• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.197-200
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• 1998

Three switched-capacitor(SC) networks are presented including series-parallel capacitor set, reversed-switched-capacitor network and push-pull switched-capacitor network, the performances of which are discussed. Combining the SC networks with traditional DC-DC converters, we form several new topologies. Experiment and analyzed results show that the behavior of a DC-DC converter with large voltage ratio can be improved. A wider voltage conversion range is also obtained.

• Journal of Magnetics
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• v.19 no.1
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• pp.37-42
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• 2014

The equivalent model of a permanent magnet (PM) plays an important role in electromagnetic system calculation. A type of subsection model for a PM bar is established, to improve the accuracy of the traditional equivalent circuit method. The mathematical expression, and its end verification condition, are presented. Based on the analytical method and finite element method, the leakage permeance calculation of a PM bar in an open magnetic circuit is investigated. As an example, for a given certain type of PM bar, the magnetic flux of each section is validated by experiment, and by simulation. This model offers a foundation for building a high accuracy equivalent magnetic PM model in an electromagnetic system.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10b
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• pp.48-53
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• 1993

In this paper, it is shown that chaotic nonlinear chemical process can be controlled based on the Poincare map based control algorithm. An isothermal autocatalytic CSTR, which has chaotic dynamics, is successfully controlled and period 2 orbit is generated in a normal chaotic region with small perturbation of the control parameter.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10b
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• pp.312-315
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• 1993

Optimal control theories based on the maximum principles have been evolved and applied to distributed parameter systems(DPSs) represented by partial differential equations (PDEs) and integral equations (IEs). This paper intends to show that an optimal control of a tubular reactor described by a one-dimensional partial differential equation was obtained using the distributed parameter control method for parabolic PDEs. In develping an algorithm which implements the calculation, the method of lines (MOL) was adopted through using a package called the DSS/2. For the tubular reactor system chosen for this paper, the optimal control method based on PDEs with the numerical MOL showed to be more efficient than the one based on IEs.

• Journal of Magnetics
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• v.19 no.4
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• pp.378-384
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• 2014

Optimization design and robust design are significant measures for improving the performance and reliability of electromagnetic devices (EMDs, specifically refer to relays, contactors in this paper). However, the implementation of the above-mentioned design requires substantial calculation; consequently, on the premise of guaranteeing precision, how to improve the calculation speed is a problem that needs to be solved. This paper proposes a new method for establishing an approximate model for the EMD. It builds a relationship between the input and output of the EMD with different coil voltages and air gaps, by using a user-defined interpolating function. The coefficient of the fitting function is determined based on a quantum particle swarm optimization (QPSO) method. The effectiveness of the method proposed in this paper is verified by the electromagnetic force calculation results of an electromagnetic relay with permanent magnet.

• Journal of Korean Society for Quality Management
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• v.24 no.3
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• pp.1-18
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• 1996

The purpose of this study is to empirically examine the role of supplier relationships as a means of enhancement of quality. The model for this study consists of four groups of concepts - 1) goal of quality, as 2) measures of supplier relationships, supplier assistance and buyer supplier communication, 3) the level of automation and technology, as 4) measures of performance, reliability quality and performance quality. By statistical analysis, the results are as follows. First, the goal of quality positively influences the level of automation, technology, supplier assistance and supplier communication. Second, the level of technology has a positive effect on supplier assistance and supplier communication on the level of automation. Third, the level of automation and technology positively influence the reliability quality. Fourth, supplier assistance and buyer-supplier communication has a positive effect on the reliability and performance quality. These results reveal three paths of supplier relationships in systems for the enhancement of quality.

• Journal of Power Electronics
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• v.11 no.1
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• pp.28-36
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• 2011

In this paper, a three phase cycloconverter type high frequency AC link inverter is discussed. The configuration consists of a high frequency full-bridge inverter and a high frequency transformer followed by a three phase cycloconverter whose switch is composed of anti-series connected MOSFETs with a common source. A simple digital control strategy based on space vector modulation (SVM) and repetitive control for the cycloconverter is proposed although its input voltage is a high frequency AC pulse. The operation principle of the proposed control strategy is analyzed and the equivalent working modes during one interval are also presented. The effectiveness of the proposed control strategy is verified through Matlab/Simulink simulations and experiments on a 1.45kW prototype.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.10a
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• pp.433-436
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• 2000

우편물 자동구분 처리의 범위를 확장시키기 위하여 집배원의 배달순서로 구분하기 위한 방법이 요구된다. 이는 우편 자동구분처리를 위하여 우편봉투에 인쇄된 주소 및 우편번호를 인식하고 이에 대응하는 자동구분정보를 우편물상에 바코드 인쇄하고 판독하여 구분하게 된다. 또한, 다량우편 이용자들에 의하여 우편물 상에 고객 바코드가 사전에 인쇄된 경우에는 바코드를 판독하여 구분한다. 본 논문에서는 우편물 자동구분 처리를 위하여 적용될 4-state 바코드에 정보수록 밀도를 향상시키기 위한 방법을 적용한 것이다. 시험 결과에 의하면, 4-state 바코드의 정보수록밀도는 기존의 16.67% 보다 약 27.79% 향상시킬 수 있었다.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.10a
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• pp.437-440
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• 2000

기계 구분이 어려워 집배원의 수작업 구분에 의존하던 우편물의 배달순로 작업을 인식 기술과 자동 처리 기술의 발달로 인하여 세계 각국은 우편번호에 배달개소를 표현 할 수 있는 코드로 확장하여 배달순로 구분 자동화틀 시도하고 있다. 우편물 순로구분을 위한 주소코드 연구는 국가별 순로구분 자동화 현황에 대한 분석하고 우리나라의 사용하는 우편번호와 주소 지번 체계의 분석을 통하여 우편물 구분 적합한 주소코드와 순로코드를 설계하고 주소코드를 이용한 우편물 처리방법을 제시하였다.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.9 no.3
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• pp.185-190
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• 2009

A scheme of expert system based on iterative learning control is proposed. Iterative learning control can obtain control experience from the historical data to build the knowledge base of expert system. Considering some uncertain factors, a flexible measure is adopted in iterative learning control (ILC). Simulation proves the feasibility and effect of the air conditioning control expert system based on flexible iterative learning control (F-ILC). Finally, a feedback compensation unit is incorporated against irregular heavy disturbance.