A Bayesian approach to assess interaction between known risk factors: The risk of lung cancer from exposure to asbestos and smoking

We review the literature on the combined effect of asbestos exposure and smoking on lung cancer, and explore a Bayesian approach to assess evidence of interaction. Previous approaches have focussed on separate tests for an additive or multiplicative relation. We extend these approaches by exploring the strength of evidence for either relation using approaches which allow the data to choose between both models. We then compare the different approaches.

A Personalized Ontology Model for Web Information Gathering

As a model for knowledge description and formalization, ontologies are widely used to represent user profiles in personalized web information gathering. However, when representing user profiles, many models have utilized only knowledge from either a global knowledge base or a user local information. In this paper, a personalized ontology model is proposed for knowledge representation and reasoning over user profiles. This model learns ontological user profiles from both a world knowledge base and user local instance repositories. The ontology model is evaluated by comparing it against benchmark models in web information gathering. The results show that this ontology model is successful.

The meaning of home for Karen and Chin refugees from Burma: An interpretative phenomenological approach

Loss of home is common to all people from a refugee background yet we have little understanding of the diversity of meaning associated with this important concept. A phenomenological approach was used to explore experiences of home amongst Karen and Chin refugees residing in Brisbane. In-depth, semi-structured interviews were conducted with nine participants from Karen and Chin backgrounds. The participants comprised five females and four males (mean age 40 years, median length of time in Australia 1.33 years). Participants described their migration stories, including pre- and post-migration history. Analysis was conducted using interpretative phenomenological analysis. Three superordinate themes, explicating the meaning of home for participants, were identified: home as the experience of a psychological space of safety and retreat; home as the socio-emotional space of relatedness to family; and home as geographical-emotional landscape. Loss of home was experienced as a multidimensional loss associated with emotional and physical disturbances. These findings, based upon a phenomenological paradigm, enhance understanding of the experience of being a refugee and of the suffering engendered by loss of home. They open up the possibility for conceptualizing refugee responses in terms of human suffering and meaning making.

A hybrid approach for resolving the electromagnetic fields inside a waveguide loaded with a lossy medium

In this work a novel hybrid approach is presented that uses a combination of both time domain and frequency domain solution strategies to predict the power distribution within a lossy medium loaded within a waveguide. The problem of determining the electromagnetic fields evolving within the waveguide and the lossy medium is decoupled into two components, one for computing the fields in the waveguide including a coarse representation of the medium (the exterior problem) and one for a detailed resolution of the lossy medium (the interior problem). A previously documented cell-centred Maxwell’s equations numerical solver can be used to resolve the exterior problem accurately in the time domain. Thereafter the discrete Fourier transform can be applied to the computed field data around the interface of the medium to estimate the frequency domain boundary condition in-formation that is needed for closure of the interior problem. Since only the electric fields are required to compute the power distribution generated within the lossy medium, the interior problem can be resolved efficiently using the Helmholtz equation. A consistent cell-centred finite-volume method is then used to discretise this equation on a fine mesh and the underlying large, sparse, complex matrix system is solved for the required electric field using the iterative Krylov subspace based GMRES iterative solver. It will be shown that the hybrid solution methodology works well when a single frequency is considered in the evaluation of the Helmholtz equation in a single mode waveguide. A restriction of the scheme is that the material needs to be sufficiently lossy, so that any penetrating waves in the material are absorbed.