So today we will talk about spray combustion this is actually like a follow-up to the droplet combustion that we did where we were basically considering only a single droplet at a time and at the time I pointed out that it may or may not be exactly the way it happens in reality because in reality you may have a cloud of droplets that burn or you may have all the droplets evaporate by the time they reach a gas phase frame and therefore we do not necessarily have a droplet combustion and so on. So there are lots of different possibilities and it also depends on whether the spray is dense or dilute and typically we think about a single droplet combustion mode in a spray in reality most of the droplet combustion happens only in sprays right so spray is the more realistic situation that we need to think about and the single droplet combustion mode probably happens only in the in situations where you have dilute sprays and so on. So let us now see if we can take take the idea of the single droplet combustion further and see when that happens in a spray so basically we will now look at spray combustion now there are a couple of ways by which you can think about spray combustion similar to the way we have been dealing with the gas phase flames so in the case of gas phase flames we had on the one hand premixed flames on the other hand we had the diffusion flames right so we could think about these things as we could still think about like analogies to spray combustion similarly but however we have to think about in reality it is again in between it is not it is neither premixed nor diffusion so what is really meant by a premixed spray combustion or what is meant by a diffusion flame kind of spray combustion on the one hand you could now think about droplets that are now laden in an oxidizing gaseous flow gaseous oxidizing flow so if it is possible for us to mix liquid droplets of fuel in a gaseous oxidizing flow and of course the gaseous oxidizing flow could also have inert gases like for example if you are looking at a gasoline air mixture or something like that right so air has the oxidizing gaseous species as well as inert gaseous species and then you are now throwing in liquid droplets of gasoline and then let us suppose that you now have the flow up here flow in a tube and then you now stabilize the flame in between or you could also think about more like a Bunsen burner where you have the approach flow is actually made of the a mixture of liquid droplets in a gaseous oxidizing flow so that is that is one one configuration that you can think about on the other hand let us suppose that you now just have an orifice in which through which you just issue a liquid fuel and because the orifice is so small or the pressure injection pressure is high or a combination of both you now have a spray that is coming out so what is basically coming out is essentially a liquid fuel spray and the oxygen has to get in the oxidizer is in the ambience and it has to get entrained into this and as it gets entrained it mixes vaporizes the liquid and burns the liquid fuel and so on so that that would be like a diffusion flame counterpart in reality as I said you would have a combination of these two things it is neither this nor that and of course you can think about like a partially premixed flame that is established in a in what could be nominally a non premixed injection of liquid fuel but you since you have like a standoff distance it allows for some mixing and so on so many such possibilities exist in reality so what we will first consider is a premixed mixture force for the sake of simplicity mixture of liquid fuel droplets and oxidizing gish is oxidizing gish is oxidizer plus inert or diluent right. So as I said you could have like a possibilities or let us say you have a tube and then you have now the reactants and then you have a flame and then you have products or you could have a burner in which you now send the reactants and then you have a flame and then of course you have products downstream of the flame. So these are different possibilities in this case for example you now can talk about talk about a SL and what is really opposing it is the normal component of the flow right. So that is equivalent to saying you now have a reactant flow at the speed of SL that is approaching a stationary flame or in a flame fixed coordinate system. So in this case what we are basically talking about is let us suppose that in if you now look at this locally or in this region what this basically amounts to is if you now have a flame right what you are essentially saying is you now have a droplet that is approaching the flame along with oxidizing gas with inert and then it begins to evaporate because it is now in the influence of the flame as far as the heating is concerned and as the heating happens you now sorry as the evaporating happens it not the fuel vapor is now evaporating out and then also flowing along with the oxidizing gas and mixes and you now reach this is the flame and when this liquid droplet goes past it you now still have a liquid droplet with a flame behind around it as an envelope flame and this now decreases further into a smaller droplet and then flame and so on. So this is typically the kind of picture that we are looking at in these situations alright so if it is possible for us to now set up something like a Bunsen burner with liquid fuel droplets we should now expect the larger ones particularly and that is what I am just next going to talk about the larger ones will actually get you start burning as they flow through the flame and then begin to go as individual droplets that are burning not like in single droplet combustion that we have seen but the smaller ones will now have evaporated by the time they reach the flame therefore you would not have a single droplet combustion right. So the question that we have to ask is what is the limiting droplet size below which below which you will not have a single droplet combustion mode okay so if this droplet is going to actually shrink to 0 size by the time it reaches the flame that means starting size should have been small enough if it is large then it keeps on shrinking but when it gets past it begins to burn in a single droplet mode right. So the question basically is what is the limiting size below which the droplets do not burn in a single droplet mode the answer to that question can be done by a simple analysis. So the thing that we look at is what is the residence time of the droplet in the flame right so the so what we are basically saying is sufficiently small droplets or completely vaporized vaporized in the preheat zone the preheat zone of the flame is where the heat conduction is happening so the characteristic time the characteristic time of traversing through the preheat zone preheat zone is let us say Tau D is LD which is like the flame thickness divided by SL and that would be K divided by CP rho G divided by we should have actually at LD is K divided by CP rho G SL and we also have another SL before you get a SL squared and then what we have to compare this time is with the droplet evaporation time how long does it take for the droplet to evaporate versus how long is it going to be within the preheat zone right so the droplet vaporization time time is Tau V is Dl0 square divided by 4k that is essentially is into talking about the radius divided by the in terms of surface area divided by the evaporation constant it is essentially coming from the D square law and so this is this is as if this is D square law for evaporation we are not basically saying that it is going to burn in a single droplet mode but we talked about when we did see single droplets we also said that the same approach can hold good for evaporation so then we use the expression for the evaporation constant that we had obtained to get natural logarithm 1 plus B where B is now K CP T infinity minus T B the boiling point divided by the latent heat of vaporization so if you now say that these two times are comparable then we begin to get a diameter of the droplet below which you would not have a single droplet combustion that means you would not have anything that is burning and coming out of the flame right so for Tau D approximately equal to Tau V or the same order Dl0 min square equals 8 rho G by rho L K over CP divided by rho G SL the whole square natural logarithm 1 plus B the reason why we write rho G SL together is this is actually the mass burning rate or the burning mass burning mass flux okay so now for typical values of things like if you now assume approximately stoichiometric mixture for the fuel and air where the combustion happens and then you now throw in like row L over rho G is of the order of 1000 and then and so on so you do all these things then so this gives about 10 microns so Dl minimum Dl0 that is the original droplet size the minimum original droplet size is of the order of 10 microns 10 micrometers for typical values for other quantities right now we can also see the dependency here so for rho G SL squared of the all going as going a speed of the N you know it is coming from how the the burning velocity depends on the pressure and we are looking at rho G SL the whole square so we remember that and we say it is going a speed of the N then then D L0 minimum squared goes as p to the 1-n right and this is purely coming so what this means is the pressure dependence purely comes from the preheat zone length okay and we do not have to worry about the dependence of the evaporation time on the pressure so the evaporation time is not dependent on pressure it is only the preheat same length that changes with pressure and therefore the residence time of the droplet within the preheat zone is going to change like this right so that is mainly the effect on of pressure what we should actually look for and you now have these bunch of droplets here so we the picture that we drew is only for one droplet right but that is not that is not reality so this is assuming like a dilute spray essentially and then talking about a single droplet combustion event in the case of droplets of size larger than the D minimum right so question is what is the interaction effect okay so the droplet interaction now assume assume for for this purpose equal size of droplets right then what you essentially saying is let us suppose that these droplets are located in space at a particular time with some distance and what we would like to think is the distances are about the same okay for the sake of what we are doing not we are not very difficult we are basically looking for something like an average inter droplet distance so what you could then do is now draw spheres around these and so on and if you now say this is this this the sphere around which you around the droplet that you have drawn is having a diameter that is equal to the that is approximately equal to the inter droplet distance okay and then if you now take that sphere worth of mass of oxidizer neglecting the presence of the droplet okay and then take the mass of the droplet you can now form a fuel mixture based on that alright now we are there are voids here and those volumes of the oxidizer we are not considering so it kind of compensates between taking this volume and not taking that volume right so approximately speaking the the fueler ratio the fueler ratio is F over a is approximately 1 over 6 pi DL cubed rho L it is essentially 4 over 3 pi RL cubed but RL DL is RL divided by 2 sorry RL is DL divided by 2 so if you now plug that in there you get the 1 over 6 DG cubed rho G so the DG that we are talking about is the inter droplet distance average okay so DG average inter droplet distance right so what does that mean this is like row row L over rho G times DL over DG the whole cubed so what this means is of course if you have for nearly stoichiometric mixture stoichiometric combustion for typical hydrocarbons let us say typical liquid hydrocarbons your F over a should be around 0.05 all right you can you can evaluate that for typical so you look at the stoichiometric chemical reaction and the pins balanced and then you can look at the mass ratios for that if you now plug that in and row L over rho G is about 10 to the 3 right then we can we can find that DG over DL is of the order of 25 right so 25 is like more than 10 so we can say that the inter droplet distance is about is quite larger when compared to the droplet diameter itself so this does not mean too much interaction but if you now