• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.1
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• pp.101-111
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• 1993

Many processes such as machining, injection-moulding and metal-forming are usually operated by hydraulic servo-systems. The dynamic characteristics of these systems are complex and highly non-linear and are often subjected to the uncertain external disturbances associated with the processes. Consequently, the conventional approach to the controller design for these systems may not guarantee accurate tracking control performance. An effective neuro-fuzzy controller is proposed to realize an accurate hydraulic servo-system regardless of the uncertainties and the external disturbances. For this purpose, first, we develop a simplified fuzzy logic controller which have multidimensional and unsymmetric membership functions. Secondly, we develop a neural network which consists of the parameters of the fuzzy logic controller. It is show that the neural network has both learning capability and linguistic representation capability. The proposed controller was implemented on a hydraulic servo-system. Feedback error learning architecture is adopted which uses the feedback error directly without passing through the dynamics or inverse transfer function of the hydraulic servo-system to train the neuro-fuzzy controller. A series of simulations was performed for the position-tracking control of the system subjected to external disturbances. The results of simulations show that regardless of inherent non-linearities and disturbances, an accuracy tracking-control performance is obtained using the proposed neuro-fuzzy controller.

• Journal of The Korean Association of Information Education
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• v.3 no.2
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• pp.120-127
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• 2000

All possible efforts have been done to adapt to the information-oriented society throughout the whole area of education. Especially, it is strongly demanded that teachers should effectively apply information communication and disposal to all the educational activities of instruction-learning, students management, school affairs, and administrative affairs. In this thesis, we chose as educational contents the information technology which is necessary in an educational site to increase the capability of applying information of teachers and developed remote training materials. In addition, we developed measurement instruments to evaluate the capability of applying information of teachers and gave grades to them. Grading System of the Capability of Applying Information of Teachers will be a standard of the capability of applying information.

• The Journal of the Korea Contents Association
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• v.19 no.5
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• pp.389-403
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• 2019

This study has a purpose, that investigating influence of learning characteristic, lifelong learning participation motive, and wisdom that adult has at learning outcome and whether it has mediating effect of wisdom at influence that learning characteristic and lifelong learning participation motive have. For this, the subjects of the study was 425 adult learners from 20 to 69 years old who participated or are participating at Seoul, Incheon, and Gyeonggi-do. The results of this study are as in the following. At first, as a result of investigating relationship between learning characteristic, lifelong learning participation motive, wisdom, and learning outcome, the correlation coefficient of all variables appeared meaningfully. Second, as a result of investigating influence that learning characteristic, lifelong learning participation motive, and wisdom have in learning outcome, the most influential variable was learning value, the rest were cognitive capability, activity direction motive, learning direction motive and positive life attitude in this order. The third, as a result of investigating mediation effect of wisdom at influence that learning characteristic and lifelong learning participation motive have in learning outcome, Wisdom at the influence that learning characteristic have on learning outcome had completely mediated effect, and the wisdom at the influence that lifelong participation motive have on learning outcome had partially mediated effect. Thus, it was shown up that adult's learning characteristic and lifelong learning participation motive are able to increase effectively learning outcome by mediating wisdom. Therefore it is implying that it is essential to consider learning characteristic and lifelong learning participation motive in lifelong education field, and learning circumstance related with wisdom is important, as wisdom is important variable for increasing learning outcome.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.33 no.4
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• pp.130-137
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• 2010

This paper analyzes the main factors affecting user selection of a small-sum electronic payment system using survey data of 396 users. Several findings emerge. First, users consider three pillars and eight factors in adopting a new system : system features(stability, security, and flexibility), transaction cost(payment commission and settlement period), and financial capability of provider(stability of financial structure, risk management capability, and funding capability). Second, the stability of the financial structure of the system provider is the most important factor to user acceptance of a new e-payment system. Users tend to consider uncertainty risk more seriously than transaction cost. This reflects the reality that electronic payment system service industry has not fully fledged yet. Third, some moderating effects exist according to payment methods and business usages. As for payment methods, speedy settlement cycle for wired/wireless phone payment, system stability for credit card and account transfer payment, and security for advance payment means are crucial factors. As for business usages, the stability of financial structure for online game content, system stability for music and video content, proxy payment commission for e-learning content, flexibility of the payment system for digital adult content, and security for public services are decisive ones.

