All right, I think I know everybody here, but I'll still introduce myself anyway for those watching on delay. I'm Mel Hauser, I use she, they pronouns and I'm executive director here at Albrains Belong, Vermont. And welcome to Brain Club. We're very excited for, we're excited for all of our Brain Clubs, but I'm particularly excited because we're joined by some community panelists to lend some other perspectives on our topic. So today we will be talking about re-imagining education. All month long, we're talking about life re-imagined and this is yet another domain of things that we can re-imagine. So by way of introduction, I always like to review this, whether it's your first Brain Club or not, all forms of participation are okay here. You can have your video on or off, and even if it's on, we do not expect anything of you. Don't need to look at the camera, move, stem, eat, fidget, whatever. And you can communicate however, however is most comfortable for you on muting, typing in the chat box, mixing and matching. And in addition to affirming all aspects of identity, one of the other things that we do to protect one another's access needs, that we, I don't know why this is a duplicate. I don't know why this is a duplicate at all, but things that are not on this slide are that we create a climate of just discretion so that people of all ages can participate. And so just keeping in mind that we may have little years listening in terms of language and topics and all the things. And one more bit of access need, housekeeping is that closed captioning is enabled. We just need you to toggle it on if you'd like to use it. So depending on your version of Zoom, either the live transcript CC, or if you don't see that, the more dot, dot, dot and choose show subtitles or hide subtitles if you'd like to turn it off. All right, a couple more news pieces before we head into our topic. Tomorrow, even though it says Thursday, just notice this for the first time, this has been all over social media without realizing that it's the wrong day. Wednesday, January 18th. Tomorrow is our monthly Youth and Family Lunch and Learn series. Tomorrow we'll be talking about kids, video games and extra framing to unlock more peace. And this gets recorded if you can't make it live. And so actually if one of our ABB staff members can put the link in the chat for registration, if you're interested in that, that'd be awesome. And then lastly, last but not least, we are two weeks away from the conclusion of our reimagining what's possible campaign. This is, if you're new to this, this is we have an opportunity because of a generous donation from one of our community members, match $25,000. So as soon as it becomes $25,000, it will become $50,000, which is just unthinkably magical. So this is how we're able to offer all of our community social programming that no cost to participants. And so if you're able to help us spread the word, that is super, super impactful. So thank you for helping us spread the word. All right, tonight, reimagining education. We're gonna do some like just some background about what's not working in 2023. Does 22,000 become 44,000? Yes, yes, it does. So we're already there. Thank you, David, for the question. Sarah Wilkins, our community programs coordinator who is also the lead advocate for the state of Vermont for Lives in the Balance, which we'll talk more about, who will introduce us to the Collaborative Proactive Solutions model. And we'll introduce our panelists. We've got three educators who will be sharing their perspectives on how they see the world. And we'll have lots of time because I know there's several other educators in the audience tonight. And we look forward to hearing from everyone. Lots of time for discussion tonight. So this quote from Alfie Kohn. Any time educators or parents frame the issue in terms of the need to change a child's behavior, they are unwittingly buying into a larger theory, one that exudes what many of us would argue are the things that really matter. The child's thoughts and feelings, needs, perspectives, motives and values. The behavior is only what's on the surface. And in 2023, many systems are embedded in a paradigm centered around behavioral modification and compliance. And when we think about the ramifications of this, behavior without looking beneath the surface, behavior without looking beneath the surface. We're not only missing an opportunity, but we have many unwanted consequences. In the state of Vermont, 587 kids are secluded or restrained annually. More than 5,500 kids are suspended from school for behavior issues annually. And when you zoom out and look at US statistics, 98,000 kids physically restrained or secluded. This is shocking to me, shocking and appalling to me. So Sarah, I'm gonna stop talking and let you comment on this and introduce us to another paradigm. Sure, so I first learned about Dr. Ross Greene about five years ago when my oldest was about five years old. He's an American clinical psychologist from Harvard and he was trained in behavioral modification and went through the traditional training that a lot of doctors and psychologists and teachers go through. And at some point he just started to notice that the advice that he was being told to give parents wasn't working. So when he was asked kind of what tipped the scales in terms of his approach, that's what really shifted things for him was that he kept saying to parents, just put them in a timeout, like they need to be in a timeout and it wasn't working and the behaviors weren't improving and all it was doing was damaging the relationship. So it was at that point that he started to reevaluate some of his training and look at what was starting to come out about neuroscience and the importance of connection and the importance of relationship and eventually after many years of digging through research and doing his own research developed a model and the model is called collaborative and proactive solutions. And he is based out of Portland, Maine now and he has a board of directors and a nonprofit organization that was created that's called Lives in the Balance. So it's really amazing the work that he's done since that organization was formed with all kinds of kids, with kids that really need a lot of help and also just supporting schools in the state of Maine and supporting families. So all different types of people seeking support for behaviorally challenging kids. But the thing about CPS is that it's a model that's valuable for any age. So it's not just a parenting strategy, it's a method of communication similar to nonviolent communication in terms of being a way to really hear the other party's concerns and put everything out on the table. And Mella is saying that she uses CPS to communicate with her husband. Yeah, it's a really valuable method of communication. And so anyway, I'm gonna start by sort of breaking down the basics. For the full information, I would recommend going to the website which we listed in the chat. Cause he does multiple days of training or weeks of training on this model. So this is gonna be like the really zoomed out buried cursory view of it. The first thing to know that's not in this slide that I'll just say about CPS is that you have to change your lens from one to, of looking at a situation, a person, whether it's a child or another adult, from looking at the other person as, they would do well if they wanted to, to they would do well if they could, but they can't. Something's getting in their way. So there's some lagging skills and there's some unsolved problems here. And that's what CPS does is it starts to break down the behaviorist paradigm of, this kid's just giving me a hard time because they just don't wanna do the thing and pulling away from that view. So the three plans that Dr. Green talks about in terms of explaining the CPS model, plan A is what we're trying to get away from, okay? So plan A is the mainstream model, currenting, many current, you know, parenting quote unquote experts, top down solve the problem unilaterally.  And I'm gonna reward you or I'm gonna punish you accordingly. So that's plan A. So that's how Dr. Green explains that. Plan B is really what CPS is about. In plan B, you're solving the problem collaboratively. So your equal partners in looking at this problem and trying to solve it together. Plan C is just setting the problem aside for now. It doesn't mean that you're dropping that expectation completely. It might just be that you're triaging the situation and there's a lot of problems that need to be solved. And this one we're just gonna put aside for right now. So there's four important themes of plan B. The first is that the emphasis is on the problems and solving them rather than on the behaviors and modifying them. Pretty much speaks for itself. The second one is that the problem solving is collaborative rather than unilateral. So like I said in the last slide, it's something you're doing with the child rather than to them. The third is that problem solving is proactive rather than emerging. This is probably the most important part besides the fact that it's collaborative that it's proactive. So it's not done in the heat of the moment. This is not, there's an explosion and meltdown. Things are getting really hard and I'm gonna solve this problem right now. It's noticing when the problems happen starting to take note of what's happening not just right before the behavior but what's happening a while before the behavior in the bigger context of life. Where is this kid at? Or where is this adult at? And being proactive and