• Journal of Power Electronics
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• v.13 no.3
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• pp.429-436
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• 2013

Online simulations are utilized to reduce time and cost in the development and performance optimization of plug-in hybrid electric vehicle (PHEV) and electric vehicles (EV) systems. One of the most important factors in an online simulation is the accuracy of the model. In particular, a model of a battery should accurately reflect the properties of an actual battery. However, precise dynamic modeling of high-capacity battery systems, which significantly affects the performance of a PHEV, is difficult because of its nonlinear electrochemical characteristics. In this study, a dynamic model of a high-capacity battery cell for a PHEV is developed through the extraction of the equivalent impedance parameters using electrochemical impedance spectroscopy (EIS). Based on the extracted parameters, a battery cell model is implemented using MATLAB/Simulink, and charging/discharging profiles are executed for comparative verification. Based on the obtained results, the model is optimized for a high-capacity battery cell for a PHEV. The simulation results show good agreement with the experimental results, thereby validating the developed model and verifying its accuracy.

• Journal of The Korea Institute of Healthcare Architecture
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• v.16 no.2
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• pp.29-36
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• 2010

Recently, the system that can eliminate discrimination and barrier to disabled, ensure the substantial independence of disabled and help participation in community of disabled is required. Therefore, the purpose of this study is 'construction of the Barrier-free environment' which members of societies included the disabled can live safely in the daily living environment. To achieve this result, this study is shown establishment and complementary direction of the policy related convenient facilities by comparing between domestic and international policy of the convenient facilities. The results of this study are as follows; Firstly, among the conflicting part between related laws and design standards shold be constantly supplemented. Secondly, policy to promote convenient in residential part is needed. Thirdly, composition of the organization that can support professional housing reconstruction is required. Fourthly, from early stage of policy making, not only opinion reflection of users but also maintenance of convenient facilities, continuous maintenance plan and making a policy for verification system is needed. Finally, when the revision of the existing policies or new policies undergo, 'Barrier-free perspective' should be considered.

• Land and Housing Review
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• v.2 no.4
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• pp.325-344
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• 2011

On November 1, 2010, the release of ISO 26000 was announced. ISO 26000 does not require 3rd party verification. But even though it is a standard that is voluntarily adopted, because the international standard for social responsibility can be applied as a trade barrier or business condition between countries, it cannot be ignored. So it is clear that we need to be alerted and prepared for this. This paper offers to help with such needs through organizations by developing an index that organizations can use to understand their current situation and diagnose themselves. This paper conducts a comparative analysis between the 7 core subjects and issues of ISO 26000, the existing indexes used by national institutions and the guideline for sustainable management report, the GRI, with the goal of developing a self-diagnostic index that organizations can utilize in order to diagnose their level of social responsibility. It is divided into the 7 core subjects with 181 measurement issues. There are 7 quantitative issues and 164 qualitative issues. The core subjects, excluding governance, are each alloted 14 points, while governance is alloted with 16 points, for a total score of 100 points. This paper is significant in that it is the first index to make self-diagnostic possible.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.8
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• pp.596-600
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• 2009

To support an efficient management of software verification and validation activities, many defect prediction models have been proposed based on object oriented metrics. They usually adopt logistic regression analysis, And, they state that the correctness of prediction is about 60${\sim}$70%, We performed a similar experiment with Eclipse 3.3 to check their prediction effectiveness, However, the result shows that correctness is about 40% which is much lower than the original results. We also found that univariate logistic regression analysis produces better results than multivariate logistic regression analysis.

• Smart Structures and Systems
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• v.18 no.3
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• pp.585-599
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• 2016

Steel cables serve as the key structural components in long-span bridges, and the force state of the steel cable is deemed to be one of the most important determinant factors representing the safety condition of bridge structures. The disadvantages of traditional cable force measurement methods have been envisaged and development of an effective alternative is still desired. In the last decade, the vision-based sensing technology has been rapidly developed and broadly applied in the field of structural health monitoring (SHM). With the aid of vision-based multi-point structural displacement measurement method, monitoring of the tensile force of the steel cable can be realized. In this paper, a novel cable force monitoring system integrated with a multi-point pattern matching algorithm is developed. The feasibility and accuracy of the developed vision-based force monitoring system has been validated by conducting the uniaxial tensile tests of steel bars, steel wire ropes, and parallel strand cables on a universal testing machine (UTM) as well as a series of moving loading experiments on a scale arch bridge model. The comparative study of the experimental outcomes indicates that the results obtained by the vision-based system are consistent with those measured by the traditional method for cable force measurement.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.10
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• pp.95-101
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• 2021

An analysis was conducted to predict the behavior of gasket by applying an optimal-strain energy-density function selected through a uniaxial tensile test and an analysis of the gasket used in an actual hydrogen fuel cell. Among the models compared to predict the materials' properties, the Mooney-Rivlin secondary model showed the behavior most similar to the test results. The maximum stress of the gasket was not significantly different, depending on the location. The maximum surface pressure of the gasket was higher at positions "T" and "Y" than at other positions, owing to the branch-shape effect. In the future, a jig that can measure the surface pressure will be manufactured and a comparative verification study will be conducted between the test results and the analysis results.

