Izvestiya of Saratov University.
ISSN 1817-3020 (Print)
ISSN 2542-193X (Online)


Assessment of spatiotemporal heterogeneity of two-dimensional images on the example of photoplethysmograpic imaging of hemodynamics

Background and Objectives: The problem of representation of multidimensional data on a two-dimensional plane arises during the processing of a series of two-dimensional images in the spatiotemporal and time-frequency domains. When implementing time-frequency analysis, each point of the object is characterized by a function of two arguments, therefore, to visualize the results on a two-dimensional plane, it is necessary to reduce the data dimension.

Complex Waveforms and Synchronization in Functional Model of Vascular Nephron Tree

We suggest functional model that qualitatively describes oscillatory processes in renal autoregulation. Our model consists of ensemble of two-mode oscillators that are coupled by means of two different pathways. The above coupling pathways count both the geometry of ensemble (tree-like structure or local interaction) and the specific action of individual oscillator (energy distribution netrwork or diffusive coupling). We study the typical operating regimes of suggested model as well as transitions between them.