Welcome to the 11th lecture in the course Engineering Electromagnetics. The main topic of discussion today is the transmission line parameters which are also known as the primary constants for the transmission lines. Before we take up this main topic we consider a small extension of the impedance matching on the transmission lines utilizing stub transmission lines. This impedance matching was discussed in the last lecture and we considered two possible schemes, one using a single stub and the other using a double stub and the single stub configuration can be considered to be like this and somewhere here we connect a length of a transmission line usually short circuited called the stub. The concept we consider today is the situation when the characteristic admittance of the main transmission line and of the stub transmission line are different. Now we have seen that we calculate the normalized load impedance the corresponding normalized load admittance and then we transform it up to a point where the input impedance seen looking into that plane is equal to input admittance seen is equal to 1 plus J B because the stub can only alter the imaginary portion of the admittance. Now when we are dealing with the situation when the characteristic admittances are different then let us say that the value of the susceptence that we have obtained here is 1 plus J B1 B1. The subscript 1 emphasizing the fact that this B1 is the value normalized with respect to the characteristic admittance Y1 which means that B1 is equal to the actual susceptence that is required here that is B divided by Y1 so that the actual susceptence required at this plane is B equal to B1 Y1 and therefore the normalized susceptence required on the stub transmission line is going to be B2 which is B upon Y2 the characteristic admittance of the stub transmission line alright. So when we have common characteristic impedances or common characteristic admittances then this problem does not arise if they are different then we have to recalculate the normalized susceptence corresponding to the stub transmission line characteristic value and then use this in the Smith chart alright. So this should clarify if any confusion was created earlier. Now we go on to the main topic of discussion today and that is the transmission line parameters. You would recall that we have been modeling the transmission line in the general case in the form of a distributed parameter circuit which looks like this. Each small length of the transmission line is modeled in terms of an inductance per unit length and its product with the length so L dz and then R dz and C dz and G dz and once we have modeled the transmission line in the form of this distributed parameter circuit then we have been able to calculate the propagation constant the characteristic impedance the loss etcetera alright. We shelved the question of determining these constants R L C G alright for the time being and now the time has come to discuss how one is going to calculate these constants which are also known as the primary constants. Using these primary constants the values that one gets the characteristic impedance the propagation constant those quantities become the secondary constants of the transmission line and of course once we know these primary constants then we know that we can solve the transmission line problem. We can predict its behavior or design it for various purposes. So the determination of the transmission line parameters is going to be extremely important that is the basis of the analysis of the transmission line. Before we take up the calculation of these transmission line parameters a small concept regarding the complex permittivity also needs to be introduced. The concept is best introduced by considering Ampere's law in its differential form as modified by Maxwell to include the displacement current term which reads as del cross H equal to del D by del T plus J where the term the second term on the right hand side is the conduction current term and the first term on the right hand side is the displacement current term alright. Now when we consider sinusoidally time varying signals and use phasor notation and make some simplifying assumptions which we shall discuss in a little more detail in the next lecture. We can write this as J omega epsilon E plus sigma E J equal to sigma E D equal to epsilon E the time derivative replaced by J omega alright which we can rewrite as J omega into epsilon plus sigma by J omega times the electric field or J omega times epsilon minus J sigma by omega times E and now one can conceptually say that if one replaces this term by a single term by a single symbol say the complex permittivity epsilon which has a real part and an imaginary part in particular the imaginary part being equal to sigma by omega then the right hand side can simply be written as J omega epsilon E where now this epsilon is the complex permittivity. What is the general utility of this concept? The general utility is that while in practice we are going to have lossy dielectric materials they will not be lossless analytically one could start with a lossless dielectric that is epsilon real obtain a solution which will involve epsilon in various places then if that epsilon real epsilon is replaced by the complex epsilon we will have taken into account any loss in the dielectric arising out of the finite conductivity of the dielectric material. So, the analysis for lossy dielectric materials will be simplified to that extent. So, that is how one in general utilizes the concept of complex permittivity and we are going to utilize this concept in calculating the loss in the dielectric alright. One could also say that epsilon r is epsilon r prime minus J epsilon r double prime where each quantity is divided by the free space permittivity epsilon not alright. So, having introduced these things now we can go on to the actual calculation of the transmission line parameters. Now, we require some defining relations for these parameters before we can calculate these. So, the commonly used definitions for the transmission line parameters L C R G there as follows you are familiar with these. How do we define the inductance L? Inductance L is the inductance associated with a urate length of the transmission line. And therefore, it can be obtained as the magnetic flux linkage it must be the flux linkage per unit length because we want to evaluate inductance per unit length divided by the current total current which is causing that magnetic flux alright. Similarly, one can put down the definition of the C capacitance per unit length as the total charge again per unit length not the total charge on one of the conductors of the transmission line charge per unit length divided by the voltage difference between the two conductors alright. Then the conductance G per unit length is defined as the total shunt current per unit length divided by the voltage difference between the two conductors. And finally, the resistance R per unit length would be the voltage drop per unit length divided by the total charge total current. Now, where we are just writing total current as will be clarified when we take up the illustrative example we have the series current in mind. There are two types of currents which are flowing one is the shunt current directly between the two conductors because of finite conductivity of the dielectric material. The other is the series current which is more or less