• 제목/요약/키워드: inverse design

검색결과 765건 처리시간 0.033초

원통형 수중운동체 두부 형상 역설계 (An Inverse Design for Nose Shape of a Cylindrical-Shaped Submerged Body)

  • 정철민
    • 한국군사과학기술학회지
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    • 제7권3호
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    • pp.69-76
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    • 2004
  • In this paper, an efficient inverse design method for nose shape of submerged body based on the MGM(Modified Garabedian-McFadden) design method has been developed. The MGM design method is a residual-correction technique, in which the residuals are differences between the desired and the computed pressure distributions. 3-D incompressible Wavier-Stokes equation was adopted for obtaining the surface pressure distribution and combined with the MGM design method to perform the inverse design of nose shape of submerged body. The design method was verified by applying to several airfoil shapes. Improved design shapes could be obtained when the method was applied to nose shapes of submerged body.

2채널 오디오 시스템에서 전달계 변동에 강인한 역필터 설계 기법 (The Method of New Robust Inverse Filter Design in 2-Ch Audio System)

  • 박병욱;김학윤
    • 한국컴퓨터정보학회논문지
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    • 제13권1호
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    • pp.185-192
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    • 2008
  • 2개 이상의 스피커로 오디오 신호를 재생할 경우에 발생하는 가장 커다란 문제점은 크로스토크 현상이다. 크로스토크 현상을 제거하기 위하여 역필터를 설계하는 대표적인 방법 중 하나인 LNS 방법은 구현이 쉽고, 계산량이 적다는 장점이 있지만, 전달계의 변동이 발생하였을 경우에는 쉽게 대응할 수 없기 때문에 역필터의 성능이 저하되는 문제점을 갖고 있다.본 논문에서는 LNS방법을 이용하여 기 역필터를 설계하고, 그 역필터를 계속적으로 적응시켜 전달계가 변동하였을 때에도 변동된 전달계에 쉽게 대처할 수 있는 새로운 알고리즘을 제안하였다. 제안한 기법의 타당성을 입증하기 위하여 컴퓨터 시뮬레이션을 수행하여 기존의 방법과 비교한 결과, 크로스토크 제거 성능이 전 주파수 영역에서 개선됨을 확인하였다.

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원통형상에서의 표면복사 역해석에 관한 연구 (A Study on the Inverse Analysis of Surface Radiation in a Cylindrical Enclosure)

  • 김기완;백승욱;유홍선
    • 대한기계학회논문집B
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    • 제28권6호
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    • pp.705-712
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    • 2004
  • An inverse boundary analysis of surface radiation in an axisymmetric cylindrical enclosure has been conducted in this study. Net energy exchange method was used to calculate the radiative heat flux on each surface, and a hybrid genetic algorithm was adopted to minimize an objective function, which is expressed by sum of square errors between estimated and measured or desired heat fluxes on the design surface. We have examined the effects of the measurement error as well as the number of measurement points on the estimation accuracy. Furthermore, the effect of a variation in one boundary condition on the other boundary conditions was also investigated to get the same desired heat flux and temperature distribution on the design surface.

유한요소 역해석을 이용한 Tailor Welded Blank의 용접선 설계 (Design of Weld Line of a Tailor Welded Blank by Inverse Finite Element Analysis)

  • 이충호;허훈;한수식
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1997년도 추계학술대회논문집
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    • pp.89-92
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    • 1997
  • Design of a weld line in a tailor welded blank is indispensable for good manufacturing of stamped parts as assigned, since the intial weld line is distorted severely with forming. The initial weld line has to be determined such that desired weld line in a formed part can be obtained. The initial weld line was predicted by inverse finite element analysis from the desired weld line in a formed part. The inverse approach is applied to the cylindrical and square cup drawing with tailor welded blanks. The applications demonstrates that the approach is useful for design of weld line of tailor welded blank.

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박판금속성형의 초기 블랭크 최적설계를 위한 삼차원 다단계 역해석 (Three dimensional multi-step inverse analysis for optimum design of initial blank in sheet metal forming)

  • 이충호;허훈
    • 대한기계학회논문집A
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    • 제21권12호
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    • pp.2055-2067
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    • 1997
  • Values of process parameters in sheet metal forming can be estimated by various one-step inverse methods. One-step inverse methods based on deformation theory, however, cause some amount of error. The amount of error is generally increased as the deformation path becomes more complex. As a remedy, a new three dimensional multi-step inverse method is introduced for optimum design of blank shapes and strain distributions from desired final shapes. The approach extends a one-step inverse method to a multi-step inverse method in order to reduce the amount of error. The algorithm developed is applied to square cup drawing to confirm its validity by demonstrating reasonably accurate numerical results. Rapid calculation with this algorithm enables easy determination of an initial blank of sheet metal forming.

Triple Error Correcting Reed Solomon Decoder Design Using Galois Subfield Inverse Calculator And Table ROM

  • An Hyeong-Keon;Hong Young-Jin
    • 한국통신학회논문지
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    • 제31권1C호
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    • pp.8-13
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    • 2006
  • A new RS(Reed Solomon) Decoder design method, using Galois Subfield GF($2^4$) Multiplier, is described. The Decoder is designed using Normalized error position stored ROM. Here New Inverse Calculator in GF($2^8$) is designed, which is simpler and faster than the classical GF($2^8$) direct inverse calculator, using the Galois Subfield GF($2^4$) Arithmatic operator.

Performance Tuning Method of Inverse Optimal PID Control for Mechanical Systems

  • Choi, Young-Jin;Chung, Wan-Kyun;Youm, Young-Il
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.62.1-62
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    • 2001
  • This paper suggests an inverse optimal PID control design method for the trajectory tracking case of mechanical systems. Also, simple coarse/fine performance tuning laws are suggested based on the analysis for performance limitation of inverse optimal PID controller. Experimental results for a robot manipulator show the validity of our analysis for the performance tuning methods.

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Controller Design for a Piezoelectric Actuator Based on the Inverse Hysteresis Model

  • Ahn, Hyun-Sik;Park, Seung-Man
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2002년도 ICCAS
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    • pp.60.6-60
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    • 2002
  • $\textbullet$ Introduction $\textbullet$ Modeling of a Piezoelectric Actuator $\textbullet$ Inverse Hysteresis Modeling and Linearization $\textbullet$ Controller Design: PID plus Repetitive Controller $\textbullet$ Simulation Results $\textbullet$ Conclusion

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근사 역모델에 의한 이산시간 학습제어기의 수렴성 개선에 관한 연구 (A Study on the Improvement of Convergence for a Discrete-time Learning Controller by Approximated Inverse Model)

  • 문명수;양해원
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1989년도 하계종합학술대회 논문집
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    • pp.101-105
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    • 1989
  • The iterative learning controller makes the system output follow the desired output over a finite time interval through iterating trials. In this paper, first we discuss that the design problem of learning controller is originally the design problem of the inverse model. Then we show that the tracking error which is the difference between the desired output and the system output is reduced monotonically by properly modeled inverse system if the magnitude of the learning operator being introduced is bounded within the unit circle in complex domain. Also it would be shown that the conventional learning control method is a kind of extremely simplified inverse model learning control method of the objective controlled system. Hence this control method can be considered as a generalization of the conventional learning control method. The more a designer model the objective controlled system precisely, the better the performance of the approximated inverse model learning controller would be. Finally we compare the performance of the conventional learning control method with that of the approximated inverse model learning control method by computer simulation.

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