Industrial Project Management: A Handbook of Planning, Scheduling & Evaluation Techniques
i). Schematic models
In schematic models a logical correspondence between activities, tasks, executives,
time schedules and resources is created, which is later easily transferred into a graphi-
cal relation. The graphical relation allows the manager to follow directly and observe
the logical links in time, to control the performance of individual tasks with respect to
time schedules and consumption of resources . And to look for additional provi-
sions in both re-distribution of tasks between executives and it reducing the time
needed for the performance of individual activities as a result of which the overall time
is thus reduced .
The Gantt chart method is a typical representative of graphical models. Gantt charts
represent charts spread out in time giving the relevant indications of tasks to be exe-
cuted. These chronograms, along with activity planning make it possible to give
graphical indications of activity work progress. Thus, process management is largely
visualized and allows the manager not only to control performance but also find out
when (in what time intervals) he can expect piling up of several parallel activities and
hence, some organisational and technical difficulties that might occur . This en-
hances the search for possibilities for re-distribution of tasks or avoiding difficulties by
advancing or moving some activities back in time. It can be noted here that Gantt
charts are a good graphical technique allowing the manager to both plan and control
task execution .
Network models (CPM, for example) are some of the most widely used graphical
models. Network analysis is a technique for planning and control of complex projects
and developing time schedules for resources needed for products to be manufactured.
It achieves this aim by analyzing the component parts of a given product and evaluat-
ing the consecutive interrelations between each event . The results of this analysis
are presented as a network diagram of internally linked activities.
The idea in the contents of the network planning is close to that of programmed-goal
planning (or the linear programming methods) but the technique for the realization of
the process of implementation of the method is different. Here, again the basic thing is
to break down the process of implementation of the decision into separate elementary
tasks or operations that have to be performed in time and pointing out their interrela-
tion and logical link in time and space in a connected graph (network) in which the
separate elements could represent events or obtained partial results and the links be-
tween them (the columns in the graph) represent operations, activities.
The advantage of this process is that the final result features good visual presentation
and systematical analysis of the process of implementation of decisions and the se-
quence for accomplishing individual tasks. Also, numerical characteristics for the
overall duration, the total resources required and last but not least – for those routes in
the network that are critical for the accomplishment of the overall program are ob-
tained. Critical here means that every extension of activities or every increase in re-
sources consumption along the critical path would lead to overall increase in the dura-
tion of the performance or overall increase in the cost of the entire program .
Another advantage is that some very well developed application software packages are
available for using computer equipment for building and calculating network graphs.
With the help of this software one can plan the accomplishment of individual opera-