• Nuclear Engineering and Technology
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• v.53 no.4
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• pp.1079-1087
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• 2021

NTP-ERSN is a package developed for solving the multigroup form of the discrete ordinates, characteristics and collision probability of the Boltzmann transport equation in one-dimensional cartesian geometry, by combining pin cells. In this work, C5G7 MOX benchmark is used to verify the accuracy and efficiency of NTP-ERSN package, by treating reactor core problems without spatial homogenization. This benchmark requires solutions in the form of normalized pin powers as well as the vectors and the eigenvalue. All NTP-ERSN simulations are carried out with appropriate spatial and angular approximations. A good agreement between NTP-ERSN results with those obtained with OpenMC calculation code for seven energy groups. In addition, our studies about angular and mesh refinements are carried out to produce better quality solution. Moreover, NTP-ERSN GUI has also been updated and adapted to python 3 programming language.

• Fashion & Textile Research Journal
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• v.24 no.5
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• pp.519-529
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• 2022

This research analyzed the characteristics of Hanfu street snaps in the Chinese version of TikTok to determine the development and meaning of Hanfu. Based on grounded theory, this study selected 102 representative cases by sorting Hanfu street snaps on TikTok according to popularity. Subsequently, through open coding, the cases were organized and summarized into five main categories. The findings are as follows: 1) The national cultural pride has enabled a greater number of Hanfu fans and groups to upload short videos promoting the Hanfu movement on TikTok to expand the influence of the activities and popularize cultural knowledge. 2) The users attempted cross-cultural communication by participating in cultural festivals in Western countries wearing Hanfu. 3) The 'See now buy now' function of TikTok enables numerous Hanfu merchants to upload short videos about Hanfu products to promote their products and boost sales. 4) As 'gamification' affects everyday life, computer game enthusiasts among them wear Hanfu in the form of role-playing. 5)As a unique "meme" phenomenon on TikTok, wearing Hanfu to make interesting videos has also become a form of entertainment. Thus, although the characteristics of Hanfu street snaps on TikTok originated from the transmission of Hanfu culture, the culture has now been transformed through social media into symbolic consumption and play culture.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.5
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• pp.126-135
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• 1995

An exhaust muffler is one of the simple and effective means to meet the demand for a quiet vehicle, and it deserves a close attention to effectively reduce the engine noise. The transfer function technique is one of the tools that have been used to analyze the noise characteristics of the exhaust muffler. In this paper we obtained a transfer function using the forward-going and backward-going components of sound pressure in the exhaust muffler, which is compatible wiht lattice filter algorithm. This form of transfer function is obtained for the basic elements of a muffler, such as uniform tube, open termin- ation, closed termination, anechoic termination, expansion, contraction, extended-tube resonator, hole, Helmholtz resonator, and concentric hole-cavity resonator. The results are combined to produce the transfer function of various types of mufflers. With this transfer function we calculate the transmission and insertion losses of mufflers, and examined the effects of various design parameters. Comparisons were made between the calculation and experimental results, which showed a good agreement, and we conclude that the transfer function of lattice form can be used to analyze the noise characteristics of the exhaust mufflers.

• Journal of Information Technology Services
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• v.22 no.1
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• pp.29-42
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• 2023

Amid the global movement to harness individual data and boost the data economy, MyData services that utilize personal data are being implemented in earnest in the financial sector in Korea due to the government's active encouragement policy. To this end, MyData service providers must have a service system for business operators that collects and efficiently loads personal information scattered in various financial institutions with individual consent, and comprehensively analyzes and provides it. The system must not only have strict security management capabilities, but also be built in a flexible form that takes into account future data scalability and additional services. In this paper, it has been proposed to be implemented the essential functions that MyData service system must have and the core functions that can manage the entire data life cycle from data collection, distribution to disposal in the form of a platform. In addition, the strengths of the platform structure were reviewed, and the effectiveness of the platform model was examined upon application.

• Corrosion Science and Technology
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• v.22 no.3
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• pp.137-152
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• 2023

Polarization behavior and corrosion inhibition of copper in acidic chloride solutions containing benzotriazole were studied. Pourbaix diagrams constructed for copper in NaCl solutions with different BTAH concentrations were used to understand the polarization behavior. Open circuit potential (OCP) depended not only on chloride concentration, but also on whether a CuBTA layer was formed on the copper surface. Only when the (pH, OCP) was located well in the CuBTA region of the Pourbaix diagram, a stable corrosion inhibiting CuBTA layer was formed, which was confirmed by X-ray Photoelectron Spectroscopy (XPS) and a long-term corrosion test. The OCP for the CuBTA layer decreased logarithmically with increasing [Cl^-] activity in the solution. A minimum BTAH concentration required to form a CuBTA layer for a given NaCl concentration and pH were determined from the Pourbaix diagram. It was found that 320 ppm BTAH solution could be used to form a corrosion-inhibiting CuBTA layer inside the corrosion pit in the sprinkler copper tube, successfully reducing water leakage rate of copper tubes. These experimental results could be used to estimate water chemistry inside a corrosion pit.

