Sunday 25 December 2016
Wednesday 19 December 2012
Thursday 29 March 2012
DEVELOPING A GANTT CHART OR A BAR CHART - PMP Exam Tutorial
DEVELOPING A GANTT CHART OR A BAR CHART
PRACTICE PROBLEM:
Identify key short-commings of the presented Bar Chart
COARSE UNITS
Most project plans can be estimated with days as the unit of
time, but in this case the unit is too coarse and half-days would have
been better. For example, it will not take a whole day to make and
position the formwork for the concrete base. Half-days are often
convenient units for small projects, especially where there are five
working days in a week, because a week is then ten units.
Another fault with the bar chart in Figure 2.2 is that it does not
show weekend days. Although most jobs will not have any activity
during Saturdays and Sundays, on this project paint will continue to
dry over a weekend and concrete will continue to cure. So the chart
should include Saturdays and Sundays for those reasons. When the
chart is drawn by hand, the contractor can use his or her mental
powers to determine which activities will run through weekends.
When, as in later chapters of this book, a computer is used, special
steps must be taken to instruct the computer as to which activities
run five days per week and which can take six or seven days.
There is a fundamental flaw of logic in this first bar chart
attempt. All jobs are shown in a simple sequential series. Broadly,
the jobs do follow the sequence that construction would need on site
but some of these jobs could take place simultaneously (provided
enough workers are on hand). To take just one example, the
concrete for the car hard standing area could be poured at the same
time as the workshop base – provided we have not forgotten to dig
the soakaway first.
So, bar charts are excellent for displaying working schedules but
they are by no means the best way of working out and showing the
logic of how the start of one job is dependent on the finish of
another. For very small projects this can be overcome to some
extent by the use of linked bar charts.
The Need for Project Planning
Inow that you decide to team up with a business partner, so that you can expand your business in a modest way. Your projects might now be a little bigger – perhaps three or four houses on one site and another three or four projects waiting or even started. You have a small number of regular helpers or employees. You know where to go for materials, and if you look like running short you have your mobile phone and can call for fresh deliveries. You have to give your specialists, such as the chippy, plumber, roofer, glazier and electrician, some idea of dates when they will be needed and you must keep in touch with the local buildings inspector. Your
different projects have different clients and different architects and
you are expected now to go to the occasional progress meeting. So
you will have to do some planning to schedule and coordinate all the
work. You may not need to learn any new techniques, but you will
have to find some way of putting your plans on paper, because the
work is becoming too complicated to deal with in your head alone.
Plans for small projects can be simple charts. You don’t have to
use a computer if you don’t want to, although that would give you
advantages of speed and flexibility to change. A sharp pencil, eraser,
squared paper, a ruler and a calendar are all you need. But as your
business expands and your projects also grow in size, the time will
come when you’ll need to take planning methods more seriously.
different projects have different clients and different architects and
you are expected now to go to the occasional progress meeting. So
you will have to do some planning to schedule and coordinate all the
work. You may not need to learn any new techniques, but you will
have to find some way of putting your plans on paper, because the
work is becoming too complicated to deal with in your head alone.
Plans for small projects can be simple charts. You don’t have to
use a computer if you don’t want to, although that would give you
advantages of speed and flexibility to change. A sharp pencil, eraser,
squared paper, a ruler and a calendar are all you need. But as your
business expands and your projects also grow in size, the time will
come when you’ll need to take planning methods more seriously.
Wednesday 28 March 2012
PMP CPM Analysis - Problems Including Lag Times in a SS Relationship
CPM ANALYSIS INVOLVING LAGS
Finish to Start and Start to Start Lags Worksheet
Answer Sheet
This tutorial explains how to do a forward and backward pass where there is a lag involved in a start to start relationship.
PMP - Doing a forward and backward pass for CPM Analysis
CRITICAL PATH METHOD
An Idiots Guide on how to plan a project
Step 1: Watch the YouTube Video on the process of doing a forward and a backward pass.Step 2: Do some practice
Practice sheet is available from clicking this hyperlink
Answer sheet can be accessed by clicking this hyperlink
Tuesday 13 December 2011
Precedence Diagramming Method (PDM) or Activity on Node (AON)
The precedence diagramming method or Activity on Node Method
Video Explanation of Key Concepts
Practice Sheet to Support Above Example Demonstrated in the Video
Answer Sheet to Support Above Example Demonstrated in the Video
The precedence diagramming method or Activity on Node Method
The precedence diagramming method (PDM) is what most project management software programs use today. Precedence diagrams connect activities with arrows that show dependencies between the activities. This method is also called activity on node (AON).
The activity information is written on the nodes with arrows connecting the nodes, or dependent activities. The nodes are shown as rectangles, and you are free to put as much information about the activity on the node as you’d like. The minimum information that should be displayed on the node is the activity name. Sometimes the nodes are displayed with activity name, activity number, start and stop dates, due dates, slack time, and so on.
The activity information is written on the nodes with arrows connecting the nodes, or dependent activities. The nodes are shown as rectangles, and you are free to put as much information about the activity on the node as you’d like. The minimum information that should be displayed on the node is the activity name. Sometimes the nodes are displayed with activity name, activity number, start and stop dates, due dates, slack time, and so on.
Keep in mind that the construction of these network diagrams might bring activities to light that you missed when defining your activity list, or it might make you break an activity down into two activities in places where you thought one activity might work. If this is the case, you will produce activity list updates based on this new information.
FOUR TYPES OF PRECEDENCE RELATIONSHIP
Finish to start (FS)
This is the most frequently used logical relationship. This relationship says that the independent, or from activity, must finish before the dependent, or to activity, can start.
Start to finish (SF)
The start to finish relationship says that the independent activity must start before the dependent activity can finish. This logical relationship is seldom used.
Finish to finish (FF)
This relationship says that the independent activity must finish before the dependent activity finishes.
Start to start (SS):
This relationship says that the independent activity must start before the dependent
activity can start. Keep these logical relationships
Graphical Evaluation and Review Technique (GERT) and System Dynamics models,
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