• Title/Summary/Keyword: Scale-free

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Nonlocal geometrically nonlinear dynamic analysis of nanobeam using a meshless method

  • Ghadiri Rad, Mohammad Hossein;Shahabian, Farzad;Hosseini, Seyed Mahmoud
    • Steel and Composite Structures
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    • v.32 no.3
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    • pp.293-304
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    • 2019
  • In the present paper, the element free Galerkin (EFG) method is developed for geometrically nonlinear analysis of deep beams considering small scale effect. To interpret the behavior of structure at the nano scale, the higher-order gradient elasticity nonlocal theory is taken into account. The radial point interpolation method with high order of continuity is used to construct the shape functions. The nonlinear equation of motion is derived using the principle of the minimization of total potential energy based on total Lagrangian approach. The Newmark method with the small time steps is used to solve the time dependent equations. At each time step, the iterative Newton-Raphson technique is applied to minimize the residential forces caused by the nonlinearity of the equations. The effects of nonlocal parameter and aspect ratio on stiffness and dynamic parameters are discussed by numerical examples. This paper furnishes a ground to develop the EFG method for large deformation analysis of structures considering small scale effects.

Effects of Combustor-Level High Inlet Turbulence on the Endwall Flow and Heat/Mass Transfer of a High-Turning Turbine Rotor Cascade

  • Lee, Sang-Woo;Jun, Sang-Bae;Park, Byung-Kyu;Lee, Joon-Sik
    • Journal of Mechanical Science and Technology
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    • v.18 no.8
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    • pp.1435-1450
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    • 2004
  • Experimental data are presented which describe the effects of a combustor-level high free-stream turbulence on the near-wall flow structure and heat/mass transfer on the endwall of a linear high-turning turbine rotor cascade. The end wall flow structure is visualized by employing the partial- and total-coverage oil-film technique, and heat/mass transfer rate is measured by the naphthalene sublimation method. A turbulence generator is designed to provide a highly-turbulent flow which has free-stream turbulence intensity and integral length scale of 14.7% and 80mm, respectively, at the cascade entrance. The surface flow visualizations show that the high free-stream turbulence has little effect on the attachment line, but alters the separation line noticeably. Under high free-stream turbulence, the incoming near-wall flow upstream of the adjacent separation lines collides more obliquely with the suction surface. A weaker lift-up force arising from this more oblique collision results in the narrower suction-side corner vortex area in the high turbulence case. The high free-stream turbulence enhances the heat/mass transfer in the central area of the turbine passage, but only a slight augmentation is found in the end wall regions adjacent to the leading and trailing edges. Therefore, the high free-stream turbulence makes the end wall heat load more uniform. It is also observed that the heat/mass transfers along the locus of the pressure-side leg of the leading-edge horseshoe vortex and along the suction-side corner are influenced most strongly by the high free-stream turbulence. In this study, the end wall surface is classified into seven different regions based on the local heat/mass transfer distribution, and the effects of the high free-stream turbulence on the local heat/mass transfer in each region are discussed in detail.

Validation of the Korean Version of Free Will and Determinism Scale (FAD-Plus) using Confirmatory Factor Analysis - The Relationship Between Belief in Free Will and Correspondence Bias - (확인적 요인분석을 통한 한국판 자유의지와 결정론 척도(FAD-Plus)의 타당화 - 자유의지에 대한 믿음과 귀인편향의 관계 -)

  • Ahn, Jaekyung;Han, Sanghoon;Choi, Yimoon
    • Korean Journal of Forensic Psychology
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    • v.12 no.1
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    • pp.35-51
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    • 2021
  • People's belief in free will is important in determining the causes and responsibilities of human behavior. Over the past decades, there has been debate about belief in free will in the fields of neuroscience, philosophy, ethics, and criminal law. The Free Will and Determinism Scale (FAD-Plus; Paulhus & Carey, 2011) is a test tool that measures the components related to the belief in an individual's free will. This study conducted a confirmatory factor analysis of 1,000 ordinary people of various age groups and socio-economic backgrounds based on previous studies that conducted an exploratory factor analysis (Study 1). The author has secured the reliability and validity of a number of measures. Furthermore, it was examined how the sub-item of the FAD-Plus scale, 'belief in free will,' was related to correspondence bias and locus of control (Study 2). As a result of analyzing a total of 83 subjects, high belief in free will had a positive correlation with punishment judgment for negative behavior and internal attribution, but there was no significant relationship in reward judgment for positive behavior. Based on the study results, it was proven that the FAD-Plus is valid for the general public as well, and the relationship between belief in free will, attribution bias, locus of control and behavior judgment was examined. The limitations of this study, policy implications, and research directions are discussed.

