Also cause also help on me.
Chukwuebuka Nweke: confirmed this. So in our project. With regards to, we're trying to reconcile the bias that we found when we're doing our validation studies for for the basic effects in in the in this, in this error, in simulations
Chukwuebuka Nweke: using the protocols that are related to shot cyber shade for the to to the simulation platforms. and during that time we found a significant amount of bias. When we, when we were comparing
Chukwuebuka Nweke: the simulation is to the
Chukwuebuka Nweke: the grandmother's, and and also and also compared to the observation. So we're trying to figure out
Chukwuebuka Nweke: what's calling that buy. So we we we had a recent schedule that was funded to look at this problem, and we were looking at it from, based on the on the data that we had prior.
Chukwuebuka Nweke: So we looked at it, and we added: so, during the course of our announcement assessment. we just, we. We believe that we should try to add, add more sites
Chukwuebuka Nweke: to see if that gives, if that changes, or if that kind of reinforces what we're finding.
Chukwuebuka Nweke: So we did in the the assessment from the the data versus the empirical ground motion side. So we wanted to run the same. The same things on the the 3D simulations.
Chukwuebuka Nweke: But I believe, Robin suggested, or doing our our individual meetings, that
Chukwuebuka Nweke: because the on d is not so, I guess I I I' to select me if i'm using the wrong word, because the one d is not a is it? It's not a bad approach. We would like to run the one d's first
Chukwuebuka Nweke: and see what it looks like before. We then go back and run the 3D's in the future. So we're trying. We're trying to run one. We're trying to run the simulation using the on the
Chukwuebuka Nweke: play. A plane layer of velocity. Mars is that I think that's the right word.
Robert Graves: Yeah.
Robert Graves: yeah, yeah. So that's that's a a, a good summary, and and just to add a a couple of points to that
Robert Graves: in in the original modeling.
Robert Graves: So I I ran 3D simulations. These are: These are small or relatively small events. Magnitude for maybe up to 5.
Robert Graves: And
Robert Graves: I did that. and it's all of a large part of Southern California. So I ran those on Frtera.
Robert Graves: So the 3D simulations are computationally intensive.
Robert Graves: Booka had mentioned the bias that we had observed, and it was rather significant, I mean in under so the simulations just kind of across the board. How long periods under predict
Robert Graves: the data?
Robert Graves: And so my thought as an attempt to reconcile. That would be to
Robert Graves: adjust the scaling or well, the the the magnitude Area relation.
Robert Graves: Now they're small events, but
Robert Graves: they do. When I ran the simulations. I used to
Robert Graves: kind of a just a generic scaling relation to get.
Robert Graves: you know, an area for each magnitude.
Robert Graves: because this is probably going to be an iterative process, you know. I'm not exactly sure how to adjust, and we'll do it on an event by event basis. So, in order to make it kind of feasible from a computational perspective. That's the idea of using the Wendy simulations.
Robert Graves: That was book that had had alluded to. You know the Wendy is, is the approximate
Robert Graves: the base in response, or maybe not capture the base and response. And that's another aspect of it. But the first order we're hoping that we can make some progress and come up with
Robert Graves: a better sense of what the scaling magnitude area scaling should be for the smaller size of events.
Robert Graves: And then, you know, depending on how that works out.
Robert Graves: If it works out well, we have some updated scaling relations, you know. Eventually, maybe we go back and redo the 3D calculations.
Robert Graves: just as a kind of a confirmation on all that.
Philip Maechling: So can I ask You follow a couple of follow up questions, so.
Philip Maechling: So i'm understanding. You are running historic.
Philip Maechling: moderate, historic earthquakes.
Philip Maechling: And and where are they located?
Robert Graves: It's in? Yeah, it's a well Southern California region, but most you know, kind of La Region is, but you know out the desert, and you know, surrounding areas, and they're all
Robert Graves: do. We have? Well, 13 original. But now we are. We're up to 27 events. So plot of view of the map.
Chukwuebuka Nweke: Yeah, sure. Just give me 1. Second.
Robert Graves: Yeah. And
Robert Graves: And this is also we're looking at 1 s period and longer.
Robert Graves: So it's it in that sense it it, you know. It's not broadband.
Robert Graves: but
Robert Graves: we can use the the modeling capabilities of the platform for those longer periods, you know, we could actually do them broadband, and you know we'll get everything. Oh, go ahead!
Sajan K C: This this black books over here. This this this is our study. Reason and the do we start over? Here are the Arthuric events that have occurred in Southern California reason, and have been recorded in our study. Reason, which is this black box over here
Sajan K C: and in the ready start Over here are the Inesl 13, or to give it events, that for which we have already performed the simulation.
Sajan K C: and we needed to
Sajan K C: the it more our specimens in our database. So we have selected 14 or 6 events which are in the white stars, and so they are. They are located within this this rate boundary over here, which is a arbitrary boundary that we created just to make sure
Sajan K C: the that we have selected are very close to our study. Reason
Chukwuebuka Nweke: also. Also there's one more events
Chukwuebuka Nweke: that's located by the so by by Anza.
Philip Maechling: it's got this. It's. I I think it's it's missing from this, but it's just located over here. so we can we we did that we did have to try and get a good coverage of our region, because all this, all the sites are within a black box.
Philip Maechling: Well, I mean just to jump right into it. One of the you, the key ways we I talk about the broadband platform are
Philip Maechling: assembling your input your input data, and you know configuration for your simulations. So one of the key things I think you'll face is what which oned velocity model you want to use.
Philip Maechling: So let me see. we've got
Philip Maechling: a map. That kind of shows.
Philip Maechling: Here's the different regions for that where there are
Philip Maechling: on the velocity miles defined for broadband platform.
Philip Maechling: and
Philip Maechling: i'm not. It looks like, yeah, Well, can I share that just to i'm gonna grab the screen All she
yup
Philip Maechling: show you just what i'm talking about here. So
Philip Maechling: this is one of the kind of the regional
Philip Maechling: definitions that's using the Broadway platform. And when you're simulating events, since these are different on d velocity models that
Philip Maechling: you'll select for your simulations. So.
Philip Maechling: And then these are kind of examples of the vertical profile.
