• Title/Summary/Keyword: SIR criteria

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Evaluation of Arousal Level to Prevent Drowsy Driving by Fuzzy Inference (졸음운전 방지를 위한 fuzzy 추론에 의한 각성도의 평가)

  • Kim, Y. H.;Ko, H. W.;Lyou, J.
    • Journal of Biomedical Engineering Research
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    • v.18 no.4
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    • pp.491-498
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    • 1997
  • This paper describes the arousal measurement and control system using fuzzy logic to prevent drowsy driving. Sugeno's method was used for fuzzy inference in this study. Arousal evaluation and control criteria were modified from result of Nz-IRI analysis depending on arousal sate. Membership function and rule base of fuzzy inference were determined from the modified arousal level criteria When lRl (Inter-SIR Interval) was shorter than 60sec, outputs of both methods were changed from small to big, but output of three step warning method was same level until the next warning range. Since output of fuzzy inference tracked well the change of subject's arousal level, problems of three step warning method could be overcome by fuzzy inference method Furthermore, the output of the fuzzy inference was highly correlated with Nz(r = 0.99). Therefore, the fuzzy inference method for evaluation and the control of arousal will be more effective at real driving situation than three step warning method.

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Recent updates for biomaterials used in total hip arthroplasty

  • Hu, Chang Yong;Yoon, Taek-Rim
    • Biomaterials Research
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    • v.22 no.4
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    • pp.259-270
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    • 2018
  • Background: Total hip arthroplasty (THA) is probably one of the most successful surgical interventions performed in medicine. Through the revolution of hip arthroplasty by principles of low friction arthroplasty was introduced by Sir John Charnley in 1960s. Thereafter, new bearing materials, fixation methods, and new designs has been improved. The main concern regarding failure of THA has been the biological response to particulate polyethylene debris generated by conventional metal on polyethylene bearing surfaces leading to osteolysis and aseptic loosening of the prosthesis. To resolve these problems, the materials of the modern THA were developed since then. Methods: A literature search strategy was conducted using various search terms in PUBMED. The highest quality articles that met the inclusion criteria and best answered the topics of focus of this review were selected. Key search terms included 'total hip arthroplasty', 'biomaterials', 'stainless steel', 'cobalt-chromium', 'titanium', 'polyethylene', and 'ceramic'. Results: The initial search retrieved 6921 articles. Thirty-two articles were selected and used in the review. Conclusion: This article introduces biomaterials used in THA and discusses various bearing materials in currentclinical use in THA as well as the newer biomaterials which may even further decrease wear and improve THA survivorship.