• International Journal of Control, Automation, and Systems
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• v.3 no.spc2
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• pp.302-307
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• 2005

A novel neuro controller based simple neuro-structure with modified error function is introduced in this paper. This controller consists of two independent controllers, known as the voltage regulator and the angular controller. The voltage regulator is used to modify terminal voltage for the purpose of tracking a reference voltage. The angular controller is utilized to guarantee the stability of the system. In this structure each neuron uses a linear hard limit activation function that depends on the controlled variable and its derivatives. There is no need for parameter identification or any off-line training data. Two proposed controllers are merged by a smooth switch to build a complete controller. The effectiveness of the proposed novel control action is demonstrated through some computer simulations on a Single-Machine Infinite-Bus (SMIB) power system.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.5
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• pp.315-319
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• 2016

This paper proposes a simple adaptive sliding mode control algorithm for controlling a permanent magnet synchronous generator (PMSG) of a MW-class direct-driven wind turbine system. The proposed adaptive sliding mode controller does not require accurate knowledge of the PMSG parameter or turbine torque values. The proposed controller can accurately track the reference angular speed computed by the maximum power point tracking(MPPT) algorithm. Finally, this paper gives Matlab/Simulink simulation results to verify the practicality and effectiveness of the proposed adaptive sliding mode controller.

• International Journal of Internet, Broadcasting and Communication
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• v.7 no.2
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• pp.105-108
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• 2015

There are a lot of traffic jams in the metropolitan area and the commuting time has been longer nowadays. So the urban people has been interested in the GTX(Great Train Express) project in Korea. The GTX is the train which runs at 200km/h speed in underground tunnels. If the train also operates at high speed in tunnel section, the pressure wave will happen and the uplift force of pantograph may vary abruptly. If the rigid trolley bar system is used in tunnel section, it is difficult to improve the commercial speed of train. In order to improve the train speed in tunnel section, this paper presents the new pantograph concepts which can change the suspension stiffness and deals with the dynamic behavior characteristics of pantograph according to the parameter variation.

• Journal of the Korea Society of Computer and Information
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• v.23 no.7
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• pp.113-120
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• 2018

The purpose of this study is to derive implications for effective management of the public social worker by investigating the relationship between social support, job attitude and self-esteem of the public social worker. In order to accomplish this research purpose, social support of the public social worker as independent variables, job attitude as a dependent variable, and self-esteem as a parameter were analyzed and the relationship between these variables was analyzed. As a result, emotional, evaluative, material, and informational support, which constitute the social support of the public social worker, have a significant effect on job attitude, and self-esteem has a mediating effect on the relationship between these variables. Based on the results of this analysis, the importance of social support of the public social worker was suggested.

• Journal of Korean Society for Quality Management
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• v.36 no.4
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• pp.19-28
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• 2008

The purpose of this study is to search for the quality characteristics for evaluation of the information system. The quality characteristics are an important factor for selection, implementation and maintenance of the information system of the company. Of course in the end, the quality of the information system in a company is directly related with the business performance of the company. This paper is a study of a model with four independent variables, a parameter variable, and a total of 15 hypotheses, investigated by a questionnaire method. It conducted the model analysis of structural equation to use statistical package for questionnaire analysis.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.12
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• pp.1441-1446
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• 2014

Love which is one of the emotional of mankind, has been studied in sociology and psychology as a matter of grate concern. In this paper we propose a modified romantic behaviors by using basic the love equation of Romeo and Juliet. We represent the behaviors using time series and phase portrait when we vary the parameter in the modified love equation. Also we analyze the behavior's relation by using time series and phase portraits when external force applied as the third person between Romeo and Juliet.

• 전기의세계
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• v.30 no.12
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• pp.822-831
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• 1981

Many different schemes of the adaptive observer and controller have been developed for both continuous and discrete systems. In this paper we have presented a new scheme of the reduced order adaptive observer for the single input discrete linear time invariant plant. The output equation of the plant, is transformed into the bilinear form in terms of system parameters and the states of the state variable filters. Using the plant output equation the discrete implicit adaptive observer based on the similar philosophy to Nuyan and Carroll is derived and the parameter adaptation algorithm is derived based on the exponentially weighted least square method. The adaptive model following control system is also constructed according to the proposed observer scheme. The proposed observer and controller are rather than simple structure and have a fast adaptive algorithm, so it may be expected that the scheme is suitable to the practical application of control system design. The effectiveness of the algorithm and structure is illustrated by the computer simulation of a third order system. The simulation results show that the convergence speed is proportinal to the increasing of weighting factor alpha, and that the full order and reduced order observer have similar convergence characteristics.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.38 no.12
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• pp.983-994
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• 1989

This paper presents a new variable structure model following control algorithm for control of manipulators. The reference model is a simple double integrators and the acceleration input for the robot manipulator consists of a proportional and derivative controller for the purpose of trajectory tracking. The control algorithm is derived by using Lyapunov stability theory instead of S.S < O, as is usual in the current VSS controller design. This proposed control algorithm does not require good knowledge of the parameter in the inertia matrix and is easily extendable to robot manipulators with a higher number of links. Also, the new algorithm is computationally fast because of not requiring the matrix inversion. The computer simulation was carried out to evaluate the performance of the proposed VSMFC.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.145-147
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• 2002

In this paper, the improved fault locating method using distributed parameter which calculating the reduced voltage and current according to the ground capacitance in long transmission line was proposed. For the purpose of the fault locating algorithm non influenced source impedance, the loop method was used in the system modeling analysis. To enhance the fault locating, zero sequence of the fault current which is variable according to ground capacitance was not used but positive and negative sequence. System model was simulated using EMTP software. To verify the accuracy of proposed method, in different cases 64 sampled data per cycle was used and 160km and 300km long transmission line has fault resistance $0{\Omega}\;and\;100{\Omega}$ respectively was compared.

• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.853-855
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• 1999

The induction machine has been used frequently for the system that needs static speed because of its simplicity, durability, credibility and efficiency. But it is nonlinear system for its multi-variable interference. Its controller is more complicated than DC machine's one. So vector control method is needed for its high Performance control. This paper shows that vector control algorithm could be more fast and stable by using Genetic algorithm (GA) based upon Darwin's evolution theory and Mendel's genetics. Methods proposed in here are used to design induction machine's vector controller and to use GA for optimizing the controller's parameter. SIMULINK of MATLAB is used for analysis and conviction of control property