• Journal of Advanced Navigation Technology
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• v.25 no.5
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• pp.390-396
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• 2021

In this research, design and fabrication of marine repeater capable to extend communication coverage in monitoring system of fishing gear automatic identification, which is one of implementation method of the real-name electric fishing gear system declared by Ministry of Oceans and Fisheries in 2016, is reported. The proposed marine repeater is fabricated in a form of RF repeater with interference cancellation system (ICS), which can cancel the oscillation due to feedback signal between service antenna and link antenna. In design process, we secure the isolation of 30 dB between service antenna and link antenna. It is confirmed that when the level of feedback signal into repeater input be lower of 15 dB than repeater gain, error vector magnitude due to oscillation can be lower than the performance criterion of 6%, from the test verification. It is expected that the service coverage will be extended by applying the developed marine ICS RF repeater into marine IoT network including monitoring system of fishing gear automatic identification.

• Journal of Fashion Business
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• v.25 no.3
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• pp.51-70
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• 2021

The study aims to evaluate changes in textiles for automotive interior and suggest directions that the textile-development should take in order to achieve sustainability, and enter a circular economy system in the future. The main content and results of the study are as follows: First, we cover the overall sustainability study in the fashion and textile fields; in particular, the certification system is well established through the provision of information on the whereabouts of products to consumers and verification by external environmental auditors. Second, we considered the criteria of C2C in order to derive the necessary criteria for sustainability certification in the field of textiles. Third, we looked at the latest development trends of textile materials for automobile interiors which were divided into three categories: natural originated materials, circular economic consideration materials, and functional supplementary lightweight materials. In addition, we identified to what extent the trend of changes aggregated in the examples was satisfied and what was lacking when applied to the Basic criterion of C2C. As such, this study links and applies the sustainability criteria pursued in the fashion and textile fields to the textile for automotive interior materials, suggesting a direction for the textile field for automotive internal materials in the future. Based on the results of this study, it is hoped that studies on textiles for automotive interior considering the net economy will continue, and practical development in the industry will be realized.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.1
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• pp.63-69
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• 2019

The relative position of the orbital eye can be a criterion for evaluating several pathological conditions. It is especially useful to diagnose orbital fractures, thyroid eye disease, orbital tumors and to evaluate the outcome of medication and surgical treatment. Hertel and Naugle are representative measurement tools used to measure eyeball protrusion values, and have different measurement results, such as fixed orbits, every time they are inspected, even if the same inspector repeatedly measures them. Even with the same calibrator, it is inevitable that different manufacturers will change the design of the stationary part of the orbit, causing the surveyor to make a measurement error. In this paper, we designed and fabricated a protrusion measuring device using a white light interferometer and measured the protrusion of the human eye and found that the precision and repeatability were significantly higher than the manual measurement method.

• Journal of Ocean Engineering and Technology
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• v.36 no.2
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• pp.101-107
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• 2022

Dean (1965) proposed the use of the root mean square error (RMSE) in the dynamic free surface boundary condition (DFSBC) and kinematic free-surface boundary condition (KFSBC) as an error evaluation criterion for wave theories. There are well known wave theories with RMSE more than 1%, such as Airy theory, Stokes theory, Dean's stream function theory, Fenton's theory, and trochodial theory for deep-water waves. However, none of them can be applied for deep-water breaking waves. The purpose of this study is to provide a closed-form solution for deep-water waves with RMSE less than 1% even for breaking waves. This study is based on a previous study (Shin, 2016), and all flow fields were simplified for deep-water waves. For a closed-form solution, all Fourier series coefficients and all related parameters are presented with Newton's polynomials, which were determined by curve fitting data (Shin, 2016). For verification, a wave in Miche's limit was calculated, and, the profiles, velocities, and the accelerations were compared with those of 5^th-order Stokes theory. The results give greater velocities and acceleration than 5^th-order Stokes theory, and the wavelength depends on the wave height. The results satisfy the Laplace equation, bottom boundary condition (BBC), and KFSBC, while Stokes theory satisfies only the Laplace equation and BBC. RMSE in DFSBC less than 7.25×10^-2% was obtained. The series order of the proposed method is three, but the series order of 5^th-order Stokes theory is five. Nevertheless, this study provides less RMSE than 5^th-order Stokes theory. As a result, the method is suitable for offshore structural design.

• The Journal of Sustainable Design and Educational Environment Research
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• v.21 no.4
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• pp.13-20
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• 2022

The proportion of old buildings over 40 years among all school facilities is about 20%. The degree of deterioration is also increasing, resulting in safety risks that reduce the residential safety of faculty and students or a poor environment that does not meet the new curriculum and educational conditions is rapidly increasing the need for repair and renovation of school facilities. In order to fully fulfill its role as a space for implementing education, school architecture requires an understanding of the national curriculum and a clear criterion for determining the relationship between education and space. In order to set the evaluation criteria for deteriorated school architecture, this study presents judgment data centered on quantification and accuracy so that relevant personnel can utilize scientific analysis, research and development of detailed and systematic comprehensive evaluation indicators, and quantified evaluation methods.

