All right. Good morning, everyone. Welcome to New Day again. Let's begin this time with the word of prayer. Maybe Rupa, is it okay if you can please lead us in prayer? Or Samuel? Okay, Rupa is available. Go ahead. Good morning. We come to your throne of praise this morning with thanksgiving and praise. Thank you for this journey. You're with Father in each class. You have taught us your truth. Father God, we thank and praise you for our faculty. Father God, first of all, and the way He has revealed the truths to us, Lord. We thank and praise you. Master bless this class as we gather at your feet, Lord. Open our hearts. Open our minds. Renew our hearts, Lord. Our minds as we dwell on your truth, Master. It was a time of good understanding and Father grace and power to put them into practice in our life, Lord. Thank you for this light truth. In Jesus' name I pray, amen. Amen. Amen. Thank you so much, Rupa. All right. So this class will be our last class. What we'll do is we are in chapter 21. We'll look at entrepreneurship. Then we'll also look at chapter 22 workplace transformation. But what I want to do is just look at the important points, certain key takeaways, and we'll apply this. Like what we've been doing through all the topics was we have been trying to apply everything that we learn, both for the workplace and translate that for the ministry, right? And so we will try to do that as well. And let's look at chapter 21 entrepreneurship, right? Now deciding to become an entrepreneur is exciting, right? Or even if you look at ministry, if you know that God has called you for ministry and you're deciding, okay, I'm going to start ministry. It's exciting, right? It's a wonderful season. Along with that comes risk, comes responsibility, and the whole thing of the idea that you have or that vision that you have inside to make it come forth or give birth to that vision. That is where we must be very intentional, where we need to really look at God's word. We need to make sure that it is the Lord who is leading us in this direction, right? So let's look at a few points. I'm going to talk about both in the workplace and in the ministry, right? Because both, I would say, even starting a ministry, pioneering a ministry, is like entrepreneurship. Now when you look at things that are happening, there's so much that needs to be done even in ministry before we launch out. So let's look at a few points. Entrepreneurship, the first point, prepare well before the launch, right? I'll read Luke chapter 14, 28 to 30. If one of you is planning to build a tower, you sit down first and figure out what it will cost to see if you have enough money to finish the job. If you don't, you will not be able to finish the tower after laying the foundation and all who see what happened will make fun of you. You began to build, but you can't finish the job, they will say, right? So Jesus is teaching us something very important here. He's saying, when you plan something, any of us, when we plan something, first sit down, figure out what will it cost. Now the word cost doesn't always mean money, right? Money, material, manpower, resources, time, and what does it cost to start something? One of the things that I'm sure many of us here are eventually planning to probably start your own ministry, don't be in a hurry, right? It's a wonderful thing. It's a wonderful thought. It's wonderful that God has put a vision in your heart, whether it's a ministry or even a small business. Don't be in a hurry, sit, write down your plan, figure out the cost. Okay, this is going to take me a year for me to launch out. So before I launch out, what do I need? I need, in terms of finances, I need to be able to provide, I need this much of amount. In terms of material, I need this. In terms of manpower and stuff, I need this many people. So we need to sit down and really count the cost. What is it going to take? Now, when you look at ministry as well, say, for example, some of us are called to pioneer, the wise thing to do is to wait. You can start off small. So when you look at, if you know that, okay, God has called you, plan ahead, right? So you know, okay, I'm going to start a church. So, you know, the most common things you need when you start a church is one, you need your documents. You need to have all your documents, right? Two, you need a, you can even look to start in a house. But eventually you can't have more than 20 people in a house and then music and then, you know, you don't want to disturb the neighbors.  But if you move to a place, right? You need, we need to plan. Okay, if I move to a hall, then I need speakers. I need chairs. I need some kind of instruments. I need the mic system. And so even before we launch out, it's very important to prepare. I'm reminded of this young man who I know, very, very fervent young man of God. And we know each other from Bible college days. And he called me. It's happened maybe two years back. He called me. He said, I'm going to start a church and God has spoken to me. I said, that's wonderful. So how do you plan to do that?   We'll hire a hall and said, that's wonderful. So, so one of the first things that I asked him was now we know that God is our provider, right? Jehovah Jaira, he is our provider. We know that, right? So no way we are saying don't trust in God. But what I told him was even as you trust in God, prepare well, right?  What are the equipments you need? What are the materials you need for that? He said, no, I prepared all of that. But what he did was he left the job. The next month, he left his job and he would stay at home. He would pray 20 days, 30 days fasting and praying, which is wonderful. You know, spiritually, he was growing very strong. God also gave him the idea. But the problem was, I remember he called me and he said, you know, God gave me so many ideas. I have so many ideas, but I don't have anybody to help me execute it. And he said to me, I don't feel like asking people for money. Because initially in the ministry, if I ask people for money, you know, it's not going to sound good. Now that is also right.  In the meanwhile, you also do ministry. And then, you know, you can look to buying the equipment, buying things for the church. But he didn't want to do that. But eventually, you know, somebody had provided and they got a house, sorry, got a hall for lease. But you know, he also told me that they were struggling. They didn't have chairs, so they all were sitting down. And, you know, it was not a well, the flooring was not done. So there was a lot of dust. Children would fall sick. And there were only about 15, 20 people. But then, you know, every time people walk in the dust would rise up. Many of them fell sick and there was no speakers. So he would have to scream at his voice was, you know, affected. And so, after he shared all of this, I always, I thought to myself, it is so important to prepare well before we launch out in anything. This could be ministry. This could be a business. This could even be an idea that God has for us, like a plan. Or it could even be a move from one city to another or from one nation to another nation. Everything needs good preparation. Right. So thorough preparation before launch is very important. Right. To determine to do business or ministry, God's way. Very important. Determine to do business or ministry, God's way as part of preparation. Right. We always want to, we want to see numbers. We want to see growth. We want to see, you know, things growing very fast and whatever we are starting a few decisions that are a few questions that we can ask ourselves is, do I want to launch this ministry of business alone on my own? Or do I want to do it with partners? If I want to do it with partners, who are the co-founders? Or what do you want the vision of the ministry or the work, the business to be? So all these things make it in line with biblical principles. Right. So when we set up something, you know, okay, I am going to follow biblical principles. These are principles that I'm going to do. These are principles that I will follow in my business or in my ministry. Now, many a times when you look at, you know, in ministry, we may end up, you know, in a bid to become successful or in a bid to, you know, become famous or see early success. We may end up taking the wrong routes or measures in ministry and business. Right. Now we must be very careful of it. Don't fall into a trap of early success, babe. Let God take its time. Let God take us through his processes. It's wonderful because your process or preparation is going to be different from mine. Right. If God is preparing me for something ahead, the way he prepares me is going to be different to the way he prepares you. Right. And so we must be willing to determine how God takes us through. But when we know that, you know, we stand on the fact that, okay, whatever I do, I'll do it in a biblical way. I will use biblical principles that is going to bring blessing and success upon our work and our ministry. Right. One of the things that at APC, you know, when we launched out in, when we went to Mangalore, I've said this many a times. We were a couple of people, maybe eight of us, seven, eight of us. And then families and people started coming to church, but then they were coming from other churches. So I had to really make sure that our church is standing on good foundation because it was the initial days. So I would always tell them, right? I would ask them, why are you coming to this place? Why aren't you going to that church? And so they would say, you know, the timing, so they would give other reasons. But I would tell them, go back, tell the pastor, write a letter to them stating the reason why you're coming, why you have left that church and why are you coming here? Give them that letter, thank them and honor them for pouring into your life. You may have been there for a year or even six months. It's all right. They have poured into your life. So, you know, in that way we are standing on good ground. We are following biblical patterns, right? Finally, depend on the spirit of God to empower you in your workplace and in your ministry. Right.  He came up to me and he said, I'm going back to my hometown and I'm going to launch my own ministry.  Depend on the Holy Spirit. First thing, don't be ashamed of small beginnings. You know, sometimes God has given us so much of talents and gifts, right? Maybe we are good at speaking with people. We are good at managing our finances or we are good at, you know, writing or, you know, playing the instruments, worship, leading or preaching, all of these things. When we're good at all this, sometimes it's very easy to put God in the second place. And we may say, okay, God, I know how to do this. I've been leading worship for 10 years now. So we may not, you know, say it with our mouth. We may not say, God, I can manage this. But our attitudes can show that, right? When we don't depend on God, we don't depend on the Holy Spirit. And we say, okay, I can choose my songs, make it sound good, make it sound like they're very powerful songs and it's okay. I can make sure that the worship goes on well. But if I don't depend on the Holy Spirit, it's like saying, it's like me depending on my own skills and abilities, which is not going to last fruit or bring fruit. Because remember what the Bible teaches us. Flesh will give birth to flesh and flesh profits nothing. That which is born of the spirit will give birth to the spirit, right? Very, very important, especially those in ministry. We must not try anything out of the flesh. We must always depend on the Holy Spirit. And I think I've shared this with you, right? When I initially went to Mangalore, I thought, okay, I can do this. I can lead worship. I can, you know, I can go evangelism. I can preach. I can teach. So it was like a one man show, right? And I kept thinking to myself, okay, I can do it. I can do it until the time came when I saw that it was over a year in Mangalore and nothing I could do. I did a lot of things. We did a lot of things, evangelism and spend many hours reaching out to