• Structural Engineering and Mechanics
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• v.75 no.2
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• pp.193-209
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• 2020

This paper presents a new hyperbolic shear deformation plate theory including the stretching effect for free vibration of the simply supported functionally graded plates in thermal environments. The theory accounts for parabolic distribution of the transverse shear strains and satisfies the zero traction boundary conditions on the surfaces of the plate without using shear correction factors. This theory has only five unknowns, which is even less than the other shear and normal deformation theories. The present one has a new displacement field which introduces undetermined integral variables. Material properties are assumed to be temperature-dependent, and graded in the thickness direction according to a simple power law distribution in terms of the volume power laws of the constituents. The equation of motion of the vibrated plate obtained via the classical Hamilton's principle and solved using Navier's steps. The accuracy of the proposed solution is checked by comparing the present results with those available in existing literature. The effects of the temperature field, volume fraction index of functionally graded material, side-to-thickness ratio on free vibration responses of the functionally graded plates are investigated. It can be concluded that the present theory is not only accurate but also simple in predicting the natural frequencies of functionally graded plates with stretching effect in thermal environments.

• Structural Engineering and Mechanics
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• v.89 no.1
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• pp.1-11
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• 2024

This article introduces a novel analytical model for examining the impact of porosity on shear correction factors (SCFs) in functionally graded porous beams (FGPB). The study employs uneven and logarithmic-uneven modified porosity-dependent power-law functions, which are distributed throughout the thickness of the FGP beams. Additionally, a modified exponential-power law function is used to estimate the effective mechanical properties of functionally graded porous beams. The correction factor plays a crucial role in this analysis as it appears as a coefficient in the expression for the transverse shear stress resultant. It compensatesfor the assumption that the shear strain is uniform across the depth of the cross-section. By applying the energy equivalence principle, a general expression for static SCFs in FGPBs is derived. The resulting expression aligns with the findings obtained from Reissner's analysis, particularly when transitioning from the two-dimensional case (plate) to the one-dimensional case (beam). The article presents a convenient algebraic form of the solution and provides new case studies to demonstrate the practicality of the proposed formulation. Numerical results are also presented to illustrate the influence of porosity distribution on SCFs for different types of FGPBs. Furthermore, the article validates the numerical consistency of the mechanical property changesin FG beams without porosity and the SCF by comparing them with available results.

• Korean Journal of Human Ecology
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• v.8 no.1
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• pp.5-18
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• 2005

The purposes of this study were to identify brand image and advertising image perception maps of domestic make-up products. A self-administered questionnaire was used for data collection. KYST, CORAN and SPSS PC(Ver. 12.0) were used for data analysis. The results were as follows: 1. Brand images of Etude, Isa Knox, and Laneige were perceived as unique, stimulative, high quality, elegant, modern, and sophisticated. Brand image of Cathycat was perceived highly in high quality, elegant, modern, and sophisticated, but low in unique and stimulative. Brand image of Lac Vert was perceived high in unique and stimulative, but low in high quality, elegant, modern, and sophisticated. Brand images of Hercyna and Vov were the lowest. 2. Advertisement images of Etude was perceived as modern, sophisticated, familiar, and unique, but Lac Vert was perceived adversely, Advertising images of Laneigne and Isa Knox were high in modern, sophisticated and familiar, but low in uniqueness. And advertising images of Hercyna, Cathycat, and Vov were perceived as modern, sophisticated, and familiar.

• Steel and Composite Structures
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• v.36 no.6
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• pp.643-656
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• 2020

This article presents a comprehensive static analysis of simply supported cross-ply carbon nanotubes reinforced composite (CNTRC) laminated nanobeams under various loading profiles. The nonlocal strain gradient constitutive relation is exploited to present the size-dependence of nano-scale. New higher shear deformation beam theory with hyperbolic function is proposed to satisfy the zero-shear effect at boundaries and parabolic variation through the thickness. Carbon nanotubes (CNTs), as the reinforced elements, are distributed through the beam thickness with different distribution functions, which are, uniform distribution (UD-CNTRC), V- distribution (FG-V CNTRC), O- distribution (FG-O CNTRC) and X- distribution (FG-X CNTRC). The equilibrium equations are derived, and Fourier series function are used to solve the obtained differential equation and get the response of nanobeam under uniform, linear or sinusoidal mechanical loadings. Numerical results are obtained to present influences of CNTs reinforcement patterns, composite laminate structure, nonlocal parameter, length scale parameter, geometric parameters on center deflection ad stresses of CNTRC laminated nanobeams. The proposed model is effective in analysis and design of composite structure ranging from macro-scale to nano-scale.

• Steel and Composite Structures
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• v.45 no.6
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• pp.839-850
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• 2022

This paper presents an analytical solution to study the combined effect of non-local and stretching effect on the vibration of advanced functionally graded (FG) nanoplates. A new quasi-3D plate theory is presented; there are only five unknowns and any shear correction factor is used. A new displacement field with a new shear warping function is proposed. The equilibrium equations of the FG nanoplates are obtained using the Hamilton principle and solved numerically using the Navier technique. The material properties of functionally graded nanoplates are presumed to change according to the power-law distribution of ceramic and metal constituents. The numerical results of this work are compared with those of other published results to indicate the accuracy and convergence of this theory. Hence, a profound parameterstudy is also performed to show the influence of many parameters of the functionally graded nanoplates on the free vibration responses is investigated.