uniform along the lengths of the transmission lines along the lengths of the along the lengths of the transmission line and is equal and opposite on the two conductors alright. And therefore, these this type of distinction one will have to keep in mind. We consider the example of a simple familiar transmission line and try and apply these definitions to show very clearly how these transmission line parameters can be calculated. We consider the example of a coaxial transmission line which is quite familiar to us and is quite simple also to analyze. The coaxial transmission line is composed of two conductors coaxial conductors. The cross section would look like this we can put down some coordinate system the Cartesian coordinate system. And also the cylindrical coordinate system where this becomes r and this angle is phi. The unit vector in the radial direction is this r cap and the unit vector in the phi direction is normal to this and is in the direction in which phi is increasing. And therefore, this is the phi cap direction for this particular value of phi. We can say that the radius of the inner conductor is A and the radius of the outer conductor is B and let the voltage difference between the two conductors be V naught. So, that the potential difference between the inner and the outer conductor is V naught. The inner conductor is at a higher and notionally positive voltage and the current that is flowing in the two conductors is I naught. Let us say in the z direction positive z direction in the inner conductor negative z direction in the outer conductor. This is the transmission line given to us and we attempt to calculate the transmission line parameters or the primary constants for this transmission line. We can take up the calculation of the capacitance C per unit length first and we will need the charge per unit length and in terms of that the voltage difference between the two conductors. Or in other words we need to determine the charge per unit length in terms of the potential difference or the voltage difference V naught. We start in the following manner. Let us say that Q is the charge per unit length on the inner conductor and then we apply Gauss's law to some cylinder with radius r where r has an intermediate value between a and b. So, that we get the displacement density d as Q by 2 pi r r cap. Through an application of Gauss's law we say that for r between a and b this is the displacement density vector. So, that the corresponding electric field is Q by 2 pi r and now we use the real part of the complex permittivity and say that it is again in the radial direction. Once we know the electric field of course Q is still unknown. We can determine the potential difference between the two conductors in terms of the electric field and say that V b a is minus e dot d l integral going from a to b. The potential of point b is higher with respect to the potential at point a by this amount. Therefore, it is equal to Q by 2 pi epsilon prime with a negative sign and then integral of 1 by r b r between the limits a and b giving us a value minus Q by 2 pi epsilon prime log of b by a. So, that V naught which is V a b becomes minus V b a and it is Q by 2 pi epsilon prime log of b by a. Consistent with the requirement that for a positive value of V naught Q should be positive. So, from here one can obtain a value of Q in terms of V naught, but as far as the calculation of C is concerned that is straight forward C is Q by V naught and therefore, it is twice pi epsilon prime by natural log of b by a I am sure a familiar expression. We might need a little later the value of Q in terms of V naught. So, we can write it here itself. From here Q is 2 pi epsilon prime V naught by log b by a. So that the electric field replacing Q by this new expression turns out to be V naught by r log b by a in the radial direction. Once again I am sure a familiar expression. So, we have evaluated one parameter that is the capacitance per unit length for this transmission. Now, it is available in terms of the geometry and the material that is utilized in the construction. Similarly, one can go on to the calculation of the inductance and I am afraid we will need to erase this. As far as the inductance is concerned we will have to worry about the magnetic field and the magnetic flux. For this simple geometry the magnetic field intensity between the two conductors is I naught by 2 pi r and what is the direction? Considering that I naught is in the positive z direction it can be taken to be phi cap. The corresponding magnetic flux density is going to be h multiplied by the permeability and since we normally use a dielectric material the permeability is that of the free space. But one could generalize it if necessary. Here we simply write that b is equal to mu naught h. So, it is mu naught I naught by 2 pi r once again in the phi cap direction. Now, the flux that is associated with this is going to be constant at any surface like this. No matter at what value of phi this surface is considered because of the symmetry of the problem. And therefore, one could consider any surface like this extending from a to b and in the z direction having a unit length. And calculate the total flux associated with this system total magnetic flux associated with this system. And therefore, phi which is b dot d a integral over the surface that we are considering it becomes mu naught I naught by 2 pi and then once again 1 by r d r integrated from a to b. And therefore, the value that we get is mu naught I naught by 2 pi and then log of b by a. So, that the inductance l per unit length because the flux has been calculated per unit length l which is phi by I naught is simply mu naught by 2 pi and then natural log of b by a. Some quantities of interest can be made out right here since l and c are available. The losses are usually small or if we assume that it is a lossless line then the characteristic impedance z naught which is square root of l by c can be seen to be mu naught by epsilon prime whole square root and then natural log of b by a by 2 pi. And therefore, we see that straight away in terms of the geometry and the material parameters the characteristic impedance is of a. This could have been a question that what determines the characteristic impedance of the transmission line. So, this is what determines the characteristic impedance of the transmission line. And therefore, you can design transmission lines with the required characteristic impedance right. Similarly, the phase velocity which we have seen is 1 by square root of l c comes out to be 1 by square root of mu naught epsilon prime. And depending on the real part of the relative permittivity the phase velocity will be that much different by square root of epsilon r prime compared to the free space velocity alright. Next we take up the calculation of the conductance g. If you recall the definition of the conductance g it was the total shunt current shunt current which is flowing between the two conductors directly between the in the dielectric space between the two conductors alright. That is what we have that is what we have to calculate total shunt current divided by the potential difference between the two conductors. Total shunt current let us denote it by i s is going to be the current density shunt current density j s integrated over the area through which the shunt current is flowing. Now, for this purpose one could consider some surface of radius r