Project
2001
PROJECT
CONTROL SYSTEMS
The purpose of controlling
a project is to monitor the
progress the activities against
the plans, to ensure that the
goals are being approached and,
eventually, achieved. Another
aspect of control is to detect,
as soon as possible, when deviations
from the plan occurring so that
corrective action may be taken.
In software engineering, as
in any design-dominated discipline,
it is especially important to
plan realistically even conservatively-so
as to minimize the need for
corrective action. For example,
while in a manufacturing -dominated
discipline it may be justifiable
to hire the minimum number of
workers necessary and add more
employees if production falls
below the required level, it
has been observed in software
engineering that adding people
to a project that is late can
delay the project even further.
This underscores the importance
of not only planning, but also
controlling, in software engineering.
The deviations from the plan
are detected, the more it is
possible to cope with them.
Work Break Down Structures
Most project control techniques
are based on breaking down the
goal of the project into several
intermediate goals. Each intermediate
goal can in turn be broken down
further. The process can be
repeated until each goal is
small enough to be well understood.
We can then plan for each goal
individually-its resources requirements,
assignments of responsibility,
scheduling, etc.
A semiformal way of breaking
down the goal is called the
work breakdown structure (WBS).
In this technique, one builds
a tree whose root is labeled
by the major activity of the
project such as build a compiler.
Each node of the tree can be
broken down into smaller components
that are designated the children
of the node. This work breakdown
can be repeated until each led
node in the tree is small enough
to allow the manager to estimate
its size, difficulty, and resource
requirements. Figure 1 shows
the work breakdown structure
for a simple compiler development
project.
The goal of a work breakdown
structure is to identify all
the activities that a project
must undertake. The tasks can
be broken down into as fine
as level of details as is desired
or necessary. For example, we
might have shown the substructure
of a node labeled design as
consisting of the three different
activities of designing the
scanner, parser and code generator.
The structure can be used, as
a basis for estimating the amount
of resources necessary for the
project as a whole by estimating
the resources required for each
leaf mode.
The work breakdown structure
is a simple tool that gives
the manager a framework for
breaking down large tasks into
more manageable pieces. Once
these manageable pieces have
been identified, they can be
used as units of work assignment.
The structure can be refined
and extended easily by labeling
the nodes with appropriate information,
such as the planned length of
the activity, the name of the
person responsible for the activity,
and the starting and ending
date of the activity. In this
way, the structure can summarize
the project plans.
The work breakdown structure
can also be an input into the
scheduling process, as we will
see in the following figure.
In breaking down the work, we
are trying to decide which task
need to be done. In scheduling,
we decide the order in which
to do these tasks…Each
work item in the work breakdown
structure is associated with
an activity to perform that
item. A schedule tries to order
the activities to ensure their
timely completion.
Timeline Charts (Example
of Detailed Schedule) :
When creating software project
schedule, the planner begins
with a set of tasks. If automated
tools are used, the work breakdown
is input as a task network or
task outline. Effort, duration,
and start date are then input
for each task. In addition,
task may be assigned to specific
individuals.
As a consequence of this input,
a timeline chart, also called
a Gantt Chart, is generated.
A timeline chart can be developed
for the entire project. Alternatively,
separate charts can be developed
for each project function or
for each individual working
on the project.
In the figure illustrate the
format of a timeline chart.
It depicts a part of a software
project schedule that emphasizes
the concept scoping task. For
a new word-processing (WP) software
product. All project tasks are
listed in left hand column.
The horizontal bars indicate
the duration of each task. When
multiple bars occur at the time
on the calendar, task concurrency
is implied. The diamonds indicate
milestones.
Once the information necessary
for the generation of a timeline
chart has been input, the majority
of software project scheduling
tools produce project tables-
a tabular listing of all project
tasks, their planned and actual
start and end dates, and a variety
of related information. Used
in conjunction with the timeline
chart, project tables enable
the project manager to track
progress.
Work tasks Week1 Week2 Week3
Week4 Week5
1.
Identify needs and benefits
Meet with customers
Identify needs and project constraints
Establish product statement
Milestone : Product statement
defined
2.
Defined desired output/Control/input
Scope keyboard functions
Scope voice input functions
Scope modes of interaction
Scope document diagnosis
Scope other WP functions
Document OCI
FTR:Review OCI with customer
Revise OCI as required
Milestone : OCI defined
3.
Define the function / behavior
Define keyboard functions
Define voice input functions
Describe spell / grammar check
Descrobe other WP function
FTR: Review OCI definition with
customer
Revise as required
Milestone : OCI definition complete
4.
Isolation software elements
Milestone: software elements
defined
5.
Research availability of existing
soft.
Research text editing components
Research voice input components
Research file management component
Research spell / grammar check
comp
Milestone: Reusable components
iden
6.
Define technical feasibility
Evaluate voice input
Evaluate grammar checking
Milestone: Technical feasibility
assess
7. Make quick estimate of size
8. Create a scope definition
Review scope document with customer
Revise document as required
MilestoneL Scope document complete.
