A Time-Position Join Method for Periodicity Mining in Time Series Databases

2016 ◽  
Author(s):  
Chia-En Li ◽  
Ye-In Chang
Keyword(s):  
Time Series ◽  
Time Position ◽  
Periodicity Mining

Efficient Periodicity Mining in Time Series Databases Using Suffix Trees

2011 ◽  
Vol 23 (1) ◽  
pp. 79-94 ◽  
Author(s):  
Faras Rasheed ◽  
Mohammed Alshalalfa ◽  
Reda Alhajj
Keyword(s):  
Time Series ◽  
Suffix Trees ◽  
Periodicity Mining

scholarly journals Learning towards Abstractive Timeline Summarization

2019 ◽  
Author(s):  
Xiuying Chen ◽  
Zhangming Chan ◽  
Shen Gao ◽  
Meng-Hsuan Yu ◽  
Dongyan Zhao ◽  
...  
Keyword(s):  
Time Series ◽  
Real World ◽  
Large Scale ◽  
State Of The Art ◽  
Event Memory ◽  
Document Summarization ◽  
Word Level ◽  
Level Information ◽  
Time Position ◽  
Evolution Trajectory

Timeline summarization targets at concisely summarizing the evolution trajectory along the timeline and existing timeline summarization approaches are all based on extractive methods.In this paper, we propose the task of abstractive timeline summarization, which tends to concisely paraphrase the information in the time-stamped events.Unlike traditional document summarization, timeline summarization needs to model the time series information of the input events and summarize important events in chronological order.To tackle this challenge, we propose a memory-based timeline summarization model (MTS).Concretely, we propose a time-event memory to establish a timeline, and use the time position of events on this timeline to guide generation process.Besides, in each decoding step, we incorporate event-level information into word-level attention to avoid confusion between events.Extensive experiments are conducted on a large-scale real-world dataset, and the results show that MTS achieves the state-of-the-art performance in terms of both automatic and human evaluations.

The LDE-Type Flare Occurrence (1969-1993)

1994 ◽  
Vol 144 ◽  
pp. 279-282
Author(s):  
A. Antalová
Keyword(s):  
Time Series ◽  
Fourier Analysis ◽  
Sunspot Cycle ◽  
List Type ◽  
Type Number ◽  
Solar Cycles ◽  
Type Iv ◽  
Long Duration ◽  
Cycle Maximum ◽  
Flare Index

AbstractThe occurrence of LDE-type flares in the last three cycles has been investigated. The Fourier analysis spectrum was calculated for the time series of the LDE-type flare occurrence during the 20-th, the 21-st and the rising part of the 22-nd cycle. LDE-type flares (Long Duration Events in SXR) are associated with the interplanetary protons (SEP and STIP as well), energized coronal archs and radio type IV emission. Generally, in all the cycles considered, LDE-type flares mainly originated during a 6-year interval of the respective cycle (2 years before and 4 years after the sunspot cycle maximum). The following significant periodicities were found:• in the 20-th cycle: 1.4, 2.1, 2.9, 4.0, 10.7 and 54.2 of month,• in the 21-st cycle: 1.2, 1.6, 2.8, 4.9, 7.8 and 44.5 of month,• in the 22-nd cycle, till March 1992: 1.4, 1.8, 2.4, 7.2, 8.7, 11.8 and 29.1 of month,• in all interval (1969-1992):a)the longer periodicities: 232.1, 121.1 (the dominant at 10.1 of year), 80.7, 61.9 and 25.6 of month,b)the shorter periodicities: 4.7, 5.0, 6.8, 7.9, 9.1, 15.8 and 20.4 of month.Fourier analysis of the LDE-type flare index (FI) yields significant peaks at 2.3 - 2.9 months and 4.2 - 4.9 months. These short periodicities correspond remarkably in the all three last solar cycles. The larger periodicities are different in respective cycles.

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