people, but I didn't see the fruit of it. So I would always ask God, God, I struggle so much. Why is it? Why? Nothing's happened. It's been a year. The Lord very clearly ministered to me and I thank God for that, right? That's where the Holy Spirit brings conviction. Clearly ministered to me and said, you are doing this on your own ability. You feel you can lead worship. You feel you can preach the word. You feel you're good in evangelism, which you are. You go, you know, you may have the talents. But even as you have the gifts and talents, surrender that to God and depend on the Holy Spirit. And the moment I did that, I stopped evangelism for some time. I remember we as a church got together and we said, let's do 21 days of fast again prayer and weekly prayers. And then I saw something. Of course, even we also did evangelism reaching out to people, but I saw families coming in. I saw students coming in. What I did for one year, I burnt myself out struggling and struggling and reaching out. But here all I did was depend on the Holy Spirit, wherever I got opportunity, share the word. And God started wonderfully bringing people. And so don't be afraid of small beginnings as well. We looked at this many chapters also previously that small beginnings is how God usually works. Every almost nine out of 10 ministries would have started with two, three, five, 10 people. Nine out of 10 businesses would have just started in their rooms or with their houses, which have gone on to become multi-million dollar businesses. And so I was reading this, you know, whole article about Amazon. Now Jeff Bezos got this idea in the early 1990s and, you know, his own friends were making fun of him. Who is going to go online and order something and it will come to your house? Why is it so complicated? Right? Who's going to do that? And I remember also there's this interview. I think if you get on YouTube, you can see it. The interviewer in the early 1990s, right? The interviewer is asking, what is this company that you have started? You've got about five, six people. What is this company? What's the big deal about what you're doing? And he said, no, now with the access of computers, what we want to do is we want to build up a system where people don't have to go to the supermarkets or the stores, but you can all order online and it can all come home. And the interviewer actually laughed, right? And it was like a mocking laugh. But Jeff Bezos was, he didn't say anything. He just kept quiet because he knew the vision that he had. When you look at him now and look at it, what's happening now. Anyone can order on Amazon, even people in villages are, you know, probably aware of how to order on Amazon and they are reaching out. And we know that he's a multimillion dollar man, but it all started off small, right? As we apply this in the workplace, we can also apply this. Now, I'm not saying Jeff Bezos followed, you know, Godly principles, but what I'm saying, what I was trying to get at was that when we start with small beginnings, don't be ashamed of it. People may ridicule, people may mock. Don't be ashamed. I remember when the people of Israel came to the wall of Jericho and they were just walking around. They were being mocked by the people. What are these people doing? It's all right. If God has put that vision, God has put a plan in your heart. Go ahead with it. Trusting the Lord. Next one, don't be distracted with quick success. In for a long haul. Now, Proverbs 2021, the more easily you get your wealth, the less good it will do you, right? Don't be distracted with quick success. In business, maybe suddenly, you know, if you're starting a business, maybe in a year or so, you may see very good success. Don't be distracted with it. Don't let the quick success of fame or money get into your head or it can take control. Last week, yesterday, we spoke about money and how important it is to handle money the right way. Stay focused on the vision, stay focused on the mission, stick to your values and continue on the same path. When it comes to ministry, you may have started small. All of a sudden, you may see success. You may see from 10 people, your church is suddenly in one year has grown to 100 people. Now, don't let that success get to our heads. Sometimes what the mistake that we can do is we can look at others and say, hey, that church started 10 years back, but I started only two years back and I have 100 people. The church only has 70 people. And so, you know, pride may come in. We may think, oh, you know, we may get distracted with the success that we have tasted at an early age or at an early time in the business or ministry. Don't let it distract you. Remember, especially in ministry, this is not competition, but we have one body. So it's sad to say that in many cities that I've been, I've seen it as a competition. When did you start the church? How many people in the church? How did you do this? And then it becomes a competition. Stay away from it. Don't be distracted with all that. Keep the vision in your heart. Keep the vision in your mind and say, God, this is what I'll do. I'll do the right way. Two, three, don't be hasty for profit. Refuse to take shortcuts to make quick profits. Don't compromise on your values and principles to see success.  And all of a sudden, if we are not careful with ourselves, then we may end up taking up shortcuts to make a quick buck or to make a quick profit. And so we must stay away from that. Keep your hands as clean as possible. That is why, you know, I think next year you will have church administration. And you'll learn about how church needs to be or ministry needs to be functioned, right? It's not just one person doing everything, but you need to have certain things set in place so that, you know, the organization, the ministry does not fall. And as a leader, we must be careful in that. Don't be hasty to make profit. I like this next point. First, plant your fields, then build your barn, Proverbs 24, 27. Now, imagine we build a barn without planting fields. It doesn't make sense because we're going to have an empty barn and then we're going to wait for the harvest to come.  And then when the time comes, when the harvest comes, you know, okay, I can build a barn now. And I can prepare for taking all the crops, everything that has been harvested, I can prepare to put them in the barns. So why is this important? Why is the Bible mentioning this? First, plant your fields, then build your barns. The Bible is teaching us something important here. It's teaching us to stay focused on what is important. What needs to be done first? So here, you're saying, first, plant your fields, then build your barns. Don't do it the opposite way. Don't build the barns and then plant your fields and then say, okay, no, plant your fields. And during the process, I'm just giving an example, right? I'm not sure about the time frames, but just an example. So if you put a seed on the fields, you're looking after it and you're expecting, you know, it's going to take, for example, a year. Now, eight months down the line, you can see how the crops are doing. Okay, and you feel, okay, this year I'm going to get a good harvest. So the barn that I prepare must be this big so that, you know, everything can go into this. So probably about the eighth or the ninth month, you start preparing for the barn. Now, the wrong thing to do is wait till the end. And then when the time of harvest comes, oh, where do I store up my crops or where do I store up the harvest? Now, so see what is important first. Every area needs to be done, but stay focused on what is important and then go to the next step, right? The barn can be built, but first the fields have to be planted, right? Now, even in ministry, in business too, in ministry, there are things that need to be done. And you know, okay, this has to be done, set priorities. And one of the things that we personally do as leaders is we have so many things to, you know, look at. Sometimes it's probably a house visit, praying for people, our own ministry preparation, preparation in teaching or course material. And sometimes we lose track, right? So it's very important as leaders to, you know, now that we have a lot of convenience on Google calendars, you know, or you can also, you know, have a physical calendar on your table and you can mark things that you want to do, or you can have a to-do list. You know, sometimes what you can also do is when you switch on your laptop, Google Calendar will remind you your tasks ahead for the day, for the week, or for the next 15 days. You can set it up that way. So you can set up your priorities and make sure that it's done in the right way. Keep a close eye on what brings in the bread and butter as your business, as the ministry is taking shape. See which areas are profitable. See which areas are working out well. You know, one of the things that we did in ministry in Mangalore, you know, we tried everything. But one of the things that really worked, right, was something called as worship evenings. So what we would do is Friday evening, we would make invites one hour of worship and prayer. Basically, it's more of worship, right? We worship and in between the songs, we spend time in prayer. Now, when we started it, there were a few people who joined, but then we started reaching out to people, students, giving out invites. And then slowly, we saw that people started coming in. At one time, we had a big concert, and we tried that, but we did not see any fruit out of it. So we said, okay, let's stick to what we know best. Let's stick to what is really working out in the city. This is something that's working out and we continue to do that, right? So keep a close eye on your bread and butter, meaning which area of your work, or your business, or your ministry is bringing forth success, right? Now, for example, there are churches where the women's ministry is doing really well. So you can encourage them, or in some places it's the youth ministry.  They are doing really well. So you can target youth and say, tell the youth, okay, let's reach out to other people. In some places, we have families that are very close knit together. They are willing to reach out and invite new people. So whatever it is, keep a close eye on that and try to build on the places that we are, you know, success would be a seeing success and stay clear of the pride that comes with success. Proverb 16, 18, pride goes before destruction, a haughty spirit before a fall, right? As we see success, as we see, you know, success coming in continually, pride is the problem here.  