• Management & Information Systems Review
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• v.35 no.2
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• pp.45-66
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• 2016

Firms can make scale of economy and scope of economy by internalizing and using new advanced technology and knowledge from technology cooperation network, decrease risk and cost with partner firm of technology cooperation network, and increase market advantage of product & strengthen firms' position in the market. Due to the advantages of technology cooperation network, the related studies have focused on the positive effect of technology cooperation network. However, the related studies investigating the relationship between technology cooperation network and firm performance have only examined the role of technology cooperation network. Safeguarding mechanism, relationship learning, and relationship performance are categorized into the process of technology cooperation network, and this categorization is applied as resources, capability, and performance by resource based view. The empirical results are reported as belows. First, relationship specific investment and relationship capital positively affect on relationship learning as capability. Second, information sharing, common information understanding, and relationship specific memory development positively affect on long-term orientation, but information sharing has no impact on efficiency and effectiveness. Third, relationship specific investment positively affects on relationship capital and efficiency and effectiveness have positive effects on long-term orientation. Applying technology cooperation network in asymmetric technology dependency with resource based theory, this study suggested the importance of both safeguarding and relationship learning by investigating the relationship among safeguarding, relationship learning, and relationship performance. And it is worthy that this study investigated how firms' behavior change affects relationship performance in the relationship of technology cooperation partner.

• 전자공학회논문지 IE
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• v.46 no.3
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• pp.62-67
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• 2009

In this paper, ROC curves were designed by using Fuzzy Logic Systems. ROC curve is used for diagnostic evaluation and the person evaluating ROC curve is chosen as a first-level diagnostician. For rating diagnostic capability on ROC curve through learning, the chest X-ray image is used. The images used for making a diagnosis are X-ray film being both noise and signal. The result over diagnostic capability difference between the male and the female represented a man had better than a woman but that difference can be ignored.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.1
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• pp.300-314
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• 2016

The purpose of this study was to examine the effects of small-group discussion and panel discussion as teaching and learning methods on college students' competencies of communication, problem-solving and leadership in a general education course. Participants were 52 college students, and they participated in the 13-session lessons. The data from questionnaires collected before and/or after the experiment were analyzed using a paired t-test and percent. The results were as follows. First, each 'total' competency in communication, problem-solving and leadership was increased statistically significant after the experiment. Second, in subdomains of each key competency, 'directed communication' and 'understanding the perspective of others' in communication, and 'divergent thinking', 'decision-making' and 'assessment' subdomains in problem-solving, and all subdomains in leadership were increased statistically significant after the experiment. Based on the results and students' opinions about discussions, the education implications for small-group discussion and panel discussion were discussed.

• Proceedings of the KIEE Conference
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• 2002.11c
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• pp.193-196
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• 2002

This paper proposes the control problem of an inverted pendulum system based on Sugeno-Type of fuzzy logic. The universal approximating capability, learning ability, adaptation capability and disturbance rejection are collected in one control strategy. The proposed scheme does not require an accurate dynamic model and the joint acceleration measurement, yet it guarantees asymptotic trajectory tracking. Experimental results perform with an inverted pendulum to show the effectiveness of the approach.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1996.10a
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• pp.285-289
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• 1996

Fuzzy logic controllers have been shown better performance than conventional ones especially in highly nonlinear plants. These results are caused by the nonlinear fuzzy rules were not sufficient to cope with significant uncertainty of the plants and environment. Moreover, it is hard to make fuzzy rules consistent and complete. In this paper, we employed a predictive neural network to enhance the nonlinear inference capability. The predictive neural network generates predictive outputs of a controlled plant using the current and past outputs and current inputs. These predictive outputs are used in terms of fuzzy rules in fuzzy inferencing. From experiments, we found that the predictive term of fuzzy rules enhanced the inference capability of the controller. This predictive neural network can also help the controller cope with uncertainty of plants or environment by on-line learning.

• East Asian mathematical journal
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• v.37 no.4
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• pp.523-541
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• 2021

Education for the future society should emphasize the experience of sharing, coexisting, and solving problems in cooperation with each other in the community. Accordingly, in addition to the problem-solving capability, which is the ultimate goal of mathematics education, it is necessary to strengthen the capability to solve unstructured problems through collaboration. This study attempted to suggest that solving complex problems through collaboration is used in school classes or gifted education by introducing polymath that solves problems using collective intelligence. Accordingly, a target problem was set and an example of polymath in which community members exert each other's intelligence to solve the problem. In addition, by investigating the perceptions of students who have experienced polymath, positive aspects and improvements of polymath were suggested. Through this, this study can contribute to revitalization of mathematics teaching and learning methods using collective intelligence.