• The Journal of Information Systems
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• v.26 no.1
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• pp.93-123
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• 2017

Purpose The purpose of this study is to deduct the factors for explaining the economic behavior of an Internet user who provides personal information notwithstanding the concern about an invasion of privacy based on the Information Privacy Calculus Theory and Communication Privacy Management Theory. Design/methodology/approach This study made a design of the research model by integrating the factors deducted from the computation theory of information privacy with the factors deducted from the management theory of communication privacy on the basis of the Dual-Process Theory. In addition, this study, did empirical analysis of the path difference between groups by dividing Internet users into a group having experience in personal information spill and another group having no experience. Findings According to the empirical analysis result, this study confirmed that the Privacy Concern about forms through the Perceived Privacy Risk derived from the Disposition to value Privacy. In addition, this study confirmed that the behavior of an Internet user involved in personal information offering occurs due to the Perceived Benefits contradicting the Privacy Concern.

• Journal of Advanced Marine Engineering and Technology
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• v.20 no.4
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• pp.20-26
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• 1996

Recently, for the speed control of a diesel engine, some methods using the modern control theory such as LQ control technique, or $\textit{H}_{\infty}$control theory etc., have been reported. However, most of speed controlers of a diesel engine ever developed are still using the PID control algorithm. And, as another approach to the speed control of a diesel engine, the authors proposed already a new method to adjust the parameters of the PID controller by a model matching method. In the previous paper, the authors confirmed that the proposed new method is superior to Ziegler & Nichols's method through the analysis of results of the digital simulations under the assumption that the parameters of a diesel engine are known exactly. But, actually, it is very difficult to find out the value of parameters of a diesel engine accurately. And the parameters of a diesel engine are changigng according to the operating condition of a diesel engine. So, in this paper, a method to estimate the parameters of the PID controller for the speed control of a diesel engine by means of the model matching method are proposed. Also, the digital simulations are carried out in cases either with or without measurement noise. And this paper confirms that the proposed method here is superior to Ziegler & Nichols's method through the analysis of the characteristics of indicial responses.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.3 s.246
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• pp.295-301
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• 2006

The wheel slip control systems are able to control the braking force more accurately and can be adapted to different vehicles more easily than conventional ABS systems. In order to achieve the superior braking performance through the wheel-slip control, real-time information such as the tire braking force at each wheel is required. In addition, the optimal target slip values need to be determined depending on the braking objectives such as minimum braking distance, stability enhancement, etc. In this paper, a robust wheel slip controller is developed based on the adaptive sliding mode control method and an optimal target slip assignment algorithm. An adaptive law is formulated to estimate the longitudinal braking force in real-time. The wheel slip controller is designed using the Lyapunov stability theory and considering the error bounds in estimating the braking force and the brake disk-pad friction coefficient. The target slip assignment algorithm is developed for the maximum braking force and searches the optimal target slip value based on the estimated braking force. The performance of the proposed wheel-slip control system is verified In simulations and demonstrates the effectiveness of the wheel slip control in various road conditions.

• Journal of applied mathematics & informatics
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• v.14 no.1_2
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• pp.97-113
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• 2004

In this paper we shall study moving boundary problems, and we introduce an approach for solving a wide range of them by using calculus of variations and optimization. First, we transform the problem equivalently into an optimal control problem by defining an objective function and artificial control functions. By using measure theory, the new problem is modified into one consisting of the minimization of a linear functional over a set of Radon measures; then we obtain an optimal measure which is then approximated by a finite combination of atomic measures and the problem converted to an infinite-dimensional linear programming. We approximate the infinite linear programming to a finite-dimensional linear programming. Then by using the solution of the latter problem we obtain an approximate solution for moving boundary function on specific time. Furthermore, we show the path of moving boundary from initial state to final state.

