A5027409359- Advanced Control Systems Design
- Electrical and Bioimpedance Tomography
- Body Composition Measurement Techniques
- Analog and Mixed-Signal Circuit Design
- Microfluidic and Bio-sensing Technologies
- Muscle activation and electromyography studies
- Advancements in PLL and VCO Technologies
- Advanced Battery Technologies Research
- Hemodynamic Monitoring and Therapy
- Sensor Technology and Measurement Systems
- Control Systems and Identification
- Sports Performance and Training
- Electric and Hybrid Vehicle Technologies
- Non-Invasive Vital Sign Monitoring
- Experimental Learning in Engineering
- Extremum Seeking Control Systems
- Supercapacitor Materials and Fabrication
- Digital Filter Design and Implementation
- Acoustic Wave Resonator Technologies
- Engineering Education and Curriculum Development
- Vibration Control and Rheological Fluids
- Engineering and Technology Innovations
- Biomedical and Engineering Education
- Fractional Differential Equations Solutions
- Advanced Sensor and Energy Harvesting Materials
University of Alabama
2016-2025
University of North Carolina at Chapel Hill
2024
University of Calgary
2010-2014
In this survey, we present many of the fractional- order circuit models used in biomedicine and biology to fit experimentally collected impedance data. An overview different methods extract parameters from datasets are also presented. Applications fractional for modelling human tissue, plant physiology, respiratory systems, tissue-electrode interfaces presented highlight significance these their potential further research. This survey is a tutorial nature intended as an introduction...
Abstract The electric characteristics of electric-double layer capacitors (EDLCs) are determined by their capacitance which is usually measured in the time domain from constant-current charging/discharging and cyclic voltammetry tests, frequency using nonlinear least-squares fitting spectral impedance. time-voltage current-voltage profiles first two techniques commonly treated assuming ideal S s C behavior spite response device, turn provides inaccurate values for its characteristic metrics....
This paper surveys fractional-order electric circuit models that have been reported in the literature to best fit experimentally collected impedance data from energy storage and generation elements, including super-capacitors, batteries, fuel cells. In all surveyed models, employment of capacitors, also known as constant phase is imperative not only accuracy model but reflect physical electrochemical properties device.
In this paper, we propose using a numerically solved least squares fitting process to estimate the impedance parameters of fractional order model supercapacitors from their voltage excited step response, without requiring direct measurement or frequency response. Experimentally estimated low capacity 0.33, 1, and 1.5 F in time range 0.2-30 s high 1500 3000 0.2-90 verify proposed domain method showing less than 3% relative error between simulated response (using extracted parameters)...
In this study, the authors propose use of field programmable analogue array hardware to implement an approximated fractional step transfer function order (n+α) where n is integer and 0 < α 1. The show how these filters can be designed using approximation Laplacian operator sα. First fourth-order low- high-pass with steps from 0.1 0.9, that 1.1–1.9 4.1–4.9, respectively, are given as examples. MATLAB simulations experimental results verify implementation operation filters.
We propose the use of nonlinear least squares optimization to approximate passband ripple characteristics traditional Chebyshev lowpass filters with fractional order steps in stopband. MATLAB simulations of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mrow><mml:mi>(1+α)</mml:mi></mml:mrow></mml:math>,<mml:math id="M2"><mml:mrow><mml:mi>(2+α)</mml:mi></mml:mrow></mml:math>, and<mml:math id="M3"><mml:mrow><mml:mi>(3+α)</mml:mi></mml:mrow></mml:math>order from<mml:math...
Abstract The porous nature of the electrode material in supercapacitors and apparent conductivity electrolyte cause their impedance to show a complex frequency‐dependent behavior, which turn makes it incorrect treat them as ideal capacitors, even at frequency few millihertz. This is particularly crucial if intended application requires configuration that uses stacked supercapacitor banks, errors defining metrics individual components accumulate. Although manufacturers provide ratings under...
In this paper we propose the use of fractional capacitors in Tow-Thomas biquad to realize both lowpass and asymmetric bandpass filters order 0<α1+α2≤2, where α1 α2 are orders 0<α1,2≤1. We show how these can be designed using an integer-order transfer function approximation capacitors. MATLAB PSPICE simulations first fractional-step low 1.1, 1.5, 1.9 given as examples. Experimental results pass 1.5 implemented with silicon-fabricated verify operation biquad.
We propose the use of a fractional order capacitor and inductor with orders<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M2"><mml:mn mathvariant="normal">0</mml:mn><mml:mo>≤</mml:mo><mml:mi>α</mml:mi></mml:math>, <mml:math id="M3"><mml:mi>β</mml:mi><mml:mo>≤</mml:mo><mml:mn mathvariant="normal">1</mml:mn></mml:math>, respectively, in fractional<mml:math...
Two (α + β)-order transfer functions realizing fractional-order band-pass filter responses are presented and analysed, where 0 < α ≤ 1 β 1. Generalizing the from integer to fractional order offers continuous independent control of magnitude characteristic slopes both below above center frequency. The function coefficients that minimize error between discussed proposed fractional-characteristic specimen in a specified frequency band determined using numerical least squares optimization search...
Electrical impedance measurements of biological tissues, also referred to as bioimpedance, quantify the passive electrical properties these materials. The motivation behind collecting is provide details regarding electrochemical structures and processes within tissues. Bioimpedance measures have recently been investigated a method monitor morphological physiological changes that occur in skeletal muscle during contraction well result from fatigue. Objective: To investigate effect exercise...