having conversations when things are calm and quiet and peaceful. And the fourth is that understanding comes before helping. Indeed, understanding is the most important part of helping. So when you're trying to solve a problem using CPS, the first thing to do is to go to the Lives in the Balance website where there's something called the ALSUP. And the ALSUP is the assessment of lagging skills and unsolved problems. So it's a very well broken down chart to kind of document what are some areas that a child might be struggling in if it's a kiddo or an adult and trying to kind of take down information. And that's where you're gonna start to identify which problems you wanna try to solve now and which ones you're maybe gonna put on hold for right now. So once the ALSUP is completed, then it's time to sit down with the child and to solve some of the most pressing problems or the most pressing problem. So this is the three steps to CPS, the real reader's digest version. So the first step is called the empathy step. So when you're doing the empathy step, you wanna sit down and have a conversation about getting information. So we adults, as Dr. Green likes to say, are theory machines. We like to think that we know exactly why a kid is doing what they're doing and we really have no idea. So in the empathy step, we're getting information from the child's perspective or from the other person's perspective. So this might look like saying something like, I've noticed it's difficult for you to brush your teeth before bed at night. What's up? And after that, the child is gonna share their perspective or the other person's gonna share their perspective and it's really about active listening, summarizing what they tell you and not jumping in with your opinion. So you're really just listening, repeating back what you hear. The second part is to define the problem. So this is where you're saying the same concerns that you would have said in plan A, you would have said, well, you have to brush your teeth because this is why you have to do it. And I'm gonna reward or punish you. But instead of doing it with that kind of energy, when you're defining the problem in CPS, you are stating it in a way that doesn't cause the other person to kind of have that wall go up. So you're collaboratively finding a solution that's gonna work for both parties. So this is where the adult or the person who's bringing up the problem gets to share their perspective. So you might say something like, the thing is I'm concerned if you don't brush your teeth that, da-da-da-da-da, you know, this is where you fill in what your concerns are. Because it's not about letting the other person just get their needs met. This is very similar to what we talk about with all brands belong with access needs, what each party needs in order to meaningfully participate. And so this is the opportunity to kind of have that conversation and talk about what are your access needs? These are my access needs. The third part of the step is the invitation. So this is where you are trying to find a solution that works for both parties. Because if you don't find a solution that works for both parties, the problem is unsolved. So if you come up with a solution and it has nothing to do with what the child's concerns are or the other person's concerns, that's not a solved problem. So you would say something like in this scenario, I wonder if there's a way that we could still make sure that you brush your teeth at night, but also, and this is where you're gonna put your child's concerns in or the other person's concerns. And the idea is that the solution, again, is mutually agreed upon. And then at the end, clarifying with the other person, you know, saying something like, would that work for you? And you can always try on a solution for a while and see how it works and you can come back to it. It's not a definitive like once and done kind of thing. And so, you know, again, this is a real cursory view of CPS, but just to give you a sense for the model, and I would really encourage you to go to the lives in the Balanced website to kind of learn more, but it's really incredible to see how schools that have implemented this model have reduced or eliminated the need for restraint and seclusion. There are schools that were interviewed in Maine where a special educator was saying, we were having, you know, situations daily to the point of needing to call in authorities. And I mean, a really messy situation. And that just really drastically was reduced because of CPS. And it's really about proactively looking at what can be done ahead of time, not in the heat of the moment. And it seems like a lot of steps, it's, you know, it's putting in the time up front though, so that you're not having to put in the time with a really damaged relationship and a kid that really doesn't feel good about themselves or another person that doesn't really feel good about themselves afterwards. Thank you, Sarah. And as soon as I can figure out, there we go, our Zoom motor planning, you know, my least favorite thing. So with that, I'd love to introduce our community panelists. I'll introduce you together. And then, you know, you can tell us how you view the world and then we'll open it up for questions and discussion. So let me just tell them like, I can't talk and figure out Zoom motor planning at the same time, add spotlight. And Anna, where are you? There you go, add spotlight. There we go.  Anyway, so, I was very impressed. Say that again. That was impressive. I've never spotlighted before. I'm very impressed. So Jen Bryant is a special educator at Union Elementary School in Montpelier. Melissa Anderson is also a special educator and social emotional learning teacher at Union Elementary in Montpelier. And Anna Hause is an educator and a family coach in private practice. So, I don't know who wants to go first, but somebody go first. I'd love to hear your thoughts. I can go. Just because I think mine connects, I mean, I'm sure all of us are gonna say things that connect to what Kelly just shared, but part of my, well, most of my job is essentially like a teacher coach this year. My job has looked different every year that I'm at school, but this year it's really exciting because I'm using this CPS type model to train teachers about classroom management. So I go into all the grade level team meetings once a week and share tips and tools for them to implement during the week. And then I also go in and model lessons and model interactions with the children. And the one thing that we're focused on this week, which is something I talked to Mel about, and she said this fits right in with Green Club, was using the lens, if you are looking at behavior, through the Ross Green quote, kids will do well if they can. So looking at a behavior as not a child won't do what you are trying to get them to accomplish, but that they can't because there's some sort of barrier in the way. So the mindset with those two different approaches won't versus can't is on the world side, the mindset is pretty judgmental. You may view the child as willful, defiant, and maybe your thoughts about that child, they're lazy, they want attention, they're doing it to get back at me. And then the response is, you know, traditional rewards and punishment. And then the child ends up in frustration, guilt, shame. So that's not necessarily a productive way to approach when a child is having a hard time.  So when you think about that in the lens of can't, you're more curious. You are looking like a detective. I hold up a magnifying glass sometimes to remind teachers like, get curious. And I say that to myself, get curious, ask questions, try to find out why this child is struggling in that moment. And then your thoughts about the child maybe, how can I help? How can I support? What can I do to help this child get back on track? And the response is that you're finding and removing those barriers for them. And then in the end, it feels better for you as the teacher and it also feels better for the child because they feel supported and strengthened and heard. So that's kind of where I'm at this week and that's a lot to take in. So I do it in little bits so that people are really understanding and practicing and using these methods. And I just have a couple of quick examples and then I can pass it to someone else. But for example, today I was in a kindergarten classroom and they were doing this really fun project and the teacher showed how to do it.   And, you know, we could have continued on that path but I just looked at her and I said one word. Why? Because everything was fine. And she started crying and said, I didn't get a chance to talk. And I said, well, what did you wanna say? And she didn't even know, but then I said, well, what, tell me about your project, what you're gonna do. And she flipped right around. You know, she got right to work, sat down. She just didn't feel heard. And if I hadn't caught that small, no, I mean, it was kind of big but it was just so surprising to me and out of the ordinary instead of saying, no, we're getting up, move along, go to the table. I mean, that's forcing the compliance and not getting to the root of the problem. So I have lots of examples like that that I could share but I don't wanna take up all the time. I'm wondering if I can follow in your steps here because I often do this. I am really fortunate to work with Melissa. And so we often go in and have meetings where I say, close the door. We need to confer for a few minutes. And I often follow her into these classrooms. So this kindergarten classroom, I think I might, was it turkeys that you were working on in this classroom? So I often follow her in and work in her steps. One student, in fact, that I'm assuming she was in there to work with had a really successful time with these turkeys. And it's nice to remind teachers, isn't it great that he had such a good time doing this? He is such a hands-on learner.  