Pulse dynamics in a three-component system : stability and bifurcations

In this article, we analyze the stability and the associated bifurcations of several types of pulse solutions in a singularly perturbed three-component reaction-diffusion equation that has its origin as a model for gas discharge dynamics. Due to the richness and complexity of the dynamics generated by this model, it has in recent years become a paradigm model for the study of pulse interactions. A mathematical analysis of pulse interactions is based on detailed information on the existence and stability of isolated pulse solutions. The existence of these isolated pulse solutions is established in previous work. Here, the pulse solutions are studied by an Evans function associated to the linearized stability problem. Evans functions for stability problems in singularly perturbed reaction-diffusion models can be decomposed into a fast and a slow component, and their zeroes can be determined explicitly by the NLEP method. In the context of the present model, we have extended the NLEP method so that it can be applied to multi-pulse and multi-front solutions of singularly perturbed reaction-diffusion equations with more than one slow component. The brunt of this article is devoted to the analysis of the stability characteristics and the bifurcations of the pulse solutions. Our methods enable us to obtain explicit, analytical information on the various types of bifurcations, such as saddle-node bifurcations, Hopf bifurcations in which breathing pulse solutions are created, and bifurcations into travelling pulse solutions, which can be both subcritical and supercritical.

Engineering across cultures : new learning resources for intercultural competency in engineering

BACKGROUND The work described in this paper has emerged from an ALTC/OLT funded project, Exploring Intercultural Competency in Engineering. The project indentified many facets of culture and intercultural competence that go beyond a culture-as-nationality paradigm. It was clear from this work that resources were needed to help engineering educators introduce students to the complex issues of culture as they relate to engineering practice. A set of learning modules focussing on intercultural competence in engineering practice were developed early on in the project. Through the OLT project, these modules have been expanded into a range of resources covering various aspects of culture in engineering. Supporting the resources, an eBook detailing the ins and outs of intercultural competency has also been developed to assist engineering educators to embed opportunities for students to develop skills in unpacking and managing cross-cultural challenges in engineering practice. PURPOSE This paper describes the key principles behind the development of the learning modules, the areas they cover and the eBook developed to support the modules. The paper is intended as an introduction to the approaches and resources and extends an invitation to the community to draw from, and contribute to this initial work. DESIGN/METHOD A key aim of this project was to go beyond the culture-as-nationality approach adopted in much of the work around intercultural competency (Deardorff, 2011). The eBook explores different dimensions of culture such as workplace culture, culture’s influence on engineering design, and culture in the classroom. The authors describe how these connect to industry practice and explore what they mean for engineering education. The packaged learning modules described here have been developed as a matrix of approaches moving from familiar known methods through complicated activities relying to some extent on expert knowledge. Some modules draw on the concept of ‘complex un-order’ as described in the ‘Cynefin domains’ proposed by Kurtz and Snowden (2003). RESULTS Several of the modules included in the eBook have already been trialled at a variety of institutions. Feedback from staff has been reassuringly positive so far. Further trials are planned for second semester 2012, and version 1 of the eBook and learning modules, Engineering Across Cultures, is due to be released in late October 2012. CONCLUSIONS The Engineering Across Cultures eBook and learning modules provide a useful and ready to employ resource to help educators tackle the complex issue of intercultural competency in engineering education. The book is by no means exhaustive, and nor are the modules, they instead provide an accessible, engineering specific guide to bringing cultural issues into the engineering classroom.

An open-source approach to music education through jam2jam XO

This article examines the philosophy and practice of open-source technology in the development of the jam2jam XO software for the One Laptop Per Child (OLPC) computer. It explores how open-source software principles, pragmatist philosophy, improvisation and constructionist epistemologies are operationalized in the design and development of music software, and how such reflection reveals both the strengths and weaknesses of the open-source software development paradigm. An overview of the jam2jam XO platform, its development processes and music educational uses is provided and resulting reflections on the strengths and weaknesses of open-source development for music education are discussed. From an educational and software development perspective, the act of creating open-source software is shown to be a valuable enterprise, however, just because the source code, creative content and experience design are accessible and 'open' to be changed, does not guarantee that educational practices in the use of that software will change. Research around the development and use of jam2jam XO suggests that open-source software development principles can have an impact beyond software development and on to aspects of experience design and learning relationships.

A qualitative study of the determinants of dieting and non-dieting approaches in overweight/obese Australian adults.

Background Dieting has historically been the main behavioural treatment paradigm for overweight/obesity, although a non-dieting paradigm has more recently emerged based on the criticisms of the original dieting approach. There is a dearth of research contrasting why these approaches are adopted. To address this, we conducted a qualitative investigation into the determinants of dieting and non-dieting approaches based on the perspectives and experiences of overweight/obese Australian adults. Methods Grounded theory was used inductively to generate a model of themes contrasting the determinants of dieting and non-dieting approaches based on the perspectives of 21 overweight/obese adults. Data was collected using semi-structured interviews to elicit in-depth individual experiences and perspectives. Results Several categories emerged which distinguished between the adoption of a dieting or non-dieting approach. These categories included the focus of each approach (weight/image or lifestyle/health behaviours); internal or external attributions about dieting failure; attitudes towards established diets, and personal autonomy. Personal autonomy was also influenced by another category; the perceived knowledge and self-efficacy about each approach, with adults more likely to choose an approach they knew more about and were confident in implementing. The time perspective of change (short or long-term) and the perceived identity of the person (fat/dieter or healthy person) also emerged as determinants of dieting or non-dieting approaches respectively. Conclusions The model of determinants elicited from this study assists in understanding why dieting and non-dieting approaches are adopted, from the perspectives and experiences of overweight/obese adults. Understanding this decision-making process can assist clinicians and public health researchers to design and tailor dieting and non-dieting interventions to population subgroups that have preferences and characteristics suitable for each approach.

The record producer as a nexus

This paper considers three fields of interest in the recording process: the performer and the song; the technology of the recording context; and the commercial ambitions of the record company, and positions the record producer as a nexus at the interface of all three. The author reports his structured recollection of several recordings that all achieved substantial commercial success. The processes are considered from the author’s perspective as the record producer, and from inception of the project to completion of the recorded work. What were the processes of engagement? Do the actions reported conform to the template of nexus? This paper proposes that in all recordings the function of producer/nexus is present and necessary—it exists in the interaction of the artistry and the technology¬––and is a useful paradigm for analysis of the recording process.