between the two conductors. Whatever is the total shunt current flowing through any such surface is the total shunt current through any other such surface from continuity of current alright. And therefore, this could be done at any point, but first we must identify what is j s. What is the basic cause of this shunt current? The basic cause is the shunt current is the electric field between the two conductors and the fact that the dielectric is not perfectly insulated. It has a finite conductivity and using the standard expression for the current density it is sigma times the electric field. Now, since there are two materials involved the conductor these two conductors and the dielectric both of which have some conductivity it is usually required to keep in mind what is the it is the conductivity of which material that we are talking about, but the context will make it amply clear which conductivity we have in mind. We could write a small subscript d here or when we are talking about the conductivity of the metal we could write a small subscript m there. We choose the second alternative and leave this sigma as it is understanding clearly that this is the dielectric conductivity. Now, sigma if you recall we had written as sigma by omega was epsilon prime the imaginary part of the complex permittivity and therefore, sigma is omega times epsilon prime and e is already known to us. Therefore, this current density can be put down it will turn out to be sigma which is omega epsilon prime and then v naught by r log of d by a and the direction automatically is the direction of the electric field the radial direction. Once the direction has specifically come into the expression it leaves no doubt about the nature of the shunt current. Now, this is not a function of phi in any case phi is not appearing as a parameter because the system is symmetric with respect to phi and as I said we could consider any surface. Now, what will be the surface area of that surface it will be this circumference multiplied by the unit length along the z direction. So, we need to simply multiply this by 2 pi r to get the total shunt current I s is going to be omega epsilon double prime v into 2 pi v naught by log natural log of d by a the total shunt current which flows between the two conductors. Therefore, the conductors g which is I s by v naught is simply omega epsilon prime into 2 pi by natural log of b by r log by a and one could compare the expressions for the conductance g per unit length and the capacitance c per unit length and one finds that this is simply omega epsilon double prime by epsilon prime times the capacitance c per unit length. Which relation is a general relation will hold good for transmission lines and as one can realize that both the shunt current and both the conductance and the capacitance are related to the dielectric and they are simply related through the two parts of the complex permittivity. Which parameter we have to calculate next it is the resistance r per unit length we can make some space here. Now, as far as r is concerned one could estimate the voltage drop per unit length and divide that by the total series current, but we have a simpler way out as far as the resistance is concerned since we already know the expressions in terms of which the total resistance can be obtained. In any case to estimate the voltage drop we will need that resistance per unit length. Therefore, we can straight away utilize the standard expressions for the resistance to calculate the resistance that we require here. Now, at high frequencies the calculation of resistance is complicated, but if we use the concept of skin effect the calculation can be simplified. What happens is that at high frequencies the current flows only over a limited depth in the conductors. For example, only over such a depth inside the conductor will the current be significant beyond this the current will drop to an insignificant value. This is the phenomenon of skin effect. Now, this depth within which the current flows can be calculated using the concepts of electromagnetic theory and it turns out to be 2 by omega mu sigma and now it is the metal conductivity that we talking about and therefore, we write a subscript m here. So, the skin depth is a function of the radiant frequency the permeability and the metal conductivity and one can straight away make out how this skin depth delta varies as these parameters change. This is the skin depth delta. Now, the concept of skin depth says that one could replace the entire thick metal by a thin metal the conductor which is thick which has a thickness delta equal to skin depth and assume that the current within this thickness is uniform whereas, actually in the say the infinitely thick conductor it is going to decay exponentially away from the surface. In fact, it is that phenomenon which makes the calculation of the resistance complicated, but using the concept of skin depth we simplify and we say that the actual thick metal is replaced by a thin conductor with thickness delta within which the current is assumed to be uniform over the entire surface. In which case the resistance calculation can be made very simple almost trivial. You would recall that the Ohm's law says that the resistance is equal to the resistivity rho times the length divided by the area of cross section of the entity of which we want to calculate the resistance in terms of conductivity it can be written as L by sigma A. In our case what is the conductivity? The conductivity is the metal conductivity what is L? L is the unit length along the z direction so it does not specifically enter the calculations and what is the area? Area will be this circumference multiplied by the skin depth delta. And therefore, this R comes out to be let us say if we consider the inner conductor or the resistance associated with the inner conductor it will be 1 by sigma M and then 1 upon delta into 2 pi A and of course, a similar term corresponding to the outer conductor. So, that it is 1 by sigma M delta into 2 pi B of course, assuming that the 2 conductors are made out of the same material which is going to be the practice. And therefore, it is 1 by sigma M delta into 1 by 2 pi into 1 upon delta into 2 pi A plus 1 upon B. The product sigma M delta has a value it is omega mu by what is it going to be 2 sigma M by omega mu. And it is given a new symbol 1 by R M with R M going to be omega mu by 2 sigma M whole square root and it is called the skin resistance of the material. In terms of this it is R M divided by 2 pi into 1 by A plus 1 by all right. Now, that completes the calculation of the transmission line parameters of the primary constants of the transmission line for this coaxial transmission line. Now, things were extremely simple here because of the symmetry of the transmission line symmetry of the structure, but depending on our application and our requirement we are not going to be restricted to such symmetric simple transmission lines. We are going to use any structure which serves our purpose well in which case this geometrical simplicity may not be maintained. And in such cases in such a general case it becomes difficult to apply these commonly used definitions in terms of voltage and current for these transmission line parameters. In any case we have been saying that field description is more accurate particularly at high frequencies. It so happens that for transmission lines we can still continue to use the