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Sturgeon's House

Collimatrix

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Everything posted by Collimatrix

  1. News about the Carmel has been trickling out for a while now. Or, at least the news that it existed. This looks like it has a polymer receiver rather than an extruded aluminum receiver, so there's that. Other than that, I don't really see anything that sets it apart from the crowd.
  2. The total sectional density is reduced, and also more of the axial momentum of the projectile turns into radial momentum:
  3. OK, time to look at the current and potential future armor of the Cascadian Entity's "Norman" tank. Sadly, ink supplies of the official Comic Sans typeface ran out, so we had to switch to Times New Roman for the remainder of this communique: Her Gracious and Serene Majesty Queen Diane Feinstein the VIII has charitably appropriated more earth conscious ink for this post The Norman has 8-10 degrees of gun depression, so it probably gets shot in the turret a whole lot. Any armament that cannot reliably penetrate the turret can't really be said to reliably kill it. We know that the existing Norman has a turret array of 50mm base RHA, 150mm of bolt-on RHA (sitting on a rubber mounting surface, which is assumed to have negligible impact here), a 100mm air gap, and 60mm of HHS on top of that. Running the equation backwards; (50 + 150) x 1.1 +60 x 2, we get 340mm vs HEAT, and 330mm vs KE. But the original Norman submission was very clear that this is a temporary expedient: Ruh Roh. So, there will be a 50mm base, a ~250mm pocket filled with NERA (let's assume it's similar to Californian H-NERA, since that is the most similar to the T-72B), 60mm HHS and light ERA on top of that for this planned upgrade. What we would really like to know is the angle of the angle of the armor plates within this array. In general, we can assume that the Cascadian armor scientists aren't stupid. Furthermore, they operate within a sane and reasonably effective management structure, which goes a long way to explain the recent defections. The optimal obliquity for H-NERA is quite high. Furthermore, the spacing requirements for H-NERA are large, with 54mm of distance between the sandwiches required, as measured normal. If the bulge zone overlaps with the armor box a little at the edges, that's probably not a problem because the edge of NERA arrays don't really work correctly anyways. Therefore, as a simplifying assumption, the arrays will reasonably run all the edge of the box they live in until their corners touch. The limit on plate obliquity within the box will be the angle at which the gap between the layers of H-NERA are wide enough that a projectile could pass between them without hitting one. Or rather, a bit less than this, because, again, the edges of a NERA array don't really do anything. Using a quick sketch in a CAD program my 1337 trig skills, I determine that the armor can be at up to 61 degrees from the vertical before such gaps appear. But realistically, it's going to be a bit less than that, so that the ineffective edges of the H-NERA overlap a bit more. Let's say 57 degrees from the vertical. There is also the question of whether the strike faces of these arrays will be tilted up or tilted down. Tilted up seems more likely to me because, although this sacrifices effectiveness against plunging fire, it increases effectiveness against direct fire when hull down. Single-layer L-ERA will probably be placed at maximum practical obliquity to get the most performance out of a single layer of protection. Let's say 70 degrees, and assume that any containers for this ERA will have negligible ballistic effect. So, inside to out that's 50mm RHA, H-NERA inclined at 57 degrees, 60mm HHA, L-ERA inclined at 70 degrees: I get that such an array protects 393mm vs KE and 749mm vs CE.' And that's just the planned upgrade. If they lop off the somewhat inefficient leading HHS and expand the array out to where it starts to be a problem for driver's hatch clearance, they can easily get arrays north of 450mm vs KE and 1000mm vs CE. So, getting a gun big enough to actually force the Cascadians back to the drawing board is non-trivial. So, with that out of the way, I have two questions: 1) What are the parameters for gas turbines? 2) What are the parameters for PELE rounds? The DM-33 derivative PELE round has 1/3 the penetration of the APFSDS round it's based on. Does 1/3 penetration seem like a reasonable multiplier for PELE rounds?
  4. Sure, although the magazine explosion can't have helped. Magazine explosions seem to have been very reliable ship-killers.
  5. The AP bombs were indeed low in HE fraction. The early ones were re-purposed battleship shells. I'm thinking that they're generally scarier than other bombs though. The record of killing ships in WWII by dropping bombs down onto them is quite poor. The record of killing ships in WWII by torpedo attack is quite good (provided said torpedoes actually worked; the USN was just being sporting by using garbage ones). "Dive bombers let in light, torpedo bombers let in water." So, I'm thinking that an AP bomb that stabs all the way through the ship has much better potential to act like a torpedo.
