• Smart Structures and Systems
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• v.3 no.2
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• pp.189-200
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• 2007

As a functional material, shape memory alloy (SMA) has attracted much attention and research effort to explore its unique properties and its applications in the past few decades. Some of its properties, in particular the electrical resistance (ER) based self-sensing property of SMA, have not been fully studied. Electrical resistance of an SMA wire varies during its phase transformation. This variation is an inherent property of the SMA wire, although it is highly nonlinear with hysteresis. The relationship between the displacement and the electrical resistance of an SMA wire is deterministic and repeatable to some degree, therefore enabling the self-sensing ability of the SMA. The potential of this self-sensing ability has not received sufficient exploration so far, and even the previous studies in literature lack generality. This paper concerns the utilization of the self-sensing property of a spring-biased Nickel-Titanium (Nitinol) SMA actuator for two applications: ER feedback position control of an SMA actuator without a position sensor, and estimation of the opening of a SMA actuated valve. The use of the self-sensing property eliminates the need for a position sensor, therefore reducing the cost and size of an SMA actuator assembly. Two experimental apparatuses are fabricated to facilitate the two proposed applications, respectively. Based on open-loop testing results, the curve fitting technique is used to represent the nonlinear relationships between the displacement and the electrical resistance of the two SMA wire actuators. Using the mathematical models of the two SMA actuators, respectively, a proportional plus derivative controller is designed for control of the SMA wire actuator using only electrical resistance feedback. Consequently, the opening of the SMA actuated valve can be estimated without using an extra sensor.

• Journal of the Korean Institute of Educational Facilities
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• v.26 no.1
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• pp.9-16
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• 2019

The recent decline in the school-age population has led to a more conservative and conservative approach to the establishment of schools. In the judgment of school establishment, it is required to make a decision method that can make objective and comprehensive judgment of various situations rather than local analysis of a single school. In this changing situation, EduFine system and placement establishment system were introduced to comprehensively analyze the feasibility of student placement and school establishment. However, the EduFine system of the Ministry of Education has few users because it is difficult to use education and it is difficult for users to use. Based on the GIS, the placement establishment system was able to analyze the number of students and the status of apartment buildings in a comprehensive manner. But placement establishment system has been used mainly in support of investment assessment rather than research. Therefore, there is a need to increase the utilization of users by linking two systems or integrating them into one system. In this study, we want to derive the functions to improve the GIS - based layout establishment system through user analysis such as comparative analysis and survey of existing systems. In particular, the purpose of the study is to improve the function of system, to improve the students' placement ability and the school establishment work ability and to improve the user satisfaction.

• Journal of the Institute of Convergence Signal Processing
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• v.22 no.3
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• pp.110-115
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• 2021

With the era of the 4th Industrial Revolution, education on artificial intelligence is one of the important topics. However, since existing education is aimed at knowledge, it is not suitable for developing the active problem-solving ability and AI utilization ability required by artificial intelligence education. To solve this problem, we proposes PBL-based education method in which learners learn in the process of solving the presented problem. The problem presented to the learner is a completed project. This project consists of three types: a classification model, the training data of the classification model, and the block code to be executed according to the classified result. The project works, but each component is designed to perform a low level of operation. In order to solve this problem, the learners can expect to improve their computational thinking skills by finding problems in the project through testing, finding solutions through discussion, and improving to a higher level of operation.

• Fire Science and Engineering
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• v.27 no.1
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• pp.52-59
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• 2013

In this study, tests were conducted to establish a fire engine of relay waterproof and utilization in order to maintain the pressure in a situation that require high-pressure water-resistant such as a high-rise building fire, etc. As a result of test on the change of a relay waterproof pressure, the measurement result with the hydrant intake of a fire engine opened has reduced approximately 20 % compared to the measurement result with the hydrant intake closed. Similar efficiency showed in the test result that change the pressure of 2 fire engines respectively to use them more efficiently at a fire fighting activity site. A fire engine operation and utilization is proposed based on this study result in order to cope effectively with a fire site requiring high-pressure stream in a high-rise building fire, etc. by using a fire engine held at present because there is no fire pump with high-pressure stream ability arranged at the fire station and there is no regulation on high-pressure fire-fighting pumps in a type approval and verification technology criterion for a fire engine.

