• Journal of the Society of Naval Architects of Korea
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• v.52 no.4
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• pp.323-329
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• 2015

For the design guide of a vessel operating in cold region, numerical analysis was carried out to evaluate the ice class louver which installed the heating cables by using ANSYS 13.0 CFX. The numerical analysis was performed by considering Unsteady Reynolds Averaged Navier Stokes (RANS) equation. This study based on the experimental results of ‘The Cryogenic Performance Evaluation for the Excellent De-icing Ice Class Louver’ in KRISO. For validation of the numerical analysis results, the cold chamber experimental data measured by the heat sensors in certain location of the ice class louver was used. The external environmental temperature which varies from 0℃ to –30℃ was considered in numerical analysis. Also the design guide for optimum de-icing presented through heating cable power capacity(33 W/m, 45 W/m, 66 W/m), location of the heating cable(front, center, behind on the blade) and relative velocity(1 m/s, 4 m/s, 7 m/s).

• The korean journal of orthodontics
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• v.45 no.6
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• pp.322-332
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• 2015

A 12-year-old girl was referred to our clinic for evaluation of an unaesthetic dental appearance. All permanent teeth were erupted, while the deciduous maxillary right canine was retained. Cone-beam computed tomography revealed a complete transposition of the maxillary left canine and first premolar involving both the crowns and the roots. Initial cephalometric analysis showed a skeletal Class III pattern, with a slight maxillary retrusion and a compensated proclination of the upper incisors. The patient's teeth were considered to be in the correct position; therefore, we decided to attempt treatment by correcting the transposition and using only orthodontic compensation of the skeletal Class III malocclusion. After 25 months of active orthodontic treatment, the patient had a Class I molar and canine relationship on both sides, with ideal overbite and overjet values. Her profile was improved, her lips were competent, and cephalometric evaluation showed acceptable maxillary and mandibular incisor inclinations. The final panoramic radiograph showed that good root parallelism was achieved. Two-year follow-up intraoral photography showed stable results.

• Journal of the Korea Society of Computer and Information
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• v.24 no.4
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• pp.195-204
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• 2019

In this paper, we propose the way to solve the problems of current college of education at university that they are running a curriculum that is insufficient for immediate application to the school. So, we analyzed the application of capstone design which is proven to be effective in various fields, and constructed a curriculum for the development of educational materials to improve the teacher's qualification in the college of education and applied them to the preliminary informatics teachers. As a result, we confirmed that the development class of educational materials based on capstone design is positive for the change of awareness about informatics teacher's qualification, and also confirmed that the students' satisfaction level about class is higher. Based on the results, we discussed the effects of applying capstone design to the college of education. The conclusions are as follows: First, it helps students to improve the teacher's qualification. Second, it is a curriculum that can fill the shortage of student teaching. Third, the curriculum is an effective curriculum for the recognition of the student who is in charge of evaluation, and the teacher who is in charge of the evaluation. Fourth, Capstone design information textbook study class is a method of greatly improving class satisfaction compared to lecture class.

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.672-680
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• 2011

The purpose of this study has been carried to develop a criterion for the selection of evaluation factors on Forest Carbon Cycle Community(F.C.C.C) based on the result of survey of 96 participants who were operation managers on mountain eco village(31), relevant experts(33), and officers of local government(32). For analysis of the results of survey, DHP(Delphi Hierarchy Process) method was used which is a combination of Delphi method and AHP(Analytic Hierarchy Process) method. The key factors on selection of a suitable area to launch F.C.C.C. project of Korea Forest Service was selected under three hierarchical classes. Class 1 comprises 3 indices(Physical resource index, Human resource index, Vision index), and Class 2 which contains 10 indices (Existing resource, Surroundings resource, Forest biomass resource, Humanities Social quality, Local resident participation, Leader's ability, External support, Planning of operation, Capability of operation, and Effect of operation). Class 3 is sub-level class of class which possess 38 indices. From the results of analysis, Consistency Index(C.I) of each index in the 3 classes was used as evaluation factor. In Class 1, index 'human resources' showed highest Consistency Index(0.454). In Class 2, index 'forest biomass resources' was the highest Consistency Index(0.376) in 'physical resources' of Class 1, index 'leader's ability' was the highest Consistency Index(0.326) in 'human resources' of Class 1, and index 'planning of operation' was the highest Consistency Index(0.346) in 'vision' of Class 1. In Class 3, relative importance of 38 index including 'Joint ownership land security(C.I.-0.266)' was evaluated. Based on the result of this study, a criterion for the selection of evaluation factors for F.C.C.C was developed and the evaluation criterion is expected to be use to select of a suitable area to launch F.C.C.C. project since 2011.

