• Structural Engineering and Mechanics
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• 제63권4호
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• pp.439-446
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• 2017

This work proposes an original single variable shear deformation theory to study the buckling analysis of thick isotropic plates subjected to uniaxial and biaxial in-plane loads. This theory is built upon the classical plate theory (CPT) including the exponential function in terms of thickness coordinate to represent shear deformation effect and it involves only one governing differential equation. Efficacy of the present theory is confirmed through illustrative numerical examples. The obtained results are compared with those of other higher-order shear deformation plate theory results.

• Advances in aircraft and spacecraft science
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• 제5권6호
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• pp.671-689
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• 2018

Bending, buckling and free vibration responses of functionally graded (FG) higher-order beams resting on two parameter (Winkler-Pasternak) elastic foundation are studied using a new inverse hyperbolic beam theory. The material properties of the beam are graded along the thickness direction according to the power-law distribution. In the present theory, the axial displacement accounts for an inverse hyperbolic distribution, and the transverse shear stress satisfies the traction-free boundary conditions on the top and bottom surfaces of the beams. Hamilton's principle is employed to derive the governing equations of motion. Navier type analytical solutions are obtained for the bending, bucking and vibration problems. Numerical results are obtained to investigate the effects of power-law index, length-to-thickness ratio and foundation parameter on the displacements, stresses, critical buckling loads and frequencies. Numerical results by using parabolic beam theory of Reddy and first-order beam theory of Timoshenko are specially generated for comparison of present results and found in excellent agreement with each other.

• Structural Engineering and Mechanics
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• 제53권3호
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• pp.411-427
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• 2015

Based on linear elastic theory of quasicrystals, various equations and solutions for quasicrystal beams are deduced systematically and directly from plane problem of two-dimensional quasicrystals. Without employing ad hoc stress or deformation assumptions, the refined theory of beams is explicitly established from the general solution of quasicrystals and the Lur'e symbolic method. In the case of homogeneous boundary conditions, the exact equations and exact solutions for beams are derived, which consist of the fourth-order part and transcendental part. In the case of non-homogeneous boundary conditions, the exact governing differential equations and solutions under normal loadings only and shear loadings only are derived directly from the refined beam theory, respectively. In two illustrative examples of quasicrystal beams, it is shown that the exact or accurate analytical solutions can be obtained in use of the refined theory.

• Steel and Composite Structures
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• 제27권5호
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• pp.599-611
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• 2018

In this article a four unknown quasi-3D shear deformation theory for the bending analysis of functionally graded (FG) plates is developed. The advantage of this theory is that, in addition to introducing the thickness stretching impact (${\varepsilon}_z{\neq}0$), the displacement field is modeled with only four variables, which is even less than the first order shear deformation theory (FSDT). The principle of virtual work is utilized to determine the governing equations. The obtained numerical results from the proposed theory are compared with the CPT, FSDT, and other quasi-3D HSDTs.

• Advances in aircraft and spacecraft science
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• 제7권1호
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• pp.19-40
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• 2020

In the present study, a fifth-order shear and normal deformation theory using a polynomial function in the displacement field is developed and employed for the static analysis of laminated composite and sandwich simply supported spherical shells subjected to sinusoidal load. The significant feature of the present theory is that it considers the effect of transverse normal strain in the displacement field which is eliminated in classical, first-order and many higher-order shell theories, while predicting the bending behavior of the shell. The present theory satisfies the zero transverse shear stress conditions at the top and bottom surfaces of the shell. The governing equations and boundary conditions are derived using the principle of virtual work. To solve the governing equations, the Navier solution procedure is employed. The obtained results are compared with Reddy's and Mindlin's theory for the validation of the present theory.

• 대한한의학원전학회지
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• 제11권1호
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• pp.2-20
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• 1998

In the field of acupuncture and moxibustion, the theory of taboo of acupuncture and moxibustion on the basis of where the 'Qi and the soul of the men(人氣 人神)' exist became the foundation of the 'theory of chrono-acupunclure and moxibustion(時間性鍼灸法), that takes into account the thrift and retreatment of the Qi(氣) and the 'soul of the men' according to day and time. The fields of acupuncture and moxibustion in the theory of 'Yun Qi(運氣) which takes into account time space are the theories of the 'ZiWuLinZhu(子午流注)' and the 'LingGuiBaFa(靈龜八法)'. While the theory of the 'ZiWuLlnZhu' has the nature of time, 'LingGuiBaFa' has the nature of space comparatively. So the theory of 'Yun Qi' adopted and improved the time-space background that is the basis of the theory of the 'ZiWuLinZhu' and the 'LingGuiBaFa'.

• 대한한의학원전학회지
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• 제22권4호
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• pp.261-264
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• 2009

Gi(氣) transformation theory is the foundation of Traditional Chinese Medicine[TCM]. This theory matured during the period of "Hwangjenaegyeong(黃帝內經)", and later in the history of TCM was a source of significant impact on the development process and direction of general medical theory. The concept of "gi transformation[氣化]" mainly originates from the definition of the three levels which are nature, the relationship between nature and human, and the body's own metabolism, and is used to describe the usage and the resulting changes of 'gi(氣)'. Gi transformation possesses six characteristics which are permanence, universality, representationalism, directional, variability, and orderliness. The research of the concept and characteristics of gi transformation[氣化] in "Hwangjenaegyeong" will help identify the important academic value and practical significance of the formation of the basic theory of TCM as the result of the gi transformation theory, and highlight the unique characteristics of TCM.

• 한국주거학회논문집
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• 제11권3호
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• pp.9-18
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• 2000

The fuzzy theory is on the basis of understanding of the subjectivity and the ambiguity. The paradigm of the fuzzy theory is to explore a regularity from the subjectivity and the ambiguity. Nowadays, the fuzziness, the main concept of the fuzzy theory, is widely applied to a lot of fields as the theory which is positively accepted and actively interpreted. In the science, the fuzziness is officially called as multi-valence. On the other side, there exists the other theory called Han-ism which is presumed as a prototype of korean philosophy. The basic concept of the Han-ism - one, many, middle, same, about - includes the fuzziness. The purpose of this study is to unfold the interrelationship between the fuzzy theory and Han-ism, and furthermore, to interpretate the cultural phenomenon and architectural spaces in koreas traditional architecture with a viewpoint, the fuzziness of the Han-ism.

• 대한가정학회지
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• 제38권6호
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• pp.71-79
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• 2000

The purpose of this study was to investigate the relationship between preschoolers'theory of mind and parenting style. The mothers of 66 3- and 4-year-olds were given questionnaires eliciting information about parenting style, SES, number of younger and older siblings, the time child spends with mother. Three variables were positively correlated with theory of mind: age, number of older siblings, and affective parenting style. The time spent with mother was negatively correlated with theory of mind. Factors most strongly affecting theory of mind were child's age and mother's affective parenting style. The resets are consistent with recent research showing that parenting style may be important for theory of mind understanding.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2003년도 추계학술발표대회 논문집
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• pp.171-174
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• 2003

The Special orthotropic plate theory is used for analysis of panels made of steel girders and cross-beams, and made of reinforced concrete. The cross-sections of girders and cross-beams are WF types. The result is compared with that of the beam theory. According to the numerical examination given in this paper, the result by the plate theory is 2.43 times stiffer than that of beam theory, The result for the concrete slab in given for the practicing engineers.