...is pretty much what the yellow warning label on one of the optical benches at the NPL says:
"Warning : Do not look into the laser with your remaining eye"
32 posts • joined 1 Nov 2012
...is pretty much what the yellow warning label on one of the optical benches at the NPL says:
"Warning : Do not look into the laser with your remaining eye"
The nearest gorilla in the room isn't the technical one (the "1 atom transistor"), it's the rising cost of building the new fabs and manufacturing chips in them, which means that the cost per gate has pretty much stopped falling beyond 28nm -- and the whole electronics industry is based on "more bang for the buck" with each new process node, not "more bang for more bucks". What happens when the entire planet can only afford one fab?
Economics will kill Moore's law before physics does...
Project Orion used small fission bombs, not fusion. Interestingly the same number of bombs (about 1000) are needed to get any size ship to orbit, and since small bombs (<10kt yield) are less efficient and generate the same amount of radiation as bigger ones, the optimum ship size was around 10 million tons deadweight, propelled into orbit by 10kt bombs going off every couple of seconds.
You can get an awful lot of radiation shielding into that, but anyone watching takeoff might need dark glasses and earplugs even if they were standing on the horizon...
When our kids used to take packed lunches to (junior) school venison sarnies (much cheaper than beef!) were one of their favourites, not just because they were yummy but because when somebody asked them what their lunch was they could answer "Bambi".
Or even better, "Bambi's mum" -- cue squeals of horror from kids who think meat comes in plastic trays from the supermarket...
We've had "terrorists" (and paedophiles, and criminals of all types) in the UK for a long time, and in the old days they could communicate securely using phone calls or letters in envelopes -- unless the police had a warrant to spy on them, for which they needed (at least in theory) to supply a reason.
Why is this any different in the era of electronic communications? The government is claiming that they need to do the equivalent of listening to everyone's phone calls and opening everyone's letters all the time so they can catch terrorists and criminals. Does anyone really think this is OK? How many people are killed in the UK every year by "terrorists" to justify this?
If you're trying to spot imperfections and differences in sounds, this is easier (and much cheaper!) with high-quality headphones (Beyerdynamic, Sennheiser...) than speakers, unless you're fortunate enough to do what high-end studios do and have very expensive monitors in an acoustically-treated room.
Fenton, your point about studios might be correct in ones churning out chart trash, but it's not in the ones I've used. Most critical mixing is done using high-quality monitors (e.g. ATC), the NS10s (or whatever) are used to check that it still sounds OK on lower-fi gear, for example where low bass notes will be inaudible. If you're then doing a demo track to be low-quaility-streamed on the web more compression might then be applied to get the average level up, but this isn't the version that would make it onto an album.
Nigel11, if you're so convinced that MP3s always sound crap and add all these non-harmonic tones, why not put your money where your mouth is and try the test I suggested? (uncompressed vs. 256k VBR MP3)
Proper double-blind tests using high-quality equipment and experienced listeners have been done, and the usual conclusion is that 320kb/s FBR or 256kb/s VBR MP3s can't be reliably distinguished from the originals even with critical material.
I've done the same test myself using high-quality headphones and the studio masters of the band I used to play with -- which do include multiple instruments with a lot of high-frequency content, cymbals, snare etc. -- and came to the same conclusion. So I'm happy to use 256k VBR -- with the LAME encoder, not all encoders are as good!
Anyone who makes claims like "the difference is night and day" without showing that they can reliably tell the difference in a double-blind test -- which they can easily do themselves! -- should be put into the same box as those who promote gold-plated mains cables and green pens for colouring CDs.
And don't get your information about this by reading hi-fi websites, most of them (with a few notable exceptions) are as guilty of promoting the same audio bulls*it as the gullible audiophiles who buy it...
Last time I saw "The Dambusters" the name of Guy Gibson's dog had indeed been overdubbed -- can't remember what to, but it certainly wasn't his real life name...
If you put your foot on the pedal to the left of the accelerator the car will stop no matter what the engine is programmed to do -- no car has enough engine power to overcome the brakes, which is why most of the "unintended acceleration" and "runway car" stories are cases of "wrong pedal syndrome".
Or do you drive a BMW (hence 200+MPH) and only know what the right-hand pedal is for?
I'm in the UK and am perfectly well aware of our energy usage patterns. I didn't say the power couldn't be provided by the grid -- especially at night -- I said that if fuel-cell based cars were considerably less efficient overall than battery powered ones this would be a bad idea, since it would increase our energy consumption on transport, which Prof. Mackay tells us is a big fraction of our total consumption.
A large number of battery cars connected to the grid at night -- and also during the day -- is probably also one of the few energy storage schemes that has any chance of filling in the supply gaps from many renewable sources (no sun, no wind) because it acts as a massive distributed energy buffer.
Obviously there are many other issues with batteries including energy density and recharge time, but the fact remains that is you want to move a vehicle at the minimum energy cost using the power grid to change batteries in cars is the most efficient way to do so, not fuel cells. Given the amount of emphasis that is -- and is going to be -- placed on energy efficiency, this puts fuel cell cars at a big disadvantage.
