• Korean Journal of Optics and Photonics
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• v.33 no.6
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• pp.245-251
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• 2022

We have developed a multi-channel fiber laser for tiled laser beam combining and a laser output array system for multi-beam alignment. The fiber laser is a master oscillator power amplifier configuration that has a common seed, a preamplifier, and a 7-channel amplifier. The output power of each channel is more than 10 W. The laser output array system is a packed cylindrical configuration for a high fill-factor, and it has capabilities for collimation and tilt control with built-in PZT. Multi-beam alignment to a target is successfully implemented using PZT controlled with a stochastic parallel gradient descent (SPGD) algorithm.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.15 no.2
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• pp.81-94
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• 2005

Recently, wireless LAN circumstance is being widely deployed in Public spots. Many People use Portable equipments such as PDA and laptop computer for multimedia applications, and also demand of mobility support is increasing. However, handoff latency is inevitably occurred between both APs when clients move from one AP to another. To reduce handoff latency. in this paper, we suggest WFH(Weighted Frequent Handoff) using effective data structure. WFH improves cache hit ratio using a new cache replacement algorithm considering the movement pattern of users. It also reduces unessential duplicate traffics. Our algorithm uses FHR(Frequent Handoff Region) that can change pre-authentication lesion according to QoS based user level, movement Pattern and Neighbor Graph that dynamically captures network movement topology.

• Journal of Digital Convergence
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• v.19 no.6
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• pp.73-83
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• 2021

This study identified the factors that influence the problem solving intention of students who completed the action learning-based creativity programs based on the theory of reasoned action, and examined the influence relationship between these factors. As a result of the study, first, subjective norms of problem solving had a positive effect on problem solving intention, and second, attitude toward problem solving had a significant effect on problem solving intention. Third, it was found that students who had experience of participating in a patent education program applying the action learning methodology had a positive effect on the relationship between their attitude toward problem solving and their intention to solve the problem. These findings confirmed that in order to enhance the problem-solving intention, which is the basis for creativity of university students, it is important to spread the positive value of problem-solving within the university and to give students a positive attitude toward problem solving.

• Journal of IKEEE
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• v.24 no.4
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• pp.1050-1057
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• 2020

Immersive 360-degree media has a problem of slowing down the video recognition speed when the video is processed by the conventional method using a variety of rendering methods, and the video size becomes larger with higher quality and extra-large volume than the existing video. In addition, in most cases, only one scene is captured by fixing the camera in a specific place due to the characteristics of the immersive 360-degree media, it is not necessary to extract feature information from all scenes. In this paper, we propose a reference frame selection method for immersive 360-degree media and describe its application process to copyright protection technology. In the proposed method, three pre-processing processes such as frame extraction of immersive 360 media, frame downsizing, and spherical form rendering are performed. In the rendering process, the video is divided into 16 frames and captured. In the central part where there is much object information, an object is extracted using an RGB vector per pixel and deep learning, and a reference frame is selected using object feature information.

• Design & Manufacturing
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• v.15 no.1
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• pp.57-65
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• 2021

Pump cap is a product that is widely used due to its ease of use and simple operation. These pump caps are applied to heterogeneous functional cosmetics and are being developed as dual pump caps. However, the conventional dual pump cap has a problem in that it is inconvenient to use and leakage occurs. In addition, it is formed of a plurality of materials, and there is a problem that is difficult to recycle. Lately, since the problem of environmental pollution is getting serious, the dual pump cap, which is difficult to recycle, cannot be used. Currently, eco-friendliness has been considered in Korea, and there are no dual pump cap containers with excellent sealing performance. Therefore, in this study, a dual pump cap container made of eco-friendly material was designed. In addition, finite element analysis was performed to verify the design feasibility of the product.

• The Journal of the Korea Contents Association
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• v.21 no.3
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• pp.410-418
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• 2021

In a program that runs an engineering education certification, program outcomes refer to the knowledge, skills, and attitudes a student must have until graduation. In general, capstone design is used as a tool for evaluating program outcomes. This paper applies the intraclass correlation coefficient (ICC) to measure the raters' reliability in assessing program outcomes. Several raters evaluate program outcomes, and the result is used to obtain the raters' ICC. ICC measures the reliability of ratings or measurements for clusters - data that has been collected as groups or sorted into groups. If the ICC is close to 1, it means that the reliability among the raters is high. We evaluated the proposed method's usefulness through case analysis. As a method for assessing an evaluation tool's objectivity, multiple raters measure the same evaluation tool. As a result, we measured the ICC values for all POs, and analyzed the cause for the low measured POs. We applied this method to evaluate program outcomes of the Department of Computer Engineering in the past two years. As a result, we derived guidelines for improvement and program outcomes.