• The Korean Journal of Emergency Medical Services
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• v.20 no.1
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• pp.41-55
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• 2016

Emergency statistics for cities and provinces are currently derived using simple results of comparative numerical data, but there is a limit to the ability to analyze and compare deviations relevant to a specific city and province. This study aims to derive various correlations through statistical analysis of emergency and rescue data for Gwangju Metropolitan City and to develop an analytical model that can be applied nationwide. With the new statistical model, further detailed analysis is possible beyond simple evaluation of rescue data, through links to other institutions and analyses using keywords from Internet portal sites and social networks. Second, a system which that can analyze data that are not shared is required. Through this system, a large amount of data can be automatically analysed in real time. Third, the results should flow back for application in various policies. A real-time monitoring and management system should be created for abnormal patterns of disease. In addition, the results should be available to tailor services for individuals, communities, or specific organizations.

• Journal of Microbiology and Biotechnology
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• v.29 no.12
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• pp.1904-1915
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• 2019

Resistant starch (RS) is metabolized by gut microbiota and involved in the production of short-chain fatty acids, which are related to a variety of physiological and health effects. Therefore, the availability of RS as a prebiotic is a topic of interest, and research on gut bacteria that can decompose RS is also important. The objectives in this study were 1) to isolate a human gut bacterium having strong degradation activity on non-gelatinized RS, 2) to characterize its RS-degrading characteristics, and 3) to investigate its probiotic effects, including a growth stimulation effect on other gut bacteria and an immunomodulatory effect. Bifidobacterium adolescentis P2P3 showing very strong RS granule utilization activity was isolated. It can attach to RS granules and form them into clusters. It also utilizes high-amylose corn starch granules up to 63.3%, and efficiently decomposes other various types of commercial RS without gelatinization. In a coculture experiment, Bacteroides thetaiotaomicron ATCC 29148, isolated from human feces, was able to grow using carbon sources generated from RS granules by B. adolescentis P2P3. In addition, B. adolescentis P2P3 demonstrated the ability to stimulate secretion of Th1 type cytokines from mouse macrophages in vitro that was not shown in other B. adolescentis. These results suggested that B. adolescentis P2P3 is a useful probiotic candidate, having immunomodulatory activity as well as the ability to feed other gut bacteria using RS as a prebiotic.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.313-313
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• 2022

The Smilacis chinae Radix refers to the root of Smilax chinae L distributed in mountain and filed of Korea, and it is a vine shrub in the Lilaceae family, called Berchemia berchemiaefolia, and is referred to as Smilacis chinae Radix in it's a natural medicine name. Antibacterial, inflammatory, and antioxidant activity were studied in Smilacis chinae Radix. In this study, biological activities such as antioxidant (DPPH, ABTs, TPC), cytotoxicity, wrinkle improvement, and whitening improvement to increase the utilization value of Smilacis chinae Radix and identify the botanical value. Therefore, we tried to explore the applicability of Smilacis chinae Radix as a functional cosmetic material. Smilacis chinae Radix (SCR) was dried and extracted with ethanol. In order to measure the biological activity of the SCR, antioxidant activity, inhibition activities of collagenase, tyrosinase and cell viability were measured. The DPPH (1,1-diphenyl-2-picryl hydrazyl) radical scavenging activity in the extract with a concentration of 400㎍/mL is 91.22% ± 0.41%%. ABTs (2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity in the extract with a concentration of 400㎍/mL is 99.60% ± 0.03%. Total polyphenol contents (TPC) are 0.203 ± 0.05 mg GAE/mg Ext when SCR was lmg/mL. And the Cell viability for HaCaT derived human keratinocyte and Raw264.7, a mouse-derived macrophage was determined using the MTT assay. When cell was treated with 100㎍/mL of SCR, HaCaT cell showed cell viability of 78.09 ± 0.1% and Raw264.7 cell showed cell viability of 91.88 ± 0.42%. From the above results, we have shown the possibility that the CSR have antioxidant ability, inhibition activity of collagenase and tyrosinase and cell safety ability which can be useful in a functional cosmetic material.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.3807-3818
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• 2015

