Parallelization of the discrete gradient method of non-smooth optimization and its applications

We investigate parallelization and performance of the discrete gradient method of nonsmooth optimization. This derivative free method is shown to be an effective optimization tool, able to skip many shallow local minima of nonconvex nondifferentiable objective functions. Although this is a sequential iterative method, we were able to parallelize critical steps of the algorithm, and this lead to a significant improvement in performance on multiprocessor computer clusters. We applied this method to a difficult polyatomic clusters problem in computational chemistry, and found this method to outperform other algorithms.

A new method for locating the global optimum : application of the cutting angle method to molecular structure prediction

Many problems in chemistry depend on the ability to identify the global minimum or maximum of a function. Examples include applications in chemometrics, optimization of reaction or operating conditions, and non-linear least-squares analysis. This paper presents the results of the application of a new method of deterministic global optimization, called the cutting angle method (CAM), as applied to the prediction of molecular geometries. CAM is shown to be competitive with other global optimization techniques for several benchmark molecular conformation problem. CAM is a general method that can also be applied to other computational problems involving global minima, global maxima or finding the roots of nonlinear equations.

There's no place like home : unhomely moments in three postcolonial picture books

One of the principal strands of postcolonial theory and critical practice is the interrogation of received versions of colonial history. This paper investigates the extent to which three contemporary picture books, Gavin Bishop's The House that Jack Built, John Marsden and Shaun Tan's The Rabbits, and Thomas King and William Kent Monkman's A Coyote Columbus Story, mobilise postcolonial strategies in their representations of place. In particular, it focuses on how postcolonial textuality unsettles and transgresses notions of "homeliness" in narratives involving the displacement of colonised and colonising peoples. As the shifting power relations of colonialism render unhomely what has previously been homely (especially for colonised peoples), so they involve a contrary move in which unhomely spaces are changed into simulacra of lost or abandoned homes. Drawing upon Walter Benjamin's formulation of materialist historiography, Homi Bhabha describes what he terms 'the unhomely moment' as that in which personal and psychic histories intersect with the violent dislocations of colonialism. This paper will argue that such unhomely moments shape the visual and verbal narratives of The House that Jack Built, The Rabbits and A Coyote Columbus Story, all of which deal with the trauma which occurs when cultures previously geographically and psychically distant are brought into close contact with each other. Written to and for children who are citizens of postcolonial cultures, these texts disclose the unease which persists in contemporary societies where colonial histories are rehearsed and revisioned. However, the paper will argue that the three texts position readers in quite different ways; for instance, while the verbal text of The Rabbits constructs an implied author capable of speaking for the colonised and offering readers a very circumscribed subject position, Thomas King's narrative in A Coyote Columbus Story engages in a dialogic playfulness which allows readers to adopt a variety of reading positions. For each text, some key representations of unhomely moments will be considered, and the paper will explore the extent to which they construct forms of temporality which negotiate the space between history and its significances within crosscultural and intercultural formations.

Building autonomic clusters: a response to IBM's autonomic computing challenge

IBM has announced Autonomic Computing as one of its Grand Challenges. A list of characteristics was generated to describe an autonomic computing system. Many researchers and research group have responded positively to the challenge by initiating research around one or two of the characteristics identified by IBM as the requirements for Autonomic Computing. We have addressed the IBMs request to contribute to the challenge by building an autonomic operating system that possesses nearly all IBM characteristics. This paper contains our response to the IBMs Autonomic Computing Challenge.

Towards ending the silence: working women as carers of children with chronic illness/disability

This research presents stories from Australian women who work and care for a child with a significant chronic illness or disability. The paper considers the theory of Silencing the Self (Jack, 1991) in relation to the reported experiences and behaviours of these women. We report three themes of Caring and Working: "Otherness", "Doing it All" - but "Wanting to Live a Normal Life". As in Jack's study, these women engaged in silencing of the self. However, we also observed other people contributing to their silence and, unlike the respondents in Jack's study, many of these women fought the silence and did not accept that their unhappy situations should continue. They sought a life where silencing may not have been necessary.

