Riparian buffers are a proven practice for removing NO from overland flow and shallow groundwater. However, in landscapes with artificial subsurface (tile) drainage, most of the subsurface flow leaving fields is passed through the buffers in drainage pipes, leaving little opportunity for NO removal. We investigated the feasibility of re-routing a fraction of field tile drainage as subsurface fl...

It is shown that an equilateral convex pentagon tiles the plane if and only if it has two angles adding to 180 o or it is the unique equilateral convex pentagon with Although the area of mathematical tilings has been of interest for a long time there is still much to be discovered. We do not even know which convex polygons tile the plane. Furthermore, for those polygons which do tile, new tilin...

Tile logic extends rewriting logic, taking into account rewriting with side-eeects and rewriting synchronization. Since rewriting logic is the semantic basis of several language implementation eeorts, it is interesting to map tile logic back into rewriting logic in a conservative way, to obtain executable speciications of tile systems. The resulting implementation requires a meta-layer to contr...

Majumder, Reif and Sahu have presented a stochastic model of reversible, error-permitting, two-dimensional tile self-assembly, and showed that restricted classes of tile assembly systems achieved equilibrium in (expected) polynomial time. One open question they asked was how much computational power would be added if the model permitted multiple nucleation, i.e., independent groups of tiles gro...

In this paper we show that passive self-assembly in the context of the tile self-assembly model is capable of performing fuel efficient, universal computation. The tile self-assembly model is a premiere model of self-assembly in which particles are modeled by four-sided squares with glue types assigned to each tile edge. The assembly process is driven by positive and negative force interactions...

By PAUL HELLER, JOHN VAN STONE, DAVID APPLE AND RICHARD D. COLEMAN A RARE FORM of hereditary anemia characterized by hypochromia of the erythrocytes in tile presence of increased iron stores has been designated by Heilmeyer1’2 as “hereditary hypochromic sideroachrestic anemia.” Garby and his co-workers3 and Hei1meyer1’ ’ have suggested that in this disorder heme synthesis is disturbed possibly ...

We study the minimal complexity of tilings of a plane with a given tile set. We note that any tile set admits either no tiling or some tiling with O(n) Kolmogorov complexity of its (n× n)squares. We construct tile sets for which this bound is tight: all (n × n)-squares in all tilings have complexity Ω(n). This adds a quantitative angle to classical results on non-recursivity of tilings – that w...

In this paper, we study a class of polycubes that tile the space by translation in a non lattice periodic way. More precisely, we construct a family of tiles indexed by integers with the property that Tk is a tile having k ≥ 2 has anisohedral number. That is k copies of Tk are assembled by translation in order to form a metatile. We prove that this metatile is lattice periodic while Tk is not a...

ABSfRACf The Pitman closeness criterion is an intrinsic measure of the comparative behavior of two estimators. based solely on their joint distribution. It generally entails less stringent regulari ty condi tions than in other measures. But. there are some undesirable features of this measure. The past few years have witnessed some developments on Pitman-closeness in its tributaries. and a crit...

We prove that for every nite tile set, isometric copies of which can tile euclidean n-space, there is a tiling with the local iso-morphism property.