• Steel and Composite Structures
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• v.37 no.1
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• pp.99-115
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• 2020

This article deals with the dynamic analysis in pad concrete foundation containing Silica nanoparticles (SiO₂) subject to seismic load. In order to control the foundation smartly, a piezoelectric layer covered the foundation. The weight of the building by a column on the foundation is assumed with an external force in the middle of the structure. The foundation is located in soil medium which is modeled by spring elements. The Mori-Tanaka law is utilized for calculating the equivalent mechanical characteristics of the concrete foundation. The Kevin-Voigt model is adopted to take into account the structural damping. The concrete structure is modeled by a thick plate and the governing equations are deduced using Hamilton's principle under the assumption of higher-order shear deformation theory (HSDT). The differential quadrature method (DQM) and the Newmark method are applied to obtain the seismic response. The effects of the applied voltage to the smart layer, agglomeration and volume percent of SiO₂ nanoparticles, damping of the structure, geometrical parameters and soil medium of the structure are assessed on the dynamic response. It has been demonstrated by the numerical results that by applying a negative voltage, the dynamic deflection is reduced significantly. Moreover, silica nanoparticles reduce the dynamic deflection of the concrete foundation.

• Structural Engineering and Mechanics
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• v.64 no.4
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• pp.403-411
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• 2017

In this article, analytical solution for free vibration of micro composite laminated beam on elastic medium based on modified couple stress are presented. The surrounding elastic medium is modeled as the Winkler elastic foundation. The governing equations and boundary conditions are obtained by using the principle of minimum potential energy for EulerBernoulli beam. For investigating the effect of different parameters including material length scale, beam thickness, some numerical results on different cross ply laminated beams such as (90,0,90), (0,90,0), (90,90,90) and (0,0,0) are presented on elastic medium. Free vibration analysis of a simply supported beam is considered utilizing the Fourier series. Also, the fundamental frequency is obtained using the principle of Hamilton for four types of cross ply laminations with hinged-hinged boundary conditions and different beam theories. The fundamental frequency for different thin beam theories are investigated by increasing the slenderness ratio and various foundation coefficients. The results prove that the modified couple stress theory increases the natural frequency under the various foundation for free vibration of composite laminated micro beams.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.2
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• pp.180-186
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• 1999

Conformal methods such as staircase approximation and effective medium theory have been used to model arbitrary dielectric surfaces in Cartesian FDTD(finite-difference time-domain) grids. However, the staircase approximation doesn't guarantee accurate results and the effective medium theory cannot be applied for frequency dispersive medium. In this paper, a simple conformal method is introduced for analyzing arbitrary dielectric surfaces. These arbitrarily shaped dielectric surfaces make nonuniformly filled FDTD cells. E(H)-field in a nonuniformly filled FDTD cell is calculated by considering the cell as the combination of two kinds of uniformly filled cells whose material boundaries are normal and parallel to the E(H)-field in the cell. TM scattering from a rotated 2-D dielectric and a ferrite square cylinder is analyzed to show the accuracy of the proposed method.

• Korean Management Science Review
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• v.30 no.2
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• pp.11-30
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• 2013

Small and medium-sized enterprises (SMEs) constitute an important part of current industrial economies. Information technologies can be useful strategic weapons for SMEs by enhancing their competitiveness. Categorized as one kind of cloud computing, SaaS is a computing resource and software sharing model which can be accessed via the Internet. Based on virtualization technology, SaaS is expected to improve the efficiency and quality of the IT service level in SMEs. This study attempts to identify the determinants of SaaS adoption intention among Korean SMEs. Through the lens of the theory of planned behavior, this study adopts technological, organizational, environmental factors to explore the determinants of cloud computing adoption intention. The research population is the SMEs that have been funded by the Korean government. Partial least square method was used for empirical analysis of 190 samples collected through on-line survey. The results show that the positive attitude is influenced by business process improvements. Vender support and top management support are positively associated with subjective norm. Vendor support, top management support can relieve perceived behavior control factors. Government support directly influences adoption intention of cloud computing. These findings can provide useful strategy for both SMEs and vendors of SaaS.

