Main streams and fine rivers : thinking the aporetics of edge

This paper takes up the question (reframed by Deleuze and Guattari) of where expansion takes place: at the ends or from the centre. Despite the connotations of mediocrity that can be attributed to the term ‘mainstream’, it is possible to rethink what happens at close range as the space of radical openings. Writers can often believe that what is most abnormal or fringe will produce the highest probability of creative ‘event’. The question, however, can be posed – framed by the lineage of deconstruction – whether the key to unlocking any system of totality or closed possibility may lie in a very central (although physically peripheral) location. If, instead of the classical image, expansion may occur from re-imagined ‘middles’ rather than conventional ‘margins’, this reading of where potential can arise may offer a more resilient model than that of fragile peripheries, forever exposed to being amputated from staid centres of status and restricted participation. Drawing on the writings of Deleuze and Guattari, Derrida and Badiou, this paper seeks to unsettle any simplistic approach to the notion of edge, reinscribing it within the repetitiveness of our situations, to argue that right in the middle of the so-called mainstream, there might be the fine rivers of aporia that when encountered in thought can constitutes gates to that which is most radical in writing and other creative practices.

On the edge of the desert : design and planning for Roxby Downs

The design and planning of settlements in arid Australia has long been wrought with difficulties because they are positioned in the extremes of environmental and social contexts. Historically many mining-related settlements in Western Australia (WA), South Australia (SA), Northern Territory (NT) and Queensland have struggled or failed in realising a quality design and plan, but also to sustain a robust and vibrant community who do not wish to escape to mainstream suburbia or simply operate as a fly-in fly-out employer commuter from this suburbia. Places like Mt Isa, Theodore, Moranbah, Broken Hill, Radium Hill, Leigh Creek, Roxby Downs, Paraburdoo, Shay Gap, Karratha are typical of these circumstances.

This paper reviews the design and planning origins of the villages at Olympic Dam, and critiques the future designs embedded in the Olympic Dam Expansion Environmental Impact Statement [EIS] (2009). These villages consist of Olympic dam village ( a fly-in fly-out dong-go containerised community accommodating some 500 workers) and Roxby Downs (a mixed Adelaide-template suburb with temporary village and caravan park insertions accommodation some 4,500 ‘permanent’ residents and some 200 fly-in fly-out ‘workers’). The scenario presented in the EIS is to demolish the former and establish a new village for some 10,000 workers, and expand Roxby Downs from 4,500 to near 20,000 although whether this later figure will occur is unclear but certainly the infrastructure and facilities have to be increased as well as increasing residential accommodation units).

Urban ecologies at the edge : a case study

This paper discusses some central theoretical and methodological constructs in the field of urban ecologies, identifies research gaps in the field, and uses the Victoria Laboratory of Urban Ecologies (VALUE) as a case study illustrating possible directions of future urban ecologies research. It begins by tracing the theoretical roots of urban ecologies before reviewing contemporary urban ecologies studies throughout the world. Two critical gaps in urban ecologies research are identified, suggesting opportunities for future studies. The paper then introduces the research teams and projects of VALUE – a research centre hosted by the School of Architecture and Building at Deakin University. The paper concludes that the research activities in VALUE are at the edge of urban ecologies research due to the interdisciplinary nature of collaboration in and between project teams, which have thus been able to address gaps in urban ecologies research and make important contributions to the field.

Dynamic threshold determination by local and global edge evaluation

In this paper we consider two methods for automatically determining values for thresholding edge maps. In contrast to most other related work they are based on the figural rather than statistical properties of the edges. The first approach applies a local edge evaluation measure based on edge continuity and edge thinness to determine the threshold on edge magnitude. The second approach is more global and considers complete connected edge curves. The curves are mapped onto an edge curve length/average magnitude feature space, and a robust technique is developed to partition this feature space into true and false edge regions. A quantitative assessment of the results on synthetic data shows that the global method performs better than the local method. Furthermore, a qualitative assessment of its application to a variety of real images shows that it reliably produces good results.

Early jump-out corner detectors

We present two new corner detectors; one works by using dissimilarity along the contour direction to detect curves in the image contour and the other estimates image curvature along the contour direction. These operators are fast, robust to noise, and require no subjective thresholding.

Edge evaluation using necessary components

We classify all the different kinds of errors that can occur in edge detection and then develop measures for quantifying these errors. It is shown that these sets of measures are complete and independent and form necessary components of an edge-evaluation scheme. The principle that an edge-evaluation measure should have certain qualitative properties is used to develop a method for combining these error components into a single combined measure.

Neighborhood coherence and edge based approaches to film scene extraction

In order to enable high-level semantics-based video annotation and interpretation, we tackle the problem of automatic decomposition of motion pictures into meaningful story units, namely scenes. Since a scene is a complicated and subjective concept, we first propose guidelines from film production to determine when a scene change occurs in film. We examine different rules and conventions followed as part of Film Grammar to guide and shape our algorithmic solution for determining a scene boundary. Two different techniques are proposed as new solutions in this paper. Our experimental results on 10 full-length movies show that our technique based on shot sequence coherence performs well and reasonably better than the color edges-based approach.

2-D edge feature extraction to subpixel accuracy using the generalized energy approach

Precision edge feature extraction is a very important step in vision, Researchers mainly use step edges to model an edge at subpixel level. In this paper we describe a new technique for two dimensional edge feature extraction to subpixel accuracy using a general edge model. Using six basic edge types to model edges, the edge parameters at subpixel level are extracted by fitting a model to the image signal using least-.squared error fitting technique.

Dynamic threshold determination by local and global edge evaluation

In this paper we consider two methods for automatically determining values for thresholding edge maps. Rather than use statistical methods they are based on the figural properties of the edges. Two approaches are taken. We investigate applying an edge evaluation measure based on edge continuity and edge thinness to determine the threshold on edge strength. However, the technique is not valid when applied to edge detector outputs that are one-pixel wide. In this case, we use a measure based on work by Lowe for assessing edges. This measure is based on length and average strength of complete linked edge lists.

Reliability and validity of the Melbourne edge test and high/low contrast visual acuity chart

Purpose. The purposes of the study were to investigate the test-retest reliability and the validity of new versions of the Melbourne Edge Test (MET) and the High/Low Contrast Visual Acuity (H/LCVA) chart and to investigate the agreement between the original and new versions.

Methods. The MET original photographic version, MET new light box version, H/LCVA Chart original photographic version, H/LCVA Chart new printed version, and the Pelli-Robson chart were administered twice to one eye of 22 subjects with low vision and 20 soft contact lenses wearers.

Results. For the low vision group, the test-retest 95% limits of agreement were ±5.2 dB for the MET new light box version and ±0.39 logarithm of the minimum angle of resolution (logMAR) for the LCVA component of the H/LCVA new printed version. For the soft contact lens group, the test-retest 95% limits of agreement were ±2.1 dB for the MET new light box version and ± 0.26 logMAR for the LCVA component of the H/LCVA new printed version. Moderate to high correlations were obtained between contrast sensitivity tests, thus providing evidence of validity. Scores obtained for the new test versions were significantly higher than the original versions (p < 0.01).

Conclusions. Of all the tests administered, the MET original photographic version and the Pelli-Robson Chart had the highest test-retest reliability for the low vision group. For the soft contact lens group, the H/LCVA original version (low contrast letters, 18% Weber) and the Pelli-Robson Chart had the highest reliability.