And so I think oftentimes teachers need just as much and Mel, you mentioned that you talked to your husband using this same and my kids. And I often also talk to other adults that I think need a little bit of guidance by having this kind of be collaborative problem solving together. My role is often working with students who are needing a little bit more support. So I work with students who are working with a lot of other adults. And so I'm also doing some of what Melissa's doing while also working with the students where I'm talking to adults about, it's not that they don't want to do this, it's possibly that they can't. Like let's find out what that lagging skill is and let's work on that lagging skill. Melissa said something so amazing this morning and I wrote it down, but then one of the paraprofessionals that I work with is feeling really frustrated today. And I said, here's some great reading for you. And I think this is something that would be really helpful and I handed her that paper, but it was that idea that compliance is something that we use in an emergency or when there's danger involved. So when we expect compliance, it should be because it's something dangerous. So the example was putting on snow pants. And what if a student says that they won't put on their snow pants? And you say, well, why? Again, Melissa gave such a great example of this, why?  And if they don't want to, great. There's a logical consequence that follows and we protect our kids from so many risks that they no longer know how to take safe risks. And so this gives them that this time and a safe space to take those little risks and really make that work and learn what works, but also to be part of the problem solving solution. And then lastly, I'll say that I think of some of the students that I work with who have demand avoidance. And oftentimes we call that pathological demand avoidance. There's all sorts of things, but when we think of it as proactive demand avoidance, sometimes they're moving away and now I think I've used that language with you as well because that's just how I look at it. They're moving away from that demand avoidance because it feels dangerous. And when you remove that power struggle from the equation, there's no longer that danger that keeps them from those elements of safety that they look for at school when they look for that safety connection and regulation are like those three key things that we need before students are accessing their education at all. So removing that power struggle, removing that demand and making this a collaborative case for each student allows you to get to know the student, allows them to get to trust you and really allows them to learn overall. I talked for a really long time. Sorry, go. I'm gonna pass to the next person. Thank you. I think this worked perfectly because I totally want to pick up right where you left off. And I'm also so passionate about this. It'll be hard to only talk for five minutes, but I wouldn't do like this. So I wanted to start with just like what changed my perspective about this because I was a student who didn't get gold stars. I was a student who like rewards and punishments never really worked for me. I ran under the radar quite a bit, but when I became an educator and I was in college to learn to be a teacher and I was so passionate about it. And I was then learning these same models that didn't work for me as a child. It was interesting to feel what it felt like to have to replicate these systems in order to graduate college. Like I had to create rewards charts and I had to create systems where tables got points for doing good things. And the tables that didn't get the points didn't get the ice cream and all these things. And I thought about how it made me feel as a child. And then I really took in how it made me feel as an adult. Like it didn't feel good. I wasn't creating that relationship. And I picking up on the thread in the chat, like there wasn't a priority on building a relationship with my students. And that was really frustrating. And I became a parent really early as a young parent kind of simultaneously as going through college. And then it was the same thing. Like I was using a lot of these ideas of consequences. And I'd watched one of Ross Green's quick videos on YouTube about consequences. And this is where you were kind of talking about that a little bit, Jen. Like the difference between adult imposed consequences as opposed to natural consequences and things that occur naturally. And so from there I created this model that's a little bit more scientific. It's like let's experiment together and see what the consequences are because we forget that actually there's a lot of really positive consequences to things that we do. Consequences don't just mean bad things or punishments. And so that was how I started to shift my language because I was using a lot of language around consequences and taking away privileges. And I was able to start to shift as I became a scientist, like discovering things alongside my child and like creating that kind of cooperative experience. And from there as an educator I actually developed an after school program that was a democratic cooperative classroom in which the kids came specifically I held the space as a teacher specifically in mind with how do I get the students to collaborate on deciding what they learn and how we learn it and what's available and how we meet each other's needs. And then along came my daughter and punishments and rewards just don't work for her even in the slightest, you know it was she has such a great way of being so clear about her need for autonomy and definitely has that demand avoidant nature and it was a huge eye opener for me. So I wanted to give just two examples. One is one of the things I really like is this idea of being proactive instead of being like emergent having to be like in the moment and then be like, ah, now we have to do something about this but how do you be proactive about it? My first example is actually an emergent example but I leaned on a lot of these tools to support this family. So I was bike riding with a family and, you know, there wasn't a discussion about where we were gonna go but clearly this family took bike rides a lot and it was my first time out on these trails and we got to a fork in the trail and the father said, oh, we're gonna take a right, let's go this way. And the four-year-old was destroyed. I mean, he just lost his mind. He was so upset, he couldn't even speak and the father was just like, get on your bike, let's go. I said we're taking a right and he just started, he just started riding away and he told all the other adults, you just have to leave him there and he'll start following us. And then this kid proceeded to get on his bike and ride while sobbing and crying and screaming, riding his bike and riding his bike and this probably lasted for five minutes before the father's turned to me and said, well, do you have an idea of what we could do about this? And I was like, I would do actually. And so we were able to define the problem as adults while the child didn't even wanna get close to us. He was still sobbing on his bike and he had stopped a little ways away from us and finally the father said, I really wanted to show you the river. That's why we're going this way that I have no idea why he's so upset. He clearly wanted to go take a left and he said, but I can't just let him have his way. Like that wouldn't, we can't do that. Then I'd just be reinforcing all of this bad behavior. And so I encouraged him to do this thing, take a deep breath, take a moment, actually ask his child why he's so upset. What was it in that moment of taking a right that made him flip his lid, got him so upset? And I said, and then from there, focus on the compromise. Focus on how both of your needs can be met. And I didn't actually get to hear the conversation because they kind of went and did their own thing, but I watched as the nervous system started to settle. I watched as they began to connect and they came back and this four-year-old was beaming and he said, my dad wanted to show you the river, but I really thought we were going to the playground and I really want to go to the playground. And we can, there's a place where we can see the river on the trail, on the way to the playground. So they like, they presented this compromise. It was so beautiful to see that the father's need of seeing the river, showing me the river and the child's need of going to the playground could both be met. And we turned around and we went to the left and we went back to the playground and we stopped and we looked at the river along the way. And actually I'm remembering when I told Sarah I was going to tell this story. I wrote a song with the child when we got to the playground and I was going to look it up. So I recorded it as a voice memo and I had forgotten about it, but I like to do that with children to like make songs to help them express their feelings and to help things kind of sink in. And we made a song and the lyrics were something like, we can do it together. The lyrics to the song were kind of repeating over and over again, we can do it together. You and me and we can both basically be happy and we can do it together. And it was like so elated. So I'm not able to keep up with the chat while I'm talking, but there was so much great things going on there. And I just want to emphasize this piece on, emphasizing that the relationship takes priority or that outcome. And that's one of the things that's been so important to me even as I sit with my students or my children or support parents in being with their kids that it's not, you don't go into this process and it's a three step process. It's not that complicated. It's like, hear what they have to say, speak what, what your concerns are and then work together to create a solution. And the most important thing is as the adult to not go into that kind of conversation already with an expectation of what the outcome is going to be because that will be at a detriment to the relationship in that moment. And you may not get, and the first conversation to something that's perfectly satisfying for you as an adult, right?   