Uncorrelated center of pressure sway of human body

• Autorzy: Bosek M. , Grzegorzewski B.
• Języki publikacji: EN

Abstrakty

EN

Analysis of the human center of pressure (COP) trajectory allows quantification of the state of the postural controI system. In our consideration, as a model of COP sway, Langevin equation has been accepted. Using an analysis based on this equation, the friction coefficient and diffusion matrix have been obtained. The diffusion matrix is analysed using its trace, the angle, of rotation of the coordinate system making this matrix diagonal and the ratio nu of greater eigenvalue of this matrix to its trace. In the rotated coordinate system, with respect to the system defined by anteriorposterior and mediolateral directions, COP displacements, for time intervals shorter than 1 s, are uncorrelated. Eigenvalues of the diffusion matrix are diffusion coefficients in this coordinate system. For different populations, dependences between angle [...] and ratio nu have been found. The values of the diffusion coefficients in both directions of the rotated coordinate system were found to be closer one another, with the greater range of the variability of the angle of this rotation.

Słowa kluczowe

EN

posturography; posturaI control system; diffusion coefficient; Langevin equation

PL

posturografia; systemy sterowania; współczynniki dyfuzji; równanie Langevina

• Wydawca: Nałęcz Institute of Biocybernetics and Biomedical Engineering of the Polish Academy of Sciences ; Elsevier
• Czasopismo: Biocybernetics and Biomedical Engineering
• Rocznik: 2006
• Tom: Vol. 26, no. 4
• Strony: 33--38
• Opis fizyczny: Bibliogr. 19 poz., wykr.

Twórcy

autor

Bosek M.

autor

Grzegorzewski B.

• Departament of Biophysics, The Nicolaus Copernicus University in Toruń, The Ludwik Rydygier Collegium Medicum in Bydgoszcz, ul. Jagiellońska 13, 85-067 Bydgoszcz, Poland,

Bibliografia

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