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Tim Hughes

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Everything posted by Tim Hughes

  1. Long time since I did solid-state physics, but generally speaking these sort of simple observations are reasonable (this particular one is not, see below) only in ideal-cloud-cuckoo-physics world where all horses are spheres. In reality, things are always much more complicated. In any case, back in the land of make-believe, you only have to think about this for a short time to see that: </font> Atoms are less than 1nm across so there are going to be millions of 'layers' in either 80mm or 30+50mm plate.</font>The range of EM interaction between the 'layers' is unlikely (in the extreme!) to extend beyond 100 inter-layer separations (less than 10 seems much more reasonable).</font>This means the projectile has to penetrate, say, ten thousand of what you seem to regard as "hard" parts of the material, and either two or four of the "soft" parts.</font>It is unreasonable to assume that the difference between two and four "soft" penetrations is not going to be swamped by ten thousand "hard" penetrations. (Even if "hard" takes one unit of penetrativeness, and "soft" takes zero - i.e. the maximum possible effect - the difference is only that between 100,000 and 99,998.)</font>There is other physics occurring here. JasonC mentions shattering effects above.</font> PS. Manufacturing tolerances are going to add thousands of extra 'layers' of hard stuff in different places which would also swamp these edge effects. In this case, we would expect to see more variation across the 80mm plate than between 80mm and 30+50mm. AFAIK these variations are not seen.
  2. You'll be lucky (or at least will need to acquire some tools over and above the usual CD writing software)! SafeDisc is specifically designed to prevent you making copies.
  3. Looks like both sets of calculations are wrong when calculating the J/mm^2. The X-sectional area is pi*r*r (no factor of .5), but it looks like Jason has calculated pi*d*d (d = 2*r). So, for the 7.92mm ATR you get 9097/pi*(7.92/2)^2 = 184J/mm^2 And, for, say, the 50L42 507000/pi*25^2 = 258J/mm^2 (Of course, there could be a factor of 4 allowance for the fact that the projectile has slowed down by a factor of 2 travelling from the muzzle to the target.) In any case, the exact numbers don't matter. Since the factor of 4 is linear, comparisons are valid with either set of figures.
  4. That's a binomial distribution. You won't see two peaks. It'll look just like a normal distribution at first glance. The problem here is that the distribution is too flat to be normal or binomial - at least as they are usually understood. There just aren't any low or high tails. And the dip at '5' is so clear. I find it easier to believe the chance is something like 45% for 0, 1, 5, 7, or 8 rounds and 55% for 2, 3, 4, or 6 rounds with the probability split evenly within each group giving: </font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;"># shots probability 0 0.09 1 0.09 2 0.14 3 0.14 4 0.14 5 0.09 6 0.14 7 0.09 8 0.09</pre>
  5. I can do statistics at work with some plausability (I'm on GMT/BST). Running full screen CMAK might be pushing it a bit
  6. Looks real to me There are a number of sophisticated tools statisticians (and others) use to determine if an observation is significant. I haven't been a practicing physicist for 21 years now so I've forgotten it all. In any case, the data here isn't really useful for what you want. Are you even sure the distribution is normal and not binomial? Poisson? Completely random? See (for example) Does this data come from a normal distribution? for more ideas on checking - there's also the Kolmogorov-Smirnov test if you want to go that far (try Google). But just stuffing the data into OpenOffice and drawing a chart gives me severe misgivings about the normality of the distribution - it just doesn't look like it. If it's not normal then most high-school statistics aren't valid and speculation on the importance of the SD is close to pointless.
  7. You do the SD calculation *down* the columns, not across the rows. The calculation (assuming I haven't cocked-up somewhere) gives Series Mean SD 1(250) 3.96 2.2 2(376) 4.16 2.5 3(376) 4.29 2.4 Sum(1002) 4.16 2.4 Mean given to 2dp and SD to 1dp You should treat the results and their interpretation carefully because (a) the number of trials is still quite low (although with 1000 trials we should have random error down in the 3% range), and ( the distribution clearly isn't normal (consistent dip at 5), so the meaning of SD is not what one might expect.
  8. I have a friend who works at the IWM Duxford, he regularly drives tanks (apparently rather enjoyable) and had this to say on the subject of turning tanks when I asked (for other reasons): I believe some WWII tanks could do the "neutral turn" number, but maybe not.
  9. You might want to clarify that you are talking about CW brigades here (and it's already been noted above by JDS). If you mean US formations then it's a case of "Veni, Vidi, you talked rot".
  10. You might want to clarify that you are talking about CW brigades here (and it's already been noted above by JDS). If you mean US formations then it's a case of "Veni, Vidi, you talked rot".
  11. Come on BF, whoever writes the patch installer should make sure it works with CDV installations as well as BF ones. There is intelligent life outside North America. This is not rocket science, but it sure is annoying to all us CDV customers if it isn't done. At the very least it should be made very clear which folder is the one to select. It's been a while since I patched my installation but I remember it wasn't at all clear.
