• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.9
• /
• pp.5795-5801
• /
• 2015

The low temperature distribution of the refrigerated and frozen food has been increased gradually. Refrigeration industry is using R134a refrigerant, which GWP is 1300. R1234yf is an alternative refrigerant of R134a because GWP of R1234yf refrigerant is just 4. Evaporator used in refrigeration truck refrigeration system is operated on low temperature condition. Accordingly, evaporator is formed frost and the formation of frost is rapidly decreased performance of evaporator. In this study, the performance of evaporator using R134a and R1234yf refrigerant was analyzed with operating conditions under frost condition. As a result, the performance of R134a evaporator according to air inlet temperature, relative humidity and evaporating temperature was more sensitive than R1234yf evaporator. Besides, the frost growth of R134a evaporator is steeper than that of R1234yf one.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.36 no.3
• /
• pp.202-210
• /
• 2016

A thermal barrier coating (TBC) has been widely applied to machine components working under high temperature as a thermal insulator owing to its critical financial and safety benefits to the industry. However, the nondestructive evaluation of TBC damage is not easy since sensing of the microscopic change that occurs on the TBC is required during an evaluation. We designed an eddy current probe for evaluating damage on a TBC based on the finite element method (FEM) and validated its performance through an experiment. An FEM analysis predicted the sensitivity of the probe, showing that impedance change increases as the TBC thermally degrades. In addition, the effect of the magnetic shield concentrating magnetic flux density was also observed. Finally, experimental validation showed good agreement with the simulation result.

• Journal of the Korea Society of Computer and Information
• /
• v.26 no.12
• /
• pp.195-200
• /
• 2021

Seafarers play an important role in shipping and logistics. However, seafarers are relatively vulnerable to mental illness because they have to board ships for a considerable period of time and work in isolation. In particular, in the pandemic situation caused by COVID-19, the crew change is delayed due to the closure of many ports around the world, increasing the mental burden on seafarers. The mental health management of the crew is important because these mental problems can lead to major accidents of lives and ships. This paper identified the necessity of mental health management of seafarers through a survey and identified problems with the currently operated mental health management program and curriculum. Especially, this study proposed VR-based programs to help crews receive mentally counseling treatment in a timely manner and to reduce the mental burden on them by preventing sensitive personal information exposure. Through this, it is expected to contribute to the stable development of the logistics industry by establishing a safe seafarers working environment.

• Journal of the Korean Institute of Gas
• /
• v.22 no.6
• /
• pp.104-108
• /
• 2018

Experimental studies have been done to examine the aging characteristics by regulator diaphragms of gas pressure, governor room of city gas. Various testing samples with different service periods were manufactured. The results of SEM observation indicated that the surface and thickness of the samples tested were slightly sensitive to the service periods. It was found that as the service periods increased, the tensile strength of diaphragm samples decreased. For samples over 25 years of service, the strength decreased to approximately 60 % of that of new diaphragms. It was also found that as the service periods increased, the elongation increased.

• Journal of Broadcast Engineering
• /
• v.23 no.6
• /
• pp.800-812
• /
• 2018

In this study, we reviewed recent trends for enhancing human cognitive accessibility to social VR platform. We also proposed a practical method to predict VR sickness and improve the cognitive accessibility. In doing so, we investigated subtle changes in human body sway unconsciously made before, during, and after being exposed to extreme VR experience. The scientific assumption that VR sickness would be correlated with the subtle changes in body sway was validated. We found that participants who showed sensitive changes in the body sway before VR experience, felt more severe VR sickness than others. The findings can be practically applied in predicting susceptibility to VR sickness prior to VR experiences.

• Journal of Convergence for Information Technology
• /
• v.9 no.8
• /
• pp.9-19
• /
• 2019

The effects of artificial intelligence technology is social science research as research on the impact on industry and changes in daily life, etc. This means that developing 'emotion AI' will prepare 'next-generation 3D-vector-sensitive AI'. This suggests the main keywords of the tertiary AI decision-making power. Particularly important results will be achieved because of the importance of current unethical learning and the implementation of decision-making systems that reflect ethical value judgments. This is a data based simulation, and required (1)Available data, (2)the technology for the goal of simulation. This takes into account the general content of the intended simulation based research. Currently, existing researches focus on meaningful research motivation, but this study presents the direction of technology. So, empirical analysis is consistent with the decision-making power of each country vs. new technology firms for AI on ehtic responsibility. As a result, there is a need for a concrete contribution and interpretation that can be achieved for the ethic Responsibility, on the technical side of AI / ML. In AI decision making, analytic power of human empathy should be included tech own trust.