  6. *Looks around carefully to make sure that no auditors are in the room* *Checks the room carefully for SeaOrg bugs (which are easy to locate because they are clearly labeled "SeaOrg")* OK, just pointing out that if you make a gun that just barely meets Her Serene Majesty's requirements, it can't actually kill the Norman. Her Gracious and Serene Majesty doesn't actually know anything about tanks. Per the OP, the Norman has 330mm of protection against KE, and per the final post from the previous competition, that was clearly intended as an interim and easily removable armor array to be used until a proper composite armor array could be supplied instead. For 330mm of penetration at combat distances with full caliber AP, you're looking at something a bit more powerful than the M58, and ideally with better-designed shells.
  7. According to this presentation, the monolithic titanium armor is above the gunner's primary sight "doghouse," the blowoff panel covers, various and sundry covers for the NBC system, and "internal armor." None of those are integral to the vehicle hull. I've read in a few places that some versions of the T-90 also use titanium NERA. Both of these suggest that titanium alloys are efficient materials to use in NERA arrays. Why this should be eludes me. Titanium as a monolithic armor material is... rather mediocre.
  8. An op-ed from some years ago; reiterating that node naming is misleading, and doesn't really mean much. New video from Coreteks, predicting that some time within the next two years there will be hardware-level automated conversion of single-threaded sequential code into more parallelizable code. Apparently there are significant developments in this area lately:
  9. The Japanese had those really fearsome 800kg armor-piercing bombs, but I can't find any references to them hitting carriers. They seem mostly to have been used against stationary targets as during the Pearl Harbor and Darwin attacks.
  10. OK, here is some supplementary material: This video is clearly intended for a lay audience, which is good. I really don't "get" this computer hardware stuff to the degree that I get some other technology. One thing that this video clarifies that I had sort of vaguely understood is that the nanometer sizes in manufacturing jargon are just marketing. They refer approximately to the size of the manufacturing node, but there's no real reason to believe that, say, Intel's 10nm stuff is actually 43% larger than AMD's 7nm. They are probably broadly comparable. This video from an AMD higher-up also gives an overview of the recent trends in chip technology, albeit slanted towards server-type hardware. At 17:40 he discusses CPUs and GPUs baked into the same chip.
  11. Another post-mortem of Anthem: Interestingly, this one does not think that EA drove most of the bad decisions.
  12. Holy shit. That's one way to make sure you hit the ground pressure requirement.
  13. @Silah Report, you got anything to add to this?
  14. What a Long, Strange Trip it's Been PC gaming has been a hell of a ride. I say "has been" both in the sense that exciting and dynamic things have happened, but also in the sense that the most exciting and dynamic times are behind us. No other form of video gaming is as closely tied to the latest developments in personal computing hardware, and current trends do not suggest that anything dramatically new and exciting is immediately around the corner. Indeed, fundamental aspects of semiconductor physics suggest that chip technology is nearing, or perhaps already on a plateau where only slow, incremental improvement is possible. This, in turn, will limit the amount of improvement possible for game developers. Gaming certainly will not disappear, and PC gaming will also not disappear, although the PC gaming share of the market may contract in the future. But I think it is a reasonable expectation that future PC game titles will not be such dramatic technological improvements over older titles as was the case in the past in the near term. In the long term, current technology and hardware design will eventually be replaced with something entirely different and disruptive, but as always it is difficult, maybe impossible to predict what that replacement will be. The Good Old Days The start of the modern, hardware-driven PC gaming culture that we all know and love began with Id Software's early first person shooter titles, most importantly 1993's Doom. PC gaming was around before Doom, of course, but Doom's combination of cutting edge graphics technology and massive, massive appeal is what really got the ball rolling. Doom was phenomenally popular. There were, at one point, more installs of Doom than there were installs of the Windows operating system. I don't think there is any subsequent PC title that can claim that. Furthermore, it was Doom, and its spiritual successor Quake that really defined PC gaming as a genre that pushed the boundaries of what was possible with hardware. Doom convincingly faked 3D graphics on computers that had approximately the same number-crunching might as a potato. It also demanded radically more computing power than Wolfenstein 3D, but in those days computing hardware was advancing at such a rate that this wasn't really unreasonable. This was followed by Quake, which was actually 3D, and demanded so much more of the hardware then available that it quickly became one of the first games to support hardware acceleration. Id software disintegrated under the stress of the development of Quake, and while many of the original Id team have gone on to do noteworthy things in PC gaming technology, none of it has been earth-shaking the way their work at Id was. And so, the next important development