• KIEE International Transactions on Power Engineering
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• v.4A no.1
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• pp.33-41
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• 2004

Knowledge of partial discharge (PD) is important to accurately diagnose and predict the condition of insulation. The PD phenomenon is highly complex and seems to be random in its occurrence. This paper indicates the possible use of chaos theory for the recognition and distinction concerning PD signals. Chaos refers to a state where the predictive abilities of a systems future are lost and the system is rendered aperiodic. The analysis of PD using deterministic chaos comprises of the study of the basic system dynamics of the PD phenomenon. This involves the construction of the PD attractor in state space. The simulation results show that the variance of an orthogonal axis in an attractor of chaos theory increases according to the magnitude and the number of PDs. However, it is difficult to clearly identify the characteristics of the PDs. Thus, we calculated the magnitude on an orthogonal axis in an attractor using singular value decomposition (SVD) and principal component analysis (PCA) to extract the numerical characteristics. In this paper, we proposed the condition monitoring method for gas insulated switchgear (GIS) using SVD for efficient calculation of the variance. Thousands of simulations have proven the accuracy and effectiveness of the proposed algorithm.

• Journal of Digital Convergence
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• v.17 no.1
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• pp.131-140
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• 2019

The development of the knowledge information system is increasing the symptoms that people refuse to remember. There is also a growing debate about whether to remember knowledge. This study investigated the preference of memorizing knowledge and finding knowledge. We predicted the use, effect, and expectation of ease of use of knowledge utilization that will appear in the future among preference groups. We analyzed whether there is a difference between the predicted expectations of knowledge utilization in the future. The first study was conducted in October 2014. This is the second study. We studied what changes were made in comparison with the first study. As a result, it was found that 1) there is no difference in broadening the diversity of knowledge utilization at future time, 2) expectation of the effect of knowledge utilization, and 3) ease of continuous knowledge creation. The results of this study suggest that it is important to provide a basis for discussing whether it is good to remember knowledge.

• Information Systems Review
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• v.2 no.1
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• pp.119-132
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• 2000

• Knowledge Management Research
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• v.22 no.4
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• pp.119-133
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• 2021

As a large amount of data is produced in each industry, a number of time series pattern prediction studies are being conducted to make quick business decisions. However, there is a limit to predicting specific patterns in nonlinear time series data due to the uncertainty inherent in the data, and there are difficulties in making strategic decisions in corporate management. In addition, in recent decades, various studies have been conducted on data such as demand/supply and financial markets that are suitable for industrial purposes to predict time series data of irregular random walk models, but predict specific rules and achieve sustainable corporate objectives There are difficulties. In this study, the prediction results were compared and analyzed using the Chaos analysis method for roulette data and financial market data, and meaningful results were derived. And, this study confirmed that chaos analysis is useful for finding a new method in analyzing time series data. By comparing and analyzing the characteristics of roulette games with the time series of Korean stock index future, it was derived that predictive power can be improved if the trend is confirmed, and it is meaningful in determining whether nonlinear time series data with high uncertainty have a specific pattern.

• Korean Institute of Interior Design Journal
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• v.14 no.2 s.49
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• pp.197-205
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• 2005

In estimating designed architectural buildings, many factors in various design domains such as function, structure, form, environment may be considered and then a building design might be selected or modified as final design from many possible design results. This paper proposed a method to obtain complexity values from two dimensional drawings which are floor plans or elevations. The Complexity values could be turned into esthetic values. The method has been developed based on information theory, shape pattern representation and cognitive theory. Results of measuring complexity value can make the computer evaluate and select final results produced from automatic design processes by the computer That is to say, aesthetic values based on order and chaos can be measured using complexity values and then some results having superior values can be selected as final result. Also some cognitive processes as perception of two dimensional drawings are discussed using shape representations. Aesthetic values could be varied in terms of shape properties such as size, individualities and knowledge as well as order and chaos.

