All right, separatrators, good afternoon and welcome on back here this Monday, June 13th, shortly after 2.30 PM Eastern time. Welcome on back here for our afternoon meeting. Great to see all of our students and members that like perhaps rejoining us live inside our trading room. I'll tell you what, there's not much to look forward to, perhaps, on a very gloomy down market day. Might be as good of a day as I need to get some errands done, get the gardening done perhaps. Great to see Nina joining us live right now and a bunch of us joining us otherwise. And for all of us joining us live in social media if his book live YouTube likewise, great to see you folks. But not a whole lot to look forward to here normally on a day like today. Obviously, Dow is down 600 points heading into the market open. Ended up seeing much rather of a drop off shortly afterwards, right around 10 o'clock. We ended up seeing the S&P ETF spy just continue to break down there. It looks like we're seeing a lower high and potential lower low coming up here, at least more of a local lower low. We'll see if it ends up getting to the low of the day by the time the market closes. But it definitely looks pretty strong on the way down here. So I'll tell you what folks, we have a lot to talk about here. And not just in terms of what's on the docket for this afternoon, going through the percent gainers and losers lists. I ended up trying to do the SunFraud day I wanted to actually I should say. But I ended up slip past me. I forgot to do it come Friday afternoon here in the afternoon meeting. I want to go over the spy or rather action not just the spy but the S&P as a whole, the S&P 500 index. We're going to show you the chart across the last 50 years. The pattern that I showed probably about a month ago. We introduced this about a month ago, a FIB channel that we had back over the last 50 years. And pretty interesting to see how it's progressed over the last couple of weeks even. So with that, a lot to talk about here. The AGI trade, hey, not everything's dropping and going with the market perhaps. AGI, AgriForce, the stock that we're actually pretty familiar with, I'm actually going to jump back to the monthly chart there. Just give me a quick moment. But for right now, the daily, you could see that the stock back from October of last year, back from mid of March. Just even recently, you're heading back into the mid of May. Just on and off, we've been following the stock off of news and off of just big volume. We started this meeting. It was kind of slow inside the trading room, kind of slow within the market. I'm just trying to fish around, scan the market. And I saw AGI on the gainer side. It was trading a lot more volume compared to what it was from late morning, early afternoon. So I'm just thankful I clicked on it, I guess. Thing was already running up pretty nicely. So hopefully there's a lot more left to this trade here, the AGI. Definitely I'll put this on the afternoon list here just to begin. It doesn't hurt us to do that.  I do want to, like I said, talk about the S&P just at the end, do a little charting on that, just more so than anything. All right, so the dawn trade will kind of skim through dawn from earlier today. I mean, it ended up popping up pretty nicely in pre-market. It popped up a little bit after the market opened up, took a little while for that squeeze actually, but obviously it wasn't really too good afterwards. So I was pretty fearful of this just plummeting right back down, but it's actually done worse. It's actually doing worse than that because if this ended up tanking right away after the market opened, or if it ended up tanking just even earlier, at least we would have taken our eyes off it. This damn thing's been teasing us all day for another move back up, for another big move down if you're able to short it. It's just done nothing. So obviously now at this point we're not gonna be as keen to follow it here for the afternoon, but make up your mind now at this point on. HILS, this one obviously more on the way down. So this was kind of washed from mid-morning even. OPTN still kind of hanging near the highs right now. A bit of a spotty chart though. So not too particular about that. XO, hey, this one ended up having a nice little pop after the market opened up. So briefly to cover this, broke under and then right back over to from there, ended up making a huge run. More important, well, not more. At the same time, as it continued to push up you may wonder, well, how much more could it keep pushing up? Am I able to still jump in on this trade? It's a matter of flipping resistance into support. Seeing higher highs, higher lows, seeing resistance turn into support. So with that, we ended up seeing actually this break above 235 and it was already at like 250, 252 at the time. And I'd said at that point like, hey, on a pullback this needs to hold over 235 area. Well, thankfully for this one you can't say it all the time, but for this one it ended up proving so. It held support and led to a nice pushback up. I was down from this morning after the market opened up and thankfully this was one of the few trades that led me to turn back into the profit or turn back into the plus. So I ended up getting out on this trade under 260, left a little amount on the table there, but it was a great entry from past resistance 235. Now late to the party, but still able to grab a good piece of the pie. And right now this thing is making a bit of a lower high still across the high of the day. So not fully sold on it for the afternoon. If it pops during this meeting maybe. RJF calling out the AERC trade. So yeah, we were calling, we were watching this going into this meeting. We had our eyes on it obviously from the market open. It was active in pre-market, but I wasn't really too thrilled about it. Wasn't on the pre-market list. Wasn't on the morning list. But hey, it's on our side list for a reason. The stock exploded back from the beginning of last week and really was holding strong since. So no, we were hopeful for that pop, but we decided to focus on Coinbase, Dawn, Blue, Redbox obviously also. But this ended up popping and we called this out pretty early on after the open. So it treated us pretty nicely at least with the initial breakout off of 13, but from there, well, hey, look at the order book now. It's what the order book looked like after the market opened. It was pretty tough to trade after the initial breakout, right? So again, you hope to see resistance flipping to support. Looks like just a moment ago, you had your bounce off of 14 area. For as much as this pushed up over the last three to five days or if not more, you know it's gonna tank, right? Now at the same time as you say that, right? And it certainly will at some point, the stock and we've been talking about this point as well. Stock drop from 110 down to sub two. Perhaps there's more recovery room on the way up. So you definitely hope to keep this on your radar, keep it on your side list. And we've had a great eye on the stock throughout most of the day for this reason. It's pushed up pretty nicely. So you know what? I like it right now, the AERC trade. I'll put back on the list there, RJF. Keep it going. CISO, not a whole lot happening here. AGI, we already talked about that, let off the meeting. Keep it going, folks. Now really quick, little housekeeping note. I wanted to do this mid-meeting while I have a lot of us concurrently on YouTube. Tomorrow, tomorrow morning at 11 o'clock Eastern time, join us live. We'll be conducting our weekly trader stock workshop, which we normally host live inside our trading room. And for all of us there, you do not need to go on YouTube. You could stay right inside the trading room as usual tomorrow. Trader stock is our live weekly workshop that we almost always conduct exclusively live inside the cyber trading room, maybe two or three times across the calendar year. We'll spread the love and show it out for all of us on Facebook live and YouTube. I think it might be YouTube only if I'm not mistaken actually. So pardon me for saying that, I'll retract that. YouTube only, so feel free to join us on YouTube, that being youtube.com slash cyber trading you. And that'll be tomorrow at 11 o'clock Eastern time. Now with that, the blue trade. The stock was shortable on my platform going into the open. Unfortunately, the stamp thing tanked so fast at the market open here. I had zero time to get the entry off from six or 625, I think the level I wanted was. So it ended up in ultimately making that move before the open or right as the market was opening. We normally tell our students, and I like to preach it myself. We