voltage and current concepts. It is a simplified case of the general transmission structures that one uses at high frequencies. So, what would be the general definitions for these transmission line parameters which could be utilized even when the geometry is not so simple. Those general definitions will be in terms of the fields. And how do we arrive at those definitions that is the next point we consider. Field based definitions for these transmission line parameters. What would be the basis of these definitions? The basis would be either the energy stored the power loss. For example, let us consider the calculation of the capacitance based on such an energy stored definition. Then we realize that the energy stored in the capacitor in the simple situation in terms of voltage and current is half C v square. What is the corresponding expression for the energy stored in the form of the electric field? That is going to be half epsilon or epsilon prime and magnitude of e square which is the energy density. And therefore, it needs to be integrated over the volume over which the electric field is non-zero. And then we will have the energy stored in the form of the electric field. These will be the two alternative forms of the same thing. When we have sinusoidally time varying quantities voltage current electric field and magnetic field then you know that the average energy density is going to become 1 by 4 epsilon prime magnitude e square integrated over the volume. And so also will this become 1 by 4 C times magnitude of v square. And the comparison of these two terms becomes the basis for an alternative definition for the capacitance per unit length C. We can write that C is equal to epsilon prime by the V star using the phasor notation. And then within the integral we have e star d v integrated over the volume over which the electric field is non-zero. It is an alternative definition for C. It will not give us a new value for C. For example, for the structure that we just considered. And what value of C we get using this expression or in particular that we get the same value of C we will leave as an exercise. What would be the other parameters in terms of similar quantities? The L will be going through a similar argument similar procedure. It will be mu by or mu naught by i i star. If you like we could write v naught v naught star i naught i naught star. If we want to make it correspond to the example that we just considered. But that is not so important. And then here we have h dot h star where star stands for the complex conjugate of the quantity. E star is the complex conjugate of the electric field. V star is the complex conjugate of the voltage. Similarly considering the power lost in the dielectric we arrive at the following definition. It is omega epsilon double prime by v naught or v v star. And then we have within the integral E E star integrated over the cross section. Basically what we are doing is we are equating g v squared the power lost in the conductance g to the power lost in the dielectric like sigma magnitude E squared d v. Essentially that is what we are doing. Where sigma is the dielectric conductivity is equal to omega epsilon double prime. And therefore this should be quite easily acceptable. Similarly r can be written in terms of the ohmic loss or the power dissipated because of the resistance. And it will turn out to be r m by i i star where r m we have already indicated it is the skin resistance of the conducting material. And then here we have integral of h dot h star integrated over the peripheries of the conductors. And one can readily see the correspondence between this definition and the definition we have just used to calculate the resistance r. The derivation of this kind of a formula will be taken up later when we considered wave propagation in conducting medium. So this is where we will end this lecture. In today's lecture we first considered a generalization of the single stub tuner. And then we considered the calculation of the transmission line parameters which are also known as the primary constants. First using commonly used definitions and then introduce the definitions based on the fields concepts. Thank you.


I trust and what they came out and they said that there's going to be a little bit of a changes So what I want to do is bring in Jared Feldman and he is a VP of client experiences at I trust so Jared Thanks for stopping by. We appreciate it. There's a tweet that was put out said that you guys are moving and integrating with fortress trust company talk to us real quick about Who exactly Fortress is for sure And I think any sort of announcement like this begs questions and we enjoy creating transparency for our clients I have an expression that I really like and it's what would got you here Isn't necessarily going to get you there And this is a prime example of that We're going to be moving on to fortress because we see an opportunity to plug in to to more modern infrastructure, especially from a digital asset standpoint


Good afternoon hardware friends, and welcome back to the beautiful Mile High City. We're here at Supercomputing 2023. My name is Savannah Peterson, joined as usual by my co-host, John Furrier. John, I want to talk about what it was like when you were a student, because we're merging students and enterprise here. Do you think we'd be talking about this kind of stuff? Well, as a student, I was a high-performing, high-bandwidth student. I always wanted to have high-performance research. I say we're heading to the end. No, I was kind of, I will almost say it's kind of like, didn't really stand out in college. I find that hard to believe. But on that note, please welcome Dr. Lisa Perez from Texas A&M, and we've also got David Schmidt from Dell PowerEdge with us. Thank you both for being here. I can imagine it's an exciting week for you. I went by the booth seeing a bunch of different projects you have for a variety of different ages that you're both collaborating on. I think the easiest place to start is to start with the ACES project, since it's a bit of a halo for all of that. Dr. Perez, can you tell the audience a little bit about that? So the ACES project is something that we envision to support researchers across all of the different disciplines, but with a focus on AIML. Since, you know, very emerging, you know, we need a lot of resources for it, and the researchers have a wide variety of needs, especially in their hardware, for the different types of AIML, and the ever-quickly-changing needs for AIML. So we partnered with Dell, and Dell provided us with support and information about different resources, different other industry partners that we could connect with, and bring together this beautiful ACES system. So ACES is a system that has hardware composability. Okay, so it's composability at the hardware level. So very different from virtualization, whereas with the virtualization composability, you're looking at taking a resource and cutting it into smaller pieces and providing the smaller pieces. The hardware composability, you're taking disaggregated resources and bringing them together, composing them onto the compute node to make a larger resource to support those AIML and HPC workflows. So that is the ACES system in a nutshell. That was perfect.  