• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1513-1517
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• 2010

Recently, the important of Progress Management is being emphasized because construction have become more complex and increasingly specialized. The existing progress control method needs to be changed because only numerical information is being provided and is very difficult to understand all poor progress. To resolve these problem, this study suggests a simulation method for progress management by using 4D CAD System because 4D CAD system has effective functions to convert numerical information to visualized information. The suggested simulation method not only are reviewed an application of railway construction but enables managers to understand problems in managing this system for verifying the suggested simulation method.

• Journal of the Korea Society for Simulation
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• v.8 no.4
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• pp.89-107
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• 1999

There are many issues in computer simulation such as verifying model code, validating models, understanding the dynamics of systems and training the personnel. The developers of simulation tool have been interested in the animation since it can help solve the problems related to the above listed issues. In practice, animation is one of the popular method for displaying the simulation output for solving these problems. Trying to display all the graphic objects representing the dynamics of the models being simulated, however, causes the distraction of focus, which results in solving the above listed problems difficult. The redundant graphic objects also Increase the computer computation overhead. This paper presents a hierarchical animation environment in which the users can have better focus on the dynamics of system components. In hierarchical animation environment the users can observe the dynamics of system by selectively choosing the hierarchical level and components with in a level of the hierarchically structured model. Especially when the model is large and complex the selection of observation level is needed. The design approach of the hierarchical animator is based on the DEVS(Discrete Event system Specification) formalism which is theoretically well grounded means of expressing modular and hierarchical models.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.265-266
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• 2008

The interest on harmonics which is one of the matters related with power quality problem is not limited in only the system where the large scale industrial load is connected. The harmonics phenomenon not only causes the malfunction of devices, but also lowers the energy efficiency of power system. This paper focuses on the harmonic analysis process to establish the harmonic mitigation method, considering the harmonics distortion as a major cause to reduce the energy efficiency of a skyscraper. A system diagram of building is modelled with PSCAD simulator. Based on the harmonic analysis results of it, the electrical locations with the high priority to install the mitigating devices are selected. Finally, the result of PSCAD simulations and the site-measured data are compared, verifying that they reach a common conclusion.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.05a
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• pp.357-360
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• 2008

In this paper a high efficiency soft switching boost converter is proposed for photovoltaic system. Using some resonant components, the circuit can be achieved the soft switching capability. Each of the switches in the proposed circuit performs ZV (Zero Voltage) or ZC (Zero Current) switching. Thus, the high efficiency characteristic can also be obtained, and then the size of the total system can be reduced. The operational modes of the verifying the effectiveness of the proposed circuit. As a matter of course, we will present the simulation results in this paper.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1572-1577
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• 2003

The powershift transmission have the advantage of easier operation and higher efficiency by using the hydraulic clutch and mechanical power transfer system. It is important to control the engaging pressure and time. The hydraulic control system is used for these controls of the modulator valve, the accumulator, the sump valve and etc. This study have made a simulator for verifying the pressure characteristic of the shuttle powershift transmission and developed the computer simulation model of the hydraulic components and system by using 'AMESim'. As a result, the design parameters which have an effect on the pressure modulation are verified to the spring stiffness of the modulator valve and the volume of the accumulator.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06a
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• pp.196-198
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• 2006

Shader architecture is one of the fastest growing fields in the ever advancing 3D graphics, and massive amounts of Ideas and technologies are being introduced to the market continuously. In this paper, we present a flexible cycle-accurate simulation environment to accelerate and alleviate the process of developing and verifying these ideas and technologies. Combination of 3D graphics API and hardware simulator allows OpenGL applications to be emulated off-the-shelf for a given shader micro-architecture. Easily modified parameters allow the simulation environment to be tailored to specific demands or requirements.

• Proceedings of the KIEE Conference
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• 2002.11b
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• pp.161-163
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• 2002

Service restoration following a complete or partial collapse starts with reenergizing a transmission line from black-start generators. Voltage problems can arise from Ferranti effect as unloaded transmission line is reenergized. This Paper presents system analyser to develop for verifying the primary restorative transmission system. The algorithm which has been used in the analyser is to handle load pick-up compensating Ferranti effect. and terminal voltage and reactive capability limitation of black-start generators about self-excitation.

• Proceedings of the KIEE Conference
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• 2002.11c
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• pp.365-369
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• 2002

In this paper, DC motor controller has been designed by using SoC. SoC is short for System on a chip. This is a methodology that both a processor and some applications are integrated in a chip. In order to design this system based on SoC, PIC 16C57 has been selected as a processor because it has not too many instruction sets and simple data path named a harvard structure. And motor control module has been programmed by using VHDL. The advantages of the design based on SoC are as follows: simple structure, high speed working, easily verifying and simulating the system.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.05a
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• pp.180-184
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• 2009

A novel set of experimental test tooling for measuring pulling and holding forces for drawbeads on binders inclined at a wide range of angles is introduced. A mechanical design featuring a single load cell, a male-female draw bead set, translation and rotation degrees of freedom, and a screw-driven clamping system has been incorporated into a standard tensile test machine. On a real time basis, restraining and holding force data with respect to draw-in displacement may be directly downloaded into a PC for data processing. The proposed experimental system represents a significant breakthrough in drawbead simulation technology due to its relatively low cost, clever design, and versatility. The system is shown to yield excellent experimental data suitable for verifying theory and numerical model predictions.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2005.05a
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• pp.364-369
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• 2005

In the semiconductor and optical industry the non-contact transportation is required for reducing the damages. The ultrasonic levitation is the solution of the problem. In this paper, the ultrasonic levitation system and 3 disk-type stator for levitation various object are proposed. The vibration modes of disks are analyzed with FEM and designed with the analysis results. The 3D vibration profiles of the disks are measured by Laser scanning vibrometer for verifying the vibration characteristics of the system. The amplitudes of the disks and the levitation heights of object are measured for evaluating the performance.