project management

Monday, August 28, 2006

Session 10: Reducing Project Duration
Reducing Project Duration, When you want to reduce a project’s duration? You must think about project objectives and project priority matrix, which factors between time, performance, or cost are constrain, enhance, or accept. Because you can not achieve all of time, cost, and quality, when you reduce time, direct cost will increase, and in another way when you reduce cost, time will go up. So you have to find optimum cost-time, and think about another constrain; quality and limited resource (4M).
How to reduce the project duration?
First; find the critical path by write early start time and late start time.
Second; select an activity that has the lowest crashing cost on critical path for reduce time.
Third; check the critical path every time after you reduce time by recalculates ES and LS, because critical path will change and can have more one of critical path.
Forth; continue to reduce time in lowest crashing cost and until you find the optimum cost-time. and
Fifth; draw a graph of cost-duration between costs and duration, consist of 3 linear;
- indirect cost, vary by time its mean time increase indirect cost will increase,
- direct costs, inverse vary by time, its mean time decrease direct cost will increase, and
- total costs (sum of indirect and direct cost). You will find the optimum of cost–duration from this graph. Project manager must to think about another constrain when you use time-cost tradeoff analysis. Because when reduce project time, critical path increase, decrease flexibility of project, increase risk, and some time decrease quality. Brainstorming all of stakeholder, think about project objective and not just only think about technique, you must think about socio-culture too; customer expectations, teamwork, negotiation, politics, problem solving and leadership .

Friday, August 18, 2006

Chapter 8: Scheduling Resources

We learned how to select the resources of the project network and how to optimize the resource, because of resource constraints. Resources are 4M’s: Man, Materials, Machines, and Money. The resources of project are very important, project manager try to balance or allocate the resource in each activities, if you don’t have a good scheduling resource, may be your project is not success, because some resource are not available when you need, no machine, waste time for wait machines, plenty or lack of labor. So Project manager need to do the scheduling resources, select the major one or two of resources. We have to know what are the project constraint, see project priority matrix.
Project usually face to time- constrain or resource-constrain. We have to look at the whole of schedule, and try to balance resource for reduce the problem. How to allocate or balance resources? Time-constrain projects, we use smoothing resource demand by reduce the peak demand first, and fill the resource in the valleys, arrange the resources smooth, and minimize fluctuations. For resource-constrained, not available and insufficiency of machines, we need the use of rule of the thumb (heuristics); first priority is minimum slack, second is selected smallest duration, and last is select the lowest activity identification number.
The best way to understand the project network and scheduling resource is do it by yourself, learning by doing, use the Microsoft project, follow the basic roles first, do it and do it, try to find the better and better way to allocate the resource, minimize the resource and maximize the resource utilization.

Friday, August 11, 2006

Chapter 6: Developing a project plan (continue)
The project network

Last week I learned about AOA and bar chart of the project network. In this week, we start with a question: if you want to decrease a project time, what will you do? The first, I tried to reduce the critical path time, but some activities are fixed, we can’t do. We can do by divide of some activities by logistic thinking (activities on node need logic), use of lags time: start to start relation (SS), or finish to start relation (FS). Form example: the pipeline project, it has 5 activities, mobilize and survey (MS), excavate trench (ET), purchase pipe (PP), lay pipe (LP), and backfill (BF). We can divide ET to 3 sub activities, after finish the first sub activities, we can start LP, use of lags time or start to start, SS = 2, it means after ET start 2 days, LP will start, we no need to wait until SS finish (finish to start). SS can reduce the project time 3 days.
We can reduce the project time by use of lags:
FF: Finish to Finish
SF: Start to Finish
SS: Start to Start
Hammock Activities mean the activity span over a segment of a project, use to aggregate section of the project to smooth the right amount of detail for specific sections
Basic rules of project network
Networks flow from left to right.
An activity cannot begin until all of its activities are complete. (ES)
Arrow indicates precedence, flow, can cross over.
Activity number: a unique number, and greater than its predecessors.
No looping.
No condition
Use common start and stop nodes.

The first I tried to do an AON by Microsoft Project, after finish, I read basic rules of project network, and found some mistake, such as: number of activities that smaller than its predecessors (I adjust a sequence again, make a sequence follow a number in right hand must bigger than left hand), some path not connect to their predecessors, and some activities are same name but different group (use indent). I think we have to understand and follow the basic rules in developing project network; the rules can help project manager and participants easy to understand the network.

Friday, August 04, 2006

Chapter 6: Developing a project plan
The project network

Engineering project management teaches me step by step about how to plan and develop a project. Start from what is a project, what do you want to do (try to reach customer need or satisfy and optimize resource), who response, when do you do, how long, and how much. You should have to answer these questions, and do a plan: mission, goal, selected a project, selected strategies, selected implement, and forecast time and cost, after finish a plan, you will develop the project by draw the project network.
Chapter 6, we learned developing a project plan, related to the project network. The project network come from work package (WBS), show detail: activities, sequence and relation of each activities (this one finish, another one will start), activity time (from start to finish: Early Start or Late Start), tell the shortest time that a project can completed: Critical path (you can not delay in critical path, it will make a project delay), and float path (you can delay in float path, but not more than total float time). The project network usually shows in Bar chart/Gantt chart, or network diagrams; 2 kinds, Activity on Arrow (AOA) and Activity on Node (AON), easy way to understand all of project process, easy to follow a plan, show the critical path, forecast a project time, activity time, show cash flow, decrease the problem, and help project manager make decision in the right way.
Example: page 183 q. 9