• ETRI Journal
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• v.36 no.6
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• pp.1041-1050
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• 2014

As the Internet Protocol TV (IPTV) service enters the broadcasting market, the competition intensifies. This paper explains the factors influencing new media subscription and their influential differences on IPTV and digital cable TV (DCTV). We use the information systems success model and gratification opportunity theory to develop our research model. We sample 621 people and collect their responses through web-based measuring software. Structural model analysis shows that the willingness to subscribe to a new broadcasting medium is influenced by three characteristics of the medium: media richness, interactivity, and video quality. Multigroup analysis reveals that motivation to use a medium partially differs between IPTV and DCTV. This research concludes that the IPTV service is not attractive enough to act as a substitute for the already existing DCTV. In addition, for the IPTV service to proliferate, its business model should be promoted with new and differentiated revenue structures and services. The managerial implications in this study help new media businesses set business goals and product functionality, and allocate resources for the continued diffusion of IPTV.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.637-643
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• 2021

The study examines the influence of the five pillars of inclusive financing on the empowerment of micro-, small- and medium-sized enterprises (MSMEs) and the influence of institutional conditions on the empowerment of MSMEs. This study uses primary and secondary data. The population of the study are MSMEs; the is a total of 930,620 MSMEs in Jakarta. Owners of micro-, small- and medium-sized enterprises is a good population to be measured because they are the main actors that know exactly the challenges and the obstacles in doing business addressing problems faced in inclusive financing, which is related to the purpose of the study. The research borrows from finance and entrepreneurial theories for model design. The results of the study show that all the variables are significant and positive in the efforts to finance MSMEs in Indonesia, which means that financial education plays an important role in the sustainability of financial inclusion. The financial theory, developed to explain financing at the company level, needs to be adapted to the entrepreneurial situation, so that it can explain the behavior of small businesses. This means that, with correct financial knowledge, financial inclusion plays an important role in the sustainability of MSMEs in Indonesia.

• Interaction and multiscale mechanics
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• v.5 no.1
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• pp.13-26
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• 2012

In this paper, the wave propagation in a generalized thermo elastic plate embedded in an elastic medium (Winkler model) is studied based on the Lord-Schulman (LS) and Green-Lindsay (GL) generalized two dimensional theory of thermo elasticity. Two displacement potential functions are introduced to uncouple the equations of motion. The frequency equations that include the interaction between the plate and foundation are obtained by the traction free boundary conditions using the Bessel function solutions. The numerical calculations are carried out for the material Zinc and the computed non-dimensional frequency and attenuation coefficient are plotted as the dispersion curves for the plate with thermally insulated and isothermal boundaries. The wave characteristics are found to be more stable and realistic in the presence of thermal relaxation times and the foundation parameter. A comparison of the results for the case with no thermal effects shows well agreement with those by the membrane theory.

• Steel and Composite Structures
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• v.36 no.6
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• pp.617-629
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• 2020

The purpose of this paper is to depict the effect of rotation and initial stress on a magneto-thermoelastic medium with diffusion. The problem discussed within memory-dependent derivative in the context of the three-phase-lag model (3PHL), Green-Naghdi theory of type III (G-N III) and Lord and Shulman theory (L-S). Analytical expressions of the considered variables are obtained by using Laplace-Fourier transforms technique. Numerical results for the field quantities given in the physical domain and illustrated graphically in the absence and presence of a magnetic field, initial stress as well as the rotation. The differences in variable thermal conductivity are also presented at different parameter of thermal conductivity. The numerical results of the field variables are presented graphically to discuss the effect of various parameters of interest. Some special cases are also deduced from the present investigation.

• Geomechanics and Engineering
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• v.21 no.5
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• pp.447-459
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• 2020

This paper aims to investigate the effect of rotation on a micropolar thermoelastic medium with voids problem. The problem is assessed according to three-phase-lag model. The normal mode analysis used to obtain the analytical expressions of the considered variables. The non-dimensional displacement, temperature, Micro rotation, the change in the volume fraction field, and stress of the material are obtained and illustrated graphically. Comparisons are made with the results predicted by two theories; namely three- phase-lag model (3PHL) and Green-Naghdi theory of type III (G-N III). The considered variables were plotted for different values of the rotation parameter, the phase-lag of heat flux and the phase-lag of temperature. The numerical results reveal that the rotation and the phase-lag times significantly influence the distribution of the field quantities. Some particular cases of interest are deduced from the present investigation.

• Knowledge Management Research
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• v.12 no.4
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• pp.55-75
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• 2011

Scant attention has been given to analyzing how knowledge sourcing strategies affect firm performance in SMEs and what are the differences between SMEs and large firms in the patterns of knowledge sourcing strategies adoption. This study attempts to advance the current literature by examining the impact of knowledge sourcing strategies on SMEs performance. The empirical segment of our work is based on data on knowledge sourcing strategies of SMEs and organizational performance from a sample of 166 Korean firms. Our results indicate knowledge sourcing adoption patterns of SMEs are different from large firms. In addition, the results confirm that substitutability between internal- and external-oriented, person- and external-oriented sourcing strategies. This study sheds new light on knowledge management (KM) research by identifying the relationship between knowledge sourcing strategies and SMEs performance.