occurred not with Id's games, but with their successors. It had become clear, by that point, that there was a strong consumer demand for higher game framerates, but also for better-looking graphics. In addition to ever-more sophisticated game engines and higher poly-count game models, the next big advance in PC gaming technology was the addition of shaders to the graphics. Shaders could be used to smooth out the low-poly models of the time, apply lighting effects, and generally make the games look less like spiky ass. But the important caveat about shaders, from a hardware development perspective, was that shader code ran extremely well in parallel while the rest of the game code ran well in series. The sort of chip that would quickly do the calculations for the main game, and the sort of chip that would do quickly do calculations for the graphics were therefore very different. Companies devoted exclusively to making graphics-crunching chips emerged (of these, only Nvidia is left standing), and the stage was set for the heyday of PC gaming hardware evolution from the mid 1990s to the early 2000s. Initially, there were a great number of hardware acceleration options, and getting everything to work was a bit of an inconsistent mess that only enthusiasts really bothered with, but things rapidly settled down to where we are today. The important rules of thumb which have, hitherto applied are: -The IBM-compatible personal computer is the chosen mount of the Glorious PC Gaming Master Race™. -The two most important pieces of hardware on a gaming PC are the CPU and the GPU, and every year the top of the line CPUs and GPUs will be a little faster than before. -Even though, as of the mid 2000s, both gaming consoles and Macs were made of predominantly IBM-compatible hardware, they are not suitable devices for the Glorious PC Gaming Master Race™. This is because they have artificially-imposed software restrictions that keep them from easily being used the same way as a proper gaming PC. -Even though they did not suffer from the same compatibility issues as consoles or Macs, computers with integrated graphics processors are not suitable devices for the Glorious PC Gaming Master Race™. -Intel CPUs are the best, and Nvidia GPUs are the best. AMD is a budget option in both categories. The Victorious March of Moore's Law Moore's Law, which is not an actual physical law, but rather an observation about the shrinkage of the physical size of transistors, has held so true for most of the 21st century that it seemed like it was an actual fundamental law of the universe. The most visible and obvious indication of the continuous improvement in computer hardware was that every year the clock speeds on CPUs got higher. Now, clock speed itself isn't actually particularly indicative of overall CPU performance, since that is a complex interplay of clock speed, instructions per cycle and pipe length. But at the time, CPU architecture was staying more or less the same, so the increase in CPU clock speeds was a reasonable enough, and very marketing-friendly indicator of how swimmingly things were going. In 2000, Intel was confident that 10 GHZ chips were about a decade away. This reliable increase in computing power corresponded with a reliable improvement in game graphics and design year on year. You can usually look at a game from the 2000s and guess, to within a few years, when it came out because the graphical improvements were that consistent year after year. The improvement was also rapid. Compare 2004's Far Cry to 2007's Crysis. And so, for a time, game designers and hardware designers marched hand in hand towards ever greater performance. The End of the Low-Hanging Fruit But you know how this works, right? Everyone has seen VH1's Behind the Music. This next part is where it all comes apart after the explosive success and drugs and groupies, leaving just the drugs. This next part is where we are right now. If you look again at the chart of CPU clock speeds, you see that improvement flatlines at about 2005. This is due to the end of Dennard Scaling. Until about 2006, reductions in the size of transistors allowed chip engineers to increase clock speeds without worrying about thermal issues, but that isn't the case anymore. Transistors have become so small that significant amounts of current leakage occur, meaning that clock speeds cannot improve without imposing unrealistic thermal loads on the chips. Clock speed isn't everything. The actual muscle of a CPU is a function of several things; the pipeline, the instructions per clock cycle, clock speed, and, after 2005 with the introduction of the Athlon 64X2, the core count. And, even as clock speed remained the same, these other important metrics did continue to see improvement: The catch is that the raw performance of a CPU is, roughly speaking, a multiplicative product of all of these things working together. If the chip designers can manage a 20% increase in IPC and a 20% increase in clock speed, and some enhancements to pipeline design that amount to a 5% improvement, then they're looking at a 51.2% overall improvement in chip performance. Roughly. But if they stop being able to improve one of these factors, then to achieve the same increases in performance, they need to cram in the improvements into just the remaining areas, which is a lot harder than making modest improvements across the board. Multi-core CPUs arrived to market at around the same time that clock speed increases became impossible. Adding more cores to the CPU did initially allow for some multiplicative improvements in chip performance, which did buy time for the trend of ever-increasing performance. The theoretical FLOPS (floating point operations per second) of