• Journal of the Ergonomics Society of Korea
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• v.33 no.3
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• pp.215-227
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• 2014

Objective: The purpose of this study was to evaluate Korea's Honam express train's first- and second-class seat discomfort by using pressure measurement, subjective discomfort rating, and physical compatibility. Background: Over the years, the demand for an express train service is continually increasing. A comfortable ride is important to achieving passenger satisfaction. A train seat plays a significant role in fulfilling passenger seating comfort. With this in view, a field survey and pressure measurements were performed on the selected train seat. Method: The pressure ratio at the body-seat interface (thigh and buttock regions) was measured by the pressure mat system. The interface pressure ratio was calculated and compared. The subjective discomfort rating scale was used to evaluate the subjects' overall feeling. The dimensions of train seats were analysed according to the anthropometric and demographic characteristics of the population data from Size Korea. Results: The results highlighted that the interface pressure ratio was greater while participants sat on the second-class seat than the first-class seat in the left- and right-side thigh regions. Also the pressure ratio was greater for the participants in the 1st~25th percentile height groups (149.8~160.8cm). The subjects rated higher discomfort for the second-class seat than the first-class seat. The physical compatibility results showed that the second-class seat's breadth was inadequate for the 95th and 99th percentile male. Conclusion: Overall, interface pressure measurement, subjective discomfort score and physical compatibility results showed that the second-class seat was more uncomfortable for the passengers than the first-class seat. Application: The adopted methodologies could be used to measure the seating comfort of the train seats.

• Journal of the Korean Data and Information Science Society
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• v.23 no.6
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• pp.1137-1144
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• 2012

Many universities stress gradually the importance of english-medium class in order to improve the international competitiveness and the internationalization of the university. In this paper, we compare english-medium class with korean class using course evaluation score. Also we analyze the factors that affect the effectiveness of the course evaluation score of english-medium class. First, logistic regression analysis is used to examine the main effects of subjects and individual characteristics. Also, decision tree analysis is used to examine the interaction effects for subjects and individual characteristics. The results of this paper are as follows. Grade, department category, class size, GPA and screening method affect the effectiveness of english-medium class. The highest effectiveness group of english-medium class is that grade is freshmen and department category is humanity. Also the group of the second highest effectiveness group is that grade is freshmen and department category is nature and art and GPA is high.

• Journal of the Korean Society of Earth Science Education
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• v.12 no.3
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• pp.239-251
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• 2019

The study aims to run a 'Process-based Evaluation' and find out its effectiveness in science classes for prospective elementary school teachers. The Process-based Evaluation performed in this study was performed during unit classes and scored when significance was recognized in the student's learning behavior. The conclusions based on the results of the study are as follows. First, students scored an average of 3.6 points on whether the process-oriented assessment conducted during class was appropriate as an assessment. Second, on the basis of the assessment presented by the students, the main positive content is "assessing the process, not the outcome", "contributing positively to class participation" and "promoting accident activities". Third, the negative contents of the assessment grounds presented by the students include 'lack of objectivity in evaluation methods and results', 'the individual tendencies of students are involved in evaluation results' and 'poor learning effects of the textbook knowledge'.

• English Language & Literature Teaching
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• v.12 no.4
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• pp.159-183
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• 2006

The purpose of this study is to investigate Korean primary school English teachers' beliefs on self-directed teaching and learning for facilitating student's self-directed learning. A survey was conducted, using 315 primary school teachers as participants. According to different school areas, sex, English teaching careers, and types of English teaching like classroom teachers or English specialist teachers, beliefs on teachers' self-directed teaching were studied based on class planning, class process, utilization of human resources, development and utilization of teaching materials and class evaluation. The results of this study are as follows: first, differences were not shown except class planning according to teachers from different school areas. Second, sex and beliefs of teachers' self-directed teaching had nothing in common. Third, differences were shown in class planning and class process, according to English teaching careers. Finally, according to types of English teaching, differences were shown in class process and development and utilization of teaching materials. The study suggests that it is necessary to conduct other studies for observing primary English classrooms focusing on teacher's self-directed decision-making.

• Journal of information and communication convergence engineering
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• v.6 no.2
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• pp.154-157
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• 2008

A class-E RF(Radio Frequency) power amplifier for wireless application is designed using standard CMOS technology. To drive the class-E power amplifier, a class-F RF power amplifier is used and the reliability characteristics are studied with a class-E load network. The reliability characteristic is improved when a finite-DC feed inductor is used instead of an RF choke with the load. After one year of operating, when the load is an RF choke the output current and voltage of the power amplifier decrease about 17% compared to initial values. But when the load is a finite DC-feed inductor the output current and voltage decrease 9.7%. The S-parameter such as input reflection coefficient(S11) and the forward transmission scattering parameter(S21) is simulated with the stress time. In a finite DC-feed inductor the characteristics of S-parameter are changed slightly compared to an RF-choke inductor. From the simulation results, the class-E power amplifier with a finite DC-feed inductor shows superior reliability characteristics compared to power amplifier using an RF choke.

• Journal of the Korean Institute of Educational Facilities
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• v.2 no.3
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• pp.31-38
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• 1995

The paper is to evaluate existing school building system with respect to students' comforts in the class room in Korea. This paper compared three styles of different school building system builted during last 20 years. Using statistical analysis, at first, the paper found that box-style structure is efficient for sustaining heat in the class room because it is compactly constructed. Secondly, air conditioning in the class room is important factor affected students' comforts in the summer time and for the smog occurring in the heating class room. Thirdly, we should compactly construct school building because the compactiveness of building components is important factor for student comforts. Fouthly, heating system in the class room should be changed. The system using gas or electricity insteded of coals should be introduced in the class room for the smog of the stove in winter time and for freshness in summer time.