• Title/Summary/Keyword: Sanders theory

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Parametric vibration analysis of single-walled carbon nanotubes based on Sanders shell theory

  • Khadimallah, Mohamed A.;Hussain, Muzamal;Taj, Muhammad;Ayed, Hamdi;Tounsi, Abdelouahed
    • Advances in nano research
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    • v.10 no.2
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    • pp.165-174
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    • 2021
  • This paper based on Sanders theory aims to investigate the vibration of SWCNTs considering the clamped-simply supported, clamped-free, clamped-clamped and simply supported-simply supported end conditions. After developing the governing equation of the objective system, the Rayleigh-Ritz technique is implemented for the purpose of obtaining the frequency equation in the eigen form. In addition, the applicability of this model for the analysis of vibration of CNTs is examined with the effect of length and ratio of height-to-radius. A detailed description of different types of SWCNTs with different indices is provided in the theoretical methodology. The effect of extended length is stimulated with increasing the radii and the model is effective because it also predicts the effect of thickness on vibration of SWCNTs. For different boundary conditions, the present results are verified with earlier literature.

A Study on the Meaning of Myth and Sign in the Matter of Cultural Modernization of Architecture - focused on the thinking of Ernst Cassirer and Charles Sanders Peirce - (건축의 문화적 현대화에 있어 신화와 기호의 의미에 관한 연구 -철학가 카시러와 기호학자 퍼스의 사유방식을 중심으로-)

  • Byun, Tae-Ho
    • Journal of architectural history
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    • v.12 no.4 s.36
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    • pp.49-62
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    • 2003
  • Vesely explains, the main source of our confusion and nihilism comes most probably from the ambiguous relationship between modem architecture, technology and aesthetics. Also, to overcome such crucial problems, many theorists recently emphasize to take part in cultural civilization and to preserve creative genes of great culture that is based on our interpretation of 'ethical and mythical nucleus of mankind,' rather than in technical modernization that constitutes a sort of subtle destruction of mytho-ethical nucleus of a society. They for architecture also strongly stress on a mythopoetic imagination and an ontological construction of building, which could make a form symbolic and mythical rather than mathematical and aesthetic representation. On this point, 'myth' becomes a vital idea for constructing and construing architectural form and space. And it is also one of the essential concepts to understand both the motive power of cultural continuation of place and the meaning of architecture. Nevertheless, its meaning and the citation of word in architectural essay are still obscure. It might be because the original concept of myth not only has been lain in the matter of philosophical contemplation. Thus, the intention of the research is focused on lightening the meaning of myth in architectural term. Especially, it is, first, concentrated on interpreting philosopher Ernst Cassirer's reflections which were written in order to emphasize the importance of 'mythical consciousness' for the world's cultural civilization. And, the second, it will continue to interpret the myth as a sign within the semiotic concept of Charles Sanders Peirce, and further to emphasis the significance of mythic signs for the continuance of artistic and cultural idea including architecture. The contents of the paper is not that of architectural planning and design methodology, rather architectural philosophy and epistemology. Nevertheless, in regard to architecture, the research will, against today's un-discriminated use of symbolic motifs and instrumental representation of form, suggest a concrete architectural and aesthetic theory of myth and sign, especially of the relationship between the idea of semiology and the function of cultural continuity.

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The influence of graphene platelet with different dispersions on the vibrational behavior of nanocomposite truncated conical shells

  • Khayat, Majid;Baghlani, Abdolhossein;Dehghan, Seyed Mehdi;Najafgholipour, Mohammad Amir
    • Steel and Composite Structures
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    • v.38 no.1
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    • pp.47-66
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    • 2021
  • This work addresses the free vibration analysis of Functionally Graded Porous (FGP) nanocomposite truncated conical shells with Graphene PLatelet (GPL) reinforcement. In this study, three different distributions for porosity and three different dispersions for graphene platelets have been considered in the direction of the shell thickness. The Halpin-Tsai equations are used to find the effective material properties of the graphene platelet reinforced materials. The equations of motion are derived based on the higher-order shear deformation theory and Sanders's theory. The Fourier Differential Quadrature (FDQ) technique is implemented to solve the governing equations of the problem and to obtain the natural frequencies of the truncated conical shell. The combination of FDQ with higher-order shear deformation theory allows a very accurate prediction of the natural frequencies. The precision and reliability of the proposed method are verified by the results of literature. Moreover, a wide parametric study concerning the effect of some influential parameters, such as the geometrical parameters, porosity distribution, circumferential wave numbers, GPLs dispersion as well as boundary restraint conditions on free vibration response of FGP-GPL truncated conical shell is also carried out and investigated in detail.

