EBSD study of the orientation dependence of substructure characteristics in a model Fe-30wt%Ni alloy subjected to hot deformation

The aim of the present investigation was to determine the orientation dependence of substructure characteristics in an austenitic Fe−30wt%Ni model alloy subjected to hot plane strain compression. Deformation was carried out at a temperature of 950 °C using a strain rate of 10 s^₋₁ to equivalent strain levels of approximately 0.2, 0.4, 0.6 and 0.8. The specimens obtained were analysed using a fully automatic electron backscatter diffraction technique. The crystallographic texture was characterized for all the strain levels studied and the subgrain structure was quantified in detail at a strain of 0.4. The substructure characteristics displayed pronounced orientation dependence. The major texture components, namely the copper, S, brass, Goss and rotated Goss, generally contained one or two prominent families of parallel larger-angle extended subboundaries, the traces of which on the longitudinal viewing plane appeared systematically aligned along the {111} slip plane traces, bounding long microbands subdivided into slightly elongated subgrains by short lower-angle transverse subboundaries. Relatively rare cube-orientated grains displayed pronounced subdivision into coarse deformation bands containing large, low-misorientated subgrains. The misorientation vectors across subboundaries largely showed a tendency to cluster around the sample transverse direction. Apart from the rotated Goss texture component, the stored energy levels for the remaining components were principally consistent with the corresponding Taylor factor values.

Sub-surface geology of the Kerang District, Murray Basin, Southeast Australia

The subsurface geology of the Kerang District was examined. The stratigraphic relationships between the Cenozoic western marine and eastern non-marine provinces of the Riverine Plain of the Murray Basin are now far better understood. A new three-fold subdivision of the Renmark Group, including the new Mystic Park Formation, is proposed.

Procedural modeling facilities for hierarchical object generation

We modify a selection of interactive modeling tools for use in a procedural modeling environment. These tools are selection, extrusion, subdivision and curve shaping. We create human models to demonstrate that these tools are appropriate for use on hierarchical objects. Our tools support the main benefits of procedural modeling, which are: the use of parameterisation to control and very a model, varying levels of detail, increased model complexity, base shape independence and database amplification. We demonstrate scripts which provide each of these benefits.

Duplicating road patterns in South African informal settlements using procedural techniques

The formation of informal settlements in and around urban complexes has largely been ignored in the context of procedural city modeling. However, many cities in South Africa and globally can attest to the presence of such settlements. This paper analyses the phenomenon of informal settlements from a procedural modeling perspective. Aerial photography from two South African urban complexes, namely Johannesburg and Cape Town is used as a basis for the extraction of various features that distinguish different types of settlements. In particular, the road patterns which have formed within such settlements are analysed, and various procedural techniques proposed (including Voronoi diagrams, subdivision and L-systems) to replicate the identified features. A qualitative assessment of the procedural techniques is provided, and the most suitable combination of techniques identified for unstructured and structured settlements. In particular it is found that a combination of Voronoi diagrams and subdivision provides the closest match to unstructured informal settlements. A combination of L-systems, Voronoi diagrams and subdivision is found to produce the closest pattern to a structured informal settlement.

The role of community activism in the sustainable development of coastal communities : the Nepean Conservation Group Inc, a case study

The Nepean Conservation Group Inc (NCG) was formed in 1973. The jurisdiction of the NCG covers the whole the Nepean Peninsula, the tiny sliver of land between Port Phillip Bay and Bass Strait, at the end of the Mornington Peninsula, Victoria, Australia. Much of the Nepean Peninsula is moonah woodland. The NCG Constitution states that their primary object is “To make every effort to ensure that the land and waters of the Sorrento Portsea Blairgowrie Area are used with wisdom and foresight and that the competing demands upon them are resolved in the best long terms interests thereof …” The NCG deals with issues as diverse as vegetation and development overlays; heritage; townscapes; public access; neighbourhood character; hooded plovers; historic towns and fire protection. The NCG coordinates Friends Groups that care for bushland parks and coastal reserves, for flora and fauna, on the Nepean Peninsula. The NCG is an advocate for a dynamic fragile coast. Implicit is an expectation that such a local community group is the guardian of their coastal environment. After thirty-eight years of dedicated voluntary work it is timely to reconsider the role of community activism in the sustainable development of coastal regions and towns. This paper examines a number of significant recent issues: public rights to access; subdivision; historic coastal town development and fire protection. The author acknowledges the NCG Committee for their support and access to the NCG papers and archives. This case study is situated in a larger ongoing research investigation.

Fine-scale effects of habitat loss and fragmentation despite large-scale gene flow for some regionally declining woodland bird species

Habitat loss and associated fragmentation effects are well-recognised threats to biodiversity. Loss of functional connectivity (mobility, gene flow and demographic continuity) could result in population decline in altered habitat, because smaller, isolated populations are more vulnerable to extinction. We tested whether substantial habitat reduction plus fragmentation is associated with reduced gene flow in three 'decliner' woodland-dependent bird species (eastern yellow robin, weebill and spotted pardalote) identified in earlier work to have declined disproportionately in heavily fragmented landscapes in the Box-Ironbark forest region in north-central Victoria, Australia. For these three decliners, and one 'tolerant' species (striated pardalote), we compared patterns of genetic diversity, relatedness, effective population size, sex-ratios and genic (allele frequency) differentiation among landscapes of different total tree cover, identified population subdivision at the regional scale, and explored fine-scale genotypic (individual-based genetic signature) structure. Unexpectedly high genetic connectivity across the study region was detected for 'decliner' and 'tolerant' species. Power analysis simulations suggest that moderate reductions in gene flow should have been detectable. However, there was evidence of local negative effects of reduced habitat extent and structural connectivity: slightly lower effective population sizes, lower genetic diversity, higher within-site relatedness and altered sex-ratios (for weebill and eastern yellow robin) in 10 x 10 km 'landscapes' with low vegetation cover. We conclude that reduced structural connectivity in the Box-Ironbark ecosystem may still allow sufficient gene flow to avoid the harmful effects of inbreeding in our study species. Although there may still be negative consequences of fragmentation for demographic connectivity, the high genetic connectivity of mobile bird species in this system suggests that reconnecting isolated habitat patches may be less important than increasing habitat extent and/or quality if these need to be traded off.

