• 대한기계학회논문집
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• 제18권9호
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• pp.2339-2348
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• 1994

The objective of this paper is to develop a solution method for the differential-algebraic equation(DAE) derived from constrained muti-body dynamic systems. Mechanical systems are often modeled as bodies and joints. Differential equations of motion are formulated for bodies. Since the bodies are connected by joint, the differential variables must satisfy the kinematic constraint equations that come from the joints. Difficulties are arised due to drift of the differential variables off the constraint equations. An optimization method is adopted to correct the drift of the differential variables. To demonstrate the efficiency of the proposed method a slider-crank mechanism is analyzed dynamically. Identical results are obtained as these from the commercial program DADS. Dynamic analysis of a High Mobility Multi-purpose Wheeled. Vehicle(HMMWV) is carried out to show the practicalism of the proposed method.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.294-298
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• 1996

This paper presents an attempt to find the physical structure of dynamic systems which achieves the behavior of a given system function. The scheme pursued by te paper would be regarded as synthesizing dynamic systems, and a method to synthesize them analytically is proposed by means of bond graph prototypes. The method proposed adopts several concepts used to synthesize networks in the electrical field, but yet demonstrates its own strengths such as the freedom from the causality assignment and determination of junction types. Also, it is shown that this method has further advantages in reticulating a given specification into feedforward and feedback expansions relative to electrical network synthesis and the method introduced by Redfield. The proposed method is examined through an example to trace the outline of the analytical synthesis of dynamic systems using bond graph prototypes.

• Geomechanics and Engineering
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• 제9권2호
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• pp.145-167
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• 2015

Digital simulation has recently become the preferred method for designing complex and dynamic systems. Simulation packages provide interactive, block-diagram environment for modeling and simulating dynamic models. The block diagrams in simulation models are flowcharts which describe the components of dynamic systems and their interaction. This paper is the first part of the study for determining the seismic behavior of soil systems. The aim of this part is to present the constructed block diagrams for discrete-time analysis of seismic site amplification in layered media for vertically propagating shear waves. Detailed block diagrams are constructed for single and multiple soil layers by considering wave propagation with and without damping, respectively. The block diagrams for recursive filter to model attenuation in discrete-time form are also constructed. Finite difference method is used for strain calculation. The block diagrams are developed by utilizing Simulink which is a software add-on to Matlab.

• 제어로봇시스템학회논문지
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• 제17권4호
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• pp.304-312
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• 2011

In an oligopolistic market, only a few firms account for most or all of total production, e.g., automobile, steel, and computer industries. For a dynamic oligopolistic market with two firms competing in quantities, we show that supervisory control theory of discrete event systems provides a novel approach to solve the dynamic oligopoly problem with the aim of maximizing the profits of both firms. Specifically, we show that the controllability, observability, and nonblocking property (which are the core concepts in supervisory control theory) are the necessary and sufficient conditions for two oligopolistic firms in disequilibrium to eventually reach equilibrium states of maximizing the profits of both firms.

• 반도체디스플레이기술학회지
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• 제14권3호
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• pp.37-43
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• 2015

In this paper, a new background subtraction algorithm for video based fence monitoring surveillance systems is proposed. We adopt the sampling based background subtraction technique and focus on the two main issues: handling highly dynamic environment and handling the flickering nature of pulse based IR (infrared) lamp. Natural scenes from fence monitoring system are usually composed of several dynamic entities such as swaying trees, moving water, waves and rain. To deal with such dynamic backgrounds, we utilize the confidence factor for each background value of the input image. For the flickering IR lamp, the original sampling based technique is extended to handle double background models. Experimental results revealed that our method works well in real fence monitoring surveillance systems.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 II
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• pp.838-843
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• 2001

Internal damping plays an important role in some rotor dynamic systems with the use of various materials for shafts, for example, composite material. However, although the effects of internal damping have been investigated for a couple of decades, there are several different internal damping models in use, none of which are accepted as the most reliable model. The purpose of this paper is to compare the results of dynamic analysis of rotor systems with several different internal damping models. The exact dynamic element method is used to formulate and analyze the problem. The simulation results provided in this paper may be useful for the dynamic analysis of high rotor systems subject to significant internal damping.

• Nonlinear Functional Analysis and Applications
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• 제29권3호
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• pp.899-912
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• 2024

The objective of this paper is to ascertain the existence and uniqueness of common fixed point for four self mappings in intuitionistic Menger metric spaces under some conditions extending to (CLR) property and C-class functions. Some illustrative examples are furnished, which demonstrate the validity of the hypotheses. As an application to our main result, we derive a common fixed point theorem for four self-mappings in metric space. Our results generalize several works, including [4], [20].

• 대한전기학회논문지:시스템및제어부문D
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• 제50권7호
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• pp.325-331
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• 2001

A dynamic anti-windup method for state delayed control systems with input saturation is considered. Under the assumption that a linear controller has been designed for a state delayed control system based on the existing design technique which shows desirable nominal performance, an additional compensator is incorporated to provide a graceful performance degradation despite of input saturation. By regarding the difference of the controller states in the absence and presence of input saturation as an objective function, the dynamic compensator which minimizes it is determined explicitly. The proposed dynamic compensator is the closed form of plant and controller parameters. The proposed method not only provides graceful performance degradation, but it also guarantees the total stability of resulting systems. An illustrative example is provided to show the effectiveness of the proposed method.

• 한국정밀공학회지
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• 제15권12호
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• pp.188-193
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• 1998

This paper describes static and dynamic weak point analysis of spindle systems to eliminate high concentrated bending point on spindle and improve total stiffness of spindle systems. The weak point analysis is based on the evaluation of bending curves of spindles. For static weak point analysis the bending curve is derived from static deflection curve and for dynamic weak point analysis it is derived from the mode shape curves in consideration of the transfer function at exciting point. The validity of the weak point search methodology is verified by comparison of the static deflection, the natural frequency and the dynamic compliance between the original and the improved spindle.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.179-184
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• 1991

This paper will describe the application for variable structure control theory to the first order dynamic system and verify it's robustness. The study on the first order dynamic system control which has been essential part for the control of servo motor (AC, DC) systems has been excluded in the study of variable structure control system(VSCS) because this first order system was not applicable to the previous variable structure control theory. So, for the robustness control of first order dynamic system with variable structure control theory, we propose modified switching function synthesis which guarantees the advantages of conventional VSCS and removes reaching phase which regards as shortcomings in VSCS. And we demonstrate the practical potential of implementation about this theory by simulation results of AC motor variable speed control.