Philip Maechling: So it was
Robert Graves: to me. I don't know. Maybe it's obvious, is it? La Basin? That would be most appropriate. Yeah, the and actually we so we did for the original 13 events. I did run
Robert Graves: when a Wendy model as well.
Robert Graves: you can. Actually, I have to go back and check if I ran that on frontier, or you know how I actually get it.
Robert Graves: But we use what you have shown there. La Base and 500, I think we called it, or I called it the North Ridge
Robert Graves: area, but that that corresponds on your map that we correspond to the so Cal region there. And and I think we because we're just. We're really kind of looking at a at a broad brush here, initially.
Robert Graves: just using the same model for all events, regardless of you know, if it crosses that boundary into what's labeled the hobby or something I I I don't want to
Robert Graves: worry about that
Robert Graves: because those differences are going to be rather minor compared to what we're looking at in terms of source scaling.
Philip Maechling: Okay.
Philip Maechling: So to me, that's one of the things that you kind of inputs that you assemble.
Oh.
Philip Maechling: one want to express kind of another key input would be to your station list.
Philip Maechling: So this is, and I think this point, since it's a validation, events where you've got observations you would put in basically the lat long of the various stations where you have observations.
Philip Maechling: There's some additional information in here. Vs 30.
Philip Maechling: And what the frequency response of the instrument at that site is, or for the recording.
Philip Maechling: and I not sure.
Philip Maechling: I mean, I would go to maybe
Philip Maechling: seismic network, the California data Center or cosmos to get the frequency response for individual instruments. But just kind of expressing that something, you'll probably
Robert Graves: Yeah.
Robert Graves: So it this to jump in here, they so those parameters are available.
Robert Graves: And
Robert Graves: yeah, so I think that, you know, would be able to construct this kind of a file.
Robert Graves: you know, and and it, and maybe there's a a couple of ways to do it. One way would be to just have one file
Robert Graves: of stations
Robert Graves: for everything right, and we use that for all events.
Robert Graves: Not necessarily that each event has observations and all those sites. But then it just, you know, just makes it easier. The you know the platform maybe runs a little bit longer, because it has more stations. But
Robert Graves: in any case
Robert Graves: the those last parameters that you have there, the the low-pass frequency, high-pass frequency.
Robert Graves: So those are available in the data sets
Robert Graves: my understanding of the way the platform works
Robert Graves: is it mainly utilize those for
Robert Graves: plotting purposes.
Robert Graves: I guess that's a question for you, Fabio.
Fabio Silva: There you go. Yeah, My My zoom was playing for it here.
Robert Graves: Yeah. yeah, so we can hear you so you
Fabio Silva: No, I couldn't hear you so hear your question.
Robert Graves: Oh, yeah, so i'm wondering in in the station file there are these parameters, the low pass and high pass
Robert Graves: frequencies.
Robert Graves: and I think those may only be used for plotting
Robert Graves: purposes on the platform. Is that correct?
Fabio Silva: That's right. So it it kind of. They indicate where the data is valid there, and that's you know, for for for comparison plots. We put those lines, the vertical bars, there, the dash lines there, and and for the goodness of it we drop those. So you know, data beyond those the the range gets. Rob, so it doesn't affect
Fabio Silva: the the the result.
Robert Graves: So actually, this this leads into another. I I guess the question, or or
Robert Graves: or discussion topic, and that is
Robert Graves: the so. These are historic events, they They have data, you know what they are recorded data.
Robert Graves: but I I think much of the analysis that
Robert Graves: will be doing, maybe
Robert Graves: outside of the platform.
Robert Graves: So, in a way, it's just utilizing the platform to get
Robert Graves: the simulated waveforms. And then Sergeant has kind of his own workflow that he's built up. you know, doing these other analyses that he that he could then.
Robert Graves: you know, pipe those into, you know, Calculate
Robert Graves: I I guess you could. You could do your own calculation of rot d 50, and then compare the sexual acceleration. I realized the plat that maybe overlapping with some whatever what the platform does.
Robert Graves: But does that? Does that make sense, Phil and Fabio, that that are are thinking here is that we're not going to necessarily use the platform
Robert Graves: in its full capabilities. But the you know the main part is to actually run the simulations and get those waveforms
Philip Maechling: good. Yes, that makes sense.
Philip Maechling: We posted an example of
Philip Maechling: kind of the outputs what this
Philip Maechling: something falls into the category of a validation simulation.
Philip Maechling: And we just wanted to show you the kind of the data products that emerge from that.
Philip Maechling: So
Philip Maechling: But
Philip Maechling: let me.
Robert Graves: Yeah. So i'm sorry to to interrupt. But another just one other comment on that data file.
Robert Graves: I mean the the station file. and you had mentioned it does have a Vs 30 value.
Robert Graves: and I just want to make sure for for sage on, and Buka's benefit. You know what that what that means, and how it's used in the platform, so that would be
Robert Graves: Vs. 30 that corresponds
Robert Graves: to the site, the specific value, right. You know, whatever that comes from Nga, or whatever
Robert Graves: the way that you, the way that it's utilized in the platform is that the simulation
Robert Graves: There's think of it as 2 steps. The the initial simulation is done for a reference site condition, and that is 500 meters per second. The S. 30,
Robert Graves: and then
Robert Graves: there's it's empirically based correction factors that the platform applies to
Robert Graves: on top of that
Robert Graves: to correct. so that it's appropriate for this value. So.
Robert Graves: and there this is something.
Robert Graves: or I I guess you guys, or maybe in consultation with me or and or John to think about is one way to do this would be
Robert Graves: to just do
Robert Graves: simulations and keep it at that reference condition. So we would put 500 in for every site right? And that would be analogous to what I had initially done
Robert Graves: with the Wendy simulations that I ran before they were those were all for that reference condition.
Robert Graves: Alternatively, we could actually
Robert Graves: add that correction in which I I think maybe the more appropriate thing to do it would for the longer period it's, maybe not going to be a huge adjustment, but at least it would be kind of moving things a little closer to reality.
