What so please if we go ahead? Awesome. Thank you so much so There are two communities that I want to talk about one of them As was stated, you know, I have been a contributor and kind of a community member in the kubernetes contributor community for a while now, but also there was a local meet-up that several friends of mine and I happened to run So these pictures are relevant on the left is the kubernetes contributor community and on the right Like I said, it's a local cloud native meet-up in Ann Arbor, Michigan Called orchestructure. So thank you know orchestration and infrastructure Merged the two words together Mario one of the founders thought he was clever. It's pretty good name The two communities are of completely different scales But their state before and during the pandemic is still worth comparing and contrasting And ultimately, I think we can learn some lessons from where they were to their current state right now Hide cool So let's first talk about orchestructure Orchestructure started in early 2017 and it was founded by Mario Loria But shortly thereafter a group of us got together and kind of became the four main organizers. It was Mario Loria George Castro Bob Killen and myself It was a monthly meet-up that occurred on the last Wednesday of every month in the in the evenings around 6 p.m our time We usually provided some form of dinner Whether it was pizza or whether it was sandwiches we tried to provide for everyone that showed up and it was typically local speakers to Ann Arbor and We tried to have a rotating venue using companies both startup companies and well-established companies that were Ann Arbor focused so Anywhere from we were hosted by the University of Michigan and duo to some small startups like Alpha Django and bunch of co-working spaces And this picture is actually from one of the weekend workshops that we had done So the end of February of 2020 was like most of our other meet-ups our attendance was a little light But that was partly due to roads being slick and snowy and icy Because we just had a random end of February snowstorm There was some talk about covid, but it was more of concern for upcoming travel for a couple of the attendees And nothing we figured would impact the meet-up at all Um, usually we would see about 65 percent of the people who signed up through meet-up They actually showed up And for years, this was a solid metric whenever we were planning food. Of course everything revolves around food We also always almost had our Events planned about a month in advance So we could announce and promote the next month's talks and speaker to everyone who attended And it also let speakers that were local or could actually make it A chance to attend a meet-up and then see the tone the setting and make sure you know What they were thinking and how they were going to present would work out well And I think it was a Two to three weeks after the February of grpc talk that we wound up cancelling marches meet-up because of covid However, we organizers we did have an idea for how we could try and keep Orca structure going and keep the community engaged And that was youtube Early on we streamed all of our previous meetings to youtube from the almost very beginning We were streaming to youtube A while ago years ago at this point Google hangouts before it became google meet actually supported streaming directly to youtube And this made the setup for us Very very simple So we would just have a laptop setup in front Be able to click stream to youtube have it logged in as our orchestra youtube account boom We we have live streaming in our in our meet-up. It was really nice And it was also a great way to reach attendees Who might not otherwise have been able to attend due to traffic Distance or other obligations like you know a new baby Um, so it it was very valuable to us and we thought you know Maybe we should try and use this I mean oftentimes we had two to five people who would tune into streams for our old sessions And you know, we considered that a win. It was actually getting used So we had experience with streaming orchestra to youtube And we also had a community that was used to tuning into youtube and the streams and interacting with the presenters via via chat So we figured this is probably going to work out for us So in april to dog food our own idea We decided to do an orchestra session on k3s, which is a lightweight kubernetes distro And it's also an easy way to spin up a local kubernetes cluster Our goal here was to keep things very simple loose and really just focus on the attendees and engage with them live Have them ask questions and test things out that they may just you know, want to see done live It was a hit Not only did the panel AKA us the four organizers have fun But it was well attended with about 30 people and we received a lot of positive feedback And so that's that's the pattern that we followed We've normally done workshops in june And with summer starting we decided to take a break in june Which is you know nice for us in the midwest happens to get cold summer is something we always look forward to And then we had to skip august because we couldn't get a critical mass For even an online meetup And it was after the september meeting that the four of us started having a hard conversation At prior meetups, as I said, we always planned on the 65 percent rule 65 of the people who signed up would attend When we switched to the online meetups that dropped dramatically and over time By october less than half actually attended it turns out When everyone's attending online meetings all day an online meetup in the evening It's kind of a daunting, you know task even if it's a stream even if they're not even interacting with things