• Journal of Institute of Control, Robotics and Systems
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• v.16 no.2
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• pp.151-157
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• 2010

This paper presents the modelling of an MR damper system through extensive experimental studies. The hysteresis of the MR damper is modelled by using the improved Bouc-wen model. A test bed for experimental studies of measuring parameters of the MR damper is designed and implemented. Based on the experimental data, the Bouc-Wen Model is modified for the MR damper system. To check the modelling property, a vehicle suspension system is controlled using a PID controller for the verification of the MR damper model.

• Advances in robotics research
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• v.1 no.1
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• pp.61-79
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• 2014

This paper presents theoretical and experimental investigations into the dynamic modelling and characterisation of a two-link flexible manipulator incorporating payload. A planar two-link flexible manipulator that moves in a horizontal plane is considered. A dynamic model of the system is developed using a combined Euler-Lagrange and assumed mode methods, and simulated using Matlab. Experiments are performed on a lab-scaled two-link flexible manipulator for validation of the dynamic model and characterisation of the system. Two system responses namely hub angular position and deflection responses at both links are obtained and analysed in time and frequency domains. The effects of payload on the dynamic characteristics of the flexible manipulator are also studied and discussed. The results show that a close agreement between simulation and experiments is achieved demonstrating an acceptable accuracy of the developed model.

• Coupled systems mechanics
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• v.12 no.5
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• pp.461-479
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• 2023

The paper deals with the finite element modelling of the free vibration and structural behavior of a particular four-floor reinforced concrete structure subjected to static equivalent seismic loads and supported by a shallow foundation system called SNSF (Spider Net System Footing). The two FE models are a simple 2D Matlab model and a detailed 3D model based on solid elastic elements using Altairworks (Hypermesh and Optistruct). Both models can simulate the soil structure interaction. We concentrate on the behavior of a representative cell involving two columns on five levels. The influence of the boundary conditions on the external vertical planes of the domain are duly studied. The Matlab model appears relevant for a primary estimation of frequencies and stiffness of the whole structure under vertical and lateral loads.

• The Transactions of the Korea Information Processing Society
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• v.5 no.3
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• pp.662-670
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• 1998

In order to overcome the problems with first generation expert systems at the symbol level, recently various knowledge level development techniques of second generation expert systems have been proposed. But, these techniques are conceptual modelling techniques. This paper modifies and complements these conceptual modelling techniques and proposes a Task Object Modelling (TOM) technique as a practical knowledge level expert system development technique. This paper defines a Task Object(TO) as a knowledge unit consisted of a goal, execution conditions, behaviour knowledge, and so on. And, we define a Task Object Diagram(TOD) to depict structual, dynamic, and functional aspects of TO easily. We also define Inference Types as basic units to describe behaviour knowledge of TOs. In order to utilize the proposed TOM technique as not a simple conceptual modelling technique but a practical second generalion expert system development technique, we implement a TOD editor, a TO editor, and TO processing algorithm based on the state of TOs. Also we implement a Inference Types Library, in which each inference type is corresponded to an IRE(Jntelligent Rules Element) method, to transform the defined inference types into IRE methods automatically.

• Journal of the Korean Society of Mechanical Technology
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• v.13 no.2
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• pp.45-54
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• 2011

A vehicle suspension system performs two functions, the ride quality and the stability, which conflict with each other. Among the various suspension systems, an active suspension system has an external energy source, from which energy is always supplied to the system for continuous control of vehicle motion. In the process of the linearization for the nonlinear active suspension system, the frequency dependent damping method is used for the exact modelling to the real model. The pressure control valve which is controlled by proportional solenoid is the most important component in the active suspension system. The pressure control valve has the dynamic characteristics with 1st order delay. Therefore, It's necessary to adopt the lead compensator to compensate the dynamics of the pressure control valve. The sampling time is also important factor for the control performances. The sampling time value is proposed to satisfy the system performances. After the modelling and simulation for the pressure control valve and vehicle dynamic, the performances of the vehicle ride quality and the stability are enhanced.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.195-199
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• 2015

