949 resultados para Rock bolt
Resumo:
This article discusses the production of an Indonesian rock past through a case study of the 1970s rock band God Bless, which has been gradually ‘coming back’ since the middle of the 2000s. In doing so, the article documents this comeback, analyses shifts in the band’s position vis-à-vis nationality, and places these shifts in the context of the industrial and aesthetic transformation of Indonesian popular music over the past decade or so. Furthermore, it considers how the range of nostalgic productions associated with the comeback might be understood not only in light of the scholarship on nostalgia, but also the political environment it inhabits.
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The Sydney rock oyster (Saccostrea glomerata) (SRO) is an oyster species that only occurs in estuaries along Australia's east coast. The SRO industry evolved from commercial gathering of oyster in the 1790s to a high production volume aquaculture industry in the 1970s. However, since the late 1970s the SRO industry has experienced a significant and continuous decline in production quantities and the industry's future commercial viably appears to be uncertain. The aim of this study was to review the history and the status of the SRO industry and to discuss the potential future prospects of this industry. This study summarised findings of the existing literature about the industry and defined development stages of the industry. Particular focus was put on the more recent development within the industry (1980s-present) which has not been covered adequately in the existing literature. The finding from this study revealed that major issues of the industry are linked to the management of prevailing diseases, the handling of water quality impairments from increasing coastal development, increasing competition from Australia's Pacific oyster (Crassostrea gigas) industry and the current socio-economic profile of the industry. The study also found that policy makers are currently confronted by the dilemma of saving a "dying art". Findings from this industry review may be vital for current and future fisheries managers and stakeholders as a basis for reviewing industry management and development strategies. This review may also be of interest for other aquaculture industries and fisheries who are dealing with similar challenges as the SRO industry.
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Socio-economic characteristics such as age, gender, educational attainment, employment status, and income contain vital information about how an industry may respond to changing circumstances, and hence are of importance to decision makers. While some socio-economic studies exist, relatively little attention has been given to fishery and aquaculture industries in regards to their socio-economic profiles and their role in the development prospects of these industries. In this study, by way of example, we focus on Australia’s Sydney rock oyster (Saccostrea glomerata) (SRO) industry. The aim of this study was identify the socio-economic profile of the SRO industry and to illustrate the value of such information for an industry management assessment. The SRO industry has experienced a major decrease in production volume since the late 1970 and continues to be affected by prevailing diseases and increasing market competition from Australia’s Pacific oyster (Crassostrea gigas) industry. It is likely that socio-economic aspects have influenced this development within the SRO industry. The socio-economic profile was developed using data from a SRO industry farm survey which was undertaken in 2012. Findings suggested that this industry is characterised by a mature aged oyster farmer population and a part-time oyster farming approach. These characteristics may affect the farmers’ ability to drive innovation and growth. The results also suggested that there may be potential industry entry barriers present in the SRO industry which may prevent younger people taking up oyster farming. Given the results, the study concluded that the current socio-economic profile of the industry has likely contributed to the present economic status quo of the industry.
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The Coalition's push to make changes to the Racial Discrimination Act was in part a response to a court ruling that Andrew Bolt had breached the Act over his comments about Aboriginal Australians. Here, Chelsea Bond revisits the newspaper columnist's treatment of Aboriginality, explaining that race is more than skin deep.
Resumo:
This thesis provides the first comprehensive assessment of the economic viability of Australia's Sydney rock oyster industry and forms the bases for future policy and industry management recommendations. In the four separate studies of the thesis, the socio-economic profile of the industry, the market price formation dynamics within Australia's oyster market, efficiency and productivity levels and the potential impact of climate change and market dynamics on the industry's future revenue were investigated. Findings of this project suggest, for example, that market dynamics may pose a greater thread to the future development of this industry than direct effect from climate change.
