A method for partitioning shapes is described based on a global convexity measure. Its advantages are that its global nature makes it robust to noise, and apart from the number of partitioning cuts no parameters are required. In order to ensure that the method operates correctly on bent or undulating shapes a process is developed that identifies the underlying bending and removes it, straighten...

Partitionable skew Room frames of type hn have played an important role in the constructions of 4-frames, (K4 − e)-frames and super-simple (4, 2)-frames. In this paper, we investigate the existence of partitionable skew Room frames of type hn. The necessary conditions for the existence of such a design are that h(n − 1) ≡ 0 (mod 4) and h 5. It is proved that these necessary conditions are also ...

The design of a parallel implementation of multilevel recursive spectral bisection (PMRSB) is described. The code is fast enough to enable dynamic repartitioning of adaptive meshes and to partition meshes that are too large for workstations. Two innovations in the implementation are recursive asynchronous task teams and a parallel version of the multilevel accelerator. A performance improvement...

Lewis sender-receiver games illustrate how a meaningful term language might evolve from initially meaningless random signals (Lewis 1969; Skyrms 2006). Here we consider how a meaningful language with a primitive grammar might evolve in a somewhat more subtle sort of game. The evolution of such a language involves the co-evolution of partitions of the physical world into what may seem, at least ...

A method for determining consensus of hierarchical incomplete ordered partitions and coverings of sets is presented in this chapter. Incomplete ordered partitions and coverings are often used in expert information analysis. These structures should be useful when an expert has to classify elements of a set into given classes, but referring to several elements he does not know to which classes th...

Within a semiparametric framework we propose a test of shape invariance of Engel curves, which is a necessary condition for base independence. Using Canadian family expenditure data for 1996 we reject shape invariance for the fuel and clothing share equations. ∗The first author would like to acknowledge SSHRC of Canada for financial support.

We consider the practical problem of constructing binary space partitions (BSPs) for a set S of n orthogonal, nonintersecting, two-dimensional rectangles in IR3 such that the aspect ratio of each rectangle in S is at most , for some constant 1. We present an n2O(plogn )-time algorithm to build a binary space partition of size n2O(plogn ) for S. We also show that if m of the n rectangles in S ha...

The exchange of chlorinated organic pollutants between air and vegetation in cold, mountain environments was investigated through the extraction of coniferous vegetation and high-volume air samples collected from the Canadian Rocky Mountains during the summers of 1999 and 2000. Concentrations of several compounds in vegetation increased as temperatures decreased, whereas atmospheric concentrati...

Magnesium aluminate spinel is one of the most investigated inert matrix materials, due to its good physico-chemical stability, resistance against neutron irradiation, and its thermal conductivity comparable with conventional UO2 fuel. At the HFR in Petten various combinations of actinides and spinel have been tested within the EFTTRA programme, with the object to study the transmutation of amer...