start thinking about the effective pressure okay so at high pressures rho G increases okay because as pressure increases rho G increases so if row L over rho G so if if rho G increases low L over rho G decreases if row L over rho G decreases then DL over DG DG will increase or DG will decrease effectively right so DG over DL then DL decreases for example in automobile engines if you now look at the typical kind of pressures you will find that those pressures DG by DL would be as lower like about 15 or something is still around greater than 10 but you are now hitting a limit where you have to consider the interactions what we should then start to think about as we started looking at a premixed mixture but let us now look at a jet jet a spray jet and a spray jet flame so this is now getting closer to reality so what is going on here is the two things one as you now have a jet that is coming out this is jet of liquid fuel it is also beginning to entrain air and then of course we have ignited it then there is a flame the question is are we having individual droplets that are burning in this flame or is it like an envelope of the all the droplets that is burning together that is essentially the question that we have to ask right so the answer to that is of course the droplets are evaporating from the heat of the flames right so the competition now is between how much is the entrainment right because you need the oxidizer for the flame to happen and so therefore you need to have the entrainment to happen so how fast is the entrainment versus how fast is the evaporation so the evaporation is going to give rise to the fuel the gaseous fuel the entrainment is going to bring in the great gaseous oxidizer and you need to have both of these for the combustion to happen right so typically when you are now looking at entrainment the entrainment is happening from the sides and then it starts penetrating to the core so there is a there is a core of liquid which does not see the ambient air significantly right for some distance may be on which the ambience penetrates so you could now think about the inner droplets not exactly going through a single droplet combustion right whereas the outer droplets are going through this because there is access to air so effectively fuel is sprayed and the air entrains so droplet at the core droplets at the core may have insufficient oxidizing ambience now so what you have to look at is the competition between entrainment and evaporation right so if entrainment is fast and or or okay it is a combination vaporization slow so entrainment is faster vaporization is slower than what do we expect air is now beginning to get available to most droplets and therefore most droplets can burn by themselves they are harder to evaporate therefore they are going to be waiting for the flame to come near them okay oxidizer to come near them and the flame to happen near them so this actually leads to single droplet burning more towards single droplet or so or droplet burning singly or in groups right now once you have a single droplet mode of combustion that is established then it is difficult for the flame flame to coagulate and then have a outer envelope flame because once you have the flame you do not have fuel penetrating outside of the flame so the oxidizer has to come to this to the flame in order to consume the fuel right so once you have this mode of burning this persists it is kind of like a stable solution that the system approaches on the other hand if entrainment is slow right and or or vaporization fast so this now leads to a flame that is actually enveloping a what is called as a spray sheet so now you can look at a spray you now have a cover around this and that is exactly why you expect the flame to happen so this is envelope flame at the spray sheet now once you have a envelope flame then that is not going to let the oxidizer get it okay so the droplets will now be waiting for the oxidizer but no oxidizer is it coming because it is all getting consumed in this flame so they just begin to get evaporated because of the heat from this flame and they will have to undergo continued and undergo combustion in the envelope flame so once you have an envelope combustion mode it is it sets in and it persists you it is hard for it to transition into a drop that combustion mode right so this persists now typical examples of these are for example if you now look in at a situation where the vaporization is slow that means we have to look for materials that are less volatile okay so typical example of this would be even solids for example look at coal particles okay so if you now look at pulverized coal so cold or cold dust okay example coal dust flame now the example of this would be the second one where the evaporation is fast is essentially oils so oil flame right where where the where where the oil is typically quite volatile and so the oxidizer spreads the fuel the gaseous fuel spreads out and meets the oxidizer even before it can enter in train significantly so then what we have to look for is how does how does this what we call as a cloud combustion or a dense spray combustion happen we define something called a group combustion number or we can you can call it a group group combustion index or number this would be called g and this is defined as n capital N dl not divided by L where n is the total number of droplets total number of droplets that can be now written as I should say goes as nl cubed where n is the number density that means number of droplets per unit volume and L is characteristic dimensions right so essentially what we are saying is if you now have a total number of droplets times the diameter divided by the characteristic dimensions let us say for example if you are looking at a spray flame or a swell flame where you are sending in the liquid in a swell flow and so on you have like a burner diameter so within this burner diameter or of the order of the burner diameter how many droplets can you space is essentially what is in what is indicative of the group group combustion number and what it basically means is if you have a large g it indicates a group group combustion if you have a small g it indicates single droplet combustion group combustion and small g single droplet combustion now in reality you could have also things that are in between that means you have small clouds of droplets that are burning with a flame enveloping it but many such clouds separately right as opposed to when you say group combustion it is like all droplets that are there or having a single flame so there is a reality that is in between so it is like these are extreme cases right so what would and then the other thing that you have to point out is this is purely a geometric parameter right so we are talking about what is like the spacing between the droplets if you will so g is purely a geometric parameter and it does not take into account these things like we are not looking at how well is the entrainment happening versus how well the vaporization is happening okay so these two will keep this in mind but but before before we proceed with taking into account those in a in a spray jet flame but what we will think about is is it possible for us to think about like a spherical cloud of droplets right what could happen if you now have a spherical cloud of droplets as a function of g so if you now start from a large g towards a small g what happens to a spherical cloud of droplets now there are four possibilities that that can that can happen with with the spherical cloud of so consider a spherical cloud of droplets right so what we are basically saying is can we have a large g situation where we are looking at a group combustion and what that means is you now have lots of droplets that are in the core and they are non-evaporating right so if you now have like a slow vaporization situation then let us suppose that you now have a spherical boundary imaginary boundary spherical imaginary spherical boundary of non-evaporating non-vaporizing droplets and out of which you now have let us say smaller ones which are evaporating droplets so they are obviously much smaller and I am just representing them by a dot and you can now talk about this as the spray boundary so in all the pictures that I am going to draw off the four possibilities the broken line refers to what is called as a spray boundary okay so there is another way of thinking about this it is you can look at like a spray that is coming out of the board right in a cylindrical manner it does not have to be spherical but you can look at things happening in a circular manner as a cross section right so it is like you now have a non-evaporating core and a evaporating surrounding that forms the spray so this is the broken line basically means this jet the spray boundary so this is a vaporizing droplets and the broken line is the spray boundary and you now have the actual flame around this right now as you now increase your sorry decrease your g as you now go in this direction of decreasing g the other possibility is you do not have a core of any non-vaporizing droplets that means this diameter basically shrinks to 0 you are now beginning to think about droplets that can vaporize faster but still not fast enough for flame to eat in okay so you know you now have a single spray boundary without having to distinguish between vaporizing and non-vaporizing droplets because all of them are vaporizing so that is vaporizing droplets and then you have a flame around right now the next possibility is for the flame to move in okay into the spray so as I said the broken line is the spray boundary so the moment the flame moves into the spray boundary you now begin to have single droplets in the periphery single droplet burning in the periphery and then you have group combustion in the middle so that gets us to a situation where let us suppose that you now have this picture of vaporizing droplets in the middle and still it is not the spray boundary you have actually have the main flame now we have to distinguish between main flame and individual droplet flame let us for those that are burning outside this so those are individual droplet burning right and this is what constitutes your your spray boundary and finally the flame now eats into each and every droplet there okay so that means you now have a spray boundary in which all droplets are burning individually and so on right so this is say limit of low G and this is individual burning and this is this is now OG right the question is what happens so this is as if like you had these droplets kind of put together in isolation as if they were not part of a flow right and then we were beginning to play with the G so if it if there is a high G then there is more group interaction when there is low G there is less group interaction you have more individual droplet burning and so on but what happens in reality for something like a spray jet flame the answer is the spray jet flame you now have a flow field with a variable G so you start with something's like a very dense spray that is just beginning to atomize and then spread out and then you now have more and more entrainment that allows for individual droplet burning for the route so it is like a variable G that starts with a high value and then keeps proceeding along the low value so this is where it is not just purely a geometric parameter that we can rely on we have to bring in the flow effects therefore in a in a spray jet flame G is variable so you now get into a situation where let us suppose this is a centerline and let us say you have lip of the nozzle and which issues out the spray and you can now think about like a potential core and you now have near the near the centerline you have bigger droplets but away from the centerline let us say you have smaller droplets because they are evaporating now you have a the main flame or the internal group combustion flame right and outside of which as you now keep going the the G actually decreases and you now have lots of cloud drop cloud combustion going on right forming the spray boundary so this is like the maybe keeping with the convention we should use broken line spray boundary and this is multi-droplet combustion and there is a overall turbulent flame brush that we will have that that encompasses the entire flame and so that is that is essentially a turbulent flame brush we will be we might look at it when we do turbulent flames that is it is an envelope of all the fluctuations