• The Journal of the Convergence on Culture Technology
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• v.8 no.1
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• pp.121-129
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• 2022

This study explored effective teaching-learning activities under the hybrid teaching model combining flipped learning, direct instruction, cooperative learning and distance learning. Subjects were 99 college students enrolled in 2 teacher preparation courses. Students evaluated effectiveness of 22 teaching-learning activities according to Likert scale at the end of the semester. As a result, all 22 teaching learning activities were considered effective more or less. They facilitated motivation, comprehension, participation, thinking, and led to mastery of the task. ② Activities scored low were 'questioning and answering at the beginning of online class', 'open book test'. ③ Hybrid teaching model was favored over traditional instruction. Open ended responses were consistent with the ones in the questionnaire. This research supports the notion that key teaching models to be combined for successful flipped learning in college setting are direct instruction and cooperative learning. Furthermore, effective and ineffective teaching strategies for flipped learning were found.

• Journal of Korean Dental Hygiene Science
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• v.4 no.2
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• pp.77-88
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• 2021

Background: In this study, the Capstone Design was applied to the clinical dental hygiene course of the Department of Dental Hygiene, and its effect was confirmed by qualitatively evaluating the students' reflection on the capstone design class experience. Methods: This study was conducted for the "Clinical Dental Hygiene and Practice III" course, in which third year students develop the ability to judge and plan dental hygiene based on problem-solving ability and critical thinking. By applying the Capstone Design within the core curriculum of the class, the students analyzed problems based on their major knowledge of dental hygiene in order to improve their ability to manipulate periodontal instruments, and focusedon the process of developing the contents of periodontal instruments by using them. Results: The application of Capstone Design on clinical dental hygiene and practice III classes increased students' active class participation, and through the problem-solving process, students' learning and confidence improved. Conclusion: The Capstone Design can be viewed as a teaching method that promotes the participation of students in the dental hygiene department and can effectively help their learning and confidence through a problem-solving process.

• Journal of Engineering Education Research
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• v.25 no.5
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• pp.85-93
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• 2022

Capstone Design, a project-based learning technique, is the most important curriculum that clarifying major knowledge and cultivating the ability to apply through the process of solving problems in the industrial field centered on the student project team. Accordingly, various and extensive studies are being conducted for the successful implementation of capstone design courses. Unlike previous studies, this study aimed to quantitatively analyze the opinions that recorded the experiences and feelings of students who performed capstone design, and used text mining methodologies such as frequency analysis, correlation analysis, topic modeling, and sentiment analysis. As a result of examining the overall opinions of the latter period through frequency analysis and correlation analysis, there was a difference between the languages used by the students in the opinions according to gender and project results. Through topic modeling analysis, 'topic selection' and 'the relationship between team members' showed an increase in occupancy or high occupancy, and topics such as 'presentation', 'leadership', and 'feeling what they felt' showed a tendency to decreasing occupancy. Lastly, sentiment analysis has found that female students showed more neutral emotions than male students, and the passed group showed more negative emotions than the non-passed group and less neutral emotions. Based on these findings, students' practical recognition of the curriculum was considered and implications for the improvement of capstone design were presented.

• The Journal of the Korea Contents Association
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• v.21 no.7
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• pp.448-458
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• 2021

As the fourth industrial revolution accelerates, universities have made great efforts to develop and reform creative convergence courses for improving the students' creative convergence capabilities. Although various subjects such as "Capstone" and "Design Thinking" to the improvement of students' creative convergence competences, many courses focus on creativity education in the direction of creating new products or outputs such as engineering, design, and art, so there is still a lack of systematic education and subjects on creative convergence capabilities from a humanities and sociological perspective. In order to overcome their limitations of creative courses, "H" University developed a 'Imaginative Innovators' class with the purpose of solving creative problems on social issues related to sciences, culture, politics, economics, and so on. In this study, we introduced the purpose, methodology, students' best practices etc. of the "Imaginative innovator" course. In addition, we discussed the limitations and complements as well as the advantages and possibilities of the course. These findings are expected to contribute to the development and expansion of creativity education.