namibj

Don't need global shutter just use a bit more math and IMU data with frequency in excess of the frame rate.

Make it work with the recording capabilities of a good modern phone and handle the compute in non-real-time.

There's also the potential of co-locating non-evaporative cooling with CO2-scrubbing using a strong KOH solution in the big cooling towers and regenerating the hydroxide with calcium hydroxide (regular process done in kraft process paper mills, though they use NaOH with slightly favoured properties over KOH). KOH is very hygroscopic; it does not have to be humid for a barely-still-liquid solution to actually dehumidify in the process.

Or, if that's too much effort for them, use e.g. LiBr or other such atmospherically-stable salt that can maintain humdity equilibrium with dry ambient air.

The reason for even involving a water-based solution at all is because you can spray it or at least run it over dense corrugation (sheets alternating orientation, but overall with the channels roughly pointed upwards) "packed beds" with free contact between the coolant and the air, instead of having to maintain a barrier layer between the two (typical car/computer radiators, but also AC coils), which notably saves you from even a potential for a there-required barrier layer to leak and from having to clean such a barrier layer. If you make the corrugations large enough and have some simple mesh filters in the intake path that you just roughly shake/rinse/blow/brush off every once in a while, you can prevent particles larger than a rice grain from getting to the coolant in the first place and wash/rinse all the sand grain and smaller dust particles down into the coolant sump where their densities are far better matched (than air vs. dust) and volume flow is much easier to handle/filter.

The big part of these is still that they don't require active fan ventilation to cool radiators, which would be a substantial increase in critical electrical power needed after a SCRAM to keep the core from melting down; vs. the passive evaporative cooling towers and the KOH/LiBr non-humidifying variant I mentioned.

It'd suffice for them to sign the transmitted information (audio and required timing metadata for the packet stream) and make you do the temporary recording on your side, transmitting it back to the provider once you hit the button, to let them handle the backup/safekeeping aspects for you.

The tin plasma source is the one we don't know how to reproduce; in contrast we know how to do it with an electron-syncrotron (though IIRC for the energies here it is technically practical to do with just a linac) and there are AFAIK several vendors that can provide you the hardware for such an accelerator; the know-how is distributed among many applied particle physicists all around the world; and the FEL hardware to make the actual EUV beam(s) is not high-tech compared to even the high-vacuum accelerator cavities.

The main difficulty of that approach is that physical constraints of field strengths (exceeding those would cause stray electrons to spontaneously free themselves from any vaguely conducting surfaces they are on, and fly around the accelerator, causing arcing damage, wasting energy, and disturbing the beam/beam-control-sensors), the thing has to be fairly large; also, building it with a bit more incremental power is a cheap upgrade (at least if done at design time of the accelerator) up to around a dozen EUV scanners worth of light output.

Complicated by that you ideally want redundancy to not have EUV scanner downtime just because the accelerator needs maintenance, so in practice you'd want like 3~5 accelerators each sized for 20~30 scanners in one building with EUV-routing-flexibility to have n+1 redundancy for the accelerators.

But those 40~120 EUV scanners, especially if you include the rest of the fab to actually run them in production, is a very large investment. Like, somewhere between 1 and 5 % of TSMC's market cap. Not under 2 aircraft-carriers (the big ones)... it's in no way a "low-risk" investment. But, back before GlobalFoundries gave up on the EUV race, a free electron laser was exactly what they were working on bringing to use for EUV litho (it's mostly a energy efficiency question around recovering energy from the electron beam after it was used to generate the EUV, and the substantial difficulties of efficciently redirecting the EUV from the source to the scanners, that's still open research with FEL illumination for EUV scanners).

You could give each one a diceware-eff-wordlist-like "ID" when they input where they want to go, perhaps have a "group" and "single" button/column per destination in the menu as well to inform the elevator if it's a group traveling together, and importantly have a fast-food-pickup-counter style dispatch screen up top visible from the waiting "hall", that assigns you a cab with an appropriate notice/heads-up period so you can make your way over to the assigned cab.

What battery technologies are banned??? While being good except for efficiency?

No the beam source we know how to create; it's just that the way to do so requires a factory sized machine that better be feeding 10~30 steppers or a pair for uptime/maintenance windows and then probably more like 50 steppers.

Free electron lasers are not hard at "mere EUV", and the accelerators to feed aren't either, it's just that an efficient setup requires recycling the beam which means bending it back which means a large (factory hall sized) accelerator at the beam energies needed for good EUV light.

My fine spice recipe writing scale (20g max, 20k count) consistently over years of me having it keeps it's magnitude calibration of the 10g reference to a single digit count, i.e., comfortably within +-0.1%.

Ofc there's auto-zero on start involved, but translated to a people bathroom scale that'd be "comfortably better than +-100g".

A precise bathroom scale just would want a bit more effort on drift prevention as a sample mass at this scale is rather unwieldy, and critically it'd need a toe-operated button to select that you've finished climbing onto the scale, upon which it starts averaging the load to progressively improve the weight measurement accuracy. I'd expect using a bounce-height-freefall-duration based length of timing uncertainty at the start and end of the averaging period to allow proper Bayesian uncertainty quantification of the shown result, say by displaying both the 10th and the 90th percentile on the display which grow closer as you wait while standing on it.

