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Comment Ineffective (Score 5, Informative) 351

Technical measures that prevent address spoofing are quickly becoming obsolete anyway; AFAICT, the recent attacks on Krebbs and Dyn, the two biggest DDoS attacks ever, didn't use spoofed source addresses. A spoofed address is only useful in an amplification attack, where you send a small request which provokes a much larger response; then if you don't spoof the source address, you get a huge firehose of responses coming at you and it's you that gets DDoSed, not the target.

In this case, the attackers didn't bother spoofing source addresses, because they didn't use an amplification attack; they just used a huge botnet all making ostensibly-valid requests and each device dealing with the response individually. It looks like the only way we have of preventing this sort of attack is to make the devices secure - easier said than done.

Comment Re:Offshore wind is very uncompetitive (Score 1) 222

The main costs in onshore wind are the grid connection and the cost of steel & fabrication of the tower sections. Between them, over 50% of the cost of the resulting energy. There is progress being made still in lighter, more flexible towers, but I'm not sure how much further there is to go; these days a 1% gain is a big win, while ten years ago a 10% gain was perfectly feasible (eg individual pitch control reduced tower loads by ~ 10-15%). The cost of the grid connection is largely out of the control of the project developer and no-one who is able to reduce it has any incentive to reduce it, so don't look for big savings there. Sure, there's another 40% or so of the costs that can be optimised, but that's spread over lots of small things, so eg halving the O&M costs will not make a big difference to the overall cost of energy. It's hard to see steel getting a lot cheaper than it is, so it seems likely that onshore wind is approaching its long-term cost.

Offshore is another matter. An offshore turbine is just an onshore turbine that's bolted to a support structure that's in the water (more or less) so the costs of the turbine itself are pretty similar to onshore. The main thing holding up the cost of offshore wind is being able to hire a suitable construction ship on a day when the whether is suitable. So yes, development of specialised construction ships that can operate in worse weather, and expansion of the fleet of such ships, is the big factor in bringing that cost down - though it's unlikely to ever match onshore wind. Floating turbines are also a concept that cuts these costs significantly - no need to drive piles into the ocean bed to anchor the support structure - though you do still need some seabed structure for the grid connection etc. I don't think anyone's quite ready to start building large fleets of these (though there are plenty of prototypes around).

Grid connection is a bugger, whether it's for a grid-scale wind farm or a residential solar panel. Way too much of the cost of these systems is just getting the thing connected to the grid. Feed-in-tariffs don't help here, as they make the metering more complicated (you have to measure imported and exported power separately, instead of just measuring net power imports). Someone ought to do something about that. Cheaper inverters and simpler meters FTW.

Comment Some basic flaws here (Score 5, Informative) 298

Off the top of my head:

1. "Every year we hear about people dying in plane crashes. This does not have to continue..." But air travel is already the safest mode of travel. Hear all those people screaming for new technology to make road travel safe? No? Well, they're the same ones that will take this up.

2. "Passengers might board a capsule at a local bus station and wake up in another city on the other side of the country, or planet, after a road, air and rail journey during which they didn't leave their seat." They don't seem to realise the blindingly obvious point that this is making air travel *worse*. Air travel already involves sitting in a seat for too long. Why would I opt for a mode of travel that exchanges a few minutes of having to be polite to people in the aisles for one that involves several hours more in the same damn seat?

3. If you want to see just how off-their-faces unrealistic this is, look no further than this sentence: "Clip-Air's researchers, who are also looking into the possibility of using biofuels or liquid hydrogen as alternative fuels, have already initiated some contacts with the aerospace industry." Oh, great! You're launching publicity for a total redesign of the entire global air freight and passenger industry and you've *already* initiated some contacts with the aerospace industry??? Really??? What made you do that so soon??? And looking into hydrogen as a fuel source for this is basically admitting, "It's so far off the page that we might as well throw in any futuristic-sounding crap we can." If you're doing this seriously, get one thing right at a time. Don't complicate it by also trying to introduce a fuel that no-one else has managed to make work yet.

People who consider themselves "aviation visionaries" (yes, an actual term used in the article) always, always get excited about this kind of thing for no good reason. They *think* people want revolutionary concepts that change how they board planes and let them work out then drink themselves silly in a trendy bar while they're in flight. What people *actually* want are revolutionary new concepts that cut the cost of air travel.

