• Title/Summary/Keyword: non-classical

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A debate between Eternalism and Temporalism focused on Anaphoric 'that' argument (대용어적 '그것' 논증을 둘러싼 영원주의와 일시주의 사이의 논쟁에 대하여)

  • Choi, Dongho
    • Korean Journal of Logic
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    • v.19 no.3
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    • pp.401-435
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    • 2016
  • Can a proposition that a sentence like "It is raining" represents be sometimes itself? or is it always ? This is known as the debate between Eternalism and Temporalism and belongs to the sub-category of the wider debate between Classical Propositionalism and Non-classical Propositionalism. Regarding this matter, Cappelen and Hawthorne(2009), supporting Eternalism[Classical Propositionalism], raise interesting objection to anaphoric 'that' argument that is one of the famous arguments supporting Temporalism. In this paper, I try to show how difficult it is to advocate Classical Propositionalism by refuting what Cappelen and Hawthorne claim.

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Influence of impulsive line source and non-homogeneity on the propagation of SH-wave in an isotropic medium

  • Kakar, Rajneesh
    • Interaction and multiscale mechanics
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    • v.6 no.3
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    • pp.287-300
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    • 2013
  • In this paper, the effect of impulsive line on the propagation of shear waves in non-homogeneous elastic layer is investigated. The rigidity and density in the intermediate layer is assumed to vary quadratic as functions of depth. The dispersion equation is obtained by using the Fourier transform and Green's function technique. The study ends with the mathematical calculations for transmitted wave in the layer. These equations are in complete agreement with the classical results when the non-homogeneity parameters are neglected. Various curves are plotted to show the effects of non-homogeneities on shear waves in the intermediate layer.

Non-associative fuzzy-relevance logics: strong t-associative monoidal uninorm logics

  • Yang, Eun-Suk
    • Korean Journal of Logic
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    • v.12 no.1
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    • pp.89-110
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    • 2009
  • This paper investigates generalizations of weakening-free uninorm logics not assuming associativity of intensional conjunction (so called fusion) &, as non-associative fuzzy-relevance logics. First, the strong t-associative monoidal uninorm logic StAMUL and its schematic extensions are introduced as non-associative propositional fuzzy-relevance logics. (Non-associativity here means that, differently from classical logic, & is no longer associative.) Then the algebraic structures corresponding to the systems are defined, and algebraic completeness results for them are provided. Next, predicate calculi corresponding to the propositional systems introduced here are considered.

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Stability of perforated nanobeams incorporating surface energy effects

  • Almitani, Khalid H.;Abdelrahman, Alaa A.;Eltaher, Mohamed A.
    • Steel and Composite Structures
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    • v.35 no.4
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    • pp.555-566
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    • 2020
  • This paper aims to present an analytical methodology to investigate influences of nanoscale and surface energy on buckling stability behavior of perforated nanobeam structural element, for the first time. The surface energy effect is exploited to consider the free energy on the surface of nanobeam by using Gurtin-Murdoch surface elasticity theory. Thin and thick beams are considered by using both classical beam of Euler and first order shear deformation of Timoshenko theories, respectively. Equivalent geometrical constant of regularly squared perforated beam are presented in simplified form. Problem formulation of nanostructure beam including surface energies is derived in detail. Explicit analytical solution for nanoscale beams are developed for both beam theories to evaluate the surface stress effects and size-dependent nanoscale on the critical buckling loads. The closed form solution is confirmed and proven by comparing the obtained results with previous works. Parametric studies are achieved to demonstrate impacts of beam filling ratio, the number of hole rows, surface material characteristics, beam slenderness ratio, boundary conditions as well as loading conditions on the non-classical buckling of perforated nanobeams in incidence of surface effects. It is found that, the surface residual stress has more significant effect on the critical buckling loads with the corresponding effect of the surface elasticity. The proposed model can be used as benchmarks in designing, analysis and manufacturing of perforated nanobeams.

Nonlocal vibration analysis of FG nano beams with different boundary conditions

  • Ehyaei, Javad;Ebrahimi, Farzad;Salari, Erfan
    • Advances in nano research
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    • v.4 no.2
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    • pp.85-111
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    • 2016
  • In this paper, the classical and non-classical boundary conditions effect on free vibration characteristics of functionally graded (FG) size-dependent nanobeams are investigated by presenting a semi analytical differential transform method (DTM) for the first time. Three kinds of mathematical models, namely; power law (P-FGM), sigmoid (S-FGM) and Mori-Tanaka (MT-FGM) distribution are considered to describe the material properties in the thickness direction. The nonlocal Eringen theory takes into account the effect of small size, which enables the present model to become effective in the analysis and design of nanosensors and nanoactuators. Governing equations are derived through Hamilton's principle and they are solved applying semi analytical differential transform method. The good agreement between the results of this article and those available in literature validated the presented approach. The detailed mathematical derivations are presented and numerical investigations are performed while the emphasis is placed on investigating the effect of the several parameters such as small scale effects, spring constant factors, various material compositions and mode number on the normalized natural frequencies of the FG nanobeams in detail. It is explicitly shown that the vibration of FG nanobeams is significantly influenced by these effects. Numerical results are presented to serve as benchmarks for future analyses of FG nanobeams.