It's just additional screen time Plus organizing an event no matter the size is exhausting The four of us had a really solid system Before covet who was responsible for what they were occurring to do this who was going to order the food Who was going to knock out lining up the speaker talking with the venue Everything would come together and we would try and share the load pretty pretty well But between our day jobs our own screen fatigue and feedback from our community We decided to pause the meetups As a total aside massive props to all of the organizers for this it has been awesome So what is the current state of orchestructure today? From the beginning and though alluded to on a previous slide Orchestructure has had a thriving slack channel On an Ann Arbor specific slack workspace People come in there all the time for Kubernetes advice CICD questions Pretty much anything in for coding related is fair game in there And it's probably you know a question or a topic at least once every few days Which to me considering it's a local slack with about 150 to 200 people. I'd actually have to look I should have That's that's really good in my opinion. That's that's pretty engaging So now that's the story of orchestructure Let's switch gears a little bit and talk about the kubernetes contributor community Kubernetes is at the center of a lot of different technologies But people are the center of kubernetes So this is this is a community that has thrived since 2014 Most contributors interact almost exclusively online Though when there is a kube con cloud native con The community tries to make an effort to come together with a contributor summit Through a website the cncf runs calls dev stats We can actually see the volume of github interactions on a given cncf project github or kubernetes is no exception And this is an interesting metric to look at Especially since you can't actually see when the pandemic started shifting things. It's It's a pretty solid pattern from, you know, january 1st all the way through july 1st I could have gone even longer, but I didn't think I needed to And why most people exclusively interacted with each other online and it was mostly asynchronous When we did come together for contributor summits, the content was often an even mix of hallway track structured sessions and Of hallway track structured sessions and working meetings The hallway tracks were organic conversations Friends could catch up just, you know, kind of Have fun There were structured sessions where we would have presentations on topics like how to fix test flakes How to become a better pr reviewer And then there were working meetings even Where there would be things like doc sprints or a release team would do a planning meeting But no matter what it was super productive time, even when it was, you know, meant to be a relaxed environment Yeah, uh, unfortunately The time where we could see the faces behind the github handles had to be canceled because of cove it And because of the contributor feedback, we actually canceled the kubecon eu 2020 contributor summit before kubecon itself made an announcement We noticed that company policies were already starting to hit and we had to make a difficult decision because Most of our attendees weren't going to be allowed to travel Another thing that we noticed was Unshockingly online meeting fatigue There are many contributors who get to work on kubernetes as part of their day job But there are also many who don't So these online meetings were a good way to get face time with each other and collaborate But What happens when you have a day job and also now you're trying to get into these online meetings Screen fatigue So as much as we try to work asynchronously, there are just some instances Where real-time communication using something like zoom is drastically more efficient than github issues threads or even slack So across the board attendance to these working meetings started to decrease As attendees pushed towards even more asynchronous meetings and slack threads instead of another video call that they might have to attend And it was to the point where our monthly community meetings A meeting the whole project. I mean not, you know, the several thousand contributors But there would be like good representation across the project Would usually rally around And these meetings began to drag and lose attendance This was a meeting where we would have sigs or special interest groups attend and provide updates update the community with the state of the upcoming release And allow members to bring up any issues or just cool stuff that they wanted to share kind of like a show and tell Unfortunately, it became quickly became yet another meeting For many and as people tried to thin out their schedules This was one that didn't make it into their schedules Another thing that happened was our release cycle shifted Previously kubernetes would release quarterly with q4 being kind of a lighter patch release due to holidays During 2020 it became clear that the releases needed more time given the new circumstances So we shifted our release schedule now to three releases a year But where there was doom and gloom there was also fun to be had An untitled goose game themed ctf was hosted by the community in march This provided many with an early distraction to the impending separation the pandemic would cause And while a contributor summit never happened we instead tried to have a little fun for our community We attempted to foster the same kind of feeling as best we could That a hallway track would give us while also giving our community members an outlet of just energy and fun by way of video games But not just video games were had We also did things like a cloud native