978 resultados para Mine timbering.


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Freestone (1989+) has extensively surveyed town planning visions and model communities for Australia, but one settlement has been forgotten. The significant mining settlement of Broken Hill in far western New South Wales does not figure in his thematic and historical analyses yet its park lands are so integral to its physical cultural legacy and human health that it warrants enhanced standing. In the last 2 years the Commonwealth has been considering the potential nomination of the municipality of Broken Hill for inclusion onto the National Heritage List principally due to its mining, social and economic contributions to Australia’s heritage and identity. A component in their deliberations is the Park Lands, or ‘Regeneration Reserves’, that encompass this urban settlement and its mine leaseholds. Within these Regeneration Reserves, international arid zone ecological restoration theory and practice was pioneered by Albert and Margaret Morris in the 1930s that serves as the method for all mining revegetation practice in Australia today. This paper reviews the theory and evolution of the Broken Hill Regeneration Reserves, having regard to the Adelaide Park Lands and Garden City discourses of the 1920s-30s, arguing that the Broken Hill Regeneration Reserves have a valid and instrumental position in the planning and landscape architectural histories of Australia.

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Phishing emails are more active than ever before and putting the average computer user and organizations at risk of significant data, brand and financial loss. Through an analysis of a number of phishing and ham email collected, this paper focused on fundamental attacker behavior which could be extracted from email header. It also put forward a hybrid feature selection approach based on combination of content-based and behavior-based. The approach could mine the attacker behavior based on email header. On a publicly available test corpus, our hybrid features selections are able to achieve 96% accuracy rate. In addition, we successfully tested the quality of our proposed behavior-based feature using the information gain.

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My novel is a collection of interrelated stories. Each story is framed by the idiosyncrasies and prejudices of a different first-person voice. There are gaps in narrative time and there is disparity between the narrators’ voices. The result is a ‘discontinuous narrative’; this term describes the early work of Frank Moorhouse: ‘an innovative narrative method using interconnected stories’ (Griffith University 2011).
As I draft and re-draft the stories, I am forced to assess the interaction between the voices. I am aware of the disjuncture, and I ask myself: Why not tell the story through the eyes of one narrator? Why not choose a third-person perspective, an omniscient narrator who might collect all of the voices together, in a coherent way?
As I second-guess my approach, I realise that the splintering of voices feels like the right way to tell the story and, in this way, I approach the question of methodology. I am aware that a sense of disjuncture arises out of the medley of voices, but I also realise that the disjuncture is carefully constructed; it is not accidental. This is an intuitive judgement.
If I edit my novel ethically, I ask what the discontinuity achieves, rather than how it fails in the context of logic. This means that I recognise that the narrative begins from a place that does not worry about logic, and I realise that second-guessing the surface content of the narrative, from a rational perspective, may be counterproductive.
The conscious mind, fettered as it is with inhibitions, may fail to see that the logical track is not necessarily the most productive route. The conscious mind may not recognise that going off-track is the way forward and, perhaps, the only way that the story can become something other than what I, in my rational mind, believe that it should be.
Ethical editing means that I am attentive to my intuitive response to the narrative; it means that I tolerate incongruous elements of the narrative, even if they do not fit the criteria of logic.
Ethical editing is a meeting of minds (both mine); the fully conscious mind meets the work of the subconscious mind with surprise and approval, at best, skepticism and derision, at worst. The work of the subconscious mind is elusive but it need not be subjugated to logical, rational considerations, for this means that I delimit the work of the subconscious; it means I assess the discontinuity on the basis of an external operating system; it means that I impose certain criteria upon the surface narrative, criteria that has nothing to do with understanding why the discontinuity exists in the first instance.
Alternatively, when I pay heed to a primal moment of narrative composition, a moment that is not necessarily consciously determined or logical, I apprise the surface of the narrative as a metaphorical map, I attempt to engage with the possibilities for meaning that the map encompasses; this constitutes a quest for the unstable how of meaning attribution.