tend to wait the first three to five minutes after the open before we start seriously, looking to enter trades. So I wanted this to retrace back up towards six after. It didn't get close enough and then just went down without me. It was a tough, tough missed opportunity right there. I'll tell you what though, this stock is still dropping right now slowly but steadily, it's still shortable on that platform. I, you know, it's still tradable in that regard. So I don't mind slipping the blue on our list here again and if it fails to break lower and if support does hold, then maybe we do see a bigger and better bounce heading into the close. We did happen to have a pretty good bounce earlier today though. Another missed opportunity very briefly for me here actually, just to show you that I had a FIP retracement set from the close back from the past trading day before it was halted up to the pre-market high and this freaking thing ended up laying maybe like five or four cents, maybe even less like three cents above the 61% retracement or 71.6, I think it was. Just, I wanted the under and over, the slingshot and for all of us live inside the trading room, you folks know what that means. I just didn't get it. It just held right above it, hovered right above my line and it squeezed on up without just another big missed opportunity on this thing. But again, it's still tradable. Hopefully there could be one last chance to follow this. Looks like so far on the way down heading into the afternoon. So, you know, we have AGI, we have AERC and we got the blue stock so far. All right, market is obviously in a range here for right now as it has been. So, you know, I don't know how much of an exciting close we'll have here should that range look to kind of contain the market. Red box from earlier today. This is the second of three stocks that got me out of my hole this morning and it was more heading into the mid-afternoon here. I wish she was in the room. I've been looking for in the trading room earlier just coming off our coaching session. So, I was on a call with one of our students, Catherine, going into the one o'clock call it was. And at the time we were talking about just, you know, basically what we normally talk about coaching and in traders talk, just more of the preparation aspect before the market opens and how you could look to use those levels to try and follow a stock throughout the day. Right, follow along. All right, let's flip back to a monthly chart here on Redbox. I've been following this range of levels for the last like, you know, few trading days at least. But, you know, back from October of last year, the monthly close, 14-14. You can see the data box right there, 14-14, the close. Then the open, just, you know, November, 14-25. What's the low of the day, folks? 14-23. What that essentially means is this ended up snipping under my line at 14-25. And I was watching this with Catherine when it was breaking under 15.  So thankfully I was watching this right then and there for the crappy morning I had, jeez. You know, I guess I wasn't watching the right stocks the right time, but nonetheless, this was like the perfect gift and this was the main thing that led me to flip right into a profit. So with that, I was in from 14-25 exactly. It took half out under 15, half out right at 15-23. Left some money on the table. Don't really care at this point. Just, I'm gonna make sure I remain in the plus throughout the day. I'm gonna trade like a chicken heading into the afternoon, I think. So, you know, for right now, the red box trade here, I don't know, it's like pretty flat. Maybe it could pop. Maybe. I'm not a big fan of maybes. So for right now, I'm gonna pass on this. All right, what else we got here on the gator side, folks? I mean, again, markets obviously in a range. Dow is down 600 heading into the open today. But, you know, that doesn't mean that we're not gonna find, you know, anything that's moving on upward. We just had AGI. Tell you what, actually, as I'm just giving through this list, a lot of ETFs here. A lot of ETFs, here's a logo. Just wanted to look at this one here briefly. All right, let's hop on over to the losers list with that in mind. I mean, geez, it's like really ETF written here. So I'm sure the losers list will be similar, but let's just see if there's any familiar names that are down big, right? Maybe Roblox, RBLX, maybe, you know, an AMC or an EO. Obviously the Bitcoin stocks took a huge hit. You know, coming up, we're not gonna do as much of a review on Bitcoin, just to let you know. We're gonna do a lot more of it on the S&P. And I'll explain why in a bit. But MicroStrategy, one of the major, you know, Bitcoin holding stocks or companies out there. Michael Saylor is getting awfully close to getting, or to the beginning of his liquidation. I think he said, yeah, Bitcoin has to drop all the way down to 3,500 in order for him to, you know, get rid of his entire Bitcoin portfolio to be fully 100% liquidated. So when they're talking about, you know, Bitcoin dropping down to 21,000 and Michael Saylor getting liquidated. Oh no, he's gonna be fine so long as it doesn't really drop down that much lower than there. Obviously he wouldn't wanna be in that position to begin with, but you know, I think he'll be fine, this company will be fine. I have no position at MSTR, but obviously Bitcoin will briefly talk about here in just a bit. Geez, a lot of stuff hard to borrow otherwise.   All right, so let's do a rummage through here really quick, folks. AMC, how are we looking? Nice little bounce back up on AMC. Don't get me wrong, it's tradable, but unless the markets are really squeezing on upward, not really too big of a fan. NEO's at the low of the day and down over 11% and it's shortable still. So this is as good of any stock to follow heading into the afternoon. Any stock that's, you know, respectively at the highs or at the lows, you know, granted, markets still in this range, but NEO is obviously showing great weakness. LI is not showing that much weakness right now. This hasn't really, you know, trended back down much just yet. I'm not just a sucker for NEO, folks. It actually looks good today. How about that? All right, so NIO, I'll put exclusively on our list. Maybe a ex-pev here, familiar, similar stock to NEO. Not really looking as good either. All right, that's fun. Bobby on YouTube asking about AGRI. So we already covered that. We started the meeting off by going over the AGRI trade, Bobby. So that one's already on our list. RJF asking about COGT. Hey, COGT, this looks great. So obviously, we're going from top to bottom across the gainers and losers.  So for right now, this goes right on our list. Now the question is, where can we find our levels on this trade? $10 is major resistance, you would assume. 10,000 share order currently on the ask there. It already broke over 10, so you started to see the buying coming in already. But, you know, just even looking at the monthly chart here, you could see, you know, pretty big resistance looking at the monthly. I mean, just way ahead. I mean, we're talking like 14-ish, 1390. Obviously, I'm not going to hold my breath and wait for that just yet. You know, it still has to really make a strong break over 10. I think it's going to pull back first and then perhaps later on make the retest. But, you know, a really good call. I like this one, COGT and Norman too inside the live trading room. And I can't watch both at the same time. Looking back on both right now, Norman had called that out just earlier. RJF on YouTube pretty much at the same time. All right, so folks, if there's anything else, we'll wrap it up at the end. I told my colleague Rich to clip this coming up just so we could have this on our YouTube channel. So for recording purposes today would be Monday, June 13th. Now, I bring that up first because really quickly, we're going to talk more about the S&P 500 index, namely, and just we're going to show you the chart dating back to like even 1935, 1930, but really focus over the last 50 years of the S&P chart. Now, with that though, I want to bring up just really briefly for all of us joining us right now. We had done this video here. I'll show you right now this video. And it's posted on our YouTube channel. We posted this video back on January 22nd. Just what if the Bitcoin bull market peaked then? Well, we had to react at that point and we had to go over all scenarios. We can't just be a permable our whole life here and just expect Bitcoin to go up if it's not. Now, I bring this up because essentially, Bitcoin has a very strong correlation with the S&P more now than ever. It always has had a great correlation, but recently over the last several months, we've had a stronger correlation between Bitcoin and the S&P, between more institutions dipping into crypto and Bitcoin as a whole. But nonetheless, it's to say that we were anticipating should Bitcoin fail to get back over 40,000 and hold above it and run from there, for it to drop down as low as 18, 17,000.  