Post-buckling analysis of shear-deformable composite beams using a novel simple two-unknown beam theory

Kaci, Abdelhakim,Houari, Mohammed Sid Ahmed,Bousahla, Abdelmoumen Anis,Tounsi, Abdelouahed,Mahmoud, S.R. Techno-Press 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.65 No.5

In this paper, an exact analytical solution is developed for the analysis of the post-buckling non-linear response of simply supported deformable symmetric composite beams. For this, a new theory of higher order shear deformation is used for the analysis of composite beams in post-buckling. Unlike any other shear deformation beam theories, the number of functions unknown in the present theory is only two as the Euler-Bernoulli beam theory, while three unknowns are needed in the case of the other beam theories. The theory presents a parabolic distribution of transverse shear stresses, which satisfies the nullity conditions on both sides of the beam without a shear correction factor. The shear effect has a significant contribution to buckling and post-buckling behaviour. The results of this analysis show that classical and first-order theories underestimate the amplitude of the buckling whereas all the theories considered in this study give results very close to the static response of post-buckling. The numerical results obtained with the novel theory are not only much more accurate than those obtained using the Euler-Bernoulli theory but are almost comparable to those obtained using higher order theories, Accuracy and effectiveness of the current theory.

SOCIAL MEDIA EFFECTIVENESS USING WEB ANALYTICS

Kacy Kim,Sukki Yoon,Yung Kyun Choi,Younghwa Lee 글로벌지식마케팅경영학회 2016 Global Marketing Conference Vol.2016 No.7

This study is intended to provide marketing practitioners with an overview of web analytics to explore the issue of how to define and measure the effectiveness of social media through analyzing the various activities of current/potential consumers as well as provide a comprehensive analysis of the effectiveness of digital content marketing using social media. These analytics answer broad questions about which types of social media metrics are best at referring traffic, about conversations at the organization’s website, and about comparing different social media channels, such as Facebook and Twitter in this study. The major goal of this study is to demonstrate the value of businesses’ efforts and to optimize their digital/social marketing strategy using web analytics. Based on this goal three research questions were identified: (1) can the model identify social media performance variables that are related to audience response which can be represented by website traffic?; (2) which social media sties are driving traffic to a firm’s website, specifically in B2B environment?; and (3) can the model provide insight into the importance of those variables? These analytics employ time series analysis to specifically address activities in SNSs that effectively drive traffic to a website and accomplish business goals. This study is one of the first empirical investigations in the marketing communication field related to measuring social media’s effectiveness.

HOW COMPLEXITY-INDUCED CONSTRUAL AFFECTS THE PERCEPTION OF PROMOTIONAL MESSAGES

Kacy Kim,Sukin Kim,Gabrielle Corner,Sukki Yoon 글로벌지식마케팅경영학회 2018 Global Marketing Conference Vol.2018 No.07

When consumers are faced with various discounts, they are likely to find some easier to comprehend than others and this degree of difficulty will impact purchase decisions. This study explains complexity as a dimension of psychological distance using different types of discounts. Current research examines that easy-to-process discounts appear near and difficult-to-process discounts appear far. Applying construal level theory, this research investigates that the dollar discount leads to higher likeability of the attribute-appeal message and the percent discount lead to higher likeability of the benefit-appeal message. The dollar discount is low-level construal, as is an attribute message (i.e., how approach) whereas the percentage discount is high-level construal like a benefit message (i.e., why approach).

PRICING TRANSPARENCY IN INTERNATIONAL RETAILING

Kacy Kim,Yuhosua Ryoo,Srdan Zdravkovic,Sukki Yoon 글로벌지식마케팅경영학회 2023 Global Marketing Conference Vol.2023 No.07

This study examines the impact of price transparency—specifically the disclosure of cost breakdown—on brand attitudes and purchase intentions. The findings suggest that pricing transparency generally has a positive effect on attitudes and purchase intentions. However, pricing transparency might backfire, and thus reverse the effect, for luxury products originating from a high equity country (e.g., a fashion brand from Italy), but not for luxury and non-luxury products originating from a low equity country (e.g., a fashion brand from China). Luxury retailers in a high equity country should take extra caution before adopting price transparency

Effects of temperature on the evolution of stresses at the stem cement interface

Kaci, Djafar Ait,Moulgada, Abdelmadjid,Achache, Habib,Bounoua, Noureddine Techno-Press 2019 Advances in computational design Vol.4 No.3

The insertion of femoral implants is the most important phase for surgeons, given the characteristics of the cement during its mixing phase, generating residual stresses of thermal origin that increase the different stresses induced in the bone cement. The aim of our study is to determine the different stresses that affect the cement and more particularly at the cement-implant interface for different temperatures, and to make a comparison with the cement at ambient temperature. It was concluded that, there are a large concentration of stresses in the proximal part of the cement. For normal stresses, the bone cement is affected by stresses of tension and compression due to the effect of polymerization and the contraction of the cement.

