• Current Optics and Photonics
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• v.3 no.1
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• pp.16-21
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• 2019

We present a broad-bandwidth comb-spacing-swept source (CSWS) based on a differential polarization delay line (DPDL) for interferometric three-dimensional (3D) imaging. The comb spacing of the CSWS is repeatedly swept by the tunable DPDL in the multiwavelength source to provide depth-scanning optical coherence tomography (OCT). As the polarization differential delay of the DPDL is tuned from 5 to 15 ps, the comb spacing along the wavelength continuously varies from 1.6 to 0.53 nm, respectively. The wavelength range of various semiconductor optical amplifiers and the cavity feedback ratio of the tunable fiber coupler are experimentally selected to obtain optimal conditions for a broader 3-dB bandwidth of the multiwavelength spectrum and thus provide a higher axial resolution of $35{\mu}m$ in interferometric OCT imaging. The proposed CSWS-OCT has a simple imaging interferometer configuration without reference-path scanning and a simple imaging process without the complex Fourier transform. 3D surface images of a via-hole structure on a printed circuit board and the top surface of a coin were acquired.

• Nuclear Engineering and Technology
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• v.51 no.5
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• pp.1195-1208
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• 2019

This paper introduces a new two-step procedure for PWR depletion analyses. This procedure adopts the albedo-corrected parameterized equivalence constants (APEC) method to correct the lattice-based raw cross sections (XSs) and discontinuity factors (DFs) by accounting for neutron leakage. The intrinsic limitations of the conventional two-step methods are discussed by analyzing a 2-dimensional SMR with the commercial DeCART2D/MASTER code system. For a full-scope development of the APEC correction, the MASTER nodal code was modified so that the group constants can be corrected in the middle of a microscopic core depletion. The basic APEC methodology is described and color-set problems are defined to determine the APEC functions for burnup-dependent XS and DF corrections. Then the new two-step method was applied to depletion analyses of the SMR without thermal feedback, and its validity was evaluated in terms of being able to predict accurately the reactor eigenvalue and nodal power profile. In addition, four variants of the original SMR core were also analyzed for a further evaluation of the APEC-assisted depletion. In this work, several combinations of the burnup-dependent and -independent XS and DF corrections were also considered. The results show that the APEC method could enhance the nodal equivalence significantly with inexpensive additional costs.

• Safety and Health at Work
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• v.9 no.4
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• pp.427-433
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• 2018

Background: The purpose of this study was to identify the influence of workers' perceived workload, accident experiences, supervisors' safety leadership, and an organization's safety climate on the cognitive and emotional risk perception. Methods: Six hundred and twenty employees in a variety of manufacturing organizations were asked to complete to a questionnaire. Among them, a total of 376 employees provided valid data for analysis. To test the hypothesis, correlation analysis and hierarchical regression analysis were used. Statistical analyses were conducted using IBM SPSS program, version 23. Results: The results indicated that workload and accident experiences have a positive influence and safety leadership and safety climate have a negative influence on the cognitive and emotional risk perception. Workload, safety leadership, and the safety climate influence perceived risk more than accident experience, especially for the emotional risk perception. Conclusion: These results indicated that multilevel factors (organization, group, and individual) play a critical role in predicting individual risk perceptions. Based on these results, therefore, to reduce risk perception related with unsafe behaviors and accidents, organizations need to conduct a variety of safety programs that enhance their safety climate beyond simple safety-related education and training. Simultaneously, it needs to seek ways to promote supervisors' safety leadership behaviors (e.g., site visits, feedback, safety communication, etc.). In addition, it is necessary to adjust work speed and amount and allocate task considering employees' skill and ability to reduce the workload for reducing risk perception.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.2
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• pp.59-71
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• 2019

This study was conducted to prioritize land purchase in Hwapocheon wetland protection area by reflecting the conservation value of wetlands considering HSI(Habitat Suitability Index) for flagship species. As a result of this study, the flagship species, Oriental White Stork and Been Goose, which can represent the Hwapocheon wetland protection area, were selected through selection criteria and expert feedback. Based on the habitat requirements of the selected flagship species, SI(Suitability Index) for the flagship species was reviewed and the conservation value of wetlands was assessed. The conservation value of the wetlands was divided into five grades from very high to very low. The areas with high conservation value were mainly distributed around wetlands and waters in upstream and downstream of Hwapocheon wetland protection area. The land purchase priorities were divided into five grades by overlapping the thematic maps of the conservation value of wetlands, the economics, and the urgency of restoration. The arable lands which can disrupt wetland ecosystems are analyzed as priority areas where priority purchasing is required. Relatively well-preserved wetlands and areas have low land purchase priorities. This study is meaningful in that biodiversity is considered in land purchase priorities.

• Journal of Korean Physical Therapy Science
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• v.28 no.3
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• pp.1-10
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• 2021

Background: The purpose of this study is to investigate the effect of the online team project based learning on problem-solving, cooperative self-efficacy, and cooperative self-regulation of college students. Design: Single group pre-post design. Methods: The online team project based learning was conducted for a total of 92 college students for 8 weeks. A survey was conducted on problem-solving ability, cooperative self-efficacy, and cooperative self-regulation. In the online team project-based class, two projects were performed. It consists of video lectures and real-time video conferencing. Through the real-time video conference, the project was carried out based on discussion among learners and feedback was provided. Results: There was a significant difference in the change in problem-solving ability compared to before learning (p<0.05). As a result of the evaluation of cooperative self-efficacy, there was a significant difference (p<0.05). There was a significant differences in cooperative self-regulation compared to before learning (p<0.05). Conclusion: The online team project-based learning are effective in improving learners' problem-solving ability, cooperative self-efficacy, and cooperative self-regulation.