Resumo:
The Jericho kimberlite (173.1. ±. 1.3. Ma) is a small (~. 130. ×. 70. m), multi-vent system that preserves products from deep (>. 1. km?) portions of kimberlite vents. Pit mapping, drill core examination, petrographic study, image analysis of olivine crystals (grain size distributions and shape studies), and compositional and mineralogical studies, are used to reconstruct processes from near-surface magma ascent to kimberlite emplacement and alteration. The Jericho kimberlite formed by multiple eruptions through an Archean granodiorite batholith that was overlain by mid-Devonian limestones ~. 1. km in thickness. Kimberlite magma ascended through granodiorite basement by dyke propagation but ascended through limestone, at least in part, by locally brecciating the host rocks. After the first explosive breakthrough to surface, vent deepening and widening occurred by the erosive forces of the waxing phase of the eruption, by gravitationally induced failures as portions of the vent margins slid into the vent and, in the deeper portions of the vent (>. 1. km), by scaling, as thin slabs burst from the walls into the vent. At currently exposed levels, coherent kimberlite (CK) dykes (<. 40. cm thick) are found to the north and south of the vent complex and represent the earliest preserved in-situ products of Jericho magmatism. Timing of CK emplacement on the eastern side of the vent complex is unclear; some thick CK (15-20. m) may have been emplaced after the central vent was formed. Explosive eruptive products are preserved in four partially overlapping vents that are roughly aligned along strike with the coherent kimberlite dyke. The volcaniclastic kimberlite (VK) facies are massive and poorly sorted, with matrix- to clast-supported textures. The VK facies fragmented by dry, volatile-driven processes and were emplaced by eruption column collapse back into the volcanic vents. The first explosive products, poorly preserved because of partial destruction by later eruptions, are found in the central-east vent and were formed by eruption column collapse after the vent was largely cleared of country rock debris. The next active vent was either the north or south vent. Collapse of the eruption column, linked to a vent widening episode, resulted in coeval avalanching of pipe margin walls into the north vent, forming interstratified lenses of country rock-rich boulder breccias in finer-grained volcaniclastic kimberlite. South vent kimberlite has similar characteristics to kimberlite of the north vent and likely formed by similar processes. The final eruptive phase formed olivine-rich and moderately sorted deposits of the central vent. Better sorting is attributed to recycling of kimberlite debris by multiple eruptions through the unconsolidated volcaniclastic pile and associated collapse events. Post-emplacement alteration varies in intensity, but in all cases, has overprinted the primary groundmass and matrix, in CK and VK, respectively. Erosion has since removed all limestone cover.
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The demand for tunnelling and underground space creation is rapidly growing due to the requirement of civil infrastructure projects and urbanisation. Blasting remains the most inexpensive method of underground excavations in hard rock. Unfortunately, there are no specific safety guidelines available for the blasted tunnels with regards to the threshold limits of vibrations caused by repeated blasting activity in the close proximity. This paper presents the results of a comprehensive study conducted to find out the effect of repeated blast loading on the damage experienced by jointed basaltic rock mass during tunnelling works. Conducting of multiple rounds of blasts for various civil excavations in a railway tunnel imparted repeated loading on rock mass of sidewall and roof of the tunnel. The blast induced damage was assessed by using vibration attenuation equations of charge weight scaling law and measured by borehole extensometers and borehole camera. Ground vibrations of each blasting round were also monitored by triaxial geophones installed near the borehole extensometers. The peak particle velocity (V-max) observations and plastic deformations from borehole extensometers were used to develop a site specific damage model. The study reveals that repeated dynamic loading imparted on the exposed tunnel from subsequent blasts, in the vicinity, resulted in rock mass damage at lesser vibration levels than the critical peak particle velocity (V-cr). It was found that, the repeated blast loading resulted in the near-field damage due to high frequency waves and far-field damage due to low frequency waves. The far field damage, after 45-50 occurrences of blast loading, was up to 55% of the near-field damage in basaltic rock mass. The findings of the study clearly indicate that the phenomena of repeated blasting with respect to number of cycles of loading should be taken into consideration for proper assessment of blast induced damage in underground excavations.
