• Journal of Korean Society of Steel Construction
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• v.15 no.1
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• pp.41-50
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• 2003

Nondestructive Damage Evaluation (NDE) techniques yield the damage location and its size from the modal characteristics of pre-damaged and post-damaged structures. To predict the system reliability of the aging structure, results from the NDE are integrated into the element/component failure probabilities. The element/component failure probabilities can be calculated from failure functions for each element/component with the aid of techniques from a structural reliability analysis. In this paper, a method to estimate the system reliability of a structure that is based on the reliabilities of elements/components in a given structure is presented. The efficacy of the combination of the nondestructive damage detection and the structural reliability evaluation is demonstrated using pre-damaged and post-damaged modal data obtained from numerical simulations of a rigid frame.

• Journal of Korea Technology Innovation Society
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• v.10 no.3
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• pp.580-603
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• 2007

This paper examines accountability trend for government supported research institutes through the analysis of what aspects of accountability have been emphasized in the institute evaluation from 1991 to 2005. We divided research period into pre-research council period(1991-1998) and post-research council period(1999-2005). In pre-research council period, we find four kinds of accountability for government supported research institutes, that is, compliance accountability for regulation, managerial accountability, performance accountability and social accountability and great emphasis has been put on compliance accountability for regulation and managerial accountability. In post-research council period, financial accountability for soundness has been added to the above four kinds of accountability and great emphasis has been put on performance accountability and managerial accountability, especially performance accountability. The concrete contents of an accountability has been also changed between pre-research council period(1991-1998) and post-research council period(1999-2005). Regulation accountability in the pre-research council period are related to conforming to government rules for institute operation and regulation defining institute function for reformulation, but in post-research council period, it has been focused on rules for the rationalization of management. Managerial accountability has been changed from emphasizing on management efficiency approximately to focusing on more specific management efficiency like the appropriateness of personnel management, the efficiency of budget management and project management, reasonableness of evaluation and compensation. Performance accountability has been changed in methods for measuring performance, in the pre-research council period, it has been taken quantitative method for measuring productivity, but, in post-research council period, qualitative approach like objective management has been complemented. Finally, accountability for government supported research institutes has been changed towards being concrete in many sided accountabilities and focusing on performance accountability.

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.4
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• pp.235-242
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• 2005

This study is on the evaluation of performance of polymer cement mortar which is used for pre-wetting spray method. Pre-wetting spray method is an epoch-making method to repair concrete structures damaged, which is added a small quantity water preciously to dry mortar to reduce dust and rebound and spray mortar mixed with fixed quantity water at nozzle before spray. The result showed that physical performance such like compressive, flexural and adhesive strength of polymer cement mortar, TS 100 used for pre-wetting spray method was superior to other repair mortar. Also durable performance such as resistance on permeability of chloride ion, carbonation, chemical and freezing-thawing was excellent.

• KIPS Transactions on Software and Data Engineering
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• v.6 no.7
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• pp.353-360
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• 2017

In this study, a software education program based on blended learning using scratch was designed for pre-service elementary teachers' software education. Software education program was applied to experimental group and control group within the university of education using Scratch programming for 12 weeks. Blended learning using online lectures was applied to experimental group. The pre-service teachers' recognition about software education and self-evaluation of computational thinking were performed. Then, we analyzed the effect of the developed education program on the recognition of software education and computational thinking. As a result, the level of post-recognition of software education in the experimental group was significantly higher than that of the pre-recognition. In the self-evaluation of computational thinking, the experimental group was significantly higher than the control group. Therefore, it can be seen that the software education program based on blended learning can help improve the learner's computational thinking.

• Korean journal of communication and information
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• v.61
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• pp.28-51
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• 2013

The present study analyzed the effects of brand extension on the existing parent brand by applying the media brand extension model which previous studies had suggested based on consumer based brand equity model. Based on previous studies, the present study constructed a research model in which pre-brand extension parent brand evaluation, brand portfolio quality variance, perceived number of brand extensions, perceived fit between parent brand and brand extended channel, and brand extended channel evaluation are supposed to affect post-brand extension brand extension evaluation, and tested the media brand extension feedback effects model through structural equation modeling. The analysis results show that pre-brand extension parent brand evaluation, brand portfolio quality variance, perceived fit, and brand extended channel evaluation affect post-brand extension parent brand evaluation while the effect of perceived number of brand extensions is not significant.

• East Asian mathematical journal
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• v.33 no.2
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• pp.217-233
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• 2017

This study expects that Team Based Project Learning can act positive role to improve pre-service elementary teachers' teaching competence from previous studies. So designing and executing Team Based Project Learning program, I can provide some suggestions to the teaching method for teacher training education. In this study, Team Based Project Learning focuses on the use of history of mathematics in school mathematics. Also from organizing the team to evaluation, I conduct team activity systematically both inside and outside the classroom. The result of this study shows that pre-service elementary teachers' teaching competence has improved and I could identify the positive response about the value of using the history of mathematics and effect of Team Based Project Learning in mathematics learning.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.687-691
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• 2001

Al alloy matrix composite with TiNi shape memory fiber as reinforcement has been fabricated by hot pressing to investigate mechanical properties. The stress-strain behavior of the composites was evaluated at temperatures between 363K and room temperature as a function of pre-strain by using experimental and finite element analysis, and both cases showed that the tensile stress at 363K was higher than that of the room temperature. Especially, the tensile stress of this composite increases with increasing the amount of pre-strain, and it also depends on the volume fraction of fiber and heat treatment. The smartness of the composite is given due to the shape memory effect of the TiNi fiber which generates compressive residual stress in the matrix material when heated after being pre-strained.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.847-852
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• 2000

This paper presents an evaluation of the behavior and strength of two pre-tensioned concrete deep beams tested to failure with using the nonlinear strut-tie model approach. In the approach, the effective prestressing forces represented be equivalent external loads are gradually introduced along its transfer length in the nearest strut-tie model joints, the friction at the interface of main diagonal shear cracks is modeled by diagonal struts along the direction of the cracks in strut tie-model, and additional positioning of concrete ties a the place of steel ties is incorporated. Through the analysis of pre-tensioned concrete deep beams, the nonlinear strut-tie model approach proved to present effective solutions for prediction the essential aspects of the behavior and strength of pre-tensioned concrete deep beams.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.255-261
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• 2000

Tube bending is one of the conventional manufacturing process. Recently, tube bending was highlighted in automotive industry by hydroforming. Tube hydroforming process is divided into pre-bending process and hydroforming process. It's initial state is very important in die cavity of first hydroforming process. So tube bending is important factor of the hydroforming process. In this paper, two pre-bending simulations, by a rotary draw bending machine and a bend die. This paper presents the simulation results in pre-bending process that is used to form an automotive part, tie-bar.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.1197-1200
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• 2003

Urban subways usually make environmental problems because subway vibrations are transmitted to building structures. However, when the buildings are designed, vibrations due to subway are not usually considered in advance. This results in many environmental vibration problems after buildings are constructed. This study was carried out to set up and evaluate a pre-assessment technique for the environmental impact of urban subway vibration on newly planned buildings near a subway line. for this purpose, semi-emperical method was set up and vibration measurements were made on site in accordance with construction schedule. Computer simulation was also performed using ANSYS software to predict the building vibration and compared with the measured results for evaluation of the pre-assessment technique.