• Journal of the Korean Geotechnical Society
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• v.23 no.8
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• pp.47-57
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• 2007

In this study, the analysis of density characteristics of some dredged and reclaimed ground sites, which is necessary for liquefaction evaluation of a dredged and reclaimed ground, was conducted. From analyzing a simplified liquefaction potential evaluation using SPT-N values which have been applied as domestic earthquake-resistant design criterion, improvement scheme is suggested. Based on the analysis result of density characteristics, it was found out that the relative density and the intial N-value ranged respectively $40{\sim}50%\;and\;5{\sim}8$. In the case of applying Liao & Whitman's equation to correct effective overburden pressure, liquefaction resistance of the upper ground that is relatively weaker than that of lower ground is overestimated. So, Skempton's equation is recommended. And the N value with depth which is applied for design process should be estimated by the exponential equation, $N=1.35{\sigma}'^{0.75}$.

• Composites Research
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• v.21 no.5
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• pp.1-8
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• 2008

In recent years, the reversed L-shaped perforated shear connector has been developed to mitigate the problem associated with headed stud and Perforbond shear connector and to simulate the simultaneous failure of concrete and shear connector. And FRP perforated shear connector has been applied to composite concrete and FRP module in the FRP-concrete composite bridge deck. The design criterion of the reversed L-shaped and FRP perforated shear connector has not been established yet since the lack of experimental and analytical study results. In this paper, the existing design equations for the Perforated were briefly discussed and the equation fur the prediction of shear resisting capacity of the reversed L-shaped and FRP perforated shear connector was suggested based on the experimental test, FEM analysis. and the existing equation for the Perfobond. The predict results obtained by the suggested equation arc compared with the experimental results, the applicability and effectiveness of suggested equation was verified.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.2D
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• pp.265-273
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• 2006

On the occasion of high price oil generation, we have to promote activation policy for public transportation and hold back to use passenger car, it is very important to improve of sidewalk environment for pedestrian. Evaluation for sidewalk environment will be fixed with sensibility to feel pedestrian. So, study for sensibility about comfort etc. to feel pedestrian will be carried out. In this paper, researchers interests in engineering methods to make material considering sensibility and image of human. Therefore, we carried out recognition experiment for sidewalk environment with Kansei engineering, and made a quantitativedata of sensibility adjective that it was surveyed by semantic deferential method. After grasp factors by principal analysis, we found factor effect to design criterion and sidewalk environment preference. So, we could identify a design factor for comfort environment.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5C
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• pp.343-350
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• 2006

The resistance bias factors for driven steel pipe piles are evaluated as a part of study to develop the LRFD(Load and Resistance Factor Design) for foundation structures in Korea. The 43 data sets of static load tests and soil property tests performed in the whole domestic area were collected and analyzed to determine the representative bearing capacities of the piles using various methods. Based on the statistical analysis of the data, the Davisson's criterion is proved to be the most reasonable method for estimation of pile bearing capacity among the methods used. The static bearing capacity formulas and the Meyerhof method using N values are applied to calculate the design bearing capacity of the piles. The resistance bias factors of the driven steel pipe piles are evaluated respectively as 0.98 and 1.46 by comparison of the bearing capacities for both of the static bearing capacity formulas and the Meyerhof method. It is also shown that uncertainty of the static bearing capacity formulas is relatively less than that of the Meyerhof method.

• International conference on construction engineering and project management
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• 2020.12a
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• pp.333-342
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• 2020

Due to the enhancing environmental concerns worldwide with the need of increasing demand for sustainability of building design, maintenance and operation, key stakeholders including the government and developers in many countries strike for the benefits in implementing the green design and building concepts in constructing, infrastructure as well as the buildings. Different countries have their standards or certifications for green buildings while the adoption rate of BEAM-Plus in HK is relatively less compared with other developed countries such as Europe, USA and Japan. Therefore, in the present research, BEAM-Plus, the beginning assessment method of green standard implemented in HK, will be mainly discussed. Current situation of BEAM-Plus implementation in HK will be reviewed and then adopt a systematic approach via literature review and research paper, questionnaire with Analytic Hierarchy Process (AHP) method to depict the opportunities and challenges from the perspective of government and developers regarding implementing BEAM-Plus in HK and thus investigate the implementation gaps. It is found that for both the macro level of opportunity and challenge, the most important criterion is political, in which the weighting value are 0.3114 and 0.2321 respectively. It is obvious that government plays a critical and significant role in affecting the development of BEAM plus. Technological difficulty is also an important factor that challenging and hindering the implementation of BEAM plus, the weighting value is 0.2194 under challenge hierarchy. More experts and professionals should be imported to Hong Kong to enhance the technique is building green buildings. At the end of this paper, solutions and actions will also be suggested and concluded in alleviating the challenges. Finally, solutions and actions are suggested and concluded in alleviating the challenges. Findings from this research can guide developers to consider adopting green elements, government and Green Building Council in HK to review green buildings' policy.