• Structural Engineering and Mechanics
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• v.74 no.1
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• pp.129-143
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• 2020

This study proposes a new shape memory alloy-tuned mass damper (SMA-TMD) and investigates the effectiveness of this damper in reducing and controlling the vibrations of a transmission tower-line system under various seismic excitations. Based on a practical transmission line system and considering the geometric nonlinearity of this system, the finite element (FE) software ANSYS is used to create an FE model of the transmission tower-line system and simulate the proposed SMA-TMD. Additionally, the parameters of the SMA springs are optimized. The effectiveness of a conventional TMD and the proposed SMA-TMD in reducing and controlling the vibrations of the transmission tower-line system under seismic excitations is investigated. Moreover, the effects of the ground motion intensity and frequency ratio on the reduction ratio (η) of the SMA-TMD are studied. The vibration reduction effect of the SMA-TMD under various seismic excitations is superior to that of the conventional TMD. Changes in the ground motion intensity and frequency ratio have a significant impact on the η of the SMA-TMD. As the ground motion intensity and frequency ratio increase, the η values of the SMA-TMD first increase and then decrease. Studying the vibration reduction effects of the SMA-TMD can provide a reference for the practical engineering application of this damper.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.2
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• pp.422-429
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• 2015

The purpose of this study is the improvement of the existing trolling hauler, which has only one wheel to wind a main line, for saving man power around the coast of Jeju island. The trolling hauler manufactured for a test performance consisted of the wheel part of a main line and the roller part of a leader line including labor-saving devices comprised of a friction clutch, a fastener and springs. Even though this existing electric hauler system is convenient to control the wheel speed and the winding direction, it is apt to cost high and to corrode quickly at sea. Therefore, to remove these negative elements and to operate rollers for hoisting a leader line of the trolling, hydraulic motors were used separately. As a result, according to using of labor-saving devices, the towing tension occurred in operating in fishing ground could be selected moderately without breaking of lines and the operating efficiency of the trolling hauler was verified.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.6
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• pp.870-875
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• 2013

After introducing diagnosis equipment power failure prevention activities for distribution system have become more active. To do facility diagnosis and maintenance work more efficiently we need to evaluate reliability for the system and should determine the priority line with appropriate criteria. Thus, to calculate risk factor for the power distribution line that are composed of many component facilities its historical failure events for the last 5 years are collected and analysed. The failure statics show that more than 60% of various failures are related to environment factors randomly and about 20% of the failures are refer to the aging. As a strategic evaluation system reflecting these environmental influence is needed, a system on the basis of the probabilistic approach related statical variables in terms of failure rate and failure probability of electrical components is proposed. The figures for the evaluation are derived from the field failure DB. With adopting Bayesian rule we can calculate easily about conditional probability query. The proposed evaluation system is demonstrated with model system and the calculated indices representing the properties of the model line are discussed.

• Journal of Korea Multimedia Society
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• v.8 no.3
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• pp.389-397
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• 2005

In this paper, we study the synchronization method of animated simulations and VRs for on-line virtual reality education system. To build the data of animated simulations and synchronization modules of VRML content, the media-synchronizing technology, HTML + TIME and scripts are used. The VRML control module ismade into Java applet using the Java EAI provided for the web and the interface for VRML contents. To control the animation of VRML contents, the node information is extracted, and an animation production template capable of controlling animation in inter-connection with VRML content is made. With evaluation of the animation control performance, processing speed, synchronization performance between media in the system built, more improved results are obtained. We would like to suggest a education system with easy system construction and various multi-medium applicability by realizing HTML + TIME media synchronization and VRML web 3D virtual reality creation techniques, and animated images and 3D animation controls according to time using Java through this study.

• 한국정보교육학회:학술대회논문집
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• 2011.01a
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• pp.227-232
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• 2011

Individualized instruction only in the off-line classroom is not enough because elementary school students have various levels and tendencies. In recent years there are a lot of efforts to use online learning, and they are valuable. But the current online learning management systems are not utilized effectively in the elementary school. So this study suggests utilization plan of online learning management system through Moodle which can present and perform both learning objectives and learning contents for individualized instruction in elementary schools.

