Incremental analysis of large elastic deformation of a rotating cylinder

The effect of finite deformation upon a rotating, orthotropic cylinder was investigated using a general incremental theory. The incremental equations of motion are developed using the variational principle. The governing equations are derived using the principle of virtual work for a body with initial stress. The governing equations are reduced to those for the title problem and a numerical solution is obtained using finite difference approximations. Since the problem is defined in terms of one independent space coordinate, the finite difference grid can be modified as the incremental deformation occurs without serious numerical difficulties. The nonlinear problem is solved incrementally by totaling a series of linear solutions

Research on knowledge representation, machine learning, and knowledge acquisition

Research in knowledge representation, machine learning, and knowledge acquisition performed at Knowledge Systems Lab. is summarized. The major goal of the research was to develop flexible, effective methods for representing the qualitative knowledge necessary for solving large problems that require symbolic reasoning as well as numerical computation. The research focused on integrating different representation methods to describe different kinds of knowledge more effectively than any one method can alone. In particular, emphasis was placed on representing and using spatial information about three dimensional objects and constraints on the arrangement of these objects in space. Another major theme is the development of robust machine learning programs that can be integrated with a variety of intelligent systems. To achieve this goal, learning methods were designed, implemented and experimented within several different problem solving environments

Integrating information seeking and information structuring: spatial hypertext as an interface to the digital library.

Information seeking is the task of finding documents that satisfy the information needs of a person or organisation. Digital Libraries are one means of providing documents to meet the information needs of their users - i.e. as a resource to support information seeking. Therefore, research into the activity of information seeking is key to the development and understanding of digital libraries. Information structuring is the activity of organising documents found in the process of information seeking. Information structuring can be seen as either part of information seeking, or as a sepárate, complementary activity. It is a task performed by the seeker themselves and targeted by them to support their understanding and the management of later seeking activity. Though information structuring is an important task, it receives sparse support in current digital library Systems. Spatial hypertexts are computer software Systems that have been specifically been developed to support information structuring. However, they seldom are connected to Systems that support information seeking. Thus to day, the two inter-related activities of information seeking and information structuring have been supported by disjoint computer Systems. However, a variety of research strongly indicates that in physical environments, information seeking and information structuring are closely inter-related activities. Given this connection, this thesis explores whether a similar relationship can be found in electronic information seeking environments. However, given the absence of a software system that supports both activities well, there is an immédiate practical problem. In this thesis, I introduce an integrated information seeking and structuring System, called Garnet, that provides a spatial hypertext interface that also supports information seeking in a digital library. The opportunity of supporting information seeking by the artefacts of information structuring is explored in the Garnet system, drawing on the benefits previously found in supporting one information seeking activity with the artefacts of another. Garnet and its use are studied in a qualitative user study that results in the comparison of user behaviour in a combined electronic environment with previous studies in physical environments. The response of participants to using Garnet is reported, particularly regarding their perceptions of the combined system and the quality of the interaction. Finally, the potential value of the artefacts of information structuring to support information seeking is also evaluated

Take Me Out: Space and Place in Library Interactions

Information interactions are strongly affected by the place where they occur. Specific locations are ofen associated with searches on particular topics, and individual users perform different tasks in habituated places. A classic example of habituated space is the commuter who regularly reads the news on the train. This paper investigates these associations through four user studies that examine different uses of place in information interaction. Through this, we reveal the ways in which the location of information interactions makes them effective or ineffective. This extends our interpretation of the role of place in information interaction beyond established foci such as location-based search

Getting creative in everyday life: Investigating arts and crafts hobbyists' information behavior

While there has been increasing interest in how creative professionals find information to drive creative outputs, previous information behavior research has largely ignored how arts and crafts hobbyists look for information sources in their everyday lives. To fill this literature gap, we conducted interviews and observations with arts and crafts hobbyists to find out how they conceive potential DIY projects. The findings highlight three themes: the dearth of human sources, the prevalence of domain-specific information, and the use of self-curated information. In addition to empirical results, this work also broadens the understanding of information behavior in an arts and crafts context by studying populations beyond professional artists