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A systematic procedure for the application of artificial neural networks to pump fault diagnosis
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Bearing fault diagnosis using multi-layer neural networks
No full textThis paper presents an investigation into bearing fault diagnosis on centrifugal pumps which can be applied to the waste water industry. After the establishment of a vibration monitoring system in a pumping station, signals were recorded regularly to build up a vibration database for future monitoring. Conventional methods were used to analyse the vibration signals and some bearing defects were successfully detected.However, the major challenge for this project was to use a vibration monitoring system to predict pump bearing faults automatically instead of by analysing the data off-line. This paper proposes a solution based on artificial neural networks (ANNs), which is a powerful technique for pattern recognition and can be applied to the classification of pump faults. Due to the long period of time required to obtain essential information from the pumping station for neural network training, a test-rig pump was established in the laboratory to simulate the common pump faults, including typical bearing defects. Bearing faults were simulated by generating pit marks on the bearings using electrical discharge machining (EDM.). Vibration signals in the time-domain were collected and pre-processed to act as the inputs to neural networks. The neural networks were then trained and their classification accuracy rates evaluated. In this study neural network models were designed using the Matlab Neural Network Toolbox and the models which successfully classified the vibration signals were chosen for pump fault diagnosis
The application of vibration analysis to pump fault diagnosis in the waste water industry
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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