bake-off where a bunch of community members got together and streamed themselves baking cookies And there was there was an entire judging panel. It was awesome We also presented community awards the whole goal as it says was just to relax and have fun Feedback was positive. So I think mission accomplished and that's how things progressed through 2020 by the end of 2020 and beginning of 2021 the community was more or less in a slightly more stressful due to world circumstances status quo There were minor tweaks to some project-wide processes to make things even more asynchronous friendly But in general the community stayed close and stayed strong So what's the current state of the kubernetes community today? well Thankfully, we are back to having in-person contributor summits while also having an end of year contributor celebration We have another contributor summit scheduled for kubecon eu in valencia And planning has started for kubecon na contributor summit in detroit. I think that starts after kubecon eu though I think they're trying to form the team right now And asynchronous practices are being pushed where possible And contributions still follow at the pattern that we've seen One thing to call out If you noticed the the scale on the left of these charts GitHub activity has decreased overall in the project But we're not going to speculate to hear as to why I have my own thoughts So One community was driven by mutual goals and was engaged primarily Asynchronously the other was a community driven by mutual interest But without any goals beyond networking and mutually nerding out So without engagement it became apparent that the in-person meetup wasn't sustainable as it was before even with virtual events So there are a few lessons learned I want to kind of go over these and then I like Especially with these topics leaving time at the end for a lot of questions because I tend to work better off of questions One of the big things that we learned was asynchronous activity Is the best way to build a community because it allows people to Engage with you at their own pace It it just really helps It also lets you build a more global community, which is something we need to start doing even more of Yes, even now where you know having face-to-face time it is 130 my time in the morning You should probably have more coffee, but you know asynchronously More people can engage with you Active engagement is also huge one thing that we learned between And the kubernetes community is orchestra was not as Not as engaging to the attendees as you know the kubernetes community because Kubernetes contributors are contributing to something The orchestra meetup was just the attendees would come and attempt to learn something When you have the ability to do fun things like Not necessarily just live demos, but like hackathons when we uh orchestra had the Workshop where we actually had people sit down with their laptops and You know follow demos along and we had people running around helping to make sure everyone Could actually do what they wanted to do It was just a much better experience for the attendee and for the organizers because it's just far more satisfying This to me is the uh the motto if you want to be a good open source contributor But it's the same when you are both attempting to run a community and also attempting to Join and contribute to a community Be consistent If you say you are going to do something Do it if if there is no It's better for you to be honest about not being able to do something And being honest with yourself about it. So for example If I know that I can review one pr a month But I always review one pr a month that kind of behavior gets noticed because you are being 100 consistent Also, if something happens if you're moving and you're not going to be able to review that pr communicate that And then just put the two together always make sure you are being consistent in your communication While this is more of a contributor focused slide The same thing happens when it comes to organizing events and organizing meetups and trying to manage a community you have to establish A baseline for the members of the community to just have faith in what you're going to do and what you know is going to be I don't know available This is my own personal opinion, but it has Kind of been tried and tested and true Always shoot for fun over formal There is a time and place for being formal, but I want to say 80 of the time even in like most of my career Fun has always been the way to make more people engage with you Have silly funny things put memes in your slides Try and come up with you know a ctf game that's based on a goose game, you know it People want to have fun That like it is in people's nature to have fun the definition of fun may be different But chances are if you're in the tech community and there is some interesting thing That involves a game or involves a mental puzzle or a process Most of the time people are going to be all about that So people make open source people are the fuel of open source Whether it's fueled by passion or it's career driven or people just want to have fun People make open source possible But people are also social creatures So we need each other and we need the connections between each other And when we join together, we are definitely greater than the sum of our parts That's that's kind of what community is all about So please go forth collaborate and make friends And I'm actually going to click on the chat now and read a bunch of stuff because I want to answer people's questions


