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Comment Re:The big question (Score 4, Informative) 100

We sometimes forget just how heavy water is, or how much energy ocean waves carry.

Some time ago, I did some statistical analysis of wave heights in Scapa Flow, not far away from the site proposed here in northern Scottish waters. It has very steady, large swells.

Imagine a wave (or swell) of 10m peak height, extending 2 km across, and 50m front-to-back. That's a nice 0.3 * 10^6 kg of water ... move it forward at 30kph ... repeat every 10 or 20 seconds, and you've got 10^9 Joules/second, about 1GW. For the surface wave. (More energy is transferred more steadily by sub-surface currents.)

Lunar tidal flows are so much larger than these that the prospect of drawing enough energy from open waters to do anything to earth - moon movements seem to be off by many orders of magnitude.

Full disclosure: I used to be a pretty good physicist, but that was a long time ago.

Comment It's fun to blame AT&T but ... (Score 1) 441

Perhaps phone companies really ARE evil, don't know.
But here's the way some of this works as a business:
1. Spectrum auctions (and landlords charging for antenna locations) are economically perfect mechanisms to drive the business case for wireless services to nearly non-existence. Spectrum auctions almost necessarily push telcos to pay nosebleed prices, just to participate. (The UK auctions were manically unhinged: they had a rider saying that BT would lose its GSM license unless it bought 3G spectrum. In consequence BT just about *had* to pay whatever it took, just to stay in business.) Auctions are not about valuing assets, they're a hidden tax. The cost of equipment is not nearly as critical a cost factor as the cost of cell sites (~100,000 per major carrier in the US) and the spectrum; both lack competitive supply/demand forces to contain them.
Likewise, landlords are armed with economic models and consultants that drive every last red cent out of business models too. Hey, that's how business works.
The cost of equipment is not nearly as critical a cost factor as the cost of cell sites (~100,000 per major carrier in the US) and the spectrum; both lack competitive supply/demand forces to contain them. Operating networks with tens of thousands of nodes in the USA's large landmass ain't cheap.

2. Along come smartphones and these and and apps, (and misleading marketing) create soaring basic demand;

3. Bloated apps (Skype, ugh), IP and (e.g.) the Van Jacobsen quickstart algorithm then take said traffic and inherently drive it to network saturation.

So: perhaps telco execs are satanic, let's get pitchforks and blazing torches.

But, the economics and technical dynamics of the marketplace are in inherent conflict. US gov't policies are at least as much to blame. And so are landlords.

The analysis can get much deeper - but without revealing a useful solution for the US, alas.

Comment Quality of data ... (Score 2, Interesting) 232

Some of the old data can be of great quality - so these exercises can be highly useful.

A couple of decades ago, I worked - as a student intern - at British institution. A question came in on wave heights in the North Sea ... a firm was wondering about engineering tolerances for oil rigs and such. I had to go to the data: much from the last few decades was already computerized and I did a quite stats analysis - and was surprised at how many BIG waves were observed. This would be very costly to the rig builders ... so I was told to go and re-sift the recent data and dig up older data. The recent data sift yielded the same output. The old data ... going back to the 1700s ... showed the same statistical patterns (so long as you squinted at it a bit - the responsible sailors either were not at sea and certainly were not taking measurements in big storms, or didn't get to survive). The outcome was - as I recall - that in this particular spot of the North Sea, you'd see a wave (or cluster of waves) over 40' high every two or so months.

The reason for the tight correlation, of course, is that the data was being taken the same way: sextants and the like, with data literally tabulated by hand: and - registered vessels had someone on board whose job it was to take and log the data - it wasn't something done ad hoc. The systemic errors were consistent for two-plus centuries. Data since the 1980s is automated and since the 1990s is from satellite maps.

Comment Network-based spam blockers (Score 1) 157

... like network-based virus blockers bring several good things:
* an entirely different set of algorithms can be used, leveraging data and traffic patterns not specific to the message contents
* a team of engineers not tied to a single enterprise

And, indeed, major network operators like to do stuff like this - takes traffic off the network, and relieves enterprises of evil traffic forms (including DDOS)

BUT then, net neutrality purists, like 4chan, despise this and fight back, as recently when AT&T worked to thwart a large-scale DDOS attack.

Comment P2P = security hole (Score 1) 307

About 5 years ago, I led a private project that looked at the terms most often searched over Limewire, Napster, etc. The results were most similar to those of an academic study that emerged a bit later: the most commonly-searched terms were NOT popular songs or p0rn. They were pings for bank account information, SSNs and passwords.

Comment Re:What about Microwave Ovens? (Score 1) 515

Of course this is utter BS. But lest we forget: the Wifi AP will be on 7/24, while the typical consumer micro will only be in use 30 mins per day, perhaps 5 days/week.
Note: I'm not defending the nutty guy who alleges he's allergic to 2.4GHz from wifi, just saying the counterarguments should be watertight, and comparisons to consumer micros aren't inherently watertight. (And yes that is a pun, for those of you paying attention to why 2.4GHz works.)

Comment Edison's claim (Score 1) 539

Few tropes are as tired and tiresome as Edison's claims, such as 'I haven't failed; I've found 10,000 ways that don't work.'

Back then, Edison could (and did) hire hundreds of engineers, have them grind through the experiments, and then claim their inventions as his own. It was then legal for a single powerful executive to claim all patents as his own, even when he'd done none of the work. (Now, they just get to claim they're co-inventors.)

Comment Re:what kind of freedoms? (Score 1) 1359

Switzerland is an extraordinary example of the challenges.
Its economy, to a larger degree than any other country, depends on money laundering. So, the freedoms of the Swiss are propped up by the suffering of the populaces of countries whose dictators or corrupt magnates need to stash their ill-gotten gains somewhere safe. (Nazi theft of Jewish wealth all went to Swiss banks, for example.)

Comment Re:NYT quote is a bit unfair ... (Score 1) 203

But the logic you use seems to imply a long life for the asset. In fact, Internet gear gets used up so quickly (as bandwidth demand rises) that in fact it typically has a life-in-place of two or three years. So, while it's charming to assert that the variable costs are low, it's also irrelevant.

Put it another way. To build an infrastructure that serves several million households and businesses will cost several billions of dollars. To make that network still useful in, say, three years' time, the operator has to again spend billions of dollars.

So the most useful way to compute the effective variable cost is NOT to assert "it's low" but to actually divide the entire cost by the traffic throughput (current peak offered load). A few years' back, doing the calculation this way suggests a variable cost for transmitting a DVD-quality movie to be about $2, and for transmitting an MP3 song about $0.05. I am sure these estimates are off now, perhaps by a factor of 10. But not by a factor of 100.

Also: the Comcast figures are obviously nonsense. If the variable cost to CMCSA was so low, they'd have deployed it everywhere. In fact, the figure the Comcast guy cites is the cost to upgrade the shared headend. Unfortunately, they also have to upgrade the taps ($100 plus labor) and the in-home terminal ($100 plus labor). Often, also the coax into the home needs to be replaced. And the hub near the home.

Comment Google's monopoly (Score 3, Insightful) 107

While Google is protesting Microsoft's de facto monopoly of desktop client software, it is working hard to create a de jure and de facto monopoly for itself in an important area of content. In the proposed settlement, Google is the ONLY legal site for ALL [in copyright but out of print] printed content.

How is this a good thing?

Apologies for the cowardly anonymity, not my normal style, but there's plenty to worry about here.

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