On acoustic propagation in three-dimensional rectangular ducts with flexible walls and porous linings

This is the post-print version of the Article. The official published version can be accessed from the links below - Copyright @ 2012 Acoustical Society of AmericaThe focus of this article is toward the development of hybrid analytic-numerical mode-matching methods for model problems involving three-dimensional ducts of rectangular cross-section and with flexible walls. Such methods require first closed form analytic expressions for the natural fluid-structure coupled waveforms that propagate in each duct section and second the corresponding orthogonality relations. It is demonstrated how recent theory [Lawrie, Proc. R. Soc. London, Ser. A 465, 2347–2367 (2009)] may be extended to a wide class of three-dimensional ducts, for example, those with a flexible wall and a porous lining (modeled as an equivalent fluid) or those with a flexible internal structure, such as a membrane (the “drum-like” silencer). Two equivalent expressions for the eigenmodes of a given duct can be formulated. For the ducts considered herein, the first ansatz is dependent on the eigenvalues/eigenfunctions appropriate for wave propagation in the corresponding two-dimensional flexible-walled duct, whereas the second takes the form of a Fourier series. The latter offers two advantages: no “root-finding” is involved and the method is appropriate for ducts in which the flexible wall is orthotropic. The first ansatz, however, provides important information about the orthogonality properties of the three-dimensional eigenmodes

A surgical re-tread

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A Systemic Approach to Building Resilience at Work: Exploring the Resilience of Individuals, Leaders, and Teams

This item is only available electronically.There is growing interest amongst practitioners and managers regarding strategies to increase resilience in the workplace. While the occurrence of resilience programs has been increasing over the past decade, research on measuring and conceptualising resilience is only in its infancy (Bardoel, Pettit, De Cieri & McMillan, 2014). A sound understanding of the current measures used to assess resilience within the workplace domain will help to inform approaches to building resilience with individuals and teams. Accordingly, a narrative review including 25 peer-reviewed articles explored how resilience is currently conceptualised and measured, and identified improvements that could be made to ensure organisations have access to valid and practical resilience tools. A range of issues are discussed and recommendations are made to improve the conceptualisation of resilience, selection of measurement tools, and areas requiring further exploration. Overall, this review serves as a resource to inform practitioners of the best available resilience measures to capture an organisations’ current capacity for resilience, or measure the efficacy of resilience training. Additionally, information on issues requiring further research is provided for scholars who are attempting to advance this line of inquiry.Thesis (M.Psych(Organisational & Human Factors)) -- University of Adelaide, School of Psychology, 201

Tricritical point in strongly coupled U(1) gauge theory with fermions and scalars

We investigate the tricritical point in the lattice fermion--gauge--scalar model with U(1) gauge symmetry. In the vicinity of this point, in the phase with the broken chiral symmetry, we observe the scaling behavior of the chiral condensate and of the masses of composite fermion and composite scalar, indicating the existence of an interesting continuum limit of the model at this point.Comment: Contribution to Lattice 95, LaTeX file (4 pages), 5 ps-figures appended (uuencoded

Crossover from the parity-conserving pair contact process with diffusion to other universality classes

The pair contact process with diffusion (PCPD) with modulo 2 conservation (\pcpdt) [$2A\to 4A$, $2A\to 0$] is studied in one dimension, focused on the crossover to other well established universality classes: the directed Ising (DI) and the directed percolation (DP). First, we show that the \pcpdt shares the critical behaviors with the PCPD, both with and without directional bias. Second, the crossover from the \pcpdt to the DI is studied by including a parity-conserving single-particle process ($A \to 3A$). We find the crossover exponent $1/\phi_1 = 0.57(3)$, which is argued to be identical to that of the PCPD-to-DP crossover by adding $A \to 2A$. This suggests that the PCPD universality class has a well defined fixed point distinct from the DP. Third, we study the crossover from a hybrid-type reaction-diffusion process belonging to the DP [$3A\to 5A$, $2A\to 0$] to the DI by adding $A \to 3A$. We find $1/\phi_2 = 0.73(4)$ for the DP-to-DI crossover. The inequality of $\phi_1$ and $\phi_2$ further supports the non-DP nature of the PCPD scaling. Finally, we introduce a symmetry-breaking field in the dual spin language to study the crossover from the \pcpdt to the DP. We find $1/\phi_3 = 1.23(10)$, which is associated with a new independent route from the PCPD to the DP.Comment: 8 pages, 8 figure