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Comment Audio detection (Score 2) 227 227

Audio detection does NOT work

I'd be inclined to modify that statement, and say. "Audio detection does NOT work, now".

Each rotor of a quadcopter is going to emit sound that depends on the number of prop blades and the prop speed. The four rotors will emit at frequencies that are almost but not quite the same, The four frequencies continuously shift by minute amounts as the control system adjusts power to stay stable in the air.

The quadcopter therefore has a very distinctive sound signature. This signature is out there, waiting to be detected, if the money can be found to develop the technology to do it.

Presumably if that happened, there would be a push for stealth quadcopters. But that's another kettle of fish.

Comment Real porpose of the road (Score 3, Informative) 226 226

The Russian's don't give a damn about connecting London to North America.

What would be of more importance to them is better transport infrastructure between European Russia and the Russian Far East. Across much of thet route, roads are simply non-existant even today. If you drive from Moscow to Vladivostok then you're not taking a journey, you're mounting an expedition

Why would they want this infrastructure? Well large numbers of Chinese are moving north to settle in Russia. There's speculation that Chinese will be a majority in the Russian Far East few decades. See:

Better commincations across Russia will help them counter this and help tie the country together.

Comment This is very Interesting (Score 1) 187 187

It was always an assumption that when the automation became good enough and cheap enough compete with low-paid Chinese workers, then manufacturing would come back, it would be onshored, After all, removing labour costs removes China's compelling cost advantage. Doesn't it?

Now this announcement is an indication that this may not happen. China has built up such a massive web of suppliers, often in close proximity, that it now has a compelling logistic advantage. Even if you wanted to build a completely automated laptop factory, with only a handful of maintenance workers and labour costs so low they're lost in the noise, then putting it in China might make more sense than putting it in Europe or the US.

Comment Submarines Move (Score 2) 75 75

Nuclear submarines move. So if the experiment is run for long enough, then the skew caused by having one pass by in the nearest stretch of ocean won't be a worry.

Saying that, I imagine various navies and intelligence agencies will be paying a great deal of attention to this research, if they're not already doing so.

Comment Re:nitpicking nomenclature (Score 4, Informative) 66 66

They contain gasses in the envelope that is lighter than air but not enough to provide sufficient buoyancy for lifting the entire weight of the craft. They'd technically be still heavier than air and would require the engines running to leave the ground. I don't know if the Goodyear airships are lighter or heavier than air.

You're right, I believe Zeppelin NTs are several hundred kilos heavy on take-off, when carrying payload and full load of fuel. Though they can be lighter than air when landing with the fuel mostly gone. Of course the other big complication to trimming a dirigible is air conditions, which can change during the flight. Buoyancy increases significantly if an airship flies from warm air into a bank of colder, denser air and the craft will remain buoyant until the helium cools to match the air temperature. In the old days, air

All this is what makes vectored thrust a fantastically useful thing for an airship pilot. It gives better control and also means the pilot can vector thrust up to land when his/her craft is lighter-than-air. I'd say this is vital for keeping costs down, as it avoids venting helium for landing.

Although the usefulness of vectored thrust was no lost on the early designers. See this picture of a pre-World War 1 British military blimp with rotatable props.

Comment Re:As an organiser of events. (Score 1) 469 469

I'd love facial recognition. I have a really bad memory for names and faces, and I often end up in the embarrassing situation of meeting someone in the street who knows who I am but I only vaguely recognise their face and certainly don't remember their name. Having a prosthetic "face to name" system would save me from many embarrassing situations.

No, I'm fairly certain you have a memory for names/faces not much better or worse than anybody else.

It's just that people who appear to be better at it than you are simply more aware if its importance and, have gone to the trouble of employing various memory aids and tricks to help them do it effectively.

I'm speaking as a snowboard instructor, who must memorise the names of a class of 12 more-or-less instantly on introduction to them at the start of the first lesson. Because teaching a class without being able to address individuals by name is noticeably harder.

Comment Re:First (Score 1) 250 250

Interesting addendium to the interesting addendoim....the Daily Expresses' actual Muirhead picture receiver, that got plugged into the big dish at Jodrell Bank, still survives and is preserved in the Museum of Science and Industry in Manchester.

Check here if you want to hear what the signal from a Muirhead sounds like, and presumably what the people at Jodrell actually heard coming from the moon.

In case of injury notify your superior immediately. He'll kiss it and make it better.