Cyber-Physical Systems

154 Cyber-Physical Systems: From Theory to Practice

Object1 Object2

Clock(event)

Clock(C)

1. DC

2. EC

3. PO

4. EQ

5. TPP

6. TPPi

7. NTPP

8. NTPPi

FIGURE 6.6 The representation of spatiotemporal diagram in RCC-8 with the clock theory.

• EQ(X, Y)—X and Y are equal

• PO(X, Y)—X and Y partially overlap

• TPP(X, Y)—X is a tangential proper part of Y

• NTPP(X, Y)—X is a nontangential proper part of Y

• The inverses of the last two—TPPi(X, Y) and NTPPi(X, Y)

Clock theory [18] describes temporal relations in the event in physical world by using a clock,

and can analyze, records the event by clock. To use clock theory to specify CPS, the time description

is clearer to