• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.430-432
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• 1993

In this paper, an algorithm for the fault diagnosis using simple FCM(Fuzzy Cognitive Map) is proposed FCMs which store uncertain causal knowledges are fuzzy signed graphs with feedback. The algorithm allows searching the origin of fault and the ways of propagating the abnormality throughout the process simply and has following characteristics. First, it can distinguish the cause of soft failure which can degenerate the process as well as hard failure. Second, it is proper for the processes which have difficulties to establish the exact quantative model. Finally, it has short amputation time in comparison with the fault tree or the other AI methods. The applicability of the proposed algorithm for the fault diagonosis to a tank or pipeline system is demonstrated

• Korean System Dynamics Review
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• v.17 no.3
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• pp.51-90
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• 2016

Learning is naturally embedded in organizational ongoing-processes and routines. Recent many research models of organizational failure ignore how failing masks breakdowns and recoveries of organization-embedded learning as a naturally occurring process. Organizational learning is the platform in tandem with base-modules of organization in this point. Organizations learn and unlearn while they acquire, discard, and forget organizational experiences or knowledges. These processes in public sector organizations are different from learning behaviors in private sector. This study expects to explore architectural components of learning organization in public sector, focusing on distinct characteristics of public organizations, and to implement learning model based on system thinking(system dynamic) approach.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.4
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• pp.66-73
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• 2005

A great deal of exhaust gas inside a combustion room goes out through exhaust pipe. But residual gas 'Blowby gas' enters the crankcase through a small gap between the piston and the cylinder wall. Here, if the blowby gas isn't vented, this causes many bad efffcts such as lubricant oil contamination, corrosion by that and crankcase explosion by rising pressure. So most automobiles are constituted with a PCV(Positive Crankcase Ventilation) system to prevent previous problems. PCV valve is the most important part in this ventilation system. When companies are manufacturing new cases, engineers are designing it depending on their experiments than theoretical knowledges. Much efforts and times are needed for new development. This study will show quantitative results to increase the possibilities for the optimal design.

• Proceedings of the Technology Innovation Conference
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• 2005.02a
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• pp.109-123
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• 2005

There has been great effect on development and usage of resources as well as technological development including everyday life pattern to maintain environmental sustainability, Also, It is tend to become negative for people's concern of nature ecosystem toward new technological developments because it is neither environmentally, nor naturally friendly. Therefore, our study is to implement expert education and research system which includes the trends and requests of our society with objectives as follows; First, Training industrial technology and policy maker who can understand and practice ecological ethics. Second, Educating people with expertise which can evaluate and complement the environmental friendliness about new industrial technologies. Third, Educating people who can develop technology which is environmentally friendly. Our new program requires various knowledges and balanced point of view. To this end, students are required to understand field of art and sciences including emerging eco-buddhism subject as well as field of state-of-the art environmental technologies such as recycling technology and clean production technology.

• Journal of Welding and Joining
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• v.20 no.1
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• pp.26-33
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• 2002

This study was undertaken to obtain the fundamental knowledges on the weld deflects and it's realtime monitoring method. The paper describes the results of high speed photography, acoustic emission (AE) detection and plasma light emission (LE) measurements during $CO_2$ laser welding of STS 304 stainless steel and A5083 aluminum alloy in different welding condition. The characteristic frequencies of plasma and keyhole fluctuations at different welding speed and shield gases were measured and compared with the results of Fourier analyses of temporal AE and LE spectra, and they had considerably good agreement with keyhole and plasma fluctuation. Namely, the low frequency peaks of AE and LE shifted to higher frequency range with the welding speed increase, and leer the argon shield gas it was higher than that in helium and nitrogen gases. The low frequencies dominating in fluctuation spectra of LE probably reflect keyhole opening instability. It is possible to monitor the weld bead deflects by analyzing the acoustic and/or plasma light emission signals.

• Journal of the Korean Society for Precision Engineering
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• v.7 no.2
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• pp.95-104
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• 1990

This paper descirbes some research of Computer-aided Design of multi-stage cold forging die of rotationally symmetric parts produced by the press or former. An approach to the system is based on knowledge based system. Knowledges for tool design are extracted from the plasticity theory, handbooks, relevent references and empirical know-how of experts in cold forging companies. The deveoped system is composed of three main modules such as die design module, punch design module, tool elements design module which are sued independently or in all. Using this system, design parameters (types of dies, geometric shapes and dimensions of dies, types of punches, geometric shapes and dimensions of punches, geometric shapes and dimensions of tool elements) in each operation are determined and the output is generated in graphic form. The develpoed system, aids designer, provides powerful capability for designing dies, punches and tool elements.

• Journal for History of Mathematics
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• v.16 no.1
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• pp.25-44
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• 2003

In this paper, we deal with the ‘dearithmetization’ of algebra. Historically, the origin of algebra comes from arithmetic. Also school algebra is related to arithmetic in general. However, we have many difficulties in teaching school algebra, and there is many problems for students to learn algebra from elementary arithmetic knowledges. This paper supposed that the solution of these problem may be founded in the ‘dearithmetization’ of algebra. And we supposed that the ‘dearithmetization’ of algebra may be developed by three historical achievements - the completion of symbolic algebra, the principle of permanence of form, and the expansion of number concepts. In order to justify these supposition, we investigate Peacock's ideas, i.e. ‘symbolic algebra’, ‘the principle of permanence of form’, and consider how the integer is introduced in modern mathematics. And we analyze various textbooks, and investigate the ‘dearithmetization’ of school algebra which has been progressed in the three fields - symbolic algebra, the principle of permanence of form, and the expansion of number concepts.

• Journal of Korean language education
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• v.25 no.1
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• pp.29-52
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• 2014

The purpose of this paper is to suggest a discourse analysis activity that can be used in the stage after performing tasks in task-based Korean speaking class and show its pedagogical advantages. A discourse analysis activity is an metadiscourse activity in which learners speak what they have spoken. By analyzing discourse and performing tasks again, learners can enhance their fluency and accuracy, make their knowledges in target language more stable and extend them, and develop problem solving skills. Consequently, this facilitates learners' acquisition of Korean language. This paper reviewed theoretical background of proposing discourse analysis activity, suggested the pedagogical advantages of the analysis, and examined discourse analysis activity in Korean speaking class. And it included the discourse sample of learners in actual class.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.1
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• pp.95-97
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• 2007

Our understanding on the plant's capability to acquire the nutrients from the soil under harsh circumstance, like unfavorably high pH, and the plant's capability to protect itself under very low soil pH, has been remarkably increased in the recent years. Having those knowledges, it seems not to be wise to abide to the traditional approach to deal the problems of acidic or alkaline soils via chemical methods like liming or using acidic materials. Instead, we may try to select the crops and varieties that can better withstand soil acidity or alkalinity. This stance will be more welcomed when the conservation of environments is high priority issue.

• Journal for History of Mathematics
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• v.32 no.5
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• pp.217-231
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• 2019

Mathematics and philosophy are considered as ways to get knowledges and cognitions of truths. They are human thoughts and epistemes. Thinking is in fact carried out in a systematic way, which consists of sort of syntax and semantics of thinking, called logic. We observe the logic from mathematical and philosophical perspectives with layman's language. We conclude that mathematics, philosophy and logic are the abilities necessary for the human beings of the 21st century, the age of artificial intelligence.