Project Report of Electricity Billing System Page 1

Project Report of Electricity Billing System 
 
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objects. In UML, this grouping mechanism is package. The term package diagram for a 
diagram that shows packages of classes and the dependencies among them. 
A dependency exists between two elements if changes to the definition of one 
element may cause to other. With classes, dependencies exist for various reasons: one 
class sends a message to another; one class has another as part of its data; one class 
mentions another as a parameter to an operation. A dependency between two 
packages exists; and any dependencies exist between any two classes in the package. 
State diagram
: State diagram are a familiar technique to describe the behavior of a 
system. They describe all the possible states a particular object can get into and how 
the objects state changes as a result of events that reach the objects. In most OO 
technique, state diagrams are drawn for a single class to show the lifetime behavior of a 
singe object. There are many form of state diagram, each with slightly different 
semantics. The most popular one used in OO technique is based on David Harel’s state 
chart. 

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Project Report of Electricity Billing System 
 
Page - 27 
PERT CHART (Program Evaluation Review Technique) 
PERT chart is organized for events, activities or tasks. It is a scheduling device that 
shows graphically the order of the tasks to be performed. It enables the calculation of 
the critical path. The time and cost associated along a path is calculated and the path 
requires the greatest amount of elapsed time in critical path. 
 
PERT Chart representation 
Specification 
Design 
Database 
Part 
Design GUI