대한의용생체공학회:의공학회지 (Journal of Biomedical Engineering Research)

  • 제29권3호
  • /
  • Pages.231-238
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  • 2008
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  • 1229-0807(pISSN)
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  • 2288-9396(eISSN)
대한의용생체공학회 (The Korean Society of Medical and Biological Engineering)
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개선된 다운힐 심플렉스 법을 이용한 주파수 영역에서의 뇌자도 신호원 추정

Magnetoencephalography Source Localization using Improved Downhill Simplex Method in Frequency Domain

  • Kim, Byeong-Jun (School of Electrical Engineering, Seoul National University) ;
  • An, Kwang-Ok (School of Electrical Engineering, Seoul National University) ;
  • Lee, Chany (School of Electrical Engineering, Seoul National University) ;
  • Jung, Hyun-Kyo (School of Electrical Engineering, Seoul National University)
  • 발행 : 2008.06.30
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초록

Nelder-Mead downhill simplex method (DSM), a kind of deterministic optimization algorithms, has been used extensively for magnetoencephalography(MEG) dipolar source localization problems because it dose not require any functional differentiation. Like many other deterministic algorithms, however, it is very sensitive to the choice of initial positions and it can be easily trapped in local optima when being applied to complex inverse problems with multiple simultaneous sources. In this paper, some modifications have been made to make up for DSM's limitations and improve the accuracy of DSM. First of all, initial point determination method for DSM using magnetic fields on the sensor surface was proposed. Secondly, Univariant-DSM combined DSM with univariant method was proposed. To verify the performance of the proposed method, it was applied to simulated MEG data and practical MEG measurements.

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참고문헌

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