You could type in Cybertrading University Bitcoin and it'll be one of the featured videos right there. You could always like and subscribe right on our YouTube channel, just to be as most up to date as possible with what we're putting out on our YouTube channel. But let me bring up the S&P chart now because obviously from Thursday into Friday of last week and then obviously into pre-market this morning where the Dow at least was down over 600 points. I didn't get the exact number for the S&P heading into the open here, but markets were down big once again today. Now, I had shown this exact chart probably about a month ago. It wasn't clipped out and posted on our YouTube channel though. So that's what we're looking to do right now. But dating back to 1974, 1975, the bottom there all the way to basically present day, this right here, A is a fifth channel between the two major dip points from 1974 and the 2008-2009 recession to this peak that we had dating back to the dot.com bubble, the peak of the dot.com bubble. So essentially what this creates is an extended Fibonacci channel. Now, this is really good for swing trading, really good for investing. I'm personally more indicator based when it comes to swing trading. Now I say that just right away because coming up later on this year, if not even this month, if not mistaken, Cyber Trading University is gonna be beginning to launch a swing trading course. So for all of our members here, at least be on the lookout for that. But we're gonna be talking a lot about this, a lot about Fibonacci, a lot about different indicators. That's more of a me thing, more of a Josh Levitant thing than a Fausto Puglisi thing, right? You know Fausto is not an indicator guy. But nonetheless, here's what I wanna show you with this Fibonacci channel. This is the pretty interesting part about this. Let's even just start back from 2010 onward from the bottom of the dip point here. So since it's pretty interesting, we ended up seeing a resistance hold here pretty nicely. Resistance here got flipped into support over time. We ended up seeing a gradual move up. This essentially is COVID. So we ended up seeing a major shake down at that point. It ended up going under and over this line here within the channel and squeezed back up. Now here is the discouraging part about this, if anything. And I got a couple of ads here probably in between. But here is the discouraging part about this exact Fib channel. I would have wanted to have seen a false breakout at some point over time here. Because at least the false breakout shows potential buying interest, shows interest above that price. Folks, we got zero interest here. I mean, it didn't even come close. So what happens? It certainly seems like the momentum ran out within the market at that point. So we ended up seeing the beginnings of a pullback over the last several months. This is a monthly chart. So we ended up seeing it come back down to the 61.8% retracement line right here. Now it was just over the last month and a half, or obviously much lower from there at this point. And it only seems to be as if we're making a move down towards the 50% retracement line. So when was the last time the 50% was holding pretty nicely? Well, it was right back from here 2014, a major resistance point. Like I said, it got flipped into support a couple of points here. We can't really count COVID. Can't really count COVID here, folks. Obviously disasters happen and life happens where you happen to see major catastrophic moves that could affect the market. So that's what happened there. But just to say generally speaking, that 50% retracement line was holding pretty well from like 2010 onward. And I know this Fibonacci channel was built within kind of this range here, but even look what happens beforehand, before around like the late 90s or late 80s, early 90s, that 50% retracement was holding pretty damn slick, wasn't it? Little food for thought. So if there's such a correlation between Bitcoin and the S&P, it was more now than ever. And perhaps there could be a decouple over time, but I'm not gonna wait for that. I think that there's strong correlation enough to where we can anticipate the dip point on Bitcoin to be based off the dip point on the S&P. So with that, that brings me to my next set of indicators here. You have the EMAs, the blue and the orange. Yeah, those are like Met colors. New York Met colors. I don't know if anyone's a baseball fan.  I'm a Yankee fan. Anyway, with that though, the blue, well, considering we're on a monthly chart, the blue represents a five-year moving average. Essentially, it's a 60-month moving average, 60-period moving average. And then the orange is double that. So think of the blue as a five-year moving average and the orange is a 10-year moving average. I find this to be really important because even dating back to like the 50s or 30s, I don't think there's been a singular point where these two have even crossed. So that speaks for itself. And then from that point otherwise, there's been several points where it's broken under these lines, of course. But with that said, that leads me to think that there could be a lot more room down on the S&P before we happen to see continuation on the way up. There's a bunch of folks that I've been following on Twitter for crypto and Bitcoin who are quite bullish over the last few months. And these are people who had great predictions and calls over the last two, three years. I would reference them to you. I would recommend them to you. Perhaps in our chat where I'll talk to you about them later, the files I have on Twitter. But they were wrong. Obviously we saw continued weakness within Bitcoin and within the S&P as a whole year. So it would not shock me over the next several months. It could be the next six to eight months to where we happen to see the S&P pull back down towards that 60 month, that five-year moving average in blue. That would tie up pretty nicely with that 50% retracement line, wouldn't it? Now they're pretty much there right now. So I would think of that as a major support level going forward, at least within the S&P. All right? Alrighty, folks. I think that just about wraps it up for me at least across the S&P once more. If you wanted to go back on our analysis on Bitcoin in particular, we've done a video dating back to late January. We did a few from that point, but really that was the first one we put out. And so far that one certainly gives you the best idea as far as where we personally anticipate Bitcoin to bounce off of at this stage. So with that, I'm following the S&P more intently now than ever, just given the correlation. Are there any other stocks, lastly, folks, that we didn't have a chance to cover before we finish up? I have a coaching call at three o'clock with one of our students who I did not send the link out to yet. So Jim, be on the lookout for that. All right, folks. I think that just about wraps it up for me here once more for all of us on YouTube. Please join us tomorrow. That being Tuesday, June 14th, tomorrow live at 11 o'clock Eastern Time, right on YouTube. We're gonna be doing our weekly trader stock workshop once more for all of us inside the live trading room. You don't need to go anywhere. We're gonna do it as usual. So if you're inside the live trading room tomorrow, I'm gonna come on right at 11 o'clock as usual. It'll just be also out there on YouTube as well. So for anyone of us on YouTube that would like to join tomorrow and have questions or trades or stocks or symbols altogether, crypto or indices or equities, whatever it may be that you would wanna cover with us here tomorrow live, send it over to josh at ctutrading.com. If you have not yet liked or subscribed right yet on our YouTube channel as well, just right like on the yellow banner below says, just please do that as well. That really helps us out as a whole. But otherwise, I look forward to seeing all of us there tomorrow morning and then for all of us just live inside the trading room, I will be back on the mic. If not at 3.30 Eastern Time, I may tag Rich in for me. So if I'm not on at 3.30, then I will see everyone coming up tomorrow morning then. Talk to you soon. Come a cyber group member today. Just click the link below and receive all these amazing products and a world of knowledge for just $9. Do it.