Robert Graves: Yeah, anyway, I just. I I just wanted to mention that. So you guys are aware of it. I don't need to decide one way or the other at this point. But just just so. You're aware of how that would work within the platform. Okay, that makes that. I I think I think, when we discuss, I think we're leaning towards we doing about, I think that's
Chukwuebuka Nweke: well. Once she gets a a what sounds like it's a a good sense of it.
Robert Graves: right that we could move forward from that point on. Yeah, yeah, yeah, we can revisit that. But it, anyway, just wanted to mention it. So go go ahead, Phil. Pick up on that. Yeah.
Philip Maechling: to me the it one source where you might get the Vs. 30 is ucvm. You could put in the that long, and it'll return.
Philip Maechling: Yes, 30 from the recent Thompson
Philip Maechling: Statewide Vs 30
map.
Philip Maechling: I think, was 2,022 was released. So
Philip Maechling: so that's a just the source of that his new map and values are integrated into Ucvm, but I mean, and that. But if you use the Cvm. That's going to be the source. So I think there are other opinions on what Vs: 30 are.
Philip Maechling: Okay. So I just want to express. When you do a you do run a broadband. And this is an example of a Northridge validation. It outputs a collection of information.
Philip Maechling: so including, for example, that station that we were just looking at. So this is the station list where we had observations for North Ridge and the Vs. 30, and the information.
Philip Maechling: So this gives an example of kind of the inputs that we're selected. We don't talked about the source yet, but we'll want to do that.
Philip Maechling: Then there are kind of summary plots.
Philip Maechling: because we have observations
Philip Maechling: for this event. We can compare the simulated and results against observations. These are kind of the summary ones that, and you may be producing those. There's pictures of the source or the rupture file that was used.
Philip Maechling: But then there's access to the the size of grams themselves. So
Philip Maechling: the
Philip Maechling: upwards are
Philip Maechling: the results are output, as both
Philip Maechling: philosophy and acceleration.
Philip Maechling: and they're in something called bbp format. which is probably
Philip Maechling: you haven't used before it's we we we've we've. We've used this because I've been to the the same format that Rob provided. When Rob did his runs, it was this exact same.
Philip Maechling: Oh, good! So it's 3 component ascii. It's relative to start of rupture. So it's not. I mean aligning it with the observations is you'd have to ask Fabio how he does that.
Philip Maechling: But so it's not absolute time. It's the time is relative to origin start working.
Philip Maechling: But yeah, then it'll list each station. And I mean, you could retrieve and download and process these sizing RAM files.
Robert Graves: Yeah, so, Phil, actually, that's a question I hadn't thought about is, you know, a retrieving the data or accessing your data. So this you know it's
Robert Graves: it. It it's stored in some directory treaty or something. It may actually be
Robert Graves: easier, you know. Sergeant can just do a copy of the Directory as opposed to pointing and clicking.
Philip Maechling: Yes, so we'll express. So when you run to a a of the broadband platform. So that means you have a station list and a source, and you run it. Basically the results are
Philip Maechling: they're given the a unique Id. It's it's a time stamp. And but it's basically
Philip Maechling: some sense guaranteed to be unique. So each time you run the platform outputs go into it. It's a directory
Philip Maechling: with a number on it, and then
Philip Maechling: so i'm. Using this to the I ran this over on a.
Philip Maechling: So once we get your account set up.
Philip Maechling: So, John, we'd be able to run this or you'd you'd
Philip Maechling: It would produce outputs directory like this.
Philip Maechling: And then.
Philip Maechling: yeah, all of the files that are in there. So you can get access. The files will be on a
Philip Maechling: I don't know
Philip Maechling: directory over at sea. Arc.
Philip Maechling: What we're looking at is a index file that just helps. It makes it easier to sort through all these files, but the
Philip Maechling: both the size of rams, and the
Philip Maechling: images are all collected
Philip Maechling: in the output directory. So
Philip Maechling: okay, I have a I have a question.
Sajan K C: So when I compile the station name station. I'll add it to you with the Via study value in low pass frequency. So in what format should that file be? So that I input it into the burden platform, and as far as I know, that that file format needs to be converted into dot sdl format.
Sajan K C: which is the Bro. The Bv from it. Right? So should it be in the dot Dx: define or excel file
Sajan K C: that I need to.
Philip Maechling: What suffix is Stl. But it's a basically a text file. It's an Ascii text file. so it's not a excel. But I mean, you could
Philip Maechling: keep it in, excel and then export it into a text file.
Robert Graves: and I can. I so feel just in terms of the the way
Robert Graves: the codes would read this.
Robert Graves: I believe anything that with a leading
Robert Graves: ash
Robert Graves: character is just it's it's it's, it's a comment. You know
Robert Graves: the so the 2 comment lines. and then
Robert Graves: the data just in the columns and
Robert Graves: the columns eliminate. There is
Robert Graves: blank space, I mean it could be one blank space. I think it could be a tab. It could be 6 blank spaces, you know, but
Robert Graves: blank space. It just skips to the next call.
Fabio Silva: So so, Phil, would you? Would you like me to to show like a quick example how to run the road. But platform I show this files. I would like to maybe a a a three-station thing. I can do. That yeah, but yeah, let's do that. I want to just bring it up one other essential, because I think this is where
Philip Maechling: science input will be needed. So to me we the identified the inputs.
Philip Maechling: including the station list, selecting the velocity model, but not the important thing will be your critical One would be the
Philip Maechling: source file, and
Philip Maechling: this is something
Philip Maechling: we don't have, so
Philip Maechling: I i'm not sure where you're going to get this up
Philip Maechling: unless you've got sources for each of them.
Chukwuebuka Nweke: Can this for so far be made.
Robert Graves: Yes.
Chukwuebuka Nweke: so we. We have the information for most of these to make them.
Philip Maechling: So we want to express broadband platform. There's kind of 2 levels. There's a call. I don't know the simple source description.
So that's
Philip Maechling: doesn't have a lot of details about the
Philip Maechling: it was slip time history.
Philip Maechling: But it does define parameters the extent of the fault.
Philip Maechling: Yep.
Philip Maechling: Rick Dip
Philip Maechling: Corner frequencies. So model specific parameters, I think these.
Philip Maechling: you know, going to be
Philip Maechling: depend on which simulation ground, motion, simulation codes. You use this. These can change
Philip Maechling: so. But I I just want to express these all. You'll need these for each of the events that you're going to run.
