Detection and Characterisation of Combustion Formed Nanoparticles Using Time-Resolved Laser-Induced Emission

This thesis provides an improved characterisation of the evolution of soot nanoparticles in laminar and turbulent flames with a particular focus on the transition from nucleation to solid particles where intermediate structures occur. Laser light at 266 nm is primarily used for Laser-Induced Fluorescence (LIF) measurements as a means to detect and characterise incipient soot nanostructures that retain molecular qualities. These species have a size in the order of a few nanometres and do not absorb light at longer visible and infrared (IR) wavelengths. In addition, the 266 nm laser is used for Elastic Light Scattering and Laser-Induced Incandescence that prevail where larger solid particles are present. A 1064 nm laser, on the other hand, is used to exclusively excite solid soot particles that do absorb in the IR and preferentially incandesce. The combination of these Laser-induced-Emissions (LIE) is used to track the presence and character of both soot and soot precursor nanostructures. A key feature of these measurements is the ability to track the temporal decay of LIEs. Measurements taken in different combustion conditions (premixed, diffusion and turbulent) highlight different behaviours and properties of combustion formed particles. In all cases, the decay time of the majority of LIF signals is found to be much longer than that expected for molecules present with these flames at the same temperature, yet much shorter and spectrally different than that of soot particles, as is expected from semi-rigid structures. In some cases an obvious transition from smaller aromatic species to larger more rigid nanostructures is inferred from redshifted spectra downstream and longer fluorescent decay times. Collectively, these findings confirm the hybrid nature of nanostructures (semi-solid structure retaining molecular qualities) that dominate the early evolution of soot and highlight the multiple pathways in which soot precursor nanostructures initiate and evolve

On Artin's primitive root conjecture

Artins Vermutung über Primitivwurzeln besagt, dass es zu jeder ganzen Zahl a, die weder 0, ±1 noch eine Quadratzahl ist, unendlich viele Primzahlen p gibt, sodass a eine Primitivwurzel modulo p ist, d.h. a erzeugt eine multiplikative Untergruppe von Q*, dessen Reduktion modulo p Index 1 in (Z/pZ)* hat. Dies wirft die Frage nach Verteilung von Index und Ordnung dieser Reduktion in (Z/pZ)* auf, wenn man p variiert. Diese Arbeit widmet sich verallgemeinerten Fragestellungen in Zahlkörpern: Ist K ein Zahlkörper und Gamma eine endlich erzeugte unendliche Untergruppe von K*, so werden Momente von Index und Ordnung der Reduktion von Gamma sowohl modulo bestimmter Familien von Primidealen von K als auch modulo aller Ideale von K untersucht. Ist Gamma die Gruppe der Einheiten von K, so steht diese Fragestellung in engem Zusammenhang mit der Ramanujan Vermutung in Zahlkörpern. Des Weiteren werden analoge Probleme für rationale elliptische Kurven E betrachtet: Bezeichnet Gamma die von einem rationalen Punkt von E erzeugte Gruppe, so wird untersucht, wie sich Index und Ordnung der Reduktion von Gamma modulo Primzahlen verhalten. Teilweise unter Voraussetzung gängiger zahlentheoretischer Vermutungen werden jeweils asymptotische Formeln in manchen Fällen bewiesen und generelle Schwierigkeiten geschildert, die solche in anderen Fällen verhindern. Darüber hinaus wird eine weitere verwandte Fragestellung betrachtet und bewiesen, dass zu jeder hinreichend großen Primzahl p stets eine Primitivwurzel modulo p existiert, die sich als Summe von zwei Quadraten darstellen lässt und nach oben im Wesentlichen durch die Quadratwurzel von p beschränkt ist

Subtropical Subdivisions: Toward a Lot-rating Methodology for Subtropical Climates