All of a sudden, as the church grows, and you know, maybe you're coming on TV and become famous, songs have become famous, sermons have become famous, pride creeps in. Pride is dangerous, pride is destructive. Pride comes before the fall, right? Pride comes before the fall. Always remember this, this verse is so true. If pride is coming in our hearts, be sure that it's only going to be destructive to our lives. So the moment pride comes in, we are to say, God, help me to walk in humility. Ask the Holy Spirit to humble us and we operate on the principles of God's Word. Always the best way is to say God, acknowledge what God has done. Say, God, it is not me that it is you who has blessed me with this. It is you who has blessed me with the ministry. All the people here, I started off with five, six people. Now we may be 500 or 1000 people, but it's not me. It's not because I can speak, it's not because of my talents and abilities, but Lord, you are building your church. The moment we sit on that foundation, the moment we are strong in that area, pride will not come in. So stay very, very careful. Be very, very clear about certain things, especially in ministry. Stay away from it because pride comes in. Be assured that it's destructive and can be dangerous to the future. So just say, God, whatever I have is from you. The moment we stand on that foundation, the enemy is not going to let pride come in. Next point, your personal income and your benefits, keep it right. For example, as a pioneer, there will be times you would like to enjoy your hard work and the fruit of your hard work, but do not do that excessively, meaning don't indulge too much in lavish spending, especially on your own. Now I want to be careful here. When we start a ministry, and you know, okay, the ministry is growing. I'm just going to use ministry as an example here. You start a ministry and you know the ministry is growing and all of a sudden you have a lot of finance, you have a lot of money coming in. And now when we look around the world, we see this as a problem. It's good. God blesses us with money. We can enjoy the benefits of our hard work. If we need certain things, we can go ahead, buying a car, buying a house, nothing wrong with it. But when you indulge in greed and lavishly use it, which is not going to be profitable to oneself or to the ministry or to the business, then that is not acceptable. Avoid excesses. You don't have to prove people anything. You don't have to prove others, okay, this is what I have. This is my house, this is my car, this is my other car, these are my bikes and these are my assets that I have. You don't have to prove anything. In a day and age, right now, we see a lot of ministers of God who have come very rich and it's very sad to see it. They show off with it or they say, okay, I bought this jet and that jet and they buy a couple of private jets and there's so much that's happening around the world. It's not wrong to buy things for their personal needs. If it's ministry, it's all right. But what I'm trying to get at is God blesses us. We're not to be greedy of it, greedily use it and spending it lavishly on unwanted things. We don't have to prove a point to anybody, right? I like this, the end verse, verse 9. Who is the Lord? Or lest I be poor and steal and profane the name of my God. Remove falsehood and lies far from me. Give me neither poverty nor riches. Feed me with the food allotted to me. So wonderful this is. Don't give me poverty lest I curse God. Don't give me too much of riches lest I forget God. Let me be a person who will be satisfied with what God is giving me. Next point, multiply what you have by empowering others. Again, it's a very important aspect on leadership. Delegate, give responsibilities, train people and then if you know that they're going to do something, they're very good at it. Develop it, grow, multiply.  Now this is, women entrepreneurs are on the rise over the past decade. We've seen plenty of them and it's wonderful. But always remember if it's a married woman who's starting a business or a ministry or as an entrepreneur, she must make sure that she has these three aspects of a virtuous wife, a mother and a homemaker. She cannot put these three aside and say, hey, I'm an entrepreneur. I'm reading this article by a very famous businesswoman. She went through a lot of hardships as a young married woman. She pursued the whole thing of wanting to start her own business and she had three children and they were all tiny children. But she went through a very difficult time. She would try to look after the kids and also look after business. But with the wisdom of God, she was able to look after her children in the right way and also her business began to flourish. And one of the things that, I forget her name, sorry, one of the things in that article that she said was, in a bid to gain success or gain profit, earn money, I made sure that I was there for my children so that when I grow old, they will know the importance of family. And she very clearly says that her children as well work in such a way they're all, now the business is a big business, gone global, but she still says, if I have to go back and be a wife, a mother and a homemaker, I will still do it because she didn't regret any of those times. And her children also have grown up so beautifully with this whole understanding of money is not everything. Relationships are greater than all of that. So this is the whole topic on entrepreneurship. Let's just quickly, we have 10 minutes. Let's quickly get into workplace transformation. Before that, any questions on entrepreneurship or what we just looked at chapter 21? Any thoughts, any questions?  Is there anyone here? Is that, okay, Samuel. Yes. Right. Anybody else? Yes. Samuel, is that your own ministry you're planning to start? Yes. Both an organization as well as a ministry. Yeah. Thank you. Yeah, that's wonderful. Thanks, Samuel. Thank you for sharing. Anybody else? Okay. Louis says you're going to start his own ministry. Wonderful. Wonderful. Okay. Provocative spring. Take your time. Pray. Don't be in a hurry. Hear from the Lord. I need then start very good. Anybody else? Your plan to start your own ministry, your own business. If the Lord has put it in your heart, sometimes you may feel God, I'm not qualified enough or I'm not a good speaker. I love what God tells Jeremiah. He says, Jeremiah, don't give excuses saying you're too young or you don't know how to speak. I'm going to go with you. Same thing he said to Moses. Give me that excuse that you don't know how to speak. I'm going to go with you. And so be assured that God has put something in your heart. Pray about it and go forth boldly. In the book of Revelations, the Lord Jesus is talking to the church in Philadelphia and he says, I've opened a door ahead of you. Go and enter into it boldly. So be assured that God is with us no matter how big or how small that vision is. God is with us. He's going to help us. Right. So that's wonderful. Let's get into chapter 22 quickly, workplace transformation. Initiate a culture shift. Now, in the workplace, it's very important to bring transformation, bring changes. Right. Now, the Lord Jesus commissioned his followers to be salt and light. And he gave them the reason to do that. He said, okay, if the salt is of the light, if you're the light, you're going to be on top and people are going to watch you. You're going to be a light to the people around. And if you're salt, you're bringing flavor to their lives. But if the salt loses its saltiness, it's of no use to be then to be trampled. So all of a sudden Jesus is initiating a culture shift.  He wants us to be a light. He wants us to be the salt. And so Jesus was trying to influence his disciples and he did it in such a beautiful way. Right. He didn't say, look what I'm doing and look at you. Why are you all like this? No. He brought it forth through words of wisdom. Right. And so we can do that as leaders. Bring forth transformation through the scriptures. Now we have the entire scripture with us. So bring forth changes, bring forth culture shift within the organization or within the ministry as well. Right. Create constructive changes. Right. Small changes can make big differences. Right. But those small constructive changes can influence an entire sector of your ministry or your business. Right. So apply these principles that we have learned all through this entire course. We can apply principles and see constructive changes in our workplace, in our ministries. Right. And we looked at workplace relationships. We looked at the topic on vision, mission, values and cultures. And we looked at how important it is to have that second place, whether it's a business or ministry. Right. So you apply that. Third point, be a transformational leader. Now there are two kinds of shepherds. One, the good shepherd who puts himself ahead of the sheep, which means the Lord Jesus says, I am the good shepherd. He gave his life. And then there's the hired shepherd. Right. A shepherd, if he's looking after his own sheep, he'll give his 100%. David says it wonderfully. He says, you know, when I was looking after my sheep, if there was a bear or a lion, he's telling Saul, I have killed it with my own hands. Now David was a young boy. And if you see a lion or a bear, it's not a simple thing, but he went and killed it. Why? Because it was his. Imagine David had to look after somebody or imagine any other shepherd who had to look after somebody else's sheep. And when he sees a lion or a bear, he's going to run for his life. Right. So there are two kinds of shepherds, the good shepherd and the hired shepherd. And instead of taking care, the hired shepherd, instead of taking care of the sheep, he's going to, you know, abandon and run away. Now a great leader or a good leader will always be there for his people. Right. Good leaders care and serve the people that they lead. Right. The transformational leader will set out to transform. He seeks to transform the lives of the employees. He seeks to transform the lives of the customers also people who are being served in the organization. So one of the questions that, you know, we can ask ourselves is what kind of a leader are we? Are we like the good shepherd or are we the hired shepherd? When troubles come, do we run away or do we stand with our team and say, okay, let's fight this together? Or do we run away and say, okay, their problem, their headache, let them manage with it? No. God is calling us to be good leaders who can bring transformational change in people's lives. That's the last point. I demonstrate the kingdom in the workplace at 17, 16 to 17. Now, while Paul wasn't waiting, waited for them at Athens, his spirit was provoked within him when he saw the city was given over to idols. Therefore, he reasoned in the synagogue with the Jews and with the Gentile worshipers and in the marketplace daily with those who happened to be there. So wonderful, right? Paul went to the marketplace and he began to bring the gospel to them. God is involved in the workplace.  You may feel that, okay, this is what life is, but no. God is interested. God loves to get involved in the workplace. Our knowledge, our science, our technology, our intellectual promises we have gained all of this in the workplace may not satisfy. But when we, when we look at God, we say, God, it is through you. It is by you and it's from you that we have all of this. God can minister to us at the workplace, not just on Sunday church services, but we need to be people who can demonstrate the kingdom of God wherever we are in the workplace, in colleges, in schools, and not only on Sundays. And here's the best part. Even as God has called us to serve, He, we serve through the gifts of the Holy Spirit that He has given us and empowered us with. Amen. Amen. So I had a wonderful time teaching this entire course and I personally have learned a lot of things. I hope that each one of us have taken up and, you know, the Lord, the Holy Spirit has really empowered us, you know, has given us insights from this lesson, from this course. And thank you so much for joining along. I know it's a lot of material, but I tried my best to, you know, bring in even the ministry aspect to it. And so to bring this section to a close. We will not have classes from next week onwards, but I will post the final assessments by today, the end of day, and this will be an open book exam. I put the due date too. So just take some time, fill in your answer sheets and post them. I'll put the guidelines in as well. All right. Let's close in prayer. Yes. Anyone, anyone can please close in prayer. Abraham. Can you close? Yes, Pastor. Precious Father, we thank you for bringing us to this conclusion. Father, we are grateful for all that we have learned. And we pray and ask for the grace and the wisdom that we will not be Sunday Christians, but will be Christians all the time in our workplaces. Father, we can be examples at our workplaces and also to impart the world as you have given us. Father, we thank you for our pastor. We thank you for the opportunity of giving him to release what he knows to us. Father, we pray that we'll be good stewards of everything that we've learned that we'll be able to pass it on to other people. Father, we thank you in the name of Jesus we are praying. Amen. Amen. Amen. Thank you everyone for journeying along with this. May the Lord bless you. See you next year as well. Next semester. Have a great time ahead. God bless. God bless. Bye bye. Thank you so much, Pastor. God bless you too. Thank you, Pastor. Thank you. God bless.