Robert Graves: Yeah.
Robert Graves: so. And and this is kind of the key part of what we need to work with.
Robert Graves: So I and and I have this type of information for the 13 events we've already simulated
Robert Graves: for the additional 14 events I can help Saj on. Construct that.
Robert Graves: And actually, Phil, could you scroll back up to the top part?
Robert Graves: So
Robert Graves: w the the thinking, I guess my thinking on this in terms of how to how do we go about trying to reconcile this bias.
Robert Graves: We're
Robert Graves: generally under predicting the observed ground motions. So
Robert Graves: my thought is, well. Let's make the source higher stress drop or higher average slip that is, shrink the area down
Robert Graves: and the slip will go up. So the parameters there. The first one listed here is magnitude, and then that we have fault, link and fault with.
Robert Graves: And so those are the 2, you know. I I I ran initial model
Robert Graves: with based on a simple scaling relation.
Robert Graves: We'll just start shrinking those down, and that. And so what Sajan would need to do or need, you know, have to have access is to be able to
Robert Graves: got it. Create a source
Robert Graves: file, you know, For For each of that.
Robert Graves: you know. Run that
Robert Graves: and then look at the results and say, okay, yeah, that improved. But I still need to make it a little smaller. This is going to be a kind of trial and air. you know, and so then go back, edit the source file, do another run, and and proceed from there.
Robert Graves: You doing good
Robert Graves: and so fabulous. You were
Robert Graves: talking about an example, and so that
Robert Graves: now, with but with that in mind. So so this is going to be like I said. It's like a trial and error, or iterative
Robert Graves: with. you know, Saj. On having to make some changes each time
Robert Graves: it. It is a bit of a bookkeeping problem as well, or or or experiment or exercise, because
Robert Graves: you know there's
Robert Graves: 27 events, and there's, you know, multiple stations, and, you know, Get it. Keep track of all that. And then, and, as I said, we'll take the results. I mean the simulated waveforms, and then have to do his own post processing. So
Robert Graves: you know I I I just want to make sure that Fabio, you and Phil are kind of aware of of how
Robert Graves: or how we think
Robert Graves: we would run this, because it's maybe a little bit different than what other applications for the platform we've been.
Fabio Silva: I I I had. And so if you run one of those events, Rob, do you get a sense that you know how many realizations would you need? Or you just talk about one realization for each one.
Robert Graves: There, there's there's small magnitude. And so the I think one realization
Robert Graves: is
Robert Graves: is sufficient.
Robert Graves: A. And it's really well if you think about it. Yes, there are going to be multiple realizations.
Robert Graves: but it's going to require
Robert Graves: editing the Src file each time, and so in Buka, and for your benefit.
Robert Graves: what Fabio is referring to in terms of multiple realizations. The way the platform is set up is that you?
Robert Graves: You can specify those parameters in the station file and the general source parameters.
Robert Graves: And then you can actually run through multiple realizations which sample different slip distributions, for example, or different hypo center locations or different rupture speeds
Robert Graves: my senses for these small magnitude events, those features Aren't going to be as important as just the general scaling of the source size. Yeah, okay.
Fabio Silva: yeah, I can. I can. I can. I can show that a little bit. So if you want the
Philip Maechling: let me. I'm sorry. Just one more main issue before we before you do that. So
Philip Maechling: you want to express. You know the broadband platform.
Philip Maechling: It collects a number of alternative computational methods. I think all your activity. You're going to focus on the graves of the target method.
Philip Maechling: but I some of the kind of complexity, and the reason it takes, you know, a long time to install is there's actually a a collection of different methods available.
Philip Maechling: but the key components for the grip, target method.
Philip Maechling: rupture, generator, low frequency, high frequency, and then a site response MoD: so I
Philip Maechling: to me. That's another scientific discussion. Whether you include site response is that
Philip Maechling: I I I believe that that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's that's what you mentioned with regards to the the the adjustments
Chukwuebuka Nweke: of the the
Philip Maechling: Yes, I I believe we. We are probably going to ask. Yeah, I was. I was muted there, I think. But yes, you're absolutely right. Okay. Okay.
Philip Maechling: Fair enough. So okay, yeah, from you.
Fabio Silva: Let me just show. So a simple example. Just so you get a sense of how it works.
Philip Maechling: I make sure that
Philip Maechling: okay.
Fabio Silva: what we have. If you can see my my screen.
Fabio Silva: maybe
Fabio Silva: yes, and a command line. Yeah, we're going to. We're going to start where where things begin. So so so I still mentioned. You know, there are a few of the input parameters on the broadband by from, I think we talked about using the the the alley, basing the lots of model. So that's 1 one of the things that you have to know, and the other 2 things
Fabio Silva: our
Fabio Silva: a source description, and a a list of stations for which you want to calculate those the size programs. So i'm going to use the Northridge Sars description.
Fabio Silva: which should be maybe here.
Let's see.
Fabio Silva: Yeah.
Fabio Silva: So this is the subscription that we have for
Fabio Silva: for Northridge, and just a quick, you know, overview. So magnitude is the magnitude, fault, length, and fault with the size of the the rupture plane. You know that the top is how deep the top of this plane is related to the ground. Right? And this is going to be 5 kilometers, you know. Strike, rake and deep
Fabio Silva: the laptop center, and long, long as the top center is where this plane is at the middle of it, the middle of the top. Where does that go on the surface? That's at that point, and then you know the hyper center along, strike and down tip. So remember, 0 is the middle
Fabio Silva: on the top of this plane. So you know, if you go along, strike you get positive numbers along. Strike! If you go, you know.
Fabio Silva: against right, we're gonna get negative number. So the hyperlong strike is going to be plus. In this case we have 20 kilometers, so it's going to be minus 10 to 10, and 0 is the middle
Fabio Silva: on the plan, and we I I think that the description is that i'm just walking you through this. You get a sense. Now I put down it is how down how you know
Fabio Silva: you go. Go. 19.4 kilometers down that 25 kilometer. With that you have on the plane, and I think, Rob, I let me know if i'm making any in this. This
Fabio Silva: is an assumption, but I think that's how it works with is the size of the the great size there that we're going to calculate, you know, for each one of those so that's 100 meters that we use. I don't think we'll use corner frequency for your method. That's for a different method.