What role can climatically appropriate subdivision design play in decreasing the use of energy required to cool premises by maximising access to natural ventilation? How can this design be achieved? The subdivision design stage is critical to urban and suburban sustainability outcomes, as significant changes after development are constrained by the configuration of the subdivision, and then by the construction of the dwellings. Existing Australian lot rating methodologies for energy efficiency, such as that by the Sustainable Energy Development Authority (SEDA), focus on reducing heating needs by increasing solar access, a key need in Australia’s temperate zone. A recent CRC CI project, Sustainable Subdivisions: Energy (Miller and Ambrose 2005) examined these guidelines to see if they could be adapted for use in subtropical South East Queensland (SEQ). Correlating the lot ratings with dwelling ratings, the project found that the SEDA guidelines would need to be modified for use to make allowance for natural ventilation. In SEQ, solar access for heating is less important than access to natural ventilation, and there is a need to reduce energy used to cool dwellings. In Queensland, the incidence of residential air-conditioning was predicted to reach 50 per cent by the end of 2005 (Mickel 2004). The CRC-CI, Sustainable Subdivisions: Ventilation Project (CRC-CI, in progress), aims to verify and quantify the role natural ventilation has in cooling residences in subtropical climates and develop a lot rating methodology for SEQ. This paper reviews results from an industry workshop that explored the current attitudes and methodologies used by a range of professionals involved in subdivision design and development in SEQ. Analysis of the workshop reveals that a key challenge for sustainability is that land development in subtropical SEQ is commonly a separate process from house design and siting. Finally, the paper highlights some of the issues that regulators and industry face in adopting a lot rating methodology for subdivisions offering improved ventilation access, including continuing disagreement between professionals over the desirability of rating tools

Critical Discourse Analysis of Obasanjo’s Letter ‘Before Is Too Late’ to Jonathan

This paper asserts that language has a close link with politics and is not merely a mode of actions but a means of interaction. Language cannot make sense on its own if not well constructed and channeled. The basic for mutual understanding and communication among interlocutors is hinged on the way and manner language is expressed. The letter coming against the obvious disagreements between the two personae’s, the paper takes a critical discourse analysis of former president Olusegun Obasanjo letter to President Goodluck Jonathan. We conclude that the author used a lot of power and superiority, metaphorical extensions, Linguistic irony, pun and Face Threatening Act to convey the tone of the letter

Learning company for sustainable competitiveness: Towards a model and theory development

Previous studies on learning organizations do not provide a strategic framework of adapting organizational learning for sustainable competitiveness. This paper reviews various contributions on developing learning companies with an objective of proposing ideal management practices for sustainable competitiveness. Based on existing literature review, the essence of integrating business strategy with learning which helps the organization realize sustainable competitiveness. The paper holds that managers need to identify learner’s needs and provide conducive learning opportunities and nurture knowledge sharing as part of organizational culture. Further, existing incentives should enhance the desire to learn, as well as developing appropriate mechanisms, leadership and management approaches. The paper adopts the systems approach to exhibit how organizational learning may be adapted within organizational settings. Based on existing theories and previous discussions, the paper seeks to show how organizational learning may be modeled and implemented in developing countries within large and small firms in the 21st century. In conclusions drawn and recommendations for further research emphasis is laid on the need to link organizational learning to performance as a grey area to be explored

Conceptual fusion of the logical framework approach and outcome mapping

This paper describes the rational for and the process of creating a fusion model incorporating OM and LFA. This is the output of an OMLC funded small-scale research grant

Subtropical subdivisions : toward a lot-rating methodology for subtropical climates