Oh, sorry.  Like, can you still be there? Can you carry the snow pants outside? You know, that's not always possible as an educator but like, can you be there to be that supportive person so that when they do get wet and the inevitable happens that you knew was gonna happen, they're gonna be upset and cold. You can still be there as that settled nervous system to support them through learning that in real time. And yeah, can I just step in for a minute? You said something about not expecting the outcome. I think equally important is not expecting or assuming you know what the problem is. Yes. Because I always have an idea and then when I dig deeper, it has nothing to do with what I thought it was. So, you know, I think equally, just not assuming that, you know, you can figure that out. Oh, thank you. Yes, sometimes it's I'm hungry and they finally say, I didn't eat breakfast in the entire time you're trying to solve all of these problems. And sometimes the other part of it is maybe not trying to solve all of the problems because sometimes those problems don't need to be solved. And I wanna add in, because this gets a lot of adults hung up is that when a child acts out, we take it really personally. And when we start to take it personally, it's a lot easier to start making assumptions. And I saw that a little bit in the chat, right? This assumption that teachers will make like, well, they're just trying to get their way or they're, you know, there's like, that's often because it's touched something in us that, and we're starting to take this personally and being able to say like, actually what the child is experiencing, the struggle that they're experiencing has nothing to do with me. This is about them. And the only way I'm gonna know what the problem is is really by attuning to them and asking them. And so I have created a five module online course that really supports people in going through a lot more detailed steps, right? We've got the three steps that's really helpful, but all this stuff that we're starting to say around not making an assumptions and not taking it personally. And like it takes a lot more skills. And I really appreciated, Melissa, that you talked about practicing this, like it takes a lot of practice. And so my course takes parents through five modules. It starts with slowing down. And the second module is titled building trust. The third module is called create connection. And each one of these builds in games you can play and exercises you can do for yourself and different concepts to think about, especially this thing around being a scientist. I like to do that a lot, making observations, having a hypothesis, trying something out. If it doesn't work, that's okay. You've just discovered that your hypothesis was wrong. So you just have to make a new hypothesis. It's not a big deal. And you try it again. That's what scientists do all the time. And then the last two modules are titled independence and success. So module four focuses on routines in everyday living and module five focuses on positive outcomes and around this piece around really being co-creative in finding positive solutions with your child. So thanks for listening, everybody. Thank you, Anna. And there's a request in the chat if you could throw. I put the link to your website, but if you have a specific link to modules or course, et cetera, as direct link, that would be amazing. And then a question in the chat opened up to the whole panel. It looks like Jen has some ideas about language to use to name how, why it appears that accommodations or dropping of the demand is being done for some students in a classroom. I think the really big thing to point out here is that often it is not the kids that are feeling this way. It's the other adults. Kids really get it. They're noticing that kids need different things.  And they say, I have a caught on my knee. And so you hand them the Band-Aid and say put this on your knee.  Where was your boo-boo? What happened? Where did it hurt?  Well, here's a Band-Aid, put it on your knee.  Okay, here's a Band-Aid, put it on your knee. And they start to say, well, why am I putting it on my knee? I hurt my elbow. I don't want it on my knee. And it just opens the discussion for why everybody needs something a little bit different. And I really think that's magical. There are so many others that it could take all day to go through how many different ways. But really I think that in general, kids just get it. I love that. I, and I think you're so right.  And we talk so much about unsolved problems when we're talking about this. And I think as adults, we look for problems and we feel like it's our job to solve them. And so we're looking at these things from this lens of, what if this is a problem for these other students? How do we solve this? And sometimes it's not our jobs to solve it. It's our jobs to just sit back and listen and to observe. And again, as both of you have said, to be a scientist and see what's happening. Other questions or comments from anyone in the audience? Do you hand, but then disappeared? I've turned on my mute, off my mute, I don't know. Oh, go for it. Great. I have struggled so many years with just the realm of education, like as a parent, as a student, as a professional in the district. And we ended up pulling our child from school because he just, he didn't feel safe. And he told us that in multiple different ways. And now we homeschool and we moved out of the district to boot. We're like, you're homeschooling and we're leaving. They will never, ever harm you again. We felt we had to leave to help him feel safe. After a year of homeschooling and his brother going to the new school and kind of given us feedback, he decided he wanted to try a couple of classes. And so he goes to science and recess and art. And we actually just had a team check-in meeting today of which he's invited to, which never happened in the old district.  This will be boring for him. And we're like, oh yeah, talking about himself. That's not the worst thing ever. But he participates now. And he was so, he was able to say, I don't know if I can trust you yet. I don't know if you're lying to me or not. And it was so huge. And like got wrenching at the same time because I truly didn't understand the depth of how much he mistrusted school adults based on these well-meaning, good intentioned, one-size-fits-all strategies. When you're talking about compliance being needed for safety, he was subjected to compliance tests after meltdowns. So he had to go around and apologize to anybody that he might have upset. And we didn't know that, obviously. We never would have approved of that. That's cruel. Nobody could do that. And I shared that with his new team today and they were just so floored. And I was like, this is why he's starting to trust you because that never would have even occurred to you. And they were like, why would it occur to anybody? Just like, I don't know. I don't know. And something else was said about how hard you have to work with somebody else our fourth grade teacher used to comment, oh, he had a hard day or he had an easy day. And finally I called her out on it. And I was like, does that mean that, well, he had a hard day. And I was like, oh, does that mean that you had to work harder? Because that's what I'm hearing. That means that he needed more supports. Not that he had a hard day. He needed more supports today than he did yesterday. And that's okay that that happened. And it's just, I'm so happy that there's more understanding behind the behavior and more work and effort being put into kids are no longer just seen and not heard. We're finally listening. And I think that's the important part is we're finally listening to the kids saying, hey, I don't know if I can trust you or not. Right, right. And only the kid gets to decide when they feel safe. Right. Thank you, Kelly. Thank you for sharing that. Laura. Thanks everybody. These were really great presentations today. I have a question. We had an issue recently in our house where we had a collaborative plan related to getting some vaccines. And when we got there, the plan went out the window and it didn't go so well overall. I'm not really happy with how any of us responded in the moment, but we've had a lot of conversations since then about bodily autonomy and who gets responsibility for making choices about our bodies. And I'm wondering how you reconcile that with decisions that you are making about health and how to balance those things where you are giving power and you are giving decision-making and autonomy, but you're also making things