• Journal of the Korean Society of Propulsion Engineers
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• v.25 no.3
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• pp.62-80
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• 2021

The requirements for the next-generation propulsion system and for a good propellant have been summarized. The characteristics and effectiveness of kerosene, hydrogen, and methane, which are the fuels that are mainly attracting attention in Korea and abroad, were compared with each other. As a result of the comparison, methane was evaluated to be more advantageous than other fuels in reliability, cost, reusability, maintenance, eco-friendliness, safety, lifespan, technical difficulties, engine cycle selection, application of common bulkhead, and non-disassembly/reassembly delivery. And in terms of performance, the specific impulse of methane is higher than that of kerosene, so the efficiency of the launch vehicle can be increased. Methane's properties incluidng eco-friendliness, low-temperature combustion, long life, and maintenability make it beneficial for reuse and for the development of multi-purpose engines.

• Journal of Korean Academy of Nursing
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• v.52 no.5
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• pp.535-549
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• 2022

Purpose: The study aimed to design and develop an automated personalized self-care (APSC) program for patients with type 2 diabetes mellitus. The secondary aim was to present a clinical protocol as a mixed-method research to test the program effects. Methods: The APSC program was developed in the order of analysis, design, implementation, and evaluation according to the software development life cycle, and was guided by the self-regulatory theory. The content validity, heuristics, and usability of the program were verified by experts and patients with type 2 diabetes mellitus. Results: The APSC program was developed based on goal setting, education, monitoring, and feedback components corresponding to the phases of forethought, performance/volitional control, and self-reflection of self-regulatory theory. Using the mobile application, the participants are able to learn from educational materials, monitor their health behaviors, receive weekly-automated personalized goals and feedback messages, and use an automated conversation system to solve the problems related to self-care. The ongoing two-year study utilizes a mixed method design, with 180 patients having type 2 diabetes mellitus randomized to receive either the intervention or usual care. The participants will be reviewed for self-care self-efficacy, health behaviors, and health outcomes at 6, 12, 18, and 24 months. Participants in the intervention group will be interviewed about their experiences. Conclusion: The APSC program can serve as an effective tool for facilitating diabetes health behaviors by improving patients' self-care self-efficacy and self-regulation for self-care. However, the clinical effectiveness of this program requires further investigation.

• The Journal of the Korea Contents Association
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• v.22 no.9
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• pp.614-627
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• 2022

The purpose of this study was to explore the various data and methods employed by HR analytics studies. The researchers selected 78 KCI-indexed empirical articles on HR analytics and categorized them using the Employee Life Cycle framework. This yielded several important findings. First, employee retention has been the most common subject of extant studies, followed by performance management. Second, HR analytics studies have used a variety of data (structured and unstructured) according to their research questions, and the data sources have ranged from organizations' internal systems to national databases. Third, most domestic HR analytics studies have been descriptive and diagnostic, whereas predictive and prescriptive studies have been rare. These results have important theoretical and practical implications for future HR analytics research.

• Education of Primary School Mathematics
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• v.25 no.1
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• pp.19-41
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• 2022

Online classes have become one of the general teaching and learning method in elementary education, and elementary school teachers are essentially required to design and implement online math classes that reflect the characteristics of online environment and the specificity of the subject. The qualitative improvement of online mathematics lessons can start with examining what difficulties teachers actually have in enacting the online lessons, and this study focused on their educational needs by examining the degree to which elementary school teachers perceive and implement in terms of designing online interactions. The result showed that teacher education on Learner-Content Interaction (LC) and Learner-Learner Interaction (LL) was necessary for elementary school teachers designing online mathematics lessons, and the educational needs of detailed items of interactions were confirmed. Furthermore, it was found that there was a difference in educational needs for the types of online interactions according to the career life cycle of elementary school teachers. The instructional design strategies for online interactions in online mathematics lessons and implications for teacher education necessary for elementary school teachers were derived from the result.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.6D
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• pp.727-736
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• 2009

Many of the researchers have tried to enhance the satisfaction of both users and owners of social infrastructures by applying the asset management methodology. This study is to develop more efficient asset management framework for bridge management. Based on various literature review, an asset management procedure for bridge management was suggested, and appropriate practices at each step were given. The suggested procedures include the determination of operation and maintenance strategy, level of service, performance measure, valuation of assets, and decision-makings. In addition, this study suggests an applicable decision-making process for the resource distribution based on the management strategy.

