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This thesis presents the results of research into the potential of underground mining methods applicable to inclined thick seams (thickness greater than 3.5m, and seam dip of 15 - 35 degree) in the Quangninh coalfield, Vietnam. The primary objectives of this research are to investigate the most suitable underground methods applicable to inclined thick seams in the Quangninh coalfield and to improve understanding of the operational and geotechnical issues associated with the application of chosen methods in thick seams with steeply dipping conditions. From a risk and operational assessment, the Longwall Top Coal Caving (LTCC) method is considered most appropriate for inclined thick seams under the current mining conditions in Vietnam. The LTCC method offers great potential for the efficient extraction of thick seams by caving coal from the upper section during the mining of the lower section. This significantly reduces the development cost per tonne. Compared to High reach Single Pass Longwalling, the LTCC method offers a low extraction height, resulting in smaller and less expensive equipment and better face conditions. Results from this study identified that for extracting an inclined thick seam, the face retreating along the strike has better operational advantages and better cavability than the face retreating updip or downdip of the seam. The operational issues of the LTCC method when extracting inclined seams are: the stability of the support, transport in the mine, and the difficulties in roof control at the transition between face ends and the gateroads. In terms of geotechnical issues, better cavability of the top coal is anticipated for flat coal seams compared to inclined seams. In addition, the chain pillar for flat coal seams is subjected to a higher vertical stress distribution than that of inclined ones. An improved cavability assessment method for the categorisation of the cavability of the top coal with four categories, ranging from 1 (excellent cavability) to 4 (very poor cavability), was suggested to assist the feasibility and design stages of the LTCC application. The cavability assessment method was conducted by numerical analysis combined with back analysis from the database obtained from past LTCC practices.

This thesis presents the results of research into the potential of underground mining methods applicable to inclined thick seams (thickness greater than 3.5m, and seam dip of 15 - 35 degree) in the Quangninh coalfield, Vietnam. The primary objectives of this research are to investigate the most suitable underground methods applicable to inclined thick seams in the Quangninh coalfield and to improve understanding of the operational and geotechnical issues associated with the application of chosen methods in thick seams with steeply dipping conditions. From a risk and operational assessment, the Longwall Top Coal Caving (LTCC) method is considered most appropriate for inclined thick seams under the current mining conditions in Vietnam. The LTCC method offers great potential for the efficient extraction of thick seams by caving coal from the upper section during the mining of the lower section. This significantly reduces the development cost per tonne. Compared to High reach Single Pass Longwalling, the LTCC method offers a low extraction height, resulting in smaller and less expensive equipment and better face conditions. Results from this study identified that for extracting an inclined thick seam, the face retreating along the strike has better operational advantages and better cavability than the face retreating updip or downdip of the seam. The operational issues of the LTCC method when extracting inclined seams are: the stability of the support, transport in the mine, and the difficulties in roof control at the transition between face ends and the gateroads. In terms of geotechnical issues, better cavability of the top coal is anticipated for flat coal seams compared to inclined seams. In addition, the chain pillar for flat coal seams is subjected to a higher vertical stress distribution than that of inclined ones. An improved cavability assessment method for the categorisation of the cavability of the top coal with four categories, ranging from 1 (excellent cavability) to 4 (very poor cavability), was suggested to assist the feasibility and design stages of the LTCC application. The cavability assessment method was conducted by numerical analysis combined with back analysis from the database obtained from past LTCC practices.

Post-Stack inversion of reflection data in seismic exploration can be used to obtain detailed information about lithology variations in the zone of interest. Generalized Linear Inversion (GLI) has previously been applied as a useful tool to achieve this. The purpose of my investigation is to apply GLI to data from the Coal Measures. It is known that in the Coal Measures the most strongly reflecting horizons are the coal seams, which are the exploration targets. In the seismic bandwidth they are thin beds, which causes particular problems associated with vertical resolution for the inversion. The method is applied to a seismic line from the Belvoir Coalfield supplied by British Coal. In order to get better relative amplitudes and to keep the same bandwidth down the whole section, the data were carefully reprocessed using the ProMAX software. Wireline log data from two boreholes intersected by the seismic line were edited to generate acoustic impedance logs as functions of time. Software was developed to implement GLI, and tested on synthetic data before applying it to the reprocessed data. The initial guesses for earth and wavelet models at the boreholes were obtained after systematic studies to determine the best strategy. The construction of the initial guess for the boundary locations elsewhere on the section is very critical for the success of the search for the global minimum. A combination of structural interpretation and the inversion results obtained from the previous trace was found to do the best job. I have tried to invert separately for the boundary locations, acoustic impedances and the wavelet, with the wavelet parameterized in the frequency domain. I found that, provided that the wavelet extracted at a borehole is a good estimate with low error energy, the most successful strategy is just to invert for the boundary locations, keeping the acoustic impedances and the extracted wavelet fixed. If the extracted wavelet is not a good estimate, then parameterizing the wavelet in the frequency domain and optimizing those parameters at the borehole is a useful approach. None of the implemented inversion strategies produced a perfect result. Discrepancies were due to the difficulty in obtaining true relative amplitude values on the processed section. The inversion results and systematic studies on the field dataset indicate that the assumptions of the convolutional model are not satisfied by the processed section.

