32 (168)

Analyzing Workflows 135

	D1	D2	D3	D4	D5	D6	D7	D8	D9
Taskl	C	C
Task2		R				C
Task3						R	C
Task4	R		C
Task5	R	R		C
Task6		R	R	R	C
Task7	R	U			R		R
Task8							R	C
Task9	R	R						R	C
	(C=Create, R=Read, U				=Update, D^;		=Dele1	e)

Figurę 4.37 CRUD matrix

(i)

begin    receive_mail

Figurę 4.38 E-mail

(c)    Improve the process by making it morę parallel.

(d)    Is it a good idea to combine tasks? If so, which tasks are proper candidates?

Exercise 4.2 Invariants

Consider the Petri nets shown in figurę 4.38, figurę 4.39, figurę 4.40, and figurę 4.41.

Answer for each Petri net the foliowing questions (see appendix A):

(a)    What are the place invariants (maximum 5)? What do they show?

(b)    What are the transition invariants (maximum 5)? What do they show?