• Journal of IKEEE
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• v.3 no.2 s.5
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• pp.250-258
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• 1999

This paper presents a decentralized adaptive controller design for a Magnetically Levitated Fine Manipulator to follow the given trajectory as close as possible in spite of coupling effects between motion axes(degree of freedoms or subsystems). The present controller consists of two parts: the model reference controls based on known subsystems and the local adaptive controls. The former stabilizes the motion of the manipulator so as to follow that of the reference model. The latter reduces tracking errors due to coupling disturbances by adjusting the local gains to such levels that override interactions and assure the stability of the overall system. Through several experimental results, it has been shown that the decentralized adaptive control scheme has better tracking performances comparing to the PID controller case as well as good disturbance(coupling) rejection property.

• The Journal of the Convergence on Culture Technology
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• v.6 no.3
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• pp.443-448
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• 2020

In this study, field measurements were performed to analyze the effects of train types (AREX, AREX Express, KTX, KTX-Sancheon) and train speeds on the dynamic behavior of the direct fixation track structure on Yeongjong grand bridge by bridge type (truss bridge, suspension bridge). Based on field measurement results, the track impact factor and train running stability (coefficient of derailment, Rate of wheel load reduction, lateral displacement of rail head) are compared with domestic and foreign standards and regulations to influence the dynamic behavior of direct fixation track. As a result, the differences in the dynamic behavior of the direct fixation tracks by the type of bridges of Yeongjong bridge are not significant, but it was analyzed that these were more directly affected by the magnitude of the train load. Therefore, it is necessary to establish the reinforcement plan of the direct fixation track structure on Yeongjong grand bridge in consideration of the increase of the track impact factor and dynamic track force.

• The Journal of Korean Association of Computer Education
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• v.4 no.2
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• pp.1-11
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• 2001

The computer subject emphasizes practice centered teaching. The materials can be used in such practice teaching play a role as resources improving poor practice teaching environment. Web courseware can be used as teaching-learning materials causing motivation and interest to learners and enabling learning activity meeting students' level and requirement. So, we developed 15 web coursewares as teaching and learning materials for middle school Computer subject in this study. The design forms of web coursewares we developed are different each other. And then, lead teachers to develope teaching and learning materials originally and to apply them to teaching variously. In addition, the practice parts of web coursewares were made of form of sham learning appling procedural simulation skill. It enables individual practice of learners, so we expect improving one to many instruction environment somewhat.

• The Journal of Korean Association of Computer Education
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• v.4 no.2
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• pp.145-154
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• 2001

As it is shown that the Ministry of Education has asked teacher to use ICT (Information and Communication Technology) at least 10% of class time in core subjects of the 7th national curriculum, the ICT using education is being facilitated. In this point of view, current information subject curriculum can be criticized due to the lack of series and redundancy, less connectivity with ICT utilization in other subjects, limitation of training students to adapt rapidly changing world environment. Therefore, we analyze the England's ICT curriculum and derive the concrete objects for competence of students according to their ability, systematic connection with other subjects, class teaching methods based on activities. We insist on that information subject curriculum should focus on the development of learners' concrete competencies rather than learning of tools' functions.

• The Journal of Korean Association of Computer Education
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• v.20 no.4
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• pp.37-46
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• 2017

Since 2018, the level of informatics education that is mandatory in junior high schools depends on the subject matter expertise of Informatics & Computer teachers. The purpose of this study is to analyze whether secondary teacher training institutes provide curriculum that guarantees the subjectivity of Informatics & Computer teachers. In order to achieve the goal, this study first compares curriculum courses for educating Informatics & Computer teachers of Korea secondary teacher training institutes with subjects based on the content system of J07-CS, the informatics education in Japan. Second, we compare the basic subjects offered by the Ministry of Education with the vocational subjects. Third, we analyzed the basic subjects of each university. As a result of the study, the number of informatics-related courses opened by Korean secondary teacher training institutions was insufficient compared to the number of subjects in J07-CS. Even though the standard of comparison was limited to basic subjects, the content elements were insufficient, and the ratio of the basic subjects of each university was low. In order to achieve the goal of informatics education from 2018, it is urgent to improve the curriculum of secondary education teachers.