Yeah, here you go. Okay. Okay. I see myself now great Thank you and welcome everyone to the first talk of PyCon. I'm so excited. I hope This will be a very interesting Talk for you Especially since we are doing this online It's it's new for me as well. So please excuse me if I'm not not being able to give you that feeling of being there But we are pretty close to right. I mean if you have any questions, please put it on the chat I'll be happy to talk about it in the end So on to the talk the talk today I would like to talk about is how I built a ray tracer in pure python. Thanks to the great background from a beyond that But just a little more about the background in case you don't know what I'm talking about This talk is about how I created a ray tracer called pure a pure is just a abbreviation of pure ray tracer and that pure part I would be explaining in a bit But basically what pure refers to here is I'm just using the python standard library I won't be using any external third-party libraries Which includes numpy or any of the graphical Libraries or even an image writing library like libpng or for jpeg writing it's all in python and The outcome of this was not just this particular library. I also presented or published six parts of how to make this ray tracer library on YouTube This was like a tutorial series aimed at intermediate level Python programmers and It took me a pretty long time to do it It took about 12 months for me to complete it But at the end of the day the response was phenomenal like I did not expect it to have more than about a thousand views But it's now clocking more than 17,000 views and a lot of people are sending a lot of positive things about it If you want to see this tutorial Please scan the QR code which you see right now on the screen or just type on your open your browser Just type bit.ly bit.ly.ly slash pure P U R A Y and You will be taken to the YouTube playlist where you can start seeing this video or Start from part one and go all the way to six parts by the end of six parts You should be able to create an image like this This is a fully retraced image in 1080p Some of the things that you can see here are that there are Rendering of spheres. There is a rendering of a checkerboard pattern And if you look very closely, you can see that there are reflections within reflections So there's the reflection of the red ball within the purple ball and inside that reflection You might actually see the purple ball. So this is like multiple depth recursive Structures which we have used here Just to see the kind of positive response over here I have just put together some comments that have got Both from new people who are new to Python programming as well as people who have been using Python for decades And just wanted to do something fun And interesting and they just tried this tutorial and they found this to be a great weekend project If you are a beginner, it might be like a mini project as I call it For for instance, it might take a couple of weeks for you to complete it if you're trying to do it in a very leisurely manner, but you might not only have something that is Informative that's knowledgeable as well as you might have some fun in doing it So that's why I just wanted to show you how people found this In the next couple of minutes the whole talk is structured into this format I'll be talking about what motivated me to do this I'll also talk about some of the challenges. I faced when I was trying to do this and I will share some Tips or some of the tools that I used for making video tutorials in case You are interested in making a video series or something similar to what I did Making a video is a lot more involved than other mediums and I think there's very little information out there to help people guide you in this Process and finally I'll tell you about what my learnings were what the post-mortem of the project is now that it is over and What I would do better in in my next future projects A Quick introduction about me. I beat it a pretty good job there as well I'm the author of the book Django design patterns and best practices Currently now in its second edition. I've been a speaker for multiple conferences including PyCon from the very early days Back when we it used to be conducted in the meat space as we used to call it Than a virtual event I'm an engineer by By education as well as a products person in my day job I'm a senior product manager at a company called unisys where I deal with multiple server technology products I'm also a dad for two beautiful children and I'm based in Bangalore. Now, I would like to tell you how it all started right as Simple as it may be or as It happens in many of the cases it all starts with a tweet I had a weekend free in which I was tinkering with some graphical code and I thought it might be a cool project to do and I tried creating a ray tracer by reading some theory materials and Made my render in about 10 minutes At that time I was using numpy and as you can see The render is just a very simple white sphere on a checkerboard and Just for a bit of ego massaging. I just write written my name also using spheres In on the floor and I thought it'll be cool to share it with others. So I just shared it on Twitter and I just Waited for what kind of responses came out One person who actually asked me this looks really cool. Can you post a tutorial on how you did this? So I jokingly replied to him saying that aren't there enough ray tracing tutorials published every year or every month That why should I add to that and I left it at that? I mean, I didn't think too much into it Then many years later, I should say this was 2015 I think about 2018 2019 my daughter is about 11 years old now She was about nine then she was interested in learning Python. She wanted me to you know teach her Python Because I was so enthusiastic about Python. So The funny thing there is You might think that Python is a great beginner language It is actually but it's still very difficult for a beginner to understand, right? A beginner might find it extremely Challenging with some of the simple concepts which happen or conversions which might happen for example when you divide two numbers you might get sometimes the wrong answer like Instead of nine divided by three returning three there might be like a floating point number like 2.9999 And if you really you can simply explain it by saying that you know Python Is using floating point numbers and inside and floating point numbers have these kind of problems or you can go really into the depth of this You know saying that you know, there are there are these kind of errors which can be corrected and all that So that is all very daunting and I would call a leaky abstraction that even if you are a beginner Or even if you are an experienced person you might face When you are using Python and then there is a big problem a beginner phases that is When you are faced with a problem, how do you really break it down? How do you really start from something like build a web application or big build an application? And that starting problem is enormous. How do you design that problem that is very difficult if you're a beginner and if especially if you're coming from a non programming background as many people who use Python are You might be a scientist or a teacher. You might find it very difficult to use when you're using Python Or any programming language for that matter. The other thing I noticed when I was teaching my daughter was there are two different kinds of Python learning materials. The elementary level, which is basics of Python programming language, which might tell you this is a print statement does an if statement. This is how you Write loops and things like that and the advanced level, right, which goes into really specific topics like how to do asynchronous programming in Python, how to do web development in Python, how to write type annotations in Python three things like that. Now I would say that You know, the, the big gap in between is not really addressed here. So somebody who is using the elementary level Material might see that this is really not very intuitive for somebody who is, you know, learning the programming language. I would say learning programming to be exact. So if you're already familiar with a programming language like see or some other language, you might find it intuitive to understand. Okay, a conditional statement is used using if instead of using curly brackets, you have to use indentation. But what beyond that, like, how do you really do problem solving that I'm sorry, that is the part where I feel a lot of tutorials, a lot of learning materials are lacking. How do you take a very difficult problem and break it down. Now, I would say majority of the people are in this category, because if you're a beginner, you might read the basics of Python in a couple of days and you're cross that beginner stage. Whereas to become an advanced Python programmer, you have to spend so many years or you have to do so much of coding. So most of the people are actually in between and the learning material is actually not catered to that. And even if it is catered to the intermediate level people, there are some problems with that, which is what I'm going to talk about next. So what are the problems which I see with most learning content which involves which are for intermediate level. Now, remember an