Effect of proximity to the shelf edge on the diet of female Australian fur seals

The Australian fur seal Arctocephalus pusillus doriferus is a temperate latitude species with a breeding distribution restricted to Bass Strait, Australia. Recent studies of the foraging behaviour of female Australian fur seals indicated that they feed demersally in the shallow continental shelf waters, a behaviour that is in contrast to the epipelagic foraging of females of most other arctocephaline (Southern Hemisphere fur seals) species and akin to that observed in sea lions. These studies, however, were conducted at one colony (Kanowna Island) located in central northern Bass Strait, and it was suggested that the observed foraging behaviour may have been due to the distance of this colony from the continental shelf edge (180 km), making it inefficient to forage beyond it. Here, the diet of lactating Australian fur seals was compared between 2 colonies to test if differing proximity to the continental shelf edge resulted in differences in foraging behaviour. The 2 breeding colonies studied, Kanowna Island and The Skerries, were 180 and 25 km from the nearest shelf edge, respectively. We analysed a total of 917 scat samples collected at the 2 colonies between 1997 and 2001. From faecal analysis, 45 primarily demersal on-shelf species of fishes and cephalopods were identified. Only 4 species had a frequency of occurrence greater than 10%: redbait Emmelichthys nitidus, jack mackerel Trachurus sp., red rock cod Pseudophycis bachus, and Gould’s squid Nototodarus gouldi. No seasonal, annual or spatial differences were found between the 2 colonies, indicating that proximity to the shelf edge does not influence diet.

The influence of age on reproductive success and diet in Australasian gannets (Morus Serrator) breeding at Pope's Eye, Port Phillip Bay, Victoria

The influence of age on reproductive success and diet was examined in ‘old’ (experienced; 12 years and older) and ‘young’ (5–8 years of age) Australasian gannets (Morus serrator) breeding at Pope’s Eye, Port Phillip Bay, Victoria during the 2002–2003 breeding period. Although food availability, as indicated by commercial fish catches, throughout this breeding period was low, there were no significant differences in breeding success or chick growth between groups. Nevertheless, old birds tended to have higher reproductive success, replacing more lost eggs and fledging chicks of a greater mass. However, old birds also laid more eggs that failed to hatch. Five fish species, including jack mackerel (Trachurus declivis), barracouta (Thyrsites atun), redbait (Emmelichthys nitidus), anchovy (Engraulis australis) and red mullet (Upeneichthys vlamingii), were important in the gannet diet during this breeding period. There were no significant differences in dietary parameters, including range of species and size of prey, between old and young gannets, nor were there any differences between those of the chicks and their parents, suggesting that adults do not forage selectively for their chicks. This study showed that even during a period of presumed low food availability, when experienced (older) birds might be expected to have enhanced success, the differences between these and less experienced (younger) birds may not be apparent.

Towards ending the silence: working women caring for children with chronic illness

This paper presents stories from women who work and care for a child with a significant chronic illness or disability. The purpose of this paper is to move towards ending the silence on their lives. A three-phase emergent research design responds to the question: What is life like for a full-time worker who is concurrently the primary carer of a chronically ill child? This paper considers the theory of Silencing the Self (Jack, 1991) in relation to the emergent themes of “Otherness” and “Doing it All.” As in Jack’s study, these women also engaged in silencing of the self. However, unlike the respondents in Jack’s study, these women did not demonstrate feelings of worthlessness and hopelessness for the future, nor were they alone in contributing to their silence. Indeed, many experienced silencing behaviors from others around them, and many rallied against the silence, not accepting that their burden should continue. Consideration of Jack’s theory is made to point out the distinctions between the women in this study and Jack’s study, and analytical commentary is provided to demonstrate the relevance of this analysis in light of the current debates surrounding the Work–Home Conflict and the rising levels of informal care provided by women in our communities.