@InProceedings{TanakaVieiKast:2015:EfAlDi,
author = "Tanaka, Pedro Sena and Vieira, Marcos R. and Kaster, Daniel S.",
affiliation = "{Universidade Estadual de Londrina (UEL)} and {Big Data Research
Lab} and {Universidade Estadual de Londrina (UEL)}",
title = "Efficient algorithms to discover flock patterns in trajectories",
booktitle = "Anais...",
year = "2015",
editor = "Fileto, Renato and Korting, Thales Sehn",
organization = "Simp{\'o}sio Brasileiro de Geoinform{\'a}tica, 16. (GEOINFO)",
publisher = "Instituto Nacional de Pesquisas Espaciais (INPE)",
address = "S{\~a}o Jos{\'e} dos Campos",
abstract = "With the ubiquitous use of location enabled devices, pattern
discovery in trajectories has been receiving increasing interest.
Among such patterns, we have queries related to how groups of
moving objects behave over time such as discovering flocks. A
flock pattern is defined as a set of moving objects that move
within a predefined distance to each other for a given continuous
period of time. A typical application example is surveillance,
where relies on discovering flocks on very large streaming
spatiotemporal data efficiently. Previous work presented a
polynomial solution to the problem of finding flocks with fixed
time duration. And presented as well a set of algorithms based on
this solution, which are the state-of-the-art algorithms regarding
this problem. In this paper, we improve those algorithms by
applying the plane sweeping technique in conjunction to an
inverted index. The plane sweeping accelerates the detection of
groups of objects that are candidates to be a flock in a time
instant and the inverted index is used to compare candidate disks
across time instants quickly. Using an assortment of real-world
trajectory datasets, we show that our proposed methods are very
efficient. When compared with the baseline flock algorithm, our
proposed methods achieved up to 46x speedup reducing the elapsed
time from thousands of seconds to milliseconds.",
conference-location = "Campos do Jord{\~a}o, SP",
conference-year = "27 nov. a 02 dez.",
language = "en",
ibi = "8JMKD3MGP3W34R/42GRPC2",
url = "http://urlib.net/ibi/8JMKD3MGP3W34R/42GRPC2",
targetfile = "tanaka_efficient1.pdf",
urlaccessdate = "28 abr. 2024"
}