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Comment: Re:Misplaced location (Score 1) 130

by Ungrounded Lightning (#48591387) Attached to: No More Foamy Beer, Thanks To Magnets

This is needed at the bar when pouring into a glass or pitcher.

By then it's far too late. This is about spreading out the active ingredient from the hops during the original mixinig, before brewing, so it can keep the ingredient from the fungi from loading up on carbon dioxide during brewing. By the time you pour, the opportunity for the hops to do anything but add flavor is long gone.

Comment: All valid except one point: (Score 1) 225

by Ungrounded Lightning (#48571163) Attached to: US Navy Authorizes Use of Laser In Combat

Nearly all of what you say are valid points. But one carries a misconception:

By it's very nature of being a focused, collimated beam a laser does not affect anything in "the general direction" of the target - if it was not focused and accurate, it wouldn't be an effective weapon and might not even be dangerous.

That's SO not true. There are two issues here:
  - Forward (and back) scatter: A laser beam "leaks" light, primarily in the "general direction" of the main beam and, to a lesser extent, in the general direction of back toward the source. It's not a big percentage. But when you start out with kilowatts of colimated light it can be more than adequate to burn out a human eye.
  - Scattering (also specular reflection) from the target, or the cloud of gas that remains of the target. This can be a substantial fraction of the incident beam.

"Do not look at the beam or the target with the remains of your face."

Comment: I don't see the problem (Score 4, Interesting) 135

by Ungrounded Lightning (#48571117) Attached to: Rosetta Results: Comets "Did Not Bring Water To Earth"

Deuterium/Hydrogen (D/H) isotope ratio is significantly higher (more than three times, in fact) than that of water found on Earth.

Q: How do you separate heavy water from light water?
A: Distillation. Light water boils off / evaporates more easily, because the molecules are lighter, and leaves the heavier water behind.

Why shouldn't this be true of vacuum sublimation as well?

Leave a chunk of dirty ice orbiting the sun in a hard vaccuum for a few million years, with the water quietly sublimating away. Seems to me the result would be that last remaining chunk of dirty ice would have a substantially larger fraction of heavy water molecules than the water on the planet where the deep gravity well hangs on to the lighter molecules.

Is it enough to explain a 3:1 enrichment? No clue. But I'd like to see that the analysis was done and what the scientists' estimates were.

(Not to say they ignored it. The last time I raised a similar question about a scientific paper reported here it turned out that the scientists HAD examined the issue.)

Comment: Violation of the "Takings" clause. (Score 1) 178

by Ungrounded Lightning (#48569909) Attached to: LA Mayor Proposes Earthquake Retrofits On Thousands of Buildings

This will cost us billions of dollars in the private and public sector,

who is this "us" he is talking about?

The taxpayers. It's a clear violation of the "takings" clause of the US Fifth Amendment (long since incorporated against the states and their subdivisions, including the City and County of Los Angeles.) This means, after a bunch of legal wrangling, the courts are very likely to rule that applying such a law against a pre-existing building is a "partial taking" and the government must make the owner whole, i.e. reimburse him for his costs of compliance.

The takings clause:

No person shall ... be deprived of ... property, without due process of law; nor shall private property be taken for public use, without just compensation.

if the public good is really being served here by improving safety of citizens, why isn't the discussion framed more along these lines?

When it gets to the courts, it will be. Count on it.

Comment: This might alienate anti-ISI* Muslims. (Score 2, Interesting) 225

by Ungrounded Lightning (#48568243) Attached to: US Navy Authorizes Use of Laser In Combat

One of the religious prohibitions in Islam is making war with fire.

If this is used it will be interesting to see the effects on recruiting by the Islamic State and other anti-US organizations among those Muslims who are currently either opposed to them or unaligned.

Also: How do you keep a 30 kW laser, at any frequency, from blinding everybody in the general direction of the target? The last I heard, weapons that blind are banned by the current "laws of war" as recognized by the western powers - and that's been the major impeidment so far to deploying laser (and other directed energy) weapons. Has something changed? Or did the current administration just decide to play with the new toy despite past promises to the other kids?

Comment: Re:How ? It doesn't have 3G / WiFi. Needs a router (Score 4, Informative) 46

by Ungrounded Lightning (#48553323) Attached to: Bluetooth Gains Direct Internet Access, Security Enhancements

How is this "directly connected to the internet" when it is using a router to access the net.

