• 제목/요약/키워드: brain engineering

검색결과 1,375건 처리시간 0.037초

Noninvasive Brain Stimulation Using a Modulated Microwave Signal

  • Seo, Taeyoon;Oh, Seongwoog;Jung, Dahee;Huh, Yeowool;Cho, Jeiwon;Kwon, Youngwoo
    • Journal of electromagnetic engineering and science
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    • 제18권1호
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    • pp.70-72
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    • 2018
  • We propose a microwave signal generation system for brain stimulation. The existing brain stimulation system uses a signal of several tens of kHz, and the magnetic field distribution is wide. Microwave is used to locally limit the distribution of the electromagnetic field and to change the action potential of the cell with less power. The switch modulates the microwave signal to obtain a pulse envelope. The action potential of the cell can be controlled to the excitation/inhibition state by adjusting the repetition frequency. These results are confirmed by measuring the cell potential of the mouse brain.

성인 뇌와 유아 뇌 모델의 진동 특성 해석 (Analysis of the Vibratory Characteristic of the Adult's and Baby's Brain Model)

  • 김영은;유진환
    • 대한의용생체공학회:의공학회지
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    • 제19권6호
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    • pp.611-616
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    • 1998
  • 머리(뇌 포함) 부분에 대한 3차원 유한 요소 모델을 이용하여 진동 방향에 따른 응답특성을 해석하였다. 해석 결과 성인의 뇌는 9Hz, 14Hz에서 고유 진동수를 나타내었으며 유아의 뇌에서는 2Hz, 3Hz에서 고유 진동수가 계산되었다. 진동 방향에 관계없이 각 진동에 대해 계산된 가속도를 제외한 전단력, 압력, von-Mises 값의 최대, 최소값의 비는 성인에 비해 유아모델에서 더 크게 나타났다. 각 고유 진동수에서 성인모델은 14Hz에서 상지 중추보다 하지 중추를 관장하는 뇌의 영역에서 보다 큰 응력이 계산되어 상지에 의한 오동작 보다 하지에 의한 오동작을 일으킬 가능성이 더 큼을 유추할 수 있었다.

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정상 노화군과 경도인지장애 환자군의 18F-FDG-PET과 11C-PIB-PET 영상을 이용한 뇌 연결망 분석 (Brain Connectivity Analysis using 18F-FDG-PET and 11C-PIB-PET Images of Normal Aging and Mild Cognitive Impairment Participants)

  • 손성진;박현진
    • 대한의용생체공학회:의공학회지
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    • 제35권3호
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    • pp.68-74
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    • 2014
  • Recent research on mild cognitive impairment (MCI) has shown that cognitive and memory decline in this disease is accompanied by disruptive changes in the brain functional network. However, there have been no graph-theoretical studies using $^{11}C$-PIB PET data of the Alzheimer's Disease or mild cognitive impairment. In this study, we acquired $^{18}F$-FDG PET and $^{11}C$-PIB PET images of twenty-four normal aging control participants and thirty individuals with MCI from ADNI (Alzheimer's Disease Neuroimaging Initiative) database. Brain networks were constructed by thresholding binary correlation matrices using graph theoretical approaches. Both normal control and MCI group showed small-world property in $^{11}C$-PIB PET images as well as $^{18}F$-FDG PET images. $^{11}C$-PIB PET images showed significant difference between NC (normal control) and MCI over large range of sparsity values. This result will enable us to further analyze the brain using established graph-theoretical approaches for $^{11}C$-PIB PET images.

Accuracy of image registration for radiation treatment planning using a brain phantom

  • Jin, Ho-Sang;Suh, Tae-Suk;Song, Ju-Young;Juh, Ra-Hyeong;Kwark, Chul-Eun;Lee, Hyoung-Koo;Choe, Bo-Young
    • 대한자기공명의과학회:학술대회논문집
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    • 대한자기공명의과학회 2002년도 제7차 학술대회 초록집
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    • pp.106-106
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    • 2002
  • Purpose: The purposes of our study are (1) to develop a brain phantom which can be used for multimodal image registration, (2) to evaluate the accuracy of image registration with the home-made phantom. Method: A brain phantom which could be used for image registration technique of CT-MR and CT-SPECT images using chamfer matching was developed. The brain phantom was specially designed to obtain imaging dataset of CT, MR, and SPECT. The phantom had an external frame with 4 N-shaped pipes filled with acryl rods for CT, MR imaging and Pb rods for SPECT imaging. 8 acrylic pipes were inserted into the empty space of the brain phantom to be imaged for geometric evaluation of the matching. Accuracy of image fusion was assessed by the comparison between the center points of the section of N-shaped bars in the external frame and the inserted pipes of the phantom. Technique with partially transparent, mixed images using color on gray was used for visual assessment of the image registration process.

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Time-multiplexing과 바이오 피드백을 이용한 EEG기반 뇌-컴퓨터 인터페이스 시스템 (EEG Based Brain-Computer Interface System Using Time-multiplexing and Bio-Feedback)

  • 배일한;반상우;이민호
    • 센서학회지
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    • 제13권3호
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    • pp.236-243
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    • 2004
  • In this paper, we proposed a brain-computer interface system using EEG signals. It can generate 4 direction command signal from EEG signals captured during imagination of subjects. Bandpass filter used for preprocessing to detect the brain signal, and the power spectrum at a specific frequency domain of the EEG signals for concentration status and non-concentration one is used for feature. In order to generate an adequate signal for controlling the 4 direction movement, we propose a new interface system implemented by using a support vector machine and a time-multiplexing method. Moreover, bio-feed back process and on-line adaptive pattern recognition mechanism are also considered in the proposed system. Computer experimental results show that the proposed method is effective to recognize the non-stational brain wave signal.

A Study on the Future Storage System as brain coordinator

  • Yi, Cheon-Hee;Yi, Jae-Young
    • 반도체디스플레이기술학회지
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    • 제8권1호
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    • pp.39-42
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    • 2009
  • In this paper an attempt for realizing a storage system which works as a part of human brain has been discussed. The system is expected to be able to coordinate with human brain. And current storage may have inherent problem due to an intrinsic attribute of storage, exclusiveness. Directory structure in it must be a source of confusion, if it used out side of the range of limitation. Adapting multidimensional annotation of file name extension and directory-less file system, a new storage system able to associate and coordinate with human brain may be available near future. This paper showed that the limitation of current storage system clearly exists, because of human brain limitation to memorize directory name.

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