• Journal of the Korean Society of Safety
• /
• v.34 no.1
• /
• pp.40-44
• /
• 2019

Experimental studies have been carried out to investigate characteristics of gas explosion using a multi layered water gel barrier in a vented explosion chamber. The chamber is consisted of 1600 mm in length, with a square cross-section of $100{\times}100mm^2$. The gel concentration of inner layer of MLWGB ranged from 10% to 90% with intervals of 10% by weight of gel. Displacement of the MLWGB was photographed with a measured using a high-speed video camera, and pressure development was measured using a data acquisition system. It was found that MLWGBs with 10 ~ 20% inner layer concentrations were ruptured during the explosions. As the concentrations of inner layer increased from 30% to 90%, the barriers were not ruptured. As the gel concentrations of the inner layer increased, the displacement increased toward the chamber exit and the pressure decreased for the ruptured barriers. It was found that the pressure attenuation obtained from the MLWGB was higher than that of the single water gel barrier. For the cases of non-ruptured barriers, the pressure inside the chamber less increased with increasing gel concentrations of the inner layer. It was also found that the displacement moved back into the chamber for non-ruptured MLWGBs, and it was sensitive to the gel concentrations.

• Journal of Korean Society for Quality Management
• /
• v.46 no.4
• /
• pp.877-898
• /
• 2018

Purpose: This study empirically examines the effect of Communication Privacy Management(CPM) factors and Privacy Calculus factors to the intention to disclose Personal Health Information(PHI) in the context of healthcare ecosystem. Also, it investigates the moderating effects of CPM factors in the relationship between privacy calculus variables and the intention to disclose PHI. Methods: We conducted scenario-based repeated-measures quasiexperiment and used total 364 samples for analysis. Confirmatory factor analysis and repeated-measure ANOVA were employed using SPSS 24.0. Results: All CPM factors, such as type of information, requesting purpose, and requesting stakeholder, directly influence to the intention to disclose PHI, whereas only the medium trust out of the Privacy Calculus factors has direct influence on the intention to disclose PHI. With regard to the moderating effects, the requesting stakeholder is the most influential and the information type is the least influential construct. Conclusion: The findings suggest that healthcare system should be designed to provide more definite and personalized benefits to customers to enhance social and individual benefits by getting more participation from customers. Also, it is desirable that the requesting stakeholder of PHI would be non-profit organizations such as hospital, government or public agencies to secure more willingness of PHI from people. Furthermore, it is implied that extensive information gathering and utilization, instead of excluding sensitive information or critical patients' records, is recommended which is substantial to invigorate the healthcare industry.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.20 no.4
• /
• pp.39-48
• /
• 2021

In this paper, an in-plane deformation measuring system using a dual-beam shear interferometer was constructed to measure the in-plane deformation of the measuring object. The in-plane deformation of the object was quantitatively measured according to the load and surface treatment conditions of the object. We also verified the reliability of the proposed technique by simultaneously performing the technique with an electronic speckle pattern interferometry system (ESPI), which is another laser application measurement technology. Digital shearography directly measures the deformation gradient or strain components and has the advantages of being full-field, noncontact, highly sensitive, and robust. It offers a much higher measurement sensitivity compared with noncoherent measurement methods and is more robust and applicable to in-field tests.

• Journal of the Architectural Institute of Korea Structure & Construction
• /
• v.34 no.1
• /
• pp.53-60
• /
• 2018

For test on flooring board laminated with PVC decoration materials in order to replace the current surface materials such as HPL in decoration wood-based flooring board. the Results of comparison and analysis are as follows: For thermal conductivity, flooring board decorated with PVC did not show huge differences when temperature was rising and lowering compared to the flooring materials laminated with the existing HPL surface materials. It seems the most meaningful results for using it as indoor flooring materials. That is, in Korea where there is the culture focusing on ondol heating, use amount of heat energy and efficiency of flooring materials are very important and sensitive issues, involving immediately with household economy of final consumers, and it might be a criteria to judge basic performances required as flooring materials. As a result of the analysis on mandatory durability test items such as abrasion resistance, absorption width expansion rate, impact resistance, surface hardness, and impact absorption for flooring materials, compared to flooring board laminated with general HPL surface decoration materials, decoration wood-based flooring board laminated with PVC surface decoration materials which is higher abrasion resistance with smaller transformation and has better durability and impact absorption of the surface, is available for actual application as indoor flooring board, and for replacing surface decoration materials impregnated with heat-hardened resion such as HPL.