• Journal of the Society of Disaster Information
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• v.7 no.3
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• pp.171-180
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• 2011

As a great earthquake hit east Japan recently, the interests for the necessity of earthquake resistant design and earthquake resistance ability of existent structures are much increased. The damage or collapse of a bridge, as a social overhead capital structure affects socially and economically. Thus the evaluation of earthquake resistance ability of these structures is very important. The reviewing methods for earthquake resistance ability are mostly deterministic. Although the deterministic methods are fit for the evaluation of safety of each member, they are not practical for the whole structure. For the evaluation of structural safety for earthquake, the method for the evaluation of fragility or damage is needed for some stages of damage. In this paper, fragility curves of steel box bridge using RFPB bearing for PGA, PGV, SA, SV, SI are constructed, and these are compared with the cases of FPB.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.7 no.2
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• pp.107-120
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• 1987

This study is directed for the evolution of the rational approaches to the systematic evaluation of the load carrying capacity of bridges based on the practical and second moment reliability methods. A new approach for the evaluation of load carrying capacity of exsisting bridges is proposed in this study. The key idea behind this approach is in the fact that the load carrying capacity of an existing bridges under extreme traffic truck loadings may be measured by evaluating and classifying the reliability state of the bridge in terms of reliability index(${\beta}$). The rating formulas developed in this study are applied for the evaluation of load carrying capacity of the several actual deteriorated bridges inspected and tested for the capacity rating, and the results are compared with those calculated by using the current rating formulas. It may be concluded that the proposed rating formulas which is derived based on reliability methods, have to eventually replace the current rating formula when the basic statistical data for the resistance and load effects become available in the near future.

• Journal of the Society of Naval Architects of Korea
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• v.37 no.4
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• pp.92-105
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• 2000

A study for the structural strength evaluation on the slender doubler plate has been performed through the systematic evaluation process. In order to estimate the proper static strength of doubler plate subjected to the longitudinal in-plane compression, elasto-plastic large deflection analysis is introduced including the contact effect between main plate and doubler. The characteristics of stiffness and strength variation are discussed based on their results. Also, in order to compare the doubler structure with the original strength of main plate without doubler, a simple formula for the evaluation of the equivalent flat plate thickness is derived based on the additional series analysis of flat plate structure. Using this derived equation, the thickness change of a equivalent flat plate is analyzed according to the variation of various design parameters of doubler plate and some design guides are suggested in order to maintain the original strength of main plate without doubler reinforcement. Finally, correlation between derived equivalent flat plate formula and the developed buckling strength formulas by author et al. is discovered and these relations are formulated for the future development of simple strength evaluation formula of doubler plate structure.

• Journal of the Korea Fashion and Costume Design Association
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• v.20 no.4
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• pp.147-162
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• 2018

The purpose of this study is to conduct a comprehensive and objective evaluation on the effectiveness of the activation policies for the Seongsu handmade shoe industry and to suggest the direction of more effective future policies using the results. The list of the activation policies for the Seongsu handmade shoe industry was investigated and awareness, appropriateness, effectiveness, and satisfaction were measured from the representatives of the Seongsu handmade shoe companies via an off-line survey. A total of 61 usable data sets were statistically analyzed. Based on the evaluation result of the policies, a focus group interview with 6 representatives of the Seoungsu handmade shoe industry was conducted to investigate the causes and effectiveness of the policies and the problems pertaining to those policies. The awareness, effectiveness, and satisfaction of the policies were evaluated as negatives, while the appropriateness of the policies was evaluated as a positive. The manufacturers of the handmade shoes evaluated policies that improve the environment of the workplace higher and evaluated the handmade shoes education policy lower than the distributors and raw materials suppliers. The problems with the activation policies for the Seongsu handmade shoes industry were found to be structural problems, issues with the implementation of the policies, and that the fact that the policies did not reflect the reality of the industry.

• Journal of the Korean Geotechnical Society
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• v.37 no.9
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• pp.37-50
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• 2021

Recently, due to the expansion of urban infrastructure using underground spaces in urban areas, many adjacent constructions and excavations have been made carried out between existing facilities, and complaints related to the stability of existing facilities due to close construction have become significant issues. In this study, it was closely reviewed for the existing metro tunnel structure in the new Dongbuk urban metro railway to determine the behavioral characteristics of tunnel structure according to adjacent tunnel construction. Also, it was analysed the evaluation of the safety zone and excavation method for metro tunnel structure. And after a detailed damage assessment, track irregularities and structural calculation by using a numerical analysis, stability of the metro tunnel structure according to nearby tunnel excavation was evaluated to be secured for safety. This study is expected to be applied as practical reference to review the evaluation of safety effects of existing tunnel structure and buildings according to adjacent construction in complex deep urban tunnelling.

• Journal of the Earthquake Engineering Society of Korea
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• v.26 no.5
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• pp.211-217
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• 2022

New buildings have been designed using different seismic design standards that have been revised. However, the seismic performance of existing buildings is evaluated through the same performance evaluation guidelines. Existing buildings may not satisfy the performance targets suggested in the current guidelines, but there are practical limitations to discriminating the existing buildings with poor seismic performance through a full investigation. In this regard, to classify buildings with poor seismic performance according to the applied standard, this study aimed to evaluate performance-based investigation of the seismic design proposals of buildings with different design standards. The target buildings were set as RC ordinary moment frames for office occupancy. Changes in seismic design criteria by period were analyzed, and the design spectrum changes of reinforced concrete ordinary moment resisting frames were compared to analyze the seismic load acting on the building during design. The seismic design plan was derived through structural analysis of the target model, compared the member force and cross-sectional performance, and a preliminary evaluation of the seismic performance was performed to analyze the performance level through DCR. As a result of the seismic performance analysis through the derived design, the reinforced concrete ordinary moment frame design based on AIK 2000 has an insufficient seismic performance level, so buildings built before 2005 are likely to need seismic reinforcement.