The objective of this study is to develop an on-line system for improving undergraduate students' competency development. After drawing elements necessary for the competency development such as assessment and planning, competency development, analysis of competency assessment, portfolio, analysis of job ability and community, based on the literature research related to competency and the analysis of the existing system, the direction of the system design was set up. The system was developed by using Microsoft Windows operating system in Windows server, ORACLE ver.10 as its database management system, and JSP and JAVA as its programing language. Reviewing errors and improvements of the system, it was modified and complemented. In order to examine the content functional utilization of the final competency development system, the utilization was verified. The competency development system for undergraduate students can be used as on-line space filled with the internalization of knowledge, self-directed competency development, convenience of record management and interactions between students-professors-alumna, owing to its functions such as boosting competency activities, cultivating career-pioneering ability and introspecting. When it is rare to find researches on the competency development system for undergraduate students, it is expected to be helpful to the development of competency education and the career education for undergraduate students as a new alternative for the competency development.

• Asia-Pacific Journal of Business
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• v.12 no.4
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• pp.271-288
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• 2021

Purpose - The purpose of this study is to identify the critical factors that restaurant management should consider strategically when making a decision after COVID-19 under the digital transformation and non-contact service expansions environment. Design/methodology/approach - The thirty six experts and managers who have 5 years or more experience in restaurant industry in Korea participate this study. The Analytic Hierarchy Process (AHP) and SER-M were used to analyze the experts' opinion Findings - As a result of the analysis, 'management environment' (0.313) showed the highest relative importance priority, followed by 'brand (0.263)', 'management characteristics (0.254)', and 'physical factors (0.17)'. And, as for the sub-factor value, 'lifestyle (0.087)', 'awareness (0.084)', 'consumer desire (0.075)', and 'loyalty (0.068)' were ranked highest among the 19 influencing critical factors. Research implications or Originality - In the case of large restaurant enterprises, it is judged that the subject(CEO, Management) is actively pursuing a strategy to acquire the necessary resources for the given environment of digital transformation and customer demand for non-contact services. On the other hand, in the case of middle and small restaurant enterprises, it seems that they are fully aware of the demand for expansion of non-contact services and the digital transformation required in the post COVID-19 era, but information technology utilization ability, usage experience, technology acceptance ability, and education and training support for this are only available to large enterprises.

• Journal of dental hygiene science
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• v.23 no.4
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• pp.271-281
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• 2023

Background: This study aims to improve dental hygiene education by investigating the relationship between metacognition, learning flow, and problem-solving abilities in dental hygiene majors. Methods: A survey was conducted on 2nd to 4th-year students from dental hygiene programs, with 132 responses analyzed. Data analysis involved t-tests and ANOVA to examine the differences in metacognition, learning flow, and problem-solving abilities based on the general characteristics. Multiple regression analysis was employed to investigate the factors influencing the dependent variable, which is problem-solving abilities. The collected data were analyzed using SPSS. Results: First, when comparing metacognition, learning flow, and problem-solving abilities based on the general characteristics of the study participants, statistically significant differences were observed in common factors such as major satisfaction, subjective academic performance, GPA (grade point average), and reason for major choice (p<0.05). Second, it was found that there is a significant positive correlation between metacognition, learning flow, and problem-solving abilities in dental hygiene students (r≥0.79, p<0.05). In other words, higher levels of metacognition and learning flow were associated with better problem-solving abilities. Third, factors influencing problem-solving abilities were identified, with both metacognition and learning flow having a statistically significant positive impact. It was also noted that metacognition had a greater influence on problem-solving abilities compared to learning flow (adjusted R²=0.815, p<0.05). Conclusion: To enhance the core competency of problem-solving abilities, it is essential to improve metacognition and learning flow. To enhance metacognition and promote learning flow, strategies such as goal setting, utilizing effective learning methods, boosting self-efficacy, managing the learning environment, choosing activities that foster immersion, stress management, self-assessment and feedback integration, improving focus, and utilization a variety of learning experiences will be necessary.