Posts by atropine blackout

To prevent 'lost' nukes, scientists suggest storing them in a hall of mirrors

A slight modification..

.. might help discourage hacking this system.

The interference pattern collected presumably depends on the frequency of the source, and if I understand the intent, they currently propose / use a constant RF frequency.

That being the case, then perhaps a long-period pseudo-random sequence producing a (possibly very wide ) range of radio frequencies could produce a series of interferograms that would be quite hard to predict / spoof if you didn't know the sequence of RF frequencies.

Provided you stay away from the worst water / atmospheric absorbers in the RF spectrum - tens of GHz up to THz I suppose - , you might also gain insights into the surface materials in the area being monitored - the drums / structure/ marker antennae will all have an RF absorption spectrum that will affect the interferogram for each frequency.

That might well make tampering / substitution just a bit harder.

I'm sure there are lots more variations on this theme; an interesting and unusual piece of work by the folks at the MPI.

US Air Force wants $6B to build 2,000 AI-powered drones

Re: They are getting part of a clue

Indeed.

As one Josef Stalin put it "Quantity has a quality all of its own" And the Russians had an awful lot of T34s.

In the same vein perhaps, the PLA, with their essential limitless supply of soldiers, allegedly noted during the Korean war "To win, we just need one more bullet than the other side has men"

China chokes exports of semiconductor secret sauces gallium and germanium

The view from Xinjiang

Its been a while since I was in Xinjiang but my memory is of an impressive transport infrastructure that seemed to be designed specifically to allow the PLA to quickly move to wherever the next 'local difficulty' appeared. (Think modern railways and miles and miles of smooth wide blacktops in a blisteringly hot empty desert).

Not unlike a 21st century version of General Wade's roads in Scotland built in the 18th century to help keep us Stroppy Jocks in order.

On the topics of racism and persecution, I'm not at all sure that either the Uyghur or Han Chinese folks would recognize the multicultural utopia you seem to be hinting at.

TSMC chips away at the competition with 2nm production set for 2025

Re: Nice

IIRC, modern wafer-based transistors are 3D devices and the headline size ( 2nm in this case) doesn't describe any physical feature of the transistor.

For a while (and maybe only for some vendors) I believe that the 3D 'size' related to an 'equivalent size' of an old-fashioned planar device.

Now I think the number is probably more of a a marketing thing.

While fundamental limits may well be looming on the horizon, I suspect that one thing that keeps AMSL / TSMC folks awake at nights is pondering the next step beyond EUV.

UK watchdog blocks Microsoft's Activision Blizzard acquisition

Whats good for Microsoft...

I listened (UK morning news) to Brad Smith holding forth on MS's unbridled enthusiasm for competition in the cloud gaming business, how the proposed merger would 'benefit everyone' (interspersed with his measured thoughts on how anti-business the UK currently is).

I'm not sure he did MS or himself any favors there, but also wondered if I was hearing faint echoes of the old 'Extend, Embrace Extinguish' approach .

Still, maybe the leopard has changed it's spots....

Google's claims of super-human AI chip layout back under the microscope

Re: Sorry Kahng, Goldie & Mirhoseini's AI work is legit BUT

The original paper may well be legit, but surely 'repeatability by a third party' is the generally accepted method of validating new work described in a paper?

In that context, I'd suggest that the authors' response, which seems to be along the lines of 'your mileage may vary', doesn't really cut it here.

Tech demo takes brain scan, creates a picture of what you're looking at

Somewhat off topic

A few years ago, prior to a bone scan I was injected with Technetium 99, a commonly used and fairly lively gamma tracer.

During the wait before scanning, I was chatting to the technician about research into decreasing the exposure time associated with short-lived radionuclides.

She told me that one of the big problems with very short-lived isotopes was transporting the material to hospitals . (this is cleverly avoided with Tc99 by shipping it as Molybdenum 99 which then decays to Tc99)

Apparently there are only a very few sites capable of making suitable short-lived nuclear agents, so you need fairly reliable shipping arrangements to avoid running out of half life.

