• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6A
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• pp.965-976
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• 2006

A realistic lifetime seismic-reliability based approach is unavoidable to perform Life-Cycle Cost (LCC)-effective optimum design, maintenance, and retrofitting of structures against seismic risk. So far, though a number of researchers have proposed the LCC-based seismic design and retrofitting methodologies, most researchers have only focused on the methodological point. Accordingly, in most works, they have not been quantitatively considered critical factors such as the effects of seismic retrofit, maintenance, and environmental stressors on lifetime seismic reliability assessment of deteriorating structures. Thus, in this study, a systemic lifetime seismic reliability analysis methodology is proposed and a program HPYER-DRAIN2DX-DS is developed to perform the desired lifetime seismic reliability analysis. To demonstrate the applicability of the program, it is applied to an example bridge with or without seismic retrofit and maintenance strategies. From the numerical investigation, it may be positively stated that HYPER-DRAIN2DX-DS can be utilized as a useful numerical tool for LCC-effective optimum seismic design, maintenance, and retrofitting of bridges.

• Structural Engineering and Mechanics
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• v.14 no.3
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• pp.287-306
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• 2002

The assessment of structural performance of transfer structures under potential seismic actions is presented. Various seismic assessment methodologies are used, with particular emphasis on the accurate modelling of the higher mode effects and the potential development of a soft storey effect in the mega-columns below the transfer plate (TP) level. Those methods include response spectrum analysis (RSA), manual calculation, pushover analysis (POA) and equivalent static load analysis (ESA). The capabilities and limitations of each method are highlighted. The paper aims, firstly, to determine the appropriate seismic assessment methodology for transfer structures using these different approaches, all of which can be undertaken with the resources generally available in a design office. Secondly, the paper highlights and discusses factors influencing the response behaviour of transfer structures, and finally provides a general indication of their seismic vulnerability. The representative Hong Kong building considered in this paper utilises a structural system with coupled shear walls and moment resisting portal-frames, above and below the TP, respectively. By adopting the wind load profile stipulated in the Code of Practice on Wind Effects: Hong Kong-1983, all the structural members are sized and detailed according to the British Standards BS8110 and the current local practices. The seismic displacement demand for the structure, when built on either rock or deep soil sites, was determined in a companion paper. The lateral load-displacement characteristic of the building, determined herein from manual calculation, has indicated that the poor ductility (brittle nature) of the mega-columns, due mainly to the high level of axial pre-compression as found from the analysis, cannot be effectively alleviated solely by increasing the quantity of confinement stirrups. The interstorey drift demands at lower and upper zones caused by seismic actions are found to be substantially higher than those arising from wind loads. The mega-columns supporting the TP and the coupling beams at higher zones are identified to be the most vulnerable components under seismic actions.

• Journal of Digital Contents Society
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• v.19 no.6
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• pp.1131-1144
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• 2018

The Purpose of this study is to propose 4F Process, which is one of the development methodology of the gamification. For the effectiveness analysis of the 4F Process, game and gamification related theories are applied and conducted comparative analysis with the published gamification development methodology. This studies results show that the 4F Process is a relatively high level of perfection of gamification development methodology than eight of published methodologies by found out this study team. But, there was a complementary point in the 4F Process. Based on results of this study, this study mentioned the pros and coms of the 4F Process and suggested the step-by-step guideline as a necessary element for the gamification development methodology.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.5 no.1 s.9
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• pp.21-30
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• 2006

For urban highway network, traffic control strategy paradigm has been shifted from the private auto-oriented to the public transit-oriented. Introduction of exclusive median bus lanes (EMBL) in Seoul, Korea, has especially accelerated such changes in transportation policy and thus highway environment. Left-turning movement treatment at signalized intersections where EMBL pass through has been emerged as one of the rising problems associated with a current signal head with 4-signal lens, the Korea standard. This study proposes a new signal phase operation scheme for signal operation at an isolated intersection where EMBL pass through. The authors propose to use of an exclusive bus signal head indicating right-of-way of transits on EMBL only. Based on it, three different phase operation scheme were developed for left-turn treatments for traffic control with (1) traffic responsive control mode and (2) time-of-day traffic control mode. In addition, methodologies to design and develop signal maps for the proposed signal phase schemes are also developed. The proposed operation can only be possible when additional uses of signal state relay boards are allowed.

• Fire Science and Engineering
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• v.31 no.3
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• pp.137-143
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• 2017

A sufficient number of ambulances are critical for preventing delayed vehicle dispatch for emergency patients. This study presents effective methodologies for evaluating the effects of ambulance quantities on availability. The statistical properties of the emergency requests and responses were analyzed for a city in Korea. The inter-request times were modeled by statistical distributions. The ambulance dispatch was modeled using simulation, reflecting the shared dispatch among the city districts. The simulation results revealed that the existing ambulance quantity could successfully meet the majority of the requests, but more vehicles were desirable for improvement. The locations of the additional vehicles were determined efficiently by simulations with a greedy approach. The simulations with added vehicles showed a significantly better coverage of the emergency calls. This research can help design improved emergency vehicle operations, and help save lives.

