Mathematical modelling and simulation of the thermo-catalytic decomposition of methane for economically improved hydrogen production

The demand for low-emission hydrogen is set to grow as the world transitions to a future hydrogen economy. Unlike current methods of hydrogen production, which largely derive from fossil fuels with unabated emissions, the thermo-catalytic methane decomposition (TCMD) process is a promising intermediate solution that generates no direct carbon dioxide emissions and can bridge the transition to green hydrogen whilst utilising existing gas infrastructure. This process is yet to see widespread adoption, however, due to the high catalyst turnover costs resulting from the inevitable deactivation of the catalyst, which plays a decisive role in the feasibility of the process. In this study, a feasible TCMD process was identified and a simplified mathematical model was developed, which provides a dynamic estimation for the hydrogen production rate and catalyst turnover costs over various process conditions. The work consisted of a parametric study as well as an investigation into the different process modes. Based on the numerous simulation results it was possible to find the optimal process parameters that maximise the hydrogen pro- duction rate and minimise the catalyst turnover costs, therefore increasing the economic potential of the process and hence its commercial viability.

Exploring the Application of Lean Best Practices in Remanufacturing: Empirical Insights into the Benefits and Barriers

Remanufacturing processes have been widely identified as being important elements of a sustainable economy. However, the commercial viability of this product recovery route is significantly influenced by several operational challenges that are different from those that occur in conventional manufacturing. One of the most widely used systematic process improvement methods in conventional manufacturing is lean production, which seeks to minimize all forms of waste throughout an operation. As the academic study of lean best practices in remanufacturing processes is relatively new, there is a lack of knowledge regarding implementation and impact. As such, this paper presents multiple case studies investigating the application of lean methods in industrial remanufacturing operations. These studies focus on the automotive industry, where both conventional and remanufacturing operations have been the leading adopters of lean thinking and practice. The results of the investigation identify specific lean methods that help manage the inherent complexity of the remanufacturing processes, and consequently improve the overall productivity of the process. Similarly, factors that limit the application of lean practices within remanufacturing are also identified and discussed. Matrices for opportunities and threats are developed to enable the simple adoption of these findings. Overall, the research provides a more holistic understanding of the application of lean within a remanufacturing environment, with benefits for both academia and industry.

Recovering the performance of irradiated high temperature superconductors for use in fusion magnets

The magnets confining the plasma in future fusion devices will be exposed to a significant destructive flux of fast neutrons. Particularly, in cost efficient compact reactor designs, the degradation of the superconductor becomes an issue and directly impacts the commercial viability. We report on the influence of neutron radiation on the superconducting transition temperature, Tc, and the critical current density, jc, and discuss possibilities to counteract the degradation by thermal treatments. We found that the degradation in Tc and jc are closely related to each other, likely by the expected loss of superfluid density; thus, Tc is a very useful indicator for the magnets' degradation. It increases linearly with annealing temperature and around 25 % of the decrease can be recovered by annealing at 150 °C and about 60 % at 400 °C, which would more than double the magnet’s life time. However, a loss of oxygen has to be impeded in the latter case.

Electric Power Amplification in Fusion Power Plants

Fusion power concepts that are heated by electrical devices for the purpose of producing high levels of electrical output are in effect electric power amplifiers. Three systems are considered: A hypothetical electric power version of the ITER experiment, the ARIES-1 fusion reactor design, and a modified version of ARIES-1 with stainless steel structural material. We find that an ITER power plant with a reasonable electric power conversion system would produce no net electric power at its target energy amplification factor of 10. The ARIES-1 conceptual power plant, as conceived, would have an energy amplification of 22 and an electric amplification of 6. If stainless steel were substituted for the SiC composite material assumed, the ARIES-1 electric power amplification would drop to roughly 3. We conclude that practical fusion power plants will likely require a near-ignition operating mode and qualified high temperature materials as prerequisites for commercial viability.

Diversifying Isoprenoid Platforms via Atypical Carbon Substrates and Non-model Microorganisms

Isoprenoid compounds are biologically ubiquitous, and their characteristic modularity has afforded products ranging from pharmaceuticals to biofuels. Isoprenoid production has been largely successful in Escherichia coli and Saccharomyces cerevisiae with metabolic engineering of the mevalonate (MVA) and methylerythritol phosphate (MEP) pathways coupled with the expression of heterologous terpene synthases. Yet conventional microbial chassis pose several major obstacles to successful commercialization including the affordability of sugar substrates at scale, precursor flux limitations, and intermediate feedback-inhibition. Now, recent studies have challenged typical isoprenoid paradigms by expanding the boundaries of terpene biosynthesis and using non-model organisms including those capable of metabolizing atypical C1 substrates. Conversely, investigations of non-model organisms have historically informed optimization in conventional microbes by tuning heterologous gene expression. Here, we review advances in isoprenoid biosynthesis with specific focus on the synergy between model and non-model organisms that may elevate the commercial viability of isoprenoid platforms by addressing the dichotomy between high titer production and inexpensive substrates.