• Nuclear Engineering and Technology
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• v.54 no.7
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• pp.2670-2689
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• 2022

STREAM - a lattice transport calculation code with method of characteristics for the purpose of light water reactor analysis - has been developed by the Computational Reactor Physics and Experiment laboratory (CORE) of the Ulsan National Institute of Science and Technology (UNIST). Recently, efforts have been taken to develop a photon module in STREAM to assess photon heating and the influence of gamma photon transport on power distributions, as only neutron transport was considered in previous STREAM versions. A multi-group photon library is produced for STREAM based on the ENDF/B-VII.1 library with the use of the library-processing code NJOY. The developed photon solver for the computation of 2D and 3D distributions of photon flux and energy deposition is based on the method of characteristics like the neutron solver. The photon library and photon module produced and implemented for STREAM are verified on VERA pin and assembly problems by comparison with the Monte Carlo code MCS - also developed at UNIST. A short analysis of the impact of photon transport during depletion and thermal hydraulics feedback is presented for a 2D core also from the VERA benchmark.

• International journal of advanced smart convergence
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• v.11 no.2
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• pp.118-127
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• 2022

Barrage language is a new media language based on Internet video. It is a representative expression of the Internet environment regardless of its format and content. As a unique movie viewing characteristic provided by the barrage function, the timeliness of feedback, entertainment, and interactivity of the content are excellent. Characteristic. Barrage language itself is closely related not only to the value of linguistic research, but also to the spread of the Internet in the Internet environment. Based on the current situation of Chinese video sites, this thesis explores how Barrage is an organic cycle of culture and consumption in a specific platform and group, and analyzes its propagation methods and effects. By analyzing the characteristics of content production patterns unique to the barrage culture, implications and reference values for production activities of other cultures, the effect of popularization on viewers and the production and consumption of the 'barrage' culture of the industry is studied, and furthermore, the 'barrage' culture is It was designed to be a reference for the development of the platform, internet culture, and animation industry culture.

• International journal of advanced smart convergence
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• v.11 no.2
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• pp.194-204
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• 2022

This study is a one-group pretest-posttest design to evaluate the effect of problem-based learning (PBL) for patient safety on self-leadership, patient safety competencies, and reflective thinking of nursing students. The research was conducted from March 2 to April 15, 2022, in which 57 nursing students participated. PBL for patient safety was examined in a total of 8 sessions in the order of motivation, problem identification, task performance planning, problem-solving methods, summary and solution, presentation, and evaluation. The following topics of patient safety were selected for each team: nursing records, high-alert medication, medication error and intravenous fluid regulation, blood transfusion care, fall, bedsore, infection control, and pain management. We provided feedback on the learning process and outcomes of nursing students. According to the results, self-leadership showed a statistically significant improvement in self-expectations (t=2.60, p=0.01), goal setting (t=2.84, p<0.01), self-reward (t=3.32, p<0.01), and self-criticism (t=2.32, p=0.02). Patient safety competencies showed a statistically significant improvement in patient safety knowledge (t=13.05, p<0.001) and patient safety skills (t=4.87, p<0.001) but not in reflective thinking. The results prove that PBL for patient safety is an effective teaching-learning strategy to improve self-leadership and patient safety competencies. Future studies must develop and validate specific and long-term teaching-learning methods to improve reflective thinking.

• International Journal of Advanced Culture Technology
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• v.11 no.3
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• pp.302-309
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• 2023

This study aimed to develop a VR-based digital therapeutic intervention for the diagnosis and treatment of ADHD. The research combined medical data with virtual reality technology to develop an algorithm for ADHD diagnostic scales and implemented a VR-based digital therapeutic platform using a head-mounted display (HMD). This platform can be used for the diagnosis and treatment of ADHD in children and adolescents. Additionally, we four VR games were developed, including archery timing, Antarctic exploration, grocery shopping, and rhythm-based drumming(RBD), incorporating various psychiatric treatment techniques based on cognitive-behavioral therapy(CBT). To evaluate the usability of this digital therapeutic intervention, a group of experts specialized in counseling psychology participated in the study. The evaluations received highly positive feedback regarding the ability to access the system menu while wearing the HMD, the consistency of terminology used in menus and icons, the usage of actual size for 3D graphic elements, and the support for shortcut key functionality. The assessments also indicated that the games could improve attention, working memory, and impulse control, suggesting potential therapeutic effects for ADHD. This intervention could provide a daily treatment method for families experiencing financial constraints that limit hospital-based therapies, thereby reducing the burden.

• East Asian mathematical journal
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• v.39 no.4
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• pp.455-478
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• 2023

Expectations and interests in blended learning are increasing as universities respond to the educational flow of transition to e-lernring. This study tried to explore and understand the meaning of and the properties of blended instruction. In addition, through the literature review, this study was to find out how bleanded learning affected in teaching and learning situation. Particularly, it was to find out students' preference to the type of blended instruction. Those types are the mixed of or the unique of class instruction(off line), on line, and recorded instruction. To investigate learners' preference to the type of the instruction and also the reason of the preference, in this study, the 27 undergraduate students of the fourth grade in the major of mathematics education in the C university located in G area. By the result, most students preferred the mixed type of instruction involving off line and recorded instruction. The reason is that they could attend to the class while participating in the group activity positively and understand the content through the communication in depth and the instructor's feedback. Because of this reason, they did not prefer to the only one type insturction such as the recorded type.