right so that is let us say that is a turbulent flame brush how do you formulate this proud this kind of problem right so the way we have to do it is obviously to deal it deal it in a deal with it in a statistical manner so we have to look at how to do spray statistics spray statistics what you do is you now have what is called the spray distribution function function f of f of r rl which is the droplet diameter position x velocity u u vector and time such that this is like a density distribution that means f of rl u x to say x plus u and t d rl dx vector du vector so this is basically a seven dimensional space in 3d right so you have three components of velocity and three directions of location and then the radius so this quantity now right indicates the number of droplets of radius between let us say in range rl to rl plus d rl velocity position in range x to x plus dx that is within this bin and velocity in range u to u plus du right at any time t it is time dependent all right so we have to now let it let this fluctuate in time so when we now use the word rl sorry the the quantity rl we are implicitly assuming a spherical symmetry so zoomed there are ways in which we can relax this but we have to see when this is this is relaxable so the now typically small droplets for example if you are looking at things like 10 microns and so on 10 to 100 microns like they look at that range for most typical fields you have a significant surface tension effect that spherodizes the droplet okay so the sphericity is maintained because of the surface tension therefore we have to actually look at what else is causing the droplet to be non-spherical as competing against the surface tension so what typically allows for the droplet be non-spherical is when it now tries to flow you now have a shear that is happening at the surface as well as a hydrodynamic instability because you now have high density and low density interface which becomes unstable and so on these things are obviously proportional to the relative velocity between the two the droplet and the surroundings okay so the droplet were to be stationary you do not have these effects right so therefore the Weber number Weber number describes the effect of surface tension relative to that of the dynamic force on the droplet so we that is a simple symbol for Weber number is to RL that is for the diameter gaseous density times modulus of u vector – v vector the whole square that is a relative velocity between between the droplet and the ambient gas divided by sigma which is the surface tension so u is the droplet velocity v is the gas velocity right now for we greater than or greater than or equal to about 20 droplets tend to deform and break up so if you are looking at atomization situation you are looking forward to deformation of liquid sheets into ligaments and ligaments to droplets so you are looking at a high Weber number situation okay but once you get to fairly small droplets the Weber number becomes small and then the surface tension takes over so for a Weber number greater than 20 droplets tend to deform and break up so given this we can now write what is called as a spray equation for f on how this is actually going to go spray equation is a dynamic equation for f RL dot f plus now a divergence with respect to x of the droplet velocity carrying the f and a dynamic for a divergence with respect to u of the body force all equal to a s where now we will now explain these terms RL dot is something that we are familiar with which is DRL over DT right so this basically tells how this f is going to change because you are having a evaporation or burning that changes the R at a certain rate with respect to time and for example if the D squared law holds right we know that RL dot is goes is 1 over RL right that is something that we have seen before G is as I said as a force per unit mass whatever forces are acting that that change the droplet the spray the distribution function and s is actually the most important thing and also the most difficult thing is essentially the source term and essentially you are to look at two sets of quantities one is creation and destruction so creation and destruction so it is essentially a net source term of droplets right so creation is like for example by atomization and destruction is by coalescence and let us say impingement with the wall right so wall collision etc so it is kind of like what is called as a population equation that that keeps track of the droplet population given by f and what you are looking for is how do the droplets get created and destroyed as a source of this that is getting dynamically going in a flow field now these are difficult to model and the fidelity of this equation lies in actually how we model this and that is where all complexities remain


Three Navy sailors and three Navy spouses reached a huge milestone at Rhoda's naturalization ceremony. This infrequent but highly significant ceremony marks the day individuals are granted American citizenship. I didn't expect to be an American citizen. I was a kid, but now look at me now. Not only are these new Americans elated to have completed this process, but some are already looking towards the future. It's a great feeling.  So therefore I'm really happy that this is behind me now. Schmitz also wants members of the Rhoda community to know that if they'd like to become a naturalized citizen, to look no further than our local legal office. For anybody who is applying for U.S. citizenship and is in Rhoda right now, just write on your application that you want to do the interview here. It's great that AFN spreads the word a little bit for all the other people out here. Lance Corporal on a Kamuti Naval Station, Rhoda.


Live from Las Vegas. It's theCUBE, covering ServiceNow Knowledge 2018. Brought to you by ServiceNow. Welcome back to theCUBE's live coverage of ServiceNow Knowledge 18 here in Las Vegas. I'm your host, Rebecca Knight, along with Dave Vellante. The beer and the wine are out, so it's getting time to party, but we have another guest here on the show, Stephen Lee. He is the Senior Director of Business Development and Partner Solutions at Okta. Thanks so much for joining us, Stephen. Thank you. Great to be here. So why don't you just lay the scene for us? Tell our viewers what Okta is and what you do. So we're an identity and access management company, cloud-based. When you think about every organization, right, with all the different kinds of users, employees, partners and contractors, there's a lot of need for them to have access to things that they need to, where there's an application and from different devices from anywhere. And our mission really is to connect anyone to anything.  And it's not just about employees. I think a lot of people think of security products. They think about, well, you know, employees having access to different systems. It's beyond that. When you look at the persona of users now, is employees, as partners, as contractors, is our customers, our customers' customers, which most likely would be consumers. So it's a huge space and we're definitely filling a big gap in the security space. So I got to ask you. So I like the tagline, connect anyone to anything, but I want you to add a word, safely. Connect anyone to anything safely. I would add a couple more words. I think it's securely. I think it's more effectively, because it's not just a product for end users. It's also a product for IT folks. It's been a very difficult problem for people to solve, and we want to make, we want to have a solution that's easy for IT to deploy and not have to worry about maintenance, having it running in the cloud. I think it's a very same message as what service now has, which is providing the best platform so that IT can provide a good solution for the end users. I mean, we're not building a solution for people walking around here. We're helping the people here building a solution for their audience. And these are the end users. These are the consumers. So it is about easy to use. It is about security, but it has to be user friendly. It has to be very effective. It has to be cost effective. So it's, you could put a lot of adverbs behind that line, I think. You got a nice booth here in the big meter board. Okta plus service now, better together. What makes them better together? Talk about the partnerships. Why better together? Think about service now as a platform, right? Yes, it does a lot of complicated workflow, IT, SM related stuff. And I think at the end of the day, we're solving problems for end users. How are they coming in? How is somebody coming in to file a ticket? How is somebody coming in to request for a service? And I think Okta does the same thing. It's about providing access in a secure way for end users. So one of the original integrations that we've done for service now was, was all about making sure that end users can get to service now easily and securely. That continues to be a main theme of our partnership. But increasingly when you look at service now, the platform expanding to other security disciplines, right? The SecOps module that was released last year. We've done a lot of work with that. In fact, early this year, we released what is called an Okta Cloud Connect for SecOps. And what that does is really when you think about Okta as an identity product, the information that we learn from users and how they access various things. It's actually very useful information and can be used as triggers, can be used as data points. And when you look at a security analyst looking, looking at from the lenses of SecOps, they get to see that data, right? You see an incident. What do I know about Steven? It's just a ticket. Someone logged in or someone is having trouble. The integration that we've done allows you to get additional insight about the user from within the service now module. So you understand who the user is, who he or she reports to, what have they been doing recently? And it gives you much better context when it comes to solving a problem or trying to resolve an incident. So that's just yet another integration that works very well together. Definitely looking forward to all the new things that that service now is doing. And I think at the end, it's because there's such an important focus around end user that makes the two products work really well together. I mean, it's a big space, but a crowded space. I mean, you guys are doing very well. Why, how were you able to differentiate from the pack?  I think it's customer first. I mean, that is the number one thing. When we look at it, it's not about throwing protocols at people, what features we have and all that. I think when we work with our customers, we figure out what their problems are. What is the use case? How can we help you solve your problem? And I think in a big way, it's a very similar message with service now. It's not about the platform. It's about what you need. What are you trying to do for your end users? And I really think that that's a big part of the success. On top of the fact that the product is built on a very sound platform. We're the first cloud-based identity and access management product. We started the category and we're still at the top of the category. So, great product, but I think the focus around customer success is really what has kept us going. You said before the cameras were rolling that the tagline for service now, making work work better for people really resonates with you. It does, because I think you mentioned our tagline earlier, right? Can I get anyone to anything? And I think at the end, we want to make the workplace a better place. Like I said, we're not about the folks here. We're about helping the folks at this conference build a better work environment so people can have an easier time and be more efficient, be more productive. But more importantly, be able to work in an environment that is also more secure, obviously from an identity standpoint. But it extends beyond work. I think you're also looking at us reaching out to consumers, to our customers' customers, but achieving the same purpose, making their life easier. And that's why I love listening to the keynote today and I feel like it's a really good message and I totally agree with that message. Well Stephen, thanks so much for coming on theCUBE. It's been a pleasure talking to you. Well, thank you very much. Thank you. We will have more from ServiceNow Knowledge 18 and theCUBE's live coverage in just a little bit.