I got to ask you, what does that enable? Because this is the big conversation here, as Savannah mentioned, disaggregation, silicon diversity, HPC plus AI, which has got performance and intelligence and inference training. What's going to come out of that? Because I'm imagining this is going to get more flexibility on how to deploy use cases, maybe, and or performance. So you're going to get performance and agility. What are some of the benefits? Can you share some anecdotes or stories around what comes out of that? So you can take a common AI ML workflow, take PyTorch, I'm for whatever your research needs are. And programming and looking at IML models, when you have your GPUs directly or whatever accelerator directly on the compute node, that programming model is reasonably simple. If you run out of resources and you have to move off node and to another node, then it gets far more complicated. So having the ability to have that hardware composability to take those compute resources and bring them to the node. So we have the Dell R760s, we have a variety of GPUs, we have some of the NVIDIA GPUs, Intel GPUs, composing those to the compute nodes is what allows for a simplified software model. And that's what enables the researchers. And then they can grab whatever accelerator they need that's available in the pool, compose it to the node and that enables them for their research. It's easier for them too, they get the software advantage, you guys provide the bare metal and the composability. That's right and it really changes the conversation talking to Dr. Perez and her team from what research can I get done on my infrastructure to what research do I need to get done and then go find the resources. So you're no longer bound by any one instance of a system, any one particular deployment. I think Dr. Perez was telling me that the deployments last are stretching back over a couple of different generations and you're able to utilize the latest and just add it on to the platform. And so we very much focus on these types of use cases and understanding what it means for the future because we know that we're not going to stop here, we're not going to stop with the hardware and the different types of accelerators and CPUs, our roadmap's going to keep growing. And so we're really focused on how do we enable projects like this in the future. We love to hear it and you touched on something that I think is really relevant right now as we're talking about quantum, our whole future in general, we're thinking about not just the questions we've asked before or being, to your point, infrastructure bound by our capabilities, but saying not just what research can I do, what solutions could we invent? What could happen now? I think it's actually going to revolutionize our thinking and it's so exciting that you're working at the intersection on this together. Dr. Perez, I have to say I went by the A&M booth, which I encourage y'all to do if you're here or figure out on video, or we'll look on their website, I should say rather. There are so many different interesting projects that folks are doing within your community. Everything from recruiting more K through 12 STEM teachers to predicting the sonic booms to also sequencing our genome. What are you doing perhaps collectively to recruit these types of projects? How are you fostering them up through the ecosystem so people can realize this? So I would have to say the number one reason why we've been able to provide that support for all of those different disciplines is the way that we present the hardware. We build out additions to the Open On Demand portal, which makes it very easy for the users to come in and utilize this very complicated hardware. We provide a large and diverse set of training and short courses, and we provide them to the national community. And our goal in those is not to just lecture. We immediately come in and say, here's an introduction to what you can do, and now let's do it. And so we get them on the system and doing practical application on the system. And we never say, okay, well, you have to be in this category or this category. It's a let's get everybody across the board down to the high school level, down to the junior high level. The teacher's so important because we need to get them early and bring them up in the ecosystem. But that portal that makes it easy to get access is critical. To make that portal work, it's got to be easy. Yes. You got to hide all the complexity. Yes. Okay, under the hood. What's the secret to that? Is it just design? Is it, how do other people do this? Because this is the topic here. We're hearing this as a big part of it in every single supercomputer area. So I would have to say, from what I've seen, our group, the high performance research computing group at Texas A&M, we have a very good group of staff members, research scientists, the executive director, Hong-Gao Liu. It's the design, but more importantly, understanding the researcher. So our staff really looks at the holistic view and understands the need of the researcher that doesn't necessarily understand the underlying HPC. And that right there, you just hit on what will, and people love to use terms like this. I hate being one of those people, but I'm going to do it right now. That will be the pivot point for the paradigm shift. It's when exactly what you're talking about is kind of this intel inside, but the laptop just works. When the hardware and the software are working for the researcher to say, I want to go cure cancer. I want to go solve this problem. It's just going to work like me going to Google.com. I mean, that's an amazingly liberating thing when you think about, the term gets thrown around a lot, saying democratizing, I don't know that it's democracy, there's definitely still a bit of the haves and have nots, but that accessibility and that user experience, which we don't talk about enough, there's a lot of educational barrier between first-time folks and those going out there. Dr. Perez, I want to stay with you just for a second because I know that you're a teacher yourself, that you also do a lot of recruitment, and that you work with a variety of different ages. What would you tell or what are you telling rather, young people or anyone, I would say folks who might be more green in this space. I hate the age discrimination, that's not even going down that path. What would you, how would you welcome newbies to our little lovely nerdy world right now? What's been your tactic? And David, I'm curious if you have an answer on this too. I want to hear Dr. Perez's answer for that. Yeah, exactly. So my approach normally is I don't really, I just introduce them to the resources, and I don't really focus on, this is HBC and this is that. It's like, this is what you can do with it. And I give the introduction that way, and I feel that that tends to bring them into the fold easier because then they can start thinking about, oh, what can I do? What can I do? Instead of worrying about, oh, this is hard, this is hard, right? So, yeah, so that's my general approach. And the scary words can scare them off in itself. Yes, yeah. I have to, I have to go ahead. Well, I was going to say, I think, you know, maybe pushing Dr. Perez a little bit more here as well, that coming up early, you know, over the weekend, when we all got here, well, you guys may have gotten here a little bit earlier, but coming up here on a Friday to spend time with the undergraduates, making sure that that level of, I know, yeah, I mean. That's the best, so I'm super partial to the students. I love adults, you're all