Comment You pay WHAT for mobile data??? (Score 3, Insightful) 145

Bloody hell. Here in the newly-independent UK[1], £11 per month gets me 1GB of data, among other things. Another £3 per month turns that into unlimited data. ANOTHER £2 per month turns that into unlimited data with 4GB of data usable by a device tethered to the phone. That's right, £16 per month for unlimited data on the phone and 4GB for tethered devices. "Heightened competitive environment"? Could still use some work, I think. [1] Yes, yes, I know.

Comment Difficulties (Score 1) 324

Two problems I see with this: 1. Safety. If the grid goes away, this thing will have no reaction torque to apply, and it ain't gunna stop in a hurry. 2. Scale. A quick look at Wikipedia suggests that the heaviest goods trains in use anywhere are about 40,000 t. Suppose you have a mountain where you can raise that 1,000m. The energy involved is roughly 40,000 * 1,000 * 10 * 1,000 = 4e+11 J. That's 4e+11 / 3.6e+9 = 111 MWHr. It's not small cheese, but it's also not national grid scale. As I sit at my desk, demand on the UK national grid is ~31GW. It will last 4e+11 / 3.1e+10 = 12.9 seconds supplying the whole country. That 40,000t train is about four miles long, BTW, so there's a limit to how many of them you can put on the same bit of track. As I say, it's not small cheese, but at the same time, in our renewable-powered future, being able to smooth out a few hours of low wind is going to require a lot of trains and a lot of quite large mountains to drive them up.

Comment Re:Cliches (Score 1) 324

I know you meant this to be funny, but you're probably right. For this to work, of course, it has to use regenerative braking to return energy to the grid. So what happens in a grid-fault scenario, when the regenerative braking can't apply any torque to stop the train?

Comment Re:Web developers (Score 1) 108

If by that you mean javascript bloat, then yes, developers have made a mess of the web. For example, a typical product page on Amazon is 1.8M of *minified* javascript.

The problem is that developers no longer answer to their bosses. They answer to web forums. They are so afraid of doing things other programmers wouldn't find acceptable that they'll code to please web forums rather than doing their job. That means using the heaviest frameworks available and writing the deepest, most complex code they can manage to understand themselves.

Actually the problem is that the idea of doing stuff on a web page, then clicking a submit button and reloading an entire page just for a few pixels to change is a clunky old way of doing things that deserved to die.

Javascript lets us create a richer, more responsive experience that most users prefer. We can provide instant feedback on a field within a form that will fail validation, we can instantly tell people their chosen username is already taken, we can guess ahead at what the might be about to search for and autocomplete for them in a more intelligent way, we can create graphs that track data in real time.

  The possibilities we get from intelligent use of JS open up so many things we simply couldn't do otherwise without native apps. Most users embrace this in one way or another, even if they choose to restrict it to sites they trust.

Comment The Missing Post (Score 5, Informative) 133

He posted a blog post yesterday and it's currently cached but essentially he promises to move BTC from early blocks to do the final verification. This was up yesterday before his stupid wah wah redirect went up. I'm reposting it here in case it's ever removed from google cache (I hate scammers):

Extraordinary Claims Require Extraordinary Proof
May 3, 2016
ExtraordinaryClaims

Yesterday, Andreas Antonopoulos posted a fantastic piece on Reddit.

Andreas said something critically important and it bears repeating: “I think the identity of Satoshi Nakamoto does not matter”.

He’s absolutely right.

It doesn’t – and shouldn’t – matter to the Bitcoin community.

I cannot deny that my interest in bringing the origins of Bitcoin into the light is ultimately and undeniably a selfish one – the only person to whom this should matter is me. In the wake of the articles last December in which I was ‘outed’, I still believed that I could remain silent. I still believed that I could retreat into anonymity, sever contact, go quiet, and that the storm would eventually pass and life would return to normal. I was right and wrong. The story did eventually retreat, but not before it ‘turned’ and the allegations of fraud and hoax (not to mention personal threats and slurs against me and my family) clung to me.

I now know that I can never go back.

So, I must go through to go forward.

Mr. Antonopoulos’ post also notes that if Satoshi wants to prove identity, “they don’t need an “authority” to do so. They can do it in a public, open manner.” This is absolutely true, but not necessarily complete. I can prove access to the early keys and I can and will do so by moving bitcoin, but this should be a necessary, but not sufficient, condition for such an extraordinary claim.

