title: Analysis of chaotic and noise processes in a fluctuating blood flow using the Allan variance technique.
abstract: OBJECTIVE
  The aim of this work was to develop a novel technique for digital processing of Doppler ultrasound blood flow sensor data from noisy blood flow velocity waveforms.
  
  
  METHODS
  To evaluate the fluctuating blood flow parameters, various nonlinear dynamics methods and algorithms are often being used. Here, for identification of chaotic and noise components in a fluctuating coronary blood flow, for the first time the Allan variance technique was used. Analysis of different types of noises (White, Brownian, Flicker) was carried out and their strong correlation with fractality of time series (the Hurst exponent) was revealed.
  
  
  RESULTS
  Based on a specialized software realizing the developed technique, numerical experiments with real clinical data were carried out. Recommendations for identification of noisy patterns of coronary blood flow in normal and pathological states were developed.
  
  
  CONCLUSIONS
  The methodology gives us the possibility for the more detailed quantitative and qualitative analysis of a noisy fluctuating blood flow data.
authors: Theoretical Informatics and Computer Technologies, Bauman Moscow State Technical University, Moscow, Russia.
authors: M A
authors: MA
authors: Basarab
authors: Department of Cardiovascular Surgery, St.Ioasaf's Belgorod Regional Hospital, Belgorod, Russia.
authors: D A
authors: DA
authors: Basarab
authors: Sector of Fundamental Problems of Control and Information Systems, Bauman Moscow State Technical University, Moscow, Russia.
authors: N S
authors: NS
authors: Konnova
authors: Research Institute on General Pathology and Pathophysiology, Moscow, Russia.
authors: D D
authors: DD
authors: Matsievskiy
authors: Department of Informatics and Control Systems, Bauman Moscow State Technical University, Moscow, Russia.
authors: V A
authors: VA
authors: Matveev
mesh_terms: D001783:Blood Flow Velocity / Q000235:genetics*; D006801:Humans; D009622:Noise; D017711:Nonlinear Dynamics
keywords: Alavar; Allan variance; Blood flow; Doppler flowmetry; Hurst exponent; nonlinear dynamics