lovely, but they're the best. And I think those are the things, and then building the right technical environment so that they can learn and learn easily and not have it so scary. Yes, what you said earlier about, it should all just work, but we all know it's easier said than done, and it takes partnerships, it takes an ecosystem, and it takes kind of working on those things and kind of pushing through the barriers to get those things done, and that's what I love the most about this particular project with ACEs and everything else that the team has done at Texas A&M, is they've made it happen, and now they get to do really fun things, like spend a weekend in Denver with undergraduates, so. And I think the democratization, whatever word you want to use, but opens up more collaboration. Okay, if they have access easily to the resources, and again, we are big believers in proponents of more collaboration, more openness creates more value, and diversity value as well. So how do you guys see this composability at the hardware level changing the research landscape because when you have people coming in, processing technology, people process technologies that the transformation equation, okay, more people are coming in. The processes are changing because AI workflows are a little bit different. The needs of the researchers are changing, maybe they're coming in at all levels of the spectrum. What's the impact to the composability of the hardware from a research landscape perspective? You know, I think being able to incorporate the new things that are coming along, like you said, but you also said a keyword with infrastructure, and to me, that means standards. And if you think about the new things that are coming, you think about what's out there. It's a super important conversation. We're going to see some really interesting footprints over all sizes, and we're talking about power, cooling, overall laws of physics, where our next generation of infrastructure is going to be pretty interesting to see because we're going to want to enable very large-scale training instances. We're going to want to enable inferencing at different parts of our different environments, different use cases. And so how we make sure that that's all standards driven and that we're not asking researchers like Dr. Perez to cobble together a bunch of things on their own, that's super important to us right now. And we think that kind of accelerates, man, sorry for the pun, but we think it kind of accelerates the ability to build these solutions in the future when there is that kind of next generation or next two generations of clusters or projects that we have to build. Maybe the word cobble together is going to be no longer in the vocabulary if this continues to have opposable infrastructure, right? No one wants to cobble anything together. I think of heavy lifting, mundane tasks, provisioning. Well, and the tools are going to be moving around a lot.  If there's not a universal setting like we've seen with dongles, just as an example, between micro USB, USB-C, my gosh, we're all sick of it. If there's not a standard, it actually impedes not only the hardware, but the software development that everybody gets to collab with. David, I want to go to you with my next question. SC-22 was a big year for Dell. It was. Some absolutely massive beast announcements, which were very exciting. That's right. We've had a lot of y'all on the show this time around. We love to hear it. I'm curious, what are we going to be talking about next year? That you're allowed to tell us. I understand this a little. I know, right, if I told you, would you? We would promote it and be charming and help recruit more researchers and more developers and more engineers for your team. We are really looking forward. If you look at what we've been talking about in as far as AI solutions, generative AI solutions, helping enterprises just to branch out a little bit for a moment, helping enterprises deliver large language models on-prem. We are super focused on those things. So we are interested in making it easier, but when I think about the infrastructure, the stuff that you really geek out on at Super Compute, you're going to see some really interesting things from Dell and our partners. You're going to see some interesting things in terms of how we bring different solutions to market, different capabilities in all gamuts, they're all spectrum, I guess, of AI. And I would probably leave it there because I can't take all the good copy a year in advance, but I'm super excited about it. It's exciting. We were having our conversation just yesterday with the team about all the great stuff we're going to be talking about because it really is going to be about the next generation of AI and computing in general. Well, my only last question, Dr. Perez, for you guys, the last minute we have left, put a plug-in for your groups, what are you working on? What accomplishments are you proud of? The things you would like people to know, put a quick commercial in for your group. I would have to say that it's our outreach and the way that we provide the hardware. So our interfaces where we make it easy for the user to come in and set up a job and submit it with having very little HPC experience, we want them to focus on their research. So that is our main goal, so we want to provide these wonderful resources for the entire HPC spectrum with the new and novel resources that are coming up in the AI ML field. And we want to let the researcher use it without having to think about it. David, plug-in for PowerEdge, powering all this, what's on the roadmap, what's coming around the corner, what's this hardware matters? We're really, you talked about having a really awesome set of purpose-built AI products last year and we are still enjoying that conversation with our customers and enabling our customers. I mean, as well you should be in fairness. Yeah. We're, it is a lot of fun right now and I think the possibilities are just huge. And when you think about the next generation of infrastructure and you think about our ability to drive standards into the market so that this is easier to adopt and build the right platforms for the right use cases, it's going to be super exciting. We will continue to do what we do with PowerEdge is make sure we've got the right testing and validation and capabilities and design points in the hardware so that when it's time to build the next aces, we're there and we're ready to do it with the right partners and the right capabilities. So. Get that hardware in there so they can compose down to the hardware level. We really look forward to hearing about the continued projects that come out of your collaboration and all that lies ahead. David Schmidt with Dell PowerEdge. Thank you so much for being here. Dr. Lisa Perez, Texas A&M. Thank you for what you do inspiring the existing and next generation of folks who are going to shape our future. John, thanks for always being entertaining and fun to share many days. I'll show you my college transcript if you're interested. Nevermind. I don't know what we need to say. If we're going to say anything, I'm going to go ahead and say, welcome to the Washington Huskies, proud UW alum, number five in the nation right now in football. You are watching Supercomputing 2023 here live from Denver, Colorado. My name's Savannah Peterson. Thank you for tuning into theCUBE, the leading source for technology coverage.