OntoTouTra: Tourist Traceability Ontology Based on Big Data Analytics

Tourist traceability is the analysis of the set of actions, procedures, and technical measures that allows us to identify and record the space–time causality of the tourist’s touring, from the beginning to the end of the chain of the tourist product. Besides, the traceability of tourists has implications for infrastructure, transport, products, marketing, the commercial viability of the industry, and the management of the destination’s social, environmental, and cultural impact. To this end, a tourist traceability system requires a knowledge base for processing elements, such as functions, objects, events, and logical connectors among them. A knowledge base provides us with information on the preparation, planning, and implementation or operation stages. In this regard, unifying tourism terminology in a traceability system is a challenge because we need a central repository that promotes standards for tourists and suppliers in forming a formal body of knowledge representation. Some studies are related to the construction of ontologies in tourism, but none focus on tourist traceability systems. For the above, we propose OntoTouTra, an ontology that uses formal specifications to represent knowledge of tourist traceability systems. This paper outlines the development of the OntoTouTra ontology and how we gathered and processed data from ubiquitous computing using Big Data analysis techniques.

Educational Policy Change, Newspapers and Public Opinion in New Zealand, 1988-1999

<p>This thesis analyses educational trends as reported in five major New Zealand daily newspapers from 1988-1999 when the New Zealand education system underwent radical policy reforms. Newspaper reporting of the educational reforms was set alongside and compared with a range of academic and professional critiques. The role of newspaper reporting differed from the academic literature in two inter-related ways. First, newspapers had to appeal to a ‘reader audience’ so as to achieve their second function, commercial viability. Commercial viability was achieved by a process of ‘gatekeeping’ whereby articles were selected for their publishing suitability. Gatekeeping took into account the reader audience, time constraints and the employer’s political orientation. The key argument of this thesis was, that because of those restraints, reporting on complex educational issues, which required time to investigate, analyse, reflect and theorise, were too difficult and therefore, were largely ignored. A mixed research methodology was used to identify the similarities and differences between academic and professional concerns with those educational articles found in newspapers. Five newspapers were surveyed over 12 years (1988-1999) on the basis of every 11 days, but omitting Sunday. This resulted in 1680 newspapers being identified. Educational articles were coded according to their story content and substory content and scored according to their prominence using the ‘Budd Score’ method. The key findings were that articles about education, in the new global media market with its focus on the commodification of information, were superficial, narrow, unquestioning and given low priority. Such ‘dumbing down’ was seen to have effectively muzzled the ‘watchdog’ role that the media claimed to have upheld. As a result a ‘cultural bricolage’ had led to an unequal power distribution that, based on the evidence of the literature review and the Budd score analysis in this thesis, was arguably anti-social, anti-Maori, anti-feminist, anti-competitive and therefore, anti-democratic.</p>

Educational Policy Change, Newspapers and Public Opinion in New Zealand, 1988-1999

<p>This thesis analyses educational trends as reported in five major New Zealand daily newspapers from 1988-1999 when the New Zealand education system underwent radical policy reforms. Newspaper reporting of the educational reforms was set alongside and compared with a range of academic and professional critiques. The role of newspaper reporting differed from the academic literature in two inter-related ways. First, newspapers had to appeal to a ‘reader audience’ so as to achieve their second function, commercial viability. Commercial viability was achieved by a process of ‘gatekeeping’ whereby articles were selected for their publishing suitability. Gatekeeping took into account the reader audience, time constraints and the employer’s political orientation. The key argument of this thesis was, that because of those restraints, reporting on complex educational issues, which required time to investigate, analyse, reflect and theorise, were too difficult and therefore, were largely ignored. A mixed research methodology was used to identify the similarities and differences between academic and professional concerns with those educational articles found in newspapers. Five newspapers were surveyed over 12 years (1988-1999) on the basis of every 11 days, but omitting Sunday. This resulted in 1680 newspapers being identified. Educational articles were coded according to their story content and substory content and scored according to their prominence using the ‘Budd Score’ method. The key findings were that articles about education, in the new global media market with its focus on the commodification of information, were superficial, narrow, unquestioning and given low priority. Such ‘dumbing down’ was seen to have effectively muzzled the ‘watchdog’ role that the media claimed to have upheld. As a result a ‘cultural bricolage’ had led to an unequal power distribution that, based on the evidence of the literature review and the Budd score analysis in this thesis, was arguably anti-social, anti-Maori, anti-feminist, anti-competitive and therefore, anti-democratic.</p>