Multi Project Scheduling, Essay Example

Though the traditional projects scheduling techniques like the critical path method (CPM and the Projects Evaluation and Review Techniques (PERT) have been used by major corporations and non governmental agencies for a very long time in scheduling their projects. However, the major drawback of the traditional projects scheduling techniques is that they assume that the amount of resources available for the projects are infinite and will always be available for the projects team at all times. Nevertheless, problems arise in complex project scheduling situations characterized by both resource constraints and precedence constraints. Major projects scheduling problems with such tendencies can be termed as resource constrained project scheduling problems (RCPSP)

Though there are many ways of completing the resource constrained  project scheduling problems  like minimization of projects schedule and or minimization of the total projects costs, the projects manager may try leveling the resource usage or maximizing the  present net value of all the major cash flows expected from the projects.

It is imperative to note that when faced with a multi project scheduling problems with resource constraints; it is recommended that the projects manager uses one of the following techniques to overcome such problems. The techniques include Zero-one linear programming formulation of projects, (Science Direct, 2008):

1. The shop scheduling problems,
2. The game theory,
3. The decentralized multi projects scheduling method ore
4. The decomposition approach to multiple projects scheduling

A Zero-One (Zero to One)

The (0-1) linear programming formulation of multiple projects is the method of multi projects scheduling techniques that are computationally tractable than the other formulas above. The major advantage realized from this method is that it can be used to accommodate a wide range of practical problems like the multiple resource constraints, job splitting as well as resource suitability and even the concurrency of projects performance requirements. The major objective so the zero-one technique is the:

1. Minimization of the projects throughput time
2. Minimization of the projects duration
3. Minimization of the projects totals lateness (Rinnooy, 1983).

On the other hand the projects manager faced with resource constrained projects scheduling problem may use the decomposition algorithm in solving any resource limited (time, money, personnel or material) multi projects scheduling problems. The distinct advantage of the decomposition algorithm over other direct optimization approaches is that The decomposition approach has the ability to solve large problems realistically. The decomposition method can be used heuristically to provide a measure of performance on the possible feasible solutions to projects problems. In this way the user can determine whether it is worth going on with projects in the light currents problems.

In this method a generic Meta heuristic A generic meta-heuristic structure for the problem under consideration is usually adopted by initially decomposing the whole problem into multiple schedule generations problems and then sequencing the small problems. The sequenced problems are then solved by introducing an effective forward and reverse schedule generation (FRSG) methodology and complete local searches with memory respectively. (Rismondo, 2002)

Recommendation

Amongst the two methods it is advisable to choose the methodology that you as the project manager consider applicable in that particular situation without ignoring the constraints you are faced with.

References

Blazewicz, J. J.K. Lenstra, A.H.G. & Rinnooy, K,. (1983). Scheduling subject to resource constraints: Classification and complexity. Discrete Appl. Maths; 5:11-24.

Reg PE-II FM (Doubt) – Exams Forum – Chartered Accountants … (n.d.). Retrieved from  http://www.caclubindia.com/forum/reg-pe-ii-fm-doubt–34184.asp

ScienceDirect – European Journal of Operational Research … (n.d.). Retrieved from http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235963%232003%23998509997%23430180%23FLA%23&_cdi=5963&_pubType=J&_auth=y&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=4ca59a74ba55c086cb0e06e1f63c4b91

Confessore, G., Giordani, S., Rismondo, S., 2002. An auction based approach in decentralized   project scheduling. In Proc. of PMS 2002 – International Workshop on Project Management and Scheduling. Valencia, pp. 110-113.

Blazewicz, J., Lenstra, J.K., Rinnooy Kan, A.H.G., 1983. Scheduling subject to resource constraints: classification and complexity. Discrete Applied Mathematics 5, 11-24.