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Actigraph accelerometers are hypothesized to be valid measurements for assessing children's sedentary time. However, there is considerable variation in accelerometer cut-points used. Therefore, we compared the most common accelerometer sedentary cut-points of children performing sedentary behaviors. Actigraph Actitrainer uniaxial accelerometers were used to measure children's activity intensity (29 children, 5-11 years old) during different activities, namely playing computer games, nonelectronic sedentary games, watching television and playing outdoors. A structured protocol was the criterion for assessing the validity of four common cut-points (100, 300, 800, 1100 counts/minute). The median counts during all sedentary behaviors were below the lowest comparison cut-point of 100 cpm. The 75th percentile values for the sedentary behaviors were always below the cut-point of 300 cpm. Our results suggest that the cut-point of <100 cpm is the most appropriate.

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This poem plays around with ideas of ‘voice’. The title draws attention, through its use of a demonstrative pronoun, to the instability of voice in lyric poetry. In other words, by calling the poem ‘This Voice’, I hope to make the reader think ‘Which voice is this? The author’s? Mine? A fictional character’s?’

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Discovering frequent patterns plays an essential role in many data mining applications. The aim of frequent patterns is to obtain the information about the most common patterns that appeared together. However, designing an efficient model to mine these patterns is still demanding due to the capacity of current database size. Therefore, we propose an Efficient Frequent Pattern Mining Model (EFP-M2) to mine the frequent patterns in timely manner. The result shows that the algorithm in EFP-M2l is outperformed at least at 2 orders of magnitudes against the benchmarked FP-Growth.

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Indirect pattern is considered as valuable and hidden information in transactional database. It represents the property of high dependencies between two items that are rarely occurred together but indirectly appeared via another items. Indirect pattern mining is very important because it can reveal a new knowledge in certain domain applications. Therefore, we propose an Indirect Pattern Mining Algorithm (IPMA) in an attempt to mine the indirect patterns from data repository. IPMA embeds with a measure called Critical Relative Support (CRS) measure rather than the common interesting measures. The result shows that IPMA is successful in generating the indirect patterns with the various threshold values.

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Coal handling is a complex process involving different correlated and highly dependent operations such as selecting appropriate product types, planning stockpiles, scheduling stacking and reclaiming activities and managing train loads. Planning these operations manually is time consuming and can result in non-optimized schedules as future impact of decisions may not be appropriately considered. This paper addresses the operational scheduling of the continuous coal handling problem with multiple conflicting objectives. As the problem is NP-hard in nature, an effective heuristic is presented for planning stockpiles and scheduling resources to minimize delays in production and the coal age in the stockyard. A model of stockyard operations within a coal mine is described and the problem is formulated as a Bi- Objective Optimization Problem (BOOP). The algorithm efficacy is demonstrated on different real-life data scenarios. Computational results show that the solution algorithm is effective and the coal throughput is substantially impacted by the conflicting objectives. Together, the model and the proposed heuristic, can act as a decision support system for the stockyard planner to explore the effects of alternative decisions, such as balancing age and volume of stockpiles, and minimizing conflicts due to stacker and reclaimer movements.

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Email has become the critical communication medium for most organizations. Unfortunately, email-born attacks in computer networks are causing considerable economic losses worldwide. Exiting phishing email blocking appliances have little effect in weeding out the vast majority of phishing emails. At the same time, online criminals are becoming more dangerous and sophisticated. Phishing emails are more active than ever before and putting the average computer user and organizations at risk of significant data, brand and financial loss. In this paper, we propose a hybrid feature selection approach based combination of content-based and behaviour-based. The approach could mine the attacker behaviour based on email header. On a publicly available test corpus, our hybrid features selection is able to achieve 94% accuracy rate.

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In May 2010, a delegation of Papua New Guinean politicians travelled to a remote village on the country’s north coast to receive a petition against proposed mine activity. The encounter between the politicians and the villagers who had invited them involved two very different articulations of power and authority, and two competing cartographies of centrality and marginality. The encounter speaks to the need to approach the concepts of custom and modernity not only as powerful discourses which are taken up and performed in local places, but also as analytical descriptors of actually existing patterns of practice and meaning which are structurally and ontological distinct. At the same time, however, analysis of the encounter between villagers and politicians makes clear that this structural difference cannot be written straightforwardly onto the social bodies of opposing collectivities. Rather, customary and modern forms of social relations exist in dynamic and ambivalent entanglements, pulled into contingent and differently weighted configurations by actors in local places.

