• 제목/요약/키워드: Over-Design

검색결과 8,796건 처리시간 0.04초

Design Consideration of Half-Bridge LLC Resonant Converter

  • Choi, Hang-Seok
    • Journal of Power Electronics
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    • 제7권1호
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    • pp.13-20
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    • 2007
  • LLC resonant converters display many advantages over the conventional LC series resonant converter such as narrow frequency variation over wide range of load and input variation and zero voltage switching even under no load conditions. This paper presents analysis and design consideration for the half bridge LLC resonant converter. Using the fundamental approximation, the gain equation is obtained, where the leakage inductance in the transformer secondary side is also considered. Based on the gain equation, the practical design procedure is investigated to optimize the resonant network for a given input/output specifications. The design procedure is verified through an experimental prototype of the 115W half-bridge LLC resonant converter.

Seismic performance evaluation for steel MRF: non linear dynamic and static analyses

  • Calderoni, B.;Rinaldi, Z.
    • Steel and Composite Structures
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    • 제2권2호
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    • pp.113-128
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    • 2002
  • The performance of steel MRF with rigid connections, proportioned by adopting different capacity design criteria, is evaluated in order to highlight the effectiveness of static non-linear procedure in predicting the structural seismic behavior. In the framework of the performance-based design, some considerations are made on the basis of the results obtained by both dynamic time histories and push-over analyses, particularly with reference to the damage level and the structure ability to withstand a strong earthquake.

전복방지를 위한 가변 구조 이동 로봇의 설계와 구현 (Design and Implementation of a Mobile Robot with a Variable Structure for Tip-over Prevention)

  • 이성민;박정길;박재병
    • 제어로봇시스템학회논문지
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    • 제21권4호
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    • pp.356-360
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    • 2015
  • In this paper, we design and implement a mobile robot with variable structure for tip-over prevention. The mobile robot is designed for the purpose of stable drive and work in outdoor terrain. The outdoor terrain is rough and uneven. In this terrain, the tip-over of the mobile robot can occur while driving and working. Therefore, the structure of the mobile robot must be designed in consideration of stable drive and work. The proposed structure is defined as an X-shape for overall balance of the mobile robot. The shape is designed by using a multi-level structure for reducing the size of the robot. To verify the effectiveness of the proposed design, we analyze the tip-over characteristics according to the height of gravitational center and the extension length of the robot. Finally, we develop a prototype of the mobile robot with variable structure, taking the results of the tip-over analysis into consideration.

On Slope Rotatability of Central Composite Designs of the Second Type

  • Kim, Hyuk-Joo;Ko, Yun-Mi
    • Communications for Statistical Applications and Methods
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    • 제11권1호
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    • pp.121-137
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    • 2004
  • Kim(2002) proposed a second type of central composite design (CCD2), in which the positions of the axial points are indicated by two numbers. In this paper, we study properties of CCD2 when we are interested in estimating the slope of a response surface. Conditions are obtained for CCD2 to be slope-rotatable over axial directions, and some CCD2's are presented that have slope rotatability over axial directions. Also values of a measure of slope rotatability over axial directions are tabulated for various CCD2's. Finally, it is shown that CCD2 is always slope-rotatable over all directions.

한스 J. 웨그너 의자디자인 특성에 관한 연구 (A Study on the Characteristics of Chair Design by Hans J. Wegner)

  • 김상권
    • 한국가구학회지
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    • 제28권4호
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    • pp.314-325
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    • 2017
  • Hans Wegner, one of the legendary designers who led the 20th century Nordic modern design, is a representative furniture designer of Danish Modern. His beautiful proportions, elaborate structure, lightweight and simple chairs show the essence of Danish modernism for mass production. Designed and built over 500 chairs, he demonstrated the essence of chair design through a fully structured prototype. He shows his passion and craftsmanship as a designer through over 1000 designs. In addition, chair design shows the value of timeless design and is loved by modern times. Therefore, this study aims to study the characteristics of chair design by Hans Wegner and to help furniture design education by analyzing design, structure, function and material.

체계적인 헬리콥터 내추락성 설계개념 연구 (A Study on the Systematic Crashworthiness Design Concept)

  • 황정선;정재권;현영오
    • 항공우주시스템공학회지
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    • 제7권2호
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    • pp.35-41
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    • 2013
  • Crashworthiness design concept in the helicopter development is still under evolutionary stage. Survivability in the event of a crash was remarkably improved and this fact can be recognized by the analysis results on the AH-64 Apache and UH-60 Black Hawk crash accidents. Those two models are the first ones in which the crashworthiness design concept was applied with a full-scale requirement. Here we need to notice that under-design of the system results in unexpected injuries and deaths while over-design of the crashworthy elements result in unnecessary weight and costs. If landing gear system would be verified to have enough energy absorption capability in the specified vertical velocity interval, then design requirements of the airframe, fuel system and seats could be modified positively. In this paper, the right and systematic crashworthiness design concept is reviewed on the assumption that design requirements of some crashworthy elements could be partially tailored.

마그네트 천장크레인의 최적설계와 직교배열을 이용한 민감도 분석 (The Optimum Design of Magnet Over Head Crane and the Sensitivity Analysis for Orthogonal Array)

  • 노영희;홍도관;최석창;안찬우;한근조
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 춘계학술대회 논문집
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    • pp.786-790
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    • 2002
  • In this study, structural optimum design was applied to the girder of magnet over head crane. The optimization was carried out using ANSYS Code for the deadweight of girder, especially focused on the thickness of its upper, lower, side and reinforced plates. The weight could be reduced up to around 15% with constraints of its deformation, stress, natural frequency and buckling strength. The structural safety was also verified by the buckling analysis of its panel structure. It might be thought to be very useful to design the conventional structures for the weight save through the structural optimization. The objective function and restricted function were estimated by the orthogonal array, and the sensitivity analysis of design variable fur that was operated.

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IC 카드를 위한 polynomial 기반의 타원곡선 암호시스템 연산기 설계 (Design of Elliptic Curve Cryptographic Coprocessor over binary fields for the IC card)

  • 최용제;김호원;김무섭;박영수
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(2)
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    • pp.305-308
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    • 2001
  • This paper describes the design of elliptic curve cryptographic (ECC) coprocessor over binary fields for the If card. This coprocessor is implemented by the shift-and-add algorithm for the field multiplication algorithm. And the modified almost inverse algorithm(MAIA) is selected for the inverse multiplication algorithm. These two algorithms is merged to minimize the hardware size. Scalar multiplication is performed by the binary Non Adjacent Format(NAF) method. The ECC we have implemented is defined over the field GF(2$^{163}$), which is a SEC-2 recommendation[7]..

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