So, first of all, welcome to IIT Bombay and truly HALTI welcome because most of you have come at the shortest possible notice. Let me assure you that we organize our workshops with at least two months of preparation behind all of your board. Without further ado, I would like to start off with a brief introduction of my team here. I am Deepak Phatak. I teach here and I am the principal investigator of this project for launching nationwide Scala program online courses. Professor Lagu, he was my colleague for many years. Then he was an entrepreneur. Then he worked in high-tech areas with TCS and Intel and few months ago he retired from everything, wanting to do something specific in higher education online. So, I caught him and he has joined us as an advisor. He will later on be speaking to you on the third day, telling you about the Section 8 company which is the not-for-profit company which is proposed to be set up to take this thing forward. Professor Pradeep Verma is the senior consultant in MHRD in the national mission and the reason he is moving out and in and he will continue to do so is because the MHRD's main website is being launched at 11 o'clock as we speak. So, instead of being in Delhi, he is in Mumbai and therefore lots of problems. We have our team, Kalpana Kandan is our content chief and she has been currently the program manager for our EDX initiatives. Sitting next to her is Jaya. She handles the finances. So, anybody has any problem with any TA bill or something, you know whom to contact. There is another important person here. I do not know why he is sitting in a corner. He will be speaking to you tomorrow. Professor Uday Gayatunde along with me, he is teaching a course on the international EDX platform on thermodynamics and he will be sharing with you his experiences of running the course on an online platform tomorrow. Sajjan Dixit is in charge of the entire video team. I will mention the backdrop of how we have created these teams but currently he looks after all the video recording and editing and uploading of files for the MOOCs courses. In fact, all the video recording that is happening here with his team, we have a fairly large workshop team which actually handles workshops for training teachers under our T10KT program about which I will briefly mention. And the team members here including those whom we met outside for the registration all belong to that workshop team. In fact, all logistics arrangements are handled by them for the workshop. Anybody I have missed from my team, you will be meeting many of them. There are more than about 100 people who have been working for last three years here and we are using that resource immediately to launch the nationwide camp. I would request all of you to introduce yourselves briefly and then we can start the business. So, I am Atul Negi from University of Hyderabad and I have been asked by my Vice Chancellor to be the coordinator for the activities at University of Hyderabad. Soon I am getting to know that what it will really mean and involve. My name is Upendra and I am from the English and Foreign Languages University Hyderabad and I came to know last week that I am in charge of this program. I am Dr. J. Kishan. I am from Institute of Lifelong Learning, Delhi University and I am the lead faculty for this project. I am R. K. Vyas. I am also from Institute of Lifelong Learning, Delhi University. I am ICT, coordinating the ICT activities in IEEE and lead faculty in computer science for this. Myself Pradeep Kumar, working as a system programmer at NITPALTR Chandigarh. I am Prof. Ramakrishna from Department of Computer Science and Engineering, National Institute of Technicalities, Training and Research Chandigarh. I am the course manager. I came to know two days before. Thank you, sir. I am Mohammad Kasim from Mass Communication Research Centre Jamia Malia University. So, I also came to know that I am the coordinator for the university last week only. Thank you. I am Dr. Shatrud. I am research scientist in consortium for educational communication in New Delhi. I am Nageshwana from consortium for educational communication in New Delhi. We are in the business of right now the e-content creation for UG courses. Good morning, sir. I am Dr. Jyotsana Dixit. Currently, I am coordinating the technology enabled activities at IGNO. Yesterday, I came to know that I have to attend this workshop and since our vice chancellor, we were not able to contact him from the past three days. So, regarding the course and the lead faculty, it is yet to be decided. Yeah, myself, Prof. Shriya Kumar, yesterday morning, I came to know around 10 o'clock that I am supposed to be here. So, I am here and I am from Banaras Hindu University, professor of physics basically. So, I am really totally unaware what is exactly going on. But, I am aware about the MOOC program. So, that… I am Dr. Shri Narayan Hoja from Vishwabhati. I also learned about my status as coordinating this MOOC activities in my university almost 14 to 15 hours earlier than my departure. So, that is how things are happening. I am Orinda Matacharya from IIM Calcutta. I am the coordinator for this course. Good morning, I am Manju Jayaswal. I am from IIM Calcutta. Good morning, I am Preetam Basu. I am also from IIM Calcutta. I am from the operations management department. Actually, Saibal wrote to me very recently and I am very pleasantly surprised to see all three of you here from IIM. Thank you so much. I am Sameer and I come from Tata Institute of Social Sciences. Along with me, there are couple of faculty members. I am Madhu Sri Shekhar. I come from Tata Institute of Social Sciences, Mumbai. Which subject do you handle, Madhu Sri? I have come from a non-technical background. I have come from a political science background but I have been asked by our chancellor to come here. So, I don't come from a technical background. No, no, no. You will be teaching a political science course in MOOC or MOOC? No, I teach multiple papers, many courses at this. So, one of those subjects… Could be on… I teach governance… You have not yet decided. Yes, I could teach it. You are in guru company. Yes. Same confusion prevails amongst most of us here. So, don't worry. I am Shohini Sengupta from School of Social Work, Tata Institute of Social Sciences. I teach social policy. It's one of the subjects. Social? Social policy. Oh, social policy. While the mic is being shifted, let me introduce a few more colleagues who are joined in. Dr. Mukta Atres with us now. Mukta, can you just stand up? I can show her, yes. So, she is the coordinator for the entire workshop team. And I have two very key people. They will be helping you during the lab sessions, Vrinda and Urmila. They are the ones who have helped both Professor Gayathonde and I in creating all our courses in better understanding how to create courses and how to launch them. So, as of today amongst all my technical team, these two happen to be the most key resources. And I pray to God for their good health every night. My name is Anirbhan Hazra. I am from Aisarpune, Faculty of Chemistry. And I should introduce particularly to you, you are my teacher in 1994 of CS 101. Oh my God. Yeah. Got that. Okay. So, that is why the face is familiar. Yes. 94. I am Bhas Bapat. I ought to come from Aisarpune and I will be coordinating the Aisarpune efforts. Bhas, I got the letter from your receiver. Saurabh Bhutolia, technical officer. Hi, sir. But I thought you were not to come today. Okay. You are to come for one day today. The other person is coming for the third day. Right. And you are there for all this. I will be there all through. And the main physics faculty member who is going to first offer the course, he is in Italy. He is in Italy. Yeah. But he will be coming back on the 20th. So, he will come directly from Bombay Airport to the… No. He will be done by then. He is coming only in the 20th. Okay. So, thank you very much. You would have figured out one thing from these introductions. Practically, none of the people participating in this thing were aware of what is going on till about 10 days ago. In fact, most people had no clue. This is just one sign of how fast the government of the day wishes to function. And I think it is important that we match that speed, which means a couple of things. Decisions will have to be taken very quickly. And decisions will have to be taken what I roughly call the armed forces style. If the general is not available, a Brigadier takes a decision. If the Brigadier is not available, a Colonel takes a decision. Write down the link on the battlefield. If nobody is available, a Javan takes a decision. And that becomes the decision of the entire armed forces. That is exactly how we will have to function. So, let me first tell you about the genesis of how the entire MOOC thing came about. It starts with the distance education efforts.  Open universities across the world have been doing it for ages. Ignore representative is here. In fact, what we call the flip classroom where the course material is in the hands of students. They study it. Then they come to a contact center for interaction with faculty for clearing their doubts, etc. It was the earliest form of what today we call a flip classroom in which there are no lectures. Students listen to their lectures in their hostels, but come to the classroom to solve problems and have discussions. In IIT, Bombay, we have been running such flip classroom for several years. Many of my colleagues have actually done controlled experiments and have proven that the students' engagement is far better in a flip classroom than in a conventional classroom. Of course, there are ups and downs. There are papers which I will refer to which you can look at. In India, the distance education was attempted through v-sats and other things earlier. But far before that, Professor Anupray of IIT Kharagpur started a unique experiment in distance education by actually recording video lectures on video cassettes. Those were the cassettes. Taking these cassettes to remote centers where people assembled. The cassettes were played there. And a facilitator will stop the cassette after every 10 or 15 minutes forcing an interaction amongst the participants. And then these interactions were recorded and were reported back to the teacher in IIT Kharagpur, who in the subsequent weeks prepared another cassette recording the reactions to these observations and so on. So it was like a slow speed thing almost like an open university kind of stuff. That was done very early. Professor Ray was ahead of his time. Even today under his leadership, a large pedagogical team has been experimenting with effective teaching and learning. Couple of observations by the pedagogical people. You would have all heard about active learning. Very briefly, it amounts to saying that students must actually participate into whatever we do. The second myth, which I myself became aware of the fallacies when some of my colleagues working in education technology here pointed it out that as teachers we all strive hard to make our teaching better. And that seems to be the single most important agenda for us. And Professor Siddharah here who leads the activity along with Sarnamurti pointed out that you got it all wrong. It does not matter how well you teach. What is important is how well the student learns. And the only mechanism for us to guess or judge how much the student has learned is to assessment an exam. And the exams and assessments are always too late when they come to us and we know some student is weak or some student is very smart. We are unable to do anything about it because 2 to 3, 4 weeks have passed between our teaching and our assessment. And that is how the flipped classroom and the active engagement of students came about. So active learning with students participation. This is again nothing new. More than 30, 40 years ago this was initiated. It is well established through heavy research that this is the best way to ensure that the students learn maxima. Of course good