So the theory for a perfect lens actually originated in about the 1960s, a guy called Victor Vecilago. He said that you could get something called a negative refractive index, which essentially means that when you look at a prism or something like that, light tends to bend a certain way. And he proposed that you could get light to bend the other way if you so wanted. And this is the basis point of perfect lens. Current limitations with optical microscopy are mainly due to something called the diffraction limit, which was divided by a guy called Ernst Ab in 1873. Now the problem with that is that light is a wave, and as a wave, it diffracts in certain ways. The fraction of it means that it can only resolve down to a very small spot, but a fixed size of spot. So you can get to about 200 nanometers across, and that's about, I'm talking, a millionths of a millimeter. And you can't go any further than that due to the wave-like nature of light. So that's a big problem. The refractive index of material is how much light slows down when it travels through such a material. So the light is travelling from air and into water. And when it hits the surface, it reflects a little bit, but it also transmits, and it bends at an angle that's related to the difference in refractive index between the two materials. Now water, and pretty much all materials in nature, have what's called a positive refractive index. So what's happening here is the light is going from air into water, and you can see that the light is bending towards the normal when it enters the more dense material, which is the T. If this wasn't T, but a negative refractive index material, something different would happen. The light wouldn't be on the left-hand side of the normal, it would instead be on the right, so light would come in this way, but then bend back on the opposite side to the surface normal. The actual idea for a perfect lens for it to be used to image things came up with a guy called Sir John Pendry in about late 1990s, and it was demonstrated in early 2000s. And this idea basically uses a metamaterial. So a material that's comprised of very small structures, much smaller than a wavelength of light. And by arranging those structures in certain ways, you can amplify light waves and get them to diffract the wrong way. And you can see images you wouldn't normally be able to see on a much smaller scale. With nanotechnology, you're dealing with things that you can't see. So it's really important that you have these tools that allow you to see a nanoparticle inside a cell that's really complex. So if you're doing bulk measurements just on a lab bench, it's difficult to interpret the results. And that's where microscopy and high-resolution optical microscopy and electron microscopy are so important. And more so now that we're dealing more with nanotechnology. So we look at the interface between nanotechnology and the immune cells using nanomaterials to try and control the responses where the body decides, the immune system decides whether it's going to attack an infection or a cancer or whether it's not going to. And the reason that's a nanotechnology or a nanoscale problem is because what these high-resolution microscopies are beginning to reveal is that there are a lot of exceedingly small structures, so down to the level of tens of nanometers or less. And these structures are critical to the way cells talk to each other. So when your immune system decides whether it's going to attack something, there are spatial structures at that size which are helping to mediate that decision. So the ability to image those is vital to understanding that. And it's also vital to understanding how to control that process if you want to for therapeutic reasons. In our group, we're interested in looking at the interaction between a cell and nanoparticles. And you can't currently see that in the conventional optical microscope. But if you could watch where an individual nanoparticle is interacting with the cell, what compartments it's going into, what effect it has on the cell structure, that would be really interesting to do in a live cell. And cells, when they're alive, they're generally quite transparent and colourless. So you'll have to stain them if you want to see them. And that is actually obviously influencing the cell itself. And you don't want to do that because then it starts messing with the processes. Not only are the imaging techniques coming online, but also nanotechnology techniques that enable us to build structures on the same size as these vital structures. I mean that we can interact directly with these vital features. We can help try to control their size or to pull them around or to position them. And so these two technologies coming in parallel should really show some exciting results. Perfect lensing principles have actually been demonstrated already on things like maybe 20, 30 nanometers, which is already a good 10 times below the diffraction limit. So we've shown that it works. It's just going to take a bit more time or maybe a little bit of someone's clever idea to make it actually a reality.


Now, 70 religious groups, trade unions, organizations, and individuals have presented or represent with different brands of vehicles. Courts of the Governorship Candidate of the All Progressive Congress, APC in Adamawa State, Senator Aisha Dahiro Ahmed Binani, making the presentation at the Muhammad-Buhari Square, Jimet Ayola. Senator Binani said the gesture is in fulfillment of our campaign promises and charged beneficiaries to make judicious use of the vehicles. And back on many developmental projects across my material zone, we are making good laws that have direct direct and the lives of our people to the construction of classrooms and massive supplies of instructional materials to arrest the family of standard of our education, education system. In hospitals, we have vision of portable drinking water, yearly distribution of free fertilizer to our prison farmers, unprecedented empowerment of our people to be self-reliant among others. Today is yet another historic day in collaboration with the National Directorate of Employment. We are about to present our religious organizations, women, youth groups, different groups, individuals with SANA, 2008 model, 2005, 2001 model, four heroes, and totaling about 70. In addition, despite representing Adamawa very well, a very different national mix. I am not unaware of the difficulties faced by our football teams whenever they want to travel outside the state for matches. P.J. P.J.


