13 research outputs found
Interactive Mining of Strong Friends from Social Networks and Its Applications in E-Commerce
A data mining approach for machine fault diagnosis based on associated frequency patterns
Bearings play a crucial role in rotational machines and their failure is one of the foremost causes of breakdowns in rotary machinery. Their functionality is directly relevant to the operational performance, service life and efficiency of these machines. Therefore, bearing fault identification is very significant. The accuracy of fault or anomaly detection by the current techniques is not adequate. We propose a data mining-based framework for fault identification and anomaly detection from machine vibration data. In this framework, to capture the useful knowledge from the vibration data stream (VDS), we first pre-process the data using Fast Fourier Transform (FFT) to extract the frequency signature and then build a compact tree called SAFP-tree (sliding window associated frequency pattern tree), and propose a mining algorithm called SAFP. Our SAFP algorithm can mine associated frequency patterns (i.e., fault frequency signatures) in the current window of VDS and use them to identify faults in the bearing data. Finally, SAFP is further enhanced to SAFP-AD for anomaly detection by determining the normal behavior measure (NBM) from the extracted frequency patterns. The results show that our technique is very efficient in identifying faults and detecting anomalies over VDS and can be used for remote machine health diagnosis. © 2016, Springer Science+Business Media New York
Efficient frequent itemset mining from dense data streams
Due to advances in technology, high volumes of valuable data can be produced at high velocity in many real-life applications. Hence, efficient data mining techniques for discovering implicit, previously unknown, and potentially useful frequent itemsets from data streams are in demand. Many existing stream mining algorithms capture important stream data and assume that the captured data can fit into main memory. However, problems arise when the available memory is so limited that such an assumption does not hold. In this paper, we present a data structure to capture important data from the streams onto the disk. In addition, we present two algorithms-which use this data structure-to mine frequent itemsets from these dense (or sparse) data streams