• Journal of Korean Society for Quality Management
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• v.52 no.1
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• pp.23-42
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• 2024

Purpose: This study aims to investigate the impact of two types of information quality, which are platform-oriented information quality and customer-oriented information quality, on customers' decision-making processes in the Online to offline (O2O) platform environment. Grounded in the product brokering efficiency model, which encompasses screening cost, evaluation cost, and decision quality, a model framework was developed. Furthermore, this study explores how these decision-making processes affect customer loyalty. Methods: Given that food delivery apps are the most widely used O2O service in Korea, this study targeted users of these apps for data analysis. We conducted hypothesis testing through a purposive sampling methodology focusing on food delivery app users. A Partial Least Squares Structural Equation Modeling analysis was conducted to analyze the data. The data collection occurred via an online survey from October to December 2021, with a total of 212 respondents participating. Results: The results of this study revealed the significant role of information quality in helping customers' decision processes while using food delivery apps. Specifically, it was found that platform-oriented information positively influences decision quality, while customer-oriented information significantly affects both the reduction of evaluation cost and the enhancement of decision quality. Additionally, the study indicated that lower evaluation costs and higher decision quality lead to increased platform loyalty. However, a reduction in screening cost did not have a significant impact on platform loyalty. Conclusion: While previous studies have overlooked the existence of two sides, service provider and user, in a platform, this research holds significance in its analysis of how information quality impacts loyalty by utilizing the two kinds of information quality. Practitioners can enhance customer loyalty to the platform by enriching customer-oriented information, thereby reducing customers' evaluation costs and encouraging more loyal usage of the platform.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.3
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• pp.155-162
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• 2002

The cyclic amidohydrolase family enzymes, which include allantoinase, dihydroorotase, dihydropyrimidinase and (phenyl)hydantoinase, are metal-dependent hydrolases and play a crucial role in the metabolism of purine and pyrimidine in vivo. Each enzyme has been independently characterized, and thus well documented, but studies on the higher structural traits shared by members of this enzyme family are rare due to the lack of comparative study. Here, we report upon the expression in E. coli cells of maltose-binding protein (MBP)- and glutathione S-transferase (GST)-fused cyclic amidohydrolase family enzymes, facilitating also for both simple purification and high-level expression. Interestingly, the native quaternary structure of each enzyme was maintained even when fused with MBP and GST. We also found that in fusion proteins the favorable biochemical properties of family enzymes such as, their optimal pHs, specific activities and kinetic properties were conserved compared to the native enzymes. In addition, MBP-fused enzymes showed remarkable folding ability in-vitro. Our findings, therefore, suggest that a previously unrecognized trait of this family, namely the ability to functional fusion with some other protein but yet to retain innate properties, is conserved. We described here the structural and evolutionary implications of the properties in this family enzyme.

• Journal of Ocean Engineering and Technology
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• v.13 no.3 s.33
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• pp.36-48
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• 1999

Fatigue life and crack retardation behavior after penetration were experimentally examined using surface pre-cracked specimens of aluminium alloy 5083. The Wheeler model retardation parameter was used successfully to predict crack growth behavior after penetration. By using a crack propagation rule, the change in crack shape after penetration can be evaluated quantitatively. Advanced, waveform-based acoustic emission (AE) techniques have been successfully used to evaluate signal characteristics obtained form fatigue crack propagation and penetratin behavior in 6061 aluminum plate with surface crack under fatigue stress. Surface defects in the structural members are apt to be origins of fatigue crack growth, which may cause serious failure of the whole structure. The nondestructive analysis on the crack growth and penetration from these defects may, therefore, be one of the most important subjects on the reliability of the leak before break (LBB) design. The goal of the present study is to determine if different sources of the AE could be identified by characteristics of the waveforms produced from the crack growth and penetration. AE signals detected in four stages were found to have different signal per stage. With analysis of waveform and power spectrum in 6061 aluminum alloys with a surface crack, it is found to be capabilities on real-time monitoring for the crack propagation and penetration behavior of various damages and defects in structural members.

• Journal of Educational Research in Mathematics
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• v.8 no.1
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• pp.101-123
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• 1998

The purpose of this study is to construct the "open" instructional model that might be used properly in mathematics classroom. In this study, the core philosophy of "openness" in mathematics instruction is looked upon as the transference itself from pursuing simply strengthening the function of instruction such as effectiveness in the management of educational environment into the understanding of the nature of mathematics learning and the pursuing of true effectiveness in mathematics learning. It means, in other words, this study is going to accept the "openness" as functional readiness to open all the possibility among the conditions of educational environment for the purpose of realizing maximum learning effectiveness. With considering these concepts, this study regards open mathematics education as simply one section among the spectrum of mathematics education, thus could be included in the category of mathematics education. The model for open instruction in mathematics classroom, constructed in this study, has the following virtues: This model (1) suggests integrated view of open mathematics instruction that could adjust the individual and sporadic views recently constructed about open mathematics instruction; (2) could suggest structural approach for the construction of open mathematics instruction program; (3) could be used in other way as a method for evaluation open mathematics instruction program.thematics instruction program.