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In the present study a two dimensional model is first developed to show the behaviour of dense non-aqueous phase liquids (DNAPL) within a rough fracture. To consider the rough fracture, the fracture is imposed with variable apertures along its plane. It is found that DNAPL follows preferential pathways. In next part of the study the above model is further extended for non-isothermal DNAPL flow and DNAPL-water interphase mass transfer phenomenon. These two models are then coupled with joint deformation due to normal stresses. The primary focus of these models is specifically to elucidate the influence of joint alteration due to external stress and fluid pressures on flow driven energy transport and interphase mass transfer. For this, it is assumed that the critical value for joint alteration is associated with external stress and average of water and DNAPL pressures in multiphase system and the temporal and spatial evolution of joint alteration are determined for its further influence on energy transport and miscible phase transfer. The developed model has been studied to show the influence of deformation on DNAPL flow. Further this preliminary study demonstrates the influence of joint deformation on heat transport and phase miscibility via multiphase flow velocities. It is seen that the temperature profile changes and shows higher diffusivity due to deformation and although the interphase miscibility value decreases but the lateral dispersion increases to a considerably higher extent.
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Students with disruptive behaviour in the Australian state of New South Wales are increasingly being educated in separate “behaviour” schools. There is however surprisingly little research on how students view these settings, or indeed the mainstream schools from which they were excluded. To better understand excluded students’ current and past educational experiences, we interviewed 33 boys, aged between 9 and 16 years of age, who were enrolled in separate special schools for students with disruptive behaviour. Analyses reveal that the majority of participants began disliking school in the early years due to difficulties with school work and teacher conflict. Interestingly, while most indicated that they preferred the behaviour school, more than half still wanted to return to their old school. It is therefore clear that separate special educational settings are not a solution to disruptive behaviour in mainstream schools. Whilst these settings do fulfil a function for some students, the preferences of the majority of boys suggest that “mainstream” school reform is of first order importance.
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Seven discrete stages and substages of moulting in the ornate rock lobster, Panulirus ornatus, have been distinguished by microscopic examination of the cuticle and setae of the pleopods . The diagnostic features and the duration of each of the stages are described. Freezing did not visually alter the tissue features used to identify each moult stage. Pleopod morphology can reliably indicate whether a lobster has moulted within the previous 24 h or is within 72 h of the next ecdysis.
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Approximately 125 prehistoric rock paintings have been found in the modern territory of Finland. The paintings were done with red ochre and are almost without exception located on steep lakeshore cliffs associated with ancient water routes. Most of the sites are found in the central and eastern parts of the country, especially on the shores of Lakes Päijänne and Saimaa. Using shore displacement chronology, the art has been dated to ca. 5000 – 1500 BC. It was thus created mainly during the Stone Age and can be associated with the so-called ‘Comb Ware’ cultures of the Subneolithic period. The range of motifs is rather limited, consisting mainly of schematic depictions of stick-figure humans, elks, boats, handprints and geometric signs. Few paintings include any evidence of narrative scenes, making their interpretation a rather difficult task. In Finnish archaeological literature, the paintings have traditionally been associated with ’sympathetic’ hunting magic, or the belief that the ritual shooting of the painted animals would increase hunting luck. Some writers have also suggested totemistic and shamanistic readings of the art. This dissertation is a critical review of the interpretations offered of Finnish rock art and an exploration of the potentials of archaeological and ethnographic research in increasing our knowledge of its meaning. Methods used include ’formal’ approaches such as archaeological excavation, landscape analysis and the application of neuropsychological research to the study of rock art, as well as ethnographically ’informed’ approaches that make use of Saami and Baltic Finnish ethnohistorical sources in interpretation. In conclusion, it is argued that although North European hunter-gatherer rock art is often thought to lie beyond the reach of ‘informed’ knowledge, the exceptional continuity of prehistoric settlement in Finland validates the informed approach in the interpretation of Finnish rock paintings. The art can be confidently associated with shamanism of the kind still practiced by the Saami of Northern Fennoscandia in the historical period. Evidence of similar shamanistic practices, concepts and cosmology are also found in traditional Finnish-Karelian epic poetry. Previous readings of the art based on ‘hunting magic’ and totemism are rejected. Most of the paintings appear to depict experiences of falling into a trance, of shamanic metamorphosis and trance journeys, and of ‘spirit helper’ beings comparable to those employed by the Saami shaman (noaidi). As demonstrated by the results of an excavation at the rock painting of Valkeisaari, the painted cliffs themselves find a close parallel in the Saami cult of the 'sieidi', or sacred cliffs and boulders worshipped as expressing a supernatural power. Like the Saami, the prehistoric inhabitants of the Finnish Lake Region seem to have believed that certain cliffs were ’alive’ and inhabited by the spirit helpers of the shaman. The rock paintings can thus be associated with shamanic vision quests, and the making of ‘art’ with an effort to socialize the other members of the community, especially the ritual specialists, with trance visions. However, the paintings were not merely to be looked at. The red ochre handprints pressed on images of elks, as well as the fact that many paintings appear ’smeared’, indicate that they were also to be touched – perhaps in order to tap into the supernatural potency inherent in the cliff and in the paintings of spirit animals.
