• Title/Summary/Keyword: IS interaction

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Development of a Computational Method of 3-D Unsteady Incompressible Flow in Turbomachinery (터보기계내의 3차원 비정상 비압축성 유동계산방법의 개발)

  • Kim, Bbong-Kyun;Park, Jae-In;Joo, Won-Gu;Cho, Kang-Rae
    • The KSFM Journal of Fluid Machinery
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    • v.2 no.2 s.3
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    • pp.57-63
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    • 1999
  • The flow through multistage turbomachinery is affected by the interaction between a rotor and a stator. The interaction is due to the inviscid potential effect and viscous effect between closely spaced rotor and stator airfoils. Three-dimensional, unsteady, incompressible Navier-Stokes equations with a standard $k-{\epsilon}$ model are solved using a non-staggered grid system. This method is applied to the flow through a multistage compressor measured by Stauter et al. The results have shown strong interaction between the rotating and stationary flow field. The decay of rotor wake and the pressure profiles agree very well with experimental data. The wake produced by rotor causes unsteady pressure on the surface of a stator. The rotor/stator interaction produces the unsteady pressure force on the rotor and stator blades.

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Inelastic seismic analysis of RC bridge piers including flexure-shear-axial interaction

  • Lee, Do Hyung;Elnashai, Amr S.
    • Structural Engineering and Mechanics
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    • v.13 no.3
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    • pp.241-260
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    • 2002
  • The effect of shear coupled with axial force variation on the inelastic seismic behaviour of reinforced concrete bridge piers is investigated in this paper. For this purpose, a hysteretic axial-shear interaction model was developed and implemented in a nonlinear finite element analysis program. Thus, flexure-shear-axial interaction is simulated under variable amplitude reversed actions. Comparative studies for shear-dominated reinforced concrete columns indicated that a conventional FE model based on flexure-axial interaction only gave wholly inadequate results and was therefore incapable of predicting the behaviour of such members. Analysis of a reinforced concrete bridge damaged during the Northridge (California 1994) earthquake demonstrated the importance of shear modelling. The contribution of shear deformation to total displacement was considerable, leading to increased ductility demand. Moreover, the effect of shear with axial force variation can significantly affect strength, stiffness and energy dissipation capacity of reinforced concrete members. It is concluded that flexure-shear-axial interaction should be taken into account in assessing the behaviour of reinforced concrete bridge columns, especially in the presence of high vertical ground motion.

Seismic Analysis of Rack Structure with Fluid-Structure Interaction (유체와 구조물의 연성을 고려한 rack 구조물의 내진해석)

  • Kim, S.J.;Lee, Y.S.;Ryu, C.H.;Yang, K.H.;Jung, S.H.
    • Proceedings of the KSME Conference
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    • 2001.11a
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    • pp.465-470
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    • 2001
  • In this study, the seismic analysis of rack structure with fluid-structure interaction is performed through use of the Finite Element Method(FEM) code ANSYS. Fluid-structure interaction can specify in terms of an hydrodynamic effect which is defined as the added mass per unit length divided by the area of the cross section. Using the Floor Response Spectrum(FRS) obtained through the time-history analysis, modal analysis and seismic analysis under Operating Basis Earthquake(OBE) and Safe Shutdown Earthquake(SSE) condition is carried out. The fluid-structure interaction effects on the rack structure are investigated.

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Vertical Vibration Analysis of Single Pile-Soil Interaction System Considering the Interface Spring (접합면 스프링요소를 고려한 단말뚝-지반 상호작용계의 수직진동해석)

  • 김민규;김문겸;이종세
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2002.09a
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    • pp.106-113
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    • 2002
  • In this study, a numerical analysis method for soil-pile interaction in frequency domain problem is presented. The total soil-pile interaction system is divided into two parts so called near field and far field. In the near field, beam elements are used for a pile and plain strain finite elements for soil. In the far field, dynamic fundamental solution for multi-layered half planes based on boundary element formulation is adopted for soil. These two fields are coupled using FE-BE coupling technique In order to verify the proposed soil-pile interaction analysis, the dynamic responses of pile on multi-layered half planes are simulated and the results are compared with the experimental results. Also, the dynamic response analyses of interface spring elements are performed. As a result, less spring stiffness makes the natural frequency decrease and the resonant amplitude increase.

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Natural Frequency Analysis of Sliders and Head/Disk Interaction Detection by Acoustic Emission

  • Hwang, Pyung;Pan, Galina;Khan, Polina
    • KSTLE International Journal
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    • v.5 no.1
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    • pp.28-31
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    • 2004
  • The object of the present work is the natural frequency analysis of subambient pressure tri-pad and pico sliders. Head/disk interaction during start/stop and constant speed were detected by using the acoustic emission (AE) test system. The frequency spectrum analysis is performed using the AE signal obtained during the head/disk interaction. The FFT (Fast Fourier Transform) analysis of the AE signals is used to understand the interaction between the AE signal and the state of contact. Natural frequency analysis was performed using the Ansys program. The results indicate acceptable accordance of finite element calculation results with the experimental results.