teaching is important but good teaching alone is not sufficient. Now earlier it was not possible to have active learning because the teachers in large numbers were not trained in doing this. But it is possible to use later on as I will mention blended MOOCs to permit this kind of active learning. We will explain the experiment that we are doing in IIT but that is for the later time. The MOOCs phenomena is again nothing very new except for the name. Online courses, online tutoring, online material has been there for ever since the computers came about. Many of you would have heard of the Gutenberg project which initiated open source contents in plain ascii characters for anybody to see. The open source movement in software took roots very early but the open source movement in content particularly in creative content started with the establishment of creative commons and most of the open contents are now released under creative commons license for anybody to use. The MOOC movement as the name stands is about three years old. While there were a few European and American universities which attempted this the major Philip or Bush came when Stanford initiated two companies which came out of their campus. One was Udacity and the other was Coursera. So Udacity and Coursera were two companies which operated from Bay Area of United States. A third company was set up EDX or Education Extended. The difference was these two were regular commercial companies where EDX was a not-for-profit company. It was set up by MIT and Harvard. Please note that while these two first companies emerged in Stanford Stanford and nothing to do with these companies. There were just startups which emerged in this Stanford. But the EDX is a company which is set up by a large grant by the regions of MIT and Harvard. Each gave 30 million dollars to set up this company. And the objective is to take further the MIT Standard Pension of OpenCourseWare and create massive open online courses for the benefit of people. They do not expect this money to be recovered but they expect the company to stand on its own start making revenue. So in that sense it is much different from the other companies. In 2012 when we at IIT Bombay were studying all these effects and we were very clear that such a thing is desperately required for the nation. The reason for our clarity was something else. IIT Bombay has been working on training teachers on large scale. We have a history of about 14 years and we started in this very building our first synchronous interactive course with a few remote centers connected by VSATS. Subsequently we scaled it up to about 10 remote centers and at that point in time TIFAC came to us and said can we see a program to train teachers in large numbers? We ran that program for about 4 to 5 years training 400, 500 teachers at a time. Then the ministry got interested. By this time we had shifted to internet and we have been running programs for training 1000 teachers at a time. We ran those programs for 3 years and more recently in 2012 the ministry gave us a responsibility to train 10,000 teachers at a time. So we have termed this program as T10KT or 10,000 teachers at a time. We have been training these teachers at 300 remote centers where the participating teachers assemble physically. More recently to investigate the use of online program we broke this 2 week workshop into two parts of which one week is conducted online but spread over one month. The participants actually give weekly assignments etc. etc. during that month and then they come face to face for one week. So this is one way of blended books often. Essentially we are doing all of this and we said we need to do two things. One, we need a good platform to scale up this kind of training with blended books offering. And second, can we use this platform to offer meaningful courses to our students across the country. That is how our activities began in 2012. In 2012 and early 13 we had meetings with various people Udacity, Coursera, EDX. There was a charging company in United Kingdom spearheaded by their Open University Future Learn. There were similar small attempts elsewhere but very clearly these three companies were scaling up very rapidly. There is a committee appointed by IIT Bombay to finalize a particular choice of a partner. Two reasons why we chose EDX. One, MIT and Harvard have the same principles as ours and we claim that any content that we create must be free. Interaction, if required, must cost some money and if there is a certification that it must cost a fee. So Open Source content has been the IIT Bombay's philosophy so has been MIT. More importantly, EDX was a not-for-profit company. As I have said elsewhere there is nothing wrong with for-profit companies but we as government funded institutions are more comfortable with not-for-profit. This was one reason why the committee said we will tie up with EDX. The second and equally important reason or perhaps more important reason was that such offerings can be made only on the basis of a platform which has fairly large software and takes anywhere between 2 to 3 years to construct. We were planning actually to start constructing such a platform ourselves but we noticed that EDX had announced in 2012 that they will open source their platform in 2013 June. Now you will agree that if I have 250,000 lines of code written on millions of lines of open source component already working and available then it is much easier to start with that and change it the way you want over a year. So that was another reason why we decided to join with EDX. We joined with EDX in 2013. We agreed that we will offer within a year four courses. Two of them are already running as I mentioned Professor Gaithun and I are running these courses. Two more courses will be offered very soon. Professor Vikram Gadre will be joining us very briefly tomorrow. He will be offering a course on signals and systems and my colleague Professor Ramakrishna will be giving a course on computer networks but that is as far as EDX is concerned. Our courses on EDX are currently meant primarily for the global consumption. So as these thousands of students we do not even know how many students are from India or whatever. But right from the beginning I was very clear that we must use this for the benefit of our school direct. This year in February I was asked to comment on use of MOOCs in an invited talk in a conference on transformation of engineering education where I proposed the use of blended MOOCs and said we must have an open source platform. Very recently the government tasked us with development of an open source platform built starting from EDX and over the three years mature that platform to meet almost all the educational needs of the country. The idea there is that part of the project is to set up a not-for-profit company like EDX which will then continuously drive this activity because there has to be a revenue model for any activity that you do. You cannot perpetuate a system based only on government funding and people would be willing to pay if there are good quality things that are available to them that is the universal experience. So that is the project we started some time ago and that is the context in which Professor Lagu has joined us as an advisor. When we started building this platform we started working by the way almost 6 months ago we actually built a modified platform for what we call the blended MOOCs operation in which let us say Aisar Pune designs a course and that course is taken by IIT Bombay, IIT Guwahati, NIT Suratkal or whatever. Then the actual course contents would be created in Aisar Pune but in each institute like in IIT Bombay there will be a local course copy and there will be a learning management system which will be locally placed. So students here will login into their local thing. Students from NIT Suratkal might have a variation in that course but the main course contents come from Aisar. This was the idea in our blended MOOCs. We tried it only with one institute namely IIT Bombay. So currently one course called CS101 is running in blended MOOCs where the site is called IIT Bombay X for any better name. The course is created there and in the blended part the students see those lectures and they come to the flipped classroom as I made. This is the work that has happened over the last 6 months and that is why we are fairly confident of handling that platform to change it the way we needed or we wanted. February or March we were asked whether MOOCs can be given both in the standard fashion as well as in blended fashion on a large scale to students in it. I first prepared a proposal for deployment in what was known as Techip Colleges. Techip is a scheme for funding engineering institutions and there are more than 200 colleges that are so funded. But subsequently the national mission wanted to enlarge the scope and include all of higher education. That is the genesis of our current meeting here. For some reason most probably because most of your institutions have been involved in creating some kind of open content somewhere. So I got a suggestion from the ministry that can we launch an all India site for MOOCs for Indian students with courses created by to begin with centrally funded institutions. I was told about this decision I think on 24th or 25th of last month. I said who are these people and I need to talk to them. So a video conference was arranged in a hurry on 1st of September. I spoke to some people on 1st of September. There were some more people left. So there was another thing arranged hurriedly on 4th. By this time I had updated my own presentation getting some clarity. 4th of September is when I finally spoke to the Chancellor's and maybe some of you were present there and it was decided that when the site is launched on 25th for the Indian students there shall be presence of several centrally funded institutions and their courses. The ministry wanted the courses to be ready for offer on 25th when the site is launched. I told them in no uncertain terms that please understand our experience. I mean it is not a black magic where a magician takes a rabbit out of the hat and says this is the course. A course requires serious consideration and preparation. I suggested a via media which was accepted by the ministry. The via media is that on 25th when the site is launched the site shall name all the participating central universities as ready to offer courses. So all of your institutions will be there. Along with that list will be the list of courses from each university. However each course will state a start date which need not be within 5 days or 10 days of the launch. Only those courses which are absolutely ready to launch will have a start date preferably around 1st or 2nd October. I have suggested 2nd October being a good date. That is because when you launch the site there is no non-trivial time to students across the country to register, choose courses and prepare for the course. This has been agreed upon and what Liwe that at least the mission director told me is that the central universities should at least decide on the duration of the course and the start date of a course for each course that they will offer and that course must be listed on 25th. That is the reason for this hurried decision making. The modest operandi I suggested is each university to identify number of courses that they would like to offer at least 2 courses from each institution. We have understood the operational activities that happened between EDX and the rest of the university partners. We are actually trying to fashion out an exactly similar kind of setup here. So a relationship between Swayam central administration here in IIT and each of the central university and that is through the notion of a coordinator. In EDX we call them program manager. So as I said Kalpana is a program manager. We will soon appoint a program manager for Swayam. Maybe she will participate or we may need a group here but that is the reason why it is absolutely a must that each one of your central university and institutions must have one coordinate and in case of any issue related to MOOCs offering whether it is related to administration of MOOCs registration whether it is related to any course that is ever offered by your university. It is the coordinator who will be the person responsible for resolving all the issues and therefore I have suggested to Vice Chancellor that the coordinator must be an empowered person. Empowerment in IIT system works differently than in some of the universities but that is for you to sort out. In our case empowerment means that if I am the PI well whatever I do goes. I might take a decision which is unpalatable. In the worst case if I take a decision which is very very bad not like by people my dean has a heart to heart private talk with me.  