Not available / text

Let E be an elementary abelian p-group of rank r and k an algebraically closed field of characteristic p. We investigate finitely generated kE-modules of stable constant Jordan type [a][b] with 1 ≤ a, b ≤ p − 1 using the functors Fi from finitely generated kE-modules to vector bundles on the projective space Pr−1 constructed by Benson and Pevtsova. In particular, we study relations on the Chern numbers of the trivial bundle M to obtain restrictions on a and b for sufficiently large ranks and primes. We then study kE-modules with the constant image property and define the constant image layers of a module with respect to its maximal submodule having the constant image property. We prove that almost all such subquotients are semisimple. Focusing on the class of W-modules in rank two, we also calculate the vector bundles Fi(M) for all W-modules M. For E of rank two, we derive a duality formula for kE-modules M of constant Jordan type and their generic kernels K(M). We use this to answer a question of Carlson, Friedlander and Suslin regarding whether or not the submodules J−iK(M) also have constant Jordan type for all i ≥ 0. We show that this question has an affirmative answer whenever p = 3 or J2K(M) = 0. We also show that it has a negative answer in general by constructing a kE-module M of constant Jordan type for p ≥ 5 such that J−1K(M) does not have constant Jordan type. Finally, we use ideas from a theorem of Benson to show that if M is a kE-module of constant Jordan type containing no Jordan blocks of length one, then there always exist submodules of J−1K(M)/J2K(M) having a particularly nice structure.

No description available.

This thesis reports an exploration of how the use and construction of external representations through methods of signalling and conversational grounding, support the sharing of ideas for spatial design tasks and how that support changes as a function of access to a shared works pace, external representations and memory support. Further aims of the study were to develop a coding scheme to identify the use of language in establishing and maintaining mutual understanding between collaborators. Pilot studies identified appropriate tasks relating to visual problem-solving design tasks for use in the main studies. For the main studies, video recordings were obtained, coded and time-stamped and analysis of the duration of grounding and activity codes, as well as concurrent grounding and activity, was carried on the impact of tasks and constraints on communication. For the first study 36 pairs of participants were used to investigate collaborative problem-solving and visual access to a shared workspace was varied. For the second study, 30 pairs of participants were used to investigate how ‘learned’ solutions are communicated. Again visual access to a shared workspace was varied, together with the manipulation of the opportunity for communicators to have access to external representations and memory support. Evidence was obtained to support the principles of ‘co-operation' and 'least collaborative effort' in conversation. Differences in the use and construction of external representations were discussed in terms of compensations, and changes in dyadic interactivity, made as a function of limitations in the media settings and the purpose of the joint activity. Other issues emerged relating to perceived communication efficacy as a result of a divided workspace focus and competition between problem-solving and grounding resources. These findings have implications for design cognition and communication as well as the technological support offered to support such activities.

No description available.

Thesis (Ph. D.)--McMaster University (Canada), 1993. / Source: Dissertation Abstracts International, Volume: 54-12, Section: B, page: 6240. Adviser: V.P. Snaith.

Thesis--Bonn. / Extra t.p. with thesis statement inserted. Includes bibliographical references (p. 107-108).

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 37-38). Also available in electronic version. Access restricted to campus users.

Thesis--Bonn. / Extra t.p. with thesis statement inserted. Includes bibliographical references (p. 107-108).

Thesis (Ph. D.)--University of Texas at Austin, 2003. / Vita. Includes bibliographical references. Available also from UMI Company.