told in future the National Broadcasting Company in cooperation with Street and Smith Publishers of astounding science fiction bring you dimension X My name is John L. Hayes and private investigator Maybe you heard about me. I cracked the Turner kidnapping back in 1946 It wasn't very hard. I paid off a few stool pigeons and went right to the hideout I did my reputation a lot of good though Enough good for me to be called into the mayor's office down at City Hall to see big Mike Flaherty himself Sit down. Sit down. Thanks You have to forgive me for speaking so low. That's a bad case of laryngitis.   Mayor? You didn't call me in to discuss the philosophy of growing old gracefully Listen, I want you to do some investigating for me Naturally, it must be confidential. This is a confidential business. All right Here's the day man came into this office and sold me a vial of radioactive water that he called the relixer of life I'm supposed to cure you of any disease and keep you healthy enough so you live a hundred years That's none of my business mr. Mayor, but how much did you drop on this gold-breaking? It's About fifty thousand dollars Hmm You uh, you don't seem the type somehow and come a little closer to season And we did tell you something my political opponents would give their right arms to know this Isn't laryngitis It isn't it's inaccessible for surgery It's really be dangerous How much time I have left? I don't know but I look like a man who's going to that chair Isn't if I want a vacation I pack up and go if I want to drink I take one If somebody comes to me with a vial of liquid and says it'll keep me alive I think twice before I throw him out as a crackpot What do you want me to do get your money back? The money isn't important. You mean that the loyal opposition got hold of the story. They could use it against you That's part of it, Asian However, you don't have the whole picture yet Shortly after I bought the stuff I received an anonymous phone call I was warned not to take it I was told it was poisoned and would kill me in a matter of seconds. Ah, the plot thickets. Are you going to appreciate my position? I feel like a man who can either save his life Or destroy himself by taking that stuff Well, the phone call might be a hoax. Yes And so might the elixir of life Yeah, very likely What do you want me to do about it? Investigate the man who sold it to me Find out who's behind him. What he knows where he goes Nothing else. I want that 50 grand back What's in it for me? A grand If he's on the level 10% if you get the dough back Deal deal He's a vial and he's his card uh-huh Arthur C. Layman longevity experts 45 Billings chords Okay, mr. Mayer, you got yourself a boy. Good. I'll leave your working name and phone number with my secretary I'll have a sender check. Right. I'll call you You were in there a long time. How'd you make out? Swell. I bought the outer drive for only 10 bucks on the cost of mailing. That's kind of high last week We were selling it for only five. I'm sorry. I've been listening to too many detective programs It isn't polite to stare I was just wondering what your name was Sign on the desk says katharina cooper.  He said she was feeding me to the vultures piece by piece I left my card and walked out By the time I got home it was dusk It was the time of early evening when every bachelor wishes he wasn't one especially after meeting a girl like kathy The phone began to ring just as I put my key in the latch I made it on the fourth ring Hello I live alone and don't like it. Were you expecting someone else to answer it? This is a warning mr. Hason Don't touch your bed I'm sorry, but I don't like to sleep on the floor The joys of being a private detective. Oh, hello, jaco How's my boy? Add to that good boy Oh, jaco, be glad you're not a private detective with all kinds of crack parts calling you up and trying to get you to go Sometimes I wish I had shaggy ears like you so I couldn't hear them Come on boy. Come on in the bedroom for a change or something Oh boy, you want to go out? Well, you just wait until I sit down here and get these shoes. Hey, hey there. Don't jump on that bed bed. Now, you know better I'm gonna fly When I looked more closely I saw that the bedspread had silvery threads of fine spring steel woven into it It had been set like a bear trap to spring shot and strangle anything that touched it Somebody wanted to get rid of me pretty badly somebody to whom I had suddenly become very dangerous Instead they got jaco My poor little jaco I decided to take a fast drive over to billings court to see arthur layman monchevity expert I'm looking for mr. Layman's office. I'm the janitor. You didn't need to explain Yes, indeed mr. Layman, isn't it? I just said I was looking for his office. Oh, it's a detective Now I'm really a vacuum cleaner salesman I just had these credentials printed up for fun here by your wife and muskrat coat I can't take any money I'll just keep this to the tip. What floor is it on? Up those steps. Thanks Looking for someone Mr. Layman A janitor told me you weren't in so I will pick the lock. Yes. I hope you don't mind not at all If you put down the gun, I like to hold it. It gives me a feeling of power Now mr. Hayes, mr. Hayes, and if you will tell me just who you are and what you're doing here I couldn't sleep My bed had a dead dog in it. I thought I should consult a health expert. Who sent you nobody sent me. I'm like topsy I just groaned. I'd like to keep on growing mr. Layman.   Hayes, and I don't have the faintest interest in trying to kill you On the contrary it was I who telephoned and warned you about that bed You know about that phone call. I ought to I made it What's the pitch mr. Layman? I can't tell you what the pitch is mr. Hayes But I will tell you this Give that bile of liquid back to clarity and let him cure himself or poison himself Look mr. Layman. I wasn't born yesterday Don't give me this elixir of life stuff.  Hayes and give back that 50 grand and I'll become very unstubborn I Have a suggestion. I'll bet you do why don't you safe enough the tiniest drop of that elixir and have it tested on say A rabbit then if it's non poisonous you can go back to clarity and have him drink and while we're proving It's caramel water.  So don't try anything Shall we go before we do just one thing? Well If you didn't try to kill me Who did Who else knew about it?  How long would it take 24 hours at least okay? How much 50 dollars my friend will pay Your face yeah, the gentleman Holy jumping sunfish, sir Look, you saw me come in with a guy just a minute ago didn't you yes, sir But he left when you started talking to me isn't that just dandy is something wrong? No, nothing much. You know what barnum said about one being born every minute. Yes, sir Well, he was talking about me. I better get going. Yes, sir. Oh, sir. What about that kiss? Okay, I suppose you might as well do it just for laughs Send the report on the bill that donald hasten private investigator cater building. Yes, sir Pointing going back after layman. He was probably well on his way by this time It was an all-around for me story from beginning to end But still somewhere hanging around the edges of my brain was a funny kind of hunch If layman had wanted to kill me then who called me up to warn me layman himself Why it didn't figure I stopped to look up an address in the phone book and then I invested 10 cents Why don't you do it over a cup of coffee? I have to talk to you Very late a sleep late tomorrow, please There's a coffee shop near your place. I'll be there in 15 minutes soft blonde hair She seemed genuinely happy to see me it threw me for a few seconds And then I reminded myself I had already won the pt barnum award once that night My name Arthur C layman Am I supposed to refresh your memory? I had a talk with his honor about him. I I don't remember Look, I used to have a little scotch terrier named jockel. We liked each other.  What goes on? I don't know anything about it. Listen kathy Maybe I'm getting sentimental in my old age But for a moment there when you walked in I thought you seemed genuinely glad to see me Wasn't because you were glad I was still alive. Come on give Don, I liked you. You're a nice guy Why don't you let it alone call flowery and turn down the assignment Give him back as well and tell him you're not interested in finding layman Would you do it? If you want to help me so much why not tell me what it's all about. I can't I'd like to but I can't I've told you too much already Somebody's got you real scared honey. Who is it? You're too nice a girl to be mixed up in this garbage with a guy like layman Come on. Tell me I can't just believe that please Get out of it now before it's too late Okay, honey, you can play it that way if you want but to me it's as thin as a bowl of restaurant soup Poor jockel knew something and couldn't tell me you know something and you won't tell me Good night. I am ca and I didn't sleep very well It went around and around in my brain like a squirrel in a cage, but it didn't add up to anything when it came out In the morning I went straight to my office and locked myself in with a bottle of gin By 10 o'clock. I had decided to quit the job, but before I could call flowery and tell him The phone rang Go ahead Mr. Hayson, you got it. This is dr. Gregory the base at biological laboratory. If you want the money He isn't about the money. What's up? Mr. Hayson Do you have the formula for that serum you gave me? No, I know a guy who might but he's in out of mongolia by now. Why? But I've never seen anything quite like it. I don't know if it's just a freak of fate or what happens? Well, let's take that disease my undershirt as I put down the receiver Where do we go from here? Was layman on the level after all? The next stop was layman's office. Maybe he wasn't in out of mongolia It was noon before I got there the same janitor was on duty in the same dirty lobby Hello there. Hi Want something layman who layman Now wait a minute junior, you'll remember me last night five bucks real office first floor I don't know what you're talking about. Mr. Are you one of the five a junior? Well this time?  I'll try to stop me if you want to work tomorrow But there's nobody in that office.  Sit down jr. Sit down over here on the window ledge Okay Listen, I don't know anything. Maybe you saw something like this in the movies junior There's this guy see a killer and he sticks another guy with a needle that has a slow poison on the end of it Like I have right in this little glass file see it And only this killer has the antidote if the other guy doesn't talk it's curtains in one minute If he does the killer will give him the antidote Okay, junior talk. I I don't believe you There's no poison in that pin. It's a joke. It's up to you junior Don't you feel something different though feel your heart speed up a little from the poison? Now listen, I don't know anything it makes you sweat too When it reaches the brain that's when it really begins to work You've got 30 seconds to spill otherwise 25 seconds Okay, he was here He gave me a hundred dollars to forget it the rent at the office only a couple of days ago And then last night he said he was moving out said I shouldn't mention to anybody that had been here And our lady was gone piles for it turned off. Don't know how I moved all that stuff out so fast Now that's all I know unless that's all I know now for god's sake, mr. Give me that stuff Don't let me just cook Junior there was no poison. You're all right Yeah trick. Thanks for the information a trick a trick He said he'd shown me thanks again and right back on the horns of ye olde lemma The only thing I knew for sure at this point was that the serum was apparently not poisonous And since my client was most concerned with that I made my next stop the office of his honor mayor big mike flowery I had the vial in my coat pocket Hello beautiful I want to see his honor He isn't in I'll go into his office and wait you can't but I can come on in. I won't talk to you anyway.   