FPGAs are attractive devices as they enable the designer to make changes to the system during its lifetime. This is important in the early stages of development when all the details of the final system might not be known yet. In a research environment like at CERN there are many FPGAs used for this very reason and also because they enable high speed communication and processing. The biggest problem at CERN is that the systems might have to operate in a radioactive envi- ronment which is very harsh on electronics. ASICs can be designed to withstand high levels of radiation and are used in many places but they are expensive in terms of cost and time and they are not very flexible. There is therefore a need to understand if it is possible to use FPGAs in these places or what needs to be done to make it possible. Mitigation techniques can be used to avoid that a fault caused by radiation is disrupting the system. How this can be done and the importance of under- standing the underlying architecture of the FPGA is discussed in this thesis. A simulation tool used for injecting faults into the design is proposed in order to verify that the techniques used are working as expected which might not always be the case. The methods used during simulation which provided the best protec- tion against faults is added to a system design which is implemented on a flash based FPGA mounted on a board. This board was installed in the CERN Proton Synchrotron for 99 days during which the system was continuously monitored. During this time 11 faults were detected and the system was still functional at the end of the test. The result from the simulation and hardware test shows that with reasonable effort it is possible to use commercially available FPGAs in a radioactive environment.

Remorse can be a powerful source of mitigation at sentencing. However, there is a lack of formal justification for this practice and a paucity of theoretical literature engaging with this issue. Addressing this gap, this thesis offers a comprehensive justification for why an offender’s remorse should mitigate the punishment he receives. It begins by discussing the emotion of remorse – its nature and value. With reference to broadly-retributive theories of punishment, it then considers various arguments that could be offered to justify the mitigating effect of remorse on the offender’s sentence. It rejects two arguments: either remorse constitutes some of the offender’s deserved punishment or remorse reduces the seriousness of the offence. Instead, it develops a justification inspired by philosophical work distinguishing blameworthiness and blaming. The thesis argues that, in the context of sentencing, a broadly-conceived dialogical model of censure is the most legitimate. Remorse, as the offender’s ideal input into the dialogue about the offence, modifies the subsequent censure required. If censure seeks a response, and this response is already forthcoming, to nonetheless continue to seek this response as if it were absent devalues the censure. Von Hirsch and Ashworth’s assertions that censure appeals to the offender as a rational moral agent, and their adherence to certain quasiretributive values, are shown to provide further support for these arguments. If the deserved censure is mitigated, then so is the corresponding punishment communicating this censure. The thesis next explores how this justification for mitigation compares with ‘mercy’ justifications, arguing that the justification offered in this thesis operates more internally to deserved censure, and is more principled, so is preferable on these grounds. In conclusion, the thesis considers the implications of its arguments for sentencing practice and whether it is a concern that they are valid only within ‘censure’ theories of punishment.

South Louisiana regularly experiences effects from flooding. This study looks at what homeowners are doing to reduce their losses from floods through the practices of flood mitigation. I developed four hypotheses to predict homeowners' mitigation behavior. (1) Homeowners with a history of flooding are likely to mitigate more than those without previous flooding. (2) High-disposable-income homeowners are more likely to mitigate than lowdisposable- income homeowners. (3) The stronger the place attachment among homeowners, the higher the likelihood they will mitigate. (4) Homeowners who have experienced effective mitigation measures in the past are more likely to mitigate than those who have not. To test these hypotheses, a survey was administered in five different neighborhoods throughout Orleans and Jefferson parishes having high concentrations of repeatedly flooded homes. The findings suggest severity of past flooding, disposable savings, strong relationships with neighbors, and discussion of flooding with neighbors are the strongest predictors of flood mitigation.

