Query operations for moving objects database systems Jose´ Moreira
Cristina Ribeiro
Talel Abdessalem
Computer Science Department Universidade Portucalense Portugal
Department of Electrical Engineering and Computing FEUP Portugal
Computer Science Department ENST de Paris France
[email protected]
[email protected]
[email protected]
ABSTRACT
!
" #
Categories and Subject Descriptors
$%& ' () * +
, $%- ' () . #
+ Keywords
! ! ! 1.
INTRODUCTION
/
! ! ! ! ! ! 0 #
) ! " , ! ! ! !
! 1 2 3 ! 4 0 % 1 & 0 5 6 7 2. MOVEMENT ISSUES
! 8! ! 9 0 " *
" : " !
b ... p 0
p1
a
p2
...
c
! ! ;
2.1 Bounding uncertainty
! ! ' = > ! # ! > = > =! " ?" %@ r2
r1 p1
L
d
p2
# !
"
':%( A ) ! ! ?B &@ ) > ? @ %! > % > B 5 > ? @
rb
L ab
ra p1
d
p2
!
! " " * 2.2 Semantics
. ! ! ! " $ ! 1 2.2.1 Possibly Semantics
2 " # " C2 # 9C! ! C ; # 9C! ; # 9 " 2.2.2 Surely Semantics
2 " " #
C2 # 9C! # 9 C ; # 9C! ; # 9 ; # 9 1 8
!
2.2.3 Probably Semantics
# ! " !
; " # 3.
MOVEMENT OPERATIONS
! " ! " ) > , > , > ! 2 " " # " > B " " ' " C8J:C " ! ! $ * / &:! %JJJ! :J)JJ#/ . ,, / . !"#0$#%!!!$!!! !! &'( .-
" ! " "
/ &:! %JJJ! :J)JJ#/ 4 "
" " $ #
. ,1 . ,2 &'( . )& ,1 . ,2 -
"
8 ?@ " ! " " $ # " " & . &'( . )& * +32 + 45 2 1 . -
; " # ?@ " $ * " J% C8J:C / %-! %JJJ &'( )& 45 45
. . . * +,!$+ * . , )5 52 . !"#%6#%!!!!"#%7#%!!! 52 !"#%6#%!!!!"#%7#%!!!! %-
" " C8J:C C8J:C B ! C8J:C " ! / %-! %JJJ! C8J:C J% 8 ?@ " ) " C8J:C "! " J% C8J:C $ C8J:C C C / &:! %JJJ , / 2 52 . !"#0$#%!!! !8#!$#%!!! &'( . )& . * +,!$+ 45 * ++-
" C8J:C C C 8J: / &:! %JJJ B ! 8J: $ $ C8J:C :