• Advances in concrete construction
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• v.15 no.1
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• pp.63-74
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• 2023

All production and consumption activities produce wastes, which often cause damage to our environment and multiple risks to the human health. The valorization of these wastes in concrete technology is a future solution that will allow finding other construction materials sources, optimizing energy consumption and protecting the environment. Among these wastes, there is the marble waste. Every year, huge amount of marble waste is discarded as dust or aggregates form, in open-air storage areas causing serious problems for the environment and public health. In this context, the incorporation of marble waste as a replacement of ordinary aggregates or cement in concrete composition is actively investigated by researchers. This paper presents a comprehensive review of published studies over the last 20 years, dealing the effect of marble waste on fresh and hardened properties of concrete. Most of the studies carried out have used marble waste as dust with substitution rates between 5 and 20%. Besides the economic and ecological benefits, this review showed that marble waste can improve the physical, mechanical and durability properties of concrete. This improvement depends on the form (dust, fine aggregate or coarse aggregate), substitution method (as cement or aggregates replacement) and substitution rate of marble waste. Additionally, the review results showed that the use of 10-15% of marble waste dust as cement substitution can lead to increase the compressive strength.

• Journal of Distribution Research
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• v.12 no.4
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• pp.1-25
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• 2007

The purpose of this study is to provide the strategic implication of the Korean open air market by examining the factors affecting customer loyalty for various market segments as their competitive environment becomes more turbulent. We have undertaken empirical research that uses the methodology of a mixture regression modeling, as a way to ascertain the determinants of customer loyalty toward the Korean open air market, which should form the base of strategy for each segment. We construct a mixture regression model which uses perceived the Korean open air market value dimensions as explanatory variables, an income as a covariate variable, and a customer loyalty as a dependent variable. The analysis of results show that customers are statistically divided into four segments: 'Accessibility'(33.7%), 'Price'(29.7%), 'Shopping environment,'(22.0%), and 'Merchandising,'(14.5%) groups. The findings also showed that parameter estimates are different for each group, which indicates that the sensitivity to changes in the Korean traditional market perceived value and the income variable affecting customer loyalty vary among segments.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.7
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• pp.1397-1404
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• 2015

Recently, high data rate transmission is required in maritime communication. In this paper, we consider multiple input multiple output (MIMO) spatial multiplexing (SM). However, the performance of SM is severly degraded due to spatial channel correlation and line-of-sight (LOS) component. In the maritime communication, the MIMO channel correlation and LOS are critical due to the lack of scatteres around the transmitter and/or the receiver. When the feedback of channel information is available, precoding can enhance the error performance by exploiting the channel information. However, it is difficult to derive closed-form solution considering both the correlation and LOS. In this paper, we present open-loop precoding-based spatial multiplexing transmission method by showing that the effect of performance for the correlation and LOS. It is shown that the open-loop precoding can mitigate the performance degradation due to the LOS as well as the correlation. Consequently, we expect that the proposed open-loop precoding can be adopted to the maritime communication system.

• Journal of Korean Society of Archives and Records Management
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• v.16 no.1
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• pp.121-150
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• 2016

This paper reports the evaluation of six open-source software systems for participatory digital archives. This is an effort to create a digital platform for the social memory of No Gun Ri, which was first recognized in 1999 as a civilian massacre. The process of how it was reported and investigated is critical to understanding this brutal incident. In addition, the course of its cultural recovery has witnessed the reconstruction of the No Gun Ri memory. Thus, it is important to embrace the social memory around the massacre in these archives. In consideration of a virtual space for memory, this study takes the form of participatory archives to provide a mechanism in which anyone can share their memories. As a way to find a digital archives system for No Gun Ri, this study analyzed open-source software based on identified functions and requirements for participatory digital archives. Knowing the details of digital systems, this study discussed how contents for social memory can be stored and used in a digital system.

• Journal of The Korean Association For Science Education
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• v.32 no.10
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• pp.1489-1501
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• 2012

The purpose of this study was to search for effective strategies on teaching open-inquiry by comparing students' and teachers' recognition of its difficulties and helpful strategies. This study focused on the cases of science high school students and their teachers, who carried out open-inquiry to participate in KYPT. This research was conducted through participant observation, questionnaires, and interviews. The research findings were as follows: students stated that planning and doing experiments were the most difficult parts, whereas teachers viewed that their students had difficulties in analyzing data and making a conclusion. With respect to the effective strategy, students stated that they gained many ideas from peer discussions although they have had to carry out their individual tasks. On the contrary, teachers thought that reference materials and the discussions with teachers were most helpful. There were clear differences between students' and their teachers' recognition toward open-inquiry and the gap needs to be closed. Consequently, it would be useful to guide students to form teams and to spend more time in peer discussions especially when doing experiments and to encourage teachers to understand students' actual difficulties and needs.