Welcome to this deeper dive into named entity recognition. Since named entity recognition is a text mining task, I strongly recommend that you go watch my short introduction to the core concepts of biomedical text mining first if you've not already done so. The goal of named entity recognition is to find things in papers. In other words, go through text and mark it up. It consists of two subtasks, recognition, which is to see that a name is for example a name of a gene or protein, and normalization, also known as grounding, which is to say which gene or protein it is. Since normalization is needed for most actual use cases, the two are often considered one big task and just jointly referred to as named entity recognition. Today I'll cover how you build the all-important dictionary, how you can use a dictionary for doing named entity recognition, how you can improve the results further by using machine learning, and finally what you can use named entity recognition for. The dictionary is essential because it defines your universe of entities that you're looking for. For each entity, it provides a unique identifier, as well as the multiple different names under which it may be referred to. This means that a dictionary of gene names would tell you that there's something called CycleDepend and KineH1, and that CDK1 and CDC2 are the same thing. It will also tell you that there is an organism called Saccharomyces cerevisia, and that this is also referred to as budding yeast. You want to map all these names to interoperable identifiers, and for that reason you will typically want to start either from an existing database such as Uniprot or NCBI Taxonomy, or from an existing ontology such as genontology or disease ontology. Even though these resources come with a lot of synonyms, you will want to add additional synonyms from other sources if you can, and even then you have to deal with the fact that your dictionary will never be completely comprehensive. For this reason we use name expansion to create additional names automatically. That handles things like prefixes and suffixes, for example if you have a human gene name, authors may put an H in front of it to point out that it is indeed the human gene and not the mouse ortholog. We want to handle abbreviated forms, so when NCBI Taxonomy tells you that there is a species called Saccharomyces cerevisia, you want to still recognize it when it is written as cerevisia. Similarly you want to handle plural forms, so when genontology tells you that there is something called a mitochondrion, you want to generate the plural form mitochondria to also identify that in text. Once you have built a good dictionary, you can use it for doing name density recognition. For that you need an algorithm to do flexible matching of names against text. This could be for example case insensitive so that when you have a name CDK1, you can still match it when it is written with different casing of the letters. You may also want to handle spaces and plafons so that when you have the name CDK1 written like this in your dictionary, you can still find it in text when it is written with a hyphen instead of the space. All of this functionality is implemented in the tagger software developed in my lab, which is open source so you are welcome to go use it. It uses a custom hash table between the scenes to be very fast. It can handle more than 1000 abstracts per second using just a single CPU core and on top of that it is highly parallelized. Also this approach is universal. You can build any dictionary for any kind of entities and use it on any text. If you do a good job making your dictionary, you can generally get to something in the order of 70-80% recall. That means your method can find 70-80% of what is mentioned in the text. However, initially you will have terrible precision. That is, it will make a lot of false positives. However, this is fairly easy to fix because usually a few bad names, such as the human gene named bad, are responsible for most of the errors. And that means that if we just manually identify those errors and create a curated blacklist of bad names that we don't want to use, we can get rid of most of the errors and suddenly we have a precision of 80 or even 90%. That means that 80-90% of what we find in text is correct. If we want to get even better, we can complement this with machine learning. Machine learning can either look at the shape of the names, such as is it 3 uppercase letters followed by a digit, in which case it's likely a gene identifier? Is it 3 uppercase letters that could be a gene name, but it could also be an acronym for something entirely different? Or is it 3 lowercase letters, in which case it's likely a common English name? You can also look at the context around the names. In other words, the other words around them. So if you have a gene name like SDS and the text says hepatic SDS expression, you would think that this is clearly a gene name in this context. However, if the exact same name appeared and it said trisk lysine SDS buffer, you would know that this is for sure not a gene name. To learn this, you need an annotated corpus that you then use to train an entity type classifier, a classifier that looks at the words around the name and predicts is this likely to be a gene name, is this likely to be a disease name, or is it likely to be something completely different? Most approaches nowadays use deep learning for this. They start from a pre-trained language model such as BioBird and then mask the names and train a classifier for the specific task. The downside is that you need an annotated corpus and making this is very labor intensive. Also, these models can do recognition only. They cannot do normalization. So they can only look at the context and say the hidden name in the middle is likely to be a gene. They cannot say which gene. And finally, deep learning is much slower than dictionary-based name-density recognition. For this reason, it's often used to filter dictionary-based name-density recognition results instead. That way you can improve the already good precision. And you have the further advantage that normalization has already been done thanks to the dictionary-based name-density recognition, so that problem is gone. And last but not least, it allows you to process much less text because you only need to look at the text around names that were already found in the dictionary, as opposed to having to process all text in your corpus through the deep learning model. What can we use name-density recognition for? One is curation support. If you're a curator making, for example, the Uniprot database, it can be useful to use a tool like Extract, which produced this web page where the names are marked up, where you can then click on the names and get pop-ups with useful information about the entities, including the database identifiers, which can make annotation faster. You can use it to improve information retrieval. The way that works is that you get synonyms information and ontology structure, so that if you search, for example, for psychiatric diseases, you will also find papers about mental disorders and papers about specific mental disorders like major depressive disorder. Finally, and certainly not least, you can use name-density recognition for relation extraction, and that is in fact a prerequisite for doing relation extraction. That is what I will cover in the next presentation. Thanks for your attention, and I hope that you will watch this one.