• Journal of Korean Academy of Nursing
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• v.35 no.7
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• pp.1201-1209
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• 2005

Purpose: The purpose of this study was to identify the effects of a value clarification program on value clarification in juvenile delinquents. This study employed a two-group pre-post test study design. Data was collected from 16 subjects from Sept. 29 to Dec. 26, 2003 at N middle school in Seoul, Korea. 9 subjects constituted the control, while the experimental group was composed of 7 subjects. Method: The structured group therapy used in this study was developed on the basis of Raths et al. (1978) theory. The subjects participated in 10 sessions of therapy that lasted 60 minutes. The instruments used were value clarification Test (Lee, 1988), and SPSS Window. Result: The experimental group showed a significant increase in value clarification after their participation in the program. Conclusion: Based upon the findings it was concluded that a value clarification program was effective in improving value clarification in juvenile delinquents in the study.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.7C
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• pp.664-669
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• 2002

In this paper, we propose the fuzzy control algorithm for effective buffer control to connected traffic in ATM networks. The proposed Fuzzy control algorithm has two priorities and uses Fuzzy sets to search for dynamic thresholds. In this words, the difuzzification value controls the threshold in the buffer to according to traffic priority (low or high) using fuzzy set theory for traffic connected after reasoning. Performance analysis result: it was confirmed that with the proposed scheme, performance improves at cell loss rate, when compared with the existing PBS scheme.

• The Transactions of the Korean Institute of Power Electronics
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• v.8 no.5
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• pp.442-449
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• 2003

This paper discusses how to generate the reference compensation voltages in Dynamic Voltage Restorers (DVR) by use of PQR instantaneous power theory. Sensed three-phase terminal voltages are transformed to PQR coordinates without time delay. Since the reference voltage in PQR coordinates is a single dc value, the voltage controller for DVRs is simple and easy to design. Proposed control method can be implemented by feedforward controllers or by feedback controllers. This paper verified the theory by a feedforward controller of a DVR with simulation and experiment.

• Journal of the Korean Society for Library and Information Science
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• v.56 no.1
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• pp.425-447
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• 2022

The purpose of this study is to introduce the Theory of Information Worlds which analyzes information behaviors in the social perspective. This study analyzed dissertations using the theory to provide the understanding of the theory and suggest theoretical implications. The theory was developed by Burnett and Jeager in 2008, and since then it was applied in 14 dissertations. Key concepts of the theory include social norms, social types, information value, information behavior, and boundaries. These concepts are intervened in the process of creation and control of behavior through interaction each other. Qualitative research was adopted in more research rather than quantitative research; especially interview and content analysis were applied. It is expected that the spectrum of information behavior research in Korea is broaden and deeper through this study.

• Earthquakes and Structures
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• v.5 no.4
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• pp.395-416
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• 2013

The magneto-rheological (MR) damper contributes to the new technology of structural vibration control. Its developments and applications have been paid significant attentions in earthquake engineering in recent years. Due to the shortages, however, inherent in deterministic control schemes where only several observed seismic accelerations are used as the trivial input and in classical stochastic optimal control theory with assumption of white noise process, the derived control policy cannot effectively accommodate the performance of randomly base-excited engineering structures. In this paper, the experimental and analytical studies on stochastic seismic response control of structures with specifically designed MR dampers are carried out. The random ground motion, as the base excitation posing upon the shaking table and the design load used for structural control system, is represented by the physically based stochastic ground motion model. Stochastic response analysis and reliability assessment of the tested structure are performed using the probability density evolution method and the theory of extreme value distribution. It is shown that the seismic response of the controlled structure with MR dampers gain a significant reduction compared with that of the uncontrolled structure, and the structural reliability is obviously strengthened as well.

• KIEAE Journal
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• v.14 no.4
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• pp.5-10
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• 2014

Since construction work is an indispensable part of daily lives, complaints of noise are unavoidable. Noise control in construction sites is normally known as a regulation by a government and self-motivated noise controls rarely occur. In this paper, a marketing strategy is proposed to provide a potential value of noise control for real estate developer. First, people's perception to construction noise was examined in means of collecting and analyzing media reports between 2005 to 2011. Then decibel test was done in order to test noise generated by different devices in a construction site in various distances. According to the theory of core competency, a conceptual model was raised to illustrate profit and loss situation of the real estate developers in the case they invest more in noise control. The construction noise is discussed that it will ruin people's perception to the company's brand image and reputation. Also, the investment in the creation of silent site is discussed that it will not only bring benefit to the brand image work but also have value of profit in the market.