safe. Totally. So I can speak to that one. This is, CPS can work so well for topics like this. Sarah gave the example of brushing teeth in my example today in my house because my husband has COVID. He's like isolated in our room, never to come out for 10 days. But I want Luna to be like stuffing up her mass cell an anti-inflammatory game to protect her immune system. And she is not having it. Why? Because I want her to take these things. PDA, right? So naming the thing of I am noticing that the more I want you to do the thing, you cannot do the thing. It's not a will not. It's a cannot, they cannot accept this. It does not feel safe because my energy is all about power over. I'll name the thing, but so, but I try to explain to her why I am energetically pushing my agenda. I am worried about this. It is important to me about this because I love you. Let me know how else you think we can accomplish this. And she's had some ideas about how she wants this to go. And transparently saying like, I believe in bodily autonomy and I love you. And I know that this, that and the other thing is a health thing. And I worry that if not for, anyway, like that's a lot of language. But like as, and again, you have to be, your child has to be, or your other person has to be regulated. Like you have to have access. In my house, we'll literally say like, do I have access to your cortex? Because my cortex and your cortex have to having a conversation. In my house, rarely do two people have access to their cortex at the same time. And that's okay. But like it does not make sense to talk about literally anything if someone does not have access to their cortex. Anna, and then, and I'm reminding myself of Kelly's hand in the corner Go ahead, Anna. Great. I just wanted to give some like quick language here. So this is really the shift between I'm the adult. So therefore you do what I say to I'm the adult and my job is to keep you safe. How can you help me keep you safe? And so it really shifts it away from that power over to that like, let's be collaborative on this together. Like I realized this is feeling really stressful for both of us. So the solution isn't whether or not you're going to do the thing. The solution is how can we do this with the most peace and love? Because that also I'm the adult and therefore my job is to love you. And so how can we do this in a way that makes us both feel loved and supported and safe? And so there's still a lot of autonomy and a lot of choice in that kind of language. And one other thing, Laura, sometimes when in your specific example that you gave when it's really, really hard to follow the plan for something that scary in your child's eyes, sometimes an external reward might be needed in a situation where it's really hard to come up against that. So saying, well, let's do this and then we'll go out for ice creamer. In that case, a reward is appropriate because when this child is having a difficult time accessing the skill, they need that little bump to be able to pull that in. Thank you. Kelly. I had just a quick question for the special educators.  And one thing I come up with or come against a lot is trying to create a safe space for students, children to explore themselves. But when they Google things like autism or neurodivergence, some of the stuff that comes up is extremely harmful and the language that's used. And I think that we live in a world where people still don't even really know when they're using harmful language a lot of the time. And I was just wondering if you had any advice on ways to help students explore and learn about themselves in a more self-directed way while still protecting them. If I could just jump in, I think you can provide them with resources that are neurodiversity affirming and you can teach them the concept of brain rules and world rules. The idea that there are people, and this doesn't have to just be about neurodiversity, this can be about gender, this can be about all kinds of things, that there are people who have some thoughts that are just wrong. That part of the real world is that there are people out there whose thoughts are just wrong and to provide them with resources that are actually helpful. I'm gonna put a link in the chat before I learned I was autistic and was initially developing my monotropic focus on neurodiversity. I dumped a whole bunch of resources on a website, not knowing that not everyone does that with their interests. And it has like a whole bunch of resources, including things that are like noted for kids and teens and stuff like that. But I wonder if anyone else has thoughts about that. I've actually seen your website now. I've used one or two of the resources in the class that we're designing. I don't know, I guess I just feel like I don't wanna censor the world, but I need to censor the world. So it's these two polar wants and needs that are competing all the time. Yeah, yeah, so like even my, I think you just bring transparency. It's not censoring, it's just naming. There are websites out there. You may see this, like I have a teenage patient who after, like actually in the day that I made her diagnosis and was, I played a video as one of the Agony Auti videos about what autism is. I played the video and then I said, let me tell you what you're gonna find when you Google. And named the thing. And she was like, that's ridiculous. I was like, I know. So just like, you're not, you know, you're just like, yeah, there's a lot of bad information on the internet. Let me teach you how to be an educated consumer of the internet. Like it goes so much beyond neurodivergence.   So they can start to be able to filter through information that they're getting. And so I just wanna say like, that's what we're all doing together is like building a space in which children can learn and grow to discern for themselves like what information feels true to them and what doesn't. Because there's gonna continue to be a lot of adults in their life who say, do it because I said so. And they're gonna have their own approach to handling that and they're gonna be more successful when we give them tools like the ability to talk through and come up with collaborative, proactive solutions. That is so well said. We'll probably have time for one more question. Jen. This was so amazing tonight. I can't thank everyone enough for their amazing input. So I'm kind of shifting from the boots on the ground to weigh up at the top of state education departments in helping them understand what neurodiversity looks like in a classroom setting. I am fortunate to have had the experience of being a former Board of Education member and teaching kids as a former special education teacher, gen ed teacher from kindergarten to 12th grade in knowing that this has to go from the bottom to the top and vice versa. And our leaders need to understand that every single classroom needs to have flexibility within teaching content because as we know, developmental skills and content are two very different things. How do we get them to understand all of this so we can make changes of having more support in the classroom, more language support, more people pushing into the classroom so we can give every child what they need and meet their access needs. It's a conversation for another day and something to start thinking about bringing it all the way up to the top to get that change back down. Amen to that. And I think that you come at this from a really important perspective, you are directly bridging the double empathy problem. So because when you come at people and you tell people that they're doing it wrong, they flip their lens, right? So you got to oblique approach it. And so universal design benefits all people. And so that language, I don't know as a, but again, I'm not the person to deliver that because I'm not an educator. And so it's that I think because I don't know. I mean, I'll ask all the educators in this virtual room. Like are there people who in education who think that universal design is not helpful? Like I don't know people like go around and say that's not helpful. Like it's just that, you know, it may not be the thing they're focusing on right now, right? I mean, do I have that, do I have that right? Laura. I find it super, super helpful. I will say it takes me three times as long to create things when I'm trying to implement UDL versus doing it without it. I totally get that. I mean, even to say like Brain Club is not delivered via UDL, like because we don't have that capacity. We are working on, we discussed this at our last community advisory board meeting about creating visual handouts with take home points and that's articulating the main ideas of a given Brain Club in plain language. And so that's gonna be something we're gonna be rolling out in this winter. But it's, and I'm reading from Laura's comment, first year's super hard after that way better.  Oh, cool. All right. So Kelly has shared a link in the chat. I've gotta tell you guys about this link. So this is like the chat GPT, but for educators. So you can put in what you wanna teach and it will auto-populate every, like tons and tons of ideas, how to do it. So it just saves a lot of that brain strain. What I'm gonna do, because the chat is not, it won't come up on the YouTube station. Before we wrap up, I'm gonna share screen and show the screen of this URL so that people can have that.educationcopilot.com. Cool. Well, thank you. Thank you, everyone. Thank you so much to Jen and Melissa and Anna and thank you to you all for being here. And we look forward to seeing you next week for reimagining employment.