ZOOM-IN, ZOOM-OUT: THE CONGRUENCE EFFECT BETWEEN DYNAMIC DISTANCE AND GEOGRAPHIC DISTANCE ON TRAVEL DESTINATION RECOMMENDATION

Kacy Kim,Qian Xu,Sukki Yoon 글로벌지식마케팅경영학회 2018 Global Marketing Conference Vol.2018 No.07

This research examined whether the (in)congruence between the geographical distance between the viewer and the destination, and the dynamic distance experienced via zoomin and zoom-out affects the recommendation likelihood of the travel destination. Specifically, when the viewer’s motivation is utilitarian (e.g., travelling for work), we expect the congruence effect (H1): a higher recommendation likelihood when the geographic distance is congruent with the dynamic distance; that is, the viewer is more likely to recommend the travel destination when the destination is geographically far away from (close to) with a zoom-out (zoom-in) view. By contrast, when the viewer’s motivation is hedonic (e.g., travelling for fun), we expect the incongruence effect (H2): a higher recommendation likelihood when the geographic distance is incongruent with the dynamic distance; that is, the viewer is more likely to recommend the travel destination when the destination is geographically far away from (close to) with a zoom-in (zoomout) view. We test these ideas in an experimental study.

Impact of composite patch on the J-integral in adhesive layer for repaired aluminum plate

Kaci, D. Ait,Madani, K.,Mokhtari, M.,Feaugas, X.,Touzain, S. Techno-Press 2017 Advances in aircraft and spacecraft science Vol.4 No.6

The aim of this study is to perform a finite element analysis of the Von Mises stresses distribution in the adhesive layer and of the J-Integral for a damaged plate repaired by a composite patch. Firstly, we study the effect of the fiber orientation, especially the position of the layers that have orientation angle different of $0^{\circ}$ from the first layer which is in all cases of our study oriented at ($0^{\circ}$) on the J-Integral. Secondly, we evaluate the effects of the mechanical properties of the patch and the use of a hybrid patch on the reduction of stresses distribution and J-Integral. The results show clearly that the stacking sequence for the composite patch must be selected to absorb optimally the stresses from the damaged area and to position the various layers of the composite under the first layer whose fibers orientation will remain in all cases equal to $0^{\circ}$. The use of a hybrid composite reduces significantly the J-Integral and the stresses in both damaged plate and the adhesive layer.

Nonlinear cylindrical bending analysis of E-FGM plateswith variable thickness

Abdelhakim Kaci,Khalil Belakhdar,Abdelouahed Tounsi,El Abbes Adda Bedia 국제구조공학회 2014 Steel and Composite Structures, An International J Vol.16 No.4

This paper presents a study of the nonlinear cylindrical bending of an exponential functionally graded plate (simply called E-FG) with variable thickness. The plate is subjected to uniform pressure loading and his geometric nonlinearity is introduced in the strain-displacement equations based on Von-Karman assumptions. The material properties of functionally graded plates, except the Poisson's ratio, are assumed to vary continuously through the thickness of the plate in accordance with the exponential law distribution; and the solution is obtained using Hamilton's principle for constant plate thickness. In order to analyze functionally graded plate with variable thickness, a numerical solution using finite difference method is used, where parabolic variation of the plate thickness is studied. The results for E-FG plates are given in dimensionless graphical forms; and the effects of material and geometric properties on displacements and normal stresses through the thickness are determined.

Nonlinear cylindrical bending of functionally graded carbon nanotube-reinforced composite plates

Abdelhakim Kaci,Abdelouahed Tounsi,Karima Bakhti,El Abbas Adda Bedia 국제구조공학회 2012 Steel and Composite Structures, An International J Vol.12 No.6

In this paper, the nonlinear cylindrical bending of simply supported, functionally graded nanocomposite plates reinforced by single-walled carbon nanotubes (SWCNTs), is studied. The plates are subjected to uniform pressure loading in thermal environments and their geometric nonlinearity is introduced in the strain–displacement equations based on Von-Karman assumptions. The material properties of SWCNTs are assumed to be temperature-dependent and are obtained from molecular dynamics simulations. The material properties of functionally graded carbon nanotube-reinforced composites (FG-CNTCRs) are assumed to be graded in the thickness direction, and are estimated through a micromechanical model. The governing equations are reduced to linear differential equation with nonlinear boundary conditions yielding a simple solution procedure. Numerical results are presented to show the effect of the material distribution on the deflections and stresses.

Post-buckling analysis of shear-deformable composite beams using a novel simple two-unknown beam theory

Abdelhakim Kaci,Mohammed Sid Ahmed Houari,Abdelmoumen Anis Bousahla,Abdelouahed Tounsi,S. R. Mahmoud 국제구조공학회 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.65 No.5

In this paper, an exact analytical solution is developed for the analysis of the post-buckling non-linear response of simply supported deformable symmetric composite beams. For this, a new theory of higher order shear deformation is used for the analysis of composite beams in post-buckling. Unlike any other shear deformation beam theories, the number of functions unknown in the present theory is only two as the Euler-Bernoulli beam theory, while three unknowns are needed in the case of the other beam theories. The theory presents a parabolic distribution of transverse shear stresses, which satisfies the nullity conditions on both sides of the beam without a shear correction factor. The shear effect has a significant contribution to buckling and post-buckling behaviour. The results of this analysis show that classical and first-order theories underestimate the amplitude of the buckling whereas all the theories considered in this study give results very close to the static response of post-buckling. The numerical results obtained with the novel theory are not only much more accurate than those obtained using the Euler-Bernoulli theory but are almost comparable to those obtained using higher order theories, Accuracy and effectiveness of the current theory.