Free vibration analysis of functionally graded cylindrical shells with different shell theories using semi-analytical method

  • Khayat, Majid;Dehghan, Seyed Mehdi;Najafgholipour, Mohammad Amir;Baghlani, Abdolhossein
    • Steel and Composite Structures
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    • v.28 no.6
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    • pp.735-748
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    • 2018
  • In this study, the semi-analytical finite strip method is adopted to examine the free vibration of cylindrical shells made up of functionally graded material. The properties of functionally graded shells are assumed to be temperature-dependent and vary continuously in the thickness direction according to a simple power law distribution in terms of the volume fraction of ceramic and metal. The material properties of the shells and stiffeners are assumed to be continuously graded in the thickness direction. Theoretical formulations based on the smeared stiffeners technique and the classical shell theory with first-order shear deformation theory which accounts for through thickness shear flexibility are employed. The finite strip method is applied to five different shell theories, namely, Donnell, Reissner, Sanders, Novozhilov, and Teng. The approximate procedure is compared favorably with three-dimensional finite elements. Finally, a detailed numerical study is carried out to bring out the effects of power-law index of the functional graded material, stiffeners, and geometry of the shells on the difference between various shell theories. Finally, the importance of choosing the shell theory in simulating the functionally graded cylindrical shells is addressed.

THIN-FILM-COATED DETECTORS FOR NEUTRON DETECTION

  • McGregor Douglas S.;Gersch Holly K.;Sanders Jeffrey D.;Klann Raymond T.;Lindsay John T.
    • Journal of Radiation Protection and Research
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    • v.26 no.3
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    • pp.167-175
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    • 2001
  • Semiconductor diode detectors coated with neutron reactive material are presently under investigation for various uses, such as remote sensing of thermal neutrons, fast neutron counting, and thermal neutron radiography. Theory indicates that single-coated devices can yield thermal neutron efficiencies from 4% to 11 %, which is supported by experimental evidence. Radiation endurance measurements indicate that the devices function well up to a limiting thermal neutron fluence of $10^{13}/cm^2$, beyond which noticeable degradation occurs. Thermal neutron contrast images of step wedges and simple phantoms, taken with dual in-line pixel devices, show promise for thermal neutron imaging detectors.

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A Study on User Characteristics Reflected in Semiotic Process of Web-Based MMORTS (웹기반 MMORTS 기호작용의 사용자 특성 연구)

  • Yoon, Sun-Mi
    • Journal of Korea Game Society
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    • v.11 no.3
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    • pp.21-30
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    • 2011
  • The form of web-based MMORTS game has changed the way users recognize games. This paper focuses fact that users' semiosis in MMORTS game shows different aspects from MMORPG game and to analyze it through theory of Charles Sanders Peirce. Users in MMORTS make a semiotic process in a wide range of ways including keeping avatars at a distance, reading index mark, and inferring through symbol marks. It leads to call a user in web-based MMORTS an administrator, symbol interpreter, and strategist.

Frequency Response Analysis of Cylindrical Shells Conveying Fluid Using Finite Element Method

  • Seo Young-Soo;Jeong Weui-Bong;Yoo Wan-Suk;Jeong Ho-Kyeong
    • Journal of Mechanical Science and Technology
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    • v.19 no.2
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    • pp.625-633
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    • 2005
  • A finite element vibration analysis of thin-walled cylindrical shells conveying fluid with uniform velocity is presented. The dynamic behavior of thin-walled shell is based on the Sanders' theory and the fluid in cylindrical shell is considered as inviscid and incompressible so that it satisfies the Laplace's equation. A beam-like shell element is used to reduce the number of degrees-of-freedom by restricting to the circumferential modes of cylindrical shell. An estimation of frequency response function of the pipe considering of the coupled effects of the internal fluid is presented. A dynamic coupling condition of the interface between the fluid and the structure is used. The effective thickness of fluid according to circumferential modes is also discussed. The influence of fluid velocity on the frequency response function is illustrated and discussed. The results by this method are compared with published results and those by commercial tools.

An Analysis on the Underwater Sound Radiation from Finite Cylindrical Shell with Stiffeners (유한 보강 원통형 셸 구조에 의한 수중 방사소음 해석)

  • 전재진;정우진
    • Journal of KSNVE
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    • v.6 no.6
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    • pp.717-726
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    • 1996
  • In this report, the underwater sound radiation from finite cylindrical shell with stiffeners which is the basic configuration of submerged vehicle is studied analytically and experimentally. The shell vibrations are obtained by using the shell theory of Sanders-Koitter. The stiffeners and modeled for I-type and the stiffness matrices are obtained by using beam model. In the analytical stuides, the vibrations of cylindrical shell are expressed by using cosine series expansions to consider the arbitrary end boundary conditions. It is agree to the theoretical and experimental results well.

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Vibration Analysis for Partially Immersed Shell Structure in Water with Gap from Bottom (부분적으로 물에 잠겨있는 Shell 구조물의 바닥면과 거리변화에 따른 진동해석 연구)

  • Koo, Jae-R.;Kwak, Moon-K.;Song, Oh-S.;Bae, Chun-H.
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.21 no.10
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    • pp.905-915
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    • 2011
  • The free flexural vibration of a hanged clamped-free cylindrical shell partially submerged in water with gap from bottom is investigated. The fluid is assumed to be inviscid and irrotational. The cylindrical shell is modeled by using the Rayleigh-Ritz method based on the Sanders shell theory. The kinetic energy of the fluid is derived by solving the boundary-value problem related to the fluid motion. The natural vibration characteristics of the partially submerged cylindrical shell are discussed with respect to the added virtual mass approach. In this study, experiments were carried out to confirm theoretical results. It was found that theoretical prediction is in good agreement with experimental results.