petschge

50 ms·

511.
by petschge 7y ago
I would suggest osmand. The basic version is free, you can download data state by state (country by country when you are traveling) so it doesn't need a data connection on the road (but online search is available if you do have a data
512.
by petschge 7y ago
Typically you pay $200 per semester in enrollment fees (bus ticket to the city included). And while private universities in Germany exists they are absolutely tiny compared to the public ones.
513.
by petschge 7y ago
Funny little detail that might interest you: Due to the presence of a large number of different fission products (with different half lifes), the drop does not really follow an exponential but is better described by P(t) = P_0 * a * (t^-0.
514.
by petschge 7y ago
While you are correct that it is less than the nominal heat output, we are still talking about 50MW a minute after shut down and 5MW one day after the shutdown of a 700MW reactor. So even a day after the shutdown you are able to boil of 2kg
515.
by petschge 7y ago
While dam break cost lives, there is crucial differences that are never mentioned by the pro-nuclear crowd on HN. 1.) Dam breaks devastate much smaller areas. So even if the human toll is the same, the amount of infrastructure lost is small
516.
by petschge 7y ago
They have done that and it got an award because it was new and cool, but that is not where the majority of cycles goes. That is spent on fluid codes such as Raptor, XGC or Flash and to some extend kinetic simulations with codes such as VPIC
517.
by petschge 7y ago
I doubt they are going to run much AI on that machine. The national labs mostly run "traditional HPC" workloads such as fluid codes that simulate (magneto)hydrodynamics in one way or another.
518.
by petschge 7y ago
That is true. But very few super computers track power consumption for different codes and do power aware scheduling. SuperMUC and IBM actually do a lot of research on this, because it is a rather new field in HPC.
519.
by petschge 7y ago
They might coordinate with TVA for transients (i.e. going from an idle machine to a full-machine run), but in normal operations these systems are at least 50% full. In my experience as a user these machines are more than 80% most of the tim
520.
by petschge 7y ago
That's right they are inconsistent with the combination of 1.) dark matter is the correct theory and 2.) they have the usual amount of dark matter for a galaxy of that size. Surprisingly this is does not make the theory of dark matter
521.
by petschge 7y ago
The fact that SOME galaxies are inconsistent with the theory of Dark Matter actually strengthens that theory. If the difference in rotation curves, the usual signature of dark matter at the galaxy level, from what GR predicts based on the m
522.
by petschge 7y ago
Ok, make it 14 instead of 10 then. That's a small correction. Filling the gaps on the other hand does not require a factor of two, but only 2 \pi / sqrt(27) or about 1.21. Multiplying the 14 with that gives us 17 instead of the 20
523.
by petschge 7y ago
I have thought about bandwidth, but that should only matter once you have a lot of customers.
524.
by petschge 7y ago
That does indeed assume a sphere. If you are curious about the geometry, maybe https://en.wikipedia.org/wiki/Horizon#Distance_to_the_horizo... can help. If you run the calculation the other way around, every satellite
525.
by petschge 7y ago
I do wonder a bit why why they need THAT many satellites. Assuming an orbit at 200 miles altitude, we have a horizon distance of about 2000 miles. Comparing the area of that 2000 mile radius ground patches with the surface of the Earth, we
526.
by petschge 7y ago
I actually do plan to update the tree as I insert additional particles in locations where the distance to the nearest neighbor is large.
527.
by petschge 7y ago
Typical full sized simulation runs contain between 100 million (1e8) and 100 billion (1e11) particles. Small tests while debugging might be as small as a few thousand particles (1e4). And tests of the code might only use one or two particl
528.
by petschge 7y ago
I do plasma simulations and recently had the problem of finding the distance to the nearest neighbor for every of the particles in the simulation. Doing that naively is O(n^2) and took hours even for small test problems. Building an R-tree
529.
by petschge 8y ago
Note that while inkscape SVGs do conform to the standard, they do contain extra information in their separate namespace to preserve UI information across save/restore cycles. One example would be layers. They are saved as standard comp
530.
by petschge 8y ago
Yes. And better students tend to want more rigor (or have more brain cycles left over for more rigor in the introduction of new but only tangentially relevant topics) than the weaker students, who are usually more happy to take something at
531.
by petschge 8y ago
In the first case you would get outright rejection (typically expressed as "why do we even need that" or "nobody can understand that"), in the latter at least the better students would ask question "why can we do th
532.
by petschge 8y ago
Well I did that. I also gave them a similar warning when I started using the dirac delta, because it is not a proper function and if you want to know more than "it eats integrals", you have to either view it as the limit in a seri
533.
by petschge 8y ago
Having tought classical mechanics I have to say, yes we do that (intentionally), but it is due to a lack of time and due to a lack of preparedness of the students. I have 16 weeks of instruction, with 2 lectures of 90 minutes each, to cover
534.
by petschge 8y ago
The other thing that is very obvious as an European currently living in the US is the insane amount of plastic associated with food. Hotel breakfast will be (even in relatively upscale hotels) on single-use styrofoam plates, with single-use
535.
by petschge 8y ago
To add on to this: The plastic bags in the supermarket are also typically too flimsy to be used as garbage bags, which was my standard way of using them when we still had plastic bags in Europe. Instead they are already full of holes by the
536.
by petschge 8y ago
Still the best solution for teaching complicated topics that have a compact notation.
537.
by petschge 8y ago
It is not just directly related deaths, but also the area of land made un-inhabitable and the duration for which it will remain un-inhabitable. And the fact that we have no workable way of dealing with the waste. Sure it only take a small s
538.
by petschge 8y ago
Pretty cool to see that boost admits that this is an issue and works on decoupling things. I look forward to see improvements here.
539.
by petschge 8y ago
Note that this is the fuel from the cooling pool of reactor building #3. The cooling pool of reactor building #4 has already been emptied. And the we are still not ready to remove the heavily damaged fuel from the reactor cores.
540.
by petschge 8y ago
And that is the main problem with boost. If you want any of it, you have to live with all of it.

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