And now I have to announce our speaker for the session. Everyone likes to tinker with electronics, I think at least everyone who is here in the room. And it becomes harder and harder because a few years ago you did soldering of through the whole components and everything was easy and things got smaller and smaller and now you need a microscope and strange and extremely costly equipment to build things and it's hard for a hacker front to keep up, we have to keep pushing the limits and our speaker Hunz will tell you how to keep pushing the limits. So please give a warm welcome to Hunz. Well, hello everyone. So let's push the limits together and we also need to push the tempo a bit because it's quite a lot of content and that's why I might skip some details but you can read them later on the slides once you need them. So more sophisticated with yourself electronics, why do we need this or why do we want this? Whether professional electronics obviously get more and more sophisticated and we need to keep up. You can do really great stuff nowadays even with do it yourself. For example, you can build high speed FPGA boards with more than one gigabytes per second RAM throughput. You can use those as software defined radios and logic analyzers you can build on your own. You can build custom networking equipment for example, ARM based routers with gigabit ethernet interfaces and so on. Now what are the challenges for do it yourself projects? Well, one point of course is that the ICs we nowadays have get more advanced and mostly they don't have leads anymore. So if you look at your batch, there's the ARM controller on this and it doesn't have leads. You cannot solder it with a soldering iron any longer. This is a ball grid array package.  And this is done because it saves precious PCB space. You need those PCB space in the cell phones of course and in other devices as well. So you can pack more IOs per space. Now it's similar for QFN packages. These are very small and you cannot easily use a soldering iron for those. So this of course is a challenge the chips themselves. Then there's bots with four or more layers. We need those due to the high number of signals. Otherwise we cannot access all the signals that we need. We need other soldering techniques and this often means reflow soldering. We need also high mechanical precision for the assembly because the mechanical tolerances are quite narrow and we have to work very precisely. We also have faster buses and interfaces. For example DDR buses and PCI Express for example, HDMI and so on. These are fast signals and the layout is much more demanding for those of course. The professionals have expensive software for this and we also need better software or more time to compensate for this. And we also need more know-how or you would need more know-how if you don't have expensive software. In this talk I'll give some general hints first. Then we'll have a look at soldering options with solder paste and how to assemble a board. We'll have a look at high speed buses and interfaces. Then we'll have a look at mighty layer boards. First we need to understand a bit why we, what are important things we need when designing a multi-layer board. And afterwards we'll have a brief look at design software. Most of you probably already using EGLE. So some general hints first. It's generally a good idea to make a tiny test boards for risky parts of your design. For example, if you want to try your first DDR memory, it's not wise to build a real complex board around this if you don't know if this will work. So make a tiny design, just test the complex part first. And you might want to patch some signals later so this means outer layers are better of course than you can, you should use electrolys nickel gold finish for the boards because you really need this for fine pitch and BGAs because the other option is hell hot air leveling. This is basically solder that is shoved across the board with hot air and this is a rather uneven surface and this is bad for BGAs and fine pitch of course because some balls might still hang in the air then. We need a higher soldering temperature for PB3. Usually it's 237 degrees Celsius and the maximum temperature for most of the chips is 260 degrees. So we have a rather narrow margin there and yeah. Then another thing is some people do the BGAs just with flux and without soldering paste. I tried this a few times and it worked four times but it didn't work for one board. So I'm no longer using that. I'm using solder paste for BGAs now. It's still possible to fix those boards with hot air but I think with paste it's better. Then the popcorn effect is something you need to consider. The thing is humidity from the room will get into the chips if you leave them in the open and once you heat those chips the water will boil and vapor will be created and it will blow your package like popcorn and that's why you get expensive or complex chips like BGAs and sealed pouches. There's desiccant and indicator paper in there and you can reseal those pouches with adhesive tape after you put the chips back in and the desiccant and usually this is fine and you can see if it's not fine by looking at the indicator paper then you have to bake the chips. Here's a simple test board I created just for DDR2 RAM and an FPGA here you can see the DDR2 RAM and the FPGA. I also added an HDMI connector which I connected to the FPGA. Apart from that, there's Tatek chip, some GPIOs and voltage regulators, more wires than necessary. But yeah, I tested it and it did work with 800 MHz although the FPGA was only rated for 600. So yeah, this was a success and I continued. For the soldering you have basically three options. The first option is using a reflow oven. A lot of people are using modified pizza ovens there but you need more heat and temperature control for this because the pizza ovens don't have sufficient heating power by themselves. Then you can order cheap reflow ovens from China. We'll have a look at that but you need to modify those ovens because they are cheap. And a problem with reflow soldering is that you have black surfaces on the ICs usually and also on the connectors and they absorb more infrared radiation from the quartz lamps and why the metal surfaces mostly reflect this heat. And because of this, the temperature on the PCB varies with the location and it gets reflected at those points where we actually need them and the chips heat up more. That's not good but yeah, we have to deal with that. Hot air gun with a hot plate is also an option. There are cheap hot air guns available and the problem is you do not know if the boils underneath the BGA already melted. And with larger copper areas it's also difficult to get sufficient heat in just from the air so you need a preheater. And for preheating you can simply use a hot plate, a normal cooking plate and set them to 100, 220, 150 might also be okay. Degree Celsius, just check it all the time with an infrared thermometer on the PCB surface and you can also solder this way. Waper phase is a really great thing but you need a special liquid which boils at exactly the soldering temperature. It's a really good heat transfer because the PCB rests in the vapor phase and is not immersed in the liquid. So overheating the ICs is very difficult but if it really does get too hot very bad things will happen because hydrofluoric acid will be produced and you don't want that in your house. So you should look this up if you really want to go this way. There are DIY projects. The liquid is very expensive but you have to buy a liter or so in the beginning or half a liter but this will be sufficient for quite a lot of runs. You also should use a high pot so the vapor doesn't get out of it. So when we use the reflow oven a real reflow oven, the cheapest one usually is the T962 from China. It has a very small holding capacity. It's about one Euro board or so but it has very high heating power compared to the place and this is often a problem with the pizza ovens. There's an arm 7 controller in it which isn't read protected so you can simply dump the firmware. I did this and I reverse engineered it because it made the boards too hot and yeah, I did a test run first and this board was completely unusable afterwards. So I wrote my own firmware and the temperature controller is implemented on a PC. It's just connected to the oven using a 3.3 volts RS232 and there are just a few comments for heating and running the fan and reading the temperature. The host code is Daniel Lua. This is rather easy to adapt and you can also easily add new temperature profiles. It's a tiny firmware. You can run it completely from the RAM so you do not have to erase the original firmware and yeah, I put the code online so you can have a look at it. The problem is the documentation is missing right now. Yeah, but I'll try to add it later if you need it before you can simply ask me. So when using the T962 oven you should replace the masking tapes that's used in it with capton tape because the masking tape isn't heat resistant and it will smell a lot. Then for my alternative firmware you need pin headers for RXN2X obviously, ATX obviously. You need external reset and boot buttons so you can access the boot loader and you should also add pull-up resistors for the triacs because those triacs turn on the fan and the heating and those will be on while you're in the boot loader if you don't add those pull-ups. Then I'm using screw nuts as spacers for the PCB so the PCB rests on those spacers and it gets a bit better temperature profile there because at the bottom there's not sufficient heat here. I also measure the temperature directly on the PCB. You can see the sensor here. This is a K-type sensor and it's placed here directly on the PCB and those K-type sensors, they are very well suited for high temperatures and you should do some test runs first because it won't work out of the box. You need some time and patience. There's more projects regarding this and there's also some documentation. Some is in German, there's probably English one on the net as well. So I already, did you show you this photo? Here you can see the cable coming out of the oven with a serial USB cable attached. Here's the board resting on the screw nuts and this is an interesting thing. These are the waves that you use for the reflow profile. This is actually a wave for Xilinx FPGAs and unfortunately the description is in German so the red one is the temperature that we want. The green one is the temperature of the PCB and the blue one is the air temperature. So you can see that the air temperature first is a lot higher or a bit higher than the PCB and at about 160 degrees that changes. The air temperature actually then is quite a bit lower than the PCB temperature and that's why we want to measure the PCB temperature. The oven by itself just measures the air temperature with two sensors so you can simply rewire one and put it on the PCB. For those reflow ovens you want to use solder paste. The solder paste you put on the pads of the SMD parts. A solder paste under the microscope looks like this and there are tiny solder balls embedded in flux and you also need a stencil for fine pitch FPGAs. A stencil is basically a stainless steel mask with openings in it and you force the solder paste through those openings and it gets on the pads and it stays there. Then some board houses offer free stencils for your boards and others don't and sometimes it's cheaper to just order a dummy single layer board with a free stencil than ordering expensive stencil from another board house. This is what it looks like when dealing with soldering paste so here you can see the stencil. It's placed here above a PCB which I already had beneath it. Here's some masking tape I used to fix those things. Here is the soldering paste and here you can see some fixing parts. For fixing the board it must be really tight and those fixing parts you can order from the web or you can make them yourselves. I just ordered them from Better Layout. Those are the PCB pool people. It's not very expensive and the good thing about this is that it's made from normal PCBs so the height of this already matches your PCB then and you can simply align it then.  You need to fix this stuff really firmly so you don't move the stencil around while printing and the fixing kits already mentioned that. You need to stir the paste really good and before using it and you should keep it in the refrigerator it will be good for about one year. If a tiny paste droplet covers two adjacent pads this is not always a problem. Sometimes you can just ignore this and you need some sort of feeling for this. It's a bit hard to describe. But usually if it's just a tiny amount it's not a problem because it will flow to where it's needed and where it should be. Cleaning this stencil is a lot more difficult than one might imagine because the solder paste is quite sticky and I tried ethanol and isopropanol but the best thing I found with household chemicals is lighter fluid and there are some special cleaning fluids available as well but lighter fluid really works very well. You can also use this to clean the PCB if you messed up the print somehow and you can then start over. You can also clean the components usually. You should wear a lab coat because this rather messy paste and we'll get everywhere and getting this out of your clothes again is quite a challenge. When you place and align the parts this is often a challenge as well. You should start by placing the most challenging parts. These are obviously BGAs and QFMs and do the easy parts later. This way if you mess up with the challenging parts you cannot easily fix this and you need to remove everything and clean it and start over again. So that's why you wanna do the most challenging parts first because then you can start over with a minimal time overhead. When designing your board you should place a rectangle around the chip in the silk screen of the board for BGAs and QFMs because that way the initial alignment is much more easy. And yeah well then you can use a tweezer for picking and placing the chips. Vacuum tweezers, you should only use those with electric pumps because the other ones will lose their vacuum in about 10 seconds and the chip will drop somewhere. Then gently place the chip on the solder paste and then you can still align it a bit. After aligning it carefully inspect it. I usually use an off the shelf magnifying glass and inspect it from different sides and different angles so that it really matches the