Musical Sands

A Constitutive Model for Sands

In this paper, an elastoplastic constitutive model is presented for predicting sandy soil behavior under monotonic and cyclic loadings. The model is based on the CJS3 model that takes into account deviatoric and isotropic mechanisms of plasticity. The flow rule in deviatoric mechanism is non-associated and a kinematic hardening law controls the evolution of the yield surface. In the present s...

The shifting sands algorithm

We resolve the problem of small-space approximate selection in random-order streams. Specifically, we present an algorithm that reads the n elements of a set in random order and returns an element whose rank differs from the true median by at most n while storing a constant number of elements and counters at any one time. This is optimal: it was previously shown that achieving better accuracy r...

Sedimentological Analysis of Sands

This paper presents a practical sequence to study sand grains at the macroscopical scale. The approach consists of two mains phases, the recognition of the grains and the assessment of some of its characteristics. The method is validated on the dimensional features by comparison with a sieving procedure through the analysis of eight large sand samples of different locations.

Oil Sands Contaminants

Alberta oil sands development.

P olycyclic aromatic hydrocarbons (PAHs) are a ubiquitous class of hundreds of organic compounds composed of two or more aromatic rings that are released naturally and from human activities. Natural sources of PAHs include forest fires, oil seeps, and volcanic eruptions; anthropogenic sources include burning of fossil fuels and wood, production of coke and charcoal, petroleum refining, and petr...