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Recrystallization Topology : a Scale-free Power-law Network (재결정 위상 : 척도 없는 거듭제곱 법칙 망)

  • Park, Jae-Hyun
    • Journal of KIISE:Information Networking
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    • v.37 no.3
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    • pp.167-174
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    • 2010
  • Recently the distributed topology control algorithm for constructing the Recrystallization Topology in the unstructured peer-to-peer network was proposed. In this paper, we prove that such a hierarchical topology is a scale-free power-law network. We present a model of a construction process of the distributed protocol, and analyze it based on a mean-field approximation and the continuum theory, so that we show that the constructed Recrystallization Topology is a scale-free network. In the proposed model, all nodes are born with some initial attractiveness and the system incorporates the rewiring of some links at every time step. Some old links are removed with the anti-preferential probability, and some new links are added with preferential probability. In other words, according to the distributed algorithm, each node makes connections to the more-preferential nodes having higher hit-ratio than other nodes, while it disconnects the anti-preferential nodes having lesser hit-ratio. This gives a realistic description of the local processes forming the recrystallization topology in unstructured peer-to-peer network. We calculate analytically the degree distribution. The analytic result indicates that the constructed network is a scale-free network, of which the scaling exponent is 3.

Joint Attention and Language Development in Infants from Multi-Cultural Families (다문화 가정 유아들의 함께 주의하기와 언어발달)

  • Park, Young-Shin
    • Korean Journal of Child Studies
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    • v.31 no.6
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    • pp.35-50
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    • 2010
  • Joint attention, language development, and the relationship between these two variables were compared in infants from multi-cultural and Korean families. Joint attention was observed in both the Early Social Communication Scale (ESCS) and in infant-mother free play. Language development was evaluated by means of the MacArthur-Bates Communicative Development Inventory-Korean. There were no group differences in initiating and responding to joint attention in ESCS. However, in infant-mother free play, joint attention episodes were less and shorter in duration with infants from multi-cultural families than in Korean infants. The size of both the expressive and receptive vocabulary was also smaller in infants from multi-cultural families than in Korean infants. In terms of Korean infants, mean duration of joint attention episodes in free play showed a significant positive correlation with the size of the expressive vocabulary and initiating joint attention in ESCS also showed a significant positive correlation with the size of receptive vocabulary. However, none of the measures of joint attention indicated a significant relationship with the size of either expressive or receptive vocabulary in infants from multi-cultural families.

A Methodology to Determine Resilient Modulus for Crushed Rock-Soil Mixture (암버력-토사 성토의 회복탄성계수 산정방법)

  • Park, In-Beom;Kim, Seong-Su;Jung, Young-Hoon;Mok, Young-Jin
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.09a
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    • pp.1190-1200
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    • 2010
  • A method was developed to determine resilient modulus for crushed rock-soil mixtures whose usage has been increased recently without engineering specifications. The method is based on the subtle different modulus called nonlinear dynamic modulus and was lately implemented in residual soils and engineered crushed-stones. Hereby. the same method was expanded to crushed rock-soil mixtures containing as large grain diameter as 300mm. The method utilize field direct-arival tests for the determination of maximum Young's modulus, and a large scale free-free resonant column test, which is recently developed to is capable to test as large grain diameter as 25mm, for modulus reduction curves. The prediction model of resilient modulus was evaluated for crushed rock-soil mixtures of a highway construction site at Gimcheon, Korea.