Dermatomyositis sine dermatitis, a rare phenotype of idiopathic inflammatory myopathy

  • Park, Jin-Sung;Park, Ji-Young
    • Journal of Yeungnam Medical Science
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    • v.34 no.1
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    • pp.137-139
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    • 2017
  • Dermatomyositis (DM) is characterized by progressive proximal limb weakness and typical skin manifestations. The histological findings that show perifascicular atrophy and deposition of membrane attack complex are pathognomic features of DM. Dermatomyositis is categorized into classical DM and non-classical DM, which includes amyopathic DM and DM sine dermatitis. DM sine dermatitis is seldom described because of its rarity, making the diagnosis more challenging. We report a case of DM sine dermatitis, a rare phenotype of DM.

Comparative study on dynamic analyses of non-classically damped linear systems

  • Greco, Annalisa;Santini, Adolfo
    • Structural Engineering and Mechanics
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    • v.14 no.6
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    • pp.679-698
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    • 2002
  • In this paper some techniques for the dynamic analysis of non-classically damped linear systems are reviewed and compared. All these methods are based on a transformation of the governing equations using a basis of complex or real vectors. Complex and real vector bases are presented and compared. The complex vector basis is represented by the eigenvectors of the complex eigenproblem obtained considering the non-classical damping matrix of the system. The real vector basis is a set of Ritz vectors derived either as the undamped normal modes of vibration of the system, or by the load dependent vector algorithm (Lanczos vectors). In this latter case the vector basis includes the static correction concept. The rate of convergence of these bases, with reference to a parametric structural system subjected to a fixed spatial distribution of forces, is evaluated. To this aim two error norms are considered, the first based on the spatial distribution of the load and the second on the shear force at the base due to impulsive loading. It is shown that both error norms point out that the rate of convergence is strongly influenced by the spatial distribution of the applied forces.

STABILITY ANALYSIS FOR PREDATOR-PREY SYSTEMS

  • Shim, Seong-A
    • The Pure and Applied Mathematics
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    • v.17 no.3
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    • pp.211-229
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    • 2010
  • Various types of predator-prey systems are studied in terms of the stabilities of their steady-states. Necessary conditions for the existences of non-negative constant steady-states for those systems are obtained. The linearized stabilities of the non-negative constant steady-states for the predator-prey system with monotone response functions are analyzed. The predator-prey system with non-monotone response functions are also investigated for the linearized stabilities of the positive constant steady-states.

Free Vibration of Beam-Columns on Non-Homogeneous Foundation (비균질 탄성지반 위에 놓인 보-기둥의 자유진동)

  • 이병구;오상진;이태은
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 1999.10c
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    • pp.206-211
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    • 1999
  • The purpose of this study is to investigate the natural frequencies and mode shapes of beam-columns on the non-homogeneous foundaion. The beam model is based on the classical Bernoulli-Euler beam theory. The linear foundation modulus is chosen as the non-homogeneous foundation in this study . The differentidal equation goeverning free vibrations of such beam-columns subjected to axial load is derived and solved numerically for calculting the natural frquencies and mode shapes. In numerical fivekinds of end constraint are considered, and the lowest four natural frquencies and corresponding mode shape are obtained as the non-dimensional forms.

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Modeling and Vibration Feedback Control of Rotating Tapered Composite Thin-Walled Blade

  • Shim, Jae-Kyung;Sungsoo Na
    • Journal of Mechanical Science and Technology
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    • v.17 no.3
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    • pp.380-390
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    • 2003
  • This paper addresses the problem of the modeling and vibration control of tapered rotating blade modeled as thin-walled beams and incorporating damping capabilities. The blade model incorporates non-classical features such as anisotropy, transverse shear, secondary warping and includes the centrifugal and Coriolis force fields. For the rotating blade system, a thorough validation and assessment. of a number of non-classical features including the taper characteristics is accomplished. The damping capabilities are provided by a system of piezoactuators bonded or embedded into the structure and spread over the entire span of the beam. Based on the converse piezoelectric effect, the piezoactuators produce a localized strain field in response to a voltage and consequently, a change of the dynamic response characteristics is induced. A velocity feedback control law relating the piezoelectrically induced transversal bending moment at the beam tip with the appropriately selected kinematical response quantity is used and thebeneficial effects upon the closed-loop dynamic characteristics of the blade are highlighted.