a chip is a function of its IPC, core count and clock speed. However, the real-world performance increase provided by multi-core processing is highly dependent on the degree to which the task can be paralleled, and is subject to Amdahl's Law: Most games can be only poorly parallelized. The parallel portion is probably around the 50% mark for everything except graphics, which has can be parallelized excellently. This means that as soon as CPUs hit 16 cores, there was basically no additional improvement to be had in games from multi-core technology. That is, unless game designers start to code games specifically for better multi-core performance, but so far this has not happened. On top of this, adding more cores to a CPU usually imposes a small reduction to clock speed, so the actual point of diminishing returns may occur at a slightly lower core count. On top of all that, designing new and smaller chip architecture has become harder and harder. Intel first announced 10nm chip architecture back in September 2017, and showed a timeline with it straddling 2017 and 2018. 2018 has come and gone, and still no 10nm. Currently Intel is hopeful that they can get 10nm chips to market by the end of 2019. AMD have had a somewhat easier time of it, announcing a radically different mixed 14nm and 7nm "chiplet" architecture at the end of 2018, and actually brought a 7nm discrete graphics card to market at the beginning of 2019. However, this new graphics card merely matches NVIDIA's top-of-the-line cards, both in terms of performance and in terms of price. This is a significant development, since AMD's graphics cards have usually been second-best, or cost-effective mid-range models at best, so for them to have a competitive top-of-the-line model is noteworthy. But, while CPUs and GPUs are different, it certainly doesn't paint a picture of obvious and overwhelming superiority for the new 7nm process. The release of AMD's "chiplet" Zen 2 CPUs appears to have been delayed to the middle of 2019, so I suppose we'll find out then. Additionally, it appears that the next-generation of Playstation will use a version of AMD's upcoming "Navi" GPU, as well as a Zen CPU, and AMD hardware will power the next-generation XBOX as well. So AMD is doing quite well servicing the console gaming peasant crowd, at least. Time will tell whether the unexpected delays faced by their rivals along with the unexpected boost from crypto miners buying literally every fucking GPU known to man will allow them to dominate the hardware market going forward. Investors seem optimistic, however: With Intel, they seem less sanguine: and with NVIDIA, well... But the bottom line is don't expect miracles. While it would be enormously satisfying to see Intel and NVIDIA taken down a peg after years of anti-consumer bullshit, the reality is that hardware improvements have fundamentally become difficult. For the time being, nobody is going to be throwing out their old computers just because they've gotten slow. As the rate of improvements dwindles, people will start throwing out their old PCs and replacing them only because they've gotten broken. OK, but What About GPUs? GPU improvements took longer to slow down than CPU improvements, in large part because GPU workloads can be parallel processed well. But the slowdown has arrived. This hasn't stopped the manufacturers of discrete GPUs from trying to innovate, of course. Not only that; the market is about to become more competitive with Intel announcing their plans for a discrete GPU in the near future. NVIDIA has pushed their new ray-tracing optimized graphics cards for the past few months as well. The cryptomining GPU boom has come and gone; GPUs turn out to be better than CPUs at cryptomining, but ASICs beat out GPUs but a lot, so that market is unlikely to be a factor again. GPUs are still relatively cost-competitive for a variety of machine learning tasks, although long-term these will probably be displaced by custom designed chips like the ones Google is mass-ordering. Things really do not look rosy for GPU sales. Every time someone discovers some clever alternative use for GPUs like cryptomining or machine learning, they get displaced after a few years by custom hardware solutions even more fine-tuned to the task. Highly parallel chips are the future, but there's no reason to think that those highly parallel chips will be traditional GPUs, per se. And speaking of which, aren't CPUs getting more parallel, with their ever-increasing core count? And doesn't AMD's "chiplet" architecture allow wildly differently optimized cores to be stitched together? So, the CPU of a computer could very easily be made to accommodate capable on-board graphics muscle. So... why do we even need GPUs in the future? After all, PCs used to have discrete sound cards and networking cards, and the CPU does all of that now. The GPU has really been the last hold-out, and will likely be swallowed by the CPU, at least on low and mid range machines in the next few years. Where to Next? At the end of 2018, popular YouTube tech channel LinusTechTips released a video about Shadow. Shadow is a company that is planning to use centrally-located servers to provide cloud-based games streaming. At the time, the video was received with (understandably) a lot of skepticism, and even Linus doesn't sound all that convinced by Shadow's claims. The technical problems with such a system seem daunting, especially with respect to latency. This really did seem like an idea that would come and go. This is not its time; the technology simply isn't good enough. And then, just ten days ago, Google announced that they had exactly the same idea: The fact that tech colossus Google is interested changed a lot