In one case the journey from the Netherlands to the UK, including a traffic jam meant that an entire batch of Gallium had to be binned on arrival.

And for the curious - I measured my own gamma activity both at the time I was injected and 24 hours later - great happiness; the laws of physics held up.

A less than obvious limit

A few years ago, prior to a bone scan I was injected with Technetium 99, a commonly used and fairly lively gamma tracer.

During the wait before scanning, I was chatting to the technician about research into decreasing the exposure time associated with short-lived radionuclides.

She told me that one of the big problems with very short-lived isotopes was transporting the material to hospitals . (this is cleverly avoided with Tc99 by shipping it as Molybdenum 99 which then decays to Tc99)

Apparently there are only a very few sites capable of making suitable short-lived nuclear agents, so you need fairly reliable shipping arrangements to avoid running out of half life.

In one case the journey from the Netherlands to the UK, including a traffic jam meant that an entire batch of Gallium had to be binned on arrival.

And for the curious - I measured my own gamma activity both at the time I was injected and 24 hours later - great happiness; the laws of physics held up.

Sure looks like Beijing stole blueprints from chip fab world's ASML

Hard isn't impossible

China has long had a reasonably capable optical industry producing, for example, lasers and high efficiency dielectric mirrors, both of which you *really* need for EUV.

While pretty much every part of an EUV-based system is eye-wateringly hard to design, build and run , I can't really see why Chinese engineers wouldn't eventually get there.

That being the case, you'd imagine that any little 'how to' tidbits half-inched from ASML might be useful.

Boffins' beam forming kit opens the door to more realistic holograms

Reflections of Reflections

Just to amplify the previous comment, a well designed optical cavity, say 30cm long, and made with *very* high reflectance spherical mirrors (>99.999%), is capable of 'trapping ' light for tens (or more) of microseconds by repeatedly reflecting light back and forward along its axis.

As Paul Kinsler notes though, nothing is perfect and eventually the photons are either scattered or absorbed, even by the best of coatings.

There are a bunch of other practical problems (getting a useful amount of light and out of the cavity for example) but the system does work.

High performance cavities are still the basis of several types of laser and are used in 'ring-down' spectroscopy to detect trace (really, really tiny) amount of gas in the cavity.

Scientists pull hydrogen from thin air in promising clean energy move

Re: Storage ? Transport ?

Yes, in my experience, Hydrogen gas can be a fairly awkward fire / gas hazard to deal with.

It burns /may explode over a very wide range of concentrations in air - about 4 - 74%, but that can be affected by the energy of the ignition source.

For comparison, CH4 is flammable over about 5 - 15% gas in air, and needs to be around 10% for a good bang.

If the H2 does ignite , the flame is very hard to see - a *very* pale red, pretty much invisible to a human eye in sunlight (it shows up well fairly on camera but that's just the liveliness of Si sensors at 656nm).

Having seen a few mishaps over the years, the consequences of an H2 ignition event, together with the relentless enthusiasm with which H2 tries to escape its containment, would make me fairly wary of being around significant high pressure volumes.

On a related note, quite how H2 will be used as a (safe) replacement / dilutant for domestic natural gas may be interesting.

Resurrected Dundee Satellite Station to host quantum Optical Ground Station

Really?

As John 110 asks " have you ever actually been to Dundee".

The vast majority of folks travelling to/from production platforms and/or drilling / accommodation semi-subs use helicopters out of Aberdeen or Shetland (and have done since the seventies).

Dundee Riverside (DND / EGPN) sees some charters, GA and regular Loganair flights along with a very occasional helicopter.

Errol - the site of the satellite station - nowadays has only a few GA movements.

Re TFA, heartening to see the engineering folks out-maneuvering the bean-counters for a change .

