The computer-assisted investigation of flow data can be eased by the visualization of topological information about the flow. Especially, when empirical models or numerical results from flow simulation are investigated, often the first step of analysis is to search structural elements, like fixed points, separatrices, etc. The work presented in this paper focuses on the visualization of 3D dyna...

This paper reviews various impacts of urbanization on rivers and streams, which lead to symptoms summarized by the general term “urban stream syndrome”. Growing areas of impervious surfaces cause deterioration of water recipients flowing through urban areas. The symptoms of deterioration usually include altered chemical parameters of water and sediment, accumulation of priority pollutants in aq...

The fine and applied visual arts and perceptual psychology use conflicting accounts of picture perception. In the arts, the human ability to perceive pictured objects is characterized as learned, or conventionalized, like a ”visual language” (Gombrich, 1960; Goodman, 1976; Kulvicki, 2010). In perceptual psychology, picture perception is characterized as an unlearned, biologically grounded, abil...

Hydromagnetic effects are analyzed on flow and heat transfer over a horizontal surface placed in an externally squeezed free stream. The unsteady governing momentum and energy equations are transformed to similarity equations for certain families of the controlling parameters. It is found that both local wall shear stress and local Nusselt number increase as squeezing free stream velocity incre...

A new technique for microscopic imaging of electrochemically active surfaces is introduced. The technique combines concepts of probe microscopy and advances in mass spectrometry. The technique is based on a miniature electrochemical flow cell scanner. A liquid feed stream containing a redox component is introduced to the vicinity of the examined location through the annulus of a coaxial capilla...

Many theories of visual object perception assume the visual system initially extracts borders between objects and their background and then "fills in" color to the resulting object surfaces. We investigated the transformation of chromatic signals across the human ventral visual stream, with particular interest in distinguishing representations of object surface color from representations of chr...

The investigation of flow data can be eased by the visualization of topological information about the flow. Especially, when empirical models or numerical results from flow simulation are investigated, often the first step of analysis is to search structural elements, like fixed points, separatrices, etc. The work presented in this paper focuses on the visualization of 3D dynamical systems (com...

The relationship between pH and the abundance and activity of bacteria in streams was examined as part of a study of the effect of acidification on stream communities. Of the bacterial communities examined, the epilithic community appeared to be the most significantly affected by acidification. Microbial biomass, as quantified by measuring the ATP level, on rock surfaces was significantly corre...

The change in the impervious-pervious balance has significantly altered the stream water quality, and thus the threshold of the impervious surface area in the watershed has been an active research topic for many years. The objective of this study is to verify the correlation between impervious surfaces and water quality and to determine the threshold of the percentage of the impervious surface ...

It is shown that nonlinear interactions between boundary layers on adjacent corner surfaces produce deterministic stream wise spiral structures. The synchronization properties of nonlinear spectral velocity equations of Lorenz form yield clearly defined deterministic spiral structures at several downstream stations. The computational procedure includes Burg’s method to obtain power spectral den...