SEKE 2012 Proceedings - Knowledge Systems Institute

Input: A resource oriented workflow
Output: The maximum requirement on any type of
resource r i to allow the workflow execute along all
possible paths.
Step 1: Identify all blocks.
Step 2: If no blocks exist, go to Step 4.
Step 3: Identify an inter-most block.
Step 3.1: Calculate each branch’s resource requirement
Rq(r i ) and net consumption Rc(r i ) using formulas (9)
and (10).
Step 3.2: Replace all branches with a single connected
task T b , calculate its r c b and r p b using formulas (10),
(11), (14) and (15) if it is an ES-block, or using (12),
(13), (14) and (15) if it is an PS-block.
Step 3.3: Go to Step 1.
Step 4: Using formula (12) to calcu late Rq(r i ). Output
Rq(r i ).
For example, when we convert the ROWN shown in
Fig. 4(c) to th e one shown in Fig. 5, t he resource
parameters for the equivalent task TS 22 should be
r + i (TS 22 ) = max{ r + i (TS 222 ), r + i (TS 222 )};
r - i (TS 22 ) = max{ r + i (TS 222 ), r + i (TS 222 )}
- max{(r + i (TS 222 ) - r - i (TS 222 ))
+ (r + i (TS 222 ) - r - i (TS 222 ))}.
V. REFERENCES
[1] W.M.P. van der Aalst, “Verification of workflow nets”, Proceedings
of Application and Theory of Petri Nets, Volume 1248 of L ecture
Notes in Computer Science, pp. 407-426, 1997.
[2] M. P. Fanti and M. Zhou, “Deadlock control methods in automeated
manufacturing systems,” IEEE Transactions on Systems, Man and
Cybernetics, Part A, 34(1), 5-21, 2004.
[3] K. van Hee, N. Sidorova and M. Voorhoeve, “Resource-constrained
workflow ntes,” Fundamenta Informaticae, 71(2-3):243-257, 2005.
[4] G. Juh´as, I. Kazlov, and A. Juh´asov´a. Instance Deadlock: A
Mistery behind Frozen Programs. PETRI NETS 2010, LNCS vol.
6128, pp. 1-17. Springer, 2010.
[5] María Martos-Salgado, Fernando Rosa-Velardo: Dynamic Soundness
in Resource-Constrained Workflow Nets. FMOODS/FORTE 2011:
259-273
[6] J. Wang, W. Tepfenhart and D. Rosca, Emergency Response
Workflow Resource Requirements Modeling and Analysis, IEEE
Transactions on Systems, Man and Cybernetics, Part C, vol. 39, no.
3, 270-283, 2009.
[7] J. Wang, D. Rosca, W. Tepfenhart, and A. Milewski, “Incident
command systems workflow modeling and analysis: A case study,”
Proceedings of the 3rd International ISCRAM Conference (B. Van de
Walle and M. Turoff, eds.), Newark, NJ, May 2006.
[8] J. Wang, D. Rosca, W. Tepfenhart, A. Milewski and M. Stoute,
Dynamic workflow modeling and analysis in incident command
systems, IEEE Transactions on Systems, Man and Cybernetics, Part
A, vol. 38, no. 5, 1041-1055, 2008.
[9] N. Wu and M. Zhou, Resource-Oriented Petri Nets in Deadlock
Avoidance of AGV Systems, Proceedings of the 2001 IEEE
International Conference on Robotics & Automation, Seoul, Korea,
May 21-26, 2001
[10] N. Wu and M. Zhou, System Modeling and Control with Resource-
Oriented Petri Nets, CRC Press, Oct. 2009.
IV. CONCLUDING REMARKS
Resource-oriented workflow nets (ROWN) are
introduced in this paper to analyze resources usage and
requirements for workflows. ROWN are an extension to
workflow nets by associating resource change with each
transition that represents resource consumed, occupied,
produced or released when the event that the transition
stands for happens. Transition firing and state change rules
are presented for ROWN. Two approaches for resource
analysis are proposed. One is through reachability analysis,
the other one is based th e ROWN structure. The
reachability approach applies to any kind of ROWN, while
the structure based ap proach only applies to well-nested
workflows but th e analysis algorithm is very efficient.
ROWN are dif ferent from resource-constrained workflow
nets and resource-oriented Petri nets in that these two nets
can only deal with durable resources but ROWN are good
for both durable and non-durable resource analysis.
More work needs to be done in workflow resource
analysis. One is to f ind conditions for a ROW N to be
deadlock free. Another one is considering the possibility
that a task is abolished in the middle of execution.
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