• Earthquakes and Structures
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• v.19 no.2
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• pp.103-117
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• 2020

The effect of the foundation size on the efficiency of seismic base isolation using a layer of stone pebbles is experimentally investigated. Four scaled models of buildings with different stiffnesses (from very stiff to soft) were tested, each with the so-called small and large foundation, and exposed to four different accelerograms (different predominant periods and durations). Tests were conducted so that the strains in the model remained elastic and afterwards the models were tested until collapse. Each model was tested for the case of the foundation being supported on a rigid base and on an aseismic layer. Compared to the smaller foundation, the larger foundation results in a reduced rocking effect, higher earthquake forces and lower bearing capacity of the tested models, with respectable efficiency (reduced strain/stress, displacement and increase of the ultimate bearing capacity of the model) for the considered seismic base isolation compared to the foundation on a rigid base.

• The Journal of Korean Physical Therapy
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• v.32 no.5
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• pp.277-282
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• 2020

Purpose: The main purposes of this study are to identify the degree of effect size and variables related to it, on the effect of physical therapy on shoulder adhesive capsulitis. Methods: This study were collected 8 studies published between 2010.01.01. and 2020.08.01. The Analysis result confirmed 16 effect size data, the random effect model was chosen because of the heterogeneity of the data. Results: First, full case showed the largest mean effect size 3.28 (p<0.001). Second, Size of the effect according to hands on+off intervention the 5.17 (p>0.344). Third, Number of participants showed 15 or more effect size 4.19 (p<0.002). intervention period showed 8 weeks effect size 5.12 (p>0.425). Number of intervention showed 14 or less effect size 3.99 (p>0.061). Publication type showed thesis effect size 4.34 (p<0.003). Finally, 'Trim and Fill' result confirmed that the calibration effect size is 1.71 (p<0.001). Conclusion: We were able to confirm that physical therapy had great effect on shoulders adhesive capsulitis, and that the effect differed according to the methods of intervention, the methods of evaluation.

• The Journal of Korean Physical Therapy
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• v.32 no.4
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• pp.222-227
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• 2020

Purpose: The primary purposes of this study were to identify the degree of the effect size and the variables related to it on the effects of physical therapy on myofascial pain syndrome. Methods: This study collected 15 studies published between 2008.01.01 and 2019.12.31. The Analysis results confirmed 57 effect size data. The random-effect model was chosen because of the heterogeneity of the data. Results: First, the full case showed the largest mean effect size of 2.03 (p<0.001). Second, the size of the effect, according to the handson intervention, was 2.74 (p<0.003). Third, the VAS showed an effect size of 2.30 (p<0.001). Fourth, the intervention period showed a 1- to 15-day effect size of 2.94 (p<0.001). The number of interventions showed a 6 to 10 effect size of 2.84 (p<0.006). The number of participants showed a 10 or less effect size of 2.66 (p<0.001). Finally, the 'Trim and Fill' result confirmed that the calibration effect size was 0.93 (p<0.001). Conclusion: Physical therapy had a great effect on myofascial pain syndrome in the neck and shoulders, and that the effect differed according to the methods of the intervention and the methods of evaluation.

• Journal of Distribution Science
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• v.13 no.8
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• pp.41-48
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• 2015

Purpose - This study's objective is to confirm the effects of the perceived relationship value, alternative attractiveness, and investment size on Korean food service franchisees' commitment, using an investment model. Among the three factors, the study examines which factors enhance or weaken the commitment in the franchising investment model. Research design, data, methodology - The data were collected from 495 franchisees and analyzed by a SEM (Structure Equation Model) using path analysis by SPSS 18.0 and AMOS 18.0. Results - 1) The perceived relationship value has a positive effect on franchisee commitment. 2) The alternative attractiveness has a negative effect on franchisee commitment. 3) The investment size has a positive effect on franchisee commitment. Conclusions - The findings show that the investment model can be adapted to franchising and confirms previous investment model study results. We can assume that the higher the perceived relationship value and the bigger the investment, the stronger the commitment, and the greater the alternative attractiveness, the weaker the commitment. These results offer managerial implications for a franchisor wanting to strengthen franchisee commitment.

• Magazine of the Korea Concrete Institute
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• v.11 no.2
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• pp.157-165
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• 1999

When the ultimate strength of a concrete flexural member is evaluated, the effect of member size is usually not considered. For various types of loading, however, the strength always decreases with the increment of member size. In this paper the size effect of a flexural compression member is investigated by experiments. For this purpose, a series of C-shaped specimens subjected to axial compressive load and bending moment was tested using three different sizes of specimens with a compressive strength of 528 kg/$cm^2$. According to test results the size effect on flexural compressive strength was apparent, and more distinct than that for uniaxial compressive strength of cylinders. Finally a model equation was derived using regression analyses with experimental data.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.239-244
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• 1999

The reduction phenomena of the compressive strength of concrete with respect to the size of specimens have been extensively investigated. However, adequate analysis technique have not been developed until now. Existing researches have shown that the larger member size, the smaller the strength. This indicated the necessity of nonlinear fracture mechanics theory in order to analyze the fracture behaviors of concrete. The are some models that predict the size effect of compressive strength of cylindrical specimens. Theses equations, however, are developed not considering the difference of fracturing mechanism which depends on both geometry of specimen and the strength level of concrete. In this paper, a model to predict compressive strength of cylindrical concrete specimens with respect to diameters, h/d ratios, and the strength level of concrete, is suggested. For this purpose, theoretical and statistical analyses are conducted. Experimental constants used in the model of new size effect are formulated in terms of strength levels of concrete based on existing experimental data.