alignment in the silk screen very well. With QFMs you can also have a look at the pads from the outside. And once you're satisfied with this you should push it slightly down because that way if you move the board around it'll stay in place. I did a tiny placement helper for Eagle. This is hacked together. Yeah and it's done in Lua, it needs Lua XML and LGI is Lua G-Object Introspection so it's a wrapper for all the G-Lip and G-Objects and GTK. And that makes it quite different to use on Windows. I don't think anyone has now to this day successfully used LGI on Windows. I don't know about with X. The code you can get here. The usage is rather simple. You just invoke it with the board as an argument. It's easy to use once you manage to install the required things and it basically translates the Eagle XML calls to Kyro calls. It requires quite some RAM because it uses one Kyro surface in RGB 32 bit per layer because Kyro doesn't offer indexed palettes as far as I've seen. But, well, what's nowadays hardware is doable. It looks like this. Here you can see the board and here you can see the elements. You can switch to the layers tab and turn off layers, individual layers and there are shortcuts for top and bottom and so on. You can scroll around here and switch to the values. It also shows the values down here and it highlights all the places where this component should be placed. You can also mirror along the X or epsilon axis because it's useful if you turn the board around and wanna place the bottom side. Okay, then high-speed buses and interfaces. The next challenge, we need a good signal integrity for high-speed signals and this is a challenge because of two things. The first thing is we need length matching so if you have several signals that should arrive at more or less the same time at the receiver, you need to do length matching. That means the tracks on the PCB need to be about the same length so that the signals arrive at more or less the same time. Here an interesting thing is that the propagation speed or the propagation delay depends on the dielectric constant, the epsilon R of the insulator. This is basically the FR4 on board and here's a rule of thumb that it takes about six picoseconds for a signal to travel one millimeter on top or bottom or seven picoseconds per millimeter on the inner layers. So the signals in the inner layers are approximately 20% slower than on top and bottom and this is something you need to consider when doing the length matching. Eagle does not respect that and it doesn't consider wires either so wires are usually 1.6 millimeters and if you use the length matching tool in Eagle it doesn't add to the length of wires. Another thing is usually you wanna place the termination resistors after the last receiver and with Eagle you cannot measure the track length between two chips, you can just see the complete track length. But what you need actually is the distance from the center to the receiver. So if the lines continue to the termination resistors you don't wanna measure this. Another thing is that you need characteristic impedance for the transmission lines and for this you need special multi-layer stack ups and you need to design the width of those PCB tracks depending on your multi-layer stack up. There's a length matching tool for Eagle which I did, it looks like this. You can basically give it to the names of two ICs or two connectors or something like that and one parameter and it gives you the time those signals need between those two elements. It's also Lua and it needs Lua XML but it doesn't have a graphical user interface so it should be fine on Windows too. It's work in progress and again there's no documentation yet there's a conflict file you need to edit, you have to place the propagation delay and speed there and such things. And then you simply invoke the script with Interactive Lua interpreter and then you can call the functions. The first function you need is loading the board, the Eagle board and the second function is this get signal delays, you can either use this without the time parameter then it will adjust the metric distance between the signals by this 20% factor as needed. And this is good if the spec, so the spec usually says you have to do the length matching for 1.5 millimeters let's say. That way you can use this to check the length matching but usually the better thing is to just do the time delay and this you can do with the time parameter. This BGA workshop is called BGA workshop for a reason because there is a lot of other stuff in there. For example, some BGA fan out helping functions and so on, there's really a lot of functions which I have not documented and yeah, you can try to understand them. It's would be too much for this right here but you can also ask me of course. So when we talk about the characteristic impedance, the high speed signals traveled through a conductor like a wave they get reflected if the end isn't properly terminated and the reflected signal adds to the next signal basically and yeah, this messes things completely up. So you need to calculate the geometry of the transmission line to match this characteristic impedance that's needed and you need proper termination then and you might remember this from 10 base two where you have those 50 ohms termination resistors at the ends of the quartz cables. Yeah, when we deal with transmission lines we have to consider a few more details. One point is the termination, I mentioned that briefly and the other thing is the slew rate. You can simulate transmission lines and you can design transmission lines for a given impedance. We also need to consider multi-layer stackups for the transmission lines. We'll see about this later. Termination schemes for the transmission lines are mostly on di-termination for point-to-point connections like LVDS, termination may be needed if you have a multi-point connector. So one transmitter and several receivers, steps you should avoid because you'll get reflections at the ends of the steps and termination should always be placed after the last IC. There's bit in termination that's called on-dite termination in DDR2 and DDR3. So this makes things a bit easier but they're only there for the data buses because the data buses are just point-to-point and clock and address lines, also the control lines, they are point-to-multipoint. So those need extra termination usually but sometimes you can get around this by reducing the clock frequency. This way the signals won't get any better but they have more time to settle before the clock edge comes in. It's a bit hard to, yeah. Here you can see this. Here we have the, here we have this signal, it's a bit, yeah, it's not perfectly rectangular. So if we pull it in the length, we have more time for the signal to settle before the next edge. But usually you cannot simply reduce the frequency of a transmission to improve the signal quality. So the signal quality doesn't change. You can only change the errors that might be produced. The thing is reducing the frequency doesn't reduce the slew rate. And the slew rate is actually the time for the signal to go high or to go low again. And these parts always have higher frequency portions than your base frequency of a transmission. You can see the spectrum of a square wave on the web. And the thing is we need short or fast slew rates for high frequencies because otherwise the signal doesn't reach high or low state in time again. There are some more details on the web. You can look them up. The slew rate you can get from the data sheets and for professional tools there are also IBIS files. These are text files. They also contain waveform data for those signals coming out of the output buffer of this chip while driving a certain transmission line. You can read them with a text editor. You can pass them with your scripts and they can be used to simulate and analyze signal integrity with a given transmission line and a given termination. You can read those easily and you can use scripts to extract the waveform data and plot it in Knooplot for example. Then you can simulate transmission lines with Spice. Spice is an electronic simulation engine but it doesn't come with a user interface. There is a free as in VR user interface from linear technologies. It's called a T-Spice. You can download it here even without registration. There are Windows and there were six versions available. The Windows version you can also use with wine and you can find tutorials for this on the web. There are two open source projects for using IBIS data together with Spice. Those are here. I haven't tried them yet. I just mentioned them here because you might wanna give them a try. You can simulate transmission lines in LT-Spice. First you need a pulse voltage source. It has rise time and a fall time or you can use a time value text file for this source and this PWL file you could generate from an IBIS file. So here you can see this is how LT-Spice looks like. You have, here you have your schematics and here we have the voltage source. It's connected to ground here and here it's connected to the transmission line. Then we have a virtual oscilloscope and we can click anywhere here and inspect this in the graph here. So green shows the signal coming out of the voltage source and pink here shows the signal at the end of the transmission line here. The transmission line is called T-Line in LT-Spice. You can add those here with an add component symbol. You need to set two parameters for a transmission line. One is the electrical length. It's called TD and it's usually sufficient to simulate the longest line of a bus because this will be the worst case. You also have to add the characteristic impedance that sets C0 and those are, you can see here. So we have 120 picoseconds for this transmission line and it's 50 ohms and here we can see the parameters for the voltage source. 200 picoseconds rise and 200 picoseconds fall time, 1.8 volts and so on. You also need to add the input buffer and termination if there's any. The capacitance of the input buffer is important. You need to look this up in the data sheet. Here we can see the capacitance for the input buffer of an actual DDR2 RAM and this is also a very interesting thing. If you increase this capacitance, the signal gets worse very fast. So when you wanna measure this line with your oscilloscope, you will add some capacitance here and you will mess your signal up completely unless you have a good high frequency probe. But I won't cover measuring those things here because this is too difficult to do it yourself usually and it's too costly. Then if you have on die termination, you can also add this resistor here or if you have parallel termination, this is basically the termination resistor. If you don't have any termination, it's usually one mega ohm. In AT-SPICE, you need to use the MAC for MIGA. If you write simply an M, it'll be milli. Yeah, so this happens if you have no termination on this line and it looks quite obscure and this is because it travels back and forth and again and it adds to the new signal and yeah. And this is with a slight mismatch. So we have 75 ohms transmission line and 50 ohms termination and yeah. This is with 100 ohms. So the characteristic impedance doesn't need to be spot on. The signal actually gets worse as the mismatch grows. The specifications often allow plus minus 20% for the impedance, but of course we try to hit the impedance as good as possible. When designing transmission lines, we need to consider this. And transmission line, you always need a lower impedance reference plane that could be either ground or the voltage sublight. Ground is usually better because it has less noise. You can see three transmission lines. This is the first one is a strip line. It's for inner layers. The second one is the micro strip for outer layers and the last one is a co-planar waveguide that can be used for analog signals, but it's not good for buses because it takes up quite some space because you need additional reference things here. Well, this is actually a ground-backed co-planar waveguide. Micro strips, you have a coated micro strip if you add solder mask above it. And for strip lines, there's the option to do an asymmetric or offset strip line if these two heights aren't the same. Now the characteristic impedance depends mostly on the width of the conductor. So by increasing the width of the conductor, you lower the characteristic impedance. The next thing is the height above the reference plane. By decreasing the height, you can also lower the characteristic impedance, but this depends on your multi-layer stackup. There's a dielectric constant of the insulator which affects the characteristic impedance but it doesn't have such a high influence. So the epsilon R is usually 4.2. I'll come back to this later. Differential transmission lines are edge coupled, so there's capacitive coupling between those lines and they are often used for Ethernet, PCI Express, T-Lilata, and so on. They are more robust to noise and they are driven with inverse polarity and that's why they are more robust to noise. The receiver only utilizes the difference between the positive and the negative conductor and noise usually couples into both lines more or less with the same amount so the difference doesn't change. And you need a differential impedance then and this is usually two times the single-ended impedance. There are more details here, you can read this. And for the differential impedance depends on the impedance of the individual lines of the single-ended impedance and by lowering the single impedance you also lower the differential impedance. The distance between those conductors if you reduce it you'll get a lower differential impedance as well usually you have 100 ohms differential impedance. The trapezoid shape you see here is due to edge back during the production. The edge back is usually equal to the copper height so if you have 35 micrometers the upper width is 35 micrometers less than the lower width. This affects differential pairs more than single-ended pairs because it affects the coupling here. The epsilon R for FF4 boards is frequency dependent usually 4.2 is a good value and the effect of a slide mismatch here isn't very high. The next thing is that microstrips here mix of solder mask and FF4 epsilon R. You can see this here, there's the solder mask and also there's the air above this. And here are some example values for the solder mask coating so you have 42 micrometers for example above the PCB and less above the conductors. You can calculate the width, the height and the characteristic impedance. There are approximation equations for this, JavaScripts, you can Google them and see where all you can use. KeyCAD has a built-in calculator for that, you can simply use this one. But if you want to be more precise there are field solvers. There's an open source 2D solver and this solver actually takes such pictures. These pictures are input for the solver and it takes Windows bitmap files, it doesn't have a graphical user interface, it's just a console tool and it takes a wide depending on the size of the image. There's also MDTLC, this is free as in beer. A Windows graphical user interface with a built-in ATLC backend. It uses an older ATLC version though but it's rather easy to use and it also works in wine. ATLC, I already did show you the pictures, it can calculate the signal propagation speed, the signal end and the differential impedance. It has some console tools for generating those bitmaps and you can of course create your own graphics using GT graphics for example. That's what I did, I'll show this. And you need the red for P and blue for N conductor and green for reference conductors. You can use other colors then for insulators and so on. You just need to read the documentation. The only thing here is the ratio between the height and the width and so on, the actual scale doesn't matter as long as it's fine grained enough. For example, one pixel for five micrometers is a good thing.  