intermediate level content should be about taking something like a project from end to start, sorry, from start to end. So it should be like building an application or a web application or a game or anything. It should lead you step by step from from very beginning to the very end. And it is kind of like a project based approach, which I would say is ideal here. Now, to understand what is the problem with most of these materials, I would like to take you to a very well known model in human psychology called fog behavior model. I came to know of this because of my product management background and I'm interested in how users think about a product. So it is not just for under the actual model is for understanding how human behavior can be changed. For example, you want to learn a new you want to develop a new habit like I want to work out or do exercise every day and I'm not doing it. So how do I change my behavior. But this is also interesting. If you want to build new products, you want to design something that is human centric the fog behavior model really helps. If you look at this model, you'll see that on the x axis, you have ability that something that is hard to do do something that is easy to do. And on the y axis, you have motivation, something that is low, not very motivating and something that is highly motivating. Let's look at a Python learning content. Most of the time, the ability is not an issue. Python is very readable to one. And if you just read, even if you have no programming language, you understand that, okay, if statement should be some condition, a while statement should be something like that. And there's not many punctuations or special characters. So you might be able to read it. So on the ability side, it might be easy to do so you're on the right side. But on the motivation side, is it really motivating? I mean, is it something that you would like to do and you would like to do for a very long time without any sort of Other external and extrinsic motivator. I feel that this is where most of the content falls below the line. So you can see that there's a curve which is called the action line. And if you're below that, you really fail as can see triggers fail here. And if you are about that, the triggers really succeed. So a successful or a very effective learning content should be about the line. It should be motivating as well as it should have the ability or the person should have the ability to do it. Now, how do I put it in very simple terms. I would put it in just two questions like is it easy or is it cool. Now, is it easy means that does not mean that it should be too simple or too trivial. It should be in the light right level of difficulty that you feel challenging that you want to do it. As well as it's not so difficult that most people leave it midway. So some tutorials, they start very easy, but in midway, it becomes too difficult that you know some people drop out. That is very important to take care of. And the second thing is, is it cool.  Can I show it to somebody or can I share it with my friends. Everybody knows that traveling salesman problem is a great problem to do in computer science. But once you completed that successfully. You show that completed solved graph. Your friends are not going to be impressed right and they'll be like what is this. But if you actually have something that is visual like you have built a game in Python or you have built some Cool graphic demo in Python or you have done a rate racer output. People, even if they are not programmers, they'll look at it and say, wow, this looks really nice. How did you do it. And they get interested, right. So that motivator is actually going to motivate you till the end of the project like, okay, I have to do this. This is the outcome that I'm trying to create. And that is actually going to drive you. Now, by no means, this is the only rate racer implemented in Python. So if I do a quick research, I can see that there are a lot of rate racers which have been written in Python and You can see that you have a n number of things on open source GitHub repositories as well. But what I have tried to do here using puree is to do everything in pure Python. Now, the question is why I'm stressing too much on pure Python in in this case it is because I'm looking at that from the audience perspective from somebody who's learning Python perspective like it has to be Something that does not involve that does not task the person to learn and another library like NumPy. Already you have the cognitive load of learning a language, a programming language. Why do you want to add in another cognitive load of learning a third party library like NumPy. Now, this might be non trivial for many people. That's why I very deliberately try to keep away from any other third party library, even if it means you just have to learn the API. Second thing is very easy to find out what the source of information is. If you're only using the Python standard library, the Python documentation is all that you have to reference. You can download an offline copy of it as a PDF or nowadays you get it as an EPUB disconnect yourself from the Internet and start doing it peacefully. Now, I find doing disconnecting myself from the Internet to be very important because it's quite distracting. There is a lot of there are a lot of things social networks and all sorts of distractions online and if I disconnect myself. I can actually do a much I can be much more productive. So if I say that I'm going to use only Python, just open the Python documentation, which is installed by default in many cases, and you just have to go through that. Of course, when you hit a problem, you might have to check you might have that temptation to check on stack overflow for that problem for that solution. But I would say resist that temptation for some time, try to find out what the solution what the problem is actually caused by and try to do some troubleshooting yourself. This is important because if you don't learn that crucial skill of troubleshooting and debugging, you're not really going to become a very effective programmer. So this this approach or strategy strategy of just using Python is very deliberately for you to do that. And another thing is that it becomes more readable. You understand what is more pythonic here. In my personal opinion, NumPy is not very pythonic. NumPy is actually influenced by array based programming languages like APL or J, and a lot of those ideas have come directly imported into NumPy. Same problem with Pygame. Pygame is an SDL is based on SDL, which is based on C, and a lot of C conventions come into play. Whereas if you use pure Python, you can understand what is pythonic and translate those concepts into other areas. And finally, there is this problem of security. A lot of people might be hearing about what is called as typo squatting, where you try to install something and you make a typo and you have installed something that an attacker has put in like a malware. So that's something to think about. Now, when I used Python, what were the challenges I felt? The first challenge was the problem of plenty. A lot of programming languages offer multiple ways to do the same thing. And this often leads to analysis by paralysis, right? This was the problem with the programming language, Perl. It offered multiple language constructs for doing this one thing. It was called there is more than way to do it. And I feel there is a creeping feature, feature creep happening within Python as well. And now I'll give you the example in a raytracer context. I want to create a vector, which is to represent a three dimensional point, which has just three components x, y, and z. I can use a number of data structures here. I could use a dictionary, a class, or if I want to make it even more optimized, I could use slots, which are faster than classes. Now, which one did I end up using? And how did I go about this process? I actually show it in the tutorial, but I actually tried all the different implementations. In fact, puree is currently in its sixth or seventh rewrite. And I've rewritten the entire raytracer multiple times and compared their performances to see which is best. But I always went for readability rather than performance. And that's why I ended up with classes. The second problem was I needed to use object oriented programming. Now, I'm not a big fan of classes. I wanted to do the raytracer in function functional style. And there are a number of problems with Python. If you want to use pure functional style, one of the problems which is solved in other functional languages like Haskell is laziness, right? I mean, if you are copying very large data structures, which happens a lot in image processing that you're dealing with megabytes or sometimes even gigabytes of data within memory, it all gets copied. And there are ways to avoid that in Python, but you have to jump a lot of hoops and instead of fighting against the language, I thought, why not use object oriented programming and embrace it, right? The other problem was automatic integer to floating point conversions and other sort of conversions, right? There is something happening within integer space as well called big num conversions. All these conversions just add to the memory and makes reasoning the problem very difficult and I had to be very careful to cast it to an integer where an integer is expected instead of automatically converting it into float and things like that. So all these challenges are actually because Python is trying to be more friendly, but sometimes it gets in your way. And of course, I have to talk about the elephant in the room, though it's a very tiny elephant in that bullet. It's that the programming language Python is actually slow when it comes to CPU intensive tasks.  