• Journal of Electrical Engineering and Technology
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• v.7 no.2
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• pp.225-229
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• 2012

This paper proposes a reduced-scale simulator that can replace numerical analytic methods for the estimation of potential distribution caused by ground faults in various grounding systems. The simulator consists of a hemispherical electrolytic tank, a three-dimensional potential probe, a grounding electrode, and a data acquisition module. The potential distribution is measured using a potentiometer with a position-tracing function when a test current flows to the grounding electrode. Using the simulator, we could clearly analyze the potential distribution for a reduced- scale model by one-eightieth of the buried depth and length of the grounding rod and grounding grid. Once both the shape of the grounding electrode and the fault current are known, the actual potential distribution can be estimated.

• Fire Science and Engineering
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• v.31 no.4
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• pp.43-51
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• 2017

In this study, new design fire curves were suggested for the utilization in fire simulations. Numerical simulations with the Fire Dynamics Simulator (FDS) were performed for the n-octane and n-heptane pool fires in the ISO 9705 compartment to evaluate the prediction performance of the previous quadratic, exponential design fire curves and newly suggested ones. The numerical results were compared with the experimental temperature and concentrations of $O_2$ and $CO_2$. The numerical results with the previous quadratic and exponential curves showed slow increase and decrease trend than experiments. However, the numerical results with the newly suggested 2 design fire curves showed more similar variation trend in temperature, $O_2$ and $CO_2$ concentrations than the quadratic and exponential curves. It was found that the newly suggested design fire curves can be possibly used in the numerical simulation of fires in a practical respect.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1109-1114
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• 2007

This paper presents the road simulator control technology for reproducing the road input signal to implement the real road data. The simulator consists of the hydraulic pump, servo valve, hydraulic actuator and its control equipment. The QFT is utilized to control the simulator effectively. The control system illustrates a tracking performance of the closed-loop controller with low order transfer function G(s) and pre-filter F(s) for a parametric uncertain model. A force controller is designed to communicate the control signal between simulator and digital controller. The efficacy of the QFT force controller is verified through the numerical simulation, in which combined dynamics and actuation of the hydraulic servo system are tested. The simulation results show that the proposed control technique works well under uncertain hydraulic plant system. The conventional software (Labview) is used to make up for the real controller in the real-time basis, and the experimental works show that the proposed algorithm works well for a single road simulator.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.11
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• pp.1069-1076
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• 2007

This paper presents the road simulator control technology for reproducing the road input signal to implement the real road data. The simulator consists of the hydraulic pump, servo valve, hydraulic actuator and its control equipment. The QFT(Quantitative Feedback Theory) is utilized to control the simulator effectively. The control system illustrates a tracking performance of the closed-loop controller with low order transfer function G(s) and pre-filter F(s) for a parametric uncertain model. A force controller is designed to communicate the control signal between simulator and digital controller. Tracking specification is satisfied with upper and lower bound tolerances on the steep response of the system to the reference signal. The efficacy of the QFT force controller is verified through the numerical simulation, in which combined dynamics and actuation of the hydraulic servo system are tested. The simulation results show that the proposed control technique works well under uncertain hydraulic plant system. The conventional software (Labview) is used to make up for the real controller in the real-time basis, and the experimental works show that the proposed algorithm works well for a single road simulator.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.191-191
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• 2000

Hydraulic servo system is difficult to be made up and each component is very expensive, it takes long for actual system to make and test and it costs a high price. Because of these characteristics of hydraulic servo system, a real time simulator that could describe behavior of real system is highly demanded, without composing real hydraulic system. So, many studies have been (lone on these subjects and many simulators are developed with superiority. Since the nonlinearity of a hydraulic system common simulator have composed of many calculative times byusing DSP(Digital Signal processing) and have made it possible to find the situations of the system in real time, calculating hydraulic simulation and controller separately. In this study, we suggest real-time simulator that could describe real system without ordinary DSP card. This simulator is composed of 80196kc and personal computer. DSP card that has calculated complex numerical equation is supplanted by personal computer and 80196kc generates control signals independently out of the personal computer. In all process, personal computer is synchronized with one-board microprocessor within sampling time in the closed loop system. This makes it possible to be described in hydraulic servo system in real time. And to make a comparison between the result of the real-time simulator and a hydraulic servo system.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1999.03a
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• pp.213-218
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• 1999

• International Journal of Precision Engineering and Manufacturing
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• v.4 no.1
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• pp.9-14
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• 2003

In this study we suggest real-time simulator that could describe rent system without ordinary DSP card. This simulator is composed of 80196kc-16bit ordinary microprocessor, which is widely used up to now and personal computer. DSP card that has calculated complex numerical equation is replaced by personal computer and 80196kc generates control signals independently out of the personal computer. In all process personal computer is synchronized with one-board microprocessor (80196kc) within sampling time in the closed loop system. This makes it possible to be described in hydraulic servo system in real time.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.172-178
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• 2007

The purpose of Railroad Vehicles License Management in accordance with the Railroad Safety Law is to improve the quality of railroad safety. And the train simulators come into use for training of train operation and testing to issue Railroad Vehicles License. So, It is very important that the simulators for the Railroad Vehicles License Test require to work correctly, to measure driver's operation quality in numerical system and to ensure the justice of license test. In fact, nobody can guarantee that the simulators are feasible performance to use in license test. The simulator for train driver license test can be used effectively for studying of needed performance and quality to test new driver's skill. This study hopefully provides the base for improving the quality of the simulator for train driver's license test and contributes furthermore to improve the simulator development technology and railroad safety.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.9
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• pp.397-407
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• 2002

A new simulator which predicts the quantum effect in NMOSFET structure is developed. Using the self-consistent method by numerical method, this simulator accurately predicts the carrier distribution due to improved calculation precision of potential in the inversion layer. However, previous simulator uses analytical potential distribution or analytic function based fitting parameter Using the developed simulator, threshold voltage increment and gate capacitance reduction due to the quantum effect are analyzed in NMOS. Especially, as oxide thickness and channel doping dependence of quantum effect is analyzed, and the property analysis for the next generation device is carried out.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2480-2482
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• 2003

As make a simulator including user interface functions like start & stop, load parameters, record and save, view 3D display has a real-like length and numerical value of sizes, represent real-shape of inner and outer part of robot, make the possible fast and slow selective observation as a adjust a step, receiving the images through the image device which attached in robot, so make a motion tester simulator of humanoid robot which coded by windows based GUI(Graphic User Interface) program with a MMI(Man Machine Interface) function that user can watch the environment which included robot and use a images. For implement this, we use a design data that converted data which made by use a CAD for Laser RP(Rapid Prototyping) progress into C coding for simulator programming. Using OpenGL, an API of graphic, it has a efficiency and detail of graphic operation. To make and test animation data, it has the option of save and resume in animation.