• Steel and Composite Structures
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• v.22 no.6
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• pp.1301-1336
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• 2016

In this paper, the free vibrations of a short cylindrical nanotube made of piezoelectric material are studied based on the consistent couple stress theory and using the shear deformable cylindrical theory. This new model has only one length scale parameter and can consider the size effects of nanostructures in nanoscale. To model size effects in nanoscale, and considering the nanotube material which is piezoelectric, the consistent couple stress theory is used. First, using Hamilton's principle, the equations of motion and boundary condition of the piezoelectric cylindrical nanoshell are developed. Afterwards, using Navier approach and extended Kantorovich method (EKM), the governing equations of the system with simple-simple (S-S) and clamped-clamped (C-C) supports are solved. Afterwards, the effects of size parameter, geometric parameters (nanoshell length and thickness), and mechanical and electric properties (piezoelectric effect) on nanoshell vibrations are investigated. Results demonstrate that the natural frequency on nanoshell in nanoscale is extremely dependent on nanoshell size. Increase in size parameter, thickness and flexoelectric effect of the material leads to increase in frequency of vibrations. Moreover, increased nanoshell length and diameter leads to decreased vibration frequency.

• Informatization Policy
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• v.24 no.1
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• pp.48-78
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• 2017

In this study, to reveal determinant factors for degree of open data it conduct empirical analysis for ODB(Open Data Barometer) and OUR Index(Open, Useful, Reusable Government Data Index) that are global open data index among 26 countries. As a result of multiple regression analysis, First focus is on ODB. In the Model 1 with independent variables, e-Government, SW Market size and government efficacy are significantly positive effect for ODB. In the Model 2 with independent variables and moderating variable, e-Government, SW market size and social capital are significantly positive effect for ODB. In the Model 3 with independent variables, moderating variable and interaction term, e-Government and social capital are significantly positive effect for ODB. Second focus is on OUR Index. In the Model 1 and the Model 2 e-Government is significantly positive effect for OUR Index. In the Model, e-Government and SW market size ${\times}$ social capital(interaction term) are significantly positive effect for OUR Index. And in path analysis, only ODB alternative model show Government efficacy with social capital has full mediation effect. In OUR Index alternative model there is no mediation effect with social capital.

• New & Renewable Energy
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• v.2 no.2 s.6
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• pp.28-36
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• 2006

Numerical analysis of wind turbine scale effect was performed by using commercial CFD code, Fluent. For the numerical analysis of wind turbine, the three dimensional Navier-Stokes solver with various turbulence models was tested. As a turbulence mode, the realizable k-e turbulence model was selected for the simulation of wind turbines. To validate the present method, performance of NREL (National Renewable Energy Laboratory) Phase VI wind turbine model was analyzed and compared with its wind tunnel test and blind test data. Using the present method, numerical simulations for various size of wind tunnel models were carried out and characteristics were analyzed in detail. For wind tunnel test model, the size of nacelle may not be scaled down precisely because of available motor. The effect of nacelle size was also computed and analyzed though CFD simulation. The present results showed the good correlations in pre-stall region but much to be improved in post-stall region. In 2006 and 2007, the performance and the scale effect of standard wind turbine model will be tested in KARI(Korea Aerospace Research Institute) LSWT(Low Speed Wind Tunnel) and the present results will be validated with the wind tunnel data.

• Smart Structures and Systems
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• v.22 no.5
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• pp.527-546
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• 2018

This article presents an analysis into the nonlinear forced vibration of a micro cylindrical shell reinforced by carbon nanotubes (CNTs) with considering agglomeration effects. The structure is subjected to magnetic field and transverse harmonic mechanical load. Mindlin theory is employed to model the structure and the strain gradient theory (SGT) is also used to capture the size effect. Mori-Tanaka approach is used to estimate the equivalent material properties of the nanocomposite cylindrical shell and consider the CNTs agglomeration effect. The motion equations are derived using Hamilton's principle and the differential quadrature method (DQM) is employed to solve them for obtaining nonlinear frequency response of the cylindrical shells. The effect of different parameters including magnetic field, CNTs volume percent and agglomeration effect, boundary conditions, size effect and length to thickness ratio on the nonlinear forced vibrational characteristic of the of the system is studied. Numerical results indicate that by enhancing the CNTs volume percent, the amplitude of system decreases while considering the CNTs agglomeration effect has an inverse effect.