I see you didn't listen to my warning No, I didn't what's more I found out that this layman character is on the level about the serum it works Found that out too. That's right. It leads me to an interesting conclusion kathy Namely that you're the one who tried to booby trap me All right, have it your way What do you intend to do? Well first I'm going to give flowery that serum and let him cure himself. You mustn't do that. Why not? I I can't tell you but you mustn't Down in a few minutes mike flowery will be here before he comes I'll have to ask you to give me that serum try again I don't hear so good. Maybe you'll hear this It works too. So don't try anything Well, well, so now it comes out Okay, kathy if you want to play that way go ahead.  Give it to me Pull the trigger baby You're weakening done.  Please What is it baby? True love or just weak in the knee You better handle that gun Tom what can I do? I'm so mixed. Well, that's better Well, what is it kathy? You're no killer. Tell me what's going on here. Maybe I can help you. You gotta trust me No, no, I can't don't believe me I want to but it's against the prime injunction The what? You wouldn't understand. There's no way I could make you understand only believe me don't because I love you You mustn't let layman succeed in giving that serum to mike flowery The consequences would be unimaginable You know kathy If you had come to me and leveled right at the start, maybe we could have worked something out Maybe I'd be listening to you now But you're a little late because I just heard big mike coming to the outer office. He'll be here in a second Don't don't please come in How do you do? Layman, I see she's been trying to get the vial from you mr. I was afraid of that I came over to make certain that mr. Flaherty is permitted to drink the serum. That's very noble of you layman, but I don't quite understand it You have your 50 grand. What do you care whether mike flowery lives or dies mr. Hason if mike flowery dies the opposition candidate will win the next election That means a new political party will come into dominance in this city The next president will be a representative of that party I am most anxious to see that that does not happen The entire future of our country indeed the history of the world would be affected by it He's telling the truth don't but events must be allowed to take their normal course.   I'm getting pretty fed up with being told. I don't understand understand what? I understand that in the past 24 hours somebody's tried to kill me I understand that layman's serum will cure a guinea pig and probably a human I understand that unless i'm completely insane the entire contents of layman's office vanished in a few minutes I understand that you two seem to be more concerned with some nonsense. It's going to take place in the future and Oh, no, no, it's too fantastic. Just too fantastic to even think about Something troubling you mr. Hason, perhaps I can help you Perhaps you can layman i'm going to ask you just one question very well When Are you from that does it doesn't it mr. Layman? I've guessed your game I'm afraid you have mr. Hason I am as you surmise a traveler from the future And since you stumbled upon it Perhaps miss cooper here would like to fill in her part of the story What before she does up your hands both of you higher Don't move I'll take that god mr. Hason Now miss cooper you may enlighten our backward friend Go ahead catty Both layman and myself are from the future don't why didn't you tell me? I couldn't the prime injunction to time travelers is never to reveal their identity The penalty is death Since you've guessed it as we feared you might there's no point in trying to conceal anything further go on Mr. Layman's a fugitive from the era in which we live Using one of our time machines. He came back to your time And he sought to change things so that he'd be in a position of great power in the future How do you figure to do that if laity lives long enough he could dominate the political picture in america You're almost right except in one detail miss cooper Fairly will not survive he will live only long enough to gain a position of political dominance Then I will remove him and my own ancestor will take over the reins of power leaving them eventually to me I get it now But there's one thing that bothers me Who was trying to kill me? I was You see I was sent here to track down layman I set that spring before I met you as soon as laity hired you to help him I did it on orders from the council. They're afraid you'd be successful in saving laity's life then unfortunately I I fell in love with you and couldn't go through with it I called and warned you you took credit for that layman. I wanted to remiss you on my side mr. However, it makes a little difference at this point since you know the entire story I have little choice now Do you think you can get away with this? I believe I can mr. Hissen there are two of us here. We'll know your plans other time as de flair to return to his office There will be only one myself Goodbye mr. Hissen It has been Saw Kathy jump toward the desk and push a button.  I I'm sitting in flirty's office That was blood on my shirt and it's gone now here. You drink this I don't understand it. Have I been dreaming? Is the whole thing nothing but a nightmare Well, it seems so real that there was a man named layman He ployed a gun at my head and shot me I I felt it. I tell you I felt it gone gone. Listen to me Listen carefully. There isn't much time and please darling. Please this time. Believe me. Listen Go ahead. You were in this room layman did shoot you.  You're insane. No What he didn't know was that this office is a time machine We rigged it that way hoping to trap him here and take him back to future time When I saw you was about to shoot you I jumped through the switch that sets the machine in the reverse We went back into the past before he killed you That's where you are now It's only a few minutes before layman is going to knock on that door and come into the office But it's too fantastic to believe cat What can I do? Thanks a lot. Make it now before layman gets here And then when he comes get the jump on him since you're the one who went back in time You'll remember but layman won't What'll happen to us? They'll appeal to the council. Perhaps they'll let us stay together I can't make my brain believe this cat You must Don Don for our own sake for the future's sake Breaks a vial now in a moment. It'll be too late. Well, I don't know catty Clarity is life depends on this little glass bottle. I'm sneezing It's layman time. You've got to decide now. No quick come in mr. Layman We're ready for you You just heard another adventure into the unknown world of the future the world of Dimension X is presented each week by the national broadcasting company in cooperation with street and smith Publishers of the magazine astounding science fiction Today dimension x has presented Untitled story from the current issue of astounding science fiction It was written for radio by george lefferts from the story by frank m robinson Featured in the cast were george peteras hasten and sergeant as catty bernard lenro as layman Your host was norman roll music by albert burman Dimension x is produced by william welch and directed by fred way Dragnet the story of your police force is next on mbc


Welcome back fellow techies to our latest tutorial video, I am The Technician Project. Today's tutorial is going to show you how to combine all your acoustic mix together in Logic Pro X, part 4, putting everything together. So where we left off from part 3 is we did our vocal mix and from our previous videos we've done our guitar mix and panned everything as well. So now we are ready to combine both the tracks together so the guitars and the vocals to make one big mix. So we're going to click unhide our mix and we're going to unhide all the tracks we want and unmute all the tracks we want. This is the perfect time to load the mixer and keep an eye on the master faders and the subgroups just to see what the outputs are going to be like and we're just going to play the track all the way through. Now that was the first time we listened to the mix all the way through with the vocals and the guitars and I personally think it sounds okay at the moment. There's no major issues. I would potentially adjust the vocals throughout the piece and maybe bring the guitar down slightly. So we're just going to do those little tweaks now and just have a little play with the system so let's jump in from the beginning and we'll mix as we go along. Now during that little playback of the track there all I done was adjust the vocals slightly. I brought in the second main vocal line, the main vocal effect just to see what the difference would sound like with an extra vocal line. I moved all the effects over and copied them over. I brought the level down and maybe done a bit of panning but I wasn't too short. I didn't really make too much of a difference and I wanted the main vocals to come straight down the stereo field so with all the other panning going on it's nice to have something down the middle. I've turned up the stereo mix a little bit and I adjusted the reverb on the guitar just to make it a bit more reverberant. It gave it a bit more colour in the mix and I also adjusted the reverb on the main vocal to turn it up a little bit and the harmonies 1, 2 and 3 so 2, 3 and 4 just to improve those harmonies coming in. I think it sounds pretty good now so I'm happy with the mix. What we did is we did our mix in different sections as you saw in previous videos so we did our guitar mix with the reverb and then we did our main vocal mix which is quite a lot of vocal tracks if you think about it but that's because it's quite a lot of harmonies involved and a lot of different effects so because we did all that separately it's actually come together quite well and usually these mixes don't happen like that usually you mix certain bits and then you play it all back and something's slightly off but in this mix it seems to work really well. See our next video, it's ready to bounce out. Thanks for watching, don't forget to like the video if you enjoyed it and subscribe for more and also ding dong that notification bell to get further updates. Thanks again, goodbye.