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A Study on the Ecotourism Policy Direction of Saemangeum.Gunsan Free Economic Zone (새만금.군산경제자유구역의 생태관광 방향)

  • Lim, Hyung-Baek;Choi, Hung-Kyu;Lee, Seong-Woo
    • Hwankyungkyoyuk
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    • v.22 no.4
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    • pp.53-65
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    • 2009
  • Saemangeum is the largest reclaimed land in Korea. Saemangeum is the large scale project responding to the economic demand of globalization, and a government initiated new development business with a vision of global Free Economic Zone(FEZ). Jeollabuk-province conducted a international competition to establish a global-scale, creative development plan and grow the Saemangeum as an international destination of economy, and a world-wide brand. SGFEZ has much to offer in terms of tourists attractions and breathtaking scenery. And tourism is one of the important industry in SGFEZ. Many tourist facilities will be construct in SGFEZ. Environment is the important issue in many field of study. Recent days, green growth come into the spotlight in Korea. But even as SGFEZ prepares for its future global tourists attraction, so much of the tourism policy directions remains unconsidered. The objective of this study was to suggest tourism policy direction, especially concentrated on ecology tourism policy direction of Saemangeum Gunsan Free Economic Zone(SGFEZ).

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Buckling and free vibration analysis of FG-CNTRC-micro sandwich plate

  • Kolahdouzan, Farzad;Arani, Ali Ghorbanpour;Abdollahian, Mohammad
    • Steel and Composite Structures
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    • v.26 no.3
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    • pp.273-287
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    • 2018
  • Buckling and free vibration analysis of sandwich micro plate (SMP) integrated with piezoelectric layers embedded in orthotropic Pasternak are investigated in this paper. The refined Zigzag theory (RZT) is taken into consideration to model the SMP. Four different types of functionally graded (FG) distribution through the thickness of the SMP core layer which is reinforced with single-wall carbon nanotubes (SWCNTs) are considered. The modified couple stress theory (MCST) is employed to capture the effects of small scale effects. The sandwich structure is exposed to a two dimensional magnetic field and also, piezoelectric layers are subjected to external applied voltages. In order to obtain governing equation, energy method as well as Hamilton's principle is applied. Based on an analytical solution the critical buckling loads and natural frequency are obtained. The effects of volume fraction of carbon nanotubes (CNTs), different distributions of CNTs, foundation stiffness parameters, magnetic and electric fields, small scale parameter and the thickness of piezoelectric layers on the both critical buckling loads and natural frequency of the SMP are examined. The obtained results demonstrate that the effects of volume fraction of CNTs play an important role in analyzing buckling and free vibration behavior of the SMP. Furthermore, the effects of magnetic and electric fields are remarkable on the mechanical responses of the system and cannot be neglected.

Production of Palatinose by Immobilized Cells of Erwinia rhapontici (Erwinia rhapontici 고정화에 의한 Palatinose의 생산)

  • 윤종원;오광근
    • KSBB Journal
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    • v.7 no.1
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    • pp.79-83
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    • 1992
  • The characteristics of Erwinia rhapontici cells with $\alpha$-glucosyltransferase activity immobilized in Ca-alginate beads and the performance of two different types of reactor-stirred tank reactor(STR) and packed bed reactor(PBR)-charged with these immobilized cells to produce palatinose from sucrose were investigated. The optimal pH(5.5-6.0) and temperature($30-35^{\circ}C$) showed no appreciable difference between free and immobilized cells. The apparent Km value of the immobilized cells(0.28M) was approximately two times higher than that of free cells(0.13M) at $30^{\circ}C$. The half life of the immobilized cells was found to be 380 h with STR while much greater operational stability was achieved with PBR. Continuous operation of PBR at a space velocity of $0.2h^{-1}$ for 30 days showed only 5% loss of initial activity.

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Effects of Waves and Free-Surface Boundary Conditions on the Flow A Surface-Piercing Flat Plate (수면 관통 평판주위 유동에 미치는 파의 영향 및 자유표면 경계조건에 대한 연구)

  • Choi, Jung-Eun;Stern, F.
    • Journal of the Society of Naval Architects of Korea
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    • v.34 no.1
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    • pp.41-49
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    • 1997
  • Computational results from Navier-Stokes equations are presented for the Stokes-wave/flat-plate boundary-layer and wake for small wave steepness(Ak=0.01), including exact and approximate treatments of the viscous free-surface boundary conditions. The macro-scale flow indicate that the variations of the external-flow pressure gradients cause acceleration or deceleration of the streamwise velocity component and alternating direction of the cross flow. Remarkably, the wake displays a greater response, i.e., a bias with regard to favorable as compared to adverse pressure gradients. The micro-scale flow indicates that the free-surface boundary conditions have a profound influence over the boundary layer and near/intermediate wake. Order-of-magnitude estimates are conformed to the computational results. And appreciable errors are introduced through approximations to the free-surface boundary conditions.

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