Canards in advection-reaction-diffusion systems in one spatial dimension

This thesis contains a mathematical investigation of the existence of travelling wave solutions to singularly perturbed advection-reaction-diffusion models of biological processes. An enhanced mathematical understanding of these solutions and models is gained via the identification of canards (special solutions of fast/slow dynamical systems) and their role in the existence of the most biologically relevant, shock-like solutions. The analysis focuses on two existing models. A new proof of existence of a whole family of travelling waves is provided for a model describing malignant tumour invasion, while new solutions are identified for a model describing wound healing angiogenesis.

Fouling of waste heat recovery : numerical and experimental results

Numerical results are presented to investigate the performance of a partly-filled porous heat exchanger for waste heat recovery units. A parametric study was conducted to investigate the effects of inlet velocity and porous block height on the pressure drop of the heat exchanger. The focus of this work is on modelling the interface of a porous and non-porous region. As such, numerical simulation of the problem is conducted along with hot-wire measurements to better understand the physics of the problem. Results from the two sources are then compared to existing theoretical predictions available in the literature which are unable to predict the existence of two separation regions before and after the porous block. More interestingly, a non-uniform interface velocity was observed along the streamwise direction based on both numerical and experimental data.

Do e-learning applications click with students globally? A study of the development and adoption of WriteCite.com

This paper traces the process of invention of adoption of WriteCite.com which is an internet based learning tool used by students to format citation lists. A number of theoretical issues relating to development and deployment of online learning tools are addressed in this paper. A significant finding in this paper is that adoption rate of new technologies amongst students, in this case for WriteCite.com, is not immediately global in nature despite the internet's ubiquity and the existence of internationally accepted bibliographic styles. Rather, and in contrast to neo theories of technology internationalisation, early-stage adoption tends to be geo-centric and concentrated in the US. In the case of WriteCite.com, which has not been sponsored by an academic institution, the findings reflect voluntary rates of globa adoption. From an applied perspective, the process of identifying globally contestable markets is relevant to developers of online learning tools.

Echolocation calls, wing shape, diet and phylogenetic diagnosis of the endemic Chinese bat Myotis pequinius

We describe the echolocation calls, flight morphology and diet of the endemic Chinese bat Myotis pequinius Thomas, 1908. Orientation calls are broadband, and reach low terminal frequencies. Diet comprised 80% beetles by volume. Wing shape and call design suggest that the bats fly in cluttered habitats, and the possession of moderately long ears and the dietary composition imply they forage at least sometimes by gleaning. Myotis pequinius resembles a larger Oriental version of the western Palaearctic species M. nattereri. Phylogenetic analysis based on sequences of the cytochrome b gene of mitochondrial DNA (1,140 base pairs) from a range of Palaearctic Myotis species confirmed that M. pequinius is close to the nattereri group, and is a sister-species to the eastern Palaearctic M. bombinus. One bat sequenced from China could not be identified from available species descriptions. It was smaller than M. pequinius, and also differed from it in sequence divergence by 6.7%, suggesting the existence of additional, cryptic taxonomic diversity in this group. Our phylogenetic analysis also supports the recognition of M. schaubi as a species distinct from M. nattereri in Transcaucasia and south-western Asia. Myotis nattereri tschuliensis is more closely related to M. schaubi than to M. nattereri, and is best considered either as a subspecies of M. schaubi, or possibly as a distinct species.

Explicit finite element modelling of bridge girder bearing pedestals

Bridge girder bearings rest on pedestals to transfer the loading safely to the pier headstock. In spite of the existence of industry guidelines, due to construction complexities, such guidelines are often overlooked. Further, there is paucity of research on the performance of pedestals, although their failure could cause exorbitant maintenance costs. Although reinforced concrete pedestals are recommended in the industry design guidelines, unreinforced concrete and/ or epoxy glue pedestals are provided due to construction issues; such pedestals fail within a very short period of service. With a view to understanding the response of pedestals subject to monotonic loading, a three-dimensional nonlinear explicit finite element micro-model of unreinforced and reinforced concrete pedestals has been developed. Contact and material nonlinearity have been accounted for in the model. It is shown that the unreinforced concrete pedestals suffer from localised edge stress singularities, the failure of which was comparable to those in the field. The reinforced concrete pedestals, on the other hand, distribute the loading without edge stress singularity, again conforming to the field experience.

