Results 241 to 250 of about 24,705,416 (306)

Modelling for Scanning Impedance Imaging

2005 IEEE Engineering in Medicine and Biology 27th Annual Conference, 2005
Scanning electrical impedance imaging (SII) is a previously-introduced high resolution imaging modality with the potential of imaging the electrical activities of biological tissues. In this paper, a detailed complex electrostatic model is derived to describe the physical phenomena of the SII system.
Hongze, Liu, Aaron, Hawkins, Stephen, Schultz, Travis, Oliphant   +3 more
openaire   +2 more sources

Outdoor ground impedance models

The Journal of the Acoustical Society of America, 2011
Many models for the acoustical properties of rigid-porous media require knowledge of parameter values that are not available for outdoor ground surfaces. The relationship used between tortuosity and porosity for stacked spheres results in five characteristic impedance models that require not more than two adjustable parameters.
Keith, Attenborough, Imran, Bashir, Shahram, Taherzadeh   +2 more
openaire   +2 more sources

Surface impedance models for high impedance surfaces

Applied Physics A, 2011
Different analytical and numerical methods for calculating the surface impedance of a high impedance surface (HIS) structure have been studied and compared. In this article, two new approaches are proposed for calculating the surface impedance for general 2D-spatial periodic HIS structures, which include both the symmetric and asymmetric planar ...
Zhu, Y., Bossavit, A., Zouhdi, Said
openaire   +2 more sources

Frequency-Coupling Impedance Model Based Analysis of a High-Frequency Resonance Incident in an Actual MMC-HVDC System

IEEE Transactions on Power Delivery, 2020
Recently, a high-frequency resonance (HFR) incident has been captured in an actual HVDC project of China Southern Power Grid, which is regarded as a new stability issue caused by the interaction between the modular multilevel converter (MMC) and the weak
J. Man, Xiaorong Xie, Shukai Xu, Changyue Zou, C. Yin   +4 more
semanticscholar   +1 more source

Modeling of Subdiffusion Impedance in Multilayer Nanostructures

2021 11th International Conference on Advanced Computer Information Technologies (ACIT), 2021
Mathematical model of the subdiffusion impedance in multilayer nanostructures is considered on the basis of the Cattaneo-type diffusion equation in fractional derivatives. The Nyquist diagrams are calculated for different values of subdiffusion coefficient and time parameter (time for which the flow delays concerning the gradient of charge carriers ...
Petro Kostrobij, Ivan Grygorchak, Bogdan Markovych, Iryna Ryzha, Oleksandra Viznovych, Mykhailo Tokarchuk   +5 more
openaire   +1 more source

Comparison of Impedance Model and Amplitude–Phase Model for Power- Electronics-Based Power System

IEEE Journal of Emerging and Selected Topics in Power Electronics, 2020
Recently power electronics devices have been widely used in power systems, and the dynamical behavior of the power system has been changing with their increasing penetration.
Ziqian Yang, Cong Mei, Shijie Cheng, M. Zhan   +3 more
semanticscholar   +1 more source

The LEP impedance model

Proceedings of International Conference on Particle Accelerators, 2002
The bunch current in LEP is limited by collective effects slightly below its design value. To understand this limitation, a set of experiments has been carried out to obtain a model of the impedance seen by the circulating beam. From measurements of the current dependance of the synchrotron and betatron frequencies information about the longitudinal ...
D. Brandt, K. Cornelis, V. Danilov, A. Hofmann, C. Juillard, E. Perevedentsev, E. Peschardt, E. Rossa, F. Tecker, D. Wang, B. Zotter, L. Rivkin   +11 more
openaire   +1 more source

Extracting Optimized Bio-Impedance Model Parameters Using Different Topologies of Oscillators

IEEE Sensors Journal, 2020
This paper demonstrates the possibility of extracting the single-dispersion and double-dispersion Cole-bio-impedance model parameters using oscillators (sinusoidal or relaxation).
Menna Mohsen, L. Said, A. Elwakil, A. Madian, A. G. Radwan   +4 more
semanticscholar   +1 more source

An impedance model to improve the higher frequency limit of electrical measurements on the capacitor cell made from electrodes of finite resistances

Social Science Research Network
capacitors are highly affected above 100 kHz due to the presence of the electrodes resistance and leads inductance. An impedance model has been used to improve the higher frequency limit of the dielectric measurements on the isotropic liquids and ...
R. Dhar
semanticscholar   +1 more source

Analysis and diagnosis of PEM fuel cell failure modes (flooding & drying) across the physical parameters of electrochemical impedance model: Using neural networks method

Sustainable Energy Technologies and Assessments, 2019
The objective of this work is to define and implement a method of artificial neural network to create an optimal impedance model of the proton exchange membrane fuel cell (PEMFC) which considers the electrochemistry and the mass transfer theory, which ...
S. Laribi, Khaled Mammar, Y. Sahli, Khaled Koussa   +3 more
semanticscholar   +1 more source