Homogenization studies for optical sensors based on sculptured thin films

In this thesis we investigate theoretically various types of sculptured thin film (STF) envi�sioned as platforms for optical sensing. A STF consists of an array of parallel nanowires which can be grown on a substrate using vapour deposition techniques. Typically, each nanowire has a diameter in the range from ∼ 10−300 nm while the film thickness is . 1µm. Through careful control of the fabrication process, both the optical properties and the porosity of the STF can be tailored to order. These abilities make STFs promising for optical sensing applications, wherein it is envisaged that the material to be sensed infiltrates the void re�gion in between the parallel nanowires and hence changes the optical properties of the STF. Various homogenization formalisms can be used to estimate the constitutive parameters of the infiltrated STFs. In this thesis two different homogenization formalisms were used: the Bruggeman formalism (extended and non–extended versions) and the strong-permittivity�fluctuation theory (SPFT). These were used in investigations of the following optical–sensing scenarios: (i) Electromagnetic radiation emitted by a dipole source inside an infiltrated chiral STF. The effects of using the extended Bruggeman homogenization formalism, which takes into account the nonzero size of the component particles, were studied. (ii) Surface–plasmon– polariton waves on a metal–coated, infiltrated columnar thin film. The influences of using the extended SPFT formalism, which takes into account the nonzero size of the component particles and their statistical distributions, were explored. (iii) A metal-coated infiltrated chiral STF which supports both surface-plasmon-polariton waves and the circular Bragg phe�nomenon. The possibility of using in parallel both surface-plasmon-polariton waves and the circular Bragg phenomenon was investigated using the non–extended Bruggeman formalism. Our numerical studies revealed that the design performance parameters of the infiltrated STF are bode well for these optical–sensing scenarios. The use of inverse Bruggeman formalism was also investigated: this was found to be problematic in certain constitutive parameter regimes, but not those for optical–sensing scenarios considered in this thesis

Day-in-a-life microethnographies and favourite things interviews

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Postmodern synergistic knowledge creation:Extending the boundaries of disability studies

The tensions between the competing discourses of the medical and the social models of disability have traditionally provided a platform for discussion and research in the fields of disability studies and special needs education. Over the last 30 years a wealth of literature has consolidated the debate and produced particular knowledge of impairment and disability. In this paper we argue that by privileging notions of 'deficit' within these medical or social model perspectives the richness of the lived experience of people with impairments is denied. The individual becomes lost within a framework of medical symptoms or social inequalities. This paper considers alternative approaches which reveal a fuller picture of the lives of people with impairments. The authors conducted two separate empirical studies, one employing a Deleuzo-Guattarian perspective, the other a Bourdieusian perspective. In this paper we illustrate how these theories of practice can reveal situated understandings of the individual with impairments and his/her daily life. By embracing new understandings and different theoretical perspectives we show how new knowledge can emerge to illuminate the fluid and ever-changing notions of 'disability', 'inclusion' and 'exclusion', which form elements of the individual lived experience of the research participants

Creative interactions with data: using visual and metaphorical devices in repeated focus groups

This article presents some of the emergent methods developed to fit a study of quality in inclusive research with people with learning disabilities. It addresses (i) the ways in which the methodology was a response to the need for constructive, transformative dialogue through useof repeated focus groups in a design interspersing dialogic and reflective spaces; and (ii) how stimulus materials for the focus groups involved imaginative and creative interactions with data. Particular innovations in the blending of narrative and thematic analyses and data generation and analysis processes are explored, specifically the creative use of metaphor as stimulus and the playful adaptation of I-poems from the Listening Guide approach as writing and performance. In reflecting on these methodological turns we also reflect on creativity as an interpretive lens. The paper is an invitation for further methodological dialogue and development