• Title/Summary/Keyword: consistent

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A New Model to Predict Effective Elastic Constants of Composites with Spherical Fillers

  • Kim, Jung-Yun;Lee, Jae-Kon
    • Journal of Mechanical Science and Technology
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    • v.20 no.11
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    • pp.1891-1897
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    • 2006
  • In this study, a new model to predict the effective elastic constants of composites with spherical fillers is proposed. The original Eshelby model is extended to a finite filler volume fraction without using Mori-Tanaka's mean field approach. When single filler is embedded in the matrix, the effective elastic constants of the composite are computed. The composite is in turn considered as a new matrix, where new single filler is again embedded in the matrix. The predicted results by the present model with a series of embedding procedures are compared with those by Mori-Tanaka, self-consistent, and generalized self-consistent models. It is revealed through parametric studies such as stiffness ratio of the filler to the matrix and filler volume fraction that the present model gives more accurate predictions than Mori-Tanaka model without using the complicated numerical scheme used in self-consistent and generalized self-consistent models.

Strong Consistent Estimator for the Expectation of Fuzzy Stochastic Model

  • Kim, Yun-Kyong
    • International Journal of Reliability and Applications
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    • v.1 no.2
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    • pp.123-131
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    • 2000
  • This paper concerns with the consistent estimator for the fuzzy expectation of a random variable taking values in the space F($R^p$) of upper semicontinuous convex fuzzy subsets of $R^p$ with compact support. We introduce the concept of a fuzzy sample mean and show that the fuzzy sample mean is a strong consistent estimator for the fuzzy expectation. Some examples are given to illustrate the main result.

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SOFT DECISION CONTEXTS BASED ON SOFT CONTEXTS

  • Won Keun, Min
    • Honam Mathematical Journal
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    • v.44 no.4
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    • pp.628-635
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    • 2022
  • For another study of soft context and soft concept closely related to formal context and formal concept, in this paper, we propose the notions of conditional concepts, decision concepts and soft decision context based on soft contexts. Subsequently, the notions of consistent soft decision context and consistent set are introduced, and some properties for consistent set of soft decision contexts are investigated.

A Consistent Test for Linearity for a Class of General First order Nonlinear Time Series

  • Hwang, Sun Y.
    • Journal of the Korean Statistical Society
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    • v.27 no.4
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    • pp.451-458
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    • 1998
  • Problem of testing linearity among general class of first order nonlinear time series models is discussed. The null hypotheses of linearity is identified via conditional expectations. A consistent test is then suggested and relevant limiting results are derived. It is worth indicating that any specific alternatives are not specified.

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Pattern recognition as a consistent labeling problem

  • Ishikawa, Seiji;Kurokawa, Kiyoshi;Kojima, Ken-Ichi;Kato, Kiyoshi
    • 제어로봇시스템학회:학술대회논문집
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    • 1989.10a
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    • pp.999-1004
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    • 1989
  • This paper discusses a new method of recognizing patterns employing consistent labeling. A consistent labeling problem is a generalized expression of constraint satisfaction problems. When a pattern is recognized by pattern matching, the matching between a reference pattern and an acquired pattern resolves itself into finding correspondence between the pixels on the former and those on the latter. This can be expressed as a consistent labeling problem. Pattern association, a variation of pattern recognition, is also described employing consistent labeling. The proposed technique is supported by experimental results, yet further studies need to be done before its practical use.

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Consistent couple-stress theory for free vibration analysis of Euler-Bernoulli nano-beams made of arbitrary bi-directional functionally graded materials

  • Nejad, Mohammad Zamani;Hadi, Amin;Farajpour, Ali
    • Structural Engineering and Mechanics
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    • v.63 no.2
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    • pp.161-169
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    • 2017
  • In this paper, using consistent couple stress theory and Hamilton's principle, the free vibration analysis of Euler-Bernoulli nano-beams made of bi-directional functionally graded materials (BDFGMs) with small scale effects are investigated. To the best of the researchers' knowledge, in the literature, there is no study carried out into consistent couple-stress theory for free vibration analysis of BDFGM nanostructures with arbitrary functions. In addition, in order to obtain small scale effects, the consistent couple-stress theory is also applied. These models can degenerate into the classical models if the material length scale parameter is taken to be zero. In this theory, the couple-tensor is skew-symmetric by adopting the skew-symmetric part of the rotation gradients as the curvature tensor. The material properties except Poisson's ratio are assumed to be graded in both axial and thickness directions, which it can vary according to an arbitrary function. The governing equations are obtained using the concept of Hamilton principle. Generalized differential quadrature method (GDQM) is used to solve the governing equations for various boundary conditions to obtain the natural frequencies of BDFG nano-beam. At the end, some numerical results are presented to study the effects of material length scale parameter, and inhomogeneity constant on natural frequency.