By that definition, NOTHING connects directly to the internet.

Anyone with a better understanding care to explain ?

The proper definition of a host running an internet-facing application being "directly connecting to the internet" is using IP for the first hop, with the packets having a route from there to and from the rest of the Connected (capital-I) Internet.

Bluetooth 4.2 added support for IPv6 to/from bluetooth devices. This means IP packets formed on, or directed to, the Bluetooth 4.2 hosts, for delivery to/from other Internet-connected devices, do not require a protocol-translation gateway to select and translate some subset of the packet types, services, and features, modifying the transport semantics to support some tiny subset of functionality that the gateway explicitly understands. An IP packet formed on the bluetooth device goes all the way to its destination semantically unmodified, and ditto packets going from some other device to the bluetooth device. The full feature set of IP (or as much of it as the stack implementer choses to support) is available, while the routers can be "as dumb as rocks" and totally ignorant of what the application on the Bluetooth device is up to, in classic Internet style.

A Bluetooth 4.2 device, using IPv6 and with a route, IS on the Internet, and is a peer to all other internet-connected hosts.

Comment: Some of us (Score 2) 118

This is relevant to nerds and technology how?

Some of us are eco-nerds.

Seriously. Planets and space habitats will need ecological engineering - the real stuff, not the eco-wacko knee-jerks.

Examinations of how this horrendously complex system works when tweaked are definitely "news for nerds" and "stuff that matters".

There are lots of different sorts of nerds, and lots of nerds geek out on many different technologies each. If you sometimes see nerd-fodder that isn't on one of YOUR subjects on Slashdot, suck it up and shut up, while the nerds of THAT topic finally get to have THEIR conversation.

We get enough of that disruptive raining-on-our-parade from the jocks.

Comment: And other police misconduct. (Score 1) 218

by Ungrounded Lightning (#48528349) Attached to: 'Moneyball' Approach Reduces Crime In New York City

That the list contains people without convictions means that you can be added, and your sentence affected, by things you haven't been proven guilty of: Due Process Fail.

That stuck out like a big sore thumb to me. It's police and prosecutorial misconduct, pure and simple. (I'm appalled that this wasn't brought up until this far down in the discussion.)

Other items, just from the little bit quoted here:
  - 'people whom the D.A. considers "uncooperative witnesses,"'

One of the big differences between the US and English systems is that in the US you are NOT REQUIRED to risk your own life to do the police department's work by testifying about what you've seen. (You aren't allowed to lie, but you are allowed to be silent.) The police often can't, or won't, provide you with protection against criminal retaliation for your testimony, at the same time that they block you from obtaining or using the means to protect yourself. Don't want to be a martyr? Just say nothing.

But these guys are turning that principle on its head: If they decide you're an "uncooperative witness", into the database you go, to be harassed and minutely scrutinized from then on, threatened with arrest at any slip-up, treated differently, and far worse, than other citizens. That's selective enforcement at its worst, and denial of civil rights under cover of law.

Then there's "gang members". If some policeman don't happen to like you and the friends you hang out with, they he can define your group as a "gang", regardless of whether you've committed any crime, and treat you and your group as they would big-time repeat offenders. Any bets on whether this gets used against political opponents of the prosecutors' party?

Comment: Barrage balloons. (Score 1) 116

by Ungrounded Lightning (#48477733) Attached to: Ask Slashdot: Best Drone For $100-$150?

Try flying some small helium party-style balloons on kevlar fishing line tethers, creating a forest of near-invisible strings.

Copter drones don't fly well with the blades wrapped in string.

(Indeed, I hear full-sized helicopers don't work all that well with a few hundred turns of 75-pound test line wrapped around that pitch control mechanism at the hub, either.)

This might not work against those with the bumpers all around. But the ones with the blades unguarded would have quite a time getting through.

Comment: Land not suitable (Score 1) 47

by Ungrounded Lightning (#48477703) Attached to: Interviews: The Hampton Creek Team Answers Your Questions

Livestock require 8-20x more land per gram of protein produced than plant based protein sources. Switching entirely to plant based foods would allow returning >90% of that land to its natural state and growing crops only on the most suitable 10%.

Much of the land of the continental US is unsuitable for growing any crop suitable for human consumption, due to things like lack of water. The western range, for instance: Attempting to farm it would be an ecological disaster. Cattle, on the other hand, can make a fine living off it (at a rather low density - like four acres per cow) and ARE suitable for human consumption (and tasty!) when raised on what they chose to eat.