Passive vibration mitigation via multi-stable, mechanical means is relatively unexplored. In addition, achieving vibration suppression through avoiding resonance is at the forefront of up and coming research. This thesis investigates the application of a purely mechanical, bistable device as a passive method of vibration suppression. A purely mechanical device does not require power, multiple materials, or electrical circuits, and a passive device does not require external interaction or control. Therefore, a passive, mechanical device could be implemented with ease even in physically constrained environments with large dynamic loads, such as turbomachinery. The purely mechanical, bistable device presented herein replicates the two switches per resonance crossing evident in semi-active Resonance Frequency Detuning method. This work explores two different bistable, mass-spring models. The first is a single degree of freedom nonlinear mass spring model aiming to utilize asymmetry in the potential function to change the stiffness of the overall system. The second model is a coupled, two degree of freedom system that combines the nonlinear softening and hardening spring characteristics with the unique stiffnesses of two stable states. The performance is verified by targeting the first mode of a cantilever beam, with the device shifting the resonance away from the excitation frequency. Future research could apply these idealized models to complex, rotating structures and replicate the performance of the passive, mechanical devices in a physical geometry that could be manufactured as a part of a target structure.

A dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Master of Science in Engineering. 9 February, 2017 / Global climate change and other environmental disasters have been attributed to continuous anthropogenic carbon dioxide (CO2) emission into the atmosphere. Today, researchers are constantly seeking measures to reduce anthropogenic CO2 emission. Traditionally, absorption technology with use of monoethanolamine (MEA) is used for separating / capturing of anthropogenic CO2. However, the use of MEA is associated with numerous shortcomings, including inefficient energy usage, high operating and capital cost, amine degradation, solvent loss and excessive equipment corrosion. Alternatively, zeolite based membrane systems are promising technique that prove handy and useful than the traditional processes (absorption with monoethanolamine). However, zeolitic membranes with zeolite coating on the supports (i.e. thin-film supported zeolite membranes) are susceptible to abrasion and thermal shock at elevated temperatures due to temperature mismatch between the supports and the membranes, making them to lose selectivity at early stages. On the contrary, nanocomposite architecture membranes, synthesized via pore-plugging hydrothermal route, are more thermally stable and membrane defects are controlled. Nanocomposite zeolite (sodalite) membranes have been proposed for gas separations, most importantly in the separation of H2/CO2, a major component in pre-combustion carbon capture. In addition, sodalite, a porous crystalline zeolite made up of cubic array of β-cages as primary building block having cage aperture in the range of 0.26 and 0.29 nm, is a potential candidate for the separation/purification of light molecules such as hydrogen which has a cage aperture of 0.27 nm under certain process conditions. In this work, nanocomposite architecture hydroxy sodalite membrane with sodalite crystals embedded within α-alumina tubes were successfully synthesized using the pore-plugging hydrothermal synthesis technique and characterized using techniques such as scanning electron microscopy (SEM) and X-ray diffraction (XRD). The morphology of the synthesized membranes shows that sodalite crystals were indeed grown within the porous structures of the support. Furthermore, Basic Desorption Quality Test (BDQT) and gas separation measurement were conducted to evaluate the quality of the as-synthesized membrane in industrial gas separation applications. The effects of operating variables such as pressure at 1.1 bar, 2.0 bar and 3.0 bar. Also, the effects of temperature were conducted on the nanocomposite membrane at 373 K, 423 K and 473 K. Finally, the gases permeation results were fitted with the well-known Maxwell-Stefan model. Results indicated that, the nanocomposite sodalite / ceramic membrane is a potential candidate for removal of H2 from H2/CO2 mixture. The gas permeation measurement from the one-stage nanocomposite membrane shows that the membrane displayed H2 and CO2 permeance of 3.9 x 10-7 mols-1m-2Pa-1 and 8.4 x 10-8 mols-1m-2Pa-1, respectively. However, the morphology of two-stage nanocomposite membrane shows that the support was more plugged with sodalite crystals and the permeance of H2 and CO2 were 7.4 x 10-8 mol.s-1.m-2.Pa-1 and 1.1 x 10-8 mol.s-1.m-2.Pa-1, respectively. Consequently, the H2/CO2 ideal selectivity for the one-stage nanocomposite membrane improved from 4.6 to 6.5 in the two-stage nanocomposite membrane. In conclusion, the two-stage synthesized membrane shows better improvement. The porous support was well plugged and separation performance was evaluated. However, occluded organic matters present in the cages of hydroxy sodalite could have adverse effect on the gas permeation performance of the membrane. It is expected that an organic-free sodalite supported membrane (such as silica sodalite supported membrane) could out-perform the hydroxy sodalite supported membrane reported in this work in term of membrane flux because there will be enough pore space for gas permeation. / MT2017