They will have the backing of the institution. That is how we have functioned in IIT Bombay. I believe many of your institutions would be functioning like that. If they do not I think it is high time we started doing. I will sincerely request you to go back and make sure that this process is followed because we may have to take decisions within 5 minutes of a telephone call. So I was actually I must admit that I was frankly surprised when I got some correspondence saying our VC is not in station. Now doesn't the university run if VC is not there? There is an acting VC. My institute always runs whether the director is here or not. Half the time he is not here. So this is something which I find very unpalatable. An institution or university must run 24 by 7. I am sorry for being very blunt but please take back these precise feelings and ensure that your university functions 24 by 7. That means the decisions are taken. There is always somebody in the hierarchy who will take a call and take the decision. Please. You are most welcome to enter. Sir, I am from Banaras in the University. Yeah. Right now the faculty strength has reduced to half of its bench. So 3000 post 1800. The student strength has increased. So finding a faculty who can offer, design the course and moreover the infrastructure whatever you have created over a six year or three years of time. There is no time because there is no such centralized facility and as far as university system I am not very much familiar with you or not. Tomorrow I may not be the coordinator because the vice chancellor will appoint and he will say that ok Mr. Kumar now you are no more required. Mr. why will be the coordinator? God bless you. God bless Indian education system. No sir. I think Indian education system is much stronger than that. I will submit the following. Like you say I will I can tell you that there is no institute or university here which is running to the full strength of faculty. I don't think that is true with any university. It is not true with IIT Bombay for example. Half of the things. But my humble request is if you scan through the faculty list you will find a few individuals who will be willing to commit beyond their call of duty. Now please such initiatives depend only on our ability to locate and empower such individuals. Otherwise such schemes will not work. That much is I think patently obvious. Do you think all of them have come here only because somebody has appointed them. They are also interested in doing something. Not that they will know anything about it. I think most of us has come here because someone has entrusted that you have to go there. Oh is that true? Second thing please take another piece which is much more serious. We are in a system. Means why I came only from BHO. That is the answer. IIM has come with the three faculties or the reason whenever I was asking to the vice chancellor he said we are the 150 departments. If you take one the next thing in the academic council I will question why you have sent this guy. Why not my department? Every department offers almost 20 to 30 courses. So if it is very good everybody will be willing to offer the course and for BHO it will be very difficult to say that these two courses will be there because the vice chancellor has to answer that why only these two courses or the coordinator has to answer why only these two courses. I can provide an indication of solution. I wonder whether it is going to be a solution. If program coordinators are appointed directly by HRD ministry rather than by the university that will obviate shift opposition within the university. I understand although we are digressing but let me briefly comment. I understand the import of both your observations and questions. The reason I do not like your suggestions sir is because we will lose our autonomy greatly if we permit any external agency including government of India to appoint people. I think this is a call that we have to take ourselves. Secondly, there is a very specific request that has gone out perhaps it has not reached you but if you read my presentation you will understand. What is the objective of these books? The objective of the books is to get the best quality education to the largest number of people. Now amongst the umpteen courses that we have probably the best courses which will fit this bill are described as follows. A, they are meant as introductory courses. B, they are courses which are taken by the largest possible number of students in my own university. And C, I have some of the best recognized faculty members for that course in my institution. If you just follow this simple principle because initially we want to reach out to the largest number of people with the best quality. You know that there are teachers and teachers and teachers. There are very good teachers everywhere but there will be a few who would be recognized not by themselves but by others that they are really good teachers particularly students. I think every university every institution has a set of them. All that you need to do is get such teachers, keep them in mind find out which are the courses which they are teaching. Then from amongst those subjects you find out which are the subjects which are likely to have maximum impact and then find out whether that particular teacher is willing to take the extra efforts of creating a MOOC schedule and offering it. Now this will take some time but how much? Now this I have stated on 1st of September I repeated it on 4th of September. Today we are on 11th of September. One week has passed and if within that week the university or institution has not been able to apply this principle then I have to sadly conclude that either your university does not have such courses which are meaningful to large number of students or great faculty members who are renowned to teach those courses. I refuse to believe this for a minute. It is not possible. Every institution, every university has such courses. Or somewhere it has not been understood that these decisions have to be made quickly. That is the only point. And I would suggest sir a coordinator cannot make these decisions but a coordinator can casual the vice chancellor to make these decisions. Saying these decisions are required. See if I am a coordinator, I do not make these decisions for example I am the PI here but we have a committee of deans director, director and in the worst case we just take that decision convey and we just get an endorsement. So what I would suggest is this is the principle. It does not matter. Whatever has happened, time has passed but at least let us go ahead and do that. My request to you is at least these few lines convey to your vice chancellor today itself by email saying this is an urgent action required identify such people and keep them ready on Monday when we meet them because Monday and Tuesday are the two days when we have to announce the courses. By 17th evening if we do not get the details of your courses we will not be able to put all the digital contents describing your course and university properly on the site which has to be launched on 25th. Now that is our limitation. You get my point. Sir life is not simple. Life is not simple. But my humble suggestion is we have to sort of go ahead and make this happen. What will happen? Perhaps one of our institutions may not be able to come up with such solution. That is the reason why probably ministry has suggested 15 institutions. But I will tell you the minister is herself monitoring this activity and if a university is not there with the courses now there might be some private discussion that will happen with the ministry. So it is and in any case what do we lose? We might make a mistake. We might not be able to put the best course forward right now. Doesn't matter let that course run. This program is to run for decades in future. There will be an opportunity to offer other courses. There will be an opportunity in fact to do a better design for the course that we offer for the first time. No problem. Sir we have to experiment and we have to learn by mistake. But we have to ensure that we make sure that is the only thing possible. So don't worry about it. Even if there is another coordinator appointed day after tomorrow as you say I am sure you will go back and brief that coordinator on everything that you did here and that coordinator having become learned because of this interaction should be able to take decisions in 24 hours. That is the only way hopefully we can proceed. So a very long answer to a short observation. So yeah please. Sir I am just giving you a slightly different picture. We at the university is having a separate institute is known as Institute of Life Long Learning. We are already into this online courses business. Since last 5 to 6 years and we are offering all the major courses which we are teaching in the university in classroom as well as in online platform. But my worry is about the cut off date. We are offering to planning to offer my Vice Chancellor and Dean of colleges directed us to offer economics and commerce. I am economics faculty. So I just want to know in economics there are 20 paper which we are covering in 3 years. Only one paper. Now I understand. One paper in economics and one paper in commerce. Your choice. Your choice. The choice should be something which will maximally help and definitely that will be the essential paper. So now I come back to the confusion that is caused because of a significant difference in terminology used in the IIT system and the university. In IIT system when we say a course it is actually a paper. It is a very fundamental difference. It took me quite some time to recognize that a course in university is actually a program become BSc, BA etc etc.  