Hello, I am Dr. Satish Kumar Skashid, Professor in Civil Engineering at Balchan Institute of Technology, Sulakur, presenting a topic, Fundamentals of Unit Hydrograph. Learning outcomes of this session, the students will be able to define the concept of unit hydrograph. The students will be able to state assumptions in unit hydrograph theory with the logic behind it. The students will be able to state significance of unit hydrograph for computing ordinates of stream flow hydrograph. Coverage in this presentation, just to have the idea of floods, flood pictorial views, the rainfall and off process we will discuss in brief. Typical stream flow hydrograph we will discuss and then we will come to unit hydrograph and its significance in predicting hydrograph. Now this is a typical picture which shows us a flood. So this can tell us how important it is to predict stream flow. The stream flow comes from a catchment. So how the catchment characteristics influence the hydrograph that we should know and how a particular rainfall event can be used to define the unit hydrograph that we learn. This is another picture of flooding on the Picos River, New Mexico. We see the spread of water on both the banks and hence the importance of stream flow prediction one can understand. This is an aerial view of the flooded Ganges in Alaba city. This particular figure shows you the process of precipitation, surface runoff and groundwater flow to which we are quite familiar. So when it rains some flow infiltrates some water comes out as overland flow some water again penetrates into soil and again comes out as interflow and ultimately we find a contribution of the surface water to the channel. This is typical runoff hydrograph. So this is say day 1, day 2, day 3, day 4 and on this bi-axis we are showing two things. One is rainfall in millimetres. So the variation of rainfall in millimetres typically it is shown in this way and another is the runoff in cubic meter per second. So the blue part gives us the storm flow, surface water flow and this yellow part shows us the base flow or the groundwater flow contribution in a hydrograph. Now let us come to a definition of unit hydrograph. A conceptual direct runoff hydrograph resulting from rainfall excess of unit depth and constant intensity for a particular watershed is called as unit hydrograph. The unit hydrograph method is employed to calculate the direct runoff hydrograph at the watershed outlet given the rainfall excess produced by the storm event. We will discuss the things in details. In unit hydrograph method the method is categorized as a lumped model in which the hydrology characteristics of entire watershed are combined and typified by one or more parameters. A simple mathematical expression or graphs. The unit hydrograph is a useful tool in the process of predicting the impact of precipitation on stream flow. The unit depth is 1 centipede in SI units or it can be 1 inch in US system. It is usually abbreviated as UHC. The subscript C indicates the duration of rainfall excess. Rainfall excess means it is over the percolation and evaporation which is ultimately converted into surface flow. Let us take one example. For instance the direct runoff hydrograph produced by rainfall excess that is a duration of 3 hours. What I say duration of 3 hours and constant intensity of one third centimeter per hour is denoted by UH3 that is unit hydrographs of a 3 hour rainfall event or 3 hour unit hydrograph. So here one can understand that 1 centipede rainfall excess has taken place in 3 hours. That is why it is called as 3 hour unit hydrograph means unit means 1 centipede rainfall excess has taken place in 3 hours time. You can develop a unit hydrograph for a gaged watershed by analyzing the simultaneous rainfall and runoff records. Unfortunately most small urban or rural watershed are ungaged. It means we do not have the rain gage stations there. We do not have the stream gaging there. So there what happens we do not have the recordings. In such cases we can also go for a synthetic unit hydrograph method to tackle such problems. Now why to have unit hydrograph? So it simplifies our task or procedures and it gives a baseline for a specific watershed. It standardizes the hydrograph for different watersheds and it gives us the information that how the flow of a stream will be affected over time by the addition of one unit of runoff. The role of unit hydrograph theory in the flood prediction process is to provide an estimate of stream flow given an amount of precipitation. It means if we have a watershed, its area and its rainfall records spread over time and we should be able to convert that particular information in a probable stream flow varying with a time. For that purpose we need a hydrograph. Once we know how much rainfall or snow melt has occurred or is likely to occur and we have an idea how much of this will turn into runoff, we still need to know how the flow of stream will be affected over time by the runoff. The unit hydrograph provides us a way to estimate this and is an integral part of many hydrological and modeling systems. Now here we will understand the flood prediction process and it will tell us how unit hydrograph helps us there. So once we know the watershed conditions, how will the water move once it reaches the ground surface? Then once we have the rainfall information, how much rainfall and with what intensity it has rained, we have a snow melt information, how much snow melt is there and how it is going to melt with the period of time. Then the next step is to understand runoff processes, how much of the rain water and snow melt will turn into runoff. So here we give the input from a unit hydrograph, how will the runoff affect the flow over time, also we give the information of flood frequency, how often and how big are the floods over the long term. Almost here also we have the role of river ice, how