Visual object-oriented development of parallel applications

PhD ThesisDeveloping software for parallel architectures is a notoriously difficult task, compounded further by the range of available parallel architectures. There has been little research effort invested in how to engineer parallel applications for more general problem domains than the traditional numerically intensive domain. This thesis addresses these issues. An object-oriented paradigm for the development of general-purpose parallel applications, with full lifecycle support, is proposed and investigated, and a visual programming language to support that paradigm is developed. This thesis presents experiences and results from experiments with this new model for parallel application development.Engineering and Physical Sciences Research Council

On a cylindrical scanning modality in three-dimensional Compton scatter tomography

We present injectivity and microlocal analyses of a new generalized Radon transform, $\mathcal{R}$, which has applications to a novel scanner design in three-dimensional Compton Scattering Tomography (CST), which we also introduce here. Using Fourier decomposition and Volterra equation theory, we prove that $\mathcal{R}$ is injective and show that the image solution is unique. Using microlocal analysis, we prove that $\mathcal{R}$ satisfies the Bolker condition, and we investigate the edge detection capabilities of $\mathcal{R}$. This has important implications regarding the stability of inversion and the amplification of measurement noise. In addition, we present simulated 3-D image reconstructions from $\mathcal{R}f$ data, where $f$ is a 3-D density, with varying levels of added Gaussian noise. This paper provides the theoretical groundwork for 3-D CST using the proposed scanner design.Comment: 23 pages, 9 figures, 1 tabl

This Piece is a Coverup

This Piece is a Coverup follows Ben from his days as a club kid to his role in one of the most notoriously violent prison gangs in the US

HERBVI - a program for simulation of baryon- and lepton- number violating processes

We describe a Monte Carlo event generator for the simulation of baryon- and lepton-number violating processes at supercolliders. The package, {\HERBVI}, is designed as a hard-process generator interfacing to the general hadronic event simulation program {\HW}. In view of the very high multiplicity of gauge bosons expected in such processes, particular attention is paid to the efficient generation of multiparticle phase space. The program also takes account of the expected colour structure of baryon-number violating vertices, which has important implications for the hadronization of the final state.Comment: 19 pages, standard LaTeX, no figure

Health Insurance Benefit Mandates and the Firm-Size Distribution

By 2010, the average US state had passed 37 health insurance benefit mandates (laws requiring health insurance plans to cover certain additional services). Previous work has shown that these mandates likely increase health insurance premiums, which in turn could make it more costly for firms to compensate employees. Using 19962010 data from the Quarterly Census of Employment and Wages and a novel instrumental variables strategy, we show that there is limited evidence that mandates reduce employment. However, we find that mandates lead to a distortion in firm size, benefiting larger firms that are able to self-insure and thus exempt themselves from these state-level health insurance regulations. This distortion in firm size away from small businesses may lead to substantial decreases in productivity and economic growth