Ergonomics and sustainability: Towards and embrace of complexity and emergence

Technology offers a promising route to a sustainable future, and ergonomics can serve a vital role. The argument of this article is that the lasting success of sustainability initiatives in ergonomics hinges on an examination of ergonomics' own epistemology and ethics. The epistemology of ergonomics is fundamentally empiricist and positivist. This places practical constraints on its ability to address important issues such as sustainability, emergence and complexity. The implicit ethical position of ergonomics is one of neutrality, and its positivist epistemology generally puts value-laden questions outside the parameters of what it sees as scientific practice. We argue, by contrast, that a discipline that deals with both technology and human beings cannot avoid engaging with questions of complexity and emergence and seeking innovative ways of addressing these issues.No Full Tex

An annotated checklist of the fishes of the Swan-Avon River system, Western Australia

The checklist of the fishes of the Swan-Avon River System in south-western Australia given in this paper is based on the collections and records held by the Western Australian Museum, and on the results of a recent extensive sampling programme carried out with beach seines, trawls and mesh nets. The latter study has also provided data on the distribution of many of the species within the river system. The 110 species recorded are predominantly of marine origin and can be regarded either as marine “stragglers”, or as fish which utilize the estuary predominantly as a nursery area or adult feeding ground, or as an environment that can be exploited at various times during the life cycle. Several of the most abundant species are, however, represented by populations that can pass through the whole of their life cycle within the Swan-Avon River system. Although, as with other south-western Australian rivers, the indigenous freshwater fish component is highly impoverished, its abundance in this system has also suffered from the effects of damming, periods of “drying-up”, eutrophication and run-off from agricultural land. At the same time, some of the changes brought about by damming have produced conditions favourable for the establishment of populations of certain introduced species. Comparisons between the fish fauna of the Swan-Avon River System and the limited data for other Western Australian coastal rivers suggest that Cape Naturaliste represents the approximate southern limit of the distribution of many northern species, while the corresponding point for the northwards extension of several southern species is in the region of the North West Cape

The inshore fish faunas over soft substrates and reefs on the tropical west coast of Australia differ and change with latitude and bioregion

Aim To test the following hypotheses regarding ichthyofaunal compositions along an extensive tropical coastline. The compositions over soft substrates and reefs: (1) consistently differ markedly; (2) change progressively with latitude and temperature through sequential changes in the abundances of certain species; and (3) vary among bioregions, as those regions differ markedly in their environmental characteristics. Location Tropical north-western Australia. Methods Similarity matrices, derived from percentage contributions of each fish species to catches obtained over soft substrates by trawling and over reefs by trapping at seven regularly spaced sites along 1500 km of coast, were subjected to cluster analysis, non-metric multidimensional scaling ordination and associated tests. Results In total, 361 species were obtained by trawling and trapping along the tropical coast of north-western Australia (NWA). Only 56 species were recorded over both soft substrates and reefs, whereas 229 and 76 species were caught exclusively over soft substrates and reefs, respectively. The Leiognathidae, Carangidae and Terapontidae contributed most individuals (62.2%) to catches over soft substrates, whereas the Lethrinidae and Lutjanidae dominated those over reefs (81.9%). The species compositions in both habitats were related to latitude and water temperature. Ichthyofaunal compositions in the Kimberley region differed markedly from those in the Canning/Pilbara regions further south, which, in turn, each had distinct characters. The vast majority of species found over both habitats also occur in the Pacific Ocean to the north. Main conclusions The most important fish families over soft substrates and reefs in inshore marine waters of tropical NWA differ markedly. The ichthyofaunal compositions of both habitats undergo similar patterns of progressive change with latitude, due to site-staggered changes in the relative abundances of key fish species in their respective habitats. Ichthyofaunal composition in both habitats was found to be influenced by water temperature. The latitudinal trends exhibited by species composition are overlaid on a strong bioregional effect, reflecting the influence of the very different environmental conditions in those bioregions, which include marked differences in such factors as tidal regime, turbidity and whether mangroves are nearby. The important contribution of species with a Pacific affinity was presumably facilitated by the polewards-flowing Indonesian Throughflow, which links the Pacific Ocean with waters bordering the NWA coast

System requirements analysis and technological support for the Ballistic Missile Defense System (BMDS): FY07 progress report

Engineering of the Ballistic Missile Defense System (BMDS) requires one to take a holistic approach that includes the physical modeling and analysis of the missile defense operating environment, development of metrics and techniques to analyze the communication requirements of the net-centric Ballistic Missile Defense warfare, and the use of architectural patterns and other software technologies to shape the emergent behavior of the BMDS taking into account of the system's interoperability, composability, extensibility, and dynamic reconfigurability. This report summarizes the work in FY07 to investigate new technologies to support the development of the BMDS. We developed new scoring functions for the fusion of sensor data, an algorithm for multiple hypothesis tracking, a distributed medium access control protocol and data dissemination algorithm for wireless networks of cooperative radar systems, simulation models for network-centric electronic warfare metrics study and for the prediction of the over the horizon radar system footprints, technologies for the correct specification and validation of temporal behaviors in a Service-Oriented Architecture (SOA) based system-of-systems, runtime verification of system-level requirements of distributed reactive systems using MSC-Assertions, and safety assurance of reconfigurable and selfreconfigurable systems. We also evaluated the effectiveness of the real-time Java technology for BMDS software and the potential impact of integrating the Air Force YAL-1A Attack Laser into the BMDS.Approved for public release; distribution is unlimited