41 research outputs found
Advance Australia fair [music] /
No full textNew ed. For chorus (SATB); Caption title.; Issued as a postcard.; "Patriotic song".; "Under Govt. Patronage, N.S.W. & League of the Empire, London. Sung by the Great Choir of 10,000 voices at Commonwealth celebrations ..."; "The words of this patriotic song have been revised. The author, Mr P.D. McCormick ("Amicus"), is indebted to the late Professor Stuart Blackie, of Edinburgh, for improvement in the last verse".; "'Advance Australia Fair' is now our national anthem"-the Premier, May, 1907".; Postcard has stamp dated 5 Feb 1909.; Condition: Fold across centre.; Also available online http://nla.gov.au/nla.mus-vn4193652.Advance Australia fair. Chorus scor
Potential to measure quantum effects in recent all-optical radiation reaction experiments
Get PDFThe construction of 10 PW class laser facilities with unprecedented intensities has emphasized the need for a thorough understanding of the radiation reaction process. We describe simulations for a recent all-optical colliding pulse experiment, where a GeV scale electron bunch produced by a laser wakefield accelerator interacted with a counter-propagating laser pulse. In the rest frame of the electron bunch, the electric field of the laser pulse is increased by several orders of magnitude, approaching the Schwinger field and leading to substantial variation from the classical Landau-Lifshitz model. Our simulations show how the final electron and photon spectra may allow us to differentiate between stochastic and semi-classical models of radiation reaction, even when there is significant shot-to-shot variation in the experimental parameters. In particular, constraints are placed on the maximum energy spread and shot-to-shot variation permissible if a stochastic model is to be proven with confidence
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Measuring signatures in photon angular spectra to distinguish nonlinear Compton scattering models
Get PDFThe collision of a high-energy electron beam with a laser pulse may be used to study radiation reaction and nonlinear Compton scattering among many other processes in strong-field quantum electrodynamics. Predictions from simulation and theory for these interactions rely on a number of approximations and assumptions that have not been experimentally tested. Here, experimentally measurable signatures are identified that might be able to distinguish between radiation reaction models, i.e., classical or quantum, or between the local constant field and local monochromatic approximations used to calculate the properties of the nonlinear Compton process. These signatures are considered through Monte Carlo simulations of various experimental conditions that are relevant to today's laser facilities. Potential detection schemes for measuring the signatures are proposed. We find that single-photon counting of keV photons to resolve harmonics and scintillator-based detection of MeV photons may allow us to validate nonlinear Compton scattering models and radiation reaction models respectively. This will require electron beams with divergence angles less than 2 mrad and less than 20% energy spread
Resilient places? The healthcare gardens and the Maggie's Centres
Get PDFThis thesis takes as its focus the Maggie’s Cancer Centres exploring for the first time the impact of their designed gardens. This research is situated within the immediate context of Maggie’s ambitions as an organisation and looks closely at their design process. It is also set within the wider debates about the effects of green space on health and the historical context of the restorative garden. By exploring both historical and contemporary examples, it argues that a healthcare garden may be a space for transformation.
Using four different Maggie’s gardens as case studies, the research seeks to investigate the role of these outdoor spaces and their impact on users. Through ethnographic and sensory methods, each garden is considered and mapped. It looks at the design brief and the intentions of the designers’, but the core work is an exploration of the experiences of staff and visitors. The focus is on the everyday use of these gardens as well as the design historiography. The experiences of gardens within healthcare are examined in order to expose the ways in which gardens, people, health and care are entwined.