People are like, wow, you're going to use a language like Python for this. But as you would see, as I found out, it's not really a problem if you have, if you broaden your mind to other implementations like PyPy and things like that. So it's ultimately a matter of optimization. And now my racer actually runs in less than 10 seconds or five seconds to render a 1080p image, which is pretty acceptable according to me. And I would say that that is good enough if you're trying to create your own racer for the first time. A very little time to talk about art of video presentations. My process is kind of something like this. I do the coding first. I do the scripting after that. And scripting is pretty important because I need to be very clear in writing as to what I need to do before I actually start recording. And that helps me a lot in saving time. Some people just write the outline. That is also fine. But I try to make it more elaborate, especially in the intro and the outro. Whereas in the middle part where I'm doing a screencast, I kind of, you know, leave it to the outline. Then the screen recording part comes, as I said, the face recording is mainly for the beginning and the end part of the video where I'm talking to the camera. And then the editing part, which is usually the most time consuming part. And the post production, which is now becoming more and more time consuming. And the marketing part, which is basically tweeting on social media and things like that. How do you know these skills? Preparing a video requires a knowledge of a number of skills. And it's not very easy. It took me a very long time to pick it up. But I found, you know, Skillshare and YouTube to be very good resources for these things. How do you structure and script it? Now, my principle is keep them engaged almost all the time. And the way I engage them is by having a very interesting structure. I start by talking about the problem and I give them clues and I stop it at that.  And this has been very effective. Many people like this approach. And finally I show them how I solve it in my own way. And in the end, I sometimes add a bonus content. Now, what I want to talk about visual storytelling is if you're trying to use video as the medium, make sure that you make good complete advantage of it. For example, some people think that you just have to narrate something on looking at the screen.  All these are good approaches for certain things. But if you want to make them engage like I talked about in the fog model, you have to make full use of the medium. You know, make use of the sound, the sound effects, the music, the videos, the animation. If you can animate a concept, try to animate that. If you can try to explain it using, you know, actual props in the video, try to use the props. Make use of the medium. And of course, find novelty. One thing I have to remember, people who read a blog post have... Thanks, Abhi. People who read have much more attention span than people who watch videos. So try to keep it interesting, try to mix things up a bit. Don't keep it too static and boring. Some of the tools and technologies I've used are, as you know, you cannot simply do a screencast as I used to do in my early days. I would say you can start simple. You don't have to use everything that I talk about. But just to give you an idea, these are the hardware and software I use. When you look at the hardware, you'll find that I use an SLR camera, which gives tremendous video output. And if you can afford it, please use it. Otherwise, even a normal mobile camera or a webcam would do. Invest in a good mic. This is one of the most important things. Your audio quality is going to determine how well people would listen to your content. I actually use two mics, a USB Yeti mic and a Boya Lavalia mic. And lighting is equally important. If your lighting is bad, your image quality suffers. Sometimes you spend a lot of money on lighting. I don't think you need to spend a lot with LED and other forms of lighting, but please make sure that it's well lit. Software I use is almost all open source. OBS Studio is excellent for recording. KDN Live is very user friendly for video editing. Inkscape, GIMP, Blender for image editing. IP Cam is an Android app which can help you use your Android phone as a webcam. And this is how I reach the audience using red, posting it on Reddit, Hacker News, Twitter, etc. This is what I feel what went right and what did not go so well in the project. I felt that showing my mistakes instead of editing them out was a very good decision because a lot of people struggle when they face an error message or find something which went wrong. And I also showed that I also made mistakes and that helped a lot of people to find out, okay, this is how you go about the process of debugging, which I feel is a very important part of programming. Find a niche. So ray tracing was a niche when it started, but fortunately for me, NVIDIA came out with their ray tracing graphics cards and it became like a big buzzword, like what is ray tracing and then Minecraft was created using ray tracing and things like that. So instead of trying to go behind the trends like machine learning or some other hot topic right now, try to find a niche that is more interesting for you and go for it. Yeah, I spend a lot of time between each episodes, even though I had a day job, I feel I could have made it much more faster. And a lot of people did not really use the bonus content, so I felt it was not very useful. Now, what is the one takeaway that I would like to tell you is try to make your own content, try to explain something if you're trying to learn a concept. And I feel that that is the best way to learn something as well for you as well as for the other person who's listening. It might be a better way for them to understand a topic because even if there are a lot of tutorials or content out there, your content might be something that they could relate to, they could understand better. So that is one takeaway. If from the entire presentation I could let you go with, like if you can explain something, please make time to explain that, publish a video, publish a blog post or write a book. I mean, however you want to do it. So that was my talk. Any questions? Thank you so much, Arun. I mean, I expected this and they are known for good sessions, so there are no surprises there. We do have some questions. The first question, one of the questions is, any thoughts on using might be threading to make the ray tracer faster and optimized or using the GPU, which if you already mentioned that. I do cover that in my technique. In fact, instead of multi-threading, I use multi-processing and I give a very good reason for that in the last part of the ray tracer. GPU is something that I have not really tried. In case there is a future part to it, I might try doing that. But yeah, multi-threading is something that I definitely cover in the last part. Okay. And there was one question about the internals of Python. Where can we get the sources for that? So one thing is the documentation we have mentioned, but is there something that you would recommend? See, internals of Python is something that is great if you want to understand why certain things work in a certain way. When I was like two or three years old using Python, I just opened the source code of Python and tried to learn from that. And I feel that is still possible, that is still good. It's one of the well-documented projects written in C. And because I was also interested in how languages work, that really helped. So I would recommend doing that. And there are a lot of good books also about internals of Python these days. There is also a very good book called Elegant Python, which I suggest in case you are learning more about how the language itself works. Elegant Python noted. Yeah. So all of these, whatever you've mentioned and whatever we've spoken about in the chat, et cetera, will be made more tough and we'll be putting it upon Zulip as well.  Again, no surprises there, but thank you Abhijith. And to people who have missed it or have joined late, this will be made available later on YouTube. And Arun, am I right in assuming that you'll be available on Zulip for a while to answer any questions on the Chennai stage? Yeah, definitely, I'll be there. Okay, thank you. I think we are on schedule now for the next talk, but a quick word from our sponsors and then we'll be moving on to Sonam. First, we'll do a sound check from Sonam. Arun, I'm going to bring you down from the stage, but thank you once more. And we will be providing everything, all the resources that Arun has shared and the connect with me details on the Zulip chat and on the Hopin chat as well. Vikas, can you please note that down over on the Hopin chat? Yeah, and today Vikas is helping me out with the Python India Chennai stage. So thank you Vikas. Yeah, I think thanks to the audience as well. Next, Arun, I'm going to bring you down. Okay, thank you.