For those who don't know, we are right next to a statue right now in this building. It is between the main library and the Asian Art Museum. Let me see if I can figure out what the directions are. I think it's that way. I think that's right. That way? Something like that. Anyway, a prone native man being menaced by a vaquero and a priest, we decided maybe it was time to get rid of that bit of legacy furniture. Everybody's got some, right? You end up inheriting some stuff from the parents or the grandparents that's emotionally fraught and weighted and is also just not going with anything you want to say about the way you live. Sometimes you've got to store that stuff. So I'm now looking for that file, which I know is in here. Here we are. I decided after the Board of Appeals and Entitlements, you can't write it, can you? The Board of Appeals and Entitlements in the city decided that the Arts Commission, who technically owns the statue, and the Historical Preservation Society, who has control over taking things like that down, didn't get to decide that so they put a stay on the removal. And I wrote a poem every day between that and the time they decided to re-hear that case. There are 55 of them, but I'm not going to read them all. Yes, it is early days. For the Appeal Board, who decided on April 18, 2018 that the early days statue should stay in the San Francisco Civic Center. San Francisco is a sanctuary city, but reminds my sons to cower.  San Francisco panned out of mud and water, now curls in mythology, seductive and moral on the Bay Shore, and smiling, wears a diamond necklace of Winning the West down Market Street. If you will not kneel, you will be kneeled. If you will not submit, you will be cast in bronze, submitted. Our skins are still traded in for treasure at City Hall in San Francisco. The second early day. For over 500 years, we are asked to die. We are put in a position to die. We are actively killed. Mis-history, done person, delanguage. Keep talking, everyone learns something. Keep laughing. There aren't enough of you to fill a comic book. Humane treatment is a numbers game San Francisco's Board of Entitlement assures us. The third early day. Civic art helps to establish community value, sometimes the value is cultural supremacy. Less thought has been given to removing this statue than to removing a window when a statue is a window. A symbol, a call to arms when a statue is a window into a tradition of erasure and abuse. When a statue is a celebration of the cleverness of theft, the braveness of armed invasion, the nobility of enslaving others, the nobility of celebrating it. The fourth early day. I have to tell you I got really cranky by the 55th early day. I was so angry. The fourth early day. A statue is not a library, it's not a book, but if it were low income housing it'd be gone by now. Removing a statue is not burning a book with or without the statue we will remember and you have already forgotten. The fifth early day. Taking down a statue isn't genocide anymore than removing a building as genocide and how many buildings have been raised in the last three years. How many buildings over 50 years old? How many tent cities? How many people over 50, their histories thrown into trash trucks? Sweep, they call it. Don't touch the bronze casting, the metal that doesn't bleed, the metal that isn't hunted back to its village and dragged to a mission for forced labor. The culture of statues is safe. The sixth early day. Civic statues, it is said, are not fully understood by the Arts Commission artists but are by someone descended from museum owners. Museums. Cabinets of curiosity. Collections of relics. Loot of the ages. As if control were understanding. As if owning was understanding. As if a statue were a kidnapped woman or a flayed skin. Civic statues convey honor on events or people, commemorate, establish the values of the community. What stands in our Civic Center in San Francisco? What does San Francisco stand for? The seventh early day. Twenty-one missions from San Diego to Sonoma. Cenotaphs with rounded numbers of those worked to death, alienated to death. The Catholics kept good notes. But these relics mythologized colonization by a medallion at the gift shop. You won't find one with an image of the Cenotaph with the numbers of our beloved dead. Nearby strip malls, wineries, missions style. But San Francisco feels that there are too few reminders. The eighth early day. And this is going to be the last of this series because I start getting really irritated. If civic art was simply a matter of art, we could have this discussion. If people deciding how other people were represented was simply a matter of self-expression, we could talk over my kitchen table into the small hours. We could laugh and compare and opine. If a small group of people not including any representatives of another group are deciding how that group are seen by every tourist and visiting dignitary one of the most storied cities in the western hemisphere. A group that is still colonized whose members are still habitually raped at a rate more than twice the national average. Whose young people see so little hope that the teen suicide rates are described as at crisis levels. Then this is not a discussion about art because you're not just deciding on a sculpture. You're deciding our worth. This is a petty exercise of power and you have leashed your reputations to that story and that statue. Fifty-five whole days. Doug would come downstairs and see me going at my computer screen as I was making sure I had the details of California history correct because although I am indigenous I am not a California indigenous person. I am an indigenous person who lives in California and I owed it to the people who host me in this place not to get it wrong. You are more than welcome sis. So as long as we've gone down this road this is a little lighter but not a whole lot. It's called the butterfly war and if you don't know about it look up the Mariposa war. The butterfly war never ended. This tension and the seers keep burning flame pressing tips into each hidden place that Tanaya knew and the fires pass the people. Scatter seed. Scatter seed to hold the earth down to hold it down in the valley in Mariposa Grove. There is a fire and it reads the stories of these hills out loud in voices too terrible, too airless for understanding. It takes the trees by the throat and reads them ring by ring into the finger holds that water has and the beating of indefinable wings of flame. These winds of burning take non-human prayers to other gods on that smoke and every bit of hope in history is told and retold in cracked rock and charcoal stands of trees. Oh that's okay. I guess I did it to you didn't I Linda? Once upon a time I used to tell people that if they didn't applaud I'd pout. We are in day eight, day eight of nine straight days performing and I'm like yeah yeah okay applause whatever. It's horrible but people keep asking me what the laureate position is like what the job is and what it does and much of what it's done for me is that I am almost entirely self-contained as a poet now which is not what I would have predicted. At the same time I am almost never by myself. This is called safest houses. Houses are a matter of faith. We sat once over the reservoir there's a parking lot there.  