• Special Issue of the Society of Naval Architects of Korea
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• 2015.09a
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• pp.50-55
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• 2015

Application of newly conceptualized Anti-Splash Devices designed for COT vent pipes were studied on a P/V valve located on the upper deck of an oil carrier vessel. Anti-Splash devices are used in the shipbuilding industry in order to avoid oil overflow and spray accidents caused by excess pressure and vacuum condition in the cargo oil tanks. These conditions are caused by the transverse and longitudinal sloshing forces that arise from ship motion during sea voyages. The main issue with existing Anti-Splash device model is flux at the outlet of the Anti-Splash Device, and so, new conceptual models for the Anti-Splash device were developed and compared to existing Anti-Splash device model using CFD analysis. Transient analysis was used to capture the flow and velocity of each model and a comparative analysis was performed between old and new-concept models. This data was used to determine the optimal design parameters in order to develop an optimized Anti-Splash Device. A Factory acceptance test was performed on the new-concept models in order to verify the performance and efficiency against their design requirements and other criterion. The final step performed was to apply the optimized Anti-Splash Device models for COT vent pipes to an actual vessel and verify performance through a seawater cargo operation during a sea voyage as per the ship owner's request. The patent for the aforementioned device was obtained by the Korean Intellectual property Office dated Dec. 18th,2014.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.8
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• pp.630-640
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• 2003

As tunnel ventilation has recently been playing a major role in the tunnel construction and maintenance, longitudinal ventilation systems with jet fans have been utilized a great deal because they are economical and effective. However, due to the length of tunnels and heavy traffic, it is hard to take the field measurements. In this study, therefore, the computer simulation and the model experiment of producing a wind tunnel were carried out simultaneously and the results were compared. The ultimate objective of this research was to interpret the air flow pattern inside the tunnel with a jet-fan was set up, and to offer the useful data for jet-fan installation and operation. The experiment was carried out with varying the jet-fan diameters, location of installation, the discharge velocity. Result showed that as the initial static pressure came up with the negative pressure, the tunnel air flowed into the inside of tunnel from outside due to the entrainment-effect and the backflow-phenomenon by separation-effect was observed in the lower half part of the tunnel. As the jet-fan was getting closer to the tunnel wall, the entrainment-effect caused by the interaction with the wall was increased; however, the mixing distance and irregular flow section became longer, and also the air pressure loss generated by wall friction was large.

• Journal of the Korea Society of Computer and Information
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• v.13 no.5
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• pp.279-289
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• 2008

This study has the primary purpose to understanding the present situation through research on the actual condition about human resource outsourcing in the stocks and KOSDAQ enterprises, and would give the basic and useful data to develop human resource outsourcing. Data were collected from 1,500 charge of human resource management in the stocks and KOSDAQ enterprises which introduced or will be introduced human resource outsourcing. Frequencies, cross-tabs and independent-samples t-test were used to understanding the actual condition. Research findings are summarized as follows. First, as the introduction area of human resource outsourcing following training and development on the list were personnel information system, recruitment and selection. Second, tasks that transfer outsourcing supply firms owing to human resource outsourcing were common and typical operation function than complex and specific planning function.

• The Journal of Korean Society for School & Community Health Education
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• v.19 no.2
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• pp.53-63
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• 2018

Objectives: This study was intended to provide resources for the development and operation of the elderly's oral health education programs by comparing the difference of oral health behavior, oral health care self-efficacy and oral health levels according to their oral health education experiences and by researching the correlation of oral Health Behavior, self-efficacy, subjective oral health level and oral health education experience. Methods: An interview survey using structured questionaries was done on 180 senior citizens older than 65 years old residing in some areas of Gyeonggi-do from April 19 to May 25, 2018. The data was analyzed with Chi-square, t-test, spearman correlation coefficient with the use of SPSS 20.0. Results: 1. Those who are older than 75 years old and have higher levels of education and finance have more experiences of oral health education. 2. Those who have experiences of oral health education brush their teeth more than three times a day, use more oral health care items and get more regular preventive treatments such as oral examination and scaling. 3. As they has experiences of oral health education, their oral health behaviors, oral health care self-efficacy(tooth care, dietary control, regular checkup) and subjective oral health levels are high. Conclusion: It is necessary to try to improve the elderly's oral health levels by motivating the importance of oral health care and changing their oral health behaviors positively with the implement of oral health education on the elderly. Especially, oral health education programs that are operated on the elderly should be planned with practical programs that can cause the change of their oral health behaviors and should be processed to reinforce oral health care self-efficacy. Furthermore, preventive treatments for the elderly such as oral health education, oral examination and scaling should be implemented systematically and continuously by policy.