So I am clarified that when we are talking about offering a MOOC course we are most certainly not talking about offering a program completely as of now we are talking about offering a paper which could be either semester long paper or a year long paper depending upon the nature of the paper. What we have is that the paper that you so select should be amongst the best thought courses in your place and should be as widely meaningful as is possible because the ambition is to reach out to large number of people. I represent Tata Institute of Social Sciences you know and in this we are already offering an introductory course which is called the Foundation Classes on Indian Polity Society of Economy which is offered online to everybody so that's the course that we are planning to offer it out as part of the MOOCs which will come up may be announced on 17th so that's an online program which we already have online and that's going to come up and by course we also mean that it's a paper that is offered in a semester we don't mean a course that is meant that you follow a terminology which is similar to IIT but that is not the standard terminology in the country which I myself realized only we follow the same terminology that we are using. I was seeking to optimize the time in fact can we introduce with courses on Japanese, Chinese, linguistics or the like that is one thing however if they believe that course will have maximum impact and usefulness then there is no we do not know frankly we do not know what these students will like also this is going to be the first time in the country I will tell you the next 6 months will tell all of us a lot more about how things will emerge today we are groping in the dark all of us are starting some of us are fortunate because we have experiences of giving these courses globally or as she says on giving these courses online some of us are fortunate in other way the open university people have been dealing with lakhs of students already but in a different way but for offering these moves in India on a national platform for students I think for all of us the first time in so there will be issues there will be problems and we may in retrospect realize that this was perhaps not the best choice but I would suggest that the best choice is best left to the university because they also have to decide on the basis of how well that course is being offered you see if you offer a course and if it is taught in a very mundane fashion by an extremely bright researcher but who is unable to relate to students and explain things properly then that course may fall flat in the eyes of the students so these are the considerations and these considerations are best judged by the individual universities and people so when you say about Chinese and Japanese you never know there might be a large number of students wanting to learn Chinese here on how you would teach Chinese online but it should be possible to figure that out we were saying that faculty who are appointed for Japanese they fly off to corporate houses for better humiliation and the strengths are left high and dry so that kind of scenario and lot of corporate demand is there for this Japanese and there is discussion in the later part of the workshop where we will discuss on the individual issues and problems but I think you would all agree that by and large these should be the parameters for decision making and most certainly the decision has to be made by the individual institution and the Swayam thing will actually go by whatever decision you make the name that has been chosen by the ministry for this platform is called Swayam we had some unfortunate problems in IIT Bombay when we were building it original plan was to build further on to the blended book site that we had prepared the IIT Bombay X we found that there were lot of core changes that were required and we suddenly found that we would be unable to do that very recently we therefore took a decision to take the latest version of the edx open source open edx platform and fashion it with almost no functional changes into the Swayam platform we have tried to change the look and feel but in the process we have to suppress several pages which actually were remade for our blended books you will agree that when you handle a large software you make a small change somewhere and unless you test the whole damn thing for one week you would not like to release it we had other challenges national mission had planned a cloud in Delhi to host the because lakhs of students will login online unfortunately that cloud is taking some time Delhi IIT has just put up some mini thing for experiment recognizing this in the last one month we have broken our backs and created a mini cloud in this very building you will briefly see it later that will house the Swayam site Professor Lagu pointed out that I should write down very clearly like the Americans do they first decide on an acronym and then figure out the expansion you can see that something very similar has happened but it appears to be an apt this is not just accepted by the ministry but this is likely to be accepted this is something that has been suggested but anyway that is a minor point on which we struggle the Swayam site the temporary site for our training purposes that we have put together is there you will find I am afraid a lot of loopholes in that site in fact as an added request apart from designing this course and apart from checking out whether the course runs properly or not I would request you to go through the entire site that you see look at the pages of the English mistake please help us correct it so you also form a large team of auditors for our first attempt of this site and we would depend on your feedback on correcting whatever it is the desire of the ministry was that when we launch an Indian site it should at least happen in English and Hindi eventually the idea is to have the site accessible in all Indian languages in fact there is no reason why such online initiative cannot be used to supplement the students education even in at the school level or vocational so immediately plans are being made I will tell you the speed I was talking about the speed yesterday I was called by the secretary department electronics to attend meeting where school books by NCRT are being translated into EPUB or HTML compatible books and there is a huge initiative so I suggested why not we start with MOOCs for high school students and immediately plans are being made so you would not be surprised that before our courses fully roll out actually another parallel activity for MOOCs or school education may also start but I digress so here is one request after the tea break when we assemble I will show you the swam site as we see now but please do keep your eyes ears and minds open and be very critical of every small mistake that you see in the site this is not the site which is going out there are other pages that are getting integrated for the final site this version has been released for the training program temporarily but any feedback that you give would be most valuable I have very basic questions who are the expected audience for these courses very similar to the students whom you currently teach in your postgraduate students you teach only postgraduate students which subjects I am from the accounting and finance department I am sure that there will be a large number of MCOM students across the country who might benefit so accordingly this is important feedback for us to design the course I know I mean if you primarily teach postgraduate students it will be silly for anyone to expect that you will offer an undergraduate course that is very correct because you should stick to your own area of expertise and domain that is the whole idea I did not know that would the courses have some prerequisites for enrolment you can say that yes you can of course define the prerequisites these would be in the MOOCs or in the blended MOOCs all courses will run only in the MCOM another thing for the recording part of it the infrastructure like it was pointed out at our home institution we would not be having the infrastructure currently so that has to be created for the course finally to roll out so that is the time that has to be built in the start date and the end date in IIT Bombay we are able to build something very quickly in 3 weeks to 4 weeks time but if you take 2 months for doing that you will get up those 2 months so the infrastructure would be at the home institution for the recording part I fought very hard with the ministry that if you want to roll out then you cannot roll out unless each institution is empowered with its own infrastructure and people so I was to tell you later but I will take 1 minute to inform that I have requested for a budget of 2 crore rupees for infrastructure at each institution which includes 50 lakhs for a small video studio and lab editing lab and 1.5 crores for the other infrastructure including a mini cloud at your own place subsequently you can offer online courses specifically to your own students using the same mini cloud that is one second I have suggested a team of about 20 staff members to be recruited, built and nurtured for a period of 3 years and I have requested for annual salary budget appropriate to maintain these people of course we have taken the budgetary figures from our own experiences appointing people on project but we believe that that will be about a crore rupees per year or something in fact the joint secretary himself said to all vice-chancellors that please feel free to start spending today so your institutions do not even have to wait for any money to come or any further thing to come you are empowered now it all depends upon how you could put things together we will discuss that after the tea break any quick observation I will also it is a good point I will introduce to you a pair Professor Kamishwari and Professor Bhaskar Raman who are preparing MOOCs courses you know where they are they are they are they are they are they are MOOCs courses you know where they are recording in their own offices they use a Camtasia studio you will soon see that it is not necessary for the face of the person to be seen in all recording you record with your handwritten notes or something like that and they are recording in their rooms many of the global courses very well-renowned courses have been so recorded by their faculty in their basement sorry so we should have this facility but we not wait entirely for this so the proposal that I have said which of course once it is approved I will be circulating formal copies where even listed recommended set of equipment for a minimum thing and so on with approximate cost as per our thank you so much


So, this is my first lecture on regression analysis. I would like to introduce myself as Dr. Soumen Maithi. I did my B.Sc. and M.Sc. in statistics and received a PhD degree from Indian Statistical Institute, Kolkata. Currently, I am faculty at Indian Institute of Technology, Kharagpur and Indian Institute of Science, Education and Research, Pune. I am grateful to both the Indian Institute for giving me this opportunity to work on NPTEL project. So, here is the course, a prerequisite. So, I would expect the viewers or specially the students, you know, to know basics of probability and statistics and statistical inference. So, more precisely, you know, I would like the viewer to know the discrete and probability, discrete probability and also continuous probability distributions and say point estimation, interval estimation and also, you know, testing of hypothesis. So, this course is divided into several topics or module. So, here are the topics. It is a simple linear regression, multiple linear regression, selecting the best regression model, multicollinearity, model adequacy checking, test for influential observations and then, you know, transformation and waiting to correct model inadequacies, dummy variables, polynomial regression, generalized linear models, non-linear estimation and regression models with autocorrelated errors, measurement errors and calibration problem and finally, we will be solving some problems. So, I will have some sort of tutorial classes and I would be basically following these two books. The first one is Applied Regression Analysis by Draper and Smith and the second one is Introduction to Linear Regression Analysis by Mont-Goummery, Electric and Binding. So, here is the content of today's lecture. So, today basically, you know, I will introduce what is regression analysis and then, I will be talking about simple linear regression and least square estimation of the parameter. That means, the regression coefficients. So, let me talk about what is regression analysis. So, regression analysis is a statistical tool for investigating the relationship between a dependent variable and one or more independent variable. Just now, I will give an example to explain what I mean by dependent variable and independent variables and regression analysis is widely used for prediction and forecasting and it has application in different fields like economics, management, life and biological science, physical and chemical science, engineering and social science. So, here is the example. I told that, I will give an example to explain what I mean by independent and dependent variable. So, I said that regression analysis is a statistical tool for investigating the relationship between a dependent variable