• Journal of Family Resource Management and Policy Review
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• v.16 no.2
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• pp.145-163
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• 2012

The purpose of this study is to understand the process of "standing alone" in divorced single fathers on the basis of qualitative data collected through in-depth interviews with 10 divorced single fathers. Data were analyzed on the basis of grounded theory analysis in open coding, and 154 concepts, 39 sub-categories, and 14 categories were derived. According to the results of this study, the process phenomenon of divorced single fathers' standing alone was "the restraint and chaos of pain". This study could identify the consecutive process of four identified stages: marriage life's rupture, pain and chaos, deliberation and decision, and role adaption. In selective coding, the core category was "to pass through the restraint of pain and embrace children and stand alone". There were three types of standing alone: maintaining barely, enduring hopefully, and living initiatively. This study showed the necessity of social support and the basic data by type analysis through the process of standing alone. This study provided substantive knowledge generated through the voices of the persons concerned.

• Journal of Sasang Constitutional Medicine
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• v.12 no.2
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• pp.1-7
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• 2000

Greeting the 100 year celebration of the death of Master Dong-mu, through investigating his thoght on Scholarship and Philosophy, and his new view of human being based on Sasang, I tried to reevaluate him as a Confucianist of practical mind. The conclusions were as followings ; 1. Dong-mu's recognition system of things is that based on the mind of summarizing things in view of Affair-Mind-Body-Object originated from Confucianism, and It developed 'the Marvel of Easiness & simpleness based on Yin-yang' into 'the Marvel of Easiness & simpleness based on Sasang' 2 Through understanding old Confucianism newly, Dong-mu summarized human being as having a natural character in view of Nature and Order and an autonomical character in view of Knowledge and Deed, and emphasized an autonomical character in view of Knowledge and Deed 3. In view of Knowledge and Deed, Dong-mu presented How to Say and Behave, and took it as a model of behavior in the new Confucianism. Also he presented the view of Knowledge and Deed based on Constitutions, and took it as a new mind of treatment. 4. Dong-mu can be estimated highly, in that he completed a new confucian view-point of Human being in the period of philosophic chaos, and executed the mind of General health maintenance and the mind of control others through a confucian self-control.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1997.10a
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• pp.181-184
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• 1997

Practical applications of learning systems usually involve complex domains exhibiting nonlinear behavior and dilution by noise. Consequently, an intelligent system must be able to adapt to nonlinear processes as well as probabilistic phenomena. An important class of application for a knowledge based systems in prediction: forecasting the future trajectory of a process as well as the consequences of any decision made by e system. This paper examines the robustness of data mining tools under varying levels of noise while predicting nonlinear processes in the form of chaotic behavior. The evaluated models include the perceptron neural network using backpropagation (BPN), the recurrent neural network (RNN) and case based reasoning (CBR). The concepts are crystallized through a case study in predicting a Henon process in the presence of various patterns of noise.

• Journal of the Korean Society for Library and Information Science
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• v.44 no.3
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• pp.5-24
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• 2010

The public library is the local centre and gateway of knowledge and information. Therefore, the library should be funded and operated by local government and the governing body will be responsible for matters of policy of the library. However, recently public libraries in Korea have faced enormous policy challenges such as the damage of its identity, outsourcing or contracting-out of management, and the general chaos of its administrative system. This paper aims to analyze the current level of infrastructure and policies of public libraries and to review the wrong path and the right path of library policies focused on establishing a library foundation and outsourcing library management in Seoul and Incheon.

• Wind and Structures
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• v.36 no.3
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• pp.215-220
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• 2023

We study the progressive full-scale wind tunnel tests on a high solidity vertical axis wind turbine (VAWT) for various tip speeds and pitch angles to understand the VAWT shaft system's dynamics using 0-1 Test for chaos. We identify that while varying rotor speed (tip speed) of the turbine, the system's dynamics change from periodic to chaotic through quasiperiodic and strange non-chaotic (SNA) states. The present study is the first experimental evidence for the existence of these states in the VAWT shaft system to the best of our knowledge. Using the asymptotic growth value Kc in 0-1 test, when the turbine operates at the low tip speeds and high pitch angles for low incoming wind speeds, the system behaves periodic (Kc ≈ 0). However, when the incoming wind speed increases further the system's dynamics shift from periodic to chaotic vibrations through quasi-periodic and SNA. This phenomenon is due to the dynamic stalling of blades which induces chaotic vibration in the VAWT shaft system. Further, the singular continuous spectrum method validates the presence of SNA and differentiates the SNA from chaotic vibrations.