In the computational theory of human vision, developed by D. Marr and his school, zero-crossings detection is proposed as one of the first stages of human visual information processing. The justif ication of this theory reguires that the zero crossings are rich in information about the original image. In a paper, T. Poggio, H.K. Nishihara and K.R.K. Nielsen stated that a successful extension of...

This paper investigates fatal accidents and fatalities at level crossings in Great Britain over the 64-year period 1946-2009. The numbers of fatal accidents and fatalities per year fell by about 65% in the first half of that period, but since then have remained more or less constant at about 11 fatal accidents and 12 fatalities per year. At the same time other types of railway fatalities have f...

Previous work used polygonal realizations of knots to reduce the problem computing superbridge number a realization linear programming problem, leading new sharp upper bounds on index knots. The present extends this technique with an odd edges and determines exact many knots, including majority 9-crossing for which it was previously unknown and, first time, several 12-crossing Interestingly, at...

A multigraph drawn in the plane is called non-homotopic if no pair of its edges connecting same vertices can be continuously transformed into each other without passing through a vertex, and loop shrunk to end-vertex way. Edges are allowed intersect themselves. It easy see that on n>1 have arbitrarily many edges. We prove number crossings between with n m>4n larger than cm2n for some constant c...

The water quality impact of a herd of 246 dairy cows crossing a stream ford was documented. Two cow crossings produced plumes of turbid water associated with very high concentrations of faecal indicator bacteria (Escherichia coli) and high suspended solids (SS) and total nitrogen (TN). On the first crossing, towards the milking shed, the cows were tightly-bunched and produced a sharp spike of c...