and one or more independent variable. So, consider this example. Suppose, you are marketing analyst for Disney toys and you gather the following data. The first column is advertising cost and the second one is sales amount. So, here this is a and what we want is that, what is the relationship between the sales and advertising cost. So, here you can see that the amount of money we want to spend. That is sort of controlled variable. You can decide how much amount of money you want to spend for advertising, but the sales amount is not a controlled variable. You cannot control the sales amount. So, the sales amount is a dependent variable. It depends on advertisement cost. Not only maybe this is one factor, but it depends on the amount of money spent on advertisement. So, this is a dependent variable, but the advertising cost is an independent variable. Also, we call it controlled variable. You can control it. So, usually, so I hope that you understood the difference between the independent and dependent variable. So, usually this variable which is independent, this is denoted by X and X is a regressor variable or also we call it independent variable, whereas the sales amount, we do not have any control on sales amount and this one is this type of variable is denoted by Y and Y is response variable and also we call it dependent variable. So, as I told regression analysis is a statistical tool for investigating the relationship between one dependent variable and one or more independent variables. So, here I mean the whole objective of this course is to find the relationship between the variables, one response variable and several independent variables. Let me talk about scatter plot next. So, here these are the same observations. I have been given a set of observations say X i, Y i. So, X i stands for regressor variable and Y i stands for response variable and I have five observations like X 1, Y 1, X 2, Y 2, X 3, Y 3, X 4, Y 4, X 5, Y 5 and the scatter plot is basically obtained by plotting this data on X, Y plane. Formally you can say that scatter plot is a mathematical diagram to display values of two variables for a set of data. So, now I will explain the scatter plot for this Disney toy data. So, the first observation X 1, Y 1 is plotted here. The second observation is X 2, Y 2. So, that is plotted here. I should say that usually in regression analysis the regressor variable is plotted along the X axis and the response variable is plotted along the Y axis. So, these two points corresponds to this two data point and then 3, 2 is here and I have next 4, 2 here and then 5, 5, 4 here. So, this is the scatter plot, corresponds to the data for Disney toy problem and this scatter plots are used to investigate the possible relationship between two variables. So, the scatter plot are used to investigate the possible relationship between the variables. Now, if the scatter plot indicates sort of linear relationship between the variables. So, in that case we need to go for linear model, but if the scatter plot indicates sort of non-linear relationship between X and Y, then we need to go for like maybe quadratic feed or the cubic feed or the higher order polynomial feed and looking at this scatter plot, I feel that you know this scatter plot indicates sort of linear relationship between the response variable and the regressor variable. So, for this Disney toy data we would go for linear model between X and Y and the objective of this module is to study you know how to fit linear relationship, more specifically simple linear regression for given a response variable and one a regressor variable. So, now we will talk about simple linear regression. So, simple linear model regression model is a model with a single regressor X that has a linear relationship with a response. So, the simple linear regression model is a Y equal to beta naught plus beta 1 X plus epsilon, I will explain it. So, here you know that Y is a response variable and Y is a regressor variable, beta naught is called intercept, beta 1 is called slope and epsilon is a random error. Before going into the detail of this one, I want to mention that one more thing like just recall the Disney toy example, there we have one variable that is the advertising cost and X stands for advertising cost, the other one is sales amount. So, I told that X is a controlled variable.  So, X is not a random variable, whereas Y is a dependent variable, you cannot control the sales amount. So, Y is dependent variable, it depends on regressor variable and it cannot be controlled. So, Y is a random variable and X is not a random variable, it is a control variable, you can say it is a deterministic variable or mathematical variable, but X is not a random variable, Y is a random variable. So, come back to this simple linear regression model, Y equal to beta naught plus beta 1 X plus epsilon. So, what is the meaning of this one is that for a given X, that means given advertising cost, the corresponding observation Y, that means the corresponding sales amount consists of the value, consists of the value beta naught plus beta 1 X plus an amount epsilon. So, it says that given the advertising cost, the corresponding sales amount consists of the value beta naught plus beta 1 X plus some error component, I mean that is a variable component. So, next we will make some basic assumption on the simple linear model, we now make some basic assumption on the model. The model is Y i, Y i, Y i, Y i, Y i, Y i, Y i, Y i, equal to beta naught plus beta 1 X i plus epsilon i, for i equal to 1 to n. So, before I wrote Y equal to beta naught plus beta 1 X plus epsilon, now I am writing the model, the same model for the ith observation. And here I said that this is a random error component. So, what we assume that the first assumption is that epsilon i is a random variable with 0 mean and variance sigma square, which is 0. So, what you are given is that you are just given a set of observation X i, Y i for i equal to 1, that is all. And from the scatter plot, if you see that the relationship is linear, then you are going to fit a simple linear regression model. And you are making some assumption on the model. So, epsilon i, the error term is a random variable with 0 mean and variance sigma square, which is unknown. So, that means, expectation of epsilon i is equal to 0 and variance of epsilon i is equal to sigma square. The second assumption is that, this is very important part. The second one is the epsilon i and epsilon j are uncorrelated i not equal to j. That means, the covariance between epsilon i and epsilon j is equal to 0. The third one is that epsilon i is a normally distributed random variable with mean 0 and variance sigma square. That means, assuming that epsilon i follows normal distribution with mean 0 and variance 0. Now, what you can see that this epsilon i's are uncorrelated and they are normally distributed. So, under this normality assumption, now this epsilon i's are not only uncorrelated, they are independent also. So, these are independent. So, what you can see is that epsilon i is the consequence of this one in terms of the response variable y i. So, what we are basically assuming is that, let me write down. So, I said that y is a random variable and x is a controlled variable. It is a deterministic variable. It is not a random variable. So, and we made several assumption on epsilon i. Now, what is the consequence of this assumptions on y or in terms of say y? So, y i is equal to beta naught plus beta 1 x i plus epsilon i is equal to beta naught plus beta 1 x i plus epsilon i. From here, I can write expectation of y i is equal to expectation of beta naught plus beta 1 x i plus epsilon i and this is equal to beta naught plus beta 1 x i just plus expectation of epsilon i, which is equal to 0. And what is the variance of y i? Variance of y i is equal to variance of beta naught plus beta 1 x i plus epsilon i, which is equal to variance of epsilon i because these are not random variable. So, which is equal to sigma square and also finally, we assume that epsilon i follows normal distribution with mean 0 and variance sigma square and they are independent and the consequence of this one in terms of the response variable y i is. So, y i follows normal distribution with mean 0 sorry with mean beta naught plus beta 1 x i and variance sigma square and they are also independent. So, the assumption on the error term like epsilon i having expectation 0 variance sigma square and follows they are uncorrelated and they are uncorrelated and epsilon i follows normal distribution. So, finally, epsilon i is following normal distribution with mean 0 variance sigma square and they are independent. So, the consequence of that in terms of response variable is that y i follows normal distribution with mean beta naught plus beta 1 x i and variance constant variance sigma square. So, we are assuming that the ith observation is from normal distribution with mean beta naught plus beta 1 x i and the constant variance sigma square. So, given a set of data you need to be very careful about whether your data set satisfy this basic assumption or not. But, if the data set is not satisfying the basic assumptions then you cannot go for the usual least square fit and all these things. I will be talking about those things maybe in this class only. So, there will be a topic called model adequacy checking. So, that talks about given a data set you know while fitting a simple linear regression model how to check whether the basic assumptions are true or not. So, we have to wait for that model adequacy checking topic. So, let me once again you know graphically say what is the how this situation I mean how this assumption is illustrated in this figure. So, we made the assumption like epsilon i follows normal distribution with 0 means and variance sigma square and they are independent right. And the consequence of that in terms of response variable is that y i follows this. So, what we are assuming is that this is my x 1 y 1 data this is x 2 y 2 this is x n y n and this line is x 2 y 2 this is x n y n and y equal to beta naught plus beta 1 x. So, this you can put also i anyway. So, the first situation like I mean the assumption in terms of y is you know graphically illustrated here. So, it says that the i th observation or the i th value of the response variable y i that is coming from a normal distribution with mean beta naught plus beta 1 x i and variance sigma square. So, this is the normal so x y 1. So, this is the data x 1 sorry x 1 y 1. So, y 1 is from normal distribution with mean beta naught plus beta 1 x 1 and variance sigma square. So, this is from this distribution this is a normal distribution and x 2 is again from normal distribution with different mean with mean beta naught plus beta 1 x 2 and variance constant variance sigma square. I mean this part is you know it is it is necessary that you know you understand this part or the basic assumptions we made. So, assuming this means you are assuming that the response variable follows normal distribution and the i th observation is coming from normal distribution with mean beta naught plus beta 1 x i and constant variance sigma square. So, next we will move for least square estimation of the parameters. So, we talked about we know what is the simple linear regression model y equal to beta naught plus beta 1 x plus epsilon. So, least square estimation of the parameters. Means estimating the regression coefficients beta naught and beta 1. So, this is called intercept and this is called slope and fitting a simple linear regression model is nothing but estimating this regression coefficients. So, it says that the parameter beta naught and beta 1 are unknown and must be estimated using the data. So, what you are given is that you are just given a set of observations n observations and you have to fit if the scatter plot indicates that you know there is linear relationship you can go for a simple linear regression fit and also in the regression analysis you know the starting point