The effect of the ecstasy 'come-down' on the diagnosis of ecstasy dependence

Background: The existence of an ecstasy dependence syndrome is controversial. We examined whether the acute after-effects of ecstasy use (i.e., the “come-down”) falsely lead to the identification of ecstasy withdrawal and the subsequent diagnosis of ecstasy dependence. Methods: The Structured Clinical Interview for DSM-IV-TR Disorders: Research Version (SCID-RV) was administered to 214 Australian ecstasy users. Ecstasy withdrawal was operationalized in three contrasting ways: (i) as per DSM-IV criteria; (ii) as the expected after effects of ecstasy (a regular come-down); or (iii) as a substantially greater or longer come-down than on first use (intense come-down). These definitions were validated against frequency of ecstasy use, readiness to change and ability to resist the urge to use ecstasy. Confirmatory factor analyses were used to see how they aligned with the overall dependence syndrome. Results: Come-down symptoms increased the prevalence of withdrawal from 1% (DSM-IV criterion) to 11% (intense come-downs) and 75% (regular come-downs). Past year ecstasy dependence remained at 31% when including the DSM-IV withdrawal criteria and was 32% with intense come-downs, but increased to 45% with regular come-downs. Intense come-downs were associated with lower ability to resist ecstasy use and loaded positively on the dependence syndrome. Regular come-downs did not load positively on the ecstasy dependence syndrome and were not related to other indices of dependence. Conclusion: The acute after-effects of ecstasy should be excluded when assessing ecstasy withdrawal as they can lead to a false diagnosis of ecstasy dependence. Worsening of the ecstasy come-down may be a marker for dependence.

Development of a flexible design approach for the deflection zone behind road safety barriers

Flexible design practices broadly permit that design values outside the normal range can be accepted as appropriate for a site-specific context providing that the risk is evaluated and is tolerable. Execution of flexible design demands some evaluation of risk. In restoration projects, it may be the case that an immovable object exists within the zone of the expected deflection of a road safety barrier system. Only by design exception can the situation be determined to be acceptable. However, the notion of using flexible design for road safety barrier design is not well developed. The existence of a diminishing return relationship between safety benefits and provision of increased clear zone has been established previously. This paper proposes that a similar rationale might reasonably apply for the deflection zone behind road safety barriers and describes how the risk associated with road safety barriers might be quantified in order that defensible road safety barrier design can exist below the lower bounds of normal design standards. As such, the methodology described in this paper may provide some basis to enable road authorities to make informed design decisions, particularly for restoration, or “Brownfield”, projects.

Shared values : diverse perspectives – engaging engineering educators in integrating Indigenous engineering knowledge into current curricula

BACKGROUND Engineering is a problem-based practically oriented discipline, whose practitioners aim to find effective solutions to engineering challenges, technically and economically. Engineering educators operate within a mandate to ensure that graduate engineers understand the practicalities and realities of good engineering practice. While this is a vital goal for the discipline, emerging influences are challenging the focus on ‘hard practicalities’ and requiring recognition of the cultural and social aspects of engineering. Expecting graduate engineers to possess communication skills essential for negotiating satisfactory outcomes in contexts of complex social beliefs about the impact of their work can be an unsettling and challenging prospect for engineering educators. This project identifies and addresses Indigenous engineering practices and principles, and their relevance to future engineering practices. PURPOSE This Office of Learning and Teaching (OLT) project proposes that what is known/discoverable about indigenous engineering knowledge and practices must be integrated into engineering curricula. This is an important aspect of ensuring that engineering as a profession responds competently to increasing demands for socially and environmentally responsible activity across all aspects of engineering activity. DESIGN/METHOD The project addresses i) means for appropriate inclusion of Indigenous students into usual teaching activities ii) assuring engineering educators have access to knowledge of Indigenous practices and skills relevant to particular engineering courses and topics iii) means for preparing all students to negotiate their way through issues of indigenous relationships with the land where engineering projects are planned. The project is undertaking wide-ranging research to collate knowledge about indigenous engineering principles and practices and develop relevant resource materials. RESULTS It is common to hear that such social issues as ‘Indigenous concerns’ are only of concern to environmental engineers. We challenge that perspective, and make the case that Indigenous knowledge is an important issue for all engineering educators in relation to effective integration of indigenous students and preparation of all engineering graduates to engage with indigenous communities. At the time of first contact, a rich and varied, technically literate, Indigenous social framework possessed knowledge of the environment that is not yet fully acknowledged in Australian society. A core outcome of the work will be development of resources relating to Indigenous engineering practices for inclusion in engineering core curricula. CONCLUSIONS A large body of technical knowledge was needed to survive and sustain human society in the complex environment that was Australia before 1788. This project is developing resource materials, and supporting documentation, about that knowledge to enable engineering educators to more easily integrate it into current curricula. The project also aims to demonstrate the importance for graduating engineers to appreciate the existence of diverse perspectives on engineering tasks and learn how to value - and employ - multiple paths to possible solutions.

