• IE interfaces
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• v.13 no.3
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• pp.348-357
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• 2000

SCM(Supply Chain Management) is a new approach to satisfy customers via an integrated management for the whole business processes of the manufacturing from the raw material procurement to the product or service delivery to customers. Typically the semiconductor industry is the one whose supply chain network is distributed all over the world, and its manufacturing process has the particular characteristics which has to be considered in the modeling of supply chain. In this paper we suggest the push and pull type supply chain models based on the manufacturing characteristics and their mathematical formulation for the semiconductor industry. Push supply chain model pursuits the high throughput and the balance of the WIP flow, and pull supply chain model does to minimize the total cost of order-based manufacturing, distribution and transportation process in order to meet customer's request appropriately.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.364-367
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• 2000

This paper describes a Push-Pull type high fre-quency resonant inverter conposed of consolidation of boost converter circuit and resonant circuit. By using a boost converter circuit the proposed inverter can obtain a twice input voltage of reson ant circuit and reduce a secondary turn ratios. By using both boost-converter and switching device can be reduce by half. Also the ana-lysis of the proposed circuit was described by using normalized parameter and operating characteristics have been evaluated as to switching frequency and parameters. In the future this pro-posed inverter shows that it can be practically used as a power source system for the lighting equipment of discharge lamp induction heating applications.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.489-492
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• 2000

A novel low-cost simple and unity-power-factor electronic ballast is presented. The proposed electronic ballast employs a bypassing capacitor and load networks composed of ballast capacitors and small charge pump capacitors as power factor correction circuit combined with the secondary winding of the transformer in the self-excited current-fed push-pull resonant inverter(CF-PPRI) resulting in cost-effectiveness and higher efficiency. By analyzing the principles of power factor correction mathematically optimum design guidelines are presented. Since the lamps are used in power factor correction stage the input power is automatically adjusted according to the number of the lamps.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.11 no.4
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• pp.100-108
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• 1997

A combined buck and boost push-pull quantum series resonant rectifier(PPQSRR) is newly proposed to achieve a power factor correction without start-up inrush current. Based on the developed dynamic modeling of the proposed rectifier, an inrush current elimination control technique is proposed and the usefullness of the proposed rectifier and control method are verified by computer simulation and experimental results. With the proposed control method, a high power factor and wide range of output voltage can be obtained.

• Proceedings of the KIPE Conference
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• 2009.11a
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• pp.149-151
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• 2009

본 연구는 다른 에너지원에 비해 출력전류가 커짐에 전압의 드랍이 심한 에너지원을 대상으로하며, 기존의 고효율특성을 갖는 공진형 컨버터가 듀티의 변화에 자유롭지못한 단점을 보안하기위해 캐패시터를 이용하여 기존의 공진형 Push-Pull 컨버터와 부분전압제어가 가능한 Boost컨버터 2대를 결합하여 입력전압의 변화에도 일정한 DClink전압이 형성되도록 하고 있다. 각각 컨버터의 출력전압은 입력전압에 따라 변동하지만 고효율을 위하여 공진형 컨버터부에서 전압할당이 크도록 구성 되었으며, 본 논문은 공진형 Push-Pull컨버터, Boost 컨버터의 동작원리 및 2대의 컨버터를 결합구성 할 경우의 전력의 분담 및 전체적인 제어원리를 다루며, 시뮬레이션을 통하여 이를 입증하고자 한다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.10a
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• pp.138-140
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• 2005

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.62 no.1
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• pp.45-49
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• 2013

High frequency system has been used for the purpose of skin care and obesity treatment, by high-frequency energy is applied to the human body generates deep heat. Conventional high frequency system could not selection control by depending on the body load fluctuations. Such as burns and side effects have been reported by system instability and then therapeutic effect is insufficient. During treatment, objective information about the status of the patient was no. Because of treatment methods are subjective, and so tailored treatments were impossible. In this paper, high frequency medical system with sinusoidal frequency characteristics without distortion of the Push pull switching scheme for pain relief therapy was designed. And control circuit that was designed by feedback using the output changes according to the body-load fluctuation. Last, power circuit for efficient control the heat generated from the hardware was proposed.

• The Transactions of the Korean Institute of Power Electronics
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• v.8 no.2
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• pp.180-191
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• 2003

In this paper, the modelings of PSPICE of the piezoelectric transformer and CCFL drive circuit using an electrical equivalent circuit is proposed. In the CCFL drive circuit modeling the model parameters of the CCFL were derived using the method of least squares because push-pull inverter and loads such as CCFL were also modeled using PSPICE. It is considered that the simulation techniques can be used in the piezoelectric devices such as piezoelectric transformer.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2006.05a
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• pp.99-104
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• 2006

A semi-Lagrangian finite element scheme with objective time stepping algorithm for solving viscoelastic flow problem is presented. The convection terms in the momentum and constitutive equations are treated using a quasi-monotone semi-Lagrangian scheme, in which characteristic feet on a regular grid are traced backwards over a single time-step. Concerned with the generalized midpoint rule type of algorithms formulated to exactly preserve objectivity, we use the geometric transformation such as pull-back, push-forward operation. The method is applied to the 4:1 planar contraction problem for an Oldroyd B fluid for both creeping and inertial flow conditions.

• Korean Journal of Computational Design and Engineering
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• v.5 no.2
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• pp.184-195
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• 2000

MDO (Multidisciplinary Design Optimization) methodology is an emerging new technology to solve a complicate structural analysis and design problem with a large number of design variables and constraints. In this paper MDO methodology is adopted through the use of computer aided systems such as Geometric Solid Modeller, Mesh Generator, CAD system and CAE system. And this paper introduces MDO methodology as a new method for structural analysis and design through the application to the structural design of flap drive system. In a MDO methodology application to the structural design of flap drive system, kinetodynamic analysis is done using a simple aerodynamic analysis model for the air flow over the flap surface instead of difficult aerodynamic analysis. Simultaneously the structural static analysis is done to obtain the optimum structural condition. And the structural buckling analysis for push pull rod is also done to confirm the optimum structural condition (optimum cross section shape of push pull rod).