Fabio Silva: The CD value there is going to be used to calculate different slip distributions, and also is going to be used to randomize the vector velocity, and also 150,
Fabio Silva: not for this case, because it's just. That's one single realization. But if you run this multiple realizations, the the programmer platform can get the hyperbolone strike and have hyper down, dip and move it about
Fabio Silva: in the rupture. Place. It kind of tests different place now, because we talk about a smaller magnitude with a smaller area that might not be. You know I I agree with you, Rob, that might not, you know, be needed. But but so this is what an Src. File looks like, and you can change those numbers that will
Fabio Silva: and see how it works. But i'm just gonna leave like this for now
Fabio Silva: the other file that we have, or we need. Here's a station list, and I have a bunch of here. I'm gonna get them. Maybe a Northridge with 3 stations somewhere.
Fabio Silva: Yeah, there's an in our
Fabio Silva: I said as well.
Fabio Silva: So I just take 3 stations out of our Northridge list the for for events. So we have, you know we station
Fabio Silva: 2,003 2,000, and 11, 2,036. So
Fabio Silva: it's, you know. Lawsuit
Fabio Silva: last to a station identifier. This can be kind of, you know
Fabio Silva: mostly anything. This is the Vs. 30 for that station that that that long
Fabio Silva: you have, that Yes, 30,
Fabio Silva: and these are, I guess if you're comparing again stateless, and this is going to be the the the range where the the the recordings that we have is useful. If you don't have that, you can omit that You don't need that.
Fabio Silva: but you can. You know you can just type this file. You can copy and paste from excel, you know, export as a text file. I I think these are his web set up. This is a tab.
Fabio Silva: No, this is a spaces. Yeah.
Fabio Silva: but a tablet work 1010, you know, 10 tabs, 10 spaces. It's not as there's you know, a a line between those that would work and rob measure. You know the hash. The pound sign here is the common percent sign is also common, but other other, that, and that is one station per line.
Fabio Silva: So so if we have this. oh, we can just run Dvp. and i'm just gonna run Vvp like that.
Fabio Silva: And and he asks you if you want to do a validation, which means, you know, comparing your you know.
Fabio Silva: calculator results against recordings that you have or not. Let's say we don't want to do that. We just want to calculate the the ground motions for the stations that you create. For example, you can do that right? Because I say no, there's not a a validation. And then we which the lost the model you want. I'm going to pick 2, which is the alley basin.
Fabio Silva: and
Fabio Silva: and then which method you want feel mentioned. There's different methods on the broadband platform. So I think we talk about the loopy method, which is a Griffith, but that that's number one.
Fabio Silva: and then
Fabio Silva: he asks you to pick a source description. You can put a P. Or you can pick one from this run folder, which is what I was thinking with. So I just leave my stuff there, so I can just do one here. And then in this all the Src files I think the one we are playing with is this
Fabio Silva: the and the north range ones I just type 8.
Robert Graves: And so fab you just
Robert Graves: i'm just thinking about in the way that Sajon will be running this
Robert Graves: so potentially he might have.
Robert Graves: I, I don't know, may may be the way to do it is. You would create
Robert Graves: a number of source descriptions that are in
Robert Graves: different directories or something. But the but this what is it? I'm trying to say? I think this is where Saj. And you you would be able to
Robert Graves: point to different Src. Descriptions
Robert Graves: that had different
Robert Graves: links are different with, you know, on on the fault right? So that's how you you You would do that change, you would edit the files outside of the platform. But then you would run the platform and point to the different ones
Fabio Silva: Right? That makes sense, and I just want to mention this is done interactively like this. So it kind of enough for him to do if you have like a 1,000 files, and there's a way to script all this. You just there's a command option that you know. He reads the script, so you don't have to type every single time. So there's a way to do to automate this, if you, if you talk about, you know large large amounts of
Robert Graves: something to to consider as we. Yeah, but it yeah. But as well mentioned, you know, right now we have this Nrg: P. 0 0. So you can copy this into a 0 0 one fire and added something, and then you can run that next time, right? So you're gonna have different results.
Fabio Silva: But that's how you know. This is the interactive way to run the platform. So we we we provided so what we we we've done so far, we to the platform that we want the Greepy method.
Fabio Silva: We want the La Basin region, and we want that source description. The only thing missing now is the station list which is asking us now, so we just say one. So let's pick one from our list, I think, because they had this one. The station of that may be number 5,
Fabio Silva: and then that's all the platform asks. You remember we just did. We just call the platform with that run Bvp.
Fabio Silva: And in this case, if you don't do anything it will compute Fps. You'll compute the Psa. You will calculate all the sessions, and it will run the site response. So you will correct
Fabio Silva: the time series to whatever vs. 30 you had for each of the stations. So the first step they already happen when it says genes, they've completed, that's the rupture generator, the after generator. It's a an Srf bio with the
Fabio Silva: with the rupture, and then i'm going to scroll back up here.
Fabio Silva: So this is the low frequency component. So Jvc. And how computes the low frequencies s programs for those 3 stations. And then, after that, you have Hf. Sims, which calculate the high frequency components. That's also done.
Fabio Silva: Match will merge the 2.
Fabio Silva: The low and high frequency will create a broadband size of a gram, and it does that for all 3 stations. We plot a map. we plot the seismograms. We compute Rogie. The Psa values. We compute Sas, and that's that takes the longest. It's about 10 s per station. There you go 12 s
Fabio Silva: and let's see here.
Fabio Silva: Yeah.
Fabio Silva: and that's the second station, and when the third station completes it will tell you where you get your stuff.
Fabio Silva: See, it's one more.
Fabio Silva: and there you go, so you can find a results there
Fabio Silva: right in this folder here. So if I want to see what's in there.
Fabio Silva: You got this phone there.
Robert Graves: and that number run number that that's Phil. You were referring to that it it creates that.
Robert Graves: and it's a unique identifier.
Robert Graves: Okay.