Toward an Accurate Self-interaction Binding Energy of Magic Cluster TiAu_4

  • Han, Young-Kyu;Kim, Jong-Chan;Jung, Jae-Hoon;Yu, Ung-Sik
    • Bulletin of the Korean Chemical Society
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    • v.29 no.2
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    • pp.305-308
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    • 2008
  • We performed coupled-cluster calculations to determine the intermolecular interaction energy between two TiAu4 clusters. Our ab initio calculations predict that the binding energy is 2.89 eV, which is somewhat larger than the known binding energy of 2.0 eV for TiH4-TiH4. The intermolecular binding energy is relatively high, despite TiAu4 having all the attributes of a magic cluster. The favorable orbital interaction between occupied Au(6s) and unoccupied Ti(3d) orbitals leads to the strong dimeric interaction for TiAu4-TiAu4.

Electrostatic Interaction Between Oligopeptides and Phosphate Residues by Determination of Absolute Raman Intensities

  • Kye-Taek Lim
    • Bulletin of the Korean Chemical Society
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    • v.12 no.3
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    • pp.286-289
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    • 1991
  • The changed isotropic absolute Raman intensities of the phosphate residue in the complexes of positive charge oligopeptides, lys-lys, arg-arg, lys-aromat-lys, negative charge diethyl phosphoric acid (DEP) and polyriboadenylic acid{poly(rA)} were reported and discussed. Our measurements showed that the absolute intensities of phosphate stretch vibration in complexes were different according to the reaction partners. Due to the partial electrical charge and molecular structure of oligopeptides for the complex formation lysine can interact more strongly than arginine when the reaction partners have short chain and no steric hindrance. Owing to these reasons the intensity of phosphate stretching vibration is very sensitive according to the circumstance of reaction. From our results we could suggest that we can discriminate any one of the the lysine and arginine in the complicated biological molecule during interaction between nucleotides and proteins. The activity of reaction of two basical oligopeptides is not quite similar for complex formation in aqueous solution. The activity of dipeptides depends upon the structure of molecule and environment for complex formation. Aromatic ring contributes to electrostatic interaction in complexes. The amount of the absolute intensity for pure stacking interaction is smaller than electrostatic interaction in macromolecular complexes.

Protein-Protein Interaction Prediction using Interaction Significance Matrix (상호작용 중요도 행렬을 이용한 단백질-단백질 상호작용 예측)

  • Jang, Woo-Hyuk;Jung, Suk-Hoon;Jung, Hwie-Sung;Hyun, Bo-Ra;Han, Dong-Soo
    • Journal of KIISE:Software and Applications
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    • v.36 no.10
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    • pp.851-860
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    • 2009
  • Recently, among the computational methods of protein-protein interaction prediction, vast amounts of domain based methods originated from domain-domain relation consideration have been developed. However, it is true that multi domains collaboration is avowedly ignored because of computational complexity. In this paper, we implemented a protein interaction prediction system based the Interaction Significance matrix, which quantified an influence of domain combination pair on a protein interaction. Unlike conventional domain combination methods, IS matrix contains weighted domain combinations and domain combination pair power, which mean possibilities of domain collaboration and being the main body on a protein interaction. About 63% of sensitivity and 94% of specificity were measured when we use interaction data from DIP, IntAct and Pfam-A as a domain database. In addition, prediction accuracy gradually increased by growth of learning set size, The prediction software and learning data are currently available on the web site.

A Study on the Interaction Smart Space Model in the Untact Environment (언택트 환경에서의 스마트 인터랙션 공간 모델 연구)

  • Yun, Chang Ok;Lee, Byung Chun;Kwon, Kyung Su
    • Journal of the Korea Convergence Society
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    • v.12 no.1
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    • pp.89-97
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    • 2021
  • Recently, as the importance of forced indoor living has increased in the untact era, the connection and relationship between space environments is increasing. That is, the smart interaction environment for providing services in various spaces collects and processes a number of surrounding environment information through various sensors to provide desired information according to the required place and time. In this environment, a new type of interaction paradigm is needed for the user to select and focus on environmental information. In this paper, we provide guidelines based on models and patterns for designing various interactions around space. Through interaction model-based technology, we provide guidelines for space-oriented interaction design. We propose an ideal interaction environment through guideline-based patterns and templates. Finally, by providing a space-oriented interaction environment suitable for smart interaction, users can freely obtain desired information.

Intelligent hybrid controlled structures with soil-structure interaction

  • Zhang, X.Z.;Cheng, F.Y.;Lou, M.L.
    • Structural Engineering and Mechanics
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    • v.17 no.3_4
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    • pp.573-591
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    • 2004
  • A hybrid control system is presented for seismic-resistant building structures with and without soil-structure interaction (SSI). The hybrid control is a damper-actuator-bracing control system composed of passive and active controllers. An intelligent algorithm is developed for the hybrid system, in which the passive damper is designed for minor and moderate earthquakes and the active control is designed to activate when the structural response is greater than a given threshold quantity. Thus, the external energy for active controller can be optimally utilized. In the control of a multistory building, the controller placement is determined by evaluating the optimal location index (OLI) calculated from six earthquake sources. In the study, the soil-structure interaction is considered both in frequency domain and time domain analyses. It is found that the interaction can significantly affect the control effectiveness. In the hybrid control algorithm with intelligent strategy, the working stages of passive and active controllers can be different for a building with and without considering SSI. Thus SSI is essential to be included in predicting the response history of a controlled structure.