Also, to
design a distributed edge detection scheme based on the dual-space transform
is another challenge.
4 Distributed Edge Detection
In an application of sensor detection, it is very hard to identify an event simply
using the information gathered at one node. Instead, the presence of an event
might be better described by a wide range of spatial regions where multiple
sensors are deployed. To some extent, boundary estimation is considered a
promising solution to the distributed spatial tracking problem.
A sensor node can determine whether it is on the boundary or not based on
the information collected from its neighboring nodes. Usually, in a contiguous
area, if some nodes observe the same phenomenon, they are considered to be
in the same region. But in some other cases, it is not always true. Consider
the scenario in Figure 12, where nodes A,B and their neighbors observe the
same event E, but they belong to di?®erent regions. Thus, we need a distributed
computation to distinguish the boundary.
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Ren-Shiou Liu, Lifeng Sang, and Prasun Sinha
Fig. 12. Same event E detected by both nodes A and B from di?®erent regions.
4.1 Overview
In distributed region detection, the goal is to determine a set of distributed
point sensors that observe a similar phenomenon in a contiguous area, where
the computation is processed in a distributed manner. A 2-dimensional freeform
line connecting the sensors that detect similar events can be nearly
considered a boundary in a certain region.
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