• Journal of the Korean Institute of Intelligent Systems
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• v.12 no.4
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• pp.311-316
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• 2002

Difficulties of the level control in the steam generator are increased due to their nonlinear characteristics. Futhermore, parameter uncertainties of the steam generator is related with control performance and stability. The efficiency of digital conversion in control systems is proved in many recent researches. In order to solve this problem, this paper suggests robust digital fuzzy controller design methodologies of the steam generator which have unstable parameters. Takagi-Sugeno (TS) fuzzy model is used to construct a fuzzy model which has uncertainties in the steam generator. In designing procedure, intelligent digital redesign method is used to control the nonlinear system. This digital controller keeps the performance of the analog controller. Simulation examples are included for ensuring the proposed control method.

• Journal of The Korean Association of Information Education
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• v.5 no.1
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• pp.49-64
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• 2001

Thanks to the technological developments in the Internet, the Web-Based Instruction in the school practices has been available which is now taking its place as one of the new educational methods. With the increased interest in Web-Based Instruction, there appear a lot of materials and methodologies on utilizing the WEB to actively discuss and deal with the teaching-learning ways. Nevertheless, they comparatively tend to overlook the aspect of school guidance such as the development of sociability through social interaction which is an important element for building the personality of learner. This study has tried to design and apply the teaching-learning system for the promotion of social interaction in the Web-Based Instruction, and also made an investigation into the influences of social interaction on the development of children's sociability in the WEB field.

• Journal of The Korean Association of Information Education
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• v.19 no.2
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• pp.243-252
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• 2015

The software education to elementary students will be conducted from 2019. One of highlights of software education is a programming experience. It requires a higher level of programming education to students that are interested in programming. This problem can be solved by the club activities. But the materials for programming education for elementary students is not much. Therefore, we developed a programming material for club activities of the elementary school. We did not develop it as a programming manual. The students can understand a problem, can design through decomposition and abstraction processes, and can write a program when they are learning with this material. As a result, we expect that they can enhance their computational thinking abilities. We proved that our material is suitable for elementary students through a demonstration class. Therefore, we expect that our development methodologies for the material for programming education will contribute to develop a material for programming education.

• Journal of Korean Academy of Nursing
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• v.37 no.6
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• pp.1013-1019
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• 2007

Purpose: This study was to determine the current trend of nursing research as exploring both quantitative and qualitative methodologies, and to provide the explicit direction to improve the quality of published papers. Methods: Total of 366 articles published between 2004 and 2006 was reviewed using the criteria of analysis. Results: There was more number of quantitative studies than qualitative studies. More studies were conducted with subjects who had health problems, and studies that targeted women and elderly population have been significantly increased. In quantitative methodology, utilization of experimental and quasi-experimental designs has been increased, however descriptive study was dominant as yet. In qualitative methodology, studies using grounded theory and phenomenology were frequently published. It was noted that theoretical framework and rational for sample size were rarely presented in quantitative study. Philosophical position and the process of preparation for study, which guided the research, were not clearly described in qualitative study. Conclusion: The findings of this review suggest that published studies have been improved and diversified, however, detailed and clear evaluation tool that assesses study process and method should be developed as a way to further improve the quality of published papers.

• Journal of the Korea Furniture Society
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• v.21 no.1
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• pp.26-39
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• 2010

This is a leading study to replace the structural analysis methodology on the specific traditional joint by a numerical analysis. Tests were carried out to test the compressive methodologies with the numerical results. The Japanese larch was used as a sample. The Orthotropic property of wood was specifically considered for the finite element numerical analysis. Linear numerical analysis and non-linear numerical analysis for the BEAM element and the two SOLID elements of ANSYS were used to analyze the compressive performance. In addition, more finely divided elements were used to raise the accuracy of the numerical result. Finally, the statistically significant differences were tested between that of the analytical and numerical results. It could be concluded that the SOLID 64 element shows the most optimum result when the non-linear analysis with the more finely divided element was used. However, finely dividing of the element is a considerable time consuming process, and it is quite difficult to raise the accuracy of the non-linear numerical analysis. Therefore, if considering the vertical displacement to be of the only interest, the BEAM element is more efficient than the SOLID element because the BEAM element is reflected as a simple line, which is less time consuming and difficult in dividing the elements. But, the BEAM element cannot accurately model the knot as a strength defect factor which is an important property in the orthotropic property of wood. Therefore, the SOLID element should be used to model the strength defect factor, knot, as it can be efficiently applied on the structural size flexure member which could be more strongly effected by the knot. In addition, it is useful at times when the failure types of members are to be more closely investigated, as the SOLID element is able to examine the local stress distribution of the member. The conclusion drawn by this study is of the good concordance between analytical results and numerical results of compressive wood members, but how orthotropic properties should only be considered. The numerical analysis on the specific Korean traditional joints will be based on the current study results.