• 한국생산제조학회지
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• 제7권3호
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• pp.110-117
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• 1998

A continuum-based configuration design sensitivity analysis method is developed for kinematically driven mechanical systems. The configuration design variable for mechanical systems is defined. The 3-1-3 Euler angle is employed as the orientation design variable. Kinematic admissibility conditions of configuration design change. Direct differentiation method is used to derive the governing equations of the design sensitivity. Numerical examples are presented to demonstrate the validity and effectiveness of the proposed method.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.238-238
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• 2010

This paper describes the design and analysis of vibration driven energy harvester for low frequency. The maximum output powers at load were $124.2{\sim}132.2\;{\mu}W$ with magnets during 3 mm input displacement at 6 Hz resonant frequency of system.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2000년도 가을 학술발표논문집 Vol.27 No.2 (1)
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• pp.367-369
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• 2000

소프트웨어 설계 단계에서 기능성(functionality)과 더불어 비기능성 (non-functionality)에 관한 고려가 매우 중요하다. 그럼에도 불구하고 비기능성 고유의 복잡성으로 인해 두가지를 함께 해결하기는 매우 어려운 문제였고, 비기능성을 구현하는데 많은 난점이 있어왔다. 우리는 이러한 문제를 해결하기 위해 기능성의 유지를 보장하는 소프트웨어 수정 방법인 재구성(refactoring)에 착안하였다. 이를 사용하여 기능성과 독립적으로 비기능성을 획득하도록 설계를 수정할 수 있도록 도와주는 체계적인 비기능성 기반 디자인 재고성(Nonfunctionality-driven Design Refactoring)을 제안한다. 또한 우리가 제시한 방법을 간단한 웹 쇼핑몰 시스템 예제에 적용하여 확장성이 증가하도록 디자인 재구성을 하여 본다.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1993년도 Fifth International Fuzzy Systems Association World Congress 93
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• pp.985-988
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• 1993

An alternative approach to the design of application-driven fuzzy systems is proposed. A broad class of fuzzy systems applications requires a certain fuzzy partition of the input space while it demands for simple numerical quantities. For this class, a dedicated fuzzy system archictecture is presented and a design strategy is proposed. Both the single-input/single-output and multi-input/multi-output cases are considered. Numerical analysis are complete illustrating several aspects of the proposed framework.

• 토지주택연구
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• 제4권3호
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• pp.279-286
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• 2013

기성 말뚝을 항타시공하는 방법은 시공비가 적게 들면서도 우수한 지지력을 얻을 수 있는 효율적인 시공방법이다. 하지만 국내와 같이 매립층이 많고 다양한 지반조건에서는 예상치 못한 문제로 인하여 기계적 굴착이 수반되는 매입공법으로 변경되기도 한다. 따라서, 항타공법이 매입말뚝에 비하여 불확실성이 더 높을 수 있다. 본 논문에서는 국내에서 건축물의 기초로 사용되고 있는 PHC 항타말뚝의 불확실성 요인을 줄여주고 보다 신뢰성 있는 설계가 가능하도록 하기 위하여 한계상태설계법의 일종인 하중저항계수법(LRFD) 설계정수를 산정하였다. PHC 항타말뚝의 LRFD 설계정수를 제안하기 위해 총 221회(초기동재하 : 93회, 재항타동재하 : 128회)의 동재하시험자료와 이들 말뚝에 대한 지지력 설계(Meyerhof 설계법, SPT-CPT 전환 설계법) 자료를 분석하고 목표 신뢰도 지수 2.33과 3.0에 대해 하중저항계수를 제시하였다. PHC 항타말뚝의 저항계수는 목표 신뢰도 지수에 따라 Meyerhof 방법, SPT-CPT 전환법은 각각 0.43~0.55 및 0.40~0.49를 나타내었다.

• Journal of Power Electronics
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• 제15권3호
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• pp.634-643
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• 2015

This paper presents a high frequency design approach for improving efficiency over a wide load range in the self-driven phase-shifted full-bridge converters for server power systems. In the proposed approach, a detailed ZVS analysis of the lagging leg switches in both the continuous conduction mode (CCM) and the discontinuous conduction mode (DCM) is presented. The optimum dead time and the determination of the appropriate operation mode are given for high efficiency according to the load conditions. Finally, the optimum operation conditions are defined to achieve a high-efficiency. A laboratory prototype operating at 80 kHz, rated 1 kW (12 V-83.3 A), is built to verify proposed theoretical analysis and evaluations. The experimental results show that the maximum efficiency is achieved as 95% and 83.5% at full load and 5% load conditions, respectively.

• Journal of Magnetics
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• 제21권3호
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• pp.393-398
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• 2016

This paper proposes a novel 16/10 segmented rotor switched reluctance motor (SSRM) for belt-driven starter generators (BSGs). Different from conventional SRMs, the stator of the proposed SSRM consists of two types of stator poles, i.e., exciting and auxiliary poles, and the rotor is constructed from a series of discrete segments. The topology and operation principle of this proposed SSRM are illustrated firstly, and then the design rules are listed. In addition, the finite element method (FEM) is employed to get the static and dynamic characteristics of the proposed SSRM. Finally, the simulation results are presented to show the validity of the proposed SSRM for BSGs.

• International Journal of Air-Conditioning and Refrigeration
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• 제14권3호
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• pp.85-93
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• 2006

The present study has been conducted to simulate dynamics of a gas engine-driven heat pump (GHP) for the design of control algorithm. The dynamic model of a GHP was based on conservation laws of mass and energy. For the control of refrigerant pressures, actuators such as an engine throttle valve, outdoor fans, coolant three-way valves and liquid injection valves were controlled by P or PI algorithm. The simulation results were found to be realistic enough to be applied for the control algorithm design. The model could be applied to build a virtual real-time GHP system so that it interfaces with a real controller for the purpose of developing control algorithm.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.197-202
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• 1991

Recently, an output feedback variable structure control scheme(OFVSCS) is proposed to remove the assumption of full state availability and to make the application of VSC scheme to the high order systems with unmeasurable state variables possible. In this paper, a design method of an output feedback variable structure control system (IOFVSCS) that guarantees the invariance of the sliding mode against process parameter variation and external disturbance is proposed. The IOFVSCS is composed of two components; dynamic switching surface driven by measured I/0 informations and switching control input generator driven by switching surface information and measured output, where the two components are constructed by adopting unknown vector modelling approach. The invariance condition for the IOFVSCS is proved to be the same as that of the conventional VSCS. Simulation results show that the IOFVSCS can be designed to have robust properties better than that of the conventional VSCS in spite that the IOFVSCS is driven by small amount of measured information.

• 수산해양기술연구
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• 제51권3호
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• pp.285-294
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• 2015

As a "kind of" mature ship form, planing hull has been widely used in military and civilian areas. Therefore, a reasonable design for planing hull becomes more and more important. For planing hull, resistance and trim are always the most important problems we are concerned with. It affects the planing hull's economic efficiency and maneuverability very seriously. Instead of the expensive towing tank experiments, the development of computer comprehensive ability allows us to previously apply computational fluid dynamics(CFD)to the ship design. In this paper, the CFD method and Goal Driven Optimization (GDO) were used in the estimations of planing hull resistance and running attitude to provide a possible method for performance computation of planing hull.