Estuary environmental flows assessment methodology for Victoria

This report sets out a method to determine the environmental water requirements of estuaries in Victoria. The estuary environmental flows assessment method (EEFAM) is a standard methodology which can be applied consistently across Victorian estuaries.
The primary objective of EEFAM is to define a flow regime to maintain or enhance the ecological health of an estuary. The method is used to inform Victorian water resource planning processes.
The output of EEFAM is a recommended flow regime for estuaries. This recommendation is developed from the known dependence of the estuary’s flora, fauna, biogeochemical and geomorphological features on the flow regime. EEFAM is an evidence-based methodology. This bottom-up or ‘building block’ approach conforms to the asset-based approach of the Victorian River Health Strategy and regional river health strategies.
EEFAM is based on and expands on FLOWS, the Victorian method for determining environmental water requirements in rivers. The list of tasks has been modified and re-ordered in EEFAM to reflect environmental and management issues specific to estuaries. EEFAM and FLOWS can be applied
simultaneously to a river and its estuary as part of a whole-of-system approach to environmental flow requirements. Like the FLOWS method, EEFAM is modular, and additional components can be readily incorporated.

A new urban planning code's impact on walking: The residential environments project

Objectives. We examined whether people moving into a housing development designed according to a state government livable neighborhoods subdivision code engage in more walking than do people who move to other types of developments.

Methods. In a natural experiment of 1813 people building homes in 73 new housing developments in Perth, Western Australia, we surveyed participants before and then 12 and 36 months after moving. We measured self-reported walking using the Neighborhood Physical Activity Questionnaire and collected perceptions of the environment and self-selection factors. We calculated objective measures of the built environment using a Geographic Information System.

Results. After relocation, participants in livable versus conventional developments had greater street connectivity, residential density, land use mix, and access to destinations and more positive perceptions of their neighborhood (all P < .05). However, there were no significant differences in walking over time by type of development (P > .05).

Conclusions. Implementation of the Livable Neighborhoods Guidelines produced more supportive environments; however, the level of intervention was insufficient to encourage more walking. Evaluations of new urban planning policies need to incorporate longer term follow-up to allow time for new neighborhoods to develop.

The constructional geometry of early Javanese temples

The early development of Hindu Javanese architecture can be traced through interpretation of epigraphs, archaeological excavations, and comparison of extant temples with other traditions. However, while many scholars have speculated on connections between Javanese Hindu temples and presumed antecedents in India, these have been made on the basis of visual comparison and epigraphic interpretations. No Indian temple has been conclusively shown to be a model for the earliest Javanese temples. Archaeologist and temple historian Michael Meister has shown in his analysis of the geometric composition of early Hindu temples in South Asia how a ritual sixty-four square mandala was the geometric basis of temple construction during the formative period (fifth to eighth century) of the Indian architectural tradition. Working from an understanding of temple construction sequence as well as their ritual underpinnings, Meister found that the sixtyfour square mandala's dimensions correlate closely to the constructed dimensions at the level of the vedibandha (which corresponds with the plan level of the sanctuary threshold). Furthermore, he shows how the horizontal profile of the cella depends on the number of offsets and the proportional relationships between ech offset based on the subdivision of the sixty-four square grid. The authors have investigated whether a similar compositional basis can be found for the earliest Javanese temples on the Dieng Plateau in the highlands of central Java, despite differences in architectonic and symbolic expression. The analysis of relationships between ritual geometry and actual temple layouts for these buildings has the potential to furthering our understanding of the connections between Hindu temples in Java and those in India.

Foveal contrast processing of increment and decrement targets is equivalently reduced in glaucoma

Background: 

An endangered arboreal specialist, the western ringtail possum (Pseudocheirus occidentalis), shows a greater genetic divergence across a narrow artificial waterway than a major road

The fragmentation of habitats by roads and other artificial linear structures can have a profound effect on the movement of arboreal species due to their strong fidelity to canopies. Here, we used 12 microsatellite DNA loci to investigate the fine-scale spatial genetic structure and the effects of a major road and a narrow artificial waterway on a population of the endangered western ringtail possum (Pseudocheirus occidentalis) in Busselton, Western Australia. Using spatial autocorrelation analysis, we found positive genetic structure in continuous habitat over distances up to 600 m. These patterns are consistent with the sedentary nature of P. occidentalis and highlight their vulnerability to the effects of habitat fragmentation. Pairwise relatedness values and Bayesian cluster analysis also revealed significant genetic divergences across an artificial waterway, suggesting that it was a barrier to gene flow. By contrast, no genetic divergences were detected across the major road. While studies often focus on roads when assessing the effects of artificial linear structures on wildlife, this study provides an example of an often overlooked artificial linear structure other than a road that has a significant impact on wildlife dispersal leading to genetic subdivision.