• Earthquakes and Structures
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• v.11 no.4
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• pp.563-582
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• 2016

The failure mechanism and maximum collapse load of masonry structures may change significantly under static and dynamic excitations depending on their internal arrangement and material properties. Hence, it is important to understand correctly the nonlinear behavior of masonry structures in order to adequately assess their safety and propose efficient strengthening measures, especially for historical constructions. The discrete element method (DEM) can play an important role in these studies. This paper discusses possible collapse mechanisms and provides a set of parametric analyses by considering the influence of material properties and cross section morphologies on the out of plane strength of masonry walls. Detailed modeling of masonry structures may affect their mechanical strength and displacement capacity. In particular, the structural behavior of stacked and rubble masonry walls, portal frames, simple combinations of masonry piers and arches, and a real structure is discussed using DEM. It is further demonstrated that this structural analysis tool allows obtaining excellent results in the description of the nonlinear behavior of masonry structures.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1997.04a
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• pp.177-184
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• 1997

The Component Mode Synthesis Method for the -vibration analysis can be applied to the large-scaled structures, which have difficulty in modeling because of their intricate shapes and boundary conditions and need much time in computational calculations. This paper uses the Component Mode Synthesis Method to analyze the free vibration for the steel box bridge having the large number of D.O.F as an example of the large structural system. By comparing the CMS method to the other method (FEM), this paper proves the accuracy of the solution in techniques and the efficiency in time.

• Journal of Korea Society of Digital Industry and Information Management
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• v.8 no.3
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• pp.199-212
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• 2012

This study focuses on the influence of followership on leadership and empowerment, and to verify based on the control variables taken in IT SME's to enhance competitiveness through innovation and improvement plan that have been taken. Because there can be a lot of information to be taken, the laws of Moderated Regression Multiple analysis(MMR) were used. Amos, due to the moderating effect of Structural Equation Modeling(SEM) has been employed to re-verify the results seen with Moderated Regression Multiple analysis. The paper focuses on determining whether transformational leadership or transactional leadership is effective as shown by the levels of empowerment derived from these two types of leadership under study. As a result, both the Moderated Regression Multiple analysis and structural equation model searched information on transformational and followership for empowerment having moderating effects. In the Moderated Regression Multiple analysis, results showed that empowerment for leadership in business in the regulation of followership role appeared not to be seen. However, using the structural equation modeling, moderating effects have been found.

• Journal of the Korean Institute of Intelligent Systems
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• v.21 no.3
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• pp.378-382
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• 2011

This paper develops the core competencies of manufacturing workers, analyze the consciousness structure on the core competencies. As the analyzing method of consciousness structure, ISM(Interpretive Structural Modeling) and FSM(Fuzzy Structural Modeling) are used to classify layers and determine the connection state. However, the element of each layer is frequently changed by data. This paper suggests the method with the point of view that the structure is determined basically and the connection state of the structure model is changeable depending on the method; first to determine structure model by ISM, second to determine connection by FSM. By using this method, the objective structure model, analyzing the consciousness on the core competencies of manufacturing workers, is suggested with specialist confirm.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.2
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• pp.163-170
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• 2008

The aeroelastic stability analysis of a soft-in-plane, composite hingeless rotor blade in hover and in forward flight has been performed by combining the mixed beam method and the aeroelastic analysis system that is based on a moderate deflection beam approach. The aerodynamic forces and moments acting on the blade are obtained using the Leishman-Beddoes unsteady aerodynamic model. Hamilton's principle is used to derive the governing equations of composite helicopter blades undergoing extension, lag and flap bending, and torsion deflections. The influence of key structural modeling issues on the aeroelastic stability behavior of helicopter blades is studied. The issues include the shell wall thickness, elastic couplings and the correct treatment of constitutive assumptions in the section wall of the blade. It is found that the structural modeling effects are largely dependent on the layup geometries adopted in the section of the blade and these affect on the stability behavior in a large scale.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.4
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• pp.326-330
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• 2004

This study is object to design and structural analysis of Leg Extension Machine. Design tool is AutoCAD and structural analysis of Leg Extension Machine using result from ANSYS Code. This structural analysis results, many variables such as boundary condition, constraint condition and load condition are considered.

