55,572 research outputs found

    Unsupervised Text Extraction from G-Maps

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    This paper represents an text extraction method from Google maps, GIS maps/images. Due to an unsupervised approach there is no requirement of any prior knowledge or training set about the textual and non-textual parts. Fuzzy CMeans clustering technique is used for image segmentation and Prewitt method is used to detect the edges. Connected component analysis and gridding technique enhance the correctness of the results. The proposed method reaches 98.5% accuracy level on the basis of experimental data sets.Comment: Proc. IEEE Conf. #30853, International Conference on Human Computer Interactions (ICHCI'13), Chennai, India, 23-24 Aug., 201

    Quantification of the performance of iterative and non-iterative computational methods of locating partial discharges using RF measurement techniques

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    Partial discharge (PD) is an electrical discharge phenomenon that occurs when the insulation materialof high voltage equipment is subjected to high electric field stress. Its occurrence can be an indication ofincipient failure within power equipment such as power transformers, underground transmission cableor switchgear. Radio frequency measurement methods can be used to detect and locate discharge sourcesby measuring the propagated electromagnetic wave arising as a result of ionic charge acceleration. Anarray of at least four receiving antennas may be employed to detect any radiated discharge signals, thenthe three dimensional position of the discharge source can be calculated using different algorithms. These algorithms fall into two categories; iterative or non-iterative. This paper evaluates, through simulation, the location performance of an iterative method (the standardleast squares method) and a non-iterative method (the Bancroft algorithm). Simulations were carried outusing (i) a "Y" shaped antenna array and (ii) a square shaped antenna array, each consisting of a four-antennas. The results show that PD location accuracy is influenced by the algorithm's error bound, thenumber of iterations and the initial values for the iterative algorithms, as well as the antenna arrangement for both the non-iterative and iterative algorithms. Furthermore, this research proposes a novel approachfor selecting adequate error bounds and number of iterations using results of the non-iterative method, thus solving some of the iterative method dependencies

    Providing equivalent learning activities with software-based remote access laboratories

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    Laboratory-based learning activities are important components of engineering and surveying education and it is difficult to offering practical activities to distance education students. Remote Access Laboratory (RAL) systems are widely discussed as learning tools to offer students remote access to rigs or hardware. In some disciplines laboratory activities are purely software based and RAL systems can be used to provide access to software. As part of a larger study into the transferability of the remote laboratory concept to non-engineering disciplines this project evaluates the effectiveness of RAL based software activities in supporting student learning is investigated. In the discipline of Surveying and Spatial Science, RAL technology is used to provide Geographic Information System software access to distance students. The key research question discussed in this paper is whether RALbased software activities can address the same learning outcomes as face-to-face practical classes for software activities. Data was collected from students' discussion forums, teaching staff diaries and teaching staff interviews. The project demonstrates that students undertaking learning activities remotely achieve similar learning outcomes than student in practice classes using the same software. Ease of system access and usability are critical and the learning activity needs to be supported by comprehensive learning materials. This research provides a clear case in which the use of RAL technology has provided inclusive educational opportunities more efficiently and these general results are also applicable to experiments that involve physical hardware

    Database Engines for Geographical Information Systems

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    Our ability to identify, acquire, store, enquire on and analyse data is increasing as never before, especially in the GIS field. Technologies are becoming available to manage a wider variety of data and to make intelligent inferences on that data. The mainstream arrival of large-scale database engines is not far away. The experience of using the first such products tells us that they will radically change data management in the GIS field
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