With some cleverness a compact calibration mass might be usable to calibrate absolute scale, transferring up to the "people" range using just a random assortment of stuff that fits on the platform, totalling around 10kg.

Because building the scale to be linear in response good enough for 20k count of resolution is pretty straight-forward.

The video codec does not care about VRR, it happily does it. If the receiving display can do VRR, it'll just work.

Stop insisting on Cat.6A (and related) copper cables for speeds beyond 1000BASE-T (maybe beyond 2.5G by now), just use dumb multi mode fiber it's way easier technology-wise and if you want power you can have that as well.

At distances where Cat.6A is even an option the demands on the fiber are very low. And it uses less power than the BASE-T PHY. The cable at least without integrated power is very thin as well, unless you can't respect it enough to not kink it, in which case you'd want a thicker one just to prevent you from being able to break the fiber.

Plus power and cooling.

A good chunk of 802 is not paywalled for individuals, notably at least 802.3 and 802.15.4, which I read good chunks of.

Those are Not where the tubes are SOTA.

The actual alternative is induction motors, which are just a bit less efficient than PMSM and otherwise basically the same. Except that the frequency fed to them isn't exactly proportional to speed.

They've been used to great success since we had the needed power electronics to drive the electric trains of Europe.

Yeah so the relationship between speed, power, frequency, size (both in the direction of primary flux excitation and in the direction orthogonal to both that and the movement), and torque at nominal values of current density (for a given conductor losses are proportional to the square or this value and to the total mass of that conductor in the machine; that's independent of any of the other scaling parameters; note this is absolute power not percentage) and peak flux limitations (core saturation, permanent magnet demagnetization), are sadly not trivial if you express them in a way that is even just _valid_ for the modern days where we can support electrical frequencies up to around a megahertz at scales up to around 100 kW, and even harder when you remember that core material has severe frequency dependence of it's limits.

E.g. for example for a given electrical frequency and decent radial flux synchronous machine, power density is quite static and torque density can actually be dialed quite freely from 2-pole machine (turboset in gas turbine running on the grid at 3600 rpm (or 3000 rpm outside NA and some Pacific Islands) to 40(+) (example deployed at Hoover dam, 180 rpm). At those higher pole counts, the center of the rotor is no longer electromagnetically active, because the magnetic field lines keep to a narrow ring only about as thick as each pole is wide. Unfortunately it's mechanically not that trivial to handle a cylindrical shell with a small air gap (this needs to be significantly smaller (about at least 10x) than the pole width) when using substantial torque and speed.

Circumferential velocity is practically limited by hoop strength of whatever the outer region of the rotor is made of, even if it's all very nicely balanced, because eventually the magnetic armature flux source (wires or magnets) will fly out.

Higher electrical frequencies limit the field winding core's magnetic permeability (magnetic field/force strength amplification relative to vacuum, for same electrical current) which hurts efficiency by dropping the useful mechanical power component of field voltage while the voltage resulting from the current (that needs to happen to cause the magnetic field in the direction of movement that causes the mechanical force) due to wiring resistance stays. (I think the permeability gives the ratio between voltage and current for otherwise identical mechanical load conditions and winding shape?)

Thinner wires have less fill factor because the insulation has to stay the same thickness as per-winding voltage stays, but magnetically inactive terminations are less wasteful (for losses and mass) when a decent number of effective turns (>>1, think >10~50 for most of the benefits) are used.

Note while the armature necessarily has an even number of poles in it's construction (north/south), the field is not forced to that.

Indeed, the iirc most smooth torque (under practical mechanical feasibility limitations and without undue sacrifice of efficiency) results from having a prime number (of field windings, in WYE-style connection) exactly one off from the armature pole count. Note that for low losses all these torque-smoothing techniques _require_ only a single electrically directly driven winding in each slot (per mechanical field pole) and with that only GCD(field_slots, (armature_poles / 2)) windings get to share an electrical half-bridge (one single wire going to a single voltage-output terminal on the electronics board; note mainstream BLDCs have 3 of these, classic fridge compressors have 2, and modern stepper motors (e.g. 3D printer) have 4).

Any time you have multiple windings driven by different electrical source voltages you're wasting heat in the winding because the lowest-loss would require all conductor in the slot to to perfectly evenly share current.

There's just one problem with that: you need a nearby slot with exactly opposite phase to even possibly use more than a single (half) turn of "winding" in the slot.

If the voltage is still enough to not loose too much in the connections, you can use transistors developed for efficiently powering modern computer chips from comfortable voltages like 12V, but even then a "winding" has to be much longer than an armature pole to mitigate the losses of spreading the return current sideways to where a slot carries the current in the reverse direction. Once the voltage at the transistor is over around 10V the benefits of more precise control of the field magnetization to the armature position (and how the shapes distort the field lines from anything that would look like a sine wave) could be useful. In theory that'd also provide direct access to electronically control the air gap (well, net force normal to the air gap "surface") which _could_ be an alternative to mechanical bearings for very thin-shell constructions. See maglev trains for a pretty practical application of using an electric motor to also levitate the "rotor" in a place where a mechanical bearing ("train wheels + bogies") performs poorly.