And this is why I wanted to speak with Gavin weeks ago. Gavin was in a unique position as we dealt with each other directly while we nurtured Bitcoin to life in 2010. I knew that Gavin would remember the content of those messages and discussions, and would recall our arguments and early interactions. I wanted to speak with Gavin first, not to appeal to his authority, but because I wanted him to know. I owed him that. It was important to me that we could re-establish our relationship. Simply signing messages or moving bitcoin would never be enough for Gavin.

And it should not be enough for anyone else.

So, over the coming days, I will be posting a series of pieces that will lay the foundations for this extraordinary claim, which will include posting independently-verifiable documents and evidence addressing some of the false allegations that have been levelled, and transferring bitcoin from an early block.

For some there is no burden of proof high enough, no evidence that cannot be dismissed as fabrication or manipulation. This is the nature of belief and swimming against this current would be futile.

You should be sceptical. You should question. I would.

I will present what I believe to be “extraordinary proof” and ask only that it be independently validated.

Ultimately, I can do no more than that.

Comment Re:It's wildly unlikely we should exist (Score 2, Interesting) 267

One flaw? Every single sentence in that quote is either false or unknown. Let's review:
  • It is known that there are an infinite number of worlds, simply because there is an infinite amount of space for them to be in. The universe is not infinite. It may be unbounded (ie have no edges), but that is different.
  • However, not every one of them is inhabited. This one might be true. It is, as far as we know. It might be argued we don't know very much, though. Inhabited with what is not specified.
  • Therefore, there must be a finite number of inhabited worlds. False, as you point out - supposing that the premises are true, the number of inhabited worlds may or may not be infinite.

  • Any finite number divided by infinity is as near to nothing as makes no odds, so the average population of all the planets in the Universe can be said to be zero.The first half is true-ish. Certainly the limit as x->infinity of y/x, for finite y, is zero. What relevance this has to the remainder of the sentence is not clear. If the number of inhabited worlds is finite, then so is their population and each populated world will have a finite, non-zero average population. If the number of inhabited worlds is infinite, then so is the total population.
  • From this it follows that the population of the whole Universe is also zero False, since its premises are false. Even if the premises were true, infinity times an infinitesimal number is not zero.
  • and that any people you may meet from time to time are merely the products of a deranged imagination. This depends rather on your personal situation.

Comment If Only There Was a Website to Answer That! (Score 4, Insightful) 106

This raises one question: Is China's Great Firewall that easy to circumvent, or are members of the government treated differently than normal citizens?

If only we had a website the covered this sort of stuff ... oh right, we do! New VPN IP addresses probably take a while for them to identify the traffic on and block. But there are plenty of services like HMA that constantly roll out new ip addresses. So as long as you're a mouse willing to play whackamole with your cat overlords ... Annoying, yes, but that's the definition of the internet in China.

In response to the second part, that is always true regardless of the answer to the first part. Not only are members of the government are treated differently but also their families. The "party" class enjoys many many perks. Unmonitored VPN connections would be laughable compared to their insider trading, disregard for the law and instant attack dogs they routinely utilize.

While you're accepting suggestions, why isn't my aforementioned article linked in the "You may like to read:" section of this page? Those stories seem to have nothing to do with China's firewall yet a simple google search shows a whole slew of those stories on Slashdot. I think you could get timothy's family to help you track that stuff if you would return his body to them. They only want closure, it doesn't matter if it has to be a closed casket funeral!

Comment Re:AC is by its very nature inefficient (Score 3, Insightful) 245

If you don't understand why this isn't going to happen, you need to be kept away from grid design.

Replacing the AC network with a DC network would mean either replacing or substantially modifying the entire fleet of existing generation plant, all distribution and conversion equipment, all industrial equipment powered by electricity and most appliances. You might well be right that you can achieve better efficiency in a new network with DC than with AC; when you have to replace the entire electricity system, from spinning turbine to phone charger, it just ain't gunna happen.

Comment Re:Efficiency (Score 3, Interesting) 245

Maybe, though Hack-a-Day say it involves an "incredible thermal management solution," which doesn't sound like they've actually bumped the energy efficiency up that much.

Why were Google so keen to have an inverter that maximises power density? Why not maximise energy efficiency?

Ideally you'd like to minimise cost of energy. But I guess it's fairly difficult to construct a competition around this: It depends too much on production scale and the prevailing cost of electricity. But why power density as a substitute?

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