My tools are still working in progress and I want to rewrite them because I'm no longer happy with how I added new stuff without restructuring them. There's lower code again but no documentation yet and it's in the same repository. There's a config file where some multi-layer stackup definitions are in there and the required impendences at the end of this file. You need to edit these and you can run it again in an interactive session and it will print out the results using the approximation questions, the equations. It will also generate a visualization of the stackup and then you can use this function to invoke ATLC to generate and BMPs and run ATLC. It will take a bit more time but then it's for the fine grained tuning. It needs LuaGD for the graphics and it also needs convert for image magic because LuaGD doesn't produce the right data format. The unitary millimeters and the layer ID you need to set this to the signal layer corresponding to the configuration file and for example here we wanna do a project we name PCI Express and we'll use layer two and we'll try width 0.25 and spacing 0.25. So here this S again is the spacing for differential lines. With multi-layer stackups is the next thing. There's the height between the layers and this depends on the multi-layer stackup. We need to choose a multi-layer stackup which gives us good heights and the custom stackups are too expensive. We cannot use those in do-it-yourself projects and this means we need to choose our PCB house which has a suitable pool process and pool process means they use projects from many different customers and yeah. You need to ensure that your PCB manufacturer won't use another stackup for your pool order. So talk to your PCB house before your design and before production and for controlled impedance you don't need this as well. Now there's a thing called controlled impedance. You can order this and then it will show you really huge prices. Don't use that. It's for project other manufacturer guarantees a certain characteristic impedance. This is quite expensive and it's not in the pool and we can do without this. With multi-layer stackups you usually want to use top and bottom for signals as long as possible. That means the adjacent layers should be reference layers. You can see this here. We have a reference layer here and the outer layer is used for signals. Then by putting voltage supply and ground planes close together you create a really good capacitor for high frequency. This is something you can see here. We have the voltage here and ground there and we have a really good capacitor and the thing is you need this layer stacks need to be symmetric. That means if you put a solid plane here you also need to put one here. Otherwise it'll come to problems once the PCB gets produced. With less than eight layers the height is usually very high and this leads to rather large track widths for the typical characteristic impedance of 50 ohms. This might lead to spade issues during routing and we need to make some trade-offs for example, slight mismatches for the impedances or we need non-adjusted voltage supply and ground layers. You can see this here, the ground and the voltage supply layer are completely on the opposite side so there's really no capacitor there. But yeah, we need to make trade-offs. Here are some examples you can use. This one is a pool stack up from PCB pool six layer and this one is the pool stack up from Word Direct six layers again and here is an eight layer pool stack up from Eurocircuit. Also here you can find a slide with some PCB manufacturers. They are mostly European, Germanians especially. Some of these have, for example, Eurocircuit. You can directly see and choose the stack up you want. It'll give you expensive prices for the non-pool stack ups but if you choose the pool stack up, they will use this one. With other manufacturers, you should check this before that they really use this pool stack up. When doing BGAs, you usually wanna use dog bone breakouts. That means you divide the chip in four quadrants and add the wires for those parts facing to the edges of those quadrants. And this way you can see there is some cross in the middle where no wires are and you can use some, you can place some 402 capacitors in here and this works well with pitches of 0.8 millimeters and more, the pitches, the distance between the center of one pad and the center of the next pad. Also you should cover the wires with solder stop. This is explained here how to do this in EGLE. Minor clearance violations are usually not a problem. For example, I produced this one here with this clearance where the bought house only can guarantee this clearance. And you can say it's on my risk and produce it and it usually works. Design software, EGLE I already mentioned, there's a hobbyist version for up to six layers. Another cool thing about EGLE is that they use XML board files. Those are easy to read, understand and modify. You can use software to do this. In Lua you can simply convert it to Lua tables. Those are nested and later you can write those tables out as XML board files again. KeyCAD is free and open source and it's really great. Just make sure to use the Diva version, not the stable one because there are lots of new features in the Diva version. Save often and make backups because it's the Diva version. The layout engine is very powerful. You can push and shove. That means you can add a track and it will push the other tracks away. This is great for BGAs and more complex projects. There's a bit in Python interpreter and the board files are text files. Those are easy to read, understand and modify. There's also a bit in 3D viewer. The conclusion of all this is that's a lack of extensive professional software can be compensated for with three and open source software, custom tools and knowledge and high motivation. You can produce a great PCBs by choosing the right pool process and you can use this for very advanced projects. Reflow soldering is also something that can be done without expensive equipment. It needs some experiments and patience. So the further strategy is to invoke Hacker spaces for the soldering, for example, and to improve the software for the impedance matching and so on and to collaborate on such projects. If you have more questions, I think we do have 10 minutes left for the questions. And I'm also available in the Königlich-Bayerischen Amtsvillage here and you can also call me via deck. You just have to dial hunts, yeah. And so I'll say we start with questions. So thank you very much for that interesting talk. Your applause. I actually think that was quite a lot of pushing with a lot of physical background and knowledge you will need and not only soldering. And so building your own tools is actually quite cool and I think for sure there will be some questions here. So if you have questions, please come to the microphone in front of you and ask your question to the microphone. We still have 10 minutes for questions, please. Most newer BGAs have a pin spacing of 0.5 millimeters. Did you see any vendor that can produce the required blind rears? You need laser drill between the uppermost wires for that. Well, there are a lot of houses that can produce it, but they won't do it in the pool.  I think this will change in the future because it is more and more necessary. So if we today we think about six layers, multi layers, we haven't had this in pools in about two years before. So I'm certain there will be some steps towards this, but it's not here right now. Thank you. So the next question, please. That's a comprehension question, where you talked about pool stack up. Yes. As I understand that the different layers are pretty much identical. So I don't quite get the point where you have to be careful about what is the pool stack up and what is not. Would you elaborate on that? The thing is, here you can see some pool stack ups. This one is a pool stack up from PCB pool and this one is one from, it's the same stack up I think, but those build ups actually differ from the board house to board house. So I don't think this is correct what I wrote here because this is, yeah, I don't think this one is right. And the next thing is, once those, you need to really tell them to use the stack up they wrote on their webpage because sometimes the manufacturers, if they have a customer paying for a custom stack up and they have some place left on this board, they will put your project on this too and produce it with the wrong stack up for you. And for example, PCB pool sometimes uses a six layer stack up when you ordered a four layer board and it just won't use two of those layers and but it obviously it will mess up your stack up. And that would use problems with impotence within the stack up. Because the height will change. Okay, we have to be a bit of load balancing for this question. So the next two questions, please go to this microphone over there. Just less a question, they're more a small hint. If you can get a hold of a German university email address the commercial package Altium is actually available for around a hundred euros here and compared to Eagle and Keycard, it's at least worth a try, I think. Maybe in addition to the previous question, the guys from Altium realized that everyone is pirating their software and they decided to release a free version which is called CircuitMaker. It's currently in open beta. You can already download it if you sign up at the CircuitMaker website, circuitmaker.com. And it looks pretty good actually. It doesn't have any layer or component restrictions like the free version of Eagle has. Now to come to my question, well, question, remark actually, you mentioned the trick of creating a rectangle around packages of ICs to facilitate the alignment but I want to remark that for many Chinese manufacturers the alignment of the silkscreen layer is not always so perfect. And I already had a few instances where I indeed used the alignment of the silkscreen and unfortunately the silkscreen was a bit off and I didn't notice until the ball grid array switched one row of balls which is almost incorrectable. Yeah, there's some trick. You can look through the balls if you hold it against the light and then you will see if they are slightly moved against the paste but this only works as long as there are no other chips. Thank you for an interesting presentation. So we have still four minutes left for questions so the next question please to your microphone on the right hand side. I have a question about soldering. Do you have any suggestions for a double-sided soldering process with using a reflow oven? No, usually I do it that way that I put all complex components like BGAs on one side and I use the second side only for components which I can do with hot air or the normal soldering iron. Then I place one side in the oven and then I do the second side and for example with paste on a hot plate and with hot air this works well or with a soldering iron. Okay, we have time for another question or maybe another two questions please. Thank you for the talk. Have you considered ultrasonic cleaners for stencil cleaning? Well, you should then use something else than water I would say because it might not, yeah, it depends on the paste if it's water-solvable, I would say. But the lighter fluid really does the trick for me and there's also another trick you can use. You can add round corners for those pads. You can adjust that in Eagle and in some other boards too where the corners won't be perfectly 90 degrees angles but they will be rounded and this way in the corners there will be less soldering paste left afterwards. You can clean it better that way. Okay, I think we still have time for one more question. Yeah, it's just one thing about solder paste. Maybe I missed it but what I learned about solder paste is that it absorbs moisture. So if you have old solder paste you might end up with a garbled design because the moisture drives out the solder paste from the pad during soldering. So you should temper, you just make the paste on your design then put all the components and temper it at 80 degrees, half an hour in an oven and it's dry and then you can safely reflow solder without having sparks of solder coming out. Yeah, well, the tempering is, you mean during not the popcorn effect but for a normal, well, normally you don't need this with the solder paste available today so there are different waves that are recommended by manufacturers and there are also some waves that use some sort of plateau here with about 100 degrees. But I usually, so if you have different chips and every chip has another wave you should use you obviously have to decide which one you use and if the FPGA costs 50 bucks I'll use the one from the FPGA and it does the trick for all the other chips as well for me, so. All right, thank you. So maybe one more question, do we have any questions left? I don't see anyone standing on the microphones here so please give a big round of applause to Hans for this very cool talk. Thank you, thank you very much.


