• Proceedings of the KIEE Conference
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• 2001.10a
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• pp.205-207
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• 2001

In response to this inverter microwave oven has been developed to improve high speed cooking time & energy saving performance. The voltage resonating inverter has a defect in switching element that works at 5 or 6times higher than input voltage. Especially, it is very difficult to choose the switching device is very high for the 220 (V) commercial voltage. In this paper, it is proposed the optimum method to realize the turbo 1200(W) output power for microwave oven that is employed the 900(V) IGBT with decreasing operating voltage of the switching component by making the 220(V), 1000(W) inverter through the active clamp voltage resonating inverter.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2449-2451
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• 2001

The purpose of this paper is to develop image inspection system endows an automatic operating and measuring that the moment values are invariant with respect to variable object size and rotation. In this paper, using these moment feature vector with Hu's 7 invariant moment is also given. The characteristics of section which is applied in the mechanics used moment descriptor of invariant moment detection algorithm for image inspection system. Corresponding rates between 94% and 96% have archived for all object tested.

• Journal of Korea Game Society
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• v.20 no.3
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• pp.65-74
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• 2020

In the shadow map method, if the shadow map is magnified, the shadow has a jagged silhouette. Herein, we propose a soft shadow method that filters reshaped silhouettes analytically. First, the shadow silhouette is reshaped through sub-texel edge detection, which is based on linear or quadratic curve models. Second, an integral shadow filtering algorithm is used to accurately obtain the average shadow intensity from a definite integral estimation. The implementation demonstrates that our solution can effectively eliminate jagged aliasing and efficiently generate soft shadows.

• Journal of Mechanical Science and Technology
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• v.20 no.8
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• pp.1169-1182
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• 2006

Robust design technology has been applied to versatile engineering problems to ensure consistency in product performance. Since 1980s, the concept of robust design has been introduced to numerical optimization field, which is called the robust optimization. The robustness in the robust optimization is determined by a measure of insensitiveness with respect to the variation of a response. However, there are significant difficulties associated with the calculation of variations represented as its mean and variance. To overcome the current limitation, this research presents an implementation of the approximate statistical moment method based on kriging metamodel. Two sampling methods are simultaneously utilized to obtain the sequential surrogate model of a response. The statistics such as mean and variance are obtained based on the reliable kriging model and the second-order statistical approximation method. Then, the simulated annealing algorithm of global optimization methods is adopted to find the global robust optimum. The mathematical problem and the two-bar design problem are investigated to show the validity of the proposed method.

• Wind and Structures
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• v.16 no.4
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• pp.323-340
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• 2013

An active mass damper system for flutter control of bridges is presented. Flutter stability of bridge structures is improved with the help of eccentric rotational actuators (ERA). By using a bridge girder model that moves in two degrees of freedom and is subjected to wind, the equations of motion of the controlled structure equipped with ERA are established. In order to take structural nonlinearities into consideration, flutter analysis is carried out by numerical simulation scheme based on a 4th-order Runge-Kutta algorithm. An example demonstrates the performance and efficiency of the proposed device. In comparison with known active mass dampers for flutter control, the movable eccentric mass damper and the rotational mass damper, the power demand is significantly reduced. This is of advantage for an implementation of the proposed device in real bridge girders. A preliminary design of a realization of ERA in a bridge girder is presented.

• Computers and Concrete
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• v.4 no.1
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• pp.67-82
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• 2007

The discrete crack-concept is applied to study the 3D propagation of tensile-dominated failure in plain concrete. To this end the Partition of Unity Finite Element Method (PUFEM) is utilized and the strong discontinuity approach is followed. A consistent linearized implementation of the PUFEM is combined with a predictor-corrector algorithm to track the crack path, which leads to a robust numerical description of concrete cracking. The proposed concept is applied to study concrete failure during the PCT3D test and the predicted numerical results are compared to experimental data. The proposed numerical concept provides a clear interface for constitutive models and allows an investigation of their impact on concrete cracking under 3D conditions, which is of significant scientific interests to interpret results from 3D experiments.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.931-934
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• 2005

The scalar point multiplication operations is one of the most time-consuming components in elliptic curve cryptosystems. In this paper, we suggest how to induce the point-quadruple (4Q) operation by improving the double-and-add method, which has been a prevailing computing method for calculating the result of a scalar point multiplication. Induced and drived numerical expressions were evaluated and verified by a real application using C programming language. The induced algorithm can be applied to a various kind of calculations in elliptic curve operations more efficiently and by a faster implementation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.11a
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• pp.252-259
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• 1999

This paper describes the development of cluster-aware application that provides advanced services such as automatic failover, faster error recovery, easy administration and scalability in clustering environment. For These, total system architecture and algorithm are proposed. For the verification this paper, socket application and cluster resource DLL, administration DLL for the application are implemented and tested. Using the microsoft cluster server, The individual failed services was relocated from one server to another. The result shows that allows applications on the original server to continue running, unaffected tv the failed service.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.7
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• pp.1520-1526
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• 2003

Design and implementation method or the 100[W] DD/AC invertor using PICl6C711 processor is described in this paper. Especially, fuzzy inference algorithm is involved in this system which can be adaptive to the environment variation. Input/output control and power consumption monitoring is controlled based on PIC16C711 processor, which compute the optimal values acquired from inference engine. Such experimental as function, efficiency, motoring are performed and experimental results showed that monitoring error is less than 2% and widely used in the area of industrial fields.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.331-334
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• 2001

The voltage resonating inverter has a defect in switching element that works at 5 or 6times higher than input voltage. Especially, it is very difficult to choose the switching device is very high for the 220(V)commercial voltage. In this paper, it is proposed the optimum method to realize the turbo 2000(W) power for induction cooker that is employed the 900(V) IGBT with decreasing operating voltage of the switching component by making the 220(V), 1500(W) inverter through the claim mode voltage resonating inverter.