A survey of robotized seam-tracking techniques was conducted in preparation for a project consisting of using an infrared camera on a robot for on one side collect continuous weld images for NDT inspection and on the other one track the weld joint. The tracking system can be used to discover the position of the weld bead without previous information. The robust system is outlined, along with its merits and disadvantages.

Regulation in its generic sense has existed for a very long time in different forms, with different aims and different problems of accountability, but the study of competition regulation by a Government agency has perhaps become fashionable only in recent years. This thesis consists of two leading themes. First, it will contend that, whilst the market system has been seriously underestimated as a social institution to the extent that it should be left to operate and organise itself where that is possible, it is at the same time not always self-regulating. Residual intervention by the State or its agencies will remain necessary in strategic cases, either to protect individual autonomy and choice, or to correct failures of the market system. The question is simply more or less regulation. Secondly, and on that premise, competition regulation must be distinguished into economic regulation and antitrust regulation because the relationship between them is inversely proportional: the more intense economic regulation is, the less important antitrust regulation becomes. By implication then, economic liberalisation or deregulation must be accompanied by a robust framework of antitrust regulation to ensure that the conditions of sustainable competition are not threatened by anti-competitive practices. Conditions of sustainable competition are thus critical for market contestability. For many years, domestic and international airline competition has been the subject of comprehensive regulation. With the passage of time, however, the thinking has changed and, no doubt, liberal policies and practices will continue to find expression in future political and economic sentiments. The responsibility for regulating airlines in the United Kingdom falls on the Civil Aviation Authority, which has played a formidable role in transforming the policy of heavy regulation into minimal regulation, although much of that regulatory landscape has now been altered with the advent of the Single European Aviation Market. The experiences of, both, the CAA and the new SEATNI provide an illuminating account of the evolutionary process of regulating airline competition, that from economic to antitrust regulation.

Supervised deep neural networks have been successfully applied to many real-world measurement applications. However, their success relies on labeled data which is expensive and time-consuming to obtain, especially when domain expertise is required. For this reason, researchers have turned to semi-supervised learning for image classification tasks. Semi-supervised learning uses structural assumptions to automatically leverage unlabeled data, dramatically reducing manual labeling efforts. We conduct our research based on images from Enclosures Direct Inc. (EDI) which is a manufacturer of enclosures used to house and protect electronic devices. Their industrial robotics utilizes a computer vision system to guide a robot in a welding application employing a laser and a camera. The laser is combined with an optical line generator to cast a line of structured light across a joint to be welded. An image of the structured light is captured by the camera which needs to be located in the image in order to find the desired coordinate for the weld seam. The existing system failed due to the fact that the traditional machine vision algorithm cannot analyze the image correctly in unexpected imaging conditions or during variations in the manufacturing process. In this thesis, we purpose a novel algorithm for semi-supervised key-point detection for seam placement by a welding robot. Our deep learning based algorithm overcomes unfavorable imaging conditions providing faster and more precise predictions. Moreover, we demonstrate that our approach can work with as few as ten labeled images accepting a reduction of detection accuracy. In addition, we also purpose a method that can utilize full image resolution to enhance the accuracy of the key-point detection.

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A large percentage of Southern Appalachian coal reserves are located in seams less than 36" thick. As thicker and currently more mineable, deposits are exhausted, methods of underground thin-seam extraction will have to be developed. These methods must be capable of removing coal efficiently and economically. Past experience with highwall mining of thin-seam coal has indicated that recovery rates tend to be lower than in conventional operations. It is suspected that this will also apply to underground thin-seam mining, regardless of proposed technology or mining method. A method of increasing recoveries from thin-seam mining operations is necessary in order to exploit thin-seam reserves. Backfilling is one alternative that may find applicability in thin-seam coal mining. The ability of backfill to provide additional ground support may enhance coal recovery by allowing for the design of undersized pillars. Backfill has been used extensively in hard rock mining but has found limited use in coal mining. Its adaptability to thin-seam coal mining has been examined and is presented in this thesis. Backfill is capable of providing additional ground support by restricting lateral deformation of surrounding coal pillars and roof. This additional support can result in significant increases in recovery from thin-seam coal deposits. However, the overall feasibility of backfill is dependent on the in situ behavior of the fill material, the properties of the fill, the effects of the filling method on the total mining operation, and the cost of filling per extra ton of coal recovered. The influence of these parameters has been studied and indicate that, in certain situations, backfilling for the purpose of increasing recovery rates from thin-seam coal mines is feasible. / Master of Science