Robert Graves: it is there. Well, I don't know. I mean, you do. So you gotta keep track of that right. You you can change it to you, can. You can choose the number.
Robert Graves: Oh, okay.
Robert Graves: meaning that, like, you know. Maybe this is the run with the fault link that
Robert Graves: 75% of what it initially was, or something you so you could make the output run run number something that might
Robert Graves: connect to that. So you don't have to.
Robert Graves: or you don't get confused.
Fabio Silva: Yeah, I think Ultimately, probably, if you're doing all this, many runs, you probably want some kind of
Fabio Silva: table. That's how this run is this experiment that you can change that number to like, you know a 103, if you want. I don't know if that's any useful, but because you still need a table to kind of make sure that you know what 103 was, because all the files get that prefix, like all the calculated files, will get that pretty fixed. Now, this is
Philip Maechling: with the purpose of that
Philip Maechling: was so. You didn't overwrite previous results. So when you do it, One simulation we didn't want all that, you know, to lose anything you've done previously, so that
Fabio Silva: it's why that in number was introduced. But okay, yeah. So I was just gonna say that I did, I I I I run this for a second time. Let me share a different view here
Fabio Silva: which will be maybe this one.
Sajan K C: I have a quick question. Can that number be all 5 in in in a number.
Sajan K C: and we can we just change that number into, like all of it in the number, maybe like the name of the earthquake, followed by what kind of changes what we have done with the with the fault area. So then we can just keep
Fabio Silva: So right now that number is called, we call the Simulation. Id. That number has to be a number can be a small number. It could be a large number, but still has to be a some, you know, some kind of number. So I I did make a copy of that folder into. You know this web folder that we can take a look, and and
Fabio Silva: this is kind of where? What? Let's see what it's. Station map.
Chukwuebuka Nweke: Rob was indicating with the of the bookkeeping.
Chukwuebuka Nweke: This is where your book give. It becomes a significant that because
Chukwuebuka Nweke: you have those. So you have to manually essentially create this table, that relational database that says you, I indicates the number to the earthquake, to the perturbation that you made.
Chukwuebuka Nweke: And yeah, so that's what he would get. As well. Sorry about that, Bobby.
Fabio Silva: That's that's all right. My
Fabio Silva: running with the VPN. He always gets causes this trouble with this global folder.
Fabio Silva: But
Fabio Silva: I cannot click on this things. This might.
Fabio Silva: anyway. So you you get this. Let me try to do that. So
Fabio Silva: you guys have patience with the VPN. Into Usc.
Chukwuebuka Nweke: Oh, so actually crazy enough as my online Yesterday the Internet was very unstable. What you see very, very unstable.
Chukwuebuka Nweke: like my zoom calls. Were like dive in and out.
Chukwuebuka Nweke: So I I think something is going on with the campus. I don't know what's going on. Something is happening. We are in. It is just
Chukwuebuka Nweke: if you just the faculty and it it just it's
Chukwuebuka Nweke: terrible. Oh, my God, yes, it was horrible.
Fabio Silva: Yeah, I just got disconnected. I I just to the VPN. Because I don't need the weekend for this.
Fabio Silva: I get a lot of issues, you know.
Fabio Silva: frustrating.
Chukwuebuka Nweke: Yeah.
Fabio Silva: it's it. It works now. Oh, yeah. So now it works. It's just gonna be kind of thing works.
Chukwuebuka Nweke: Maybe it' be stubborn.
Fabio Silva: Let me share my screen again.
Fabio Silva: Okay.
Fabio Silva: So I get I get this yeah, zoom doesn't care if I could the VPN. Or it started again. Zoom keeps going. But that that little term in the window dive.
Fabio Silva: So, so so this is. This is the the the rupture that we did in this Northridge, and those are the 3 stations that I take randomly from our list. Just not not that they mean anything to just pick 3.
Fabio Silva: So that's that's what we just ran. And I think Rob talked about. You know the the slip distribution. So we plot
Fabio Silva: the slip distribution for this particular rupture, and that is, that relates to that seed value. So if you use a different C, you're going to have a different slip distribution on this fault, mine.
Fabio Silva: and you can see the fault plan. It's, like, you know, 25 kilometers down, and then you have 10 kilometers on this side. Thank you on that side. So the top centers here right
Robert Graves: yeah, and in the fall planes that that we'll be using are going to be a couple of kilometers, you know, dimensions, or or even less
Robert Graves: so that and that's why I was saying. I don't think the slip distribution is is gonna
Robert Graves: matter that much. It's really just the the total size.
Fabio Silva: Yeah, especially if you wanted to strength the area to kinda, you know.
Fabio Silva: like that most stress drop there. And
Robert Graves: yeah.
Fabio Silva: So so that's but you know it's there, and this is the station file and the the the source that you use. And then for each sized program, you know, there's like a simple plot showing what what came out for that particular site.
Fabio Silva: I think that's the lost in. There is a acceler of Brams, and the files are here. The Dvp files themselves. The run to 50, which is the Psa. Results for that particular station are here for the 63 periods that we do on the broadband. Platform. I think it goes from Point 0, one to 10 s.
Fabio Silva: And I we did run Fas: so we should have
Fabio Silva: a plot also for each station.
Fabio Silva: So but this is sort of like the basic phase. It's basic way of running the broadband platform. I I, as I said, the my VPN is gone, so I cannot have my little shell again, but if you run the same run, Pvp: you use a minus minus expert to call that a different mode.
Fabio Silva: Then it broadband will ask you a lot of questions. Do you want to run the side response? You want to do this one of that? So there's do you want to run the fax. Maybe you don't right. So there's different options there, and we can help you guide you through those things when time comes. But
Fabio Silva: but that's sort of like the basic way to run the broadband platform. You need to figure out what method you want with the lots of model you're going to use, which is, you know, available on the broadband, your source file and your station list, and that's
Fabio Silva: and he runs like that.
Philip Maechling: and I think that that makes sense. Very good, so I like it. Conscious of our time, we got another 8 min
Philip Maechling: to me, as far as kinda decision making on this call is.
Philip Maechling: is this useful? Should we? Is it worth going to the through the process of installing it so? And it's it in your account.