Arsenic is a prevalent contaminant at a large fraction of US Superfund sites. Therefore, establishing techniques for accelerating As remediation could benefit many contaminated sites. Remediation of As contaminated groundwater by conventional methods, i.e. pump and treat (P&T), can be impeded by slow desorption of As from Fe and Al (hydr)oxides in aquifer solids. Through experimentation at different physical scales (grain, bench, and field scale), the potential for chemical additions to increase As release from sediments and possibly accelerate P&T remediation is examined. The work described here focuses on As contamination and remediation at the Vineland Chemical Co. Superfund site in southern NJ. The site is extensively contaminated with As resulting from decades of poor chemical storage and disposal practices by the Vineland Chemical Co., which manufactured As-based biocides from 1949-1994. Despite significant intervention, including groundwater remediation by P&T and treatment of solids via soil washing, sufficient site clean up could require many decades with current technologies. Chemical amendments that either compete with As for sorption sites or dissolve Fe and Al (hydr)oxides can increase As mobility and potentially improve P&T remediation efficiency. Simple extrapolations from bench scale column experiments based on pore volumes suggest that treatment with 10 mM oxalic acid could lower the time necessary for clean up at the Vineland site from 600 years (with current techniques involving just groundwater) to potentially on the order of 4 years. Small scale (<1 mm2) X-ray fluorescence maps from columns performed within the synchrotron beamline showed As release during oxalic acid treatment that was consistent with the bulk column materials and suggested that microscale processes can be predictive of the larger system. Finally, during a 3-month pilot study at the Vineland site, oxalic acid was injected into a section of the aquifer via an injection manifold system that was designed and built for the experiment. Groundwater samples indicate that introduction of oxalic acid led to increased As release at a sampling well and pump and treat recovery well in the study area. Addition of oxalic acid shows promise for accelerating treatment of a highly contaminated site.

O objetivo desta dissertação é estimar os impactos econômicos de cenários de políticas climáticas para o Brasil. Mais especificamente, pretende-se através de um modelo de equilíbrio geral computável verificar como algumas variáveis econômicas respondem à simulação de algumas políticas de mitigação de mudanças climáticas por parte do Brasil. Para tal propósito, utilizou-se o modelo Emissions Prediction and Policy Analysis EPPA do MIT, o qual é um modelo dinâmico-recursivo, multi-regional que representa a economia mundial. Os principais resultados revelaram que a introdução de metas de redução de emissões a partir de 2015, possibilita uma redução expressiva das emissões de GEEs do país, com destaque para a redução proveniente de desmatamento. Quanto ao nível de atividade econômica verificou-se que o sacrifício a ser realizado em termos de perdas do PIB não se mostrou expressivo, o que pode ser explicado por uma matriz energética intensiva em fontes de energia limpa. Em termos de bem-estar, observou-se que a inclusão de metas de redução do desmatamento, como as representadas pela política CP1 trouxeram perdas modestas em bem-estar para o Brasil, ou seja, o esforço no sentido de enquadramento com as metas de Copenhague é benéfico, pois as perdas de bem-estar serão relativamente pequenas, caso o país continue o ritmo de redução em emissões previsto para 2020. / The objective of this dissertation is to estimate the economic impacts of climate policy scenarios for Brazil. More specifically, it is intended through a computable general equilibrium model to see how some economic variables respond to the simulation of some policies to mitigate climate change by Brazil. For this purpose, it was used the Emissions Prediction and Policy Analysis model EPPA, from the MIT, which is a dynamic-recursive model, multi-regional that represents the world economy. The results reveal that the introduction of the targets for reducing emissions from 2015, allows an expressive reduction of GHG emissions in the country, notably the reduction from deforestation. Regarding the level of economic activity showed that the sacrifice being made in terms of GDP loss was not significant, which can be explained by an energy-intensive sources of clean energy. In terms of welfare, it was observed that the inclusion of the targets for reducing deforestation, such as those represented by the policy CP1 brought modest losses in welfare for Brazil, namely the effort to frame the goals of Copenhagen is beneficial, because the loss of welfare will be relatively small if the country can continue the pace of reduction in emissions in 2020.

