Aspects of laminar boundary layers

This thesis consists of three parts :- Part I attempts to justify analytically some of Hartree's numerical findings for the Falkner-Skan equation and extends some of the results previously obtained by Stewartson to cover the cases of suction and injection. Part II treats the problem of the flat plate in a uniform incompressible stream when there is homogeneous normal injection through the plate. A solution of the boundary layer equations valid in the neighbourhood of the separation point is found. Part III is concerned with the numerical solution of the boundary layer equations for the problem in Part II. Results in the form of tables and graphs are given

Existentialism, Choice, and Morality in Ichikawa Kon’s Fires on the Plain

In this essay I explain how the protagonist of Ichikawa Kon's film Fires on the Plain, Tamura, embodies the essence of humanism. The story portrays the development of an unassuming army private as he refuses to accept the fate his superiors have chosen for him. For Tamura, the ability to determine his own actions becomes his resolve. He achieves this by acknowledging the power of choice within himself, a fundamental notion of humanism that he develops throughout the film. In this paper I propose that the character of Tamura, through his personal decision making, is a living allegory for humanism. To support this thesis, I cite specific scenes in the film that reflect the protagonist's evolution from dogmatist to humanist and link them with their corresponding elements of humanism. In conclusion, I find that Tamura effectively represents the functionality of humanism as defined by a selection of modern thinkers

High-field charge transport and noise in p-Si from first principles

The parameter-free computation of charge transport properties of semiconductors is now routine owing to advances in the ab-initio description of the electron-phonon interaction. Many studies focus on the low-field regime in which the carrier temperature equals the lattice temperature and the current power spectral density (PSD) is proportional to the mobility. The calculation of high-field transport and noise properties offers a stricter test of the theory as these relations no longer hold, yet few such calculations have been reported. Here, we compute the high-field mobility and PSD of hot holes in silicon from first principles at temperatures of 77 and 300 K and electric fields up to 20 kV cm$^{-1}$ along various crystallographic axes. We find that the calculations quantitatively reproduce experimental trends including the anisotropy and electric-field dependence of hole mobility and PSD. The experimentally observed rapid variation of energy relaxation time with electric field at cryogenic temperatures is also correctly predicted. However, as in low-field studies, absolute quantitative agreement is in general lacking, a discrepancy that has been attributed to inaccuracies in the calculated valence band structure. Our work highlights the use of high-field transport and noise properties as a rigorous test of the theory of electron-phonon interactions in semiconductors.Comment: 19 pages, 4 figure

Surface Instabilities on Liquid Oxygen in an Inhomogeneous Magnetic Field

Liquid oxygen exhibits surface instabilities when subjected to a sufficiently strong magnetic field. A vertically oriented magnetic field gradient both increases the magnetic field value at which the pattern forms and shrinks the length scale of the surface patterning. We show that these effects of the field gradient may be described in terms of an ``effective gravity'', which in our experiments may be varied from 1g to 360g.Comment: 4 pages, 5 embedded figures in eps forma

Hot hole transport and noise phenomena in silicon at cryogenic temperatures from first principles

The transport properties of hot holes in silicon at cryogenic temperatures exhibit several anomalous features, including the emergence of two distinct saturated drift velocity regimes and a non-monotonic trend of the current noise versus electric field at microwave frequencies. Despite prior investigations, these features lack generally accepted explanations. Here, we examine the microscopic origin of these phenomena by extending a recently developed ab-initio theory of high-field transport and noise in semiconductors. We find that the drift velocity anomaly may be attributed to scattering dominated by acoustic phonon emission, leading to an additional regime of drift velocity saturation at temperatures $\sim 40$ K for which the acoustic phonon occupation is negligible; while the non-monotonic trend in the current noise arises due to the decrease in momentum relaxation time with electric field. The former conclusion is consistent with the findings of prior work, but the latter distinctly differs from previous explanations. This work highlights the use of high-field transport and noise phenomena as sensitive probes of microscopic charge transport phenomena in semiconductors.Comment: 19 pages, 4 figure

Constructions of Clinical Psychology in Adult Mental Health: A Discursive Thematic Analysis

In face of the current economic-political changes facing the UK and its State institutions and of the new evidence about the impact of social inequality on human distress, this study attempts to understand the increasing practice of delivering psychological therapy by the British clinical psychology profession. A review of the critical histories of the profession in the UK identified the need for a more detailed study of the “history of the present” to reveal the discursive operations that construct professional practice. A discursive thematic analysis (DTA) based on the theoretical concepts of the late post-modern scholar Michel Foucault was used to explore public available documents produced by British clinical psychologists between 2010 and 2014. Two dominant professional discursive themes were identified: alternative and leadership. These themes were found to be supported by the discursive sub-themes of applied science, well-being, Cognitivism and therapy which align the aspiration of the profession with those of the State. The tension between the applied scientist and the therapist role - specifically the need to establish simultaneously the profession’s scientific credibility and its therapeutic abilities in order to respond to market pressures – showed recurrences of the conflicts of the early history of professionalization of clinical psychology. The positioning of clinical psychology against the use of functional psychiatric diagnosis and the challenges and opportunities identified by the opening of the NHS market to ‘any willing provider’ revealed how professional discourses operate to maintain the status quo. This study recommends that the socio-historical construction of the profession should be investigated further, in particular through the subjugated discourse identified her

Student perceptions on skills and learning challenges in the use of educational technology in a low-contact, blended and professional learning context: a grounded theory of ‘improvised learning’

This research project provides an original contribution to knowledge, comprising a grounded and unified theory of improvisational behaviours via Blended Learning and suggests a new paradigm of self-regulated, improvisational learning for potential application beyond the field of study. The study comprises an original Grounded Theory of ‘Improvised Learning’ demonstrating the most prevalent challenges, strategies and behaviours of students undertaking Higher Education programmes in a campus-based, low-contact teaching environment. The participant group were typically undertaking accredited professional programmes (usually related to a profession such as nursing or accounting). The students engaged in ‘Blended Learning’ i.e. study on-campus alongside use of learning technologies such as a Virtual Learning Environment (VLE). The research project used Grounded Theory as an holistic methodology to investigate the experience of students in this study context. The main data collection phase consisted of informal individual or group discussions held in classes, open plan Library areas or IT Labs. Grounded Theory is a sociological methodology designed to formulate a new (Grounded) theory from a ‘substantive area’, i.e. a participant group typically comprising a shared vocational role or activity. Key elements of Grounded Theory include an emphasis on induction-based conceptualisation of theory from descriptive participant indicators and the continuous comparison of data for the emergence of ‘theoretical categories’ or codes. The ultimate aim of Grounded Theory is to demonstrate how conceptual categories inter-relate within a common theoretical explanation for the behaviour of participants (the ‘core category’). This grounded study of professional learners identified a number of theoretical models of behaviour for engaging with Blended Learning, including innovative self-led use of Information Technology and collaborative learning. The emergent ‘core category’ - reflecting all dependant codes or variables was defined as ‘Improvised Learning’, explaining conceptually how students employ self-led strategies and skills to engage with disparate systems, environments and resources