Philip Maechling: So I mean it would take an investment. I think we of your time. We'd have to have another call to get it set up, but if you think it'll be useful for your work. We're we're happy to work with you to do that.
Philip Maechling: So what what do you think? Is it?
Robert Graves: Yes. So yes, yeah. And and what? When you you you say there's an investment I I i'm not sure exactly what that means. Like it, or what? The installation!
Robert Graves: I I went through it last night, Rob, on
Philip Maechling: installing it on discovery It took
Robert Graves: 2 h in the end. Yeah. And discovery is a on the
Robert Graves: Usc. System.
Philip Maechling: A lot of it's. Well, yeah, a lot of it was transferring the files, the greens functions. So there are multiple gigabytes of and yeah, so I mean one it like 30 min waiting for this.
Philip Maechling: I'm going to see how big this file was. It's a 22 GB,
Philip Maechling: la Basin Greens function file. I I was installing everything so that means all the greens function, all the regions. So that would be to. We could reduce the time we're if you're just to in La Basin. But I did. La Basin, Nora, California, Central California, my hobby, Southern Sierra, Central Japan, Western Japan.
Philip Maechling: but for more.
Robert Graves: so that extended the time. I don't know if you need all of those
Robert Graves: A as a just to to start.
Robert Graves: maybe just do the La base, and I mean it's. You could always go back and add, add: the you know additional green function sets it. For some reason we thought that was
Robert Graves: that was important.
Philip Maechling: So I also ran the test once got installed, and
Philip Maechling: that
Philip Maechling: it also takes almost 45 min to just run the unit test to make sure everything is properly. So
Philip Maechling: okay. So. But I mean, that's the hurdle to get the basic installation. But then
Philip Maechling: it's useful. You should have everything there
Philip Maechling: I do want to express. There's, you know, where the current plan would be to
Philip Maechling: install on discovery, and that's a shared computer.
Philip Maechling: And basically
Philip Maechling: you know, when you so I don't think you see my screen. I've got an installed here. But if I
Philip Maechling: slide top type, run, Bb. This is gonna run on the headnote, and that's
Philip Maechling: you, Typically, I mean, you can get away with it, but it it's frowned upon that's there's a lot of other things. So there's when you actually are doing.
Philip Maechling: You know research with it.
Philip Maechling: What you want to do is
Philip Maechling: to do what we call the interactive
Philip Maechling: computing on compute nodes. So i'm there's it's, maybe hard to see. There's a
Philip Maechling: a command here
Philip Maechling: that you type that will
Philip Maechling: reserve move what you're running off of the head, Node, and you'll run it on a
Philip Maechling: basically a compute node.
Philip Maechling: And
Philip Maechling: so we're gonna we'll, we'll talk about that and give you instructions on how to do that. But I I just want to
Philip Maechling: give you heads up to me. This is.
Philip Maechling: we're we'll set it up on discovery. But the expectation really probably should not run on the head. Now.
Philip Maechling: Fabio, when he was running, he's basically logged into a server that dedicated server for broadband, or it does problem at development. So he didn't have that issue. But yeah for you to use of a discovery.
Philip Maechling: You You want to do this interactive computing.
Robert Graves: And so, so, Phil, when you do that as a do you get
Robert Graves: you
Robert Graves: that node just for yourself.
Robert Graves: You're not competing with anybody on that node.
Philip Maechling: I think. Yeah, that's a good question. I
Philip Maechling: schedulers typically don't divide multiple.
Philip Maechling: You know users on a particular node, but but we could check that, and we could basically request all the cpus on the on the node when we do this so.
Philip Maechling: But I just want to show. I don't know if you
Philip Maechling: so, John, if you could see. So I ran that sl like it pended it, but it it now it's granted me
Philip Maechling: time on this interactive node.
Philip Maechling: One issue is: you have to put how long you want access to that which is 2 h.
Philip Maechling: But so.
Philip Maechling: But now, if I do run Bbp.
Philip Maechling: it's running it. It. It's on the interactive.
Philip Maechling: And so i'm not running on the head notes. So I I just want to express that so.
Philip Maechling: and let I mean so. That's a kind of a little overhead. You an extra step you'll need if you will run a discovery.
Philip Maechling: If you have a server, dedicated server that you wanted to install on.
Philip Maechling: I mean, we could consider that, and you wouldn't have to do this extra step. But
Philip Maechling: since this. These nodes at the Arc are pretty capable. It's a decent place to run. So
Philip Maechling: okay, so I think I just wanted to express that that'll be so. I I mean, I think we're at the point where we're talking about setting up a maybe you know smaller group call next week to to go through this install. So it sound right.
Chukwuebuka Nweke: Yup.
Philip Maechling: Can I talk with Fabio and pick some times and send out some candidate times? Okay, okay, yeah. And and and let me just say, as as far as that that step I would say the most important participants
Robert Graves: would be Fabio, and you know, so it
Robert Graves: the rest of us, yeah.
Robert Graves: you know, could be important. But I think Fabio getting on getting installed.
Robert Graves: I think, between the 2 of them. and then presumably, we'll, we'll need some follow up after that, maybe. Again another smaller group, but with different people. Maybe it's me and sage on, and i'm telling him you know how to can, can
Robert Graves: construct source files or or something like that. One question I have is is just in in terms of the way c. Art works which I'm. I'm. Not familiar with. But is this is is there also like a
Robert Graves: a step of getting added, or has he already been added, or is, he automatically added.
Robert Graves: Yeah, we added, yeah.
Philip Maechling: we have added Sergeant to the allocation.
Philip Maechling: Okay, so. And that includes so compute time that that's one of the parameters you put in that S. Alec. You've got to put this account of what you're using, so you can use here. You can charge this, and
Philip Maechling: I mean we it's really no cost to it's our overhead. We just have to file an annual report.
Philip Maechling: but also there's Limited. There's some storage, so you can use the sk 608 for the outputs. We're
Philip Maechling: getting a little sensitive because we're like 98% full on our
Philip Maechling: storage. So if you get into.
Philip Maechling: I don't know hundreds of gigabytes.
Philip Maechling: You might need to move things around or
Robert Graves: but at this point there's you can use the stack storage.
Robert Graves: local computer, you know, and and do further analysis there.
