## Fourier-Transform Based Techniques in Efficient Retrieval of Similar Time Sequences (1999)

Citations: | 6 - 1 self |

### BibTeX

@MISC{Rafiei99fourier-transformbased,

author = {Davood Rafiei},

title = {Fourier-Transform Based Techniques in Efficient Retrieval of Similar Time Sequences},

year = {1999}

}

### OpenURL

### Abstract

The idea of posing queries in terms of similarity of objects, rather than equality or inequality, is of growing importance in new database applications, such as data mining or data warehousing. In this dissertation, the notion of similarity is defined in terms of a distance function and a set of linear transformations. This turns out to be a proper notion of similarity for time series data since it can eliminate seasonal effects and shortterm fluctuations before aligning them. The focus of this dissertation is on efficiently processing similarity queries on time series data. The dissertation first describes an important property of real-valued time sequences in the frequency domain, i.e. symmetry, and presents an algorithm that uses this property to improve the performance of a multidimensional i...