 we are going to discuss the topics, dynamic model and functional model. At the end of the session, student will be able to analyze a general world problem and create a dynamic model and also create a functional model. A dynamic model consists of objects which model and captures the static structure of a particular system through the object model which is defined. This object model is going to be used to represent a particular objects. But what about the behavior of this particular object? This dynamic model represents the changes to objects and relations over the time. It is the sequence of operations in response to an external stimuli which is control. The first concept that we see while drawing a dynamic model is the states. This is represented as a filled rectangle. Attribute values and links are held by objects. The set of values are grouped by properties that affect the behavior of objects. The response of objects to the input events are taken into consideration. Response varies depending on the attribute values. The state always has a duration in which it will occur. Events like an airplane, flight, departure which can use the attributes airline or flight number or city are individual stimulus from one object to another. The response depends on the state of the object which is receiving it and it includes a change of state that can occur. It now happens at a particular point in time. Two events may follow each other then they are called as causal or they may occur at the same time and the events are called as concurrent. Every event is a unique occurrence of course and the sequence of events which are put together is called as a scenario. So your trace diagrams describes the sequence of events and the objects which are exchanged. The next concept is a state diagram which is a pattern of events, states and state transitions. All these are placed in the network which is developed of states and events. The next state depends on the concurrent state and the event and a graph can be drawn where the nodes are states and directed arcs are transition labeled by each event name and it specifies the state sequence caused by the event sequence. It can represent one short life cycle or the loop. So we are going to put this state diagrams as the state transition diagrams also because we are going to show them in a particular state. Next is can conditions be put into our dynamic model? Yes a condition like if temperature is below a freezing point what has to be done? So it is a Boolean function of the object values. It is valued for an interval of time and is used as guards on a particular transition to happen. We can also use operations in our dynamic model like what objects does in response to the states and events? What is performed in response to the state occurrence or an event occurrence? And what are the real world operations which are not instantaneous in nature? The next concept is activities. We represent an activity by the syntax do activity 1 where 1 is the name of the particular activity operation that takes time to complete is an activity. It is associated with a state. It includes continuous or sequential operations. They are premature if they cause transition before the activity is complete. Concurrency is another concept wherein the concurrence objects exists in the dynamic model and they work at the same time. Each object has its own state and a state diagram. Concurrency occurs on subsets of the attributes or the links. We have also entry and exit conditions associated with entering and existing states and internal actions which are performed without causing the state change, executing between entry and exit actions. However, they are not self-transition based. Therefore, they are called as internal actions. Automatic transitions can happen when we have completion of transition to other state without any event name. Then sending events which is action of sending event to other object by concurrent object like a broadcast or a race condition might occur in such a case because more than one objects are asking for the same resource. A dynamic model thus is a collection of all these state diagrams which we have created and one state diagram for each class is representation and we have important dynamic behavior and pattern or activities and each machine executes concurrently to develop the particular result. For an example, let us consider the list of states and transitions in a cell telephone device system. Here we see for starting your telephone, you require an entry or a start dial tone or an exit or an end dial tone. Once the start tone is established, there is a starting and the dialing has happened. You give a number n, it goes into the dialing state now. There you dialed the number n, you have an entry of the number, you append that particular number and then finally you check whether the number is valid or not. So, from one state you are entering into the other state. This is only I am talking about the telephone device in your telephony system which will have two objects there, two states there. One is the starting state and one is the dialing state. So, we are talking about the states in which the object telephone device can exist. As an assignment, I request you to draw the dynamic model for a hotel management system. Think of all the things that are happening in the hotel management system, the taking of the order, the kitchen associated tasks, the tasks of the waiter giving a good service, the billing system, all these will produce the state diagrams which will collectively make the dynamic model of a hotel management system. To introduce our functional model, we know that the object model captures static structure of the system. The dynamic model represents the changes to objects and relations over time. Now our functional model describes the computations within a system. What are the things to be done to achieve our particular goal are in the form of functions and represented in a functional model. It specifies what happens actually in the system. The first concept we study here is a process. It is a shaded ellipse like curing might be a particular process. Here in a process we transform data. The lowest level process are true functions of its own and each process has a fixed number of inputs and outputs which are data arrows and each carries a value of a given type labeled to show their role and computations of the output values from the input values are specified very well. The next concept is a data flow represented as a directed arrow like an approval of a loan which is shown here on the right-hand side. It connects the output of one object to the process of the input of another. It represents intermediate data values within a computation. It exists between the producer who is requesting and the consumer which will be given this particular item and the same values can be forked at any time. There are flows in the boundaries which are input or the output. The next concept are actors which are a shaded rectangle. For example, a purchasing officer might be an actor. This active object drives the data flow by producing on consuming values. Actors are attached to the inputs and outputs of the data flow graph. They terminate flow of data as sources and syncs of data. They are called as terminators. The next concept is data stores which are shown as parallel lines or files. Here we have an order file as an example. The passive objects are stored data for later access. It does not generate any operation on its own. In response to request to store and access data, the methods of access are like those used for files. The next concept, control flows, they indicate data dependencies. It is a Boolean value, not an input value to the process itself. Specifying operations are processes which are implemented as operations. And bottom and higher level processes are operations. Operations may be mathematical, trigonometric functions, table of input and output values, equations, pre and post conditions, decision tables, pseudo code and natural language statements which tell you what has to be done with the cross sequence of events which are there on the rows and columns. We specify operations by a signature that defines the interface to the operations, arguments required and the values the operation returns. Thus the transformations are defined and the effect on operand objects. These are external and internal operations. The access operations, read or write attributes or links. Non-trivial operations like query, action or activity. We represent a functional model as a data flow diagram which shows functional relationships of values computed by a system. These are graphs showing the flow of data. It does not show control information. It does not show organization of values into objects. They show leveling, hierarchy and nesting. Thus seeing that every small point in your design process is exhibited by this particular model. And a functional model is a collection of all such data flow diagrams which show the flow of values from the external points through operations and internal data stores to external output. They include constraints. It specifies the meaning of operations in object model and actions in the dynamic model. Important dynamic behavior and patterns of the activities are considered and each machine executes concurrently. As an example, let us list the process, data stores, actors and transitions in the equipment ordering system. And here we see we have different processes. The objects are the purchaser and those in the eclipses are the processes which are in creation of order, approval of an order, vendor is an object which expedites a particular order which has to be purchased. So we are having here all the components of the functional model being expressed in a particular diagram which is finally called as a functional model. As our assignment, let us try to draw a functional model for a supermarket billing system. Think about the items, think about the processes mainly for your functional diagram and think about how you are going to generate these particular outputs in a diagram which you are going to give as a collection of all the data diagrams of the processes and finally develop your functional diagram.