• Structural Engineering and Mechanics
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• v.86 no.3
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• pp.373-384
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• 2023

The main objective of this research work is to present analytical solutions for the thermoelastic bending analysis of sandwich plates made of functionally graded materials with an arbitrary gradient. The governing equations of equilibrium are solved for a functionally graded sandwich plates under the effect of thermal loads. The transverse shear and normal strain and stress effects on thermoelastic bending of such sandwich plates are considered. Field equations for functionally graded sandwich plates whose deformations are governed by either the shear deformation theories or the classical theory are derived. Displacement functions that identically satisfy boundary conditions are used to reduce the governing equations to a set of coupled ordinary differential equations with variable coefficients. The results of the shear deformation theories are compared together. Numerical results for deflections and stresses of functionally graded metal-ceramic plates are investigated.

• Geomechanics and Engineering
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• v.37 no.2
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• pp.109-122
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• 2024

Standard triaxial cells are commonly used to measure the mechanical behavior of saturated soils. However, this type of standard system is difficult to use for unsaturated soil specimens since it cannot measure the changes in the pore-air volume and pressure. This paper proposes to extend the measurement possibilities of the standard triaxial testing device in a simple way and to adapt it to partially saturated soils. The system is supplied by two hygrometers installed at each end of the cylindrical unsaturated specimen to measure local relative humidity, which allows the derivation of suction. The volumetric strain of the specimen is calculated by analyzing digital photos captured from the outside of the transparent cell wall. Specimens made of kaolin clay, having different hydraulic properties, were tested to verify the reliability of the measurements, and thus, the relevance of the proposed techniques to study the mechanical behavior of unsaturated soils.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.308-315
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• 2009

The activities of flower color biosynthesis-controlling enzymes, flavonoid 3'hydroxy lase (F3'H) and dihydroflavonol 4-reductase (DFR), were analyzed in Llium longijlorum and 11 lily cultivars using biochemical and enzymological methods. Dihydroquercetin (DHQ) product was synthesized by F3'H using dihydrokaempferol (DHK) as a substrate in Lilium longiflorum. F3'H activity was also detected in the eight cultivars tested. The substrate-specific activity of F3'H was observed because eridictiol (ERI), which uses naringenin (NAR) as a substrate, was not detected in the tested cultivars. Leucocyanidin (LCy) product was synthesized by DFR using DHQ as a substrate in Lilium longiflorum. DFR activity was also detected in 'Le Reve', 'Montreux', 'Monte Negro', 'Etude', 'Acapulco', and 'Star Gazer', but not in 'Siberia', 'Royal Race', 'Nove Cento', 'Elite', and 'Cannes'. Substrate-specific activity of DFR was observed because leucopelargonidin (LPg), which uses DHK as a substrate, was not detected in the tested cultivars.

• Structural Engineering and Mechanics
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• v.89 no.3
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• pp.225-238
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• 2024

In this paper, a quasi-3D hyperbolic shear deformation theory for the bending responses of a functionally graded (FG) porous micro-beam is based on a modified couple stress theory requiring only one material length scale parameter that can capture the size influence. The model proposed accounts for both shear and normal deformation effects through an illustrative variation of all displacements across the thickness and satisfies the zero traction boundary conditions on the top and bottom surfaces of the micro-beam. The effective material properties of the functionally graded micro-beam are assumed to vary in the thickness direction and are estimated using the homogenization method of power law distribution, which is modified to approximate the porous material properties with even and uneven distributions of porosity phases. The equilibrium equations are obtained using the virtual work principle and solved using Navier's technique. The validity of the derived formulation is established by comparing it with the ones available in the literature. Numerical examples are presented to investigate the influences of the power law index, material length scale parameter, beam thickness, and shear and normal deformation effects on the mechanical characteristics of the FG micro-beam. The results demonstrate that the inclusion of the size effects increases the microbeams stiffness, which consequently leads to a reduction in deflections. In contrast, the shear and normal deformation effects are just the opposite.

• Journal of architectural history
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• v.5 no.1 s.9
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• pp.113-122
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• 1996

Cette etude vise a reveler une verite du Nouveau Brutalisme des Smithson (Alison et Peter). Nous examinerons donc d'abord l'universalitf de leur oeuvre representatif, Ecole Secondaire de Hunstanton(projet, 1949; concours, 1950; construction, 1951-1954) et projet de Maison Soho a Londres(1952) comme un mouvement architectural. Et apres nous trouverons la faussete de leur but, realisation de l'ethique architecturale, sur ce mouvement en comparant les oeuvres des Smithson avec les deux constructions considerees souvent comme la categorie du Nouveau Brutalisme, la Calorie d'Art de l'Universite Yale(1951-1953) realisee par Louis I. Kahn(1901-1974) et le Centre Cuturelle de Georges-Pompodou(1971-1977) par Renzo Piano et Richard Rogers. En resultat, l'etique de Nouveau Brutalisme soutenue par les Smithson et defendue par Reyner Banham etait seulement pour cacher low limite architecturale et sa faiblesse. Ce mouvement etait aussi un mouvement personel plutot que general. On ne pourrait pas donc considerer les Smithson comme nouveaux brutalistes.