I want to talk about our lessons that we learned by building a decentralized application on top of Light Client.  Like, kind of, if you think you know what's like fairly well, what's a Light Client? Okay, it's like half of the person, so I will be a bit slow at the beginning just to make sure we're all on board on why we want to use a Light Client actually. By the way, I will use the words Light Client, Light Node. For me, it's the same because we're talking about a Node. So just two words about myself. I'm Thibault, I'm working at Parity, I'm a front-end dev and I work on Parity Feather, which I will talk about right now. I work also on Parity Siner, which I had to talk about before. Pretty interesting, you should check it out and right now I'm actually working a lot on Polkadot, JS and UI. So this talk is about three things. We want to understand first why we want to build or use Light Clients. Then I will show you how to hack on a library that we made that's called LightJS and then in the end I'll show you a bit more about Feather, this application that we built on top of a Light Client. Here you can see I use Light Node inside an electron app. Light Node, Light Client, same thing. So let's start why Light Clients are important. So first of all, you probably all know but running a full Node is not as simple as it could seem or as simple as we hope it would be when people built a Node in the first place, we thought okay everybody should be able to run a full Node on a laptop, right? Well it's not really possible anymore so what do what people do when you want to build a Light Client or sorry when you want to build a decentralized application you do not connect to a full Node, you connect actually to Infra or to a third-party service that provides you a full Node to access the blockchain and the thing is Infra is super awesome like you can build an application connect to the blockchain within a couple minutes that's really really nice like it helps a ton the community to grow but there are many problems in there yeah those are numbers that I mean actually kind of old numbers is probably much higher now how many DApps have been developed using Infra how many billions of requests Infra is actually serving the problem you can all see that we call these decentralized applications but we're all connecting to one server here like or one set of server that is owned by a company that is not decentralized that's actually not the right thing to do right so what is a Light Client? It's a Node that stores header but will remain trustless so it's a Node so it's something that does access the blockchain and can give you many information about the blockchain can help you do almost anything a full Node would help you do from a decentralized application perspective but it is not decentralized it is sorry decentralized and it is not centralized it is it is just and it does not so it's not as secure as a full Node I will not talk about this in this talk because it's just it gets too complex but it is trustless so you cannot get fake data or something you know it's decentralized and it actually verifies all the requests and all the information that that it gets so just a couple yeah numbers to show the differences between a full Node and a light Node or Light Client the sync time is a couple seconds if you're lucky if you're not so lucky maybe a couple minutes but we're not talking about hours or days right as long as you have internet I'm not talking about this Wi-Fi here because it could be could be minutes or days yeah I tried it I did sync a light Node in the Chinkansen for instance with my 4G right it took a couple minutes but it was it was doing doable the state size so how many gigabytes or whatever are you going to download on your mobile phone or on your PC with a light client it's going to be zero it does not source the state with a full Node of course that's its job it's going to have gigabytes and gigabytes of state and the database that you're going to have again on your on your desktop or on your mobile it's going to be tens of gigabytes people are talking about terabytes I won't go into this debate but anyway for full nodes and like client is we're talking about couple hundreds of megabytes so what is a light client or why do we want to use a light client so today you have on the right the nodes the full nodes that are connected to each other and they form the Ethereum network and you have your decentralized application that is there and sits there and when you want to connect when you connect to say in FURA you connect to one of these nodes or let's say a set of node that is owned by a company and you trusted this person so this person can actually turn bad and what they can do is they cannot change your transactions or something they cannot you know spend your money on your behalf or something that's okay but still they can track you they can exactly who you are with the IP they can see okay this person is using this address all the time like they can do many mean stuff or they can censor you right infrared they are nice we know them and they actually want to get decentralized more they had talks about it I'm just saying this is not the right way to onboard people we all know that okay we want to care about decentralization in the space that's why we want to bring people more people to the space so let's let's do it right and what we can do is so the the new dots here or light cleanse so they are connected to full nodes and what we want to do is actually embed a light client in our app this is what we did and this is what we want actually to let people do more so to let people embed a light client and use a light client in their decentralized application we bought a library that is called like just so it's super light it's for light client everything is light and here's what here's how a stack that you would have today for your normal app so basically you have your UI in JavaScript most probably using React Angular whatever then you embed web 3.js which you want to use to just send transactions and do stuff on the blockchain this web 3.js one of the first thing you do with web 3.js is setting a provider you have new provider and there you most probably use some URL from Infra with a token that you have and then Infra so this centralized service node that you have to trust in this case we'll talk to Ethereum and what we want to do so yeah these guys can eventually censor you or or track you and so what we want to do with this light.js is actually instead of web 3.js you use this light.js and this we'll talk to a light node on your own inside your app actually and you will talk directly to the Ethereum network so the difference here is that you remove right the centralized node and you put the light node actually inside the app right so this light.js library is a high-level reactive and easy to use library we'll talk about it just a bit we are well how do you install it just like any other library you probably saw today it's from the parity name face and slash light.js so let's have a look a bit at some code I hope you can see that all right so that's a really simple sample code so you can see that we import lights and we import balance off and block number and those balance off and block number have a dollar behind and it means they are these are observable and just like you would do with web 3.js today you would just do light set provider with your provider and then you can do with these observables block number you can subscribe for instance and this will give you a block number that you can log and so in this in this little program we'll just subscribe with the block number and just log the current block number and we do kind of the same with balance off so balance off you want to say which address you want to see the balance off and then I don't know if you if you were or if you know how to use reactive or or xjs but basically you can get what's the result of balance off and pipe it and do something with this with this result so what we're gonna do is this balance is gonna be formatted or you have a question so the question is will balance off well be actually a stream and updated and the answer is yes and this is the nice things without observables and you'll see that in a second so the balance off will be you know not formatted nicely so what we want to do is from way we want to format it basically and then what we do is we do the same as before we subscribe to this and we just log it so what happens is when you just run this in the console it will just go like this current block blah blah blah my balance and then it updates and then it updates you change the balance boom the balance will show the new balance and then it updates and it goes on so this is an observable and well yeah that's our xjs like this is not what we built this specifically we just built on top of this and and this is awesome that's why we we use it so like just I said is like it's actually extremely simple we did not go crazy with the amount of things we want to support we actually just support