• Title/Summary/Keyword: Interaction model

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An Experimental Study on Ship-Bank Hydrodynamic Interaction Forces

  • Lee, Chun-Gi;Mun, Seong-Bae;Jeong, Yeon-Cheol;Jeong, Tae-Gwon;Lee, Dong-Seop;Gang, Il-Gwon
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2013.06a
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    • pp.15-16
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    • 2013
  • This paper is mainly concerned with the ship-bank interaction by model test. The experiments for the characteristics of hydrodynamic interaction forces and moments between vessel and bank with a mound were carried out in the seakeeping and maneuvering basin.

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A Low-Reynolds Number Second Moment Closure for Turbulent Heat Fluxes (저레이놀즈수 2차 모멘트 난류 열유속모형 개발에 관한 연구)

  • 신종근;최영돈;이건휘
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.12
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    • pp.3196-3207
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    • 1993
  • A second moment turbulent closure for the turbulent heat flux near a wall is developed by modification of model constants in pressure interaction term as the variables of the turbulent Reynolds number using the universal properties of turbulent heat flux near the wall. The present model shows that model constant for the wall reflection term in pressure interaction is most important in modelling of the near wall heat flux. Fully developed pipe flows with constant wall heat flux are tested to validate the proposed model. In most of calculation region, the predicted turbulent properties agree better with the experimetal data than the results from standard algebraic heat flux model which use the uniform model constants.

Fluid Structure Interaction Analysis of Membrane Type LNG CCS Experiencing the Sloshing Impact by Impinging Jet Model (멤브레인형 LNG 화물창의 강도평가를 위해 적용된 분사모델을 이용한 유체구조 연성해석에 관한 연구)

  • Hwang, Se Yun;Lee, Jang Hyun
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.28 no.1
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    • pp.71-78
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    • 2015
  • The reliable sloshing assessment methods for LNG CCS(cargo containment system) are important to satisfy the structural strength of the systems. Multiphase fluid flow of LNG and Gas Compressibility may have a large effect on excited pressures and structural response. Impinging jet model has been introduced to simulate the impact of the LNG sloshing and analyze structural response of LNG CCS as a practical FSI(fluid structure interaction) method. The practical method based on fluid structure interaction analysis is employed in order to evaluate the structural strength in actual scale for Mark III CCS. The numerical model is based on an Euler model that employs the CVFEM(control volume based finite element method). It includes the particle motion of gas to simulate not only the interphase interaction between LNG liquid and gas and the impact load on the LNG insulation box. The analysis results by proposed method are evaluated and discussed for an effectiveness of FSI analysis method.

Multifactor Dimensionality Reduction (MDR) Analysis to Detect Single Nucleotide Polymorphisms Associated with a Carcass Trait in a Hanwoo Population

  • Lee, Jea-Young;Kwon, Jae-Chul;Kim, Jong-Joo
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.6
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    • pp.784-788
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    • 2008
  • Studies to detect genes responsible for economic traits in farm animals have been performed using parametric linear models. A non-parametric, model-free approach using the 'expanded multifactor-dimensionality reduction (MDR) method' considering high dimensionalities of interaction effects between multiple single nucleotide polymorphisms (SNPs), was applied to identify interaction effects of SNPs responsible for carcass traits in a Hanwoo beef cattle population. Data were obtained from the Hanwoo Improvement Center, National Agricultural Cooperation Federation, Korea, and comprised 299 steers from 16 paternal half-sib proven sires that were delivered in Namwon or Daegwanryong livestock testing stations between spring of 2002 and fall of 2003. For each steer at approximately 722 days of age, the Longssimus dorsi muscle area (LMA) was measured after slaughter. Three functional SNPs (19_1, 18_4, 28_2) near the microsatellite marker ILSTS035 on BTA6, around which the QTL for meat quality were previously detected, were assessed. Application of the expanded MDR method revealed the best model with an interaction effect between the SNPs 19_1 and 28_2, while only one main effect of SNP19_1 was statistically significant for LMA (p<0.01) under a general linear mixed model. Our results suggest that the expanded MDR method better identifies interaction effects between multiple genes that are related to polygenic traits, and that the method is an alternative to the current model choices to find associations of multiple functional SNPs and/or their interaction effects with economic traits in livestock populations.

Functions and Driving Mechanisms for Face Robot Buddy (얼굴로봇 Buddy의 기능 및 구동 메커니즘)

  • Oh, Kyung-Geune;Jang, Myong-Soo;Kim, Seung-Jong;Park, Shin-Suk
    • The Journal of Korea Robotics Society
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    • v.3 no.4
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    • pp.270-277
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    • 2008
  • The development of a face robot basically targets very natural human-robot interaction (HRI), especially emotional interaction. So does a face robot introduced in this paper, named Buddy. Since Buddy was developed for a mobile service robot, it doesn't have a living-being like face such as human's or animal's, but a typically robot-like face with hard skin, which maybe suitable for mass production. Besides, its structure and mechanism should be simple and its production cost also should be low enough. This paper introduces the mechanisms and functions of mobile face robot named Buddy which can take on natural and precise facial expressions and make dynamic gestures driven by one laptop PC. Buddy also can perform lip-sync, eye-contact, face-tracking for lifelike interaction. By adopting a customized emotional reaction decision model, Buddy can create own personality, emotion and motive using various sensor data input. Based on this model, Buddy can interact probably with users and perform real-time learning using personality factors. The interaction performance of Buddy is successfully demonstrated by experiments and simulations.

