in this paper, effects of the cross shore and groyne wall slopes on flow parameters around an impermeable groyne were considered using a three-dimensional numerical cfd model (i.e., fluent). the k-ε turbulence model was used to evaluate the reynolds stresses. the model was first applied to a vertical groyne on a flat bed and the model results were compared with the relevant experimental data. t...

A natural and practical criterion in the preparation of diagrams of ordered sets is to minimize the number of different slopes used for the edges. Any diagram requires at least the maximum number of upper covers (or of lower covers) of any element. While this maximum degree is not always enough we show that it is as long as any edge joining a covering pair may be bent, to produce a crooked diag...

For the figure eight knot, we show that slopes with even numerator are slopes of immersed surfaces covered by incompressible, boundary-incompressible embeddings in some finite cover.  2000 Elsevier Science B.V. All rights reserved.

We study straight-line drawings of graphs with few segments and few slopes. Optimal results are obtained for all trees. Tight bounds are obtained for outerplanar graphs, 2-trees, and planar 3-trees. We prove that every 3-connected plane graph on n vertices has a plane drawing with at most 5n/2 segments and at most 2n slopes, and that every cubic 3-connected plane graph has a plane drawing with ...

Three behavioural tasks (standard visual search, multiple target search, and numberdiscrimination)weretestedwithavariety of stimuli relevanttotwo-stage theories of vision. One purpose was to compare the two versions of the search task; a second was to explore the relations between processes of search and enumeration. The two search tasks were quite consistent overall, with strong correlations b...