The ability of panoramic radiography in assessing maxillary sinus inflammatory diseases

  • Nah, Kyung-Soo
    • Imaging Science in Dentistry
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    • v.38 no.4
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    • pp.209-213
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    • 2008
  • Purpose : To evaluate the relative diagnostic accuracy of panoramic radiography and Water's projection in maxillary sinus inflammatory diseases by comparing the radiodensities of the images with those of CT. Materials and Methods : Panoramic radiographs, Waters' projection, and CT images from 55 subjects (11O sinuses) were included in this retrospective study. The radiodensity of each maxillary sinus in panoramic radiography was recorded separately as upper and lower divided horizontally by hard palate. In Waters' projection, the overall sinus radiodensity was recorded. The CT images were considered as gold standard. Results : In panoramic radiography, 83 sinuses had same upper and lower radiodensity and 72 of these were consistent with those of CT, 26 sinuses had different upper and lower radiodensity and 15 of these, upper radiodensity was consistent with CT, the remaining 11, lower radiodensity was consistent with CT. One sinus had upper radiolucency with lower radiopacity and both were consistent with those of CT. Altogether 73 (66.4%) among 110 sinuses in panoramic radiography showed full agreement with CT, 26 (23.6%) showed partial agreement with CT. 9 sinuses had no lower image under the hard palate in panoramic radiography due to the smaller size of sinus. In Waters' projection, the radiodensity of 105 sinuses (95.5%) were consistent with that of CT. Conclusion : The panoramic radiography showed 90.0% of the sinus conditions fully or partially which may appear less accurate than that of Water's view (95.5%) but with more detailed information of the inferior part of sinuses. (Korean J Oral Maxillofac Radiol 2008; 38 : 209-13)

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Resolving an entangled cord by consistent labeling

  • Nogami, Yuyo;Ishikawa, Seiji;Kato, Kiyoshi
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10a
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    • pp.442-445
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    • 1996
  • This paper proposes a technique for analyzing mutual relation of an entangled cord by consistent labeling. Cords are often entangled unexpectedly and sometimes they even produce knots. The purpose of this study is to provide an algorithm to resolve such entangled cords automatically. It may as well have applications in future to recognizing the structure of tree branches, angiography, abdominal intestines, etc.

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Rate-dependent Viscoplastic-Damage Model of Concrete under Cyclic Loading (반복하중을 받는 콘크리트의 재하속도 의존 점소성-손상 모델)

  • 송하원;임현우;김인순
    • Proceedings of the Korea Concrete Institute Conference
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    • 1998.10a
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    • pp.468-473
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    • 1998
  • The objective of this paper is to develop a consistent algorithm for the finite element analysis for behavior of concrete under cyclic loading using viscoplastic-damage model. For modeling the behavior of concrete under cyclic loading, consistent algorithms of rate-dependent viscoplastic-damage are employed with a Willam-Warnke 5-parameter failure criterion which can consider the softening behavior of concrete and consistent tangent moduli are derived. Using finite element program implemented with the developed algorithms, the algorithms are verified and the behaviors of concrete under cylic loading are simulated and compared with experimental data.

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The Effect of Hydrodynamic Interaction on the Dynamics of Dilute Polymer Solution (묽은 고분자 용액의 거동에 대한 Hydrodynamic Interaction의 영향)

  • 안경현
    • The Korean Journal of Rheology
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    • v.4 no.2
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    • pp.127-137
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    • 1992
  • 묽은 고분자 용액의 유변학적 거동을 elastic dumbbell 모델을 사용하여 연구하면서 hydrodynamic interaction(H.I) 효과를 주로 살펴보았다. 먼저 consistent averaging방법을 사용하면서 Oseen tensor와 Rotne-Prager-Yama-kawa(R-P-Y) tensor를 H. I. tensor로 각 각 사용하여 그차이를 비교하였으며 oseen tensor를 사용하는 경우 tti-nger의 알고리듬과 Ahn과 Lee의 알고리듬을 비교하였다. 또 H.I. tensor를 처리하는 방법으로 consistent averaging 방법과 Gaussian approximation 방법의 차이에 대하여도 살펴보았다. Ahn과 Lee 의 알고리듬이 ttinger의 알고리듬보다 훨씬 빠른 계산시간을 보여주었으며 Gaussian approximation 방법을 사용하는 경우 consistent averaging 방법과 달리 second normal stress coefficient가 음의 값을 보이므로 더 합리적인 방법으로 생각된다.

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