We were heading to a house, a trusted thing that had been carefully preserved with cats and computers and paintings intact past waterfalls which I should maybe have grown out of by now but still that long drop the freedom of water tossing itself off of hillsides the bravery of water the odd safety of houses made of wood and the idea the sacrifice trees just visible from the road an amulet underfoot. Navigation. It's hard to tell if this is fog or prayer smoke and the singing of flowers and horns already in some places these poems whispering into snakes some dissolving going who knows where or falling into the dark of buried mirrors. Try to dream the things that your rebuena plants dream when the new printed storm runs fingers through the cypress and reaches along hidden routes and quiet water songs in the cracks in the serpentine. They find salamander prayers in layered stone coins lost in the fret of post earthquake with slumped brick and the full panic of witness and dynamite. These hills hold down hold down and breathe storm and smile up into the rain eyes and change again. Cusp. Morningstar. The redwood has caught her for the moment this ancestor net a cold game on the cusp of a day that I know will be hot will bake the tiny tomatoes on the vine and set lavender and rosemary free ripples of early autumn that break out in orange butterflies. Contraband. There is no need to forbid the songs on a Monday morning with the cold shivering the lights near the mint and the braced gray buildings with their red blinking signals to airplanes. Beware. I think of a fortress as an old fashioned thing and in a way it is, but we're not singing and the barricades are up in some pretense of offence and the boats are in the bay and the songs are not being sung although we are allowed and revolution is a T or a jacket and doesn't lend support and still the street lights are trembling as the woman under them does not and we will measure her worthiness for help her parents and her choices the mess and bold fact of her there and she isn't singing either not soup or poem no song of any kind. How many people lived in California during the drought in the 70s? I know there are three of us. None of the fountains ran. They were all empty. Panic is a luxury for those who are only in danger seasonally. Relax between the battles. Some people don't want your help don't want you in the neighborhood they have chosen from a catalog. There is a heat that only comes from these sidewalks and nowhere else. I can only sleep with my head on the shoulder of a cousin these days. Parallels I understand. You explain to me what's safe away from this kitchen table. The texture and quality of your words we weave the weaving time is here sift pull edit manage stand with me now in the ceremony of living by breathing water the rain is coming. Relax between battles smile or help there is a heat that only comes from these sidewalks what's safe weaving time is here manage the rain is coming underfoot and sidewalk among the tall ships wrapped tight in the earth now northeast towards the recreated waterfront a teacup full of atmosphere charming historical and the singer holds the mic so you can sing along we all know all of the words fog horn signal so that you can avoid bumping into people their tents on the sidewalk and unsightly need that could make you feel almost human these ships remember ocean tight quarters sweat and sway some days they tremble writing waves of imagination we made believe we made real these bricks as solid as anything things being what they are could burst into moths or shrouded restaurant tables in narrow streets a palm full of seeds that every newcomer thinks they've discovered I myself have been discovered in every decade of my life try not to break too many dreams on the rocks or the tent poles it can take a moment to get your footing I'm going to read this you know I say this regularly but when you write a really political poem about something very specific you hope that you stop having to read it at some point unfortunately please tell my family I'm alive it's hard to know where we are with everything broken and scattered war and weather will do that and there's weather to come we need to decide what we all understand and what's local survived like a single tea cup it's always strange what's spared and what's taken the chair has come apart and roof pieces are mixed in with spilled sugar but that horrible quilt of your mother's is okay storm sound has marked me and I'll never stop hearing it shocking now the idea safe as houses and we did feel safe we did pull our ideas around us like wooden walls and we thought we knew coming down into Eureka valley this hillside remembers being wild and the trees still talk about the orchard that replaced purple bunch grass and rattlesnake the arroyo salamanders coil under ceramic pots and sing songs about wet years under the bay white roses grow from rootstock after the grafts failed and the bearded iris bolted every ten years or so saffron crocus bloom under the Maribel plums looking for something this okay I'm going to do three more I am another who the ground swallows whole I am another who the ground swallows whole who learned to walk an expectation from you I am one who writes long-winded goodbyes knowing where the escape hatch is and not pulling the handle that our limbic systems are on overload and we can always smell the summer south with all of the ripe and rot and bloom for me the stars are never the same number twice no matter how carefully I count and now without the other pointing finger surely not that the starlight is a memory and may twinkle in or out and there are these rooms and houses that we can describe and visit but still we know only the names are changed only the names so if I say Norma Jean who do you think I'm talking about Marilyn Monroe this is a different Norma Jean this is Norma Jean Croy who is a political prisoner in California another native Californian an indigenous Californian native Californian from here out here when Norma Jean was in prison witnessed to a thing declared not to have happened accomplished to nothing and shot in the back the ceremonies continued and sacred caves were subject to gradual water I've been seduced by water and this slides palms over a place I would otherwise stand in a place I have stood in wearing sandals water to my knees and prayed child thoughts into the listening ears of water sank a small hand like Sirius into the silt to find the next unfired shell I let that bullet rest there between life and heart and fate lines and stared at such an expensive thing turned to water that licks the leftover caves of lead mines metal finding its level and later after Norma Jean's lovers have run similar hands over the scar just there on my own back luckily placed where there was no threat to spine or lung if their hands were clever they found it brass unstamped and some have left it and some have temporarily pulled it from my flesh and curiosity no way to explain what we hold on to no way to explain how we carry our fears this is a poem I seriously hope that I don't have to read for very long it's called parent and child cycle one when the first pain hit I went up on my toes birth dances you and all of the people that will breathe at you speaking for myself they were of no help we did that dance together my son and I became two people it's another kind of storytelling two we took the stereotypes in our hands and tore them up the worlds we've created between us parent and child person and person you curled there and whispered stories of healing into my fever dreams that have adventured three cleaning grandpa's desk we found the Mary of Shestahova her black skin rendered in silver metal ISIS by any other name still brought her lover back from the dead and claimed a son from him ISIS of sky and wisdom wrapped in blue as I have been just feeling the heartbeat the damp skin the wonder of a new person four we carefully mark the places where the world changes pack our borders, our toothbrushes walking shoes rewritten in every watershed every story shed children of corn walking north the sons of corn perform the magic as they were taught and the people were fed we are dusted with pollen we are walking north five the child shows me the mark of the scorpion on his leg I show him the mark of the spider on mine we have walked dangerous miles he and I separate parts of the same story the gods took a handful of cornflower, some blood and we are born danced, went up on our toes you may have been born differently but this is our story six children in cages dys prayer and genetic memory offers a panic stolen children the sacred geometry shattered we carry our borders we who are blood and corn we reach across rivers we call our cousins we burn the copal seven this part of the story isn't written yet we are all going to have to write it together thank you