A spectral-element technique to approximate partial diierential equations on an innnite domain is examined. The method is based on Boyd's mapping of a semi-innnite interval to a nite interval, and it is extended to a variational setting which allows for an implementation using a spectral-element method. By extending the method to a variational form, a straightforward implementation allows for h...

In this paper we consider single elements in rings and nearrings. If R is a (near)ring, x ∈ R is called single if axb = 0 ⇒ ax = 0 or xb = 0. In seeking rings in which each element is single, we are led to consider 0-simple rings, a class which lies between division rings and simple rings. MSC 2000: 16U99 (primary), 16Y30 (secondary)