Hi, I'm Murray Hebert from the Southeast Asia program. It's here at CSIS. Our guest today is Vice Admiral Manson Brown. We're delighted you joined us. My pleasure, Murray. I'd like to ask you a little bit about the role of the Coast Guard in Asia, particularly in Southeast Asia, and if you could tell us a little bit about which countries you're most active in. Well, we're the lead federal agency in the maritime environment for the United States. And so wherever there are ships under the US flag or mariners that are licensed in the US, we follow those interests throughout Asia. The bumper sticker that we use is that we protect people from the sea, we protect the nation from threats delivered by the sea, and we protect the sea itself. So we do that throughout Asia in partnership with the international community and as an expression of our own national interests. So why is the Asia Pacific important to the Coast Guard and to the American people, you might add also? Well, it is important to the American people, as you know, much of the commerce, over 90% of the commerce to America arrives by sea. And so a lot of our trading partners are in Asia, particularly China and Japan. And so we secure those marine highways. We make sure that good things come into the nation from the sea and we ensure that the bad things are kept up. Tell us a little bit about some of the specific activities that you do. I know you help with capacity building in other countries. You work to prevent piracy. You do disaster relief and protect fisheries and many other things. But if you could give us a little overview and be helpful. Well, all of the nations in the Pacific community are interested in the same things, maritime safety, security and environmental stewardship. So as we express our authorities throughout the Pacific, we sort of have become a big brother to some of the smaller nations. And so we teach them. I'll give you a good example. Several years ago, we launched an initiative in Oceana that we consider and we call the fight for fish. We found that much of the U.S. exclusive economic zone is located in the Pacific. And as a matter of fact, 85% of U.S. exclusive economic zone is located in the Pacific. As we're expressing our interest over the sovereign territory there, we are also protecting the fish. And as we enforce fisheries in the area, we were finding that the fish know no boundaries. They would migrate to other zones, smaller nations, EEZs, and they would be overfished there. So the fight for fish is about partnership. We've signed shipwriter agreements with eight nations in Oceana because our sensors are broad enough to detect illegal fishing in their area. We can help them with detection, surveillance, and even take down of the illegal fishers. Wow. It's interesting. What about you also involved in capacity building? We are also involved in capacity building. Again, as we express our authorities, people want to learn from us. They want to learn about how we use ships and aircraft and how we process information, how we share information with the maritime community. And so there's a pretty strong demand signal on Coast Guard capability. And we generally express that through the combatant commanders. In my case, in the Pacific, that would be U.S. Pacific Command, Admiral Willard. And he engages us through his theater security cooperation program, where we will send U.S. Coast Guard maritime training teams to other countries to teach them about the things that they need to do the things that we do. One of the international principles that many countries have adopted is the UN Convention on the Law of the Sea, the UNCLOS. The U.S. has not passed UNCLOS, the Senate has not. If it were to do that, how would the United States and how would the Coast Guard benefit from us? Well, as you know, the President has taken a strong position on the ratification of the law of the sea. As Secretary Napolitano and Admiral Pap, as Admiral Pap says it, ratification of the law of the sea convention really shows the international community that we're serious. Right now we embrace the tenets of the law of the sea convention as customary. But because we're one of the few nations that have not ratified it, there is some legitimacy that we gain from ratifying it. And as we influence other nations to be good actors in the maritime environment, that just helps us with our credibility with them. That's part A. Part B, my area also encompasses the Arctic and the vicinity of Alaska. As other nations are staking out their economic claims under the law of the sea convention, we're silent because we have not formally ratified the convention. So this really helps the expression of U.S. interests, particularly with the resources that are anticipated up in the continental shelf off of Alaska. Vice Admiral Brown, thank you very much. Thank you, Murray.


Next question is from Tehrita 11. If you've taken growth hormones or steroids in years past, do they still have an effect on your current muscle growth? Sure. Yes and no. So here's why yes, right? So muscle memory is a very real thing. So what that means is, let's say it takes you a year of good consistent resistance training and diet to gain, let's say 15 pounds of lean body mass and then you lose it the following year, you'll gain it back in a month or two, right? So it takes you a year to gain it the first time, but to gain it back, it only took a couple months. This is well documented. So if you take anabolic steroids, you can build more muscle and move past certain genetic limits. And then you go off to steroids, that muscle memory remains and you'll probably be able to build more muscle than if you never did those things in the first place. Now here's why the no. So I said yes and no. Here's the no part. And studies now show this. Men who use anabolic steroids in their youth oftentimes have impacted natural testosterone levels throughout their entire lives. Oftentimes it shows up in their 40s. So they'll use anabolic steroids in their 20s and then they'll go back to being natural and it takes three, four months to get their body to kind of regulate and go back and then their testosterone levels seem to be normal and then they have 40 and it's lower than it had been had they never done that. So they have the muscle memory but now they have the hormones working against them because now they have low testosterone. And there again, there's studies that show this that anabolic hormone results oftentimes in lower natural testosterone levels later in life. So muscle memory positive, natural hormone that levels negative. And what you'll find is people who use anabolic steroids in their youth oftentimes have to go on hormone replacement therapy later on in their life. So it's not as easy as people think. I think it's a bit of a trade-off and if you add those two factors up, I guess the answer is it depends. It depends on which one's more effective. Wouldn't it also factor like how much you were using back then and for how long and all that, depending on like how severe it's gonna impact you later on with that scenario? Yeah, definitely. I mean, if you use it for a year on and off, it's gonna have more of a negative impact later on than if you did it just for three months. So yeah, of course. But again, it's funny because there was one study in particular where it showed even doing a single common cycle of let's say 14 weeks or 12 weeks, they showed in the study to have a negative effect on testosterone levels later on in somebody. So which one of those is more impactful on you? I think it's more than that too. I think there's a negative psychological effect also. You take steroids for a couple of years consistently or even a year consistently and get used to what it feels like to train and eat on those. And then that was one of the hardest things for me coming off of steroids would be the afterwards. What after I come off is not feeling as strong, not having as much energy, not being able to eat a little bit out of bounds on your diet and it's still pack on muscle. And boy, that has a psychological effect. If you're used to grabbing the 120 pound dumbbells and now you're only grabbing the 90s, it's a harder to kind of get up for it in the morning to train like that consistently. I have great workouts versus now my workouts will be harder. So even though there might be some physiological benefits that are leftover from it, there's also some negative psychological benefits from taking it before and then not having it that can be detrimental too. In my experience, again, all these things matter. I think people just look at one factor and think, yeah, you're gonna have more muscle later because of muscle memory and that's shown and all that. But they don't consider all the other factors in the context. Look at my experience and I've known a lot of people obviously in the fitness space and I know a lot of people who've used anabolic steroids in their youth for relatively long periods of time. The most muscular fit 40, 50 year old people I know, if I had to compare the two categories of people who used steroids and went off versus people that were always natural, the natural people, the natural people tend to do better. I think it's because they develop better habits.  Their testosterone hormone levels stay optimized for much longer. The people I know who used anabolic steroids in their youth and then went off and never went back on hormone replacement therapy, they tend to not do so well. Now there's also of course the category of guys who then go on hormone replacement therapy, which is a whole another conversation. So if you're listening to this or you're watching this and you're thinking, you know, I'm gonna do it to get the muscle memory effects that way later I could rebuild the muscle. You are not considering the whole context of the effects it's gonna have on your physical body and also on your psyche. And I think if you're doing it once or twice or doing it for a year to give you better muscle later on, it's probably not gonna work that way.  Make sure you subscribe and check it out.