• The KIPS Transactions:PartA
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• v.12A no.2 s.92
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• pp.181-190
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• 2005

The development of web-based distance education surroundings is steadily achieving. However the studying on the learning effect of learners is still weak against development of educational media itself. At present, most of the distance education system is showing limits in the evaluation of the learning effect because the teaming evaluation depends on mid or final-term exams by on-line or off-line. There is a strong point that the distance education is free from space and time. One of present weak points is limitation of evaluating learner's attitude which can estimate learning effects. Earnest teaming attitude at distance education is important factor for improving the learning effects. In this paper, we propose a model for improving the teaming effects by forcing real-time evaluation and returning feedback to learners at the cyber lectures. The developed experimental system is verified its possibilities.

• Korean Medical Education Review
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• v.15 no.2
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• pp.69-74
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• 2013

This study aimed to review the expected changes in the medical educational environment and to evaluate approaches to coping with the abolition of the postgraduate intern training system. It is expected that after the intern training system is dismantled, postgraduate medical students will be deprived of the opportunity to practice opportunity for clinical practice and to inquire into their medical specialization. Therefore, major improvements in the clinical education curriculum must be made so that students can do so through the clinical education program. Offering students the opportunity to perform clinical practice through the clinical education program might require a revision in the laws and regulations on clinical education as well as the standardization of the clinical education curriculum in line with international practices. Reform measures to provide students the opportunity to inquire their specializations might be the introduction of a medical curriculum containing diverse fields and the establishment of a matching program to assign medical students to their residency programs after medical school. Finally, the fact that the basic concern of postgraduate medical education is the cultivation of primary care physicians must not be forgotten even after the dismantling of the postgraduate intern training system.

• PNF and Movement
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• v.11 no.2
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• pp.77-85
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• 2013

Purpose : The purpose of this study is to investigate the effects school business hospital-based integrated health education on learning transfer factor and level. Methods : This study conducted a questionnaire survey of 60 students at D college using metastatic diagnostic tool who took the integrated health education curriculum, statistical analysis utilized the SPSS 17.0 for window version. Results : On comparison of the details 5 clauses, 29 questions using LTSI, this study found that the integrated health education based on the school business hospital is effective for learning transfer. Conclusion : What the integrated health education based on clinic practice system at D college to overcome the limitations of health and medical line is effective for learning transfer and it will be useful to cultivate professional.

• Journal of Engineering Education Research
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• v.8 no.4
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• pp.5-19
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• 2005

Computer based teaming system has considerable influence upon teaching technique and teaming efficiency. It is possible to make a learner-oriented teaching in the online learning system. In this case, it can provide easily and immediately learner with various information that relate to class status, for example, attendance, examination score and so on. In the case of conventional off-line education, however, it is inefficient to provide the information of class status for learners compared with on-line system. In this paper, we propose a monitoring system of class status which can provide various information of teaming status for learners, instructors and advisors. It is useful to advise student's course work and job. The main purpose of this system is to prepare a monitoring system of class status on a web based e-class system. It achieves self-monitoring systems which provide a feedback data as a result of class for students.

• Journal of the Korea Safety Management & Science
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• v.10 no.1
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• pp.67-73
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• 2008

National Education Information System (NEIS) is an ambitious reform project that can improve the competitiveness and performance of education field and to link administrational work of between schools and their senior administration offices via internet. NEIS is introduced to lighten the teachers' overburden, to standardize the work process and to bring better quality education to each classroom and make it possible for those involved in education to resolve any related educational problem on line. This paper aims to construct a hierarchy model consisting of key factors such as technological and administrative factors for the effective use of NEIS and to evaluate the relative importance among key factors using fuzzy AHP technique included fuzzy concepts. Eventually, the analysis results can be utilized to develop the future improvement strategy of NEIS and to satisfy the users.