• Journal of Internet Computing and Services
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• v.15 no.6
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• pp.77-84
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• 2014

The purpose of this study is to explore factors affecting the effect of e-learning, and to find out the casual relationship among these factors. Subjects are 2,091 students who have participated in e-learning based class during the period of second semester in 2013. Those of them, 1,732 students response to the survey questions. After gathering data, they are analyzed by using Confirmative Factor Analysis and Structural Equation Modeling. From the result of Confirmative Factor analysis, data have reduced four factors, and are named as four latent variables likes e-learning effect, contents satisfaction, managing assistant factor, and system functional factor. From the result of Structural Equation Modeling, it is known as the relation and impact among factors: (a) "managing assistant factor" affects to "contents satisfaction" directly. (b) "contents satisfaction" affects to "e-learning effect" directly. (c) "system function factor" affects directly to "contents satisfaction", but does not affect directly to "e-learning effect". (d) both "managing assistant factor" and "system function factor" have an indirect effect on "e-learning effect" via "contents satisfaction".

• Journal of Korean Society of Steel Construction
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• v.22 no.1
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• pp.99-108
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• 2010

This paper presents the results of a study that aimed to develop a module for auto connection modeling that can be applied to the structural details design and modeling phase. It was established that the steel connection library database from the structural analysis resulted from the consideration of the input parameters of the 3D modeling program and the guidelines for Korean standard steel connections. The module for the auto connection modeling in steel structures was developed by linking it with the established library database through the use of the OpenAPI software to prove that the developed module carried out the modeling of the six story (steel structure) office building. The productivity and efficiency of the module introduction was verified by comparing the conventional process and the proposed process.

• The Journal of Industrial Distribution & Business
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• v.10 no.5
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• pp.7-20
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• 2019

Purpose - This study provides appropriate procedures for EFA to help researchers conduct empirical studies by using PLS-SEM. Research design, data, and methodology - This study addresses the absolute and relative sample size criteria, sampling adequacy, factor extraction models, factor rotation methods, the criterion for the number of factors to retain, interpretation of results, and reporting information. Results - The factor analysis procedure for PLS-SEM consists of the following five stages. First, it is important to look at whether both the Bartlett test of sphericity and the KMO MSA meet the qualitative criteria. Second, PAF is a better choice of methodology. Third, an oblique technique is a suitable method for PLS-SEM. Fourth, a combined approach is strongly recommended to factor retention. PA should be used at the onset. Next, it is recommended using the K1 criterion. In addition, it is necessary to extract factors that increase the total variance explanatory power through the PVA-FS. Finally, it is appropriate to select an item with a factor loading into 0.5 or higher and a communality of 0.5. Conclusions - It is expected that the accurate factor analysis processed for PLS-SEM as previously presented will help us extract more precise factors of the structural model.

• Journal of KSNVE
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• v.2 no.2
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• pp.125-134
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• 1992

In this study, ti identify the dynamic characteristics of automobile steering system which consists of many components and joints, each component combined structure was analyzed using commercial structural package, ANSYS. And, the finite element method for each component and modeling method of several joints universal joint, bolt joint, bearing, etc. were studied. On the other hand, the experimental modal analysis was performed to compare with the results of the finite element analysis and joint modeling. The result shows very close agreement between two analysis. Also, it was found that the steeing column used in this experiment does not effect the low frequency mode of entire system. In addition, we found that constraint equations need to be considered in modeling universal joint. Since the stiffness effect of Urethane around wheel could be ignored, it can be modeled only with mass effect. In the end, it was found that dynamic characteristics of the entire steerintg system depends mainly upon the wheel characteristics.