“Las líneas que unen tu mundo”
3.2. Propuesta Audiovisual
3.2.8. Reportaje de “Temascal”
MBF 839 QUANTITATIVE TECHNIQUES FOR BANKING AND FINANCE
3.0 MAIN C ONTENT
Mal, 839 QUANTITATIVE TECHNIQUES FOR BANKING AND FINANCE
Note: In addition to activities, events are identified too.
Events mark the point in time when activity is completed and the next activity can be started. Events are normally represented by circles:
Check the brakes wear Figure I
The event
111
represents the point in time when the car is ready to have its brakes tested.Network ?
A network is a convenient method of showing the logical sequence of activities in a project.
Suppose that in a certain project, there are two activities A and B, and activity B cannot be started until activity A is completed. Using the network symbols, these activities can be represented like this:
Figure 2
The event represents the point in time when activity A is completed, but it also represents the point of time when activity B is can begin. This represents the situation when activity B depends upon activity A; when two or more activities are dependent upon the same.
activity. The situation when neither activity D nor E can start until activity C is complete would be represented like this:
MBE 839 QUANTITATIVE TECHNIQUES FOR BANKING AND FINANCE
Figure 3
The event x represents the point of time when activity C is completed, and also the point of time when activities D and E can start, so the diagram clearly shows that D and E depend on C.
Also, it is likely that an activity depends upon more than one other activity. If activity A cannot start until activities G and F are both complete — represent as follows:
Figure 4
Dependence Tables
From the introduction, the first task of network analysis is to sort out the logical sequence of act ivit ies. This is done by constructing a dependency table. List all the activities, next is the list of activities that they depend upon. E.g. there is one way in which the Financial Manager can affect the volume of credit sales and collection period and consequently investment in accounts receivable. This is through a dependable change in credit policy.
Credit policy is used to refer to the combination of three decision variables (assuming) logically:
Introduction Credit Standard Credit Terms Collection Efforts, financial manager has
Preceding activity (a)
(b)
( c ) o n w h i c h t h e influence. Following the preceding activity will enhance proper decision.
MBE 839 QUANTITATIVE TECIINIQUES FOR BANKING AND FINANCE
Constructing a dependence table (trend) is often the most difficult part of project analysis. Obviously, the construction of dependence tables of any action (activity) like that of establishing a credit arrangement is in essence, a team activity. All the experts engaged on the project have to be consulted.
Network Diagram
A network diagram below is composed of a number of arrows and nodes. The arrows represent the flow of project activities. A network diagram is generally the preferred approach for usual po rtrayal of project activities as follows:
Order
Interview Furniture set-up
Locate
umiture
• i r e d
Traine. Move in Remote
•
Figure 5
The network diagram describes sequential relationship among major activities on a project. For example, activity 2 —> 4 cannot be started;
according to the network until activity 1 —> 2 has been completed (figure 4 above).
A path is a sequence of activities that leads from the starting node to the finishing node. Thus, the sequence 1 2 — 4 —> 5 —> 6 is a path.
There are two other paths in the network namely: 1 —> 2 —> 5 6 and 1
— 3 5 6. The path with the longest time is of particular interest because it governs project completion time. The project life cycle equals the expected time of the longest path; the longest path is the critical path, and its activities are referred to as critical activities. The allowable slippage for any path is called slack, and it reflects the difference between the length of a given path and the length of the critical path.
MBF 839 QUANTITATIVE TECHNIQUES FOR BANKING AND FINANCE
Network Conventions
Developing and interpreting network diagrams requires some familiarity with networking conventions. Discussion centres only on some of the most basic and most common feature of network diagram. As above, figure 1, 2, 3 and 4 provides background for understanding the basic concepts associated with precedence diagrams and permits us to solve typical problems. See some more examples like the following:
Figure 6
When multiple activities enter a node, this implies that all those activities must be completed before any activity that is to begin at that node can start. Hence figure 5 — activities "a" and "b" must both be finished before either activity "c" or activity "d" can start.
When two activities both have the same beginning and ending nodes, a dummy note and activity is used to preserve the separate identify of each activity. In the diagram below, activities "a" and "b" must be completed before activity "c" can commence. See figure t below:
Figure 15.7
Note: The 'if' Event Numbering Rule
If the network above consisted of real rather than imaginary activities, then description of each activity would be written above each arrow. It is convenient to use a coding system to describe a particular activity, and we do this by numbering the events according to the 'if' rule. The rule states that the event at the end of an activity must be assigned a greater number than the event at the beginning of an activity. There is no single way of numbering the events, for the 'if rule' allows considerable latitude. One numbering system that obeys the rule is shown in figure 7 below but of course there are many others.
MBE 839 QUANTITATIVE TECHNIQUES FOR BANKING AND FINANCE
We can now describe activity A by its 'if numbers 1 —2.
Example:
Activity Preceding
B and C A
B and C
Figure 9
D
_______4 C
This network does show a logical sequence of activities, but we cannot accept it, as activities B and C both have the same 'if number. This problem is overcome by introducing a dummy activity — represented by a broken line.
MBE 839 QUANTITATIVE TECHNIQUES FOR BANKING AND FINANCE
The dummy activity does not represent any activity as such — it is inserted to preserve the sequential numbering system of events. Such a dummy is called an identity dumni) . Sometimes it is necessary to insert a dummy to preserve not the sequential numbering system, but the logical sequence of events.