In fact, NOT raising range cattle on range land is ALSO an ecological disaster. US range land has a substantial infestation of invasive grass species that were accidentally introduced by European settlement. The native animals tend to avoid eating it, so it has an extra selective advantage over the native grasses and tends to squeeze them out. Cattle, on the other hand, prefer it - to the point of eating it almost exclusively when it's available. Thus they keep it under control. Meanwhile, any non-cattle attempt to eradicate it would amount to total defoliation, reseeding with native plants, crossing your fingers that the invasive species was wiped out, and repeating whenever it reappears.

Comment: Also, chickens can't be free range and organic (Score 1) 47

by Ungrounded Lightning (#48477667) Attached to: Interviews: The Hampton Creek Team Answers Your Questions

Wait, is organic and free range supposed to be a better, that is tastier, product or just better for the environment?

While we're at it: If a chicken is free range it isn't organic. A free-range chicken eats wild bugs, and you can't certify that all the wild bugs that flew in ate an organic diet themselves.

My wife raises chickens, studies the issues extensively, and has a lot to say about free range, organic feed, organic chicken regimes, etc. They amount to animal cruelty. Some of the high points:
  - Free range means the chickens are exposed to predators and avian diseases spread by smaller birds.
  - Organic regimes forbid antibiotics and often vaccinations. A bird that catches some disease will either be dispatched to save the rest of the flock, or left to suffer and recover on its own without assistance - perhaps crippled - and meanwhile expose the rest of the flock. A number of poultry diseases are endemic among wild birds or prevalent in the enviornment. Young chicks are subject to coccidiosis and many of the survivors then live with damaged digestive systems. (Non-organic chicks are usually fed a coccidiostat in their early-weeks feed until their immune systems develop, or given a dose of antibiotic if the disease appears in the flock.) Marek's Disease, caused by a herpes family virus, is common. It produces partial paralysis, blindness, lymphoma, immune suppression, tumors, atherosclerosis, and a range of other painful and debilitating symptoms. Non-organc chicks are vaccinated against it. And so on.
  - Free range means the chickens are in large groups rather than individual cages with a handful of birds in each. Chickens can keep track of the ranking of no more than about a hundred other individuals, so life in a larger group is a constant series of battles to reestablish dominance. In small group cages, on the other hand, the heirarchy is worked out quickly and peace generally prevails (or relative peace, depending on breed). This is partiularly a problem with commercial egg-laying breeds, which are noted for intra-species violence and cannabalism.
  - Free range chickens are allowed to leave the barn in the day. But only the few who set up their teritory near the door actually get to leave. The rest are still effectively confined to the buildng in a mass of interacting birds.
  - Commercial feeds from big-name animal feed suppliers are tightly quality controlled and well tuned to the birds nutritional neefd an their taste preferences (so they'll enjoy eating it and thus eat as much as they should). Organic feeds are noted for dangerously poor nutritional qualities, from bad formulation choices, variation between batches, and the use of ingredients that quickly lose their nutritional qualities during storage. With their high metabolism, an under- or mal-nourished chicken will becomes a damaged and debilitated chicken in just a few days.v

I could go on...

Comment: -457 farenheit is nothing to sneeze at. (Score 4, Insightful) 145

by Ungrounded Lightning (#48477215) Attached to: Scientists Develop "Paint" To Help Cool the Planet

What the material is doing (or is claimed to do, anyway) is to re-radiate incident radiation at a wavelength that can pass through through the atmosphere back out to space without being absorbed (i.e. it won't heat up the atmosphere).

More importantly: If the wavelength were one that was absorbed by the atmosphere, it is also one where the atmosphere radiates heat back toward the paint.

If your frequency slot is one with "absorption", you "see" the temperature of the atmosphere - a bit cooler than the surface of the (greenhouse-effect boosted) planet, but not by enough to be exciting.

If your slot is one that is essentially fully transparent, you "see" the cosmic background (except for the tiny part of the sky that shows the sun's or moon's disk). That's about 2.7 degrees K, call it -457 Fahrenheit. Liquid helium is substantially warmer at -452.2.

The slow radiation of heat at the sky is almost completely overwhelmed by conductive and other transfers of heat into the paint, of course. Of the 530ish degrees F difference from room temperature, only nine are left.

But that's nothing to sneeze at. The inside of my well-insulated desert house gets up to about 85