UK gives military's frikkin' laser cannon project a second roll of the dice

Mirror Image

Mirrors used in big laser cavities are not quite like the ones in the average bathroom.

At least one of them - maybe both depending on how the laser cavity is arranged - need to reflect virtually *all* of the light they receive.

Never easy, but do-able in a clean laser lab (although using dynamic mirrors to hold the beam together looks like piling on the misery).

However, anyone working with beefy lasers is likely to be familiar with that sinking feeling after a less-reflecty bit suddenly appears on a mirror surface.. Time to open another box of mirrors.

And when you move the laser outside into a desert or marine environment.....

Still, there's always the spares and repairs business.

Not for children: Audacity fans drop the f-bomb after privacy agreement changes

I have a

Presumably there is a cunning plan, the likes of which Team Baldrick could only fantasize, lurking in here somewhere?

Either that or....

Toxic: Intel ordered to pay chip fab worker almost $1m after he was gassed at its facility in 2016

Re: "H2S is more toxic than HCN (Hydrogen Cyanide)"

H2S is only 'smellable' at low concentrations (typically a few tens of ppm).

At higher concentrations, it becomes very poisonous very quickly, as the regular death toll associated with drilling sites and enclosed spaces/ vessels confirms.

Quite why Intel thought that running the show without at least *some* H2S detection when they knew of the hazard is a touch surprising.

Incidentally, this means that, as happened to me in a Russian Refinery, you suddenly stop smelling background H2S and you don't have BA gear, your next move is neither obvious nor trivial. In our case we retraced our steps and avoided what turned out to be a fairly lively gas leak. Blind luck.

Oh deer! Scotland needs some tech smarts to help monitor its rampant herbivore populations

Moving Target

From the perspective of a tree-growing old bloke, with some practical experience of sending lead down-range, this problem isn't at all easy to fix. We already know (from tree damage, direct observation, dung counting, and so on) that we have too many deer in many areas in Scotland - the problem is one of control, not measurement.

Any 'credible predator' feeling peckish is probably more likely to take a swing at some local sheep rather than chasing deer for miles over rough terrain. That might get a few but probably not enough.

Shooting deer is not a particularly efficient way of controlling deer numbers. With sufficient firepower, equipment and determination, it can work well on open moorland, but is generally much less effective with deer species that prefer woodland cover (in Scotland that would often be Fallow and Roe deer).

Having been shot at, deer will typically 'up sticks' to another area and/or become entirely nocturnal. The whole enterprise then becomes *much* harder and more expensive.

And even in the event that SNH *do* get hold of some shiny new technology which churns out reams of accurate deer numbers (unlikely in the case of woodland-based deer), it is not at all clear what our next move would be.

Words like 'shark' and 'laser'come to mind, but then again.....

We are shocked to learn oppressive authoritarian surveillance state China injects spyware into foreigners' smartphones

Plus Ca Change

Having spent a bit of time in that part of China, I'd have to say that this level of repression is not really new - just different tech / better publicized. At that time (turn of the century), the roads in the area were some of the best in China - and were built *solely* for the benefit of heavy troop movements.

Even then we used Chinese-made burner phones; cash, rather than credit cards - you get the drift..... maybe still good advice.

Incidentally, part of the ongoing Han Chinese paranoia towards the Uighurs may stem from the fact that, unlike the Tibetans further South, the Uighurs are not (at all) given to turning the other cheek. In other (completely unreported at the time) news, the PLA and their nastier cousins, the Gong An, came off a decidedly poor second in several small encounters with Uighur groups in the desert West of Urumqi.

Didn't really help in the long run though, and its hard to see this ending well.

Geiger counters are so last summer. Lasers can detect radioactive material too, y'know

With current technology (and nothing dramatic on the horizon as far as I know), the powerful mid-IR laser - say in the 3..5 um region - needed for a longer usable range is a fairly non-trivial proposition.

An interesting paper but, as other folks have noted, there may well be an awkward gap between the model and reality.