• Journal of the Korea Society of Computer and Information
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• v.25 no.10
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• pp.193-201
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• 2020

This study is to evaluate the effectiveness of problem-solving ability by applying a team-based learning model to the classes of humanities and social science students, and to conduct a structural model analysis on the relationship between sub-factors. Team-based learning was conducted six times in six teams with 30 students in the second and third grades of the humanities and social sciences. The problem solving ability score of the target students was significantly higher after team-based learning and was statistically significant. There was no problem in normality with the latent variables, which are the sub-factors of problem solving ability, and the factor load value was statistically significant at the .001 level in the confirmatory factor analysis of the observed variables for the latent variables, which was a valid model. A good level of fitness was also shown in the verification of the fitness of the research model. As a result, it was analyzed that latent variables of cause analysis, problem clarification, planning execution, performance evaluation, and alternative development had an indirect or direct influence on each other.

• Coupled systems mechanics
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• v.9 no.4
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• pp.359-379
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• 2020

Due to susceptibility of bridges in the past earthquakes, vulnerability assessment and strengthening of bridges has gained a particular significance. The objective of the present study is to employ an analytical method for the development of fragility curves, as well as to investigate the effect of strengthening on the RC box-girder bridges. Since fragility curves are used for pre-and post-earthquake planning, this paper has attempted to adopt the most reliable modeling assumptions in order to increase the reliability. Furthermore, to acknowledge the interaction of soil, abutment and pile, the effect of different strengthening methods, such as using steel jacketing and FRP layers, the effect of increase in the bridge pier diameter, and the effect of vertical component of earthquake on the vulnerability of bridges in this study, a three-span RC box-girder bridge was modeled in 9 different cases. Nonlinear dynamic analyses were carried out on the studied bridges subjected to 100 ground motion records via OpenSEES platform. Therefore, the fragility curves were plotted and compared in the four damage states. The results revealed that once the interaction of soil and abutment and the vertical component of the earthquake are accounted for in the calculations, the median fragility is reduced, implying that the bridge becomes more vulnerable. It was also confirmed that steel jackets and FRP layers are suitable methods for pier strengthening which reduces the vulnerability of the bridge.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.3
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• pp.393-404
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• 2007

A concept of multi-layered database is proposed for the integrated operation of bridge information in this study. The multi-layered database is a logically integrated database composed of standardized information layers. The standardized information layers represent the data sets that can be unified, and they are defined by standardized information models. Classification system of bridge component was used as a basis of the multi-layered database, and code system based on the classification system was employed as a key integrator to manipulate the distributed data located on the different information layers. In addition, data level indicating priorities of information layers was defined to support strategic planning of the multi-layered database construction. As a proof of concept, a prototype of multi-layered database for object-oriented 3-D shape information and structural calculation document was built. Data consistency check of the semantically same data in the two different information layer was demonstrated, It is expected that the proposed concept can assure the integrity and consistency of information in the bridge information management.

• Korean Journal of Construction Engineering and Management
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• v.13 no.3
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• pp.78-88
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• 2012

Previous construction failure researches were focused on the utilization plan based on failure information and development of failure classification. However, it has limitation to set up the plan for prevention of construction failure due to the lack of the number of on-site staffs. In order to prevent effectively construction failure, a prevention plan should be established through quantitative evaluation of failure causes. The purpose of this study is to suggest the assessment method for selection Critical Management Factor(CMF) and to analyze the CMF on the apartment structural framework using FMEA(Failure Mode and Effective Analysis) which is one of the methods of quantitative evaluation. The element of risk evaluation separated degree of failure risk and prevention respectively. The assessment method for selection of CMF can be utilized for planning proactive solutions on the failure, and it can be also selected critical factors about each project phases, type of facility and construction work.

• Journal of Internet Computing and Services
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• v.11 no.6
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• pp.145-157
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• 2010

In this paper, we describe the design details and their implementation of a workflow model (or business process model) analysis system to be used for enhancing resource allocation efficiency and operational performance of enterprise workflows. In other word, the analysis works, proposed in this paper, on XPDL-based workflow models aim to verify the static aspects of the workflow models. Also, the system implemented in the paper is able to not only analyze structural patterns and resource allocation plans' efficiency of enterprise workflows modeled by the XPDL process definition language developed by the international standardization organization, WfMC, but also provide various forms of analytical reports. Conclusively, we strongly believe that the workflow analysis system developed in the paper enables workflow modelers to not only analyze and scrutinize structural patterns of their workflow models but also estimate their process resources assigning and planning measurements in order to improve accuracy, reliability and efficiency of enterprise workflows.

