• Journal of Industrial Convergence
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• v.21 no.8
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• pp.35-42
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• 2023

Recently, electronic devices with bendable electronic devices based on flexible substrates are being sold, and therefore, the purpose of this study is to evaluate the possibility of flexible substrates of conductive transparent tapes. As a transparent electrode, carbon nanotube (CNT) was formed by the coating method developed by the research team, and samples coated up to 5 times were fabricated. The surface resistance and transmittance of the substrate were measured, and both resistance and transmittance decreased as the number of CNT coatings increased. After the tape was detached from the glass, the surface resistance slightly increased in all samples, and the transmittance increased by about 10% in all measured wavelength ranges because the glass was removed. Next, the tape coated with CNT twice was used to a bending test 20,000 times under the condition of a radius of curvature of 2 mm. The electrical and optical properties before and after bending did not change, which means that there was no change in CNT properties due to bending.

• Asia Marketing Journal
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• v.12 no.4
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• pp.113-136
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• 2011

Product harm crises can distort long standing favorable equality perceptions, tarnish a company's reputation, cause major revenue and market-share losses, lead to costly product recalls, and devastate a carefully nurtured brand equity. However, in spite of the devastating impact of product-harm crises, little systematic research exists to asses its marketing consequences. So, this study focuses on the negative publicity about companies and their products. Namely, this study presented how inclusion effect supported the relationship between negative publicity and consumers' response, market performance. According to the results, after negativity publicity was happened, it was appeared that the negativity image spread into other product lines(spillover effect; inclusion effect). Also, when they contact with the negative publicity, respondents negatively evaluated both production evaluation and corporate evaluation. And, in that case of the products with negativity publicity, compared with refutation strategy(defense strategy<study 2>), improving strategy(correction notice) had positive influence on recovery of sales, product evaluation, and corporate evaluation. Finally, as the reaction time toward negativity publicity was faster, the market performance got worse. Especially, according to two-way interaction, when the reaction time was fast, the difference between refutation strategy(defense strategy<study 2>) and improving strategy was not existed in product evaluation and corporate evaluation. However, when the reaction time was late(after a month), improving strategy had more positive evaluation than defense strategy in product evaluation, and corporate evaluation.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.3
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• pp.184-191
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• 2023

With increasing corrosion in RC (Reinforced Concrete) structures, cracks occurred due to corrosion products and bearing load resistance decreased. In this study, corrosion was induced through an accelerated corrosion test (ICM: Impressed Current Method) with 140 hours of duration, and changes in USV (Ultra-Sonic Velocity), flexural failure load, and corrosion weight were evaluated before and after corrosion test. Three levels of cover depth (20 mm, 30 mm, and 40 mm) were considered, and the initial cracking period increased and the rust around steel decreased with increasing cover depth. In addition, the USV linearly decreased with decreasing cover depth and increasing amount of corrosion. In the flexural loading test, the bending capacity decreased by more than 10% due to corrosion, but a clear correlation could not be obtained since the corrosion ratio was small, so that the effect of slip was greater than that of reduced cross-sectional area of steel due to corrosion. As cover depth increased, the produced corrosion amount and USV changed with a clear linear relationship, and the cracking period due to corrosion could be estimated by the gradient of the measured corrosion current.

• Journal of Practical Engineering Education
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• v.14 no.3
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• pp.535-541
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• 2022

Zoom has been most popularly used as a non-face-to-face online class tool since COVID19, but due to the recent spread of the metaverse, the use of the metaverse platform is increasing. In particular, since a metaverse platform 'Spatial' provides online classroom creation and various learning functions, and various interactions between instructors and learners or learners and learners are possible, it is highly likely to be used in university classes. Since Zoom and Spatial each have their own strengths and weaknesses for the purpose of class use, it is necessary to find out the strengths and weaknesses of each by comparing and analyzing the learner's experience in class use. In this study, a quantitative analysis of usability, immersion, and satisfaction and a qualitative analysis of individual opinions were performed in order to compare and analyze the learner's experience. SUS (System Usability Scale) was used for usability evaluation, and Magnitude Estimation method was used for immersion and satisfaction evaluation. Thirty-five people who had participated in classes using Zoom and Spatial participated as subjects in this study. Zoom was higher than Spatial at the significance level of 0.05 in usability and satisfaction. On the other hand, the immersion in class was higher in Spatial than in Zoom. Since Spatial provides online classroom creation and various learning functions, and provides various interactions and fun elements between instructors and learners or learners and learners, the immersion in classes was high. If the user interface and interaction of Spatial are improved in the future, it is judged that it can be used as an effective online teaching tool that can replace zoom in university classes.

