• Journal of the Society of Naval Architects of Korea
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• v.61 no.4
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• pp.247-257
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• 2024

The present study suggests a data-driven multivariate identification method based on principal component analysis and shows an application to ship dynamics modeling in maneuver. A reduced order model of ship dynamics is built by linear combination of three principal components acquired from large angle zigzag maneuver test. For a given kinematic state with three variables, a proper span is found by least square method, therefore accompanying hydrodynamic force and moment is determined. Suggested dynamics model correctly estimates hydrodynamic force and moment, thus it showed good agreement in maneuver simulation with that of conventional ship dynamics model obtained by system identification of captive model tests.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.444-448
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• 2003

In this paper, the Lagrange dynamics is studied. A state space representation of Lagrange dynamics and control algorithm based on the state feedback pole placement are presented. The state space model presented is descriptor type linear parameter dependent system. It is shown that the control algorithms based on the linear system theory can be applicable to the state space representation of Lagrange dynamics. To show that the linear system theory can be applicable to the state space representation of Lagrange dynamics, the LMI based regional pole-placement design algorithm is developed and present two examples.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.2
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• pp.409-425
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• 2015

In this paper, we employ a dynamics modeling method for investigating a multi-body dynamics system of semi-submersible autonomous underwater vehicles consisting of a towing vehicle operated near the water surface, a tow cable, and a towfish. The towfish, which is towed by a marine cable for the purposes of exploration or mine hunting, is modeled with a Six-Degree-of-Freedom (6-DOF) equation of motion that reflects its hydrodynamics characteristics. The towing cable, which can experience large displacements and deformations, is modeled using an absolute nodal coordinate formulation. To reflect the hydrodynamic characteristics of the cable during motion, the hydrodynamic force due to added mass and the drag force are imposed. To verify the completeness of the modeling, a few simple numerical simulations were conducted, and the results confirm the physical plausibility of the model.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.10a
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• pp.614-622
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• 2011

In this study, the computational structural dynamic modeling of floating offshore wind turbine system is presented using efficient equivalent modeling technique. Structural dynamic behaviors of the offshore floating platform with 5MW wind turbine system have been analyzed using computational multi-body dynamics based on the finite element method. The considered platform configuration of the present offshore wind turbine model is the typical spar-buoy type. Equivalent stiffness and damping properties of the floating platform were extracted from the results of the baseline model. Dynamic responses for the floating wind turbine models are presented and compared to investigate its structural dynamic characteristics. It is important shown that the results of the present equivalent modeling technique show good and reasonable agreements with those by the fully coupled analysis considering complex floating body dynamics.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.906-909
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• 2005

This study provides the method to build the rotor system model using dynamic analysis software. also, it introduces the traditional methods of the rotor system modeling and informs the each merits and demerits. We will make up the flexible system of rotor system model with ADAMS, multi-body dynamics S/W, in order to develop dynamics model and get the response of plant model near to real model through connection the SIMULINK of MATLAB. We will develop the computing dynamics-controling model possible controlled simulation similar to a real model with controlling the plant model.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.2
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• pp.59-68
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• 2002

This Paper presents the dynmics modeling and the operation simulation of the 500 MW drum-type boiler and its control system hosted in the Boryung Power Plant unit #1 and #2. The fidelity of the modeling and the operation simulation is well verified by their agreement with the actual data obtained form the plant operation. As a plant signal generator for the various operation patterns and fault situations, the simulation environment will be utilized to develope the fault detecting signal processing algorithms.

• Korean System Dynamics Review
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• v.10 no.3
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• pp.25-45
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• 2009

The concept of social capital has recently been highlighted in most fields of social science because social capital is believed to be an alternative of market and government failures. However, social capital is of high ambiguity that hinders in conceptualizing and modeling that can differs from the premises, such as whether social capital lies in individual actors or collective substances, or whether social networks are functioning by rationality or emotion. This study therefore tries to examine the concept of social capital and suggest 6 types of it following by the anthropologic concept of 'reciprocity' as well as to provide fruitful discussions on the introduction of social capital variables to System Dynamics modeling of sustainable development. Conclusively, the introduction of social capital to the integration models of environment-economy-society should be based on strongly understanding the social networks, individual identities, and local particularities of the relevant localities in order to enhance the structural validity and applicability of sustainable development models in System Dynamics.

• Korean System Dynamics Review
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• v.7 no.2
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• pp.121-132
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• 2006

A container terminal should concentrate on efficient terminal operation in the long view and analyze an effect through introduction of hi-technology, automated equipments and intelligent information system, when they want to improve their reliability and competitive power in intense global competition. To do this, first this study finds out factors which affect competitive power of a container terminal, and relation between them. And then we used System Dynamics method to analyze an effect according to a value fluctuation of the factors in the long term.

• Korean System Dynamics Review
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• v.7 no.1
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• pp.147-172
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• 2006

With the purpose of long-range planning toward local/regional sustainable development, it is desired to avoid unconditional industrialization and expansion and to build an eco-oriented development strategy considering site-specific characteristics of the environment. This paper thus aims at the elaboration of a system dynamics model of a locality/region so as to understand inherent dynamics of sustainable development and to assess the effectiveness of such an eco-oriented strategy. The model thus consists of several positive and negative feedback loops that accelerate or restrict local/regional economic growth within a system boundary incorporating the environment, economy, and society. The model is moreover applied to the assessment of the effectiveness of the development plan recently established in Damyang in JeollaNamdo, Korea. It is regarded in this case to be effective for population immigration and economic prosperity to give priority to restore the bamboo ecosystem and nourish a series of eco-friendly industries based on the bamboo items developed recently. It is also to be positive to sustainable development since it enables to maintain high quality of the environment from the outset of their development steps.

• Journal of the Korean Operations Research and Management Science Society
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• v.3 no.2
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• pp.75-90
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• 1978

The objective of this paper is to demonstrate how System Dynamics Approach may be used to develop new ways of analyzing and projecting manpower requirements and resources. For this purpose, a System Dynamics Model is presented as an example. An examination of the model will show that a System Dynamics modeling approach is an innovative and useful tool for manpower policy analysis and planning. Second, with minor modifications, the model may be used for manpower policy analysis and planning for any skilled personnel in Korea. For example, a similar model nay be built for engineers to analyze the effects of alternative policies about engineering education, sur as the number of available places in the various institutions of training, scholarships and loans, and the duration of training. An engineer's model may also be used to make the projections of the supply and requirements of engineers in the future according to various alternative assumptions where each assumption represents a policy option.