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Background 

To investigate the interpersonal and physical environment mediators of the Transform-Us! mid-intervention effects on physical activity (PA) during recess and lunchtime.

Methods
Transform-Us! is a clustered randomised school-based intervention with four groups: sedentary behaviour intervention (SB-I), PA intervention (PA-I), combined PA+SB-I and control group. All children in grade 3 from 20 participating primary schools in Melbourne, Australia were eligible to complete annual evaluation assessments. The outcomes were the proportion of time spent in moderate-to-vigorous PA (MVPA) and light PA (LPA) during recess and lunchtime assessed by accelerometers. Potential mediators included: perceived social support from teachers; perceived availability of line markings; perceived accessibility of sports equipment; and perceived school play environment. Generalised linear models were used and mediation effects were estimated by product-of-coefficients (a·b) approach.

Results
268 children (8.2 years, 57% girls at baseline) provided complete data at both time points. A significant intervention effect on MVPA during recess in the SB-I and PA-I groups compared with the control group (proportional difference in MVPA time; 38% (95% CI 21% to 57%) and 40% (95% CI 20% to 62%), respectively) was found. The perceived school play environment was significantly positively associated with MVPA at recess among girls. An increase in perceived social support from teachers suppressed the PA+SB-I effect on light PA during recess (a·b= −0.03, 95% CI −0.06 to −0.00). No significant mediating effects on PA during recess and lunchtime were observed.

Conclusions
A positive perception of the school play environment was associated with higher MVPA during recess among girls. Future studies should conduct mediation analyses to explore underlying mechanisms of PA interventions.

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Many temperate estuaries have intermittently open and closed mouths, a feature that is often related to intermittent freshwater input. These systems, often overlooked due to their small size, can have large hydrological variability over medium-term time scales.

This variability presents potential difficulties for estuarine species particularly where anthropogenic alterations to freshwater flows can cause large deviations from natural patterns of tidal influence and inundation of habitat.

Influences of natural and hydrological variability on seagrasses were examined in two central Victorian estuaries with anthropogenically-modified but naturally-intermittent freshwater flows and mouth openings. Comparisons were focused on differences between an estuary with artificially-augmented freshwater inflow and an adjacent system, in which the volume and timing of inflows were altered by a reservoir. Eight additional estuaries in the region were also used to provide a context for these two main sites.

Hydrological changes during the three-year field component were affected by the ending of a drought and then a major flood a year later as well as by ongoing anthropogenic flow reduction and augmentation. These influences on hydrology were associated with an initially high seagrass coverage that was substantially reduced and showed signs of recovery only in the system that was affected by lower inflows. Such influences and responses also changed seasonally but to a much lesser extent than the responses to stochastic climatic events.

Natural flows were intermittent and varied substantially between years. Flooding flows represented up to 89% of the long-term annual average flow. Water quality was broadly typical of the region, with the exception of low pH in some tributaries, especially those of Anglesea estuary. Anthropogenic changes to flow were most evident at times of low natural flows and resulted in longer and more frequent periods of zero inflow to Painkalac estuary and a continual base flow to Anglesea. This base flow, from ponds containing coal ash, neutralised waters flowing from upstream and increased conductivity, except at times of high natural flow.

A three-state conceptual model of the magnitude and variability of water levels, based largely on the degree of tidal influence was identified and quantitatively assessed for the two estuaries that were the main focus of the study. These states in turn had a large influence on the area and inundation of benthic habitat. Floods tended to open the mouths of estuaries, which then remained tidal given sufficient flow to overcome sedimentary processes at the mouths. Low and zero inflow was a precondition for closure of the mouths of the estuaries. When closed, differences in inflow resulted in different endpoints in salinity patterns. From an initial pattern similar to a classic ‘salt wedge’, Painkalac estuary, with reduced inflow, quickly destratified and gradually became more saline, at times hypersaline. Anglesea estuary, with augmented flow, tended to remain stratified for longer until becoming completely fresh, given a long enough period of closure.