Design democratisation and its understandings through the meaning of the word “design” in Portuguese colonised countries

This paper explores the literature and analyses the different uses and understandings of the word “design” in Portuguese colonised countries, using Brazil as the main example. It investigates the relationship between the linguistic existence of terms to define and describe “design” as an activity and field, and the roles and perceptions of Design by the general society. It also addresses the effects that the lack of a proper translation causes on the local community from a cultural point of view. The current perception of Design in Portuguese colonies is associated to two main aspects: linguistic and historical. Both of them differentiate the countries taken into consideration from other countries that have a different background. The changes associated to the meaning of “design” throughout the years, caused a great impact on the perceptions that people have about Design. On the other hand, the development of Design has also influenced the changes on the meaning of the term, as a result of the legacy from the colonisation period and also as a characteristic of the Portuguese language. Design has developed and reached a level of excellence in Portuguese colonised countries that competes with the most traditional Design cultures in the world. However, this level of Design is enmeshed into an elite belonging to universities and specialised markets, therefore Design is not democratised. The ultimate aim of this study is to promote discussions on how to make the discourse surrounding this area more accessible to people from non-English speaking countries that do not have the word “design” in their local language.

Impact of mobility constraints on epidemic broadcast mechanisms in delay-tolerant networks

In this paper, we investigate the effect of mobility constraints on epidemic broadcast mechanisms in DTNs (Delay-Tolerant Networks). Major factors affecting epidemic broadcast performances are its forwarding algorithm and node mobility. The impact of forwarding algorithm and node mobility on epidemic broadcast mechanisms has been actively studied in the literature, but those studies generally use unconstrained mobility models. The objective of this paper is therefore to quantitatively investigate the effect of mobility constraints on epidemic broadcast mechanisms. We evaluate the performances of three classes of epidemic broadcast mechanisms - P-BCAST (PUSH-based BroadCast), SA-BCAST (Self-Adaptive BroadCast), and HP-BCAST (History-based P-BCAST) - with a random waypoint mobility model with mobility constraints. Our finding includes that the existence of mobility constraints significantly improves the reach ability and dissemination speed of epidemic broadcast mechanisms while degrading their efficiency.

Review of Public Trustee Files - Families and generational asset transfers: Making and challenging wills in contemporary Australia

The Public Trustee file review was designed to address research questions relating to will disputes and socio-cultural and family norms, expectations and obligations that underpin challenges to wills. Findings from this review will augment the earlier review of all adjudicated succession law cases in Australia between January and December 2011. The research team obtained 139 cases for the review. Within the reviewed cases, parties generally needed some kind of formalised assistance to resolve disputes and almost a third ended up going to court. Most claims launched to contest wills were successful i.e. led to a change in distribution. The existence of poor and/or complex personal relationships between beneficiaries, disputants and/or the deceased were a feature of most cases involving will disputes, particularly where disputes were escalated to court. There are significant costs of will contestation both for the estate and the individuals involved in disputes. Previous research has identified that in addition to the direct costs is the indirect cost of extending the time for probate of the will. This review highlights that one of the most significant costs of will contestation is the damage to familial relationships that appears to both drive and be worsened by contestation. Findings of this review highlight the role of Public Trustees in providing financial management and advocacy services to protect and support vulnerable people in the community such as those with impaired capacity, as well as offering services such as will drafting and deceased estate administration.