Good afternoon, everyone. Thank you for attending this presentation. Today, I'd like to introduce reproducible and maintainable embedded Linux named DB. I've already made several presentation in the Linux conference in Japan. So in this presentation, I'd like to explain some abstract of the DB and also new features about it. This project is called Shared Embedded Linux Distribution, which is one of the activities of the C working group project. The goal of the project is to create an industry supported distribution and provide the long-term maintenance. Please visit this webpage for more details about the project. Then today's Linux is running on a lot of many embedded systems including the civil infrastructure. Then when we choose the distribution for such system, we need to consider the number of supported packages and their versions, supported hardware and the stability and so on. In our case, we want to make custom embedded Linux environments, and we need wider hardware support and stability and long-term support and customizable build systems. Especially long-term support is the most important things because the most products in the civil infrastructure required over 10 years support. Our solution is to combine the Yacht Project Pocky build system and Debian source code with MetaDebian. MetaDebian generates a reference distribution named Debian. This is the definition of the terms, and MetaDebian is a layer for a Pocky build system. This is separated from the core components of the Yacht Project named Open Embedded Core and other layers. Also, it allows the cross-building Linux images using the Debian source code, and the source code is available on the GitHub. Debian is a reference distribution that is built with Pocky and MetaDebian. The name of Debian comes from Debian and Pocky, and it also comes from the Debian line. Debian is built from the Debian source, but in the binary package level, Debian is different. So we should call it the Debian-like. This is the default structures of the Pocky build system. The Pocky fetches upstream source code and build the Linux images for the target hardware. Then when we use MetaDebian, enable the MetaDebian with Pocky. Pocky fetches the Debian source code instead. Then build the Linux image called Debian for the target hardware by the same way. This is the target version of Debian. The target version of the Debian source code is version 8.0, this is currently supported. Your project version is 2.0 stable and 2.2 development version. The purpose of Debian is to satisfy our needs, especially to provide the stability and the long-term support with Debian stable release and long-term support. Also, we should contribute to the upstream projects including the Debian LTS. When we create recipes for Debian, basically we follow the Debian's packaging rules. In other words, use the same commands and options in configure and compile process, and the same install process, and binary package name and dependencies as Debian. But as you know, Debian rules the core component of the Debian packages assumes the native build. But Debian is cross-compiled from Debian source code. So we cannot execute the Debian rules directly. Instead, we need to implement configure and compile commands ourselves and also sometimes we need to add some patches for supporting cross-compile. Then also, Debian is intended to not only embedded system but also the desktop PC and the servers. So sometimes we customize some settings for embedded system if necessary. For example, remove unneeded features, unneeded dependencies, and packages. For example, some packages generate UDEP packages that is only for the Debian installers. In such case, we don't need to generate. We need to take care about such packages. About the details of this policy is written in my old slides. So if you want, please refer to this information. From this slide, I'd like to explain how to build Debian and run it on the QM environment, and also explain how to generate SDK and cross-compile your applications and run it on QM. First, simply download Pocky and also download the meta-Debian into the Pocky directory. Please note that the red circle mean the meta-Debian specific space. Second, we need to modify a bit. Change the default configuration by setting the template conf variable to the net meta-Debian slash conf. This mean the core configuration files located on this directory. Then run the startup script that is provided by the Pocky. After these settings, we can run BIPAKE. In this case, generate the root file system and kernel. The built binaries images located on this directory in the case of the QM x86. The final is run kernel and root file system on the QM environment with runQM command. That is also provided to Pocky. Currently, in total, the five QM architectures are supported. The next, build SDK by this command, Bitbake meta-tool chain. Output is generated in this directory. This file, this script is just a self-extracting string. So you can easily install the SDK into your host system just by running this script. Then this is the simplest application and make file. For such simple application, we just need to export SDK environment variables by this command and then make. Then you can get cross-compiled hardware. But the required settings to compile the application is dependent on the implementation of the application. So please refer to the React project manual for more details to how to cross-compile the application. The final is copies the built binary to the root file system image and then run on the QM environment. Very simple steps. Here are the new features of the DB. About the Yoc project, supported version is upgraded to the 2.2 development version. But kernel, the supported version is also upgraded to the 4.4 LTS and 4.1 LTSI. The latest version of the LTS and LTSI. Also, the several new recipes and some target machines are newly supported. Some new useful features are supported. The first one is package management with DPKG and ABT. The second one is a tag-based source code fetch and build. This function is a function to rebuild the Linux image that are built at the specific time, the old release. And the last one is the summary generation. This is a function to generate some information of the packages that are included in the generated root file system and SDK. So from this slide, I'd like to talk about these features in the latest slide. First, I'd like to talk about the package management. This feature is, by default, available in the open embedded core from the beginning. And we also made it available in the meta-debian layer. But, by default, this feature is disabled, so we need to add this definition into our local.conf to use the package management. When we enable the features, first, we can simply add the binary packages into runtime environment. For example, sometimes, temporarily, we want to install and uninstall some packages for system evaluation. And sometimes, we want to install the debug packages for some debugging purposes. And second, we can upgrade packages without stopping the system. And also, we can install upgrades that packages without installing the root file system again. Building and upgrading the root file system in the embedded system sometimes takes time. So this kind of feature is useful for updating each package and quickly. This is the build flow of the bokeh. Each recipe fits the source code and build and generates some binary packages, such as the dev package. And root file system recipes generate the root file system with by installing the dev packages with up to get installed. But by default, there is no data for controlling such binary packages in the root file system. If we enable the package management feature, root file system keeps the data for controlling the binary packages. And we can dynamically install, upgrade the binary packages from the package pool on the build environment. In this case, the app repositories, the package pool, need to be published by the web server. With this flow, even if we update some recipes or source code in MetaLevion, we can install or upgrade the binary packages without installing the root file system again. Next, I explain about tag-based source code fetch and build function. By default, MetaLevion doesn't have the reproducibility. In other words, it cannot reproduce root file system and SDK that was built at a specific time. Because the recipes in MetaLevion always fetches the latest source code, that intended to automatically import the security updates. And reproducible build is one of the essential features in long-term maintenance. We might find some issues three or four years later after we released our products. In such case, it's useful for finding the source of the issues in the old release. And how do we provide these features? First, register a release tag in Git repository every release and add a new global variables Git rebuild tag into the Pocky build system and reproduce an old image by specifying a town name using this variable. I explain with this simple figure. Each line is the timeline of the source code and the MetaLevion. And the circle means the version numbers of each software. If we released a Linux image at this red line, we just register a common release tag. In this case, the name of the tag is R1 to the released software version. And the second release and the third release also register a release tag by the same way. Then, how to reproduce an old release image? As a first step, check out the MetaLevion revision R1. And the recipes in MetaLevion fetch the latest source code by default. So to avoid this, we set the Git release tag to R1. As a result, the MetaLevion fetches R1 tagged source code only. And from this slide, I'd like to explain how to register tag and rebuild in the real environment. First, create a Git repository mirror with Docker. Unfortunately, the default Git repository on our GitHub don't permit to push the tag. So we need to create the mirrors first. We also provide a simple tool to generate mirrors in Docker image. The name of the tool is MetaLevion Docker. So you can easily set up the repositories in the mirror with these two. Then set up the Pocky and MetaLevion. By default, the MetaLevion fetches all source codes from the GitHub by default. So before we pick, we need to change, override some variables about the Git repository servers and the protocols in local.conf. After these settings, we can bit base something using the Git repositories on the Docker image. After built, the list of used Git repositories is generated in the build directory with generated image. Then we can register a tag to the repository with the script GitTaggle.sh. This script read the generated list and automatically register a tag to the repository in the list. Now, ready to rebuild? Or we can easily rebuild the old image by setting the Git rebuild tag variable to the old release tag name in local.conf. And next, I'd like to explain about generation of the summary information. In most product developments, summary information of the open source software is required. For example, the list of installed software and versions addressed where the source code fetched and licenses. Generating such information, summary information should be automated by build system. But Pocky and MetaLivian generate only a list in source software by default. So we added some functions to automatically generate such summary information into root file system and SDK recipes. In Pocky's build flow, recipes build the source code and generate binary packages such as def file. The root file system and SDK are generated by installing the such generated binary packages. And we added a hook to hook in the default packaging function. This hook embeds the additional metadata into the binary packages. For example, license or source code name and so on. We also added another hook into the recipes that generate the root file system and SDK. This hook just generates a summary file from metadata in binary packages installed in the target image. And this is the samples of the summary information. The installed packages are listed in the last column in the package name. And each row has information about packages. These features can save some times to generate such a summary information in the product development. So I'd like to summarize this presentation. I explained about shared embedded abstract of the shared embedded distribution and for its devies. Devies