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Comment Re:"capability to cut cables" (Score 1) 273

Unfortunately, even at great depth, underwater explosions in contact with any surface can easily be intense enough to induce substantial cavitation. The long duration impulse from the explosion is converted to a very short duration impulse on collapse. This impulse is sufficient to cut though plate steel at appropriate depths (at depths where the close proximity pressure wave intensity is greater than ambient pressure) . The confinement of the explosion impulse to a small area at greater depth allows a relatively efficient conversion to the impingement energy. The time available to lose energy thermally is greatly reduced. The impulse intensity and duration in these kinds of operations is more than sufficient to blow apart an optical cable about the size of your thumb... by a wide margin.

Other than that, being in close proximity to a cable of that size, it is far easier to simply cut them.

Comment This is old news, not a new threat. (Score 1) 273

The Russians, Americans, French, British, Germans, and others all have active programs to disrupt undersea communications, and they have had them for a long, long time.

This is not rocket science. A group of undergrad and graduate engineering students has demonstrated the use of low-end side scanning sonar and Rube Goldberg AUV tech to detect and track underwater cables for up to 2 weeks and 350 miles autonomously. The cables themselves are scarcely bigger than your thumb in deep water, and quite fragile (easily cut or percussively disrupted). The current they carry (yes, the optical ones too) are detectable from dozens of meters with inexpensive sensors as well.

The undersea infrastructure has always been prone to periodic failure, let alone vulnerable to deliberate attack. There is little a determined naval forces can do to prevent these possibilities aside from attempt to provide redundancy, which is not a military function, or deterrence, which is arguably a function that can be effected with political or non-naval resources better than naval resources.

The bottom line: nothing new here, no greater vulnerability exists now than before the Navy was fighting the backchannel war to feed the mouthbreathers to get more funding.

Comment Journals are prestige merchants... (Score 3, Interesting) 204

Journals were once curators of information relevant to a subject for areas of interest outside the reach of traditional library curation.

Library science has been quietly and revolutionarily been relegated to obsolescence in the age of the internet.

Journals would be functionally relegated to the same fate were it not for an additional value they add to academia...the constant search for prestige and citation that academia demands.

A Nature pub simply offers more social intangibles than Arxiv.

More societal benefit might be derived from other open access alternatives, but those alternatives offer no career and personal intangible benefits in the way that Nature offers.

Comment Winds... (Score 2) 61

The winds at the float altitude of 120k' (36km) have frequent and sustained gusts exceeding 25 m/s. The air is thin, and barely perceptible, but the effects of vortex shedding around structures is still vexing for those of us who try to keep payloads pointed and vibrations minimized. The PSD of the vibrations is sometimes significant in the lower frequencies. The PSD of the vibration profile shifts, sometimes dramatically, in real time to the measured winds and directional changes of the payload gondola at those altitudes.

As for a microphone freezing over, the environment at those altitudes will very quickly shed any moisture accumulated in any phase on exterior surfaces. A balloon typically rotates throughout its mission, and the extreme cycling between view factors for albedo, direct solar radiation, and deep space cycle any moisture accumulated in the tropopause or below in minutes unless the surfaces are somehow unusually shielded.

Comment this machine can be used to make a pipe bomb. (Score 1) 449

Or a chew toy. Or a switchblade. Or a baby pacifier.

Who cares?

The only thing that keeps us safe from bad people is a lack of bad people that want to do us harm. Anyone anywhere can make or procure the necessary materials to kill, maim, or otherwise harm someone else or commit mass murder. Legislating common tools like a mill or a hammer is an affirmation by a sponsoring legislator that they might not be particularly intelligent and that only the most reactionary fear based rhetoric can move legislation in modern America.

As.for this scheister...he is no revolutionary hand model. He might as well be screeching, "F=ma....F=ma!!!". The only reason he is getting attention in the first place is because he is obsessively calling attention to simple truths that cross people's preconceived notions about security, government sanctions, rights, etc.

I'm always surprised how basic discussions of these things become embroiled in frothy emotional Turret's outbursts on every side of an issue.

Comment Why is this interesting? (Score 4, Insightful) 449

I have large CNC machine shop. Anyone else I know with a CNC machine shop in their garage of any size has probably made guns. Some of them have made full auto versions. Some have made mortar launchers and artillery cannons and other stuff. This has been going on for many decades...and yet it is barely even visible. No end of the world. No crime wave. The difference here is volume, not principle.

Guns are not even interesting after growing up with them. I don't understand why people are so obsessed with them...but then again, I don't know why Pharrell's "Blurred Lines" was even a blip on the music scene. But I have to admit the fetishization of firearms gives me the is a disturbingly reliable indicator of a state of mind I am wary of, avoid, and consider pitiable.

Nonetheless, I feel compelled to defend the right to make and use firearms because once I declare the 2nd amendment is worthless, their state of mind could easily compel them to decide that any of the freedoms I enjoy are equally worthless. Heck- a majority of Americans already do. I tend to place the majority of persons around where I live who openly carry in the same category as some of the unfortunate homeless ranks who suffer to spew collections of epithets at passersby. It is generally harmless, certainly within their rights, although somewhat disturbing. To feel they are that much under threat by the world around them is a lousy way to get through a day. To outlaw that sort of thing would also be a crime.

Build guns. I don't care.It is the least of any imagined problems that Americans have, and to ban the information or even their manufacture literally on a par with banning books or ideas in my mind.

Comment The same can be said for helicopters.... (Score 1) 280

The widespread use of helicopters in law enforcement is largely a waste of money as well. Nearly all LE helicopters are flown, by policy, at altitudes and speeds appropriate for fixed wing assets that cost 1/8th as much to purchase and operate.

It's a boondoggle. When the budgets come down, it is always the "don't take away our chopper, man. They are so cool and intimidating to crooks" arguments. They seldom provide *any* additional utility in practice (planes orbit a scene at the same speeds and altitudes).

If you were to load the incidents that use a helicopter's specific abilities in those rare incidents that require them, the costs are astronomical. In LA, only 4 incidents from an entire fleet that costs several 10's of millions of dollars were recorded in 2013.

It makes drones look like a deal by comparison. Or not...

Comment Default warrantless wiretaps create lawless zones. (Score 1) 431

Destroying the 4th Amendment of the Constitution without comment means ubiquitous encryption is perfectly fine with me.

I've got nothing to hide. Why do you want to look?

The trend towards surveillance is a diversion. The security apparatus is less effective, less capable, and less talented than it has been in the past in identifying real threats vs inventing paranoid scandals. It seeks greater immunity and secrecy from accountability simply because, for all the investment in its promise, it fails to deliver. Every time.

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