• Fashion & Textile Research Journal
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• v.25 no.3
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• pp.398-408
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• 2023

Smart clothing products can experience a decrease in performance and reliability due to various mechanical, biological, and chemical stress factors that occur throughout their life cycle. These issues can hinder consumer acceptance of the products. This study aims to enhance the reliability of smart clothing and facilitate quality control by analyzing and identifying the current status of international standardization for smart clothing and electronic textiles (e-textiles). The focus of this analysis was on the durability test methods in the use environment. Furthermore, similar standards published by different standardization organizations for durability tests were compared in depth. The study showed that a total of 27 international standards have been developed or are currently under development. The current standardization efforts mainly aim to develop functionality and durability test methods for smart clothing and e-textile products. A detailed comparison was made between two international standards (IEC 63023-204-1:2023 and AATCC TM210:2019) specifically in relation to the washing durability test method and the electrical resistance measurement standards (BS EN 16812:2016 vs AATCC EP13-2021), before and after the environmental exposure tests. Based on this comparison, several suggestions have been made and discussed for the future revision of these international standards.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.172-172
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• 2022

The heading response of 40 genotypes, originated from South Korea, North Korea, and northern China, was tested under the temperature and day-length conditions of thirteen major rice production area in North Korea, with aims to select adaptable varieties to the given environment and crop period for each region. To simulate regional environment, seven-day mean temperature with 10℃ daily temperature range and day-length for each region were imposed at a weekly interval in the walk-in phytotrons. Olbyeo1, Olbyeo2 and Sonbong9 originated from North Korea, Kenjiandao3 and Nongdae3 from northern China, and Joun from South Korea demonstrated the earliest heading stage depending on the regional environment. Thirty-four varieties reached heading stage within the regional safe marginal heading date (SMHD) under Haeju and Sariwon conditions while 16-17 varieties reached the stage under Wonsan, Changjon, Supung, and Yongyon environment. Some of the middle and mid-late maturing varieties originated from South Korea could reach heading stage within SMHD under the temperature and day-length conditions of Kaesong, Haeju, Sariwon, Nampo, and Pyongyang located in west-southern plain. Majority of early maturing varieties, but not middle or mid-late ones, showed heading stage within SMHD under the conditions of Singye, Anju, Kusong and Sinuiju. Only some early maturing varieties demonstrated heading stage within SMHD under Yongyon, Changjon and Wonsan environment. These results provide basic information on the varieties able to complete their normal life cycle under the regional environment in North Korea. It it further suggested that yield performance of the selected varieties for each region in this study be tested to select high yielding rice varieties adaptable to North Korean environment.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.4
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• pp.39-52
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• 2023

In this study, project information of government-funded research institute in the food field was collected and analyzed to systematically identify the factors affecting the process of transferring technological achievements of public research institute to the private sector. This study hypothesized that human resources, financial resources, and technological characteristics as input factors of R&D projects affect output factors, such as research papers or patents produced by R&D projects. Moreover, these outputs would serve as drivers of the technology transfer as one of the R&D outcomes. Linear Regression Analysis and Poisson Regression Analysis were conducted to empirically and sequentially investigate the relationship between input factors and output and outcome of R&D projects and the results are as follows: First, the principle investigator's career and participating researcher's size as human resource factors have an influence on both the number of SCI (science citation index) papers and patent registration. Second, the research duration and research expenses for the current year have an influence on the number of SCI papers and patent registrations, which are the main outputs of R&D projects. Third, the technology life cycle affects the number of SCI papers and patent registrations. Lastly, the higher the number of SCI papers and patent registrations, the more it affected the number of technology transfers and the amount of technology transfer contract.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.5
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• pp.885-894
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• 2023

Setting RAM target value for a defense system plays a crucial role in the development and design phases and the production phase as well. It is apparent that the achieved RAM target value can help maximizing the combat capability of a defense system and improving its performance throughout the system's life cycle from acquisition phase to disposal. Usually a defense system operates according to its OMS/MP (Operational Mode Summary / Mission Profile) and it consists of several subsystems which are supposed to be operated at each utilization rate under its operating conditions and the mission profiles assigned. In this study, a method of setting RAM target value is proposed for a defense system that are composed of several independent subsystems considering their utilization rates and the mission profiles assigned. And the case study of applying the proposed method of setting RAM target value to system A is dealt with.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.6_2
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• pp.1055-1062
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• 2023

Globally, the need for remanufacturing or reusing ships and various mechanical parts continues to increase due to environmental problems including global warming. Research on remanufacturing is being carried out in many areas. However, research on inspection and classification to identify the performance or degree of wear of mechanical parts is insufficient. In particular, studies on the inspection-ability and classification-ability of mechanical parts equipped with various materials and complex forms are highly required. Remanufacturing must be considered from the stage of design to extend the life cycle of mechanical parts. Particularly, it is very important to perform research for evaluating the degree of ease to inspect and classify various sorts of wear or deterioration of parts caused by long-term use easily. In this study, the degree of ease in inspecting or classifying mechanical parts for remanufacturing is defined as inspection-ability and classification-ability. In fact, to remanufacture old parts, inspection-ability and classification-ability should be reflected from the stage of design. The purpose of this study is to evaluate the inspection-ability and classification-ability of ships and various mechanical parts. This researcher has presented the quantitative evaluation procedure of inspection-ability and classification-ability, derived the factors and ranges that influence each of the details of easiness, assigned scores according to the ranges of the factors, and calculated weights. Lastly, this study presents the procedure of scoring to evaluate the overall weights of inspection-ability and classification-ability and also inspection-ability and classification-ability quantitatively.