The Bailey chain and mock theta functions

Standard applications of the Bailey chain preserve mixed mock modularity but not mock modularity. After illustrating this with some examples, we show how to use a change of base in Bailey pairs due to Bressoud, Ismail and Stanton to explicitly construct families of q-hypergeometric multisums which are mock theta functions. We also prove identities involving some of these multisums and certain classical mock theta functions.Comment: 17 pages, to appear in Advances in Mathematic

WARDANDI BOODJA: TRUTH-TELLING

This exegesis is an art and reconciliation response to the Uluru Statement From the Heart. Wardandi Nyungar Elders, Bill, and Nina Webb inform this project of the 1841 Wonnerup/Minninup massacre. Action Research informs the use of Yarning, decolonisation, and collaboration to hear alternative historical narratives. The project culminated in public art and truth-telling workshops to learn and heal together. I ask can art and yarning assist with historical truth-telling and reconciliation

D3-D7 Holographic dual of a perturbed 3D CFT

An appropriately oriented D3-D7-brane system is the holographic dual of relativistic Fermions occupying a 2+1-dimensional defect embedded in 3+1-dimensional spacetime. The Fermions interact via fields of ${\mathcal N}=4$ Yang-Mills theory in the 3+1-dimensional bulk. Recently, using internal flux to stabilize the system in the probe $N_7<<N_3$ limit, a number of solutions which are dual to conformal field theories with Fermion content have been found. We use holographic techniques to study perturbations of a particular one of the conformal field theories by relevant operators. Generally, the response of a conformal field theory to such a perturbation grows and becomes nonperturbative at low energy scales. We shall find that a perturbation which switches on a background magnetic field $B$ and Fermion mass $m$ induces a renormalization group flow that can be studied perturbatively in the limit of small $m^2/B$. We solve the leading order explicitly. We find that, for one particular value of internal flux, the system exhibits magnetic catalysis, the spontaneous breaking of chiral symmetry enhanced by the presence of the magnetic field. In the process, we derive formulae predicting the Debye screening length of the Fermion-antiFermion plasma at finite density and the diamagnetic moment of the ground state of the Fermion system in the presence of a magnetic field.Comment: 23 pages, two figures; typos corrected, some comments adde

Hecke-type double sums, Appell-Lerch sums, and mock theta functions (I)

By developing a connection between partial theta functions and Appell-Lerch sums, we find and prove a formula which expresses Hecke-type double sums in terms of Appell-Lerch sums and theta functions. Not only does our formula prove classical Hecke-type double sum identities such as those found in work Kac and Peterson on affine Lie Algebras and Hecke modular forms, but once we have the Hecke-type forms for Ramanujan's mock theta functions our formula gives straightforward proofs of many of the classical mock theta function identities. In particular, we obtain a new proof of the mock theta conjectures. Our formula also applies to positive-level string functions associated with admissable representations of the affine Lie Algebra $A_1^{(1)}$ as introduced by Kac and Wakimoto

Oil quality in diesel engines with on line oil cleaning using a heated lubricating oil recycler

A method of cleaning the oil on line was investigatedusing a bypass fine particulate filter followed by an infra red heater to remove water and light diesel fractions in the oil. This was tested on a range of on road vehicles and a Ford 1.8 litre IDI passenger car engine on a test bed. Comparison was made with the oil quality on the same vehicles and engines without the on-line recycler. Test times were from 200 to 1500 hours of oil ageing and some of the tests showed that the oil quality was still good after 4 times the normal oil life. The results showed that the on line oil recycler cleaning system reduced the rate of fall of the TBN and rate of increase of the TAN. There was a very significant reduction in the soot in oil and the fuel dilution. There was also a consistent reduction in all the wear metals apart from copper and a decrease in the rate of reduction of oil additives. There was also measured on the Ford IDI engine a 5% reduced fuel consumption. Many of these effects were attributed to an influence of the cleaner oil on reduced engine deposits

Oil quality in diesel engines with on line oil cleaning using a heated lubricating oil recycler

