We show that every n-point tree metric admits a (1 + ε)-embedding into ` C(ε) logn 1 , for every ε > 0, where C(ε) ≤ O ( ( 1ε ) 4 log 1ε ) ) . This matches the natural volume lower bound up to a factor depending only on ε. Previously, it was unknown whether even complete binary trees on n nodes could be embedded in ` O(logn) 1 with O(1) distortion. For complete d-ary trees, our construction ach...

Pruning plays an integral role in reducing the search space of nearest neighbor queries on data structures like the R-tree. We show that a popular pruning strategy for nearest queries can reduce the search space exponentially in R-trees. In light of this, we provide a generalization of the strategy to k-nearest neighbors. We call the extension Promise-Pruning and, for any k, construct a class o...

Forest management alters species behaviours, distributions and interactions. To evaluate forestry effects on ant foraging performance, we compared the quality and quantity of honeydew harvested by ants among clear-cuts, middle-aged and mature spruce-dominated stands in boreal forests in Sweden. Honeydew quality was examined using honeydew collected by squeezing the gasters of laden Formica aqui...

Mobile laser scanning acquires massive point clouds in urban areas to provide high resolution data for 3D city modelling. A workflow for detecting and modelling trees from point clouds is presented. Emphasis lies on data reduction using an alpha shape approach. From the reduced point cloud the parameters are extracted to model the 3D trees using the Weber and Penn (1995) approach. The workflow ...

Evaluation of Coastal Plain Conservation Buffers using the Riparian Ecosystem Management Model (In Press, Journal of the American Water Resources Association) Richard Lowrance*, Randall G. Williams, Shreeram P. Inamdar, David D. Bosch, and Joseph M. Sheridan. ABSTRACT Riparian buffers are increasingly important as watershed management tools and are cost-shared by programs such as Conservation R...

A study to mea~ure the effect of walnut scale infestation on English walnut qualityand yield has shown no differences in yield and no consistentdifferencein kernel quality between infested and non-infested trees for the four years ~f the study. Yield and quality of English walnut are not overly sensitive to walnut scale infestation and some degree of infestation can be tolerated with no measura...