122 resultados para underground mines


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Robotics in mines, aerospace, underwater, everyday unstructured environments and sensor networks with communicating devices that collect data.

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Many large coal mining operations in Australia rely heavily on the rail network to transport coal from mines to coal terminals at ports for shipment. Over the last few years, due to the fast growing demand, the coal rail network is becoming one of the worst industrial bottlenecks in Australia. As a result, this provides great incentives for pursuing better optimisation and control strategies for the operation of the whole rail transportation system under network and terminal capacity constraints. This PhD research aims to achieve a significant efficiency improvement in a coal rail network on the basis of the development of standard modelling approaches and generic solution techniques. Generally, the train scheduling problem can be modelled as a Blocking Parallel- Machine Job-Shop Scheduling (BPMJSS) problem. In a BPMJSS model for train scheduling, trains and sections respectively are synonymous with jobs and machines and an operation is regarded as the movement/traversal of a train across a section. To begin, an improved shifting bottleneck procedure algorithm combined with metaheuristics has been developed to efficiently solve the Parallel-Machine Job- Shop Scheduling (PMJSS) problems without the blocking conditions. Due to the lack of buffer space, the real-life train scheduling should consider blocking or hold-while-wait constraints, which means that a track section cannot release and must hold a train until the next section on the routing becomes available. As a consequence, the problem has been considered as BPMJSS with the blocking conditions. To develop efficient solution techniques for BPMJSS, extensive studies on the nonclassical scheduling problems regarding the various buffer conditions (i.e. blocking, no-wait, limited-buffer, unlimited-buffer and combined-buffer) have been done. In this procedure, an alternative graph as an extension of the classical disjunctive graph is developed and specially designed for the non-classical scheduling problems such as the blocking flow-shop scheduling (BFSS), no-wait flow-shop scheduling (NWFSS), and blocking job-shop scheduling (BJSS) problems. By exploring the blocking characteristics based on the alternative graph, a new algorithm called the topological-sequence algorithm is developed for solving the non-classical scheduling problems. To indicate the preeminence of the proposed algorithm, we compare it with two known algorithms (i.e. Recursive Procedure and Directed Graph) in the literature. Moreover, we define a new type of non-classical scheduling problem, called combined-buffer flow-shop scheduling (CBFSS), which covers four extreme cases: the classical FSS (FSS) with infinite buffer, the blocking FSS (BFSS) with no buffer, the no-wait FSS (NWFSS) and the limited-buffer FSS (LBFSS). After exploring the structural properties of CBFSS, we propose an innovative constructive algorithm named the LK algorithm to construct the feasible CBFSS schedule. Detailed numerical illustrations for the various cases are presented and analysed. By adjusting only the attributes in the data input, the proposed LK algorithm is generic and enables the construction of the feasible schedules for many types of non-classical scheduling problems with different buffer constraints. Inspired by the shifting bottleneck procedure algorithm for PMJSS and characteristic analysis based on the alternative graph for non-classical scheduling problems, a new constructive algorithm called the Feasibility Satisfaction Procedure (FSP) is proposed to obtain the feasible BPMJSS solution. A real-world train scheduling case is used for illustrating and comparing the PMJSS and BPMJSS models. Some real-life applications including considering the train length, upgrading the track sections, accelerating a tardy train and changing the bottleneck sections are discussed. Furthermore, the BPMJSS model is generalised to be a No-Wait Blocking Parallel- Machine Job-Shop Scheduling (NWBPMJSS) problem for scheduling the trains with priorities, in which prioritised trains such as express passenger trains are considered simultaneously with non-prioritised trains such as freight trains. In this case, no-wait conditions, which are more restrictive constraints than blocking constraints, arise when considering the prioritised trains that should traverse continuously without any interruption or any unplanned pauses because of the high cost of waiting during travel. In comparison, non-prioritised trains are allowed to enter the next section immediately if possible or to remain in a section until the next section on the routing becomes available. Based on the FSP algorithm, a more generic algorithm called the SE algorithm is developed to solve a class of train scheduling problems in terms of different conditions in train scheduling environments. To construct the feasible train schedule, the proposed SE algorithm consists of many individual modules including the feasibility-satisfaction procedure, time-determination procedure, tune-up procedure and conflict-resolve procedure algorithms. To find a good train schedule, a two-stage hybrid heuristic algorithm called the SE-BIH algorithm is developed by combining the constructive heuristic (i.e. the SE algorithm) and the local-search heuristic (i.e. the Best-Insertion- Heuristic algorithm). To optimise the train schedule, a three-stage algorithm called the SE-BIH-TS algorithm is developed by combining the tabu search (TS) metaheuristic with the SE-BIH algorithm. Finally, a case study is performed for a complex real-world coal rail network under network and terminal capacity constraints. The computational results validate that the proposed methodology would be very promising because it can be applied as a fundamental tool for modelling and solving many real-world scheduling problems.

