• Computers and Concrete
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• v.21 no.4
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• pp.355-365
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• 2018

Five previously-tested reinforced concrete frames were modelled using a nonlinear finite element analysis procedure to demonstrate the accurate response simulations for seismically-deficient frames through pushover analyses. The load capacities, story drifts, and failure modes were simulated. This procedure accounts for the effects of shear failures and the shear-axial force interaction, and thus is suitable for modeling seismically-deficient frames. It is demonstrated that a comprehensive analysis method with a capability of simulating material constitutive response and significant second-order mechanisms is essential in achieving a satisfactory response simulation. It is further shown that such analysis methods are invaluable in determining the expected seismic response, safety, and failure mode of the frame structures for a performance-based seismic evaluation. In addition, a new computer program was developed to aid researchers and engineers in the direct displacement-based seismic design process by assessing whether a frame structure meets the code-based performance requirements by analyzing the analysis results. As such, the proposed procedure facilitates the performance-based design of new buildings as well as the numerical assessment and retrofit design of existing buildings. A sample frame analysis was presented to demonstrate the application and verification of the approach.

• Korean Journal of Computational Design and Engineering
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• v.21 no.3
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• pp.234-241
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• 2016

Conventional bent plate used in mandibular reconstruction surgery needs safety verification since its mechanical properties are changed due to the plastic deformation during the bending process. In this study we investigate stability of the plastically deformed plate and the plate with the same shape without plastic deformation through the finite element analysis(FEA). First we simulate the process of plate bending to fit the defect in patient. Then, the other plate is modelled to represent a customized plate with the same shape of the plastically deformed one, but without any residual stresses from plastic deformation. After binding these plates to the mandible, we conduct the masticatory simulation. Finally, we compare the resulting Von Mises stress of the customized plate and of the bent plate. The bent plate shows much higher stress than the customized one due to the residual stresses form the bending process. The study shows that plastic deformation in the plate may decrease the safety of the reconstruction surgery.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.1113-1124
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• 2009

The limit equilibrium method and finite element method have been commonly used to assess the stability of anchored slope. However, the existing limit equilibrium methods do not consider the load transfer of anchor and, if the potential failure surface crosses the bonded zone of anchors, the anchor loads are not included in computing the factor of safety. In this paper, simplified bishop method, one among several methods based on the limit equilibrium is used to develope the Excel Sheet program and the working load of anchor along the failure surface is calculated by Flamant's formula, proposed by Morlier and Tenier(1982). Additionally, the finite element analysis of anchored slope considering the load transfer is performed in order to compare with the result from the limit equilibrium analysis and analyze the reinforced effect of anchor. From this study, new modelling method that limits the reinforcing range and considers the load transfer is proposed and Excel Sheet program is developed. The factor of safety for several cases between PC STABL and Excel Sheet program is also compared for verification of the program.

• Journal of the Korea Safety Management & Science
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• v.17 no.4
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• pp.321-333
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• 2015

This study empirically analyzed the influence of media on a visitor's satisfaction and re-visit by setting up 5 sorts of exhibition media as text, docent, virtual museum, website and Smartphone App based on practical exchange and communication between a visitor and an exhibition provider. The research results are as follows: First, all these 5 sorts of media suggested by this study were found to be able to have an influence on a visitor's satisfaction and re-visit. Second, it was found that the factors preferentially affecting a visitor's satisfaction and re-visit were 'Docent' and 'Website' factors. Accordingly, it is judged that it's necessary to more preferentially consider 'Docent' and 'Website' factors than the other factors in order to increase a visitor's satisfaction and re-visit. Third, it's possible to interpret that the bigger a visitor's satisfaction, the higher a visitor's intention to re-visit through the verification that a visitor's satisfaction will have a significant influence on a visitor's re-visit. The implication of this study lies in the fact that this study attempted at an integrated approach by analyzing the relative size of the influence through across-the-board suggestion of influential factors on a museum visitor's satisfaction and re-visit.