• Earthquakes and Structures
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• v.12 no.1
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• pp.1-12
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• 2017

Historical earthquakes have shown that successive seismic events may occur in regions of high seismicity. Such a sequence of earthquakes has the potential to increase the damage level of the structures, since any rehabilitation between the successive ground motions is practically impossible due to lack of time. Few studies about this issue can be found in literature, most of which focused their attention on the seismic response of SDOF systems or planar frame structures. The aim of the present study is to examine the impact of seismic sequences on the damage level of 3D multistorey R/C buildings with various structural systems. For the purposes of the above investigation a comprehensive assessment is conducted using three double-symmetric and three asymmetric in plan medium-rise R/C buildings, which are designed on the basis of the current seismic codes. The buildings are analyzed by nonlinear time response analysis using 80 bidirectional seismic sequences. In order to account for the variable orientation of the seismic motion, the two horizontal accelerograms of each earthquake record are applied along horizontal orthogonal axes forming 12 different angles with the structural axes. The assessment of the results revealed that successive ground motions can lead to significant increase of the structural damage compared to the damage caused by the corresponding single seismic events. Furthermore, the incident angle can radically alter the successive earthquake phenomenon depending on the special characteristics of the structure, the number of the sequential earthquakes, as well as the distance of the record from the fault.

• Journal of the Korean housing association
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• v.17 no.3
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• pp.61-69
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• 2006

Vertical vibrations on the slab of buildings are affected by types of vibration sources, transfer paths, and the material property and the size of members. Among these parameters, the vibration sources and the transfer path can not be controlled, but the property and the size of members can be controlled in the phase of design the members. In this study, the vibration responses according to the property and size of members were obtained by using a prediction program based on dynamic-stiffness matrix. Three parameters which are not usually considered as major factors for architecral planning were selected fur these analyses. They are the strength of materials, the thickness of wall and the thickness of slab. The ground vibration source located near a building was used as vibration input data in the analyses. This study has its originality on presenting appropriate property and size of structural members in order to reduce vertical vibration of slab in shear-wall structures. Analysing the results from the vibration estimation program according to the variations of parameters, the appropriate ratio among the sizes of structural members were proposed. From these results, the vibration level on the slab which is not constructed yet would be predicted and the vibration peak level can be reduced or shifted into the desirable frequency range. Therefore, the vertical vibration could be controlled in the phase of designing buildings.

• Journal of Advanced Research in Ocean Engineering
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• v.2 no.3
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• pp.150-157
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• 2016

When blocks are supported on a dock, huge reaction forces concentrated at the supports cause structural damage owing to local stress concentrations. Thus, the supports should be arranged to avoid local failure from the reaction forces by redistributing those forces. Docking analyses to determine the proper blocks and their support arrangements are introduced so that the local stresses are minimized to warrant the safety of the docking supports. Local stresses enforced by the support arrangement should be evaluated by finite element analysis (FEA). However, it is difficult to consider an accurate 3D geometry of the blocks in the finite element model because the structural design information is too complicated to determine within several days using the FEA model. This paper presents a simplified FE model to evaluate the safety of the arrangement of supports using a simplified grillage element. The grillage element can be efficiently used to obrain the reaction forces in docking analysis becasuse the reaction forces at the supports are enough to assess the safety of block. Since a simplified grillage model of the entire ship cannot accurately calculate the local stresses, an optimized modeling method based on the grillage element was introduced. The local reaction forces obtained by the proposed approach and three-dimensional FEA were discussed for typical types of ships. It is shown that the reaction forces obtained by the present grillage model are in reasonably good agreement with the FEA model.

• Journal of Korean Association for Spatial Structures
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• v.6 no.3 s.21
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• pp.111-121
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• 2006

Beam String Structure is a structure system that is composed with beam, strut and string, and the structural capacity of this structure system is enhanced by introducing prestress force in string and controling the stress and deformation of beam. Researching on the established studies and examples, character and composition methods of Beam String Structure was investigated. At the result, It was examined that the design elements of the system are shape and rise of beam, sag of string, plan arrangement and the composition and number of strut, in addition, detailed composition methods of the design elements were represented. Also, it was showed that the method to form the individual mechanism against additional load can be employed in order to reduce stress of Beam String Structure under the heavy additional load.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.65 no.1
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• pp.31-40
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• 2016

The purpose of this study is to dimensionally examine the factors of policy changes by applying the ACMS model to KEPCO's structural reorganization privatization policies and study its implications. As a result of the analysis, among the external variables that affect as a financial source or restriction to advocates, all areas except for the difference in opinion of the people as well as policy decision and effects of other subordinate systems were shown to be in an advantageous condition acting as a financial source to advocates of structural reorganization privatization. On the other hand, advocates affected by the external variables share a certain belief system in which the advocates of privatization share the justification of profitability while the advocates of collectivization share the justification of publicness. In these flows, the announcement of the privatization plan of public enterprises of the committee of planning and budgeting acts as a matter of contact which opens the windows for policy changes, and this window goes through ignition, explosion, and fixation which causes fierce interactions among advocates of both sides. Eventually, in accordance with the contents of excluding electricity(KEPCO) from the list for privatization the window for policy changes has closed and things have changed to a transitional KEPCO privatization policy. Based on this, the first implication is that non-official participants such as the people, social organizations, labor unions, etc. influence policy changes more than they did before. Secondly, in the process of policy changes, there is an order of boundary even in the fierce interactions between each advocate. Thirdly, specific variables can play various roles in complex policy phenomenon. Fourthly, a logical analysis using the ACMS model is possible in Korea as well. Fifthly, as a result of analyzing the change process of the KEPCO structural reorganization privatization policy through the ACMS model, not all matched with the main research results implied by the ACMS model.