A method of cleaning the oil on line was investigatedusing a bypass fine particulate filter followed by an infra red heater to remove water and light diesel fractions in the oil. This was tested on a range of on road vehicles and a Ford 1.8 litre IDI passenger car engine on a test bed. Comparison was made with the oil quality on the same vehicles and engines without the on-line recycler. Test times were from 200 to 1500 hours of oil ageing and some of the tests showed that the oil quality was still good after 4 times the normal oil life. The results showed that the on line oil recycler cleaning system reduced the rate of fall of the TBN and rate of increase of the TAN. There was a very significant reduction in the soot in oil and the fuel dilution. There was also a consistent reduction in all the wear metals apart from copper and a decrease in the rate of reduction of oil additives. There was also measured on the Ford IDI engine a 5% reduced fuel consumption. Many of these effects were attributed to an influence of the cleaner oil on reduced engine deposits

Application of a portable FTIR for measuring on-road emissions

The objective of this work was the development of an onroad in-vehicle emissions measurement technique utilizing a relatively new, commercial, portable Fourier Transform Infra-Red (FTIR) Spectrometer capable of identifying and measuring (at approximately 3 second intervals) up to 51 different compounds. The FTIR was installed in a medium class EURO1 spark ignition passenger vehicle in order to measure on-road emissions. The vehicle was also instrumented to allow the logging of engine speed, road speed, global position, throttle position, air-fuel ratio, air flow and fuel flow in addition to engine, exhaust and catalyst temperatures. This instrumentation allowed the calculation of massbased emissions from the volume-based concentrations measured by the FTIR. To validate the FTIR data, the instrument was used to measure emissions from an engine subjected to a real-world drive cycle using an AC dynamometer. Standard analyzers were operated simultaneously for comparison with the FTIR and the standard analyzer results showed that most pollutants (NOx, CO2, CO) were within ~10% of a standard analyzer during steady state conditions and within 20% during transients. The exception to this was total HC which was generally 50% or less than actual total HC, but this was due to the limited number of hydrocarbons measured by the FTIR. In addition to the regulated emissions, five toxic hydrocarbon species were analyzed and found to be sensitive to cold starts in varying proportions. Finally, FTIR data was compared to results from a commercially available on-road measurement system (Horiba OBS- 1000), and there was good agreement

The effect of ambient temperature on cold start urban traffic emissions for a real world SI car

The influence of ambient temperature on exhaust emissions for an instrumented Euro 1 SI car was determined. A real world test cycle was used, based on an urban drive cycle that was similar to the ECE urban drive cycle. It was based on four laps of a street circuit and an emissions sample bag was taken for each lap. The bag for the first lap was for the cold start emissions. An in-vehicle direct exhaust dual bag sampling technique was used to simultaneously collect exhaust samples upstream and downstream of the three-way catalyst (TWC). The cold start tests were conducted over a year, with ambient temperatures ranging from – 2°C to 32°C. The exhaust system was instrumented with thermocouples so that the catalyst light off temperature could be determined. The results showed that CO emissions for the cold start were reduced by a factor of 8 downstream of catalyst when ambient temperature rose from -2°C to 32°C, the corresponding hydrocarbon emissions were reduced by a factor of 4. There was no clear relationship between NOx emissions and ambient temperature. For subsequent laps of the test circuit the reduction of CO and HC emissions as a function of ambient temperature was lower. The time for catalyst light off increased by 50% as the ambient temperature was reduced. The results show that the vehicle used is unlikely to meet the new – 7oC cold start CO emission regulations

What is 'binge drinking'? Perceptions of Australian adolescents and adults, and implications for mass media campaigns

Objective: While the term ‘binge drinking’ has no definitive definition, it is commonly used in lay conversation and mass media communication campaigns. It is important to understand how the general population interprets the term, and their positive and negative perceptions of this behaviour. Methods: A convenience sample of 549 participants from two Australian towns completed a survey on perceptions of binge drinking; 221 adolescents, 104 parents of adolescents and 224 adult community members. Results: Across all three groups, binge drinking was defined using broad descriptors; few respondents referred to specific consumption levels and those who did varied widely in the quantities specified. The majority of respondents described binge drinking negatively and, in most cases, more negatively for adolescents than adults. However, both adult groups perceived binge drinking to be more enjoyable and pleasant for adolescents than for adults, and more enjoyable and pleasant than adolescents did themselves. Conclusions and Implications: There is a need for shared understanding of terms to ensure that educational interventions and communication campaigns are using the same definitions as their target audiences. There is also a need to ensure adults are not providing young people with mixed messages about excessive alcohol consumption