• Journal of the Korean Society of Safety
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• v.34 no.5
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• pp.15-21
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• 2019

A rack-type warehouse has the advantage of storing a large amount in a small area by loading goods vertically. But in terms of fire risk, the fire load is very high, which can cause massive damage in the event of a fire. In the United States, research has been actively conducted to minimize the spread of vertical fires, and relevant standards have been established and operated. In Korea, research and related standards are insufficient to prevent the vertical spread of rack-type warehouse fires. In this study, an experimental study was conducted to prevent the vertical spread of a rack-type warehouse fire using a horizontal barrier and in-rack sprinklers. As a result of the test, the horizontal barrier considering the continuous flame prevented the vertical spread of the flame for a certain time. However, the horizontal barrier with continuous flame did not show the effect of preventing continuous flame. The combination of the horizontal barrier and the in-rack sprinkler prevented the vertical spread of fire effectively. In addition, the heat collecting effect through the horizontal barrier was shown and helped the early operation of the in-rack sprinklers.

• Fashion & Textile Research Journal
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• v.23 no.4
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• pp.469-479
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• 2021

This case study investigates fashion brands that have entered the pet fashion market. A total of 25 cases were identified and analyzed from three perspectives: 1) product types, size systems, prices, 2) design aspects, fabrics, patterns, styles, and 3) marketing strategies. The study results are as follows. First, the product types of pet fashion are not diverse, and only the sizes of small dogs can be found. However, there is a significant price difference between brands. Second, knitted fabrics with good elasticity are mainly used for pet fashion products, and patterns incorporating their brands are extremely common. The style is casual and sporty. Third, marketing strategies should include a new line within a brand or launch a single specialized brand as a one-shot test for consumer reaction. Additionally, it has been expanded and presented as a family look to meet the needs of the petfam. Further, existing fashion brands and retail-based brands select diverse small-scale dog fashion product brands and expand their operation as a dog lifestyle total selectional shop. Therefore, brands entering the future should consider strategies such as size segmentation, product diversification, and premium price of high-quality materials that help market products such as the expansion or promotion of existing brands.

• Journal of the Korea Convergence Society
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• v.12 no.10
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• pp.45-53
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• 2021

In our technology-driven world, various methods for teaching in an educational venue or in a simulated environment have been suggested especially for computer and coding education. In particular, IoT related education has been made possible owing to the industrial developments that have occurred in various fields since the Fourth Industrial Revolution. The proposed model allows various IoT systems to be indirectly built; it provides an inexpensive learning method by applying a simulation system in a 3D environment. The model is implemented on Virtual Remote IO based on the Arduino platform, thereby reducing the cost of building an education system. In addition various education-related content can be provided to learners through such an indirectly developed system. Test code was written to check the consistency of an operation between the real system and the virtual system.

• Journal of IKEEE
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• v.25 no.3
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• pp.571-577
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• 2021

This paper describes ISO/TR 4804, an international standard to describe how to design and verify autonomous cars to ensure safety and cybersecurity. Goals of ISO/TR 4804 are (1) positive risk balance and (2) avoidance of unreasonable risk. It also 12 principles of safety and cybersecurity to achieve these goals. In the design procedures, it describes (1) 13 capabilities to achieve these safety and cybersecurity principles, (2) hardware and software elements to achieve these capabilities, and (3) a generic logical architecture to combine these elements. In the verification procedures, it describes (1) 5 challenges to ensure safety and cybersecurity, (2) test goals, platforms, and solutions to achieve these challenges, (3) simulation and field operation methods, and (4) verification methods for hardware and software elements. Especially, it regards deep neural network as a software component and it describe design and verification methods of autonomous cars.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.9
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• pp.1166-1175
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• 2021

We investigate the current situation and development trend of domestic smart city and emergency vehicle priority signal control system analyzing the existing effectiveness of 1) emergency vehicle priority signal control system and 2) control emergency vehicle priority signal, based on domestic and foreign prior research for signal control system security. The effectiveness of time reduction was analyzed through actual application and test operation to emergency vehicles after establishing the system. In addition, for security management and stable service of real-time signal system control we propose improvement for the technical control items of the ISMS-P certification system to secure golden time to protect citizens' precious lives and property in case of emergency by classifying and mapping the existing ISMS-P certification system and the Korea Internet & Security Agency's cyber security guide according to the items of security threats.

• KEPCO Journal on Electric Power and Energy
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• v.6 no.4
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• pp.455-460
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• 2020

In order to identify the characteristics of fine particle emissions from thermal power plants, this study conducted measurement of the primary emission concentration of TPM, PM₁₀ and PM_2.5 according to Korea standard test method (ES 01301.1) and ISO 23210 method (KS I ISO 23210). Particulate matters were sampled in total 74 units of power plants such as 59 units of coal-fired power plants, 7 units of heavy oil power plants, 2 units of biomass power plant, and 6 units of liquid natural gas power plants. The average concentration of TPM, PM₁₀, PM_2.5 by fuel are 3.33 mg/m³, 3.01 mg/m³, 2.70 mg/m³ in coal-fired plant, 3.02 mg/m³, 2.99 mg/m³, 2.93 mg/m³ in heavy oil plant, 0.114 mg/m³, 0.046 mg/m³, 0.036 mg/m³ in LNG plant, respectively. These results of TPM, PM₁₀ and PM_2.5 were satisfied with the standards of fine dust emission allowance in all units of power plants, respectively. Also, this study evaluated the characteristics of fine particle emissions by conditions of power plants including generation sources, boiler types and operation years and calculated emission factors and then evaluated fine particle emissions by sources of electricity generation.