is generally fitting linear model. So, suppose well so this is the scatter plot for the Disney toy data and we have to estimate the regression coefficients that means we have to fit a straight line. So, this is given for the given data suppose the fitted model is y hat which is equal to beta naught hat plus beta 2 hat into x. So, this is the fitted line and you can see that I have drawn two lines the same scatter plot this is one straight line say suppose this is my fitted model for this scatter plot or for this data and this is another fit. Now, which one is better whether this one is better or this one is better or this one is better. So, this one is better well. So, I will come back to this slide again let me write one important thing the line fitted by least square is the one that makes the sum of square plus the sum squares of all vertical discrepancy as small as possible. So, this is the now main idea behind the least square fit the line fitted by least square technique is the one that makes the sum of square of all vertical discrepancy as small as possible. So, what is the meaning of that? So, what the least square technique does is that it fits a line such that what I mean by this vertical discrepancy this is the vertical discrepancy for the fourth observation. So, for the fourth observation this is x 4 basically this is x 4 y 4 right x 4 y 4 is equal to 4 2. And suppose this is the fit this is the fitted line y hat is equal to beta naught hat plus beta 1 hat x and then this point is nothing but x 4 y 4 hat. So, the vertical discrepancy is nothing but let me write that as e 4 that is called residual for the fourth observation. So, e 4 is equal to this distance that is y 4 minus y 4 hat. So, this is what the what we mean by the vertical discrepancy. And we what the discrepancy least square estimation or least square technique does is that it fits a model such that this e i square for i equal to 1 to n in general, but here it is 1 to 5 this is minimum. So, in order to say you know which fit is good whether this is good or this one is good. So, what you do is that you compute this e i square this is called residual sum of square this is s s residual.  And what the least square estimation does is that it computes it provides a fit which has minimum s s residual. So, I hope that you know you understood the basic and very nice and you know natural idea behind the least square estimation. So, we estimate beta naught and beta 1 so that the sum of square of all the differences between the observation y i and the fitted line is minimum. So, the meaning of this one is that you compute all the residuals e 1 e 2 e 3 e n and then you come then this beta naught and beta 1 are estimated. So, that this summation e i square i equal to 1 to n is minimum. So, I will write this. So, you estimate beta naught and beta 1 so that the sum of square of all the difference between the observation y i and the fitted line is minimum that means s which is nothing but s s residual sum of square residual which is equal to e i square i equal to 1 to n which is nothing but y i minus y i hat square which is nothing but y i minus beta naught hat minus beta 1 hat x i square is minimum. So, you have to estimate you have to find this beta naught hat and beta 1 hat which is beta naught hat is the estimate of beta naught and beta 1 hat is the estimate of beta 1 such that this is minimum. So, the least square estimator of beta naught and beta 1 that is beta naught hat and beta 1 hat they must satisfy the following two equations you differentiate s with respect to beta naught and at the point beta naught hat beta 1 hat and beta 1 hat. So, this is so let me just write down what is s s is equal to summation y i minus beta naught hat minus beta 1 hat x i square. So, this is what the s is so you find beta naught and beta 1 such that this is minimum. So, this one is equal to the partial derivative of this one with respect to beta naught is minus 2 y i minus beta naught hat minus beta 1 hat x i equal to 0. So, this is one equation and the other one is partial derivative of s with respect to beta 1 at the point beta naught hat beta 1 hat. So, now we are differentiating with respect to beta 1 so that is equal to minus 2 summation y i minus beta naught hat beta 1 hat x i into x i right. So, this is equal to 0. So, these are called these two equations are called normal equations normal equations. Since there are two unknown parameter you will get two normal equations and you can see that this normal equations are independent right. So, you can uniquely fit beta naught and beta 1. So, the estimator beta naught hat and beta 1 hat are solution of the equation summation y i minus beta naught hat minus beta 1 hat x i equal to 0 and x i into x i into x i into x i into x i into x i into x i. So, you have two independent normal equations and from here you can estimate beta naught hat and beta 1 hat. So, we will be doing that let me start with this one. So, what the first equation is summation y i minus beta naught hat minus beta 1 hat x i equal to 0. So, from here I can write that summation y i minus n beta naught hat because this sum is over from 0 to from 1 to n minus beta 1 hat sum x i i is from 1 to n this is equal to 0. So, then n beta naught hat is equal to 0. So, this is equal to 0. So, sum over y i minus beta 1 hat summation x i and from here I can write that beta naught hat is equal to y bar minus beta 1 hat x bar. So, of course, where y bar is equal to summation x i x bar is equal to summation x i by n and y bar is equal to summation y i by n. So, this involves beta 1 hat. So, we need to estimate beta 1 hat also I mean we need to find the beta 1 hat also. So, let me start with the second normal equation that was summation x i into y i minus beta naught hat minus beta 1 hat x i equal to 0. This is beta naught hat minus beta 1 hat x i equal to 0 and just know what we obtained is that beta naught hat is equal to y bar minus beta 1 hat x bar. So, I can plug this one here. So, what I will get is that x i y i let me write one more line minus y bar minus plus beta 1 hat x bar minus beta 1 hat x i is equal to 0. So, from here I can write that x i into y i minus y bar is equal to minus beta 1 hat x bar minus beta 1 hat sum over x i minus x bar I hope you understand this one. So, from here I can write that my beta 1 hat is equal to sum over y i minus y bar into x i by sorry I missed one x i here by sum over x i minus x bar into x i. So, this can be written as sum over y i minus y bar into x i minus x bar by summation x i minus x bar into x i minus x bar by summation x i minus x bar into x i minus x bar. So, this is x i minus x bar square. So, what I have added is that I have added a term here I can prove that see because of the fact that I can prove that y i minus y bar into x bar is 0. So, let me just now prove that this is equal to sum over y i x bar minus summation x bar y bar and if I write y bar is equal to 1 by n summation y i. So, summation y i I can write as n into y bar. So, that is n into x bar into y bar minus this sum is from 1 to n and it is independent of i. So, n into x bar and y bar. So, this is 0 also we will use the notation that this is equal to s x y by s x x. So, whole whole whole whole whole whole whole whole whole whole whole what we got is that finally, we got that beta naught hat is equal to y bar minus beta 1 hat x bar and also we got that beta 1 hat is equal to summation y i minus y bar into x i minus x bar by summation x i minus x bar whole square. So, we have learnt how to fit a simple linear regression model given a set of observations say x i y i for i equal to we know how to fit a simple linear regression model like y i is equal to beta naught plus beta 1 x i plus epsilon and here are the least square estimators beta naught hat and beta 1 hat and in the next class we will be talking about several properties of this least square estimators and it can be proved that these are the best linear unbiased estimators using Gauss Markov theorems. Thank you.


Welcome to class 10 in topics in power electronics and distributed generation. In the last class we are looking at the issues of fault coordination and we looked at the case where you had a existing feeder and then distributed generation source was added to the feeder and then we looked at what would what is the resulting system. So, we saw that in general in a distribution system the fault current levels can actually increase decrease or stay the same. So, if your fault current level changes during the addition of a distributed generator source then there is a possibility of miscoordination between your upstream and downstream device. Because of this change in the current level and you cannot uniformly say that the current level is always going to increase at the protection point it can actually go in all three ways. So, if you look at then in the case of your parallel connected circuit breakers suppose you add a DG source and then you have a parallel branch which is going into a neighboring facility and that could be a situation similar to this particular circuit breaker too. We saw that the current that needs to be handled by this parallel breaker can potentially go up. So, in parallel with the DG system there can be numerous breakers because you have many loads many possible branches that are there in parallel and there is a possibility that the current level may go above the interoperating of that particular parallel breaker. In which case the that particular device need to be replaced with a higher rated device and then the issues becomes more complicated because the parallel breaker may not be owned by the person who is introducing the DG and then you have the question of who will bear the upgrade cost is it going to be the electricity provider the utility provider or the person who is installing or who is the owner of this parallel branch protective device. So, there are questions like that which arise. So, you also have the situation where say because of the change in current level a recloser which might have been say the coordination settings might have been done to obtain few saving strategy and because of the change in the current levels with the addition of DG now the few saving strategy may not work. So, now there is a direct cost impact on the utility because of the addition of the DG source. Also for example, if you have a sectionalizer sectionalizer is supposed to operate with a upstream recloser. So, if you look at the previous example suppose CB1 was a recloser and CB2 was a sectionalizer then essentially the sectionalizer would open for a case of say fault at bus 4 suppose you have a fault at bus 4 then we saw that essentially what the recloser along with a sectionalizer would do is that the sectionalizer would try to clear a temporary fault over here making use of the characteristics of the recloser. But, now if you have a parallel DG which is sending current through the recloser the recloser will now have to interrupt a non zero current where it was designed to interrupt a zero current level. Also if the current that the DG is providing is now higher than the setting for its counting then the counting of the sectionalizer might get affected. So, there is a possibility that as the sectionalizer might mal operate or might operate at non zero current. So, for a variety of these reasons you would need to address this particular issue and one possibility is to address the issue of miscoordination between protective devices you could think about upgrading your protective devices from the simple time over current type of characteristics to something more complex like what is being used in transmission systems or in meshed network where you can have multiple sources and then you try to protect sections of the network by things like directional relays distance relays etcetera. So, that would be one possibility but then that drastically increases the cost which may not be acceptable for a distribution system. Then the second another possibility is say to increase say to