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A Study on the Behavior of High-rise Buildings Considering Soil-Structure Interaction (지반-구조물 상호작용을 고려한 고층 구조물의 거동에 관한 연구)

  • Kim, Se-Hyun;Park, Sung-Soo
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.9 no.4
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    • pp.243-251
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    • 2005
  • In the seismic design the pile foundation system of the buildings generally have been modeled to have a fixed end for its convenience and conservativeness. But it is necessary to consider the soil-structure interaction for more reliable design. In this study, the framed tube building and brace tube building with pile foundation system under earthquake were analyzed considering soil-structural interaction by 3 pile foundation modeling methods; fixed-end model, 6 springs model and p-y springs model. And 2 soil conditions were used in analysis. For each cases, displacements, drifts, maximum stress, periods and 1st mode mass participation ratios were compared.

정익과 동익의 상호작용에 의한 비정상 천이 경계층 유동의 수치해석에 관한 연구 1

  • Kang, Dong-Jin;Lakshminarayana, Budugur
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.22 no.6
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    • pp.757-770
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    • 1998
  • A Navier-Stokes code with a low Reynolds number k-.epsilon. turbulence model was tested to investigate its predictability for the unsteady transitional boundary layer flow due to rotor-stator interaction. A preliminary calculation with three different numbers of time steps 300, 600, and 1000 for a rotor wake passing period was carried out to see the effects of time steps on the unsteady flow and pressure fields due to rotor-stator interaction. Numerical solutions showed that unsteady pressure was much more sensitive to the number of time steps and over 600 time steps should be used to get a numerical solution independent of the number of time steps for a rotor wake passing period. The original low Reynolds number k-.epsilon. turbulence model showed very poor prediction of the unsteady transitional boundary layer flow due to rotor-stator interaction. This was due to the excessive production of turbulent kinetic energy near the leading edge. A modification suggested by Launder was incorporated and the modified model captured well the wake induced transitional strip. Present solutions also showed improved prediction over previous Euler/boundary layer solution in terms of the onset of unsteady transition and its extent.

A Study on the Significance of Spatial Interaction Model from the Urban Competitive Point of View (입지 경쟁력과 공간상호작용 모형의 유의성 검정)

  • Kim, Dong-Yoon
    • Journal of The Korean Digital Architecture Interior Association
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    • v.12 no.1
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    • pp.71-79
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    • 2012
  • This study aims at finding relationships between the competitiveness of cities and the size or distance of them, based on some premises; (1) the competitiveness can be measured on the interval-ratio level, that is, factor scores, (2) a hypothesis that the spatial interaction model is valid for the relationships can be generally accepted. Based on the general recognition a research hypothesis that the more is the population or the nearer is the distance from a central city the higher is the competitiveness score is constructed. According to the premises 5-factor scores and composite score are calculated by means of regression method, and the scores are regressed on cities' populations and distances from Seoul city. Using bootstrapping method for the tests of significance is effective due to small sample of 21 cities. Results of the analyses show that most aspects of the hypothesis should be rejected or adjusted. Scores on Health-welfare factor, public service factor, and commercial vitality factor have no relation to the cities' sizes or distances. But the results also find the facts that the strong (negative) relationships exist between (1) educational base factor score and population, (2) density factor score and distance. Although this study improves systematic and analytic understanding of spatial interaction patterns, the understanding should be invalid for the general context because it has used the data on 21 cities in the capital region at the time of 2009.

SIMULATION OF FLUID-STRUCTURE INTERACTION OF A TOWED BODY USING AN ASYMMETRIC TENSION MODEL (비대칭 장력 모델을 이용한 예인 물체의 유체-구조 상호작용 모사)

  • Shin, Sang-Mook
    • Journal of computational fluids engineering
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    • v.16 no.1
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    • pp.7-13
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    • 2011
  • The fluid-structure interaction of a towed body is simulated using a developed code, which is based on the flux-difference splitting scheme on the hybrid Cartesian/immersed boundary method. To improve the stability in the coupling between the fluid and structure domains, a scheme is used, in which the effects of structure deformation are treated implicitly. The developed code is validated for the fluid-structure interaction problem through comparisons with other results on the vortex-induced vibration of elastically mounted cylinders. To simulate behavior of a towed body, an asymmetric tension modelling for a towing cable is suggested. In the suggested model, the tension is proportional to the elongation of the cable, but the cable has no effect on the body motion whenever the distance between the endpoints of the cable is smaller than the original length of the cable. The fluid-structure interactions of a towed body are simulated on the basis of different parameters of the towing cables. It is observed that the suggested tension model predicts the snapping for a shorter towing cable, which is in accordance with the reported results.

Dynamic Interaction Analysis of Interconnected Wind Power Generator using Computer Simulation and Real-Size Hardware Simulator (컴퓨터 시뮬레이션과 실규모 하드웨어시뮬레이터를 이용한 계통연계 풍력발전의 응동특성 분석)

  • Yun, Dong-Jin;Han, Byung-Moon;Choy, Young-Do;Jeon, Young-Soo;Jeong, Byoung-Chang;Chung, Yong-Ho
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.1047_1048
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    • 2009
  • This paper describes comparative analysis results about the dynamic interaction of interconnected wind power system using the actual-size hardware simulator and the simulation model with PSCAD/EMTDC. The hardware simulator, which is composed of 2.0MVA induction motor with drive system and 1.5MW doubly-fed induction generator, was built and tested in Go-Chang Test Site of KEPCO for analyzing the dynamic interaction with the interconnected distribution system. The operation of hardware simulator was verified through comparative analysis between experimental results and simulation results obtained by simulation model with PSCAD/EMTDC. The developed hardware simulator and simulation model could be effectively used for analyzing the dynamic interaction, which has various phenomena depending on the wind variation and the network state of interconnected power system.

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