of people's minds about the idea of cloud gaming. Is this the way forward? I am unconvinced. The latency problems do seem legitimately difficult to overcome, even for Google. Also, almost everything that Google tries to do that isn't search on Android fails miserably. Remember Google Glass? Google Plus? But I do think that games that are partially cloud-based will have some market share. Actually, they already do. I spent a hell of a lot of time playing World of Tanks, and that game calculates all line-of-sight checks and all gunfire server-side. Most online games do have some things that are calculated server-side, but WoT was an extreme example for the time. I could easily see future games offloading a greater amount of the computational load to centralized servers vis a vis the player's own PC. But there are two far greater harbingers of doom for PC gaming than cloud computing. The first is smart phones and the second is shitty American corporate culture. Smart phones are set to saturate the world in a way desktop PCs never did. American games publishers are currently more interested in the profits from gambling-esque game monetization schemes than they are in making games. Obviously, I don't mean that in a generic anti-capitalist, corporation-bashing hippie way. I hate hippies. I fuck hippies for breakfast. But if you look at even mainstream news outlets on Electronic Arts, it's pretty obvious that the AAA games industry, which had hitherto been part of the engine driving the games/hardware train forward, is badly sick right now. The only thing that may stop their current sleaziness is government intervention. So, that brings us to the least important, but most discussion-sparking part of the article; my predictions. In the next few years, I predict that the most popular game titles will be things like Fortnite or Apex Legends. They will be monetized on some sort of games-as-service model, and will lean heavily if not entirely on multiplayer modes. They may incorporate some use of server-side calculation to offload the player PC, but in general they will work on modest PCs because they will only aspire to have decent, readable graphics rather than really pretty ones. The typical "gaming rig" for this type of game will be a modest and inexpensive desktop or laptop running built-in graphics with no discrete graphics card. There will continue to be an enthusiast market for games that push the limits, but this market will no longer drive the majority of gaming hardware sales. If these predictions sound suspiciously similar to those espoused by the Coreteks tech channel, that's because I watched a hell of a lot of his stuff when researching this post, and I find his views generally convincing. Intel's Foveros 3D chip architecture could bring a surge in CPU performance, but I predict that it will be a one-time surge, followed by the return to relatively slow improvement. The reason why is that the Foveros architecture allows for truly massive CPU caches, and these could be used to create enormous IPC gains. But after the initial boon caused by the change in architecture, the same problems that are currently slowing down improvement would be back, the same as before. It definitely wouldn't be a return to the good old days of Moore's Law. Even further down the road, a switch to a different semiconducting material such as Gallium Nitride (which is already used in some wireless devices and military electronics) could allow further miniaturization and speed ups where silicon has stalled out. But those sort of predictions stretch my limited prescience and knowledge of semiconductor physics too far. If you are interested in this stuff, I recommend diving into Coretek's channel (linked above) as well as Adored TV.
  15. I believe the "gun" is just a missile launcher, or it only fires low-impulse HE rounds at the most. So the breech should be quite small, and the recoil path quite short, so the driver can fit behind it.
  16. I was thinking about the 115mm D-68/2A21 gun in the earliest T-64s. You usually read this this was a simple modification of the 2A26 in the U-5TS/2A20 115mm gun in the T-62. Today when I was supposed to be paying my taxes or whatever, I had the sudden realization that this would not work. The T-62's 115mm fires conventionally cased ammunition. The T-64 autoloader uses two-piece ammunition. Separating the ammo into a section that holds the sabot and projectile, and a section that holds the propellant would allow the tank to fire once, and then the gun would be unable to reload. The case section holding the projectile would get stuck in the firing chamber, since it wouldn't be connected to the bottom section of case, there would be no way to extract it. So I double-checked Zaloga's book, and sure enough, there's a picture of the early 115mm two-piece ammo, and it's semi-caseless. So it's less of a two-piece 115mm, and more of a miniature 125mm.
  17. The trickiest thing about S-tank style configurations is ground pressure. The entire hull is sort of the turret, so the tank needs to be able to turn very, very quickly. The suspension is also how the gun elevates. This ends up requiring a fairly short contact length of the track. You can see in this: on page 25 that the S-tank has slightly higher ground pressure than tanks that were a lot heavier.
  18. So... just don't use full-caliber fins. And surely this changes a little if you have a tungsten head on a steel body.
  19. Yeah, the shorter penetrators mean that the fins have a lot less leverage for stabilizing the dart, which means that the fins are gigantic, which means draggy. The Soviet insistence on full-caliber fins didn't help either.
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