does the river ice affect the moment of water through the stream channel. And then we will come to flash flood processes, how do rainfall and land use combine to produce a flash flood? How stream flow routing has to be done? It is how certain volume of water flows through a channel over a period of time. Then we also give the stage discharge relationships to this particular information is given here. So ultimately we get a hydrograph of a particular river or particular stream which will give us the variation of stream flow over a period of time. So this is the flood prediction process. Now there are certain assumptions in unit hydrograph theory, why because rainfall is a natural process and we need to approximate certain things when we are going for a unit hydrograph. What are those assumptions? The primary assumption of unit hydrograph theory is that the rainfall has uniform distribution both in space with minimal variations across the basin. And also unit hydrograph theory says that it has uniform distribution in time also. In other words, the rainfall rate did not vary much during the event. Secondly one should understand in reality precipitation events are rarely uniform in space and they are rarely uniform in time also. One portion of the basin experiences higher intensity of rainfall and other experiences small but still we need to assume this so that we get a unit hydrograph which has to be useful for prediction of further stream flow. The next assumption is that the base duration of direct turn of hydrograph due to an effective rainfall of unit duration is constant. The ordinates of direct run of hydrograph are directly proportional to the total amount of direct turn of of each hydrograph. It means here we are taking the principle of linearity, superposition and proportionality so that the computations can be easy. For a given basin the run of hydrograph due to given period of rainfall reflects the combined physical characteristics of a basin which are time invariant. So this picture shows you that though we say that the precipitation will be uniform all over the basin still we will find that the precipitation varies over the basin. So some approximation we need to do that you can understand. So here on this basin we find the intensity of rainfall is changing, here intensity of rainfall is smaller. So we need to do averaging over. Let us take some questions. A unit hydrograph has one unit of rainfall duration, rainfall excess, time base of direct run of discharge. One more question. Excess or effective rainfall may be defined as the amount of rainfall which produces equal run of total rainfall minus infiltration minus losses, water depth collected during the net supply interval for all the above. And these are the answers. A unit hydrograph has one unit of rainfall excess and excess or effective rainfall is going by all these 1, 2, 3. These are the references. Thank you.


How can I add groups to my courses? First, let's look at two Moodle terms for groups of users. A cohort is a group of users created by the admin and available throughout the site or a category. You can enrol a cohort into a course when users are added to or removed from a cohort they will appear or disappear in the course where they're enrolled. A group, as Moodle uses the term, only exists within a single course. A course can have several groups and the teacher can create these manually or the admin can upload them with a file. This video looks at groups in courses. If you need to create cohorts, watch our video on how can I add groups of users to my Moodle. Groups can be added to courses either by the administrator with a text, CSV file upload or by the course teacher within the course. Let's look at both methods. File upload by the admin. If you are the admin, you can create groups in a course and enrol students in them at the same time by including the relevant columns or fields in your file. First, we need to prepare our file offline. We can either use a simple text editor such as Notepad or Get It or use a spreadsheet program such as Excel or LibreOfficeCalc. If you can use a simple text editor, it's better because sometimes saving in Excel can cause problems. Here is an example of a text file which shows the user name, course name and groups. You need the short name of the course and if the group has not been created in the course it will be created when the file is uploaded. Our users already exist on the system. We make sure the file is saved as a CSV file and then upload it from Site Administration, Users, Upload Users. Here we preview the file and can check certain settings. Then when we upload it, the groups are created and the students enrolled into them. Manual group creation in a course. As admin or the course teacher, access the course and click the Participants link on the left. Then from the gear icon, click Groups. Click the Create Groups button. If you're interested in the other two options, Auto Create and Import, find out more in the documentation. Here we must give the group a name but other settings are optional. If we need learners to enroll themselves into the group, we can set an Enrollment key and tell it to the learners. The documentation explains more. We can also add a group picture which identifies the group in forums. Then to manually add learners, we select them from the box on the left and move them into the box on the right. We can go back to the groups and repeat the process to add more groups. And here the Participants list shows who is in which group. To summarise, Moodle Groups uses in two ways. Site or category-wide cohorts and Course Groups. Groups can be created and uploaded into courses by the Site admin and Groups can be manually created in courses.