Chukwuebuka Nweke: Yeah, if we, if we need an external storage device.
Chukwuebuka Nweke: I can purchase one of I've I've also been thinking about
Philip Maechling: buying what I think. Is it the cost of space on the on discovery? I don't know how much it costs feel.
Chukwuebuka Nweke: so I might. I might have to do it if that's if that becomes necessary for sale, and then he needs that space. And I would just I would pretty much
Robert Graves: I would register, and this rent space for sale on. When When that time comes we can do that.
Robert Graves: Saja. My. The understanding is that the
Robert Graves: the processing and analyses that you are doing, are you? You're doing that on your local computer, maybe a laptop. But it's you. You have all that software installed in whatever
Robert Graves: workflows you're using. That's all set up there. So it it would be in that sense. It's. It's more practical to transfer the data over the alternative model. Would be.
Robert Graves: You run things on discovery, or you know, and everything sits there. And then you install whatever processing software you have over there and just run everything over there. My guess is that
Robert Graves: that latter option may not be as feasible. We're not talking about. I don't think we're talking about gigabytes of data that need to be transferred back and forth.
Robert Graves: you know, maybe megabytes or something. So that doing that that transfer to the local machine. I don't think it's going to be on a risk.
Chukwuebuka Nweke: Yeah, no, I I and so I I I think the limitations here are just his machine capabilities.
Chukwuebuka Nweke: a and storage capabilities at this point. Oh, I get you. Yeah, yeah, you're right. Yeah, If If if if his laptop is one, that is, maybe it's not so, I think it's Not that it's pretty good.
Chukwuebuka Nweke: but if if it gets through, it's not stronger than I have to think about investing in the desktop for
Robert Graves: okay, and by like a workstation.
Chukwuebuka Nweke: and then get set up a workstation in in in in the lab downstairs on my office here
Chukwuebuka Nweke: where they can. I come and just go get like, use it to do work or sorry in their office. where they could essentially do some work.
Chukwuebuka Nweke: so that it but that again, when that time comes.
Robert Graves: Yeah, we can manage those situations. Yeah, we'll we can revisit. We've moved away from buying our own hardware.
Philip Maechling: So just like that server that Fabio was using that they operate it, and they rent it to us. Basically and it's cheaper than buying our own.
Chukwuebuka Nweke: It's cheap. Oh, yeah, and I've I've I've I to my friends, and they've They've indicated that that option is is probably more viable than buying.
Chukwuebuka Nweke: So what? But yeah, that's more like it. Will. That's almost like we will do by the first one. They get the business south of usage case. If we conduct in the work so we'll see how it goes.
Philip Maechling: Okay? Well, it's good.
Sajan K C: Also. You know the components. When we do the processing, we have the innovator, and we have the low frequencies, synthesis and the high frequencies, indices when you compute this size of the grand wife brings up the station.
Sajan K C: and so I wanted to know, like I read you also paid for the 2,015, the architecture on the on the bond platform, and it's, like all of these components, have been defined there. But, like what actually goes in there how the calculations are done. So I could not find what's up. The reference about the
Sajan K C: the officers innovator about the Jvs. In the we started in low frequency synthesis in hybrid, which is synthesis. So if you could just, you know, like, suggest me like I try to find papers related to those, so that, like.
Sajan K C: I would know how the calculations are being done. What is the mathematics, or what are those, you know, principles behind the computation, so that I could understand much about like what's going on there. Okay.
Philip Maechling: Good. So
Philip Maechling: I think Fabi might have a suggestion there.
Robert Graves: Well, there, yeah, yeah, Well, yeah. So I think there are some references, you know, like there's a documentation.
Robert Graves: I think. for each methodology.
Robert Graves: So so, for example, with the G. Excuse me with Gp. You know there should be some references to specific papers.
Robert Graves: Those.
Robert Graves: you know. They're all codes that I've largely written. So I, you know, have
Robert Graves: references additional references that I could provide, or even just discussion. You know I can talk with you about the the methodologies. You know what the theory is behind it.
Fabio Silva: Well, I picked it on the chat wing of the documentation for the Gp method that I have for your the latest version that I have from you, and you know the page where we find all that stuff is there
Fabio Silva: for each of the different methods on the program platform. But I think if you if you take a look at that Gp method, file the Pdf. It kind of describes sort of like, you know the the basics of I mean, it's not a comprehensive by any means, but it has links to other things.
Robert Graves: Yeah, so that's yeah, that's a good place to start. And then
Robert Graves: you know more details. You know actual journal papers, you know I can provide those it it. I think there's some references in there as well. Yeah.
Robert Graves: Yeah. So. And and I, you know I understand and appreciate where you're coming from there. You know you don't want this. Just to be some magical black box that you push some buttons, and you get a resolved. So you know that that's part of the learning process. That's great that you're interested in doing that.
Chukwuebuka Nweke: So I I, as you were saying, I I want him to kind of understand some of the mechanisms that go behind the how this is done, so that when you are primarily for the case of when he goes and presents these things.
Chukwuebuka Nweke: These are questions that they they there will be questions that are gonna be. I wanted to be familiar with these questions, so you can address those questions as
Chukwuebuka Nweke: as as necessary, so that I I I don't want to say that. Oh, it was that's how the model does it? I want it to be able to.
Robert Graves: Rob said, to do this. Yeah, yeah, I totally get it. That's that's absolutely understandable and and and expected. So
Robert Graves: yeah, we'll make sure that learn some seismology as we go along. I I appreciate. I appreciate it. You guys
Philip Maechling: very good. So we I recorded this, so i'll
Philip Maechling: post a link, or i'll send you a link out to the recording for the session. But yeah, I think this is very helpful as much.
Philip Maechling: But we did this rather than just watching the
Philip Maechling: fast download from
Chukwuebuka Nweke: Yeah. So thank you guys again, I really do appreciate it of you, Rob. Phil. Thanks so much done, and thank you, so we'll we'll wait for you, and if i'll be able to send it to you send out the the suggested dates, and then, like my Rob said, is primarily for silent and 5 here. But I make it so. I can at least see what's going on.
Philip Maechling: Okay.
Sajan K C: Very good. Thanks. Everyone.