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The late French philosopher Gilles Deleuze has enjoyed significant notoriety and acclaim in American academia over the last 20 years. The unique disciplinary focus of the contemporary discussion has derived from Deleuze the architectural possibilities of biotechnology, systems theory, and digital processualism. While the persistence of Deleuze’s theory of science and the formalist readings of Mille Plateaux and Le Bergsonisme have dominated the reception since the 1990s, few are aware of a much earlier encounter between Deleuze and architects, beginning at Columbia University in the 1970s, which converged on the radical politics of Anti-OEdipus and its American reception in the journal Semiotext(e), through which architecture engaged a much broader discourse alongside artists, musicians, filmmakers, and intellectuals in the New York aesthetic underground, of which Deleuze and Félix Guattari were themselves a part.

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Groundwater from Maramarua has been identified as coal seam gas (CSG) water by studying its composition, and comparing it against the geochemical signature from other CSG basins. CSG is natural gas that has been produced through thermogenic and biogenic processes in underground coal seams; CSG extraction requires the abstraction of significant amounts of CSG water. To date, no international literature has described coal seam gas water in New Zealand, however recent CSG exploration work has resulted in CSG water quality data from a coal seam in Maramarua, New Zealand. Water quality from this site closely follows the geochemical signature associated with United States CSG waters, and this has helped to characterise the type of water being abstracted. CSG water from this part of Maramarua has low calcium, magnesium, and sulphate concentrations but high sodium (334 mg/l), chloride (146 mg/l) and bicarbonate (435 mg/l) concentrations. In addition, this water has high pH (7.8) and alkalinity (360 mg/l as CaCO3), which is a direct consequence of carbonate dissolution and biogenic processes. Different analyte ratios ('source-rock deduction' method) have helped to identify the different formation processes responsible in shaping Maramarua CSG water

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This is the first in a series of four articles which will explore different aspects of air pollution, its impact on health and challenges in defining the boundaries between impact and nonimpact on health. Hardly a new topic one might say. Indeed, it’s been an issue for centuries, millennia even! For example, Pliny the Elder (AD 23-79), a Roman officer and author of the ‘Natural History’ recommended that: “…quarry slaves from asbestos mines not be purchased because they die young”, and suggested: “…the use of a respirator, made of transparent bladder skin, to protect workers from asbestos dust.” Closer to modern times, a Danish Proverb states: "Fresh air impoverishes the doctor". While none of these statements are an air quality guideline in a modern sense, they do illustrate that, for a very long time, we have known that there is a link between air quality and health, and that some measures were taken to reduce the impact of the exposure to the pollutants. Obviously, we are much more sophisticated now!

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The Sascha-Pelligrini low-sulphidation epithermal system is located on the western edge of the Deseado Massif, Santa Cruz Province, Argentina. Outcrop sampling has returned values of up to 160g/t gold and 796g/t silver, with Mirasol Resources and Coeur D.Alene Mines currently exploring the property. Detailed mapping of the volcanic stratigraphy has defined three units that comprise the middle Jurassic Chon Aike Formation and two units that comprise the upper Jurassic La Matilde Formation. The Chon Aike Formation consists of rhyodacite ignimbrites and tuffs, with the La Matilde Formation including rhyolite ash and lithic tuffs. The volcanic sequence is intruded by a large flow-banded rhyolite dome, with small, spatially restricted granodiorite dykes and sills cropping out across the study area. ASTER multispectral mineral mapping, combined with PIMA (Portable Infrared Mineral Analyser) and XRD (X-ray diffraction) analysis defines an alteration pattern that zones from laumontite-montmorillonite, to illite-pyritechlorite, followed by a quartz-illite-smectite-pyrite-adularia vein selvage. Supergene kaolinite and steam-heated acid-sulphate kaolinite-alunite-opal alteration horizons crop out along the Sascha Vein trend and Pelligrini respectively. Paragenetically, epithermal veining varies from chalcedonic to saccharoidal with minor bladed textures, colloform/crustiform-banded with visible electrum and acanthite, crustiform-banded grey chalcedonic to jasperoidal with fine pyrite, and crystalline comb quartz. Geothermometry of mineralised veins constrains formation temperatures from 174.8 to 205.1¡ÆC and correlates with the stability field for the interstratified illite-smectite vein selvage. Vein morphology, mineralogy and associated alteration are controlled by host rock rheology, permeability, and depth of the palaeo-water table. Mineralisation within ginguro banded veins resulted from fluctuating fluid pH associated with selenide-rich magmatic pulses, pressure release boiling and wall-rock silicate buffering. The study of the Sascha-Pelligrini epithermal system will form the basis for a deposit-specific model helping to clarify the current understanding of epithermal deposits, and may serve as a template for exploration of similar epithermal deposits throughout Santa Cruz.