Hi everyone, my name is Jasmine, welcome or welcome back to my channel. Today I'm coming at you with another five book recommendations video. As always I will leave a link to the playlist with all of my five book recommendations videos in it in case you want to check any of the other ones out. I have recommendation videos for literary fiction, classics, historical fiction, fantasy, children's fiction, you get the gist. Today's recommendation video is going to be all about poetry and I'm pretty excited for this list. Whether or not you already love poetry and you've read a ton of it or you haven't read poetry at all, whether or not you want something relevant and hard-hitting or something more fantastical feeling, hopefully this list has something for everyone. So the first collection that I'm going to be recommending today is Homie by Danez Smith. This is the newest collection by contemporary poet Danez Smith. I have read and loved both this collection by Danez Smith and Danez Smith's earlier collection Don't Call Us Dead, which I actually recommended in my Pride Month recommendations video.  Their poems explore themes of self-identity, as well as tons of social and political issues that are at the heart of present-day America. This one in particular explores themes of race and queerness and violence and most predominantly friendship. If you've seen many of my videos, you will probably know by now that I am a massive fan of Danez Smith's poetry. They are one of the best contemporary poets writing today. There is no doubt in my mind. I know that they are being recommended a ton at the moment, especially in light of the Black Lives Matter movement, but I think they deserve all of the praise that I am here to add my voice. This collection is so important, it's incredibly relevant, it delves into the idea of otherness in many of its forms, and it is bold and unapologetic and inclusive as it does so. The poems in here are striking, the imagery is so vibrant, they also play around with sound and rhythm so effectively. While it's probably true that all poetry is better read aloud, this collection in particular just shines when you read it out loud. And as brilliant and superbly crafted as this collection is, it isn't inaccessible. If you haven't read much poetry before, you will still gain something from reading this collection, I swear. So yes, this is just a beautiful collection. I cannot recommend it more highly, it will shock you, it will educate you, it will affect you emotionally. Please just give it a go. The next collection I'm going to talk about today is The Bees by Carol Ann Duffy. I know that none of you are shocked, but this wouldn't be a poetry recommendations video from me if I didn't recommend a collection by my favorite poet, so here we are. This is one of Carol Ann Duffy's many poetry collections. It was published around a decade ago now, I think. As in all of her collections, this one explores a host of themes. We have poems about love, we have poems about political anger, we have poems about family, but throughout this whole collection there is the recurring imagery of bees. The poems in here are deeply personal, but at the same time they feel universal. The themes feel timeless, but at the same time extraordinarily timely. Her wordplay is creative and playful and so inventive, her imagery is sublime. And I love the way in which the bees are woven throughout this whole collection, it is fantastic. In some of the poems the bees are sent to stage, in others they are briefly mentioned, or there is just some illusion to them, but their representation of beauty and grace and what ultimately we should be protecting is present throughout. It's so wonderful. Carol Ann Duffy is just the best if you're looking for a solid, reliable poetry collection that is going to impress you and challenge you and be thoroughly enjoyable at the same time, then definitely pick this one up. The next collection I'm going to recommend today is Witch by Rebecca Tamas.  All set within a framework of witchcraft and mysticism. So this is definitely the strangest and quirkiest collection I'm recommending today, and I will say that this is the one that I've found to be the most challenging to read. The poems in this collection are super dark, super unsettling, super gritty. Some of the poems are hexes, some of the poems are spells, the language throughout is super visceral. Huge content warnings for violent and often filthy imagery in this collection, so please bear that in mind. But every word in this collection feels so intentional, sometimes the poems are quite soft and lyrical, other times they are super sharp, and that is something that I really enjoyed whilst reading. And throughout all of this, this collection is really intelligently and wittily exploring tons of really important, wider, relevant themes. As for why I found this collection to be quite a challenging read, the poems in here are definitely quite obscure. A lot of the time I found myself to be just taking the poems in on a surface level, just basking in all of the sounds and the imagery. And that is great, that is not necessarily a bad thing at all, but I just know that there is so much more in this collection that went over my head. And I'm sure a lot of that will surface for me on a reread, which I'm really looking forward to. But honestly, this collection just provided me with such a unique reading experience. It was incredibly evocative and very powerful. And so if this one sounds interesting to you, I would definitely recommend giving it a go. And if by any chance any of you have already read this collection, I would love to know your thoughts on it. The fourth collection that I'm going to recommend today is The Perseverance by Raymond Attrabas. This is a debut contemporary poetry collection by British Jamaican poet Raymond Attrabas. It explores the poet's experiences being deaf, being biracial, and the death of his father, among other things. So firstly, this is a super valuable read when it comes to the topic of deafness. The collection explores Raymond's own experiences with being deaf as well as deaf history. It also includes illustrations of various signs throughout. I think it certainly shines a light on a lot of the ignorance surrounding deafness, at least in my case personally. The idea of living between two worlds and that space in between is also something that is explored highly in this collection. Not only regarding Raymond living between the hearing and the deaf communities, but also living between two communities culturally. The idea of not being British enough or not being Jamaican enough comes up a few times. As for the structure and the language use in the poems, they are pretty experimental, I would say. They definitely gave me John McCullough vibes, who is a poet I adore. So yes, I would definitely recommend picking up this collection. I really enjoyed it. And as a debut, I thought it was particularly great. Raymond Attrabas clearly has tons of potential and I think his poetry is just going to get better and better. And finally today I'm going to recommend to you Kingdomland by Rachel Allen. This is Rachel Allen's debut work and it is a very fantastical feeling poetry collection. It is full of surreal imagery, strange incidences, there is a lot of violence and animal imagery, but throughout the collection it also speaks to many very real everyday occurrences. This collection definitely has quite an eerie feel to it. All of the lines are blurred. It has that feeling of the uncanny running throughout it, where things feel very familiar, but slightly off. The poems in here ultimately felt very haunting and beautiful to me. There are tons of descriptions that just sweep you up. I will say that I didn't have the strongest emotional connection to this collection. That isn't what this collection did for me. I didn't really relate to a lot of the poems on a personal level. But if you are interested in surreal, slightly weird poetry that evokes wonderful imagery, then definitely give this one a go. So there we have it. Five more of my poetry collection recommendations for you guys. Please let me know if you've read any of these collections and what you thought of them. And of course, please let me know any poetry recommendations that you have for me down below. Thank you so much for watching everyone. I really, really do appreciate it. Please don't forget that I'm going to be doing a Q&A soon to celebrate 5k subscribers. So if you do have a question that you would like me to answer in my Q&A, it doesn't have to be about books. It can be about anything to do with my life. Then please let me know down below in the comments. I'm really looking forward to filming that video. Thanks again guys. I will hopefully see you soon in my next video. Bye!