Resumo:
Instances of morbidity amongst rock lobsters (Panulirus cygnus) arriving at factories in Western Australia (WA) have been attributed to stress during post-harvest handling. This study used discriminant analysis to determine whether physiological correlates of stress following a period of simulated post-harvest handling had any validity as predictors of future rejection or morbidity of western rock lobsters. Groups of 230 western rock lobsters were stored for 6 h in five environments (submerged/flowing sea water, submerged/re-circulating sea water, humid air, flowing sea water spray, and re-circulated sea water spray). The experiment was conducted in late spring (ambient sea water 22°C), and repeated again in early autumn (ambient sea water 26°C). After 6 h treatment, each lobster was graded for acceptability for live export, numbered, and its hemolymph was sampled. The samples were analysed for a number of physiological and health status parameters. The lobsters were then stored for a week in tanks in the live lobster factory to record mortality. The mortality of lobsters in the factory was associated with earlier deviations in hemolymph parameters as they emerged from the storage treatments. Discriminant analysis (DA) of the hemolymph assays enabled the fate of 80-90% of the lobsters to be correctly categorised within each experiment. However, functions derived from one experiment were less accurate at predicting mortality when applied to the other experiments. One of the reasons for this was the higher mortality and the more severe patho-physiological changes observed in lobsters stored in humid air or sprays at the higher temperature. The analysis identified lactate accumulation during emersion and associated physiological and hemocyte-related effects as a major correlate of mortality. Reducing these deviations, for example by submerged transport, is expected to ensure high levels of survival. None of the indicators tested predicted mortality with total accuracy. The simplest and most accurate means of comparing emersed treatments was to count the mortality afterwards.
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The use of geotextiles in coastal structures such as revetments and bund walls has become a common practice. The performance of these structures during their lifetime depends on the durability of geotextile used. During construction of these coastal structures, geotextiles are subjected to a drop load with high impact stress and that can damage the geotextile. In the current design practice, index tests are insufficient in predicting the performance of the geotextile. This puts the stability and performance of the coastal structures at risk. The current geotextile design guidelines are based on index tests and there is no standard procedure to account for the potential loss in the geotextile’s mechanical properties during installation (construction).This study aims to develop a standard procedure to estimate the properties of geotextile after its installation and using these properties for designing the performance of these structures. This paper describes the laboratory method of simulating large scale rock dumping on non-woven geotextiles and how to quantify the retained strength of damaged geotextiles. Results show that the reduction in retained strength of geotextile could extent up to 26% during installation.
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This paper reports on the collection of S. australiensis from the continental shelf off southern Queensland, easter Australia, in the western Central Pacific, documenting for the first time the occurrence of the species outside of eastern Bass Strait.
Resumo:
The contact zone and pressure distribution between two elastic plates joined by an elastic bolt and nut are estimated using finite element analysis. Smooth interfacial conditions are assumed in all the regions of contact. Eight node axisymmetric ring elements are used to model the structure. The matrix solution is obtained through frontal technique and this solution technique is shown to be very efficient for the iterative scheme adopted to determine the extent of contact. A parametric study is conducted varying the elastic properties of bolt and plate materials, bolt head diameter and thickness of the plates. The method of approach presented in this paper provides a solution with a realistic idealization of tension flange joints.