Maintaining New Zealand’s electrical reserve management tool

Managing the electrical reserves in a small, geographically elongated nation like New Zealand is a challenge. The Reserve Management Tool (RMT) developed over a decade ago optimally schedules the reserve load given the current and anticipated circumstances every half hour to ensure that the reserve requirement for electricity is always met. However with changes in the underlying computing platform, and the recognition that the tool needed to be more flexible to incorporate future generator development meant that this tool needed a revamp. This paper describes the present tool, the motivation for the redesign and demonstrates the new capabilities

A kinetic model of municipal sludge degradation during non-catalytic wet oxidation

Wet oxidation is a successful process for the treatment of municipal sludge. In addition, the resulting effluent from wet oxidation is a useful carbon source for subsequent biological nutrient removal processes in wastewater treatment. Owing to limitations with current kinetic models, this study produced a kinetic model which predicts the concentrations of key intermediate components during wet oxidation. The model was regressed from lab-scale experiments and then subsequently validated using data from a wet oxidation pilot plant. The model was shown to be accurate in predicting the concentrations of each component, and produced good results when applied to a plant 500 times larger in size. A statistical study was undertaken to investigate the validity of the regressed model parameters. Finally the usefulness of the model was demonstrated by suggesting optimum operating conditions such that volatile fatty acids were maximised

The Significance of Powder Breakdown During Conveying Within Industrial Milk Powder Plants

Instant whole milk powder (IWMP) is designed to rapidly dissolve in water, which depends on the particle size distribution (PSD). The fragile milk powder exiting the dryer has to be conveyed for packing, which can break down the particles, worsening the dissolution properties. This work investigated the importance of in-plant conveying in determining the nal functional properties at the industrial scale. IWMP breakdown was compared between two plants with di erent transport systems; a pneumatic system and bucket elevator. It was expected that the plant with the bucket elevator consistently produced powder with superior dissolution due to lower breakdown during transport. This was evaluated using the change in PSD. It was found that both plants had a similar decrease in the median particle size, and powder with an initially larger particle size showed more breakdown. However, it was not enough to compensate for the initially larger size. Thus powder that started out larger still had a larger particle size after transport. When quanti ed using the change in bulk density, a low initial bulk density compensated for large breakdown during conveying and ameliorated the impact on the functional properties. Thus in order to produce IWMP with the desired functionalities the focus should be on improving the initial agglomeration, as oppose to reducing transport breakdown.

Auto-code generation for fast embedded model predictive controllers

The implementation of model predictive controllers on low-cast hardware such as micro-controllers has been traditionally hampered by the high computing and associated memory demands of the algorithm. This paper describes a completely automatic way to implement an MPC controller on embedded hardware starting from a dynamic model in \ml. The resultant controller runs stand-alone on the embedded hardware, is extremely fast, exhibits a modest memory footprint and best of all, requires no particular embedded programming experience from the user

Making sense of marriage: Gender and the transition to adulthood in Nairobi, Kenya

Objective: The objective of this study was to examine how young people in Nairobi, Kenya, are making sense of marriage, both in terms of their own lives and its social significance. Background: In many sub‐Saharan African communities, marriage has been a fundamental marker of the transition to adulthood. However, union formation is changing, particularly in urban areas—partnering is occurring later and nonmarital cohabitation is increasingly common with the pathways to union formation differing by gender. Young people\u27s perspectives on marriage are valuable for a deeper understanding of these trends. Method: A total of 74 in‐depth interviews with youth living in the slums of Nairobi, Kenya, were qualitatively analyzed with particular attention to personal and normative understandings of marriage along with how they vary by gender. Results: Marriage emerged as an important part of most respondents\u27 life projects, whether or not they considered it key to socially recognized adulthood. Attitudes differed by gender, with young women\u27s greater ambivalence and aversion toward marriage, particularly early marriage, contrasting with young men\u27s frustrated desire for marriage amidst economic constraints. Young men\u27s main worry about marriage was not being able to support a family, whereas young women were often concerned that marrying would thwart their aspirations regarding education and work. Conclusion: Marriage continues to be a significant social marker of adulthood despite a shifting demographic reality. Differences in young people\u27s attitudes are related to gendered concerns around marriage and economic independence