intended to provide, especially the long-term maintenance. And this slide focused on the new features. For example, the package management with the DPKG and apt and the tag-based source code which end built. This is a function to reproduce an old image, release image using the git rebuild tag. And the last one is a summary generation. It automatically generates summary information about the root file system in the SDK. This is the current development state of the Debbie. The base YoctoProject version is upgraded to 2.2 development version. And the current version is also upgraded to the latest LTS and the LTSI. And some new VSP and recipes are also added. And about future works, we need to keep the following updates of Pocky and Debian. I am my understanding the YoctoProject 2.2 will be released as a stable version soon, at the end of October. So we need to follow with a newer version. And also, we need to support more embedded boards. And we'd like to improve the build time for upgrading target images, because we always need to bit bake and build all required packages to update some software every time. It takes too much time. So we'd like to improve the time. And there are related interesting work already presented in this embedded Linux conference. The first one is a generate Linux image from the Debian binary packages with bit bake. And it uses bit bake, but don't build from the source. All applications and customized packages built in the Debian's change route. And bit bake is used as some tools to generate the binary. No, generate target root file system. And the second one is LB. LB also generates the Linux image based on the Debian binary packages. And all specification about the root file system is described in XML file. So it's very interesting and easy to trace. And the last one is smart package managers. This provides a tool to install and install pre-built packages built by the bit bake without rebuilding a lot of packages. There are several similar approaches that use the Debian distribution currently. And I think we should collaborate with them and find out better ways about the package management. And then we are trying to, in the research level, we are trying to generate the recipes automatically from Debian loops to save times to create recipes. Because creating recipes also takes times and costs for the maintenance. So we'd like to find some efficient way to create recipes. And the last one, we also need to integrate the Debian with LTSI testing environment named Fuego. We'd like to contribute to this project by providing some test cases for the Debian and Debian and or providing some other useful frameworks. So we are waiting for your feedback. The features explained in this slide are just examples. If you have additional issues about the long-term maintenance, please let us know. And we'd like to consider adding more features to solve such issues. So let's choose first. This is the end of my presentation. And do you have any questions? Toolchain is also based on the Debian source code. And meta-toolchain in the POKI generates cross-toolchain from the upstream source code. But if you enable the meta-debian, the BitBake generates toolchain only using the Debian source code. But meta-data to generate SDK comes from the POKI. Only the source code is based on the Debian. Yes? Can you use Debian repositories once everything is set up? Debian repositories? To get packages. Do you mean can we install the binary packages from the Debian repositories? Currently, some packages can be installed. But not tested. And for example, the package VC is very simple packages, very simple commands. It depends on only libc. Such simple packages can be installed into the Debian directory if these architectures are the same. But some other complicated packages, maybe you cannot install because the meta-data in the Debian's binary packages might conflict with our binary packages currently. But I think there is some possibilities to reuse some simple packages by installing from the Debian repositories to development purpose. The recipe generation. Yeah. We're very new for that because we did that manually. Manually? Yes. I just want to know how this can be done. Yes. It is still in research levels. But I already mentioned we basically use the same command and options as the Debian rules files in our recipes. So some commands or some basic dependency information can be found in the Debian rules file or Debian control files automatically by creating some script to pass. But yeah, I also think it's too difficult to automate all of the process to generate the recipes. But I think we can automate the generating based of the recipes and then modify something by our hand. For example, about the settings for the cross-compiling. Yeah. Currently, we are creating the recipe from nothing. So it takes too much. Thank you very much. Considered you modules in order to avoid the Debian repositories? Sorry. Fat tools. Git, Git. What? Superdue. Git, Git, Superdue. Git modules. Yes, you can. Sorry. Which tools? Git, Git modules. Yeah, we just. We just simply use only Git command. Yeah, this is the Git command. No dependencies on other modules. Yeah. Do you hope your different functionality, I mean, do you just change the source URI of the upstream target with the Debian one and just build from that? Or you are using also the metadata from Debian? Yeah. We combat the old Debian source code from the app and from the turbo to the Git repo to get it fast. Then you use it. Do you use some of the infrastructure that Debian is putting in its package, I mean, the metadata of the Debian package, or just picking the target that Debian has and the patches that Debian uses for maintenance and just pick that, put together, and build the source from there? How many packages do you cover? For example, you are covering all the recipes that are in the Bokeh repository, or something like Qtify for these kind of packages that are in other diodes? The list is just dependent on our request. Yeah. Currently, the number of recipes is more than 300 or 400. So probably Bokeh and MetaPenembedev recipes, but not something like MetaQtify for all the layers with graphical things. Currently, we don't touch any BB files in the MetaOpenembedev course. So what do you mean is, for example, do you have recipes to pick Qtify libraries from Debian, or do you just cover, I don't know, maybe command line applications, or? Sorry, could fetch? The question is, do we have libraries for the graphical recipes, recipes for, for example, Qtify or Qt4? Yeah. I see. About Qt, we are currently still implementing the recipes for the Qt. And about X environment, we already switch some very tiny recipes. We are integrating new recipes as soon as you need them. But so there is no, I mean, a roadmap. So in this version, we are going to support up to here. And in this other version, we are going to support up to here. Yeah. Because of these destinations, because of just our requirements, we're trying to make the name and doing the terms and we're not so big community. So our main purpose for using this kind of stuff is mainly for the controller. Yeah, that controller doesn't reach a variant for the brush cut stats. That is why we try to do that, but not strongly for some of the brush cut stats. Yeah, thank you very much for the question. Do you have any other questions? OK, oh, yes. Up to repository is our package management. This one. You fetch your upstream sources, the devian sources, then you build the devian packages and you put these devian packages to an app repository. And then from this app repository, the root effect is generated. Is it correct? Yeah, all of this one is in the build environment. And all of them are generated by BigPake. Yeah. So this is done in every build environment? Yes. In the build directories of the Pocky, Pocky and Metal Evian. Repository automatically, in the fetch rules, whether the binary package is already available, then you would solve your rebuild problem, right? This is the way we want to do the CPSR. So we want to put the packages not into the local app repository, but on the server repository. Yeah. And then check in the fetch rule of every source package whether it was already compiled and is available in the central app repository. And in this way, we would avoid the recompilation of the stuff that was compiled or in previous builds. Yeah. This is what we want to do, we have to adjust. Yes. Now, currently, the package management functions of the package management from the Pocky are available, currently. But we like to provide and implement more features about management of such binary packages in the root file system, the target environment, and the build environment. So I think there are a lot of hints in another project such as either or every. Thank you for questions. Yeah. This works for you today for the one you have. The question was whether you can share this. Yes, you can share it. It's somewhere in the local project. Any other questions? If you have more questions, please come here and talk with me. So thank you for attending this presentation.


I think there's going to be a lot of value to be had on the Minnesota side of things, particularly in terms of Kirk Cousins, who I think might be just kind of an afterthought on this slate overall. But I like Cousins quite a bit. What are your first thoughts? I like Kirk Cousins a lot too. He's $7600, which means that he is tied with Tom Brady for the cheapest quarterback on the full four game, cheapest starting quarterback on the full four game slate. Tasting those a tight end if you want to count him. But Kirk Cousins is interesting because I know that we had this narrative in our head about how bad Kirk Cousins is in big spots. And we have this narrative too that the offensive line is going to struggle. That very well could happen because they're on the road in a really tough environment and bad lines don't travel, but the Saints are not fully healthy. And this has gone kind of overlooked because they haven't played good opponents recently, but they don't have Sheldon Rankins and Marcus Davenport. And if you look at the quad edge and look at their splits with and without Rankins this year, without Rankins on the field, they allow 4.65 yards per carry and 8.15 yards per pass attempt. It is 3.57 and in 6.11 with him out there. That is a massive loss and that doesn't even account for the time that he has missed with Marcus Davenport out because again, the teams they played are the Titans with no Derek Henry and then the Panthers with Will Greer slash Kyle Allen. So it hasn't mattered that they've missed those guys, but now against a Vikings team that is again fully healthy for the first time since week 6, that's really good for Kirk Cousins. And again, he's really cheap. So I with you, I think that there are paths to total destruction and oblivion for Kirk Cousins, but there are also paths to a really good game. And so for $7,600, I think he's really fun as long as you are okay with the floor being pretty bad. Yeah, I mean, the floor is bad. But if you look through his game log, I mean, so three games ago, 242 yards, one passing touchdown, you know, shy of 14 Fandal points and all three of these actually. So 242 yards and 207 and 122, one touchdown in each of them, again, hasn't broken 14 Fandal points in any of those past three games. And it's been quite some time since Kirk Cousins really turned things around early in the season back in like week five. So I think that he's well out of the mind of the common or just even, I mean, I overlooked Kirk Cousins until I really thought about it. Yeah. So I think he's going to be kind of off the radar. He's a road underdog. You mentioned the concerns, but I mean, he's fourth in passing that expected points per dropback since week five. He has four games against top half past defenses, 234 yards, not great, but 2.3 touchdowns, well above average passing efficiency in that split. I think getting Dalvin Cook could hurt his touchdown equity, but I think it's also Dalvin Cook's kind of good enough to boost the offense. He's one of the few running back. So I actually feel that way. Adam Thielen's coming back. I mean, he's been back for about a game and a half really in terms of snaps.  And I think that Kirk Cousins is one of the more interesting plays in the full slate. I fully agree. And we'll definitely be diving into Drew Brees too. I like Drew Brees a lot as well.