The David and Goliath principle: Cultural, ideological, and attitudinal underpinnings of the normative protection of low-status groups from criticism

Two studies documented the “David and Goliath” rule—the tendency for people to perceive criticism of “David” groups (groups with low power and status) as less normatively permissible than criticism of “Goliath” groups (groups with high power and status). The authors confirmed the existence of the David and Goliath rule across Western and Chinese cultures (Study 1). However, the rule was endorsed more strongly in Western than in Chinese cultures, an effect mediated by cultural differences in power distance. Study 2 identified the psychological underpinnings of this rule in an Australian sample. Lower social dominance orientation (SDO) was associated with greater endorsement of the rule, an effect mediated through the differential attribution of stereotypes. Specifically, those low in SDO were more likely to attribute traits of warmth and incompetence to David versus Goliath groups, a pattern of stereotypes that was related to the protection of David groups from criticism.

Silylation of mechanically ground kaolinite

Silylated kaolinites were synthesized at 80°C without the use of inert gas protection. The method presented started with mechanical grinding of kaolinite, followed by grafting with 3-aminopropyltriethoxysilane (APTES). The mechanical grinding treatment destroyed the ordered sheets of kaolinite, formed fine fragments and generated broken bonds (undercoordinated metal ions). These broken bonds served as new sites for the condensation with APTES. Fourier transform infrared spectroscopy (FTIR) confirmed the existence of –CH2 from APTES. 29Si cross-polarization magic-angle spinning nuclear magnetic resonance spectroscopy (29Si CP/MAS NMR) showed that the principal bonding mechanism between APTES and kaolinite fitted a tridentate silylation model (T3) with a chemical shift at 66.7 ppm. The silane loadings of the silylated samples were estimated from the mass loss obtained by TG-DTG curves. The results showed that the 6-hour ground kaolinite could be grafted with the most APTES (7.0%) using cyclohexane as solvent. The loaded amount of APTES in the silylated samples obtained in different solvents decreased in the order as: nonpolar solvent > polar solvent with low dielectric constant (toluene) > polar solvent with high dielectric constant (ethanol).

No laughing matter: Blaming the victim of online fraud

There is a strong sense of negativity associated with online fraud victimization. Despite an increasing awareness, understanding about the reality of victimization experiences is not apparent. Rather, victims of online fraud are constructed as greedy and gullible and there is an overwhelming sense of blame and responsibility levelled at them for the actions that led to their losses. This belief transcends both non-victims and victims. The existence of this victim-blaming discourse is significant. Based on interviews with 85 seniors across Queensland, Australia, who received fraudulent emails, this article establishes the victim-blaming discourse as an overwhelmingly powerful and controlling discourse about online fraud victimization. However, the article also examines how humour acts as a tool to reinforce this discourse by isolating victims and impacting on their ability to disclose to those around them. Identifying and challenging this victim-blaming discourse, as well as the role of humour and its social acceptance, is a first step in the facilitation of victim recovery and future well-being.

A vibrational spectroscopic study of tengerite-(Y) Y2(CO3)3 2–3H2O

The mineral tengerite-(Y) has been studied by vibrational spectroscopy. Multiple carbonate stretching modes are observed and support the concept of non-equivalent carbonate units in the tengerite-(Y) structure. Intense sharp bands at 464, 479 and 508 cm−1 are assigned to YO stretching modes. Raman bands at 765 and 775 cm−1 are assigned to the CO32− ν4 bending modes and Raman bands at 589, 611, 674 and 689 cm−1 are assigned to the CO32− ν2 bending modes. Multiple Raman and infrared bands in the OH stretching region are observed, proving the existence of water in different molecular environments in the structure of tengerite-(Y).