Within the context of the 2007/2008 subprime crisis, we examine the impact and relevance of previous ex ante residential mortgage research to prevent and mitigate mortgage default and develop a general taxonomy of (ex-ante) government intervention. We continue by investigating the various forms of (ex-post) default mitigation options prevalent in the United States and innovatively categorise them into one of three categories based on whether the mortgage contract has been renegotiated. We examine the strategic renegotiation option, alongside the more traditional ruthless or strategic default option, for a US owner-occupier residential mortgage holder and non-owner occupier residential mortgage holder uniquely deriving closed form solutions to calculate the optimal ex-ante LTV (Loan to Value) and ex-post exercise moment where a heterogeneous borrower exercises a renegotiation option. We finally relax the perpetual ability to pay assumption underlying strategic default and negotiation to investigate default and negotiation triggered by both an inability to pay and unwillingness to pay. We simulate the overall effect of (institutionalised) renegotiation under these two assumptions, comparing the effect of a stylised HAMP program on the overall default, foreclosure and prepayment probabilities of owner occupied residential homeowners in the absence of a HAMP program. We conclude that the traditional option theoretic assumption that homeowners "can always pay" is a very strong assumption the consequence of which could induce relevant policy makers to incorrectly interpret and act on conclusions and recommendations flowing from historical option theoretic mortgage research.

There is a growing body of literature recognizing the benefits of Open Data. However, many potential data providers are unwilling to publish their data and at the same time, data users are often faced with difficulties when attempting to use Open Data in practice. Despite various barriers in using and publishing Open Data still being present, studies which systematically collect and assess these barriers are rare. Based on this observation we present a review on prior literature on barriers and the results of an empirical study aimed at assessing both the users' and publishers' views on obstacles regarding Open Data adoption. We collected data with an online survey in Austria and internationally. Using a sample of 183 participants, we draw conclusions about the relative importance of the barriers reported in the literature. In comparison to a previous conference paper presented at the conference for E-Democracy and Open Government, this article includes new additional data from participants outside Austria, reports new analyses, and substantially extends the discussion of results and of possible strategies for the mitigation of Open Data barriers.

Radio astronomical synthesis imaging arrays can create images with resolution much higher than can single dish telescopes. However, one of the biggest problems that imaging arrays face is radio frequency interference (RFI). This interference corrupts signals and prevents accurate image creation. Therefore, it is necessary to remove this interference. This thesis discusses the synthesis imaging procedure and array spatial filter­ing methods to remove interference, including Multiple Sidelobe Canceller (MSC), Subspace Projection (SP), and Cross­-Subspace Projection (CSP). The CLEAN algorithm, an image restoration technique, is also discussed. Various improvements to the VSA are discussed, including upgrades to the hardware and software and addition of a fifth antenna to the array. Calibration techniques for the VSA are presented. Successful image synthesis for deep-­space sources of Cassiopeia A and Cygnus A are shown and phase errors that have caused difficulties with imaging are considered. The previously mentioned algorithms are successfully applied to data gathered by the Very Small Array (VSA), allowing images to be created in environments with interference. An improved method for bias correction for both SP and CSP is demonstrated. The CLEAN algorithm is demonstrated on two different images.