What role can climatically appropriate subdivision design play in decreasing the use of energy required to cool premises by maximising access to natural ventilation? How can this design be achieved? The subdivision design stage is critical to urban and suburban sustainability outcomes, as significant changes after development are constrained by the configuration of the subdivision, and then by the construction of the dwellings. Existing Australian lot rating methodologies for energy efficiency, such as that by the Sustainable Energy Development Authority (SEDA), focus on reducing heating needs by increasing solar access, a key need in Australia’s temperate zone. A recent CRC CI project, Sustainable Subdivisions: Energy (Miller and Ambrose 2005) examined these guidelines to see if they could be adapted for use in subtropical South East Queensland (SEQ). Correlating the lot ratings with dwelling ratings, the project found that the SEDA guidelines would need to be modified for use to make allowance for natural ventilation. In SEQ, solar access for heating is less important than access to natural ventilation, and there is a need to reduce energy used to cool dwellings. In Queensland, the incidence of residential air-conditioning was predicted to reach 50 per cent by the end of 2005 (Mickel 2004). The CRC-CI, Sustainable Subdivisions: Ventilation Project (CRC-CI, in progress), aims to verify and quantify the role natural ventilation has in cooling residences in subtropical climates and develop a lot rating methodology for SEQ. This paper reviews results from an industry workshop that explored the current attitudes and methodologies used by a range of professionals involved in subdivision design and development in SEQ. Analysis of the workshop reveals that a key challenge for sustainability is that land development in subtropical SEQ is commonly a separate process from house design and siting. Finally, the paper highlights some of the issues that regulators and industry face in adopting a lot rating methodology for subdivisions offering improved ventilation access, including continuing disagreement between professionals over the desirability of rating tools

Development of an Explainable Artificial Intelligence Prototype for Interpreting Predictive Models

Artificial Intelligence (AI) now depends on black box machine learning (ML) models which lack algorithmic transparency. Some governments are responding to this through legislation like the “Right of Explanation” rule in the EU and “Algorithmic Accountability Act” in the USA in 2019. The attempt to open up the black box and introduce some level of interpretation has given rise to what is today known as Explainable Artificial Intelligence (XAI). The objective of this paper is to provide a design and implementation of an Explainable Artificial Intelligence Prototype (ExplainEx) that interprets predictive models by explaining their confusion matrix, component classes and classification accuracy. This study is limited to four ML algorithms including J48, Random Tree, RepTree and FURIA. At the core of the software is an engine automating a seamless interaction between Expliclas Web API and the trained datasets, to provide natural language explanation. The prototype is both a stand-alone and client-server based system capable of providing global explanations for any model built on any of the four ML algorithms. It supports multiple concurrent users in a client-server environment and can apply all four algorithms concurrently on a single dataset and returning both precision score and explanation. It is a ready tool for researchers who have datasets and classifiers prepared for explanation. This work bridges the gap between prediction and explanation, thereby allowing researchers to concentrate on data analysis and building state-of-the-art predictive models

Case Management of Severe Malaria - A Forgotten Practice: Experiences from Health Facilities in Uganda

INTRODUCTION: Severe malaria is a life-threatening medical emergency and requires prompt and effective treatment to prevent death. There is paucity of published information on current practices of severe malaria case management in sub-Saharan Africa; we evaluated the management practices for severe malaria in Ugandan health facilities METHODS AND FINDINGS: We did a cross sectional survey, using multi-stage sampling methods, of health facilities in 11 districts in the eastern and mid-western parts of Uganda. The study instruments were adapted from the WHO hospital care assessment tools. Between June and August 2009, 105 health facilities were surveyed and 181 health workers and 868 patients/caretakers interviewed. None of the inpatient facilities had all seven components of a basic care package for the management of severe malaria consistently available during the 3 months prior to the survey. Referral practices were appropriate for <10% (18/196) of the patients. Prompt care at any health facility was reported by 29% (247/868) of patients. Severe malaria was correctly diagnosed in 27% of patients (233).Though the quinine dose and regimen was correct in the majority (611/868, 70.4%) of patients, it was administered in the correct volumes of 5% dextrose in only 18% (147/815). Most patients (80.1%) had several doses of quinine administered in one single 500 ml bottle of 5% dextrose. Medications were purchased by 385 (44%) patients and medical supplies by 478 patients (70.6%). CONCLUSIONS: Management of severe malaria in Ugandan health facilities was sub-optimal. These findings highlight the challenges of correctly managing severe malaria in resource limited settings. Priority areas for improvement include triage and emergency care, referral practises, quality of diagnosis and treatment, availability of medicines and supplies, training and support supervision