• Journal of Korea Port Economic Association
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• v.39 no.2
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• pp.111-128
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• 2023

Due to the coronavirus pandemic, interest in outdoor leisure activities is growing. Among outdoor leisure activities, marine sports can be seen as having good conditions to enjoy in Korea. In the case of yachting among marine sports, a number of yacht experience programs have recently been operated centered on Gwanganli and Suyeong Bay in Busan. This yacht experience is an attractive tourism product that can be enjoyed casually, and can bring stress relief to many users. This study tried to verify the effect of the attractiveness of the yacht experience on the stress recovery based on the tourists' experiences using the yacht experience tour. In addition, we tried to verify the intention of revisiting the yacht experience or sharing it with others through SNS through this stress recovery. In addition, as a moderator variable, the difference between the MZ generation and other generations, which use SNS more actively than other generations, was presented and its significance was verified. The survey of this study was conducted online for tourists who experienced yacht experience in Busan. As a result of the analysis, among the attractive factors of the yacht experience, the program, landscape, facilities and service was found to have a significant influence on the users' stress recovery, and satisfaction through stress recovery had a significant effect on the intention to revisit and to share the SNS. In the verification of the moderating effect according to age, a generational difference in revisit intention between the MZ generation and other generations was confirmed. Through this study, it was suggested that various programs of yacht experience should be developed to induce users to revisit, and various marketing using SNS should be carried out.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.7
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• pp.950-957
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• 2023

For safe mooring and towing between the ship and port, the equipment must be designed in accordance with the relevant international regulations. However, some small shipyards and engineering companies often do not fully comprehend the core contents. Therefore, the international regulations regarding towing and mooring equipment are reviewed and the bollard and chock are newly developed based on the Mooring Equipment Guideline 4 (MEG4) standards. A bollard is a mooring equipment used to fix a mooring rope to the hull. It has two columns and is mostly used in a figure eight pattern knots under the mooring condition. The chock, which is used to change the mooring rope direction coming into the ship from outside, is manufactured using a casting with curvature. The two mooring equipment are widely used in the stern, bow, and mid-side. Owing to the increase in the size of container vessels and LNG ships, the mooring rope load has increased and the safe working load of the mooring equipment must be revised. This study summarizes and examines the results of the allowable stress method obtained using finite element analysis modelling. To consider the mesh size effect, a reasonable criteria was suggested by referring the existing class guidance. Additionally, the safe working load was verified through nonlinear collapse analysis, and the elastic region against load increments was confirmed. Furthermore, the proposed evaluation method can be used to develop similar equipment in the near future.

• Journal of Korean Society of Disaster and Security
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• v.16 no.2
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• pp.57-63
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• 2023

Recently, Heavy rains and super typhoons occurred by climate change cause a lot of damage in Korea. In order to reduce such damage, various types of river maintenance projects are being promoted, but it is difficult to maintain the balance of rivers in Korea with distinct flood and dry seasons. In particular, river structures installed as a river maintenance project cause various problems such as scouring of structures and their foundations during floods and river bed changes. In order to reduce such bed scour, various vanes are installed in the bend of the river, and various bed scour reduction effects appear depending on the size, arrangement, and shape of the vanes. The vane regenerates the secondary flow in the opposite direction to the secondary flow generated by the centrifugal force, thereby reducing scour around the outer bed and promoting deposition. The theory of this study uses the governing equation applying the continuity equation that satisfies the law of conservation of mass and the momentum equation that satisfies the conservation of momentum, and measures the overall average flow velocity change rate according to design factors to investigate the effect of vanes under various conditions. Both the average and cross-sectional flow velocities decreased in both the trapezoidal vane and the square vane. In addition, vanes installed perpendicularly or inclined to the direction of river flow generate a secondary flow in the opposite direction to the secondary flow generated by centrifugal force, thereby canceling the secondary flow of centrifugal force, so the effect of the vane appears.

