Abercrombie Arch Shelter: An excavation near Bathurst, N.S.W.

The article describes the archaeological investigations conducted at the Abercrombie Arch Shelter. The site is a small rockshelter at the base of a large outcrop of altered limestone, the 'Abercrombie Caves Marble'. It is situated in a saddle on top of the 'Grand Arch', a natural tunnel through which passes Grove Creek

The Use of Piezoelectric Actuators in an Energy-Efficient Noise Reduction System

The piezoelectric effect allows for conversion between mechanical stress and electrical impulses. By utilizing this phenomenon, a novel method of sound attenuation was explored and tested in which a piezoelectric plate absorbs part of an incoming sound wave. Reversing the process allows a second plate to produce a phase-inverted wave using the absorbed energy, achieving further reduction through destructive interference

A study on factors affecting the degradation of magnesium and a magnesium-yttrium alloy for biomedical applications.

Controlling degradation of magnesium or its alloys in physiological saline solutions is essential for their potential applications in clinically viable implants. Rapid degradation of magnesium-based materials reduces the mechanical properties of implants prematurely and severely increases alkalinity of the local environment. Therefore, the objective of this study is to investigate the effects of three interactive factors on magnesium degradation, specifically, the addition of yttrium to form a magnesium-yttrium alloy versus pure magnesium, the metallic versus oxide surfaces, and the presence versus absence of physiological salt ions in the immersion solution. In the immersion solution of phosphate buffered saline (PBS), the magnesium-yttrium alloy with metallic surface degraded the slowest, followed by pure magnesium with metallic or oxide surfaces, and the magnesium-yttrium alloy with oxide surface degraded the fastest. However, in deionized (DI) water, the degradation rate showed a different trend. Specifically, pure magnesium with metallic or oxide surfaces degraded the slowest, followed by the magnesium-yttrium alloy with oxide surface, and the magnesium-yttrium alloy with metallic surface degraded the fastest. Interestingly, only magnesium-yttrium alloy with metallic surface degraded slower in PBS than in DI water, while all the other samples degraded faster in PBS than in DI water. Clearly, the results showed that the alloy composition, presence or absence of surface oxide layer, and presence or absence of physiological salt ions in the immersion solution all influenced the degradation rate and mode. Moreover, these three factors showed statistically significant interactions. This study revealed the complex interrelationships among these factors and their respective contributions to degradation for the first time. The results of this study not only improved our understanding of magnesium degradation in physiological environment, but also presented the key factors to consider in order to satisfy the degradation requirements for next-generation biodegradable implants and devices

Mycotoxin Contamination in Grains; Papers presented at the 17th ASEAN Technical Seminar on Grain Postharvest Technology, Lumut, Malaysia, 25-27 July 1995

Crop Production/Industries,

Extending pseudo-Anosov maps to compression bodies

We show that a pseudo-Anosov map on a boundary component of an irreducible 3-manifold has a power that partially extends to the interior if and only if its (un)stable lamination is a projective limit of meridians. The proof is through 3-dimensional hyperbolic geometry, and involves an investigation of algebraic limits of convex cocompact compression bodies.Comment: 29 page

Towards a methodology for rigorous development of generic requirements patterns

We present work in progress on a methodology for the engineering, validation and verification of generic requirements using domain engineering and formal methods. The need to develop a generic requirement set for subsequent system instantiation is complicated by the addition of the high levels of verification demanded by safety-critical domains such as avionics. We consider the failure detection and management function for engine control systems as an application domain where product line engineering is useful. The methodology produces a generic requirement set in our, UML based, formal notation, UML-B. The formal verification both of the generic requirement set, and of a particular application, is achieved via translation to the formal specification language, B, using our U2B and ProB tools

Developing a draft learning progression framework for ESOL in New Zealand schools

Early in 2003 we were commissioned to produce a draft Learning Progression Framework (LPF) for ESOL in the New Zealand curriculum. The draft Framework was completed in June 2003 and entered the consultation round. In producing the draft Framework, we had to address a range of issues. Some these related to user expectations. Others concerned the relationship between the draft Framework and documents such as English in the New Zealand Curriculum, existing curriculum documents relating to other languages, and ESOL frameworks available in other countries. These issues proved to be critical. This paper explores some of these issues and introduces the draft Framework