Let G be a connected linear Lie group which finitely covers the isometry group of X. Furthermore, let Γ ⊂ G be a discrete subgroup. We assume that Γ is geometrically finite. We refer to Definition 2.1 for a precise explanation of this notion. If X is a real hyperbolic space, then Γ is geometrically finite iff it admits a fundamental domain with finitely many totally geodesic faces. In the other...

Introduction A major concern about the use of information and communication technology (ICT) in adult education is that the digital divide may reinforce the already existing learning divide, because it runs along the same lines of socio-economic class, gender and ethnicity (eg, Gorard & Selwyn, 2005). Many researchers report a socio-economic digital divide, as well as a gender gap, although the...

In this paper we construct a faithful representation of the mapping class group of the genus two surface into a group of matrices over the complex numbers. Our starting point is the Lawrence-Krammer representation of the braid group Bn , which was shown to be faithful by Bigelow and Krammer. We obtain a faithful representation of the mapping class group of the n-punctured sphere by using the cl...

We compare open loop versus closed loop identiication when the identiied model is used for control design, and when the system itself belongs to the model class, so that only variance errors are relevant. For three diierent control design criteria (minimum variance, LQG and model reference control) we show that, under those conditions, a better performance is achieved by closing the loop during...

Given a code from a shift space to an irreducible sofic shift, any two of the following three conditions – open, constant-to-one, (right or left) closing – imply the third. If the range is not sofic, then the same result holds when bi-closingness replaces closingness. Properties of open mappings between shift spaces are investigated in detail. In particular, we show that a closing open (or cons...

A report arising from a study carried out in the academic year 1997–1998 and commissioned by the Higher Education Quality Council (subsequently the Quality Assurance Agency). The views expressed are those of the authors and are not necessarily those of the Scottish Council for Research in Education or the Quality Assurance Agency.

modelling of crack propagation by finite element method under mixed mode conditions is of prime importance in fracture mechanics. this paper describes an application of finite element method to the analysis of mixed mode crack growth in linear elastic fracture mechanics. crack growth process is simulated by an incremental crack-extension analysis based on the maximum principal stress criterion,...

OBJECTIVES HIV prevalence among people who inject drugs (PWID) in Ottawa is estimated at about 10%. The successful integration of peers into outreach efforts and wider access to HIV point-of-care testing (POCT) create opportunities to explore the role of peers in providing HIV testing. The PROUD study, in partnership with Ottawa Public Health (OPH), sought to develop a model for community-based...

OBJECTIVE To examine relationships between parenting behaviors, parent-child relationship, and moderating effects of age on youth substance use among a community sample of African-American mothers who use crack cocaine and their children (12-17 years). METHODS Maternal-child dyads (n = 208) were recruited through street outreach and snowball sampling and completed interviews about substance u...