operate your distributed generation source. So, that you rapidly disconnect the DG for any fault on the distribution system. So, in this particular example that you have for any fault in any part of this particular system essentially you need to rapidly operate CB3. So, that you disconnect CB3 rapidly in response to a fault then the feeder goes back to the traditional distribution system operation and then the previous old setting for coordination would work. But, there is always a problem in situation such as this that you have to operate the CB3 extremely rapidly which means that it is more prone towards opening under nuisance conditions. It is circuit breakers have finite number of opening and closing before it needs servicing. So, you would need much higher maintenance for the circuit breaker. So, just being able to rapidly open the breaker may not be again sufficient in all situations. So, another way of addressing this particular situation potentially is instead of having the traditional say voltage behind impedance type of DG. If you can operate your DG such that you have it controlled more like a current source where now your current injection level during fault is almost a load current level then your contribution of fault current from your DG is now much lesser. This is what is more typical in a poly electronic type of DG where often if you look at existing poly electronic systems you have some disturbance coming from the grid your power converter might actually just trip off. So, many times the contribution coming from your power converter might be extremely small. So, if you could have a poly electronic DG rather than a machine type of DG then that might address this issue to some extent. But again this has a cost impact I mean the cost of poly electronics is higher than cost of machines. So, ideally then the challenges can you make the cost of a power converter as low as that of a machine. So, you can see that the variety of challenges in when you connect DG distributed generation source to the distribution system. And there are possible solutions, but it has to be addressed in a clean manner. And many of these problems are actually non-technical like who is the owner of what particular device which is not a clear technical problem. So, you will have to actually look at it in from multiple factors rather than just a technical way of looking at the electrical system. . Now, we will look at any another aspect of distribute the distribution system important again it has implications when DG gets connected and that is grounding. So, if you have any electrical system you would ground it and the primary objective of grounding of a system is actually human safety. Someone should not touch electrical system and get a shock you should not get electrocuted. So, human safety is a very the primary objective if you touch a cabinet you should not get a shock. So, you should have low touch potential and you also want to prevent overheating of conductors after you have a fault you can have over current. And if the current level stays high for a longer duration and the conductors would heat and you can have electrical fires. So, to prevent electrical fires is a important criteria. And to prevent may both that high touch potential lasting for long duration and for ensuring that you do not create overheating you need to actually rapidly disconnect the fault. So, even for there is a short O potential for a fault duration if that duration is very small then the resulting damage can be quite small. Also, another important objective is say prevention of arcing when you have a fault there is always a chance that you might have vaporization of metal very high current levels you have a lot of energy in the arc. And people who might be standing near the arc might get severe burns electrical burn is a very severe category of burn. And to prevent that you want to actually ensure that the energy in the arc is kept minimal. So, you want to prevent electrical the energy in arc faults. There are other factors that are important for example, rapid identification of the fault and its clearance is a important aspect for many equipment ensuring the continuity of electrical service is a important factor. So, if you have a fault in one equipment and if the equipment is critical and if the equipment goes down there might be consequences of shutting down that particular electrical section. So, you might have critical equipment where even after a fault you might need to ensure continuity of a service. So, sometimes the need for continuity of service might conflict with the need for rapidly clearing the fault after identifying it. So, you need to have a definite strategy of what exactly is more important for the portion of network that is being considered. Also, if you look at equipment during fault there is a chance that the phases which are not faulted would potentially experience over voltage. And over voltage can cause damage to insulation and you want to ensure that you do not have over voltage because of the way in which you have grounded. Your grounding also has an impact on equalization of voltage between multiple equipment. Suppose, you have especially when you are looking at communication computer networks etcetera you have equipment in one location trying to communicate to another particular location and you want to ensure the integrity of signals. So, how you ensure what is reference at the two locations would become an important factor for ensuring equalization of voltage and the integrity of communication.  So, overall grounding is a important aspect of any system that you are building or how you operate the system this is a important factor. So, if you look at the grounding of a distribution system you can think about what are the possibilities of at the source end. At the source end you can have a ungrounded system and when you have a ungrounded system you might have a y section of a transformer which is with a insulated neutral or you might have a delta connection at your source. So, ungrounded is one possibility you can also say have solid grounding essentially it means that you can have a y transformer with the neutral solidly connected to ground can have a zigzag transformer. So, with different possibilities you can have very no intentional impedance added between your neutral and the ground is what is a solid grounding is. Then you have the third option which is impedance grounding and when you connect a impedance between your neutral and ground then the question is what is the impedance that you are connecting there are two possibilities one is you have a high impedance or you have a low impedance and then there are further two possibilities whether you are connecting a resistance or a reactance. So, you can have a high resistance grounding low resistance grounding. So, or you can have a high reactance or low reactance grounding high reactance grounding is not that common there are some special cases where people talk about resonant grounding etcetera. But that is only for special cases where you have a lot of control over the parasitic capacitance to ground the common impedance grounding methods or high resistance or low resistance or low reactance. So, we will look at the case of when you have a insulated or ungrounded system and we will assume that you have a delta y transformer and the y point is not grounded and say you are feeding two loads load L 1 and L 2 which in turn are connected through delta 1 delta y transformers and say you have transformers x 1 and x 2 x 2 and x 3 and say you have a fault to ground occurring on the feeder say with fault impedance Z f and you want to look at what would be the result of such a scenario in this particular system and we are looking at a single line to ground fault which is a common type of fault that can occur in the system. So, to analyze this we will draw the sequence network to analyze this particular fault. So, you have your positive sequence network. So, in this particular case we had assumed that we have a transformer with 5 percent reactance and the zero sequence network is actually now open circuit because it is ungrounded. So, if you look at the there can be no fault current in this I f should be zero in this particular case. So, you have V plus is equal to 1 per unit and V minus is 0 and V 0 is minus V plus minus 1. So, then if you look at your phase voltages using the sequence transform. So, your V a is 0 which is what you would expect because that is the phase that has the fault V b is root 3. So, you can see that phase b and c conductors c line to line voltage on a with respect to ground and but if you look at the loads L 1 and L 2 the loads L 1 and L 2 would not see any disturbance because it is connected through transformers and the transformers block the zero sequence voltage. So, the loads do not see any disturbance, but the feeder would see some the phase b and c would see a increase voltage voltages. And the amount of fault current is actually 0 which means that it can actually continue to operate under that condition for actually a long duration of time. The main concern of this particular situation is that the phase which is which has the fault would typically have some degree of arcing which means that whatever conductor got grounded would have arcs and that arc would periodically act like a switch which is on or off depending on whether there is at the nature of the arcing.  And then essentially you would have higher phase voltage which can potentially now be much higher than the root three times the voltage that we saw and you can damage insulation. So, people almost never use a ungrounded systems what would be more common is to use a high resistance grounded grounding system where the resistance would help dampen out the oscillations. And you provide the required damping and also one need to keep in mind the type of over voltage protective devices that are used in the system suppose you have surge arrestors which are rated for line to neutral line to ground voltage of some with some particular margin. Now, if it is seeing 1.7 times the nominal voltage then you need to actually on a longer term basis you need to ensure that your over voltage protective devices are rated for the appropriate level of voltage. The second thing to consider is if you have one fault say occurring on phase A and now you have a second fault now occurring on phase B or phase C or maybe even at a neutral then the resulting fault would be now having much higher fault current levels because it acts like a phase to phase fault and then the over current would immediately trip the breaker. And you do not want to ensure the you want to ensure that the fault which has occurred first is attended to at some particular point before the a second fault occurs in such a system. So, you would like to have some sort of a monitoring system which monitors the voltage and ensure that there is a good availability of I mean one of the attractive features of this particular system was that even after the first fault you had a continuity of service to load 1 and load 2. So, with high impedance grounding people try to make use of the ability for the system to be both available after the first fault. But at the same time you need to have insulation monitoring and residual current measurements etcetera to ensure that some maintenance is being done. So, that before the second fault occurs the first fault is identified and cleared. If you look at the grounding of a typical system one should also not just look at the grounding of the source alone you have to look at both grounding at the source and at the load. This is important because if you look at physical distribution system there is a geographically the source might be a distribution transformer at the end of the street and your loads might be your individual houses all along the street. So, there is a big separation between where the load is and where the source is and unlike say if you have a printed circuit board your power supply and your load