• Management & Information Systems Review
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• v.31 no.2
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• pp.1-20
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• 2012

The purpose of this study was to investigate the influence of leadership types and self-efficacy, job satisfaction on organizational performance. The hypotheses were suggested and data analyses were performed to verify these hypotheses. Data gathering were performed by self-administered questionnaires on the samples of 423 mechanical fields employees in Busan & kyongnam. The results of structural model exhibit that transformational leadership, transactional leadership was positively related to elf-efficacy. And it was also found that self-efficacy, job satisfaction was positively related to organizational performance. Expecially, it showed self-efficacy, job satisfaction as a mediator on the relationships between the leadership types and organizational performance.

• Journal of Digital Contents Society
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• v.13 no.3
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• pp.335-342
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• 2012

The purpose of the study was to develop a computer access assessment system for improving computer access of individuals with physical disabilities for the first time in Korea. Korea-Computer Access Assessment System (K-CAAS) presented in this article tests five user skills of aim, drag, menu, scan, and switch. Skill levels of the five test areas could be set as low, middle, and high according to individuals' characteristics. All tests have their default set in each level, and skill levels can be selected and controlled by the abilities and goals of a user. Tests could be selected for users' training and their results could be traced and shown. Therefore, the K-CAAS is a training program to improve computer access skills as well as an assessing program. It would help users with physical disabilities operate a computer by themselves as improving their computer access skills.

• Journal of Digital Contents Society
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• v.17 no.4
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• pp.295-305
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• 2016

The purpose of this study is to analyze the internal reputation factors that affect the job satisfaction by big data analysis in the social media for corporate reputation and verify the difference between large corporations and small-medium corporations for each factor of internal reputation. The result showed 'Salaries and Benefits' is a major factor that affects the job satisfaction for all research corporations, 'Senior Management' is a major factor for large corporations, and 'Salaries and Benefits' is a major factor for small-medium corporations. As for the difference factors of large corporations and small-medium corporations are 'Job Satisfaction', 'Salaries and Benefits', and 'Work-life Balance'. Unstructured data analysis shows some interesting features to be studied further.

• Journal of Digital Contents Society
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• v.19 no.9
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• pp.1759-1767
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• 2018

As our society is rapidly entering an aging society, interest in mobile health care services for disease prevention and health care for the elderly is increasing. To increase the usability of mobile healthcare services, UI design should be considered from an older person's perspective and a specific evaluation system is required to diagnose these UI usability levels. This study aimed to develop a UI usability evaluation area of mobile-healthcare application for the elderly. For this, we conducted a literature analysis to explore the comprehensive UI usability evaluation factors, and FGI for expert groups and user groups to derive UI usability evaluation areas and detailed evaluation factors. As a result, the usability evaluation areas for the elderly were divided into four areas 'design', 'contents', 'process', and 'system'. A total of 13 sub-factors and 32 detailed constructions have been derived.

• Journal of the Korean Magnetics Society
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• v.6 no.4
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• pp.264-271
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• 1996

A magnetically shielded room has been constructed for biomagnetic applications. The room has internal dimensions of $2\;m(length){\times}2\;m(width){\times}2.5\;m(height)$ and it consists of high permeability Mumetal and high conductivity alummum, utilizing ferromagnetic shielding and eddy current shielding. The de shielding factor around the center of the room is above 60 dB, and the ac shielding factors at 1 and 10 Hz are larger than 60 and 80 dB, respectively. The internal magnetic field noise at 1 Hz is $500\;fT/{\sqrt}Hz$ and at 10 Hz is $100\;fT/{\sqrt}Hz$, and the field gradient noise at 1 Hz is below $7\;fT/cm{\sqrt}Hz$. Successful measurements of cardiomagnetic fields usmg SQUID magnetometer and neuromagnetic fields using SQUID gradiometer have been done.