In this chapter, we show how CircularTrip or ArcTrip can be used to efficiently monitor the variants of NN queries. Our CircularTrip or ArcTrip based algorithms to answer such queries preserve the following properties
To the best of our knowledge, there is no existing approach that can efficiently monitor such queries. Though CPM can be used to answer such queries, it is easy to verify that CPM is not efficient.
The rest of the chapter is organized as follows. In section , we present algorithms for constrained NN queries. We present the technique to continuously monitor farthest neighbors in Section . ( )-NN queries are discussed in Section .