If you think that fuel cells are going to win over batteries, where is the fuel (hydrogen?) going to come from?
Assuming it's generated by electrolysis, the overall efficiency from grid to wheel is a lot lower than using batteries -- probably around 50% more energy in is consumed for the same energy out. Since the biggest problem with mass adoption of electric cars is providing the power from the grid (not just sourcing it, but distributing it), anything that increases this requirement by 50% is a pretty bad idea.
The only good thing you can say about Beats is that as over-priced under-engineered image-driven products they're still second to Bose...
They're both closed-back...
I've used both in the studio, the DT770 was a lot more comfortable and sounded better all round.
The DT150 is common because it's indestructible and serviceable (and cheaper) but the sound isn't the best -- fine for providing foldback to musicians, but not as good for mixing or listening.
Steelseries Siberia V2 £85
Grado SR60i £68
I know which I'd put money on sounding better...
(OK, Beyerdynamic DT770 Pro is £114...)
Nothing sold as a "gaming headset" is ever going to sound as good as high-quality studio/monitor headphones from Sennheiser, Beyerdynamic, AKG etc., even if it is better than the Beats rubbish.
Anyone buying headphones based on a quoted frequency response with no other information (so how far down is the response at 28kHz, and can you hear this anyway?) is looking at the wrong thing...
To choose cans based on sound quality, look at head-fi.org first. If you want excellent sound and comfort at a reasonable price, try Grado SR60i for open back or Beyerdynamic DT770 Pro for closed back.
When transferring my old vinyl to digital and normalising the peak signal to full scale (after removing scratches and clicks) I almost always find that the end result is quieter than all modern CDs, even of the same album. This is because of the "louder is better" fetish to make CDs "stand out", but the trouble is that once everybody does it nobody stands out any more...
Having sat behind the engineer who mixed and mastered our last couple of CDs, with HDD studios it's now become standard that each instrument has some compression applied to bring up the quiet bits and limit the loudest peaks, and then the final mix has the same. The end result is a higher overall level but with reduced dynamic range -- which is a waste of the much higher SNR of digital compared to vinyl, but that's the way recording is done nowadays :-(
My father-in-law Bill Chandler was the chief engineer who actually built and debugged Colossus -- among other things, he got the first Colossus Mk II working a few days before D-day which led to it happening at all by confirming that the German High Command had fallen for the "Calais invasion" feint.
This meant working through the night on his own on live kilovolt valve circuits; when water started running across the floor towards him he donned his wellies and carried on until he got it working...
Unfortunately he said almost nothing about this before he died, fortunately after writing a paper for the Annals of History of Computing about building Colossus, so I hardly got to talk to him about the whole subject :-(
I know from friends in Germany (and it's now public) that Intel are closing the IGRC R&D centre in Braunschweig which worked on things like the advanced high-speed on-chip networks used for multicore CPUs and was their biggest design centre in Europe. This suggests that they are indeed having to cut back on expensive R&D as their CPU revenues fall, though their choice of which group to can raises some interesting questions about their strategy for the future...
A lot of the complaints coming from the USA don't apply so much in other places like Europe. In my experience the quality of patent filings and examination is a lot higher here -- I've very rarely had a patent application rejected in the USA but the EPO has very often found valid prior art, needing modification of the patent to either explain clearly why this is different, to narrow the claims, or sometimes to just withdraw the application.
We also don't have the same troll/PAE problem as the USA for the reasons stated earlier, software patents as such are not allowed, and the costs of patent lawsuits are not as stupidly high. So don't assume the system is as badly broken worldwide as it is in the USA, because it isn't.
It's still not perfect, patents get granted which shouldn't, and companies use them to stifle a market instead of energising one by leading it. But without patents there's no reward for innovation, you can spend years and millions developing something radical and new and then see it directly copied in a few months by somebody who then undercuts you (because they haven't spent loads doing the development) and takes the market away.
But the criteria of it being novel and non-obvious should be rigorously applied -- especially in the USA -- to prevent stupidities like patenting a rectangle with rounded corners and a screen on one face...
@John172 -- you might also want to look at the price of these Xilinx devices, they've gone this way so they can reduce NRE costs by building a whole familiy of devices out a a few predefined "slice" chips, and get acceptable yield on what would otherwise be enormous almost-zero-yield chips.
Silicon interposers are not cheap yet, especially with the extra processing costs and issues like how to test the die and interposer before assembly, which involves things like bonding/debonding to sacrificial carriers.
In other words, just because McLaren can afford to use a technology in a road car, don't assume Ford can...
The link is *very* directional line-of-sight with a beam width of a few degrees, like a flashlight -- it's intended for a small number of backhaul point-to-point links, not broadcast radio with many potentially interfering transmitters.
Stating that FTTx is optimum in the long run is obvious, until you're in a small village where 1km of road needs digging up to reach a few subscribers. In this case a small dish at each end would be a lot cheaper.