• Journal of the Korean Society of Radiology
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• v.17 no.6
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• pp.977-983
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• 2023

Due to the development of the domestic economy and science, the people's standard of living has increased. Accordingly, we want to improve the quality of life. In other words, we guarantee human rights and pursue dignity and value as human beings. Therefore, the medical field extends human life and helps maintain a healthy life. The social medicine that protects human rights is forensic medicine. Forensic medicine identifies deaths and analyzes the cause using forensic radiology images. Forensic radiology is the acquisition and provision of medical images by the radiographer. Therefore, the radiographer must have expertise by completing forensic science-related courses. Recently, medical and nursing schools have opened and operated various subjects such as forensic medicine and forensic nursing. However, the Department of Radiology science is the only school that offers courses related to forensic science. For the future development and exploration of the radiographer and department of radiology science, forensic education should be considered. For this purpose, we investigated the necessity and demand for forensic education in the department of radiology science undergraduate and graduate schools. The department of radiology science students' awareness of forensic science was found to be 2.977 points, but the need for forensic science education for the radiographer was high at 3.759 points. In addition, current students' demand for forensic science courses was high at 84.1%, with the majority responding that it was necessary to open and operate the course. This study was able to determine the demand for forensic science-related subjects among the department of radiology science undergraduate and graduate students, and there is a need to explore diversity and expertise in education. We hope that it will be used as basic data for the development of forensic medicine and radiology science.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.6
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• pp.86-93
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• 2023

As the hysteretic behavior of reinforced concrete members under cyclic loading progresses, the energy dissipation ability decreases due to a decrease in stiffness and strength and pinching effects. However, the guideline "Nonlinear Analysis Model for Performance-Based Seismic Design of Reinforced Concrete Building Structures, 2021" requires calculating a single energy dissipation factor for each member and all histeric step, so the decrease in energy dissipation capacity according to histeric step cannot be considered. It is judged that Therefore, in this study, the energy dissipation factor according to the histeric step was examined by comparing the existing experimental results and the nonlinear time history analysis results for a general beam under cyclic loading. The energy dissipation factor was calculated as the ratio of the energy dissipation amount of the actual specimen to the energy dissipation amount of the idealized elastoplastic behavior obtained as a result of nonlinear time history analysis. In the existing experiment results, the energy dissipation factor was derived by calculating one cycle for each histeric step, and the energy dissipation factor was derived based on the nonlinear modeling process in the guidelines. In the existing experimental study, the energy dissipation factor was calculated by setting each histeric step (Y-L-R), and the energy dissipation factor was found to be 0.36 in the Y-L step and 0.28 in the L-R step, and the energy dissipation factor in the guideline was found to be 0.31. This shows that the energy dissipation factor calculation formula in the guidelines does not indicate a decrease in the energy dissipation capacity of reinforced concrete members.

• Korean Chemical Engineering Research
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• v.61 no.4
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• pp.542-549
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• 2023

Since the growing interest in surrogate modeling, there has been continuous research aimed at simulating nonlinear chemical processes using data-driven machine learning. However, the opaque nature of machine learning models, which limits their interpretability, poses a challenge for their practical application in industry. Therefore, this study aims to analyze chemical processes using Explainable Artificial Intelligence (XAI), a concept that improves interpretability while ensuring model accuracy. While conventional sensitivity analysis of chemical processes has been limited to calculating and ranking the sensitivity indices of variables, we propose a methodology that utilizes XAI to not only perform global and local sensitivity analysis, but also examine the interactions among variables to gain physical insights from the data. For the ammonia synthesis process, which is the target process of the case study, we set the temperature of the preheater leading to the first reactor and the split ratio of the cold shot to the three reactors as process variables. By integrating Matlab and Aspen Plus, we obtained data on ammonia production and the maximum temperatures of the three reactors while systematically varying the process variables. We then trained tree-based models and performed sensitivity analysis using the SHAP technique, one of the XAI methods, on the most accurate model. The global sensitivity analysis showed that the preheater temperature had the greatest effect, and the local sensitivity analysis provided insights for defining the ranges of process variables to improve productivity and prevent overheating. By constructing alternative models for chemical processes and using XAI for sensitivity analysis, this work contributes to providing both quantitative and qualitative feedback for process optimization.