what we need and what the community up to now has told us they need so we have 12 functions and that's it right we have like super basic things the block number you know you can post transaction post road transactions already signed transactions you can get some contract you can get you know like my balance the version info of the node and stuff like this so just to see an overview of the differences between for instance web 3.js and like just so the account management the way it's done no sorry they are asynchronous management with web 3.js you would use promise we use observables the coverage of the RPCs that we that we support we keep it very very simple right and if you need some more please just let us know and of course and this is the very important thing like client like just is built the way we have it in mind is it's built to be used on top of like client and it brings a lot of things that yeah that do not comes embedded in web 3.js and I'll talk about it right now so so behind the scene like just uses the least possible resources on the like line so what you gonna do today just before I showed you okay what's the latest what's the latest header for instance or what's my balance for instance your balance will not change every second right the block number the block time is 15 seconds on the theorem does not make sense to just bother the node you know every second on 500 milliseconds right today you can do that with the theorem but it does not bring anything so light client the light.js library will do this for you right we'll actually get just a push notification will not have pool so you will get the the latest information when it's there not when you ask for it because sometimes developers just don't know everything and that's fine and that's why we wanted to build light.js this way so it fetches states on your head and not whenever you want so it just gives you new information whenever there is new information actually. It handles the subscriptions to the node for you it handles cache and it keeps the amount of network calls to the minimum but to the I mean it's still it's still there's you know you won't be like outdated you won't get outdated information it just does the thing like in an efficient way right so our goal and the reason why we built all of this our goal is to embed light clients everywhere as much as possible and to facilitate a very mass adoption while maintaining decentralization because we do not want to to just trade this off right so because of this we you know probably parity has built a node and this node can be run as a light node as a light client the thing is we wanted to use it and to see how things work and we wanted to embed light let people embed light client everywhere so that's why we built feather so feather is an application on top of a light client and I will show you just I'll show you in a minute I want to just talk very briefly about the stack so just like we said before so we have you act UI in react we use light.js to interact with a light node that is inside an electron app and all this app will interact with directly with the term network without third-party service in between so truly decentralized wallet is what feather is it used to be not the only one because mist used to be also using a light wallet unfortunately it's not possible a light client sorry and for students it's not available anymore due to other reasons so to my knowledge feather is the only application unfortunately on top of a light client so it uses light.js as I said it's bundled with parity of theorem light client and it sinks in a couple minutes depending on the Wi-Fi we have other interesting libraries that you might want to see one of them is called parity electron it's a small library to start and stop parity of theorem from a node.js environment and you will see the UX and everything about feather right now so here I just launched feather and this is what happens at the bottom you will see that it starts sinking right now and it just shows you you know like and shows you the how far you are and shows you an empty page because you have no account so I'm gonna check create a new account this looks like a green cat so I'm gonna name that green cat you know and now it's getting synced you know like at the bottom you can see sometimes so we show the you know the mnemonic blah blah blah you have to be careful with the mnemonic please type the mnemonic again and then you're gonna have the password and just to secure your account and it's sinking in the in the in the background so it's you know it's not extremely fast but it's alright and I can also for instance important account using I don't know adjacent so here my window was a bit not on the right side but I'm just importing adjacent and just shows you know the name and stuff and yeah so by the time I'm done with this process actually I'm done sinking you can see it it's synced and now if I click on an account it takes a bit of time to get the balance again it could be super quick this Wi-Fi was not like awesome okay now it's dated and I have near C20 token as the other one the other balance so here for instance I can add I don't know another token so it's gonna be a fake token it's my token so it's just tip coin and yeah you know at some point it just updates and to send a transaction so I'm just gonna click on this one and I'm just gonna you know say to whatever these amounts I can select the amount of way so here it does some call right it does like okay how much this transaction is gonna cost etc does some calls in the background and then right you send us a transaction like nothing nothing very right so I'm just gonna cut this because it takes some time to send the transaction but you you get it so what do we do now with this application so it has been audited this is the first time I say it actually it has been audited this summer by Trail of Bits I'm super happy because there was no big critical problem found we fixed actually all the problem now and we're gonna have a release probably next week with everything fixed and we want to give this to the community if anyone is interested to actually keep this going because this is not something we're gonna go further on we do not have the bandwidth for this and yeah so if anyone's interested please talk to me and we'll be happy to to yeah go on with with feather because I have a bit of time I'm also having a shameless plug here we're hiring a full-stack developer we have awesome other stuff to do with the light clients with many many things and please yeah talk to me or anyone apparently that's about it we have a couple minutes for questions thank you so much and yeah if you have any question


on the top of this TV tray white to give it a nice base. I've already sanded it with 220 sandpaper. Give that some twos for this primer. I'm just gonna be like, every time you go to someone's house, you didn't have to do TV trays. What's the deal? Easy and quick? When you ever see a TV tray look like this? Not never. So that's the thing. Once you get it to the point like this where there's no paint coming off, just leave it. This side's roll is a slide. Give me pressure on that. Can you imagine if we had like a crack in this? Like if we just like cracks from that, it would look like a piece of granite. I'm gonna do that one day. I'm going to TV tray the whole lot of wreck to do that. This is gonna look cool because that clear I put in there had just a little bit of white. So it's not gonna be completely all white. There'll be some clear in there. So it'll give it some crazy depth of clear and white and some colors. Cool. Yeah, it'll look good. I'll try not to mix it up. Like I don't like to mix it up when it does that. Cause then I'll just become one color. Yeah. It's already starting to sell up. I'm trying to send that in the right here. Yeah. This is cool. I don't know if this is gonna be heavy enough. I'm afraid it's like too light. Okay, I'm using Eric's words. That's bananas. Yeah. I'm telling you, these colors are great together. I was worried about much of the colors, but not anymore. No way. That is bananas. These colors are, they go so well together. Do you need another sheet? Done. That's the one thing about this is when I do it, and I just want to keep doing it, but you can't. You have to stop. It's like a poker game. It's like you win all the money and you're like, but I want to keep playing. Get your money and go. Yeah. You've won your money back. Now go. Now what we're gonna have to do is keep an eye on this and see which way this thing is unstable. Cause if we just leave it and it's like tilting this way, it'll all eventually just, so we have to like watch it and put a popsicle stick, you know, just kind of see where it's, it could be, it could be level. Yeah. Oh, that's awesome. Yeah. Micro cells. So what we need to do is we'll move it somewhere where there's no drips so that we can see where it's going to. No, huh? That looks great. That's like the perfect amount of stone coat. Isn't that gorgeous? It is. I love the colors you put.