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This paper introduces Sapporo World Window (hereafter SWW), an interactive social media mash-up deployed in a newly built urban public underground space utilising ten public displays and urban dwellers’ mobile phones. SWW enables users to share their favourite locations with fellow citizens and visitors through integrating various social media contents to a coherent whole. The system aims to engage citizens in socio-cultural and technological interactions, turning the underground space into a creative and lively social space. We present first insight from an initial user study in a real world setting.

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The ability to play freely in our cities is essential for sustainable wellbeing. When integrated successfully into our cities, Urban Play performs an important role; physically, socially and culturally contributing to the image of the city. While Urban Play is essential, it also finds itself in conflict with the city. Under modernist urban approaches play activities have become progressively segregated from the urban context through a tripartite of design, procurement and management practices. Despite these restrictions, emergent underground play forms overcome the isolation of play within urban space. One of these activities (parkour) is used as an evocative case study to reveal the hidden urban terrains of desire and fear as it re-interprets the fabric of the city, eliciting practice based discussions about procurement, design and management practice along its route.

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Chinese independent cinema has developed for more than twenty years. Two sorts of independent cinema exist in China. One is underground cinema, which is produced without official approvals and cannot be circulated in China, and the other are the films which are legally produced by small private film companies and circulated in the domestic film market. This sort of ‘within-system’ independent cinema has played a significant role in the development of Chinese cinema in terms of culture, economics and ideology. In contrast to the amount of comment on underground filmmaking in China, the significance of ‘within-system’ independent cinema has been underestimated by most scholars. This thesis is a study of how political management has determined the development of Chinese independent cinema and how Chinese independent cinema has developed during its various historical trajectories. This study takes media economics as the research approach, and its major methods utilise archive analysis and interviews. The thesis begins with a general review of the definition and business of American independent cinema. Then, after a literature review of Chinese independent cinema, it identifies significant gaps in previous studies and reviews issues of traditional definition and suggests a new definition. After several case studies on the changes in the most famous Chinese directors’ careers, the thesis shows that state studios and private film companies are two essential domestic backers for filmmaking in China. After that, the body of the thesis provides an examination of the development of ‘within-system’ independent cinema. Specifically, three factors: government intervention, the majors’ performance (state studios and, later, the conglomerates) and the market conduct of independent cinema at various points in their trajectories are studied. The key findings of the study are as follows: First, most scholars have overlooked the existence and the significance of within-system Chinese independent cinema. Drawing on an American definition of the independent sector, this thesis proposes a definition of the sector in China: namely, any film that has not been financed, produced, and/or distributed by majors. The thesis also notes important contradictions in applying this definition: i.e. film-making is still dependent on policies that frame industry development. The thesis recognises that major tensions apply to filmmaking in China, which significantly differentiates the Chinese independents from those in the US. Second, the development of Chinese independent cinema is the result the rise of the private sector and the decline of the state studio system. As state studios encountered difficulties the private sector moved forward; consequently the environment improved for independent cinema. Third, before 2003, the film industry in China had little commercialisation. The government controlled independent cinema by means of license and censorship. State studios produced main melody films and Hollywood attracted most of the audiences. Many independent filmmakers focused on commercial films, thus contributing to film commercialisation. Fourth, after 2003, the film industry became increasingly fragmented. The government created distribution and exhibition opportunities for main melody films; conglomerates collaborated with Hong Kong players; Hong Kong co-productions and Hollywood occupied the film market; and small private film companies produced main melody films in order to earn meagre profits. The original contribution of the thesis is to advance the study of Chinese independent cinema. The study suggests a reasonable and practical definition of Chinese independent cinema. It shows how the Chinese government authorities have implemented economic measures to gain ideological control in the film industry. Finally, this the first study on Chinese independent cinema applying a synthesis of economic, political and historical perspectives.

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This study examines a dialogue process managers can use to explore community attitudes. The objectives of the research are to develop a dialogue process that engages community audiences on climate mitigation strategies. Secondly, to understand participants perspectives and potential reactions in particular to underground storage of CO2 and determine the strategies that most effectively engage people in dialogue to enable the climate change debate to move forward. Finally, to develop a dialogue process that can be used by managers on other politically sensitive topics. Knowledge of the dynamics of psychosocial relationships and communication between stakeholders contributed to increased understanding of the issues. The key findings of this study indicate that the public can be engaged in dialogue on the issue of CO2 capture and storage and low emission technologies without engendering adverse reactions. The dialogue process is critical to participant’s engagement and led to behaviour change in energy use.

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This chapter describes how, as YouTube has scaled up both as a platform and as a company, its business model and the consequences for its copyright regulation strategies have co-evolved, and so too the boundaries between amateur and professional media have shifted and blurred in particular ways. As YouTube, Inc moves to more profitably arrange and stabilise the historically contentious relations among rights-holders, uploaders, advertisers and audiences, some forms of amateur video production have become institutionalised and professionalised, while others have been further marginalised and driven underground or to other, more forgiving, platforms.