• 대한기계학회논문집
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• 제19권7호
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• pp.1657-1664
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• 1995

For dynamic analysis of flexible structures, classical linear modeling has been widely used due to its several good aspects. However, it was found that the modeling often lost its accuracy. So, it is important to know the valid range of the modeling before it is used. more complicated modelings are needed to obtain reliable results only outside the valid range of the classical linear modeling. In this study, some rigid body motions of flexible structures which lead to the failure of the classical linear modeling are investigated. Hybrid deformation variable modeling, which is proved to be accurate in previous studies, is used to figure out the valid range of the classical linear modeling through numerical examples.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.1013-1016
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• 1995

This paper deals with dynamics and control of a PRP6-DOF parallel manipulator. Dynamic modeling includes the effect of inertia of all links in the mechanism to increase modeling accuracy. Kinematic analysis about forward and inverse kinematics is also explained. Using Lagrange-D' Alambert method we get equations of motions in a link space which fully represent 6DOF motions of the manipulator.

• Korean Journal of Geomatics
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• 제3권1호
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• pp.23-32
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• 2003

Rigorous sensor and dynamic modeling techniques are required if spatial information is to be accurately extracted from video imagery. First, a mathematical model for an uncalibrated video camera and a description of a bundle adjustment with added parameters, for purposes of general block triangulation, is presented. This is followed by the application of invariance-based techniques, with constraints, to derive initial approximations for the camera parameters. Finally, dynamic modeling using the Kalman Filter is discussed. The results of various experiments with real video imagery, which apply the developed techniques, are given.

• 한국철도학회논문집
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• 제10권4호
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• pp.431-437
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• 2007

This paper describes the dynamic modeling of a railway vehicle when it is under braking force. It is important for the enhancement of braking performance to establish a proper dynamic model of a railway vehicle because the braking performance is affected by some dynamic forces generated by a railway vehicle when it undergoes braking. In this paper, a dynamic model for one vehicle is suggested to compute the dynamic behavior of a railway vehicle in the HILS(Hardware In-the-loop Simulation) system for the railway vehicle braking devices. To simplify the dynamic model, friction between a wheel and a rail is assumed that there exist only the static and the dynamic friction forces. Static friction coefficient is also assumed to be a function of the running speed. Some simulations are carried out with various braking forces, and the braking characteristics according to the change of the braking force are discussed. This study can provide some fundamental results to construct the HILS system for braking devices of a railway vehicle.

• International Journal of Control, Automation, and Systems
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• 제4권2호
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• pp.197-203
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• 2006

This paper addresses dynamic modeling and task-space trajectory following issues for nonholonomic mobile manipulators moving on a slope. An integrated dynamic modeling method is proposed considering nonholonomic constraints and interactive motions. An adaptive neural-fuzzy controller is presented for end-effector trajectory following, which does not rely on precise apriori knowledge of dynamic parameters and can suppress bounded external disturbances. Effectiveness of the proposed algorithm is verified through simulations.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.424-429
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• 2008

Aircraft flutter analysis model consists of dynamic FE model and aerodynamic model. Dynamic FE model is composed of stiffness and mass model, and is used for the prediction of normal mode characteristics of the structure. Since aircraft flutter analysis is normally performed in the modal domain, dynamic FE model shall be constructed to describe the modal characteristics of the structure with sufficient accuracy. In this study, dynamic FE modeling method was described using full airframe FE model and structural and system weight data for aircraft flutter analysis. In addition, full airframe dynamic FE model for composite small aircraft was constituted for normal mode and flutter analysis, and the mass modeling results were compared with the target weight data to validate the mass modeling method proposed. Finally, full airframe flutter analysis of composite small aircraft was performed with the dynamic FE model and the aerodynamic model composed.

• 한국경영과학회지
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• 제22권3호
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• pp.175-190
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• 1997

Organizational change projects such as Business Process Redisign (BPR) have been perceived to incur high risk due to their high management complexity, enterprise-wide impace, and steep project cost. This research intends to reduce such risk by developing a systematic process redesign methods, called Dynamic Process Modeling (DPM) method. DPM integrates the customer-oriented business process modeling technique with computerized visual simulation technique to promote better understanding of the target process and enable performance simulation of the proposed redesign alternatives prior to actual BPR implementations. For the cusstomer-oriented process modeling, we propose Dynamic-Event Process Chain (Dynamic-EPC) extending from the conceptual customer process model, Event-Process Chain (EPC). We compare DPM with four other implementation-level process modeling methods over eight criteria and demonstrate its effectiveness by applying it to the real-world hospital BPR case.

• 제어로봇시스템학회논문지
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• 제14권9호
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• pp.916-924
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• 2008

In this paper dynamic modeling parameters were estimated using a frequency domain estimation method. A systematic flight test method was employed using preprogrammed multistep excitation of the swashplate control input. In addition when one axis is excited, the autopilot is engaged in the other axis, thereby obtaining high-quality flight data. A dynamic model was derived for a small scale unmanned helicopter (CNUHELI-020, developed by Chungnam National University) equipped with a Bell-Hiller stabilizer bar. Six degree of freedom equations of motion were derived using the total forces and moments acting on the small scale helicopter. The dynamics of the main rotor is simplified by the first order tip-path plane, and the aerodynamic effects of fuselage, tail rotor, engine, and horizontal/vertical stabilizer were considered. Trim analysis and linearized model were used as a basic model for the parameter estimation. Doublet and multistep inputs are used to excite dynamic motions of the helicopter. The system and input matrices were estimated in the frequency domain using the equation error method in order to match the data of flight test with those of the dynamic modeling. The dynamic modeling and the flight test show similar time responses, which validates the consequence of analytic modeling and the procedures of parameter estimation.

• 대한조선학회논문집
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• 제47권6호
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• pp.808-812
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• 2010

This paper studies the finite element modeling and analytical parameters for the numerical evaluation of dynamic stiffness of large foundation for shipboard equipments such as marine diesel engine. For the purpose, numerical method and procedure to evaluate the dynamic stiffness are established based on the impact test method, which are applied for the dynamic stiffness evaluation of a real diesel generator foundation of ship. Numerical investigations compared with the measured data are carried out to evaluate the effects of modeling ranges of ship substructure, finite element sizes, lower support structures and damping coefficients. From the results, modeling and analytical parameters for proper evaluation of dynamic stiffness of large foundation of shipboard equipment are suggested.

• 대한기계학회논문집A
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• 제25권3호
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• pp.362-368
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• 2001

To design a limiting MCCB (Molded Case Circuit Breaker) mechanism, a dynamic modeling of the mechanism in which the electro-magnetic force effects are incorporated needs to be developed. Conventionally, electro-magnetic effects were considered separately for the design of the mechanism. In this paper, an electro-magnetic force that is induced by limited current is identified and included in the dynamic modeling of the mechanism. Thus, the electro-magnetic which is defined as a external force and the mechanical effects are simultaneously considered for the design of the mechanism which is composed of contactor, spring , link, latch and so on.