on that particular printed circuit board is on the same board and geographically much closer together in distribution system the distance between your source and the load is actually much larger. So, you have to think in terms of both grounding at the source and grounding at the load. So, based on the grounding at the source of the load some of the common ways of nomenclature or configurations for the grounding system one is a i t system where the first word i refers to insulated and the word t refers to tera. So, your source is high resistance grounded or the neutral is insulated from ground and the load frame is connected to earth or tera that is one possibility another possibility is the source is connected to tera through no intentional impedance and the earthing from the source is now your neutral point is distributed to the load and this is this configuration is called a T n configuration also you could have power earths earthing points both at the source and at the load this is called a T t configuration where both the source and the load is connected to tera. So, these are important especially considering the secondary distribution network. So, this is the low voltage network which comes from your distribution transformer which might be 11 k v to 415 volts and then coming to the individual homes or establishments and an example of ungrounded secondary distribution network is a i t network where you can see that the neutral is insulated from the ground and the loads have their own local grounds. So, you can have say power earth for say load 1 and 2 might share a power earth load 3 might have its own power earth at a different location. So, these are essentially grounding rods that are connected to the ground. So, essentially load 1's cabinet is connected to power earth load 2's cabinet is connected again to power earth load 3's cabinet is connected to its power earth there are 3 wires plus the neutral from your transformer going to the load. So, your loads might be 3 phase or single phase. So, in this particular situation this corresponds to the situation where if you have a fault say on a line to ground basis then you can potentially continue to operate the loads as we saw in the ungrounded system. But say suppose instead of the fault occurring at this particular point you could also have a situation where say the fault occurs say in load 1 and in which case you need to ensure that the load 1 is disconnected load 1 is disconnected before because there might potentially be a second ground fault may be at some other point in the system. Now, if you want to disconnect load 1 because there is no high current after the first ground fault you need to ensure that you need ground fault detection capability at each particular load. And not just that your circuit breaker should now have the capability to disconnect all 4 conductors. So, it is not a just 3 pole circuit breaker it is a 4 pole type of circuit breaker because even if you disconnect say the 3 phases r y and b for load 1 and say you have a fault in the load where phase r is connected to the cabinet in load 1. Suppose you now have a subsequent fault in load 2 that particular fault can actually propagate through the neutral in through load 1. So, to ensure that the load 1 is fully disconnected you have to actually also disconnect the neutral. So, the type of circuit breaker that you would use in IT network would be different from what you would use in a some other type of grounding network. So, the next possibility is say instead of having an insulated or a ungrounded source you could actually have a solidly grounded source. So, this is an example where you have a delta y transformer which is acting which the y is now your source and the neutral is now connected to ground through no intentional impedance. And for our analysis we will assume that the source side impedance is 0 and whatever is limiting the current is essentially the transformers leakage. And suppose you have a fault between any phase to ground will assume say phase to ground solid fault. Then essentially in this particular case we can then look at what is the resulting voltages and currents. So, we will assume a source through a circuit breaker. So, your sequence network is essentially so your I f by 3. So, your fault current level for a single line to ground fault is 20 per unit. In this particular case we have assumed that your source impedance is 0 in which case your 3 phase fault current and your single line to ground fault current is actually going to be the same. If your source impedance is not 0 if then your single line to ground fault current level with a delta y transformer with the y which is solidly grounded the single line to ground fault current can actually be higher than the 3 phase fault current. Because the 0 sequence impedance back at the source is not captured in the 0 sequence network. So, sometimes people might consider adding neutral grounding impedance for the transformer even in this particular case. But to look at the analysis of this particular situation we can then look at what is the resulting voltage your V plus. So, your V plus turns out to be 0.67 angle 0 your V minus. So, we can calculate our phase voltages V a is 0. So, we can see that in this particular case when you have solid grounding your phase B and C does not see over voltage. But you can see that your fault current level is quite large and in our example it is 20 per unit can cause arcing faults. . However, you can see that even though the fault current is quite large the current level is large implies that your circuit breakers would act on an instantaneous basis. So, the duration of fault current would be shorter. So, your fault is cleared on a short time. So, the thermal damage may not be that bad, but you can have arcing for your short duration when there is a high current flowing when there is a single line to ground fault. So, if you look at then an example system where you have solid line to ground I mean solid grounding of the source an example is the T n network where the y point of your transformer is solidly connected to power earth and neutral is then distributed to all the loads. So, the neutral is now expected to be at low voltage at the ground voltage because it is connected in a tight manner to power earth. So, your loads load 1 and load 2 cabinet is also now connected to the distributed neutral. So, you have a situation where you can say for example, you might have a fault in load 1 and you now have a large current flowing between your phase conductor and returning back to the source through this neutral wire and the current level is quite high and one thing is it is it can be quite difficult to distinguish between now unbalanced load current flowing through the neutral and ground fault current which is now coming through the neutral because ground conductor is being shared. Also, if you look at the network suppose you have a considerable say distance between your source and your load then your impedance of the neutral conductor might be not negligible which means that if you have a high current which is now flowing through this particular neutral conductor then person who is actually having his hand on say a cabinet will see a high touch potential because and the touch potential is now seen across the network. But it is typically for a short duration because we saw that the current level is quite large which means that your instantaneous strips would operate. So, for a short duration you could have elevated touch potentials. So, one issue was this neutral current is not being differentiated from your load current. So, one way of getting around that particular problem is to have something called the TNS grounding where the neutral and the power earth are now separated as conductors.  So, this is TN with separate ground and neutral conductors here it is now possible to differentiate between a case of unbalance and ground current. But here again you can see that immediately the cost is high for distributing a power in 3 phase now you have 5 conductors. So, then you can say maybe you can have some combination of this where maybe for some distance you will have a common say conductor and further behind it you can have separate conductors for your network. So, you might have somewhere this is called a TNCS network where there is TN combined for some section and then separate for the rest of the section. So, as long as the fault current is being monitored say at different locations where you have the separation then it is possible to look at the sum of the currents in your phases and along with your neutral to identify whether there is a ground fault. But then you do not have to distribute your 5 conductors all the way it is combined to some extent and then it is separated. In this particular case unlike the case where we saw in the IT type of distribution networks it is now sufficient to have your circuit breakers on a 3 pole basis because of your solid grounding each phase any of the phase which would have a ground fault would see the elevated current and then it would get disconnected from the source and your neutral in way is solidly connected to ground. So, a 3 pole circuit breaker would be sufficient in a TN type of network unlike the IT type of network. So, next possibility of having a grounding in your network is to have a impedance between your neutral and ground. So, you intentionally add a resistance or a reactance to the particular network and then we look at the resulting situation what would happen in this particular case. So, in this particular example we look at a case where you are adding a reactance of J point 1 J point 1 per unit. So, the reactance is quite small. So, this is low reactance type of grounding which means that the ground current in this particular case is high. You might select the reactance that it is high just high enough to trigger your instantaneous protections, but it is not too high that you might have severe arcing damage. So, you get the advantage of the high currents at allowing your device protective devices to trip rapidly, but at the same time the currents not becoming so large that you would have dangerous arcing at the point of fault. So, your fault damage can be reduced in this particular case. So, if you look at the resulting sequence network. So, we look at impedance grounding and we look at an example of J point 1 per unit as we mentioned. So, if we look at what would be the resulting sequence network when there is a fault. So, the positive sequence network is this is the negative sequence network and we will assume Z f to be 0 and the current here is I f by 3. So, you can see that your fault current level has come down when we had solid grounding it was 20 per unit. Now, I f is 6.6 per unit and then we can look at the resulting voltage your v plus and then you could calculate what your phase voltages are and that works out to be nearly 0 v b is works out to be about 1.45 per unit at angle minus 143 degrees v c is. So, you can see that the resulting voltage levels is somewhere in between what you would get in a solid grounded situation and a ungrounded system. So, in a ungrounded system you have 1.7 per unit voltage here in a solid grounded case you have 1 per unit here you have 1.5 per unit as your voltage that is seen on a phase to ground basis. And if you look at your fault current level and if you look at your fault current level. So, your peak fault current level is reduced. So, we see that you can have advantages of the two cases when you are now connecting a impedance to your neutral. Again depending on what is the particular way your application you might have different ways of connecting your grounds and we will continue with this discussion of grounding in the next class. But you can see that this is a important aspect of any system design or even equipment design to ensure that whatever your designing is actually safe and can be used in manner which would not cause any danger to the potential user of the equipment. Thank you.