Another possible application is links between the large number of microcell basestations needed for widespread 4G/5G access in cities. Digging up city streets to install the fibre needed to link these -- because many more basestations will be needed than at present to get the network capacity -- is also a lot more expensive than point-to-point radio links between rooftop dishes.
@ Happy Ranter -- smaller batteries with a 20kW motor is exactly what Mercedes have done with the E300 hybrid, which also has a cost premium of only about £3000 over the straight E250 diesel.
This is enough to give hybrid economy and noise benefits (regenerative braking and engine-off coasting, electric only in start/stop traffic, engine start/stop with no delay when pulling away) without a big cost increase or any reduction in luggage space, everything fits under the bonnet.
Whether it delivers the claimed urban economy remains to be seen, but then due to the unrealistic EU test cycle neither do most cars, hybrid or not. What is certain is that with lease costs and fuel costs and BiK taken into account it does make sense for leased company car drivers, which is the biggest UK market for this type of vehicle.
And it's spooky to drive, most of the time while driving the only way to tell that the engine's been switched off is by looking at the rev counter...
For the benefit of non-native English-speakers, there's a traditional dish from the north of England called faggots (they're a type of meatball including liver, traditionally served with mushy peas).
When we had a bunch of friends over from the states, one of our guys who's a serious cook did a sort of "fusion cooking" version of them which were coloured with (I think) beetroot and flavoured with (among other things) lime leaves.
They were very nice, but the main reason was so he could put "Pinko Limey Faggots" on the menu...
One of the guys at work didn't find out that his 5-year-old son had spent just over £8000 in game goodies using his iPad unitl his credit card bill arrived. Luckily he got the entire sum waived, but only due to the goodwill of (I think) the game developer -- 'cos I doubt that Apple would have been so sympathetic, their response at the time was that it was your fault not not disabling in-game purchases...
What Moore actually said was that the number of components which can be integrated *at the minimum cost per component* doubled every two years (or whatever), since this is what drives the economics of what can be integrated.
In this sense it's already dead, even at 20nm the projections are that the cost *per transistor* won't fall below that for 28nm in the foreseeable future, and neither will 14nm, because the cost per square mm is going up as fast as the gates/mm2.
The industry had better get used to the fact that from now on you can integrate more, but it will cost more -- the days of the free luch are over :-(
A large number of electric cars is probably the only energy storage method with enough capacity to fill the gaps when the wind stops blowing to make renewables really work without fossil fuel backup, but there needs to be an awful lot of them plugged in a lot of the time to do this...
Bear in mind that renewables will have a hard enough job replacing fossil fuels to generate existing electricity demand (read "Without the Hot Air"), the added demand from millions of electric cars will make this problem worse.
Apart from the charging problem (which could be helped by swappable battery cassettes) the biggest issue with electric cars is the battery -- cost, weight, range, C02 load to manufacture. It would need a really major breakthrough in affordable battery chemistry (no exotic materials) to fix this, and there isn't one on the horizon yet, a huge improvement in energy density is needed not a small one.
Sounds great in theory, but in practice the power grid eats all the energy that renewables can generate right now, and the balance is made up by fossil fuels. Increasing power grid demand from lots of electric cars today would mean that the increased power required will be generated by fossil fuels, not renewables.
Of course this won't be true in that happy but distant future when renewables (or nuclear fission or fusion) generate all our power, but it is the case today and will be for the foreseeable future.
Tesla's charging stations can only be powered by solar panels on the roof because there are so few Tesla cars using them, multiply the numbers by 100x or 1000x and it's back to juice from those nasty dirty fossil fuels.
It's still true that electric cars have better overall well-to-wheel efficiency than petrol or diesel so the overall CO2 impact is positive, but don't think that all that power comes from nice green sources because it doesn't.
Then there's the battery problem...
But unfortunately, one with considerably lower efficiency than conventional batteries, once all the energy losses are taken into account.
Since the best way to reduce emissions overall is better energy efficiency, fuel cells (or even worse, hydrogen powered IC engines) get a big thumbs-down.
And where does the fuel for the fuel cells come from? And what fuel is it?
If it's hydrogen, the energy to generate this also comes from the same non-renewable generators as for EVs but less efficiently, so the overall well-to-wheel efficiency is far worse and the effective CO2 emissions are worse than a petrol car.
I had to laugh when I was at a conference in Turin last year and heard an American lady trying to order a "lar-tay" at the coffee bar, they'd got no idea what she was asking for -- and asking for it over and over more loudly and slowly each tim ("laarr-tayy") just made it worse.
For those who can't see what's wrong with this, it's a "caffe latte" in Italy, never just a "latte" -- which would be a glass of milk -- and is pronounced with a short "a" because it's Italian :-)
When I was at NPL to do some equipment calibration last year I was amused at a warning sign on one of their optical test benches -- "Warning -- do not look into the laser beam with your remaining eye" :-)