• The Journal of Advanced Prosthodontics
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• v.11 no.5
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• pp.271-279
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• 2019

PURPOSE. The newest technologies for digital implant impression (DII) taking are developing rapidly and showing acceptable clinical results. However, scientific literature is lacking data from clinical studies about the accuracy of DII. The aim of this study was to compare digital and conventional dental implant impressions (CII) in a clinical environment. MATERIALS AND METHODS. Twenty-four fixed zirconia restorations supported by 2 implants were fabricated using conventional open-tray impression technique with splinted transfers (CII group) and scan with Trios 3 IOS (3Shape) (DII group). After multiple verification procedures, master models were scanned using laboratory scanner D800 (3Shape). 3D models from conventional and digital workflow were imported to reverse engineering software and superimposed with high resolution 3D CAD models of scan bodies. Distance between center points, angulation, rotation, vertical shift, and surface mismatch of the scan bodies were measured and compared between conventional and digital impressions. RESULTS. Statistically significant differences were found for: a) inter-implant distance, b) rotation, c) vertical shift, and d) surface mismatch differences, comparing DII and CII groups for mesial and distal implant scan bodies ($P{\leq}.05$). CONCLUSION. Recorded linear differences between digital and conventional impressions were of limited clinical significance with two implant-supported restorations.

• Korean Journal of Childcare and Education
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• v.16 no.6
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• pp.155-183
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• 2020

Objective: In this study, we tried to verify the effects of program by constructing an effective maker education program that can cultivate the maker's capabilities through voluntary production activities by utilizing various technologies and tools. Methods: First, prior research on maker education and the station teaching strategy was considered, and interviews and surveys were conducted on prospective early childhood teachers in order to find out the degree of demand for maker education. The final program was finalized through verification of the contents validity. Results: The developed program was applied to a total of 49 prospective early childhood teachers (24 in the experimental group, 25 in the comparative group) attending U College, and it was found to be effective in enhancing convergence talent, education knowledge of early childhood teachers' technology, and self-directed learning skills. Conclusion/Implications: These findings show that the preliminary early childhood teacher maker education program using station teaching strategy has educational value that can be used as an effective teaching method in early childhood education.

• The Journal of Economics, Marketing and Management
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• v.10 no.6
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• pp.47-57
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• 2022

Purpose: This study explored the relationship between product characteristics and customer purchase intention in cross-border online shopping. Research design, data, and methodology: Through literature review, the research model of product characteristics and consumers' purchase intention is constructed, and trust is taken as a medium variable. Based on the survey data of Chinese consumers, empirical analysis and hypothesis verification are conducted. This study used SPSS version 21 to confirm the reliability and validity of the research model. To confirm the media effect of the model in this study, the Sobel Test was used. Results: The results of hypothesis identification of this research model showed that 8 of the 11 hypotheses were adopted and 3 were rejected. Results confirmed the relationship between product characteristics (specification, diversity, reputation, novelty, quality) and customer purchase intention. Conclusions: The result from this study had particular theoretical significance for improving the research on cross-border online shopping systems to improve the safety and satisfaction of customers in cross-border online shopping.

• Journal of Positioning, Navigation, and Timing
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• v.10 no.1
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• pp.55-66
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• 2021

In this paper, we propose a signal propagation modeling technique for generating a positioning fingerprint DB based on Long Term Evolution (LTE) signals. When a DB is created based on the location-based signal information collected in an urban area, gaps in the DB due to uncollected areas occur. The spatial interpolation method for filling the gaps has limitations. In addition, the existing gap filling technique through signal propagation modeling does not reflect the signal attenuation characteristics according to directions occurring in urban areas by considering only the signal attenuation characteristics according to distance. To solve this problem, this paper proposes a Deep Neural Network (DNN)-based signal propagation functionalization technique that considers distance and direction together. To verify the performance of this technique, an experiment was conducted in Seocho-gu, Seoul. Based on the acquired signals, signal propagation characteristics were modeled for each method, and Root Mean Squared Errors (RMSE) was calculated using the verification data to perform comparative analysis. As a result, it was shown that the proposed technique is improved by about 4.284 dBm compared to the existing signal propagation model. Through this, it can be confirmed that the DNN-based signal propagation model proposed in this paper is excellent in performance, and it is expected that the positioning performance will be improved based on the fingerprint DB generated through it.