forest fragmentation results in a loss of forest interior and an increase in edge habitat. we studied how understorey bird community composition and habitat variables changed along an edge-to-interior gradient in a 1248-ha lowland rainforest patch in peninsular malaysia. birds and environmental variables such as vegetation structure and litter depth were detected within a 25-m radius of each of...

In this paper, we propose a fast circular edge detector for the iris region segmentation by detecting the inner and outer boundaries of the iris. In previous work, the circular edge detector which John G.Daugman proposed, searches the radius and the center of the iris to detect its outer boundary over an eye image. To do so, he used Gaussian filter to smooth texture patterns of the iris which c...

We consider the Tree Augmentation problem: given a graph G = (V,E) with edge-costs and a tree T on V disjoint to E, find a minimum-cost edge-subset F ⊆ E such that T ∪ F is 2-edge-connected. Tree Augmentation is equivalent to the problem of finding a minimumcost edge-cover F ⊆ E of a laminar set-family. The best known approximation ratio for Tree Augmentation is 2, even for trees of radius 2. A...

The corrosion resistance of magnesium alloys depends mainly on its surface integrity. Previous experimental studies have shown that machining can induces small (nano-scale) grain size, compressive residual stresses and basal plane crystallographic texture, which significantly improve the corrosion resistance of magnesium alloy. These studies have focused on the positive effects of cryogenic coo...

Let G = (V, E) be a graph with a non-negative edge length lu,v for every (u, v) ∈ E. The vertices of G represent locations at which transmission stations are positioned, and each edge of G represents a continuum of demand points to which we should transmit. A station located at v is associated with a set Rv of allowed transmission radii, where the cost of transmitting to radius r ∈ Rv is given ...

Applications in molecular biology more and more require geometric data management along with physicochemical data handling. Thus, 3D structures and surfaces of molecules become basic objects in molecular databases. We propose the neighborhood query on graphs such as molecular surfaces as a fundamental query class concerning topological information on patch adjacency. Furthermore, we suggest a p...

The filling radius function R of Gromov measures the minimal radii of van Kampen diagrams filling edge-circuits w in the Cayley 2complex of a finite presentation P. It is known that the Dehn function can be bounded above by a double exponential in R and the length of the loop, and it is an open question whether a single exponential bound suffices. We define the upper filling radius R(w) of w to...

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