Through the qualitative research process this thesis develops a new hypothesis as to how healthcare gardens may operate – offering a new definition for them as “resilient places”. Careful analysis of the data reveals the specific networks and affordances presented by these gardens. The thesis argues, based on the evidence of users, that healthcare gardens can uniquely embrace certain “essences” where essence is defined as conveying a quality or attribute. These garden essences are identified as thresholds, sensory richness, the density of time and homeliness. The thesis also argues that a healthcare garden can provide specific and unique opportunities for care and this, in turn, can enhance the healing ethos of an organisation such as Maggie’s
Measuring signatures in photon angular spectra to distinguish nonlinear Compton scattering models
Get PDFThe collision of a high-energy electron beam with a laser pulse may be used to study radiation reaction and nonlinear Compton scattering among many other processes in strong-field quantum electrodynamics. Predictions from simulation and theory for these interactions rely on a number of approximations and assumptions that have not been experimentally tested. Here, experimentally measurable signatures are identified that might be able to distinguish between radiation reaction models, i.e., classical or quantum, or between the local constant field and local monochromatic approximations used to calculate the properties of the nonlinear Compton process. These signatures are considered through Monte Carlo simulations of various experimental conditions that are relevant to today's laser facilities. Potential detection schemes for measuring the signatures are proposed. We find that single-photon counting of keV photons to resolve harmonics and scintillator-based detection of MeV photons may allow us to validate nonlinear Compton scattering models and radiation reaction models respectively. This will require electron beams with divergence angles less than 2 mrad and less than 20% energy spread
A Bayesian framework to investigate radiation reaction in strong fields
Get PDFRecent experiments aiming to measure phenomena predicted by strong-field quantum electrodynamics (SFQED) have done so by colliding relativistic electron beams and high-power lasers. In such experiments, measurements of collision parameters are not always feasible. However, precise knowledge of these parameters is required to accurately test SFQED. Here, we present a novel Bayesian inference procedure that infers collision parameters that could not be measured on-shot. This procedure is applicable to all-optical non-linear Compton scattering experiments investigating radiation reaction. The framework allows multiple diagnostics to be combined self-consistently and facilitates the inclusion of known information pertaining to the collision parameters. Using this Bayesian analysis, the relative validity of the classical, quantum-continuous and quantum-stochastic models of radiation reaction was compared for several test cases, which demonstrates the accuracy and model selection capability of the framework and highlight its robustness if the experimental values of fixed parameters differ from their values in the models.</p
Self-injection threshold in self-guided laser wakefield accelerators
Get PDFA laser pulse traveling through a plasma can excite large amplitude plasma waves that can be used to accelerate relativistic electron beams in a very short distance-a technique called laser wakefield acceleration. Many wakefield acceleration experiments rely on the process of wave breaking, or self-injection, to inject electrons into the wave, while other injection techniques rely on operation without self-injection. We present an experimental study into the parameters, including the pulse energy, focal spot quality, and pulse power, that determine whether or not a wakefield accelerator will self-inject. By taking into account the processes of self-focusing and pulse compression we are able to extend a previously described theoretical model, where the minimum bubble size k(p)r(b) required for trapping is not constant but varies slowly with density and find excellent agreement with this model
"Disney is the Tiffany’s and I am the Woolworth's of the business": A critical re-analysis of the business philosophies, production values and studio practices of animator-producer Paul Houlton Terry
No full textThis thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Animator-producer Paul Houlton Terry has been portrayed as having little passion for the animation he produced and being more concerned with making a profit than producing entertaining cartoons with high production values. The purpose of the dissertation is to re-evaluate Terry‘s legacy to animated cartooning by analyzing his business philosophies, production values, and studio practices.
Application of four psychodynamic factors to the early life and career of Terry, 1887-1929, found that his economic decision making was characterized by: an external locus of control, risk-averse financial behaviour, extreme saving behaviour through precaution, and shrewd money management practices. Based on Terry‘s historical responses to twelve major economic, technological, or institutional forces of change for the period 1929-1955, the psychodynamic factors were found to provide accurate explanations for his studio practices and production decisions.
There was no evidence to support the conclusion that three early career disappointments undermined Terry‘s intrinsic motivation to create animated cartoons. Rather, Terry‘s lack of risk taking, external locus of control, tight studio production schedule, desire to compete with neighbour studio Fleischer, difficulty in separating financial rewards from creative processes in animation, and practice of undertaking surveillance measures on staff may have undermined his and his studio‘s creativity. Archival research found Terry to possess strong passions for and to have made significant creative contributions to the field of animation.
Biographical research found that Terry retained a stable nucleus of highly talented artists who dedicated a significant portion of their working careers to the studio. An analysis of the cel aesthetics of a random sample of animated cartoons produced during the years 1930-1955 found that Terry created animated cartoons with above average cel aesthetics when compared to the other studios thereby supporting an inference that Terry was motivated to producing quality crafted animation. Further research is suggested into the role psychodynamic factors and economic decision-making play in the film production process and a clarification of Terry‘s legacy to the field of animated cartoons
Evaluating the Ecological Impacts of Cultivating Genetically Modified Herbicide Tolerant (GMHT) Oilseed Rape and Maize: (2007-B-DS-1-S1) STRIVE Report
No full textThis report is published as part of the Science, Technology, Research and Innovation for the
Environment (STRIVE) Programme 2007–2013.Author has checked copyrigh
Extended X-ray absorption spectroscopy using an ultrashort pulse laboratory-scale laser-plasma accelerator
Get PDFLaser-driven compact particle accelerators can provide ultrashort pulses of broadband X-rays, well suited for undertaking X-ray absorption spectroscopy measurements on a femtosecond timescale. Here the Extended X-ray Absorption Fine Structure (EXAFS) features of the K-edge of a copper sample have been observed over a 250 eV window in a single shot using a laser wakefield accelerator, providing information on both the electronic and ionic structure simultaneously. This capability will allow the investigation of ultrafast processes, and in particular, probing high-energy-density matter and physics far-from-equilibrium where the sample refresh rate is slow and shot number is limited. For example, states that replicate the tremendous pressures and temperatures of planetary bodies or the conditions inside nuclear fusion reactions. Using high-power lasers to pump these samples also has the advantage of being inherently synchronised to the laser-driven X-ray probe. A perspective on the additional strengths of a laboratory-based ultrafast X-ray absorption source is presented