that is on the optical fiber dispersion. So these are the learning outcomes. At end of this session students will be able to illustrate the dispersion losses in optical fiber. Now before starting to this lecture just recall how many types of losses we have studied in the optical fiber here. So we have studied almost two to three losses which affects the signal while transmitting in the fiber optical cable here. The first loss what we have seen was the absorption loss here. So the absorption loss was the imperfection of due to the atomic structure of the fiber materials. So in which it can be an eccentric and the eccentric here. So in eccentric we have seen that is the transition of an electrons from the lower energy to the higher energy state here. So due to which there is a loss of signal in the optical fiber. An eccentric in which the water molecules gets affected in the signal. So that is known as the eccentric losses. So after that we have seen the scattering losses. In the scattering losses we have seen the release and my scattering. The light gets scattered when the operating wavelength is less than or greater than the operating wavelength in release and my scattering respectively. And we have seen the bending losses also that is the micro bending and the micro bending that is the manufacturing losses. So we can overcome that losses while we have to make the new optical fiber. The dispersion loss is a little bit different as compared to the absorption the scattering and the bending losses here. So we will study now regarding to the dispersion. So let us understand first what do you mean by the dispersion here. So this is the fiber optical cable. This is the core inside which the light is going to be transmitted and this is the cladding here. So when the input pulse we are going to send that is 1 0 1 0 1 0 that is on off of the LED or the laser as a source here. So we are going to transmit the signal. So over a period of time that is when the signal is being transmitted inside the fiber optics cable here. So there is an overlapping of two signals that is we have seen that is the signal 1 0 and 1. So inside this due to the refractive index of the core there is an overlapping of a signal here. When the output is received at the receiver side here so the overlap of the pulses will takes place. It is indistinguishable pulse says we cannot distinguish between the 1 and 0. So such case are also known as an interference ISI that is inter-symbol interference. So we will not be able to receive the signal properly at the receiver side here. So in short we can say that when the optical signal or the pulse guided into the fiber optics the pulse gets spread and broaden as it transmit through the fiber here. Such type of occurrence is called as a dispersion. So what is the effect of the dispersion? The spreading of an optical pulse limits the information carrying capacity of the fiber. Means your fiber optics will not transmit as the data should be transmitted here. So how we are going to overcome this the dispersion losses here. So there are we will see now there are the two types of different types of dispersion in the optical fibers that is the intra-model dispersion and the inter-model dispersion here. That is the intra-model is also known as the chromatic dispersion which occurs in the all types of fiber means the it occurs in the single mode as well as in the multi-mode here and intra-model dispersion occurs only in the multi-mode it doesn't takes place into the single mode because only it transmits the fundamental mode here. So now in detail we are going to study about the intra-model and the inter-model dispersion here. So the intra-model dispersion is nothing but it primarily depends on the fiber material. So the fiber material used for the manufacturing are the silica and the OH bond like this okay the SiO2. So in that depending on the fiber material again there are two types of intra-model dispersion that is the material dispersion and the waveguide dispersion here. So now we'll see the in detail what do you mean by the material dispersion here. So the material dispersion takes place due to the different wavelength traveling at the different speed inside the fiber here. So the different wavelength traveling at the different speed inside the fiber it depends on the the velocity of a light traveling inside the core here. As you know that in the step index and the graded index that is the refractive index is going to be changed in the graded index here. So the different wavelength will be traveling at the different speed inside the fibers here. So now we'll see the material dispersion that is we have seen that is the wavelength 1 and wavelength 2 is shown here. Same like this is core and this is the cladding here. So how we are going to minimize the material dispersion is that we can minimize by using the wavelength such as 8, 17 nanometers, 13 nanometers and 15, 15 nanometers wavelength which is also known as the zero dispersion wavelength that is ZDW here. So if you see only calculate the dispersion losses or the attenuation due to the dispersion so it will be minimum almost it is zero at 8, 70, 1300 nanometers and 1500 nanometers. But every time we cannot send the data through the light that is which is wavelength of 8, 70 or 1300 because there the attenuation losses due to the absorptions and the scattering is more at the wavelength if you use at the lower wavelength here. So that's why we have shifted that that is known as the dispersion shifted fibers here that is will be 1550. So where the dispersion losses are zero means the broadening of pulse will be less at that time and the attenuation due to the other effects also will be less here. So that's why it can be minimized by using such a wavelength here. When the wavelength is less than ZDW that is zero dispersion wavelength it travels slower and when it is a higher than the ZW it travels faster here. Thus the speed is changed and it is used in such a way that all the waves passing through the fiber will move with the constant speed and hence the material dispersion is minimized here. And this dispersion will not occur in the single mode fiber here it will happen in only the multimode fiber that is the material dispersion here. So now we will see the waveguide dispersion. The waveguide dispersion is caused due to the difference in the index of the refraction between the core and cladding. The index of the refraction means at which the angle is going to be refracted here. Means whenever you're going to incident the light that is a different wavelength that is lambda 1 and lambda 2. So it has been incident at the acceptance cone and it is going to be incident at phi 1 and this is incident at the phi 2. So there is a difference in the index of the refraction between core and cladding here. So waveguide means which will travels from transmitter to the receiver here which results in the drag effect between the core and cladding portion of the power here. So such type of dispersions are known as the waveguide dispersion here. So now we will see the intermodal dispersion. So now we have seen the intramodal dispersion. So the intramodal dispersion occurs only in the multimode fiber. So we will see in detail now that is the intramodal dispersion. When more than one mode is transmitting through the fiber they will have the different wavelength and will have to take different time to propagate through the fiber here which leads to the intramodal dispersion. So this is the lambda 1, this is the lambda 2 which will be received at the different speed and the different time at the receiver side. Then each mode will be different wavelength with a different speed. Hence they reach at the end of the fiber with a different time here. This results in the plers broadening here. Thus this can be a distorted pulse. Such phenomena is called as an intramodal dispersion here. So the refractive index for the single mode only the fundamental mode is transmitted. So there is no problem of receiving the signal at the receiver side here. But in the multimode whenever there is a more than one mode is being transmitted here. So at that time the whatever the signal is being sent here. So due to the refractive index of an core and the angle of incidence. So this lambda 2 will travel with a different speed and lambda 1 will travel with a different speed if it use at the graded index also and the step index and it will reach at the receiver side with a different time and with a different speed here. So what will happen? It will be the overlapping of the two signals will takes place here and which can be a pulse broadening. So such type of things are known as the intramodal dispersion here. So as we have seen due to the spreading of light or the broadening of a light in the optical fiber, there is information carrying capacity becomes less here. So if you want to calculate that how much is the usable bandwidth. So this is an example we have taken. So it can be calculated based on the bandwidth distance product and this value is also expressed in Hertz kilometer. If the fiber is having the bandwidth distance product of 250 megahertz per kilometer, and the length of the link is five kilometer that is the length of an optical fiber, then the usable bandwidth over the this link can be calculated that is usable bandwidth is equal to 250 megahertz per kilometer that is divided by five kilometers it becomes an 50 megahertz. So this is the usable bandwidth of an the information carrying capacity of an the fiber optics here. So these are my references. Thank you.


proud to partner with Google Pixel on this upcoming CCYAA celebrity classic game in Toronto Canada. The Google Pixel 7 Pro has the most advanced pixel camera yet so we can capture everything leading up to the game especially my new haircut. Switching over to the Pixel was easy but training for the game takes focus. You got to eat right or at least deliciously and practice on hardwood to the gritty concrete to even waterfalls and fountains and definitely the weight room. I mean don't skip leg day. It has multiple options for slow-mo cinematic mode and a super red zoom up to 20x. For photos it's got action pan plus night sight because you know playing against Simu and lean to D it's gonna require some extra late-night workouts. Growing up we always wanted to play pro ball but we realized soon that you know we lacked the height athleticism wingspan and training but you know what we never lacked in passion for the game so thankfully CCYAA makes us feel like we're playing in the pros. Google Pixel 7 Pro. See you at the game.