Actually large data centers at least if done in a vaguely alirack style architecture, can do this with a decent fraction of their nominal power for very little hardware cost, as reactive power and real power add up via Pythagoras (`apparent=sqrt(real^2 + reactive^2)`) to the apparent power (rms voltage times rms current, which is what the 60Hz electronics and 60Hz transformers care about). The first 10-ish % are nearly free.

And alirack style datacenters have large 3-phase converters between the grid and some 240 (nowadays often 350) V DC bus, with the battery banks directly (with just fuses and sometimes a little bit of balancing/nudging power (think 10% of battery power rating)) on the bus, and then the servers also directly consuming from that bus.

The large converters on the battery bus thus allow synthetically smoothing load transients to the grid using the batteries to smooth that power draw. This has just minor additional wear on the batteries and a small power efficiency impact from hitting through the batteries, both of which are easily paid by anything market-rate of providing that grid service. Because they already need the power electronics and batteries anyways, unlike a utility battery farm that at best can argue day/night load shifting of solar production as the reason for the electronics and batteries to exist.

In that same spirit it's also effective to put batteries on the DC bus (between MPPT and inverters) of large solar farms, because they need the electronics anyways and it's actually reducing the required inverter&transformer capacity of the solar farm by peak-shaving.

10+ MW voltage-source converters that can't do up to around 80% of their nominal capacity as mostly-reactive apparent power with stabilizing synthetic inertia scaled as desired/specified are a mostly software issue, stemming from lack of regulatory pressure incentivizing the engineering complexity of that.

Though if you want to do a smoothing action on real power flux you'll have to colocate battery capacity with the converter. Which to be clear is fairly cheap to do as long as you get compensated for the substantial frequency stabilization capacity this represents. I'm talking like 15~120 minutes at converter nominal AC power of battery capacity.

The first 10~20% of reactive power are almost free from the converter electronics, btw....

Isn't the problem with write back cache mode just due to the GPU being unable to invalidate cache lines in the CPU?

There are solutions to those worries.... https://epc-co.com/epc/products/gan-fets-and-ics/epc23102

You can also have two shunts per phase, one low side and one high side. The "hall" "shunts" are pretty good though.

Ehhh if it's just for looking and you don't have anything lidar just go for splats they're way better behaved, mostly because they don't need to understand a concept of "surface" they just understand "splat with spherical harmonics of view-dependant color".

Jules is heavily restricted in what it can do to your repos.

Dropping containers at the consumer end isn't that bad, at least when they're empty they're not that hard to move back on a truck and there are plenty of uses above scrap value for a container in seaworthy condition.

It's actually strange that we don't seem to have any system for just dropping containers at the destination until the contents have been processed, instead of the current system that essentially mandates unloading the container rapidly as soon as it shows up because an entire truck+driver is waiting for the unloading to complete.

For palletized loads it's easy to unload them into temporary space in the building they're delivered to, but not everything is palletized.

Plus tax no we can't tell you before you order.

Huh, what were you doing, buying Cisco/HPE, or trying to use fancy single mode optics for distances that DACs could do?

Also, dotsies[0]: 5 high 1 wide, no horizontal spacing for kerning, ascii-space is just the all-white "character", letters (text) only and made more for visual density than actual pixel scarcity.

[0]: http://web.archive.org/web/20171103012446/http://dotsies.org...

Well in theory the base math is indeed the same; unfortunately though the "randomly chosen" part of shamir's secret sharing is fairly important to the security because information theoretic security of the scheme requires each fragment to be as large as the original secret by way of essentially including a desired count of random data blocks to the original before applying the reed-solomon-like erasure coding to it where now enough fragments to reconstruct the secret plus all random blocks have to be combined. Also the way of usage of the erasure code has to be selected to not be leaking information but that's more of an issue of not picking a bad way of how to implement the basic concept here. Basically just a case of "do follow the instructions to shamir's secret sharing, don't do something different just because it's a popular way of implementing reed-Solomon".

Yes, you can just GF(256), but if you're worried I'd also just use a prime field instead.

Well it should be unconstitutional for any law or government ordinance to demand compliance with any standards that are pay-to-copy.

Arguably the government should publish a blessed magnet link of a blessed torrent file per each field of standard. Probably with the padding files used to make each PDF individually hash-checkable.

If nothing else it's a practical way of declaring what standard version is the legally significant one. It's usable without actually sharing any of the PDFs anyways.

Yeah you can start by not building _more_ in the flood plain. And if you do, then don't build architecture that is incapable of just accepting the temporarily higher ground water. We know how to basement just make the basement high enough to tower over the flood. Oh, no cheap ground-level storefront windows? Welp, guess those have to be elevated above sufficiently voluminous drainage channels (the former streets).

In Germany it seems to have moved to the 3D photogrammetry data for anything with pixel sizes smaller than a car; is that maybe also the case for Paris?

I do understand that it's sad they don't calculate orthographic images from that to replace their satellite views in these areas though; full 3D is severely more resource intensive on the client after all.