Many conventional management methods have emphasized the minimization of required resources along the supply chain. Accordingly, this paper presents a proposed method called the Virtual Design and Construction (VDC)-aided system. It is based on object-oriented resource control, in order to accomplish a feed-forward control monitoring supply chain logistics. The system is supported by two main parts: (1) IT-based Technologies; and (2) VDC Models. They enable the system to convey proactive information from the detection technology to its linked visualization. The paper includes a field study as the system's pre-test: the Scaffolding Works in a LNG Mega Project. The study demonstrates a system of real-time productivity monitoring by use of the RFIDbased Mobile Information Hub. The on-line 'productivity dashboard' provides an opportunity to display the continuing processes for each work-package. This research project offers the observed opportunities created by the developed system. Future work will entail research experiments aimed towards system validation.

• Journal of Biomedical Engineering Research
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• v.8 no.2
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• pp.245-254
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• 1987

A tuning method for the conventional PID controller in a two-input two-output multivariable system presented. The system is assumed to be no disturbances and modelling errors. Simulation studies show that controller can provide excellent tuning for highly interacting or unfavorable processes.

• Journal of the Korea Computer Industry Society
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• v.4 no.4
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• pp.509-516
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• 2003

Smaller enterprises begin on practical use to form integrated informational system on the inside of company according to development of internet and information techniques. The past days, it was managed mainly information system for the inside of enterprise, but in the present time, e-business between enterprise and enterprise, enterprise and customer, country and enterprise, ERP system, etc are activated. To construct the integrated informationalized system, smaller enterprices use the informational process strategy methods to analyze and evaluate the level of enterprise, construct the information infra and informationalized system. In this paper, 1 introduce the informationalized process strategy method about implimentation of the integrated informationalized system for smaller enterprice, do the modelling for one smaller enterprice by proposed method.

• Journal of Astronomy and Space Sciences
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• v.24 no.1
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• pp.31-38
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• 2007

We have investigated the evolutionary status of 85 Peg within the framework of standard evolutionary theory. 85 Peg has been known to be a visual and spectroscopic binary system in the solar neighborhood. In spite of the accurate information of the total mass (${\sim}1.5M_{\odot}$) and the distance (${\sim}12pc$) from the HIPPARCOS parallax, it has been undetermined an individual mass, therefore the evolved status of the system. Moreover, the coupled uncertainties of chemical composition and age, make matters worse in predicting an evolutionary status of the system. Nevertheless, we computed the various possible models for 85 Peg, and then calibrated stellar parameters by adjusting to the recent observational data. Our modelling computation has included recently updated input physics and stellar theory such as opacity, equation of state, and chemical diffusion. Through a statistical assessment, we have derived a confident parameter set as the best solution which minimized $X^{2}$ within the observational error domain. Most of all, we found that 85 Peg is not a binary system but a triple system with an unseen companion 85 Peg $B_{b}\;{\sim}0.16M_{\odot}$. The aim of the present paper is (1) to provide a complete modelling of the stellar system based on the evolutionary theory, and (2) to constrain the physical dimensions such as mass, metallicity and age.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.4
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• pp.58-67
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• 2003

An automotive engine cooling system is closely related with overall engine performances, such as reduction of fuel consumption, decrease of air pollution, and increase of engine life. Because of complex reaction between each component, the direct experiment, using a vehicle, takes high cost, long time, and slow response to the system change. Therefore, a computer simulation would provide the designer with an inexpensive and effective tool for design, development, and optimization of the engine cooling system over a wide range of operating conditions. In this work, it has been predicted the thermal performance of the engine cooling system in cases of stationary mode, constant speed mode, and city-drive mode by mathematical modelling of each component and numerical analysis. The components are engine, radiator, heater, thermostat, water pump, and cooling fans. Since the engine model is the most important, that is divided into eight sub-sections. The volume mean temperature of eight sub-sections are simultaneously calculated at a time. For detail calculation, the radiator and heater are also divided into many sub-sections like control volumes in finite difference method. Each sub-section is assumed to consist of three parts, coolant, tube with fin, and air. Hence it has been developed the simulation program that can be used in case of design and system configuration changes. The overall performance results obtained by the program were desirable and the time-traced tendencies of the results agreed fairly well with those of actual situations.