• Journal of Environmental Science International
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• v.16 no.7
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• pp.847-853
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• 2007

In Korean coastal areas, land reclamations are main development projects that should be based on environmental impact assessment(EIA), because those human interventions can change coastlines, damage tidal flats, and pollute adjacent areas to threat seafood safety and devaluate overall ecosystem service value. Existing procedures of the EIA for land reclamation projects were diagnosed and evaluated to enhance them. Problems were identified in the designation of survey areas, the consistency in survey sites and periods, the standardization of survey methods and reports, the confidence of survey results and the verification of predictions. Lack of integration was noticeable and could be improved by synthesizing different assessments from topography geography, marine physics, marine chemistry and marine biology. We suggest that successful precautionary marine environment management requires readjusting the cost of EIA, recruiting experts in marine environment, constructing database and establishing specialized assessment system.

• Journal of the Korea Safety Management & Science
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• v.8 no.3
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• pp.189-199
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• 2006

The purpose of this study is to analyse the job-satisfaction of police officer. The subjects of this study are selected by convenience sampling of random sampling method. The population is male and female incumbent police officers in Seoul and Gyeonggi province. The 347 cases are used to analyse the job-satisfaction among 400 police officers who answer the question. The Jod-Satisfaction Survey(Choi, 2001) are used for collecting data. In consequence of and 4 sub-factors(job-satisfaction) are found. Cronbach's alpha coefficient revealed $.058{\sim}.804,\;.846{\sim}.871$, respectively. For the statistical analysis, SPSS version 12.0 are utilized. The verification of research hypothesis are conducted by T-test, ANOVA, correlation, and multiple-regression. The significance level of all tests are set at .05. The findings of this study can be summarized as follows: Based on the demographic factors, the differences in life-style among police officers are identified. There is significant differences in gender and ages on individualism and accomplishment, in marital status on individualism and fashion-pursuing, and in income level on fashion-pursuing and accomplishment. There is also significant differences in education, religion, position and service period on accomplishment, individualism and fashion-pursuing.

• Nuclear Engineering and Technology
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• v.48 no.1
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• pp.144-152
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• 2016

Human capabilities, such as technical/nontechnical skills, have begun to be recognized as crucial factors for nuclear safety. One of the most common ways to improve human capabilities in general is training. The nuclear industry has constantly developed and used training as a tool to increase plant efficiency and safety. An integrated training framework was suggested for one of those efforts, especially during simulation training sessions of nuclear power plant operation teams. The developed training evaluation methods are based on measuring the levels of situation awareness of teams in terms of the level of shared confidence and consensus as well as the accuracy of team situation awareness. Verification of the developed methods was conducted by analyzing the training data of real nuclear power plant operation teams. The teams that achieved higher level of shared confidence showed better performance in solving problem situations when coupled with high consensus index values. The accuracy of nuclear power plant operation teams' situation awareness was approximately the same or showed a similar trend as that of senior reactor operators' situation awareness calculated by a situation awareness accuracy index (SAAI). Teams that had higher SAAI values performed better and faster than those that had lower SAAI values.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.05a
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• pp.30-31
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• 2018

The localization performance in the ship environment is degraded by RF interference due to steel structure characteristics and NLOS environment. In this paper, a wireless hybrid localization system using ZigBee, UWB, and LF technologies is proposed to improve position estimation accuracy in the ship environment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.2
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• pp.371-378
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• 2004

As an agent is applied into various fields, it is suggested as the paradigm of new application technology in the area of computer communication. However, the mobile agent brines the problem of security on an agent due to mobility. This study proposals the mobile agent protection protocol framework for more effective protection and safety. The designed Framework of protocol uses the public ky, the private key and the digital signature in PKI environment based on JAVA. This is the mechanism accomplishing safely the work of an agent by tracking the pattern of execution and the mobility plan through the VS(verification server). This also secures the suity and the flawlessness of an agent through the VS guaranteeing safety from malicious attacks.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.2
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• pp.205-213
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• 1987

A linear thermoviscoelastic material model, whose basis is on incremental constitutive equation that takes complete strain and temperature histories into account, is derived and computerized in the finite element code. The thermoviscoelastic F.E.M. code which is intended primarily to analyze the cylinder model during the cool-down period, embodies the assumption of linearly elastic bulk and visco-elastic shear responses, thermo-rheologically simple response to temperature change and isotropic thermal expansion. The verification of computer program is accomplished by first testing it against a closed form solution of A.M. Freudenthal & M. Shinozuka's. The stress and strain analyses of five cylindrical models are presented and compared with experimental results. Analytical results are good agreement with experimental results. Margins of safety are evaluated and its allowable ranges are presented.