  12. If you see John, tell him he owes me turns!
  13. Interesting comment from Martin in an interview/panel discussion over at SimHQ (http://www.simhq.com/_all/all_009b.html) " Martin (Battlefront): So far, every anti-piracy scheme has been cracked sooner or later. Like you say it's a problem that will never go away. So the main purpose of such programs is to buy time for the publisher to keep his "first to market" advantage. Important for shelf distribution (otherwise retail will be reluctant to buy games from you to put on their shelf), but far less important for our distribution method. Which is why we have never used such programs. Let's also not forget that it is questionable how many people who play the pirated version of your game would turn into paying customers if you try to force them to. This isn't to mean that we condone piracy, but we try to counter it by making darn good games and hoping for support because people will want more of the good stuff, rather than wasting thousands of dollars on the attempt to force them against their will. " Emphasis added.
  14. Stuff to keep: 1) PBEM 2) Realism(?) over eye-candy 3) Straightforward/easy artillery system (for those of us who don't want to pre-plan the trajectory of individual shells) 4) WWII emphasis - don't compromise tanks/infantry/artillery for the sake of horses/flaming pigs/space lobsters 5) WEGO 5a) Did I mention PBEM? Things to change 1) PBEM - just two messages per turn please 2) Open up the file formats allowing 3rd party map design/scenario design/campaign management 3) SOPs - at least convoy movement 4&5) All the good stuff you've already told us about
  15. http://www.battlefront.com/discuss/ultimatebb.php?ubb=get_topic;f=23;t=010687;p=2#000038 "vehcile" Get a life.
  16. My background is quantum field theory rather than soil mechanics But the following comes to mind: The crucial issue for influencing the height and longevity of the dust cloud is the radius of the particles making it up. (Very loosely) the force pulling the particles down (gravity) depends on the mass, hence radius cubed, of the particles, whereas the force resisting this - air resistance - depends on the cross-sectional area, hence radius squared (also the velocity, but that's another story). So, the ratio of force down/force up is proportional to the radius. For large particles (say people, or cats) the force up is pretty well negligible for speeds less than several tens of metres per second and they accelerate downwards at the usual 9.81m/s^2. For small stuff with large area/mass ration, say a paper airplane, the force upwards can pretty well compensate for that downwards at even low velocity so the plane flies (rather than plummets as a sheep does). Back to dust clouds. One of the major determinates of particle size in earth/soil is the moisture content - wet stuff sticks together better as the water can act like an adhesive (again very simplified). Wet clods of earth thrown up by tracks will drop straight back down again with almost no air resistance. Fine grains of sand will return to the ground much more slowly. Similarly, any tendency of hot rising air to lift particles up is only going to be effective where the upwards force exceeds that of gravity - this will only be possible for small particles. Go to the beach, throw up a handful of dry sand from above the high water mark and a handful of the wet sludge from where the water is washing back and forth. The wet stuff comes straight back down unaffected by the wind (except if there's a gale blowing) whereas the dry stuff (a) falls back more slowly; and ( is easily blown downwind. I haven't checked, but (if Charles is doing his stuff) dust clouds should be a lot less pronounced when the weather is wet.
  17. PS. NSIS lives on SourceForge at http://nsis.sourceforge.net/
  18. I don't want *you* to do it - although obviously that would be better - I'm happy to do it if either: a) the installer you provide can take language and pathname arguments; or a list of the changed files and where they go was available. If (a) is either too hard or too much work (and I appreciate you may have a lot more important things to work on at the moment than making my life easy), then, presumably, you've got the list of files as you need it to build your own installer. Let me have that. I'd be more than willing to post the result - an installer for CDV customers using English at the least, one for everyone (BFC and CDV) in all languages if that was feasible. As a last resort I can always diff the original and patched trees (or just hold my users' hands).
  19. It's a patch to the batch for the patch I'd probably write an NSIS installer rather than risk someone not being able to run a batch file, or not having the patch executable for the batch file to run, or Saturn being in the house of Libra, or whatever. Users, eh. Who needs 'em ? (Of course, whoever writes the patch installer for BFC could look for the CDV registry entry if the BFC one isn't there and then (part of) the problem would go away. Or, better, CDV could stop messing about with where the damn thing installs and which registry entries it uses. But then what do I know? I only write software and installers for a living )
  20. Obviously I *really* meant </font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">CMAK_v103_Patch.exe /language English /location D:\Games\CMAK</pre>
  21. In the original thread about the patch which is now closed I said: and Madmatt responded With the context set, I'll continue. Matt, I agree with what you say, it's all there in the notes, but I'm trying to make it even easier for "my users". There's a (different) registry entry for CDV versions indicating the installation location and, in my case, all the users are English. So, I want to have a batch file or, better still, an installer (say one written using NSIS) that *automagically* sets the language to English and locates the installation directory from the registry entries and executes the BFC provided installer with that information ready provided so the user can't make a mistake. I want to be able to say something like </font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">CMAK_v102_Patch.exe /language English /location D:\Games\CMAK </pre>
  22. I'm the unoffical tech support for several of us who play CM. I'd like to be able to script the installation for the others so no human interaction is necessary. Can command line arguments be given to the installer to specify the language to use and the location to install to (we use the CDV version here in the UK) ? If not, can they be added for the 1.03 patch?
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