Episodic changes in the water quality of the estuaries were associated with different components of the freshwater flow regimes. At high flows, fresh waters of low pH with a high metal load entered Anglesea estuary. Except during the largest flood, when the estuary was completely flushed, this water was neutralised at the halocline and resulting in precipitation of metals. High flows into Painkalac were associated with elevated concentrations of clay-sourced suspended solids. During a closed period, with zero flow, a release of sediment-bound nutrients triggered by anoxia was observed in Painkalac, followed by an algal bloom.

The large decline in seagrass extent that was observed in both estuaries was closely related to floods and the subsequent reductions in potential habitat associated with the tidal states that followed. Analysis of historical patterns of extent against rainfall records suggested that periods of drought and extended mouth closures were related to establishment and expansion of beds. This model was similar to that described for South African estuaries and contrasted with more-seasonal patterns reported for local marine embayments.

Rates of in situ decomposition of seagrass detritus showed a mix of seasonal and disturbance-driven patterns of change, depending on estuary. Variability of these rates on a scale of 100s of metres was typically not significant, but there were a few episodes that were highly significant. A negative correlation between decomposition rate and seagrass extent was also observed. A novel technique for assessing cellulose decomposition potential in sediment, adapted from soil science, proved to be a useful tool for estuarine research. Results from this component of the study highlighted both small-scale variability that was inconsistent through time, and also stable differences in decomposition potential between depths and estuaries that were consistent with differences in hydrological state and salinity.

Given the relative lack of knowledge about processes in intermittent estuaries, particularly those relating to changes in freshwater inflow, results from this study will be of value both locally and for similar systems elsewhere. Locally, it is likely that flow regimes to both Anglesea and Painkalac estuaries will be reduced, following closure of the mine power station at Anglesea and due to increased demand from the reservoir above Painkalac. There is potential to manage flows from each of these sources to minimise downstream effects. Regionally, and globally, there are many intermittent estuaries in areas with Mediterranean-type climates. It has been predicted that the climates of these regions will become drier but with an increase in intensity of storm events, both of which have ramifications for flow regimes to estuaries. It is hoped that results of this study will contribute to more informed management of intermittent estuaries in the context of these likely changes.

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This paper examines how one indigenous community in the Western Province of Papua New Guinea (PNG) views the social responsibility initiatives of OK Tedi Mining Ltd (OTML). This mining operation has been controversial since its inception, and various operators of the mine have sought to engage the community and to undertake a number of CSR-related projects. Insights gained from four focus groups amongst the Ok Tedi River indigenous communities show that while some members of the community are satisfied with the company’s efforts at the macro level, many have reservations about the effectiveness of the programs at the micro level on the village and family unit. The implementation of CSR activities are slow and in many instances do not effectively address stakeholder concerns.

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Biodiversity offsets can be an important tool for maintaining or enhancingenvironmental values in situations where development is sought despite negativeenvironmental impacts. There are now approximately 45 compensatory mitigationprograms for biodiversity impacts worldwide, with another 27 programs in development. While offsets have great potential as a conservation tool, their establishment requires overcoming a number of conceptual and methodological hurdles. In Australia, new policy changes at the national and state (i.e., Western Australia) level require that offsets follow a set of general principles: (1) Environmental offsets may not be appropriate for all projects and will only be considered after avoidance and mitigation options have been pursued;(2) Environmental offsets will be based on sound environmental information andknowledge; (3) Establishing goals for offsets requires an estimate of expected direct and indirect impacts; (4) Environmental offsets will be focused on longer term strategic outcomes; (5) Environmental offsets will be cost-effective, as well as relevant and proportionate to the significance of the environmental value being impacted. Here we focus on the challenges of determining and implementing offsets using a real world example from a voluntary offset process undertaken for Barrick Gold’s Kanowna Belle mine site in Western Australia to highlight those challenges and potential solutions.