Implementing Shared Memory on Mesh-Connected Computers and on the Fat-Tree

We present deterministic upper and lower bounds on the slowdown required to simulate an (n, m)-PRAM on a variety of networks. The upper bounds are based on a novel scheme that exploits the splitting and combining of messages. This scheme can be implemented on an n-node d-dimensional mesh (for constant d) and on an n-leaf pruned butterfly and attains the smallest worst-case slowdown to date for such interconnections, namely, O(n^1/d(log(m/n))^1-1/d) for the d-dimensional mesh (with constant d) and O( ) for the pruned butterfly. In fact, the simulation on the pruned butterfly is the first PRAM simulation scheme on an area-universal network. Finally, we prove restricted and unrestricted lower bounds on the slowdown of any deterministic PRAM simulation on an arbitrary network, formulated in terms of the bandwidth properties of the interconnection as expressed by its decomposition tree.     

Experiences of creating four video library collections with the Físchlár system

This paper describes how the Físchlár system, which supports indexing, browsing and searching through archives of digital video information, has been used to create four separate video libraries of information. We briefly introduce Físchlár and then describe its application in Físchlár-TV (a digital library of recorded broadcast TV content, updated regularly), Físchlár-News (a digital library of TV news, updated daily), and Físchlár-Nursing (a digital library of video teaching materials in the domain of nursing), and how Físchlár has also been used to provide searching through a collection as part of the TREC2002 video track interactive user experiments. Our experiences show that the range of user requirements for accessing video content seems to be much broader than for any other media, which makes the development of video access techniques very challenging.     

Tight Bounds on Parallel List Marking

The list marking problem involves marking the nodes of an ℓ-node linked list stored in the memory of a (p, n)-PRAM, when only the position of the head of the list is initially known, while the remaining list nodes are stored in arbitrary memory locations. Under the assumption that cells containing list nodes bear no distinctive tags distinguishing them from other cells, we establish anΩ(min{ℓ, n/p}) randomized lower bound for ℓ-node lists and present a deterministic algorithm whose running time is within a logarithmic additive term of this bound. Such a result implies that randomization cannot be exploited in any significant way in this setting. For the case where list cells are tagged in a way that differentiates them from other cells, the above lower bound still applies to deterministic algorithms, while we establish a tight

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bound for randomized algorithms. Therefore, in the latter case, randomization yields a better performance for a wide range of parameter values.     

Liquid bridge instability applied to microfluidics

This paper presents a new way of combining and mixing reagents within one droplet, which may then be used as a microfluidic biochemical reactor. This is made possible by coalescing aqueous droplets on opposing microcapillary tips immersed in density-matched silicone oil. It was found that there are two possible outcomes from a binary capillary-suspended droplet interaction. The droplets may coalesce to form a stable fluid bridge between opposing capillary tips. The droplets may, however, coalesce to form an unstable liquid bridge that quickly ruptures resulting in the two fluid volumes combining into one droplet suspended from a single capillary tip. The stability boundary that determines one outcome or the other was found to be related to a number of variables that describe the equilibrium shape of the liquid bridge interface. Suspending the host droplet from a larger diameter microcapillary dramatically increases the range of volumes that the system can combine by shifting the stability boundary. This ensures the desired effect of pinch-off near the tip of the finer microcapillary thereby dispensing microfluidic samples in one direction.     

A parallel-plate flow chamber to study initial cell adhesion on a nanofeatured surface

Cells in the human body come across many types of information, which they respond to. Both material chemistry and topography of the surface where they adhere have an effect on cell shape, proliferation, migration, and gene expression. It is possible to create surfaces with topography at the nanometric scale to allow observation of cell-topography interactions. Previous work has shown that 100-nm-diameter pits on a 300-nm pitch can have a marked effect in reducing the adhesion of rat fibroblasts in static cultures. In the present study, a flow of cell suspension was used to investigate cell adhesion onto nanopits in dynamic conditions, by means of a parallel-plate flow chamber. A flow chamber with inner nanotopography has been designed, which allows real-time observation of the flow over the nanopits. A nanopitted pattern was successfully embossed into polymethylmethacrylate to meet the required shape of the chamber. Dynamic cell adhesion after 1 h has been quantified and compared on flat and nanopitted polymethylmethacrylate substrates. The nanopits were seen to be significantly less adhesive than the flat substrates (p<0.001), which is coherent with previous observations of static cultures.     

A Circular Economy Model of Economic Growth with Circular and Cumulative Causation and Trade

Networks and Spatial Economics - The idea of a circular economy, first discussed by Kenneth Boulding in the 1960s and ‘70&nbsp;s and reintroduced by environmental economists David Pearce...     

A readout for large arrays of microwave kinetic inductance detectors

Microwave kinetic inductance detectors (MKIDs) are superconducting detectors capable of counting single photons and measuring their energy in the UV, optical, and near-IR. MKIDs feature intrinsic frequency domain multiplexing (FDM) at microwave frequencies, allowing the construction and readout of large arrays. Due to the microwave FDM, MKIDs do not require the complex cryogenic multiplexing electronics used for similar detectors, such as transition edge sensors, but instead transfer this complexity to room temperature electronics where they present a formidable signal processing challenge. In this paper, we describe the first successful effort to build a readout for a photon counting optical/near-IR astronomical instrument, the ARray Camera for Optical to Near-infrared Spectrophotometry. This readout is based on open source hardware developed by the Collaboration for Astronomy Signal Processing and Electronics Research. Designed principally for radio telescope backends, it is flexible enough to be used for a variety of signal processing applications.     

Contemporary project portfolio management: Reflections on the development of an Australian Competency Standard for Project Portfolio Management

Project portfolio management is an emerging aspect of business management that focuses on how projects are selected, prioritised, integrated, managed and controlled in the multi-project context that exists in modern organisations. Competency standards have been developed by professional bodies for project managers. However, to date there has been no attempt to develop a competency standard at the portfolio management level. This paper examines the process for development of the first performance-based competency standard for project portfolio management and identifies how this contributes to the body of knowledge in both project portfolio management and project management more broadly. The intent is to use the Standard to improve project portfolio management capability and practice in organisations, which in turn promotes efficient resource use and more profitable project outcomes. Specific issues regarding Australian practice are described, along with implications for how this may impact Australian practice in the future.     

R-Matrix Theory for Nanoscale Phonon Thermal Transport across Devices and Interfaces

We have adapted R-matrix theory to calculate phonon scattering across systems of molecular to mesoscopic scale. The key novelty of this work is that the only required information about the scattering region is its normal modes, which are evaluated only once for a system. Thus, R-matrix theory is a computationally efficient and simple approach to calculate phonon scattering in larger systems. To validate and to demonstrate the applicability of the theory, we apply it to two systems: a one-dimensional chain of atoms and a graphene nanoribbon. In both cases, we discuss the effect of mass impurities on thermal transport.