ns2 project in lakshadweep

ns2 project in lakshadweep


    ns2 project in lakshadweep the basic component objects of the lift system is

the buttons on the floors or inside the lifts. Buttons

have a common behaviour; they can be pushed On

by people and turned Off by the system. The projection symbol ns2 project in lakshadweep indicates visibility, i.e.

introduces the list of those features (local schema)

which are accessible via the dot notation. If the list is omitted, as in previous examples, all features are

visible. In the class Lift, the attribute fbuts (floor buttons)

models the panel of floor buttons where the ns2 project in lakshadweep index of

the sequence models the floor numbers. The attribute

md and ds models the move direction status and liftdoor

status. The attribute current models the floor

position where the lift is currently at. The attribute

extGoal represents an external request ns2 project in lakshadweep which is assigned

to the lift as a temporary destination. Inside a lift, a floor button can be selected by people.

This action is modelled by operation SelectFloor.

Note that the notation operation1 operation2 denotes ns2 project in lakshadweep

environment enrichment in that the schema

text of operation1 enriches the environment in which

operation2 is interpreted. This environment enrichment

frame also can used to model multiple concurrent

operation interactions. The lift door can ns2 project in lakshadweep be opened  and closed.

There are two kinds of move operations: one

is driven by the external request (MoveToExtGoal),

the other is driven by the internal request . The lift move direction is dominated

by the external request (if it has been assigned

to the lift) rather than the internal request. This is ns2 project in lakshadweep

ensured by the precondition extGoal = @ of the operation

  1. The system safety property (S), “The lift door must

be closed before any movement (Up or Down),” is

ensured by the predicate ds  Closed in the preconditions

of both the operation MoveToExtGoal and

MoveToIntGoal. Also, as preconditions of both the

operation MoveToExtGoal and MoveToIntGoal requires

that there is an external and/or internal ns2 project in lakshadweep request,

therefore the system property (Pl), “When a

lift has no request, it should remain at its final destination”,

is ensured. The system property (P2), “The

lift has to satisfy an external floor request only if it

goes in the same direction or if the request is the external

destination of the lift”, is also captured in the

definition of the operation MoveToExtGoal. As the definition of some operations ToOpenDoor,

MoveToExtGoal and MoveToIntGoal are relatively

complex, to improve the understandability of the

model, we present a finite state machine diagram Figure

2 to highlight the essential behaviour of the lift. Because the main characteristic states of the lift are

the move direction and the door status. A permutation of ns2 project in lakshadweep the cross state space of MoveDzrectzon and

DoorStatus forms the states of the finite state machine

for the lift. Transactions between states are labelled

with Object-Z operations with instantiated preconditions.

The instantiated preconditions for each ns2 project in lakshadweep operations

are also partitioned and labelled so that they

can be presented in a reusable fashion. We believe this

improves the readability of the finite state machine diagram

for a complex system.