 Hello friends, we are going to discuss today about scheduling. We have discussed what is routing and what are the various aspects of routing in the last session. And as all of us know that PPC involves the stages like routing, scheduling, dispatching and follow-up. Out of that, the second important step of PPC scheduling, we are going to discuss what scheduling means today. And the session will be able to understand the meaning of scheduling, its objectives and principles of scheduling and also you will be able to differentiate between scheduling and routing. The contents will be like this, definition, objectives, principle, types, factors and what are the strategies, what is the difference between the routing and scheduling. What does it mean by scheduling? We have got so many definitions of scheduling and what exactly scheduling means to all of us. What does it mean by scheduling? What is scheduling? It is a very simple definition. In simple terms, scheduling is preparation of detailed timetable. All of us know that railway or aeroplanes, flights, they have got their schedule fixed. If you know, you are travelling from one station to another station and if you just go to the site, if you just go to the site of suppose IRCTC, IRCTC will give the detailed train from which station it departs, at what time it departs, where it will halt and how much time it will halt and when it will reach to the required destination. All this is called as scheduling. This is the scheduling of that train from one station to another. The same thing is true, the same meaning is applicable in the production system, in the operation system as per scheduling is concerned. It is the determination of time that is required to perform each operation and also the time required to perform the entire series as routed is called as scheduling. It also involves preparing complete and detailed timetable of all the processes. We have decided the route, how the route is to be there, we have decided the route in the routing and then we are giving you exact timetable of each of the process start of the process and end of the process, how much time it will take, where it will be done, all these things will be involved in the scheduling. It is a detailed timetable preparation. Why to do scheduling? What is the objective? What are the various objectives? It is the to achieve the required rate of output with minimum delay, to meet delivery commitments of the customers, to have maximum utilization of the available resources, especially into main material machines and all the equipments. And as a result of all these three above, finally it should result into the minimization of the production cost, thereby getting the required profit of the organization. There are some principles of scheduling when you talk about some principles. It is the principle of optimum task size. It tends to achieve the maximum efficiency when the task sizes are small and all tasks are of the same order of the magnitude. The principle of optimum production plan, it is such that it imposes an equal load on all plants and the principle of optimum sequence is that it tends to achieve the maximum efficiency when the work is planned, so that work hours are normally used in the same sequence. There are three different approaches, three different principles by which we can schedule. Each one will having a typical focus. Of course, organization depending upon their priority will use one of these principles for scheduling. There are mainly types of schedules. There are two types of schedules, one is called as forward scheduling and the other is called as the backward scheduling. Forward scheduling is most commonly it is from start to end, where it is commonly used to job shops where customer places their orders on needed as soon as possible basis. For example, customer has given an order and the customer says that generally if you just look at it, it is a common feature amongst all the customers that they want it on a very, very urgent basis. Even they place the order and then generally take with a common joke that I wanted it yesterday. So they are placing the order today that indicates that how much urgency that particular delivery is. In that case, we have to go for forward scheduling where customer is asking for as soon as possible basis customer is not committing a particular date. Then we have to see that when we can start it and then optimize each of the route and then finally decide the time required so that if I start today, what is the minimum time required and then I can commit that okay, after 10 days it is possible, after 15 days it is possible. So starting from start today to end of this, whatever I scheduled it is called as forward scheduling. And therefore this method generates in process inventory that are needed at the subsequent work centers and it results into higher inventory cost. Of course it is obvious that the inventory will be there and it increases the WIP at all the various processes. And one of the major feature is that it is very simple to use and it gets job done in shorter lead time as compared to backward scheduling. So very simple, we have to start today and then go on adding the various sequences and various schedules. And therefore you will have the final end date that is called as forward scheduling. Very simple but as needed by the customer we have to go for this particular schedule. The other method is backward scheduling where it is often used in the assembly type of industries and commit in advance to specify delivery dates. I have to go for the specific delivery dates. Suppose customer wants it on the particular date then I have to take as the planned delivery date and work in all the other activities in the backward mode. That is the end date which is fixed one. And they may be because of some reason the customer has said that I have to commence this particular plan to buy this date. So therefore you have to deliver me on this date or before that date. Then I have to take that date as the ultimate delivery date and then do the scheduling in an absolutely reverse manner starting from start end date where coming to the starter date that is called as backward scheduling. In forward date, in forward scheduling we start with the start and then end with the sequences whatever possible is there. The starting point is in case of the forward scheduling is the receiving of the order and then going forward up to the end. In case of backward scheduling we start with the end date which is prescribed by the customer and then we schedule all other things in the backward mode this is called as backward scheduling. It minimizes the inventory since the job is not completed until it must go directly to the next work center on its routing. So of course in WIP and inventory processes in backward scheduling is less as compared to forward. Below of material and lead time estimates are maintained for all work centers otherwise the system breaks down and due dates are violated. So we have to take off lead time estimates very correctly. What are the various factors affecting scheduling? Stock as usual you know. Time interval to process finished goods from raw material that is the entire cycle time which is required, availability of the equipment and machines, availability of the manpower and availability of the material. These are the various factors which I have to consider before I schedule the activities. Unless I take all this into consideration like availability of manpower or availability of the equipment their utilization all these things have to be thought of otherwise I plan it I schedule it and then suddenly the non availability of the manpower will create a problem in the entire delivery dates and there are some external factors which are beyond the control of the organization like customer demand, uneven demand and unpredictable demand that is a general factor for demands. Customer delivery dates customer ask sometimes before your lead time or before your cycle time that is another big challenge while you schedule in case of various orders and stock of goods already lying with dealers and retailers that is one more factor which are beyond the control the various work centers and the various depots those are there where the stocks are there and the stocks already have some effect on your scheduling. We cannot we can't predict when that particular sale of the particular inventory is going to happen and therefore it creates some problem for the scheduling. The strategies are detailed scheduling and community scheduling there are two methods of scheduling detailed scheduling is for a specific job and impractical in manufacturing situations and community scheduling is as the work goes on may load to the current period excessively and therefore it is under load future period okay. Now and the finally what is the difference between routing and scheduling as of us know routing deciding the route and all of us know what they scheduling it is a detailed timetable and the question now here is what is the difference between the routing and scheduling well these are the points routing is selection and fixing up the path whereas scheduling is establishment of moment of work done and time of each operation. Routing involves the functions and operation and sequences whereas scheduling involves time element for the priorities the main aim of the routing is determined the best and the cheapest sequence of operations whereas main aim of the scheduling is determined realistic delivery dates. Routing answers the questions where the activity should be carried out whereas scheduling answers the questions where it shall be done right. So these are some of the thank you very much.