Conference
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    • 2001.06b
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    • pp.283-288
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    • 2001
  • This study provides analytical evaluation of the Dual-Ann Work Module. The current hydraulic system was modeled using the HyPneu and analyzed to find the cause of the instability. The cause of the instability was determined to be primarily an interacting involving the pilot operated check valves and the counterbalance valves for fail safe mode of operation. A new design concept was developed to eliminate the potential for unstable operation while adequately meeting the need for a fail-safe feature.

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A novel model of a nonlocal porous thermoelastic solid with temperature-dependent properties using an eigenvalue approach

  • Samia M. Said
    • Geomechanics and Engineering
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    • v.32 no.2
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    • pp.137-144
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    • 2023
  • The current article studied wave propagation in a nonlocal porous thermoelastic half-space with temperature-dependent properties. The problem is solved in the context of the Green-Lindsay theory (G-L) and the Lord- Shulman theory (L-S) based on thermoelasticity with memory-dependent derivatives. The governing equations of the porous thermoelastic solid are solved using normal mode analysis with an eigenvalue approach. In order to illustrate the analytical developments, the numerical solution is carried out, and the effect of local parameter and temperature-dependent properties on the physical fields are presented graphically.

Development of Efficient Seismic Analysis Model using 2D T-Shape Rigid-body for Wall-Frame Structures with a Central Core (이차원 T형강체를 이용한 중심코어를 가진 전단벽-골조 구조물의 효율적인 지진해석모델 개발)

  • Park, Yong-Koo;Lee, Dong-Guen;Kim, Hyun-Su
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.26 no.1
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    • pp.9-17
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    • 2013
  • In this study, an efficient analytical model for the dynamic analysis of tall buildings with a shear wall-frame structural system has been proposed. A shear wall-frame structural system usually consists of a core wall showing flexural behavior and a frame presenting shear behavior. Therefore, the deformed shape of the shear wall-frame structural system is shown by the combination of flexural mode and shear mode. These characteristics should be considered when an efficient analytical model is developed. To this end, the effect of shear wall and frame on the dynamic behavior of a tall building with a dual system has been separately investigated. In this study, the structural characteristics of a separated individual shear wall model and the frame model without shear wall has been evaluated. In order to consider the effect of the shear wall in the frame model without shear wall, a rigid body was used instead of the shear wall. Each equivalent model for the separated shear wall part and frame part has been independently developed and two equivalent models were then combined to create an efficient analytical model for tall buildings with a shear wall-frame structural system. In order to verify the efficiency and accuracy of the proposed method, time history analyses of tall buildings with a shear wall-frame system were performed. Based on analytical results, it has been confirmed that the proposed method can provide accurate results, requiring significantly reduced computational time and memory.

Mode Localization in Multispan Beams with Massive and Stiff Couplers on Supports (지점 위에 질량과 강성이 큰 연결기를 갖는 다경간 보의 모드편재)

  • Dong-Ok Kim;Sun-Kyu Park;In-Won Lee
    • Journal of KSNVE
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    • v.8 no.6
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    • pp.1166-1171
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    • 1998
  • The influences of the coupler consisting of stiffness and mass between neighboring two spans on mode localization are studied theoretically, and the results are confirmed by numerical examples. The mass of the coupler makes a structure sensitive to mode localization especially in higher modes while the stiffness does in all modes. A new type of delocalization phenomenon is observed for the first time in some modes for which mode localization does not occur or is very weak although structural disturbances are severe. A spring-mass system consisting of two substructures and a coupler connecting them is considered in the part of analytical study. As example structures for numerical analysis. simply supported continuous two-span beams with a coupler having a rotational stiffness and a mass moment of inertia on the mid support are considered.

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