Welcome to the session, High Strength Concrete, myself, Mr. Chetan G. Kunapure, assistant professor, Department of Civil Engineering, Valchin Institute of Technology, Sulapur. So, these are the loading outcomes at the end of this session. The student will be, will understand the concept of high strength concrete, classification of high strength concrete, and methods of making high strength concrete. Now, the concrete which is having compressive strength more than 55 Newton per mm square, that concrete is known as high strength concrete. The strength of, compressive strength of the concrete if it is less than 55, then it is termed as normal and standard grade concrete. And actually, the range of the compressive strength, if it is in between 55 to 100, then that concrete can be called as high strength concrete. Now, in case of this high strength concrete, the major first aspect is low water cement ratio or low water binder ratio. And the second aspect of this high strength concrete is minimum widths. Actually, widths are the sources from where the bond of the cement matrix and aggregate fails and the strength will reduce. So, widths and the strength of that bond between aggregate and cement matrix that is important. So, these two are very important aspect. Now, how we can assure the minimum widths in the concrete? So, minimum widths in the concrete that will make the concrete as a high strength concrete. So, proper particle packing will assure the high strength of the concrete. Now, let us see the schematic diagram. Now, these are aggregate particles. And the void between among all these aggregate particles, these are filled by matrix, cement and mortar. Now, let us see how these voids are filled and what will be the effect of these voids on the strength. Now, this aggregate particle, these four aggregate particles are in contact to each other. This is the enlarged diagram of this aggregate. Now, the macro filler of voids of these aggregates are nothing but the sand particles. And the micro fillers are nothing but the cement particles or cement paste which is in between the sand particles. So, this is entire structure, it may be micro level or at macro level, the structure of cement matrix and aggregates. So, whatever load or stresses are transferred from aggregate to aggregate that depends upon this void. And this void must be filled by sand particles and cement particles. Since macro level fillers are required, micro level fillers are also required. Now, let us see what is ideal high strength concrete. If that concrete in which the appropriate cement type is used in which low C3A, MGO, Freeline, low N, NA2O and K2O components are kept. If that type of cement is used, probably it must give us resistance to weathering and chemicals, resistance to wear and deterioration. It must give us high performance means high strength as well as other properties and it must be economic also. Then that concrete can be termed as ideal high strength concrete. Now, let us see the classification of high strength concrete. Generally, it is classified normal strength concrete and high strength concrete. Now, the compressive strength if it is in between 20 to 30, then that is called as normal strength concrete. And from 30 to 55, the concrete is called as standard grade concrete. This is given in IS 456. Now, high strength concrete is the concrete which is having the compressive strength more than 55. So, the boundary line between normal strength concrete and high strength concrete is 55 MPa. Internationally, the strength of concrete if it is more than 60 MPa, then that concrete is called as high strength concrete. Now, even one term is there ultra high strength concrete. If the strength of the concrete is more than 100 and 100 to 200 MPa, then that concrete is termed as ultra high strength concrete. Now, generally, these high strength concretes are used for high rise buildings and long span bridges. Now, let us see how the concept of high strength concrete arises. What is the cause behind that? In case of pre-stress concrete, the minimum grade of concrete required is M35. So, from the different conceptual point of view, this M35 grade of concrete is required. Now, whenever a pre-stress concrete is to be done, then minimum grade of concrete shall be M35. So, wherever when the pre-stress concrete technology started, then this has given the rise to the high strength concrete. Now, these are the some of the examples. Now, why do we need high strength concrete? What is the need of this high strength concrete? You just pause the video and write down the parameters why high strength concrete is required. These are the reasons. First is if we want early age strength for the concrete, we need this high strength concrete. Especially, this is in pavement because pavement are opened at the third day. So, at the third day, we need higher strength. So, for that purpose, high strength concrete is required. Next is by using high strength concrete, we can reduce the section sizes. The section sizes, especially column sizes, we can reduce so that we can get more carpet area in the building. So, in multi-storied buildings, the column section can be reduced. Next, in case of large span structures, especially long span bridges, high strength concrete is used to reduce the section sizes. Sometimes, if enhanced mechanical properties are required, means in hardened state, if compressor strength, higher compressor strength is required, flexural strength is required, higher modulus elastic is required, then we need this high strength concrete. For some applications also, special applications, especially dams, garages and parking floors, industrial floorings, high strength concrete is required. Now, let us see what are the methods of making high strength concrete. Now, some methods are listed here. Let us see one by one what are the methods. Now, first is seeding. Seeding means a fully hydrated cement, which is finally ground, is added into the fresh concrete mix. The mechanism of addition of this hydrated Portland cement to the fresh concrete is a little difficult. The seeding method is not a promising method to give the high strength concrete, but this is one of the method which is used for high strength concrete. Now, second is re-vibration. Now, concrete means this is a cement product. So, shrinkage cracks are appearing on the concrete surface, especially on the surfaces, micro hair cracks are appearing. These are plastic shrinkage cracks. These cracks may propagate in future also. The mixing water is added into the concrete which creates the capillary channels. Sometimes the water cement slurry is separating from the concrete matrix. In that case also, bleeding is the term which is used for that separation. At some spaces on the concrete surfaces, on concrete volumes, water may accumulate. And all these issues, these three issues will reduce the strength of concrete. Now, how we can rectify these issues? So, we can give the controlled re-vibration to the concrete which will reduce all these defects, will increase the strength. Now, next is use of admixtures. Nowadays, chemical admixtures are coming, model chemical admixtures are coming. In which water reducing agents are helping us to reduce the water cement ratio of the concrete. Now, next is high speed slurry mixing. Now, this involves the proper mixing of cement and water. This cement water paste that is added into the aggregate to produce the concrete. Means all the aggregate cement, water, sand is mixed at one time in conventional concrete. That is a little bit neglected here. Cement water paste which is added into the aggregate with the proper manner, which will increase the hydration process of that cement and which will give us the higher strength. Now, next is the concrete is the brittle material. So, the cracks in the concrete are forming and propagating also. Whatever may be the reason, it may be plastic shrinkage cracks or other cracks. So, formation and propagation of the crack that is definite in the concrete. And the main failure of the concrete is due to these cracks. So, how we can inhibit these cracks? If inhibition of the cracks will reduce failure of the concrete at those weak locations. So, which will increase the strength. Now, this can be done by using or by adding polythene or polystrene. And this is used as a substitute to the fine aggregate and it can be substituted up to 2-3%. So, this polythene and polystrene what this will do? This will arrest the cracks which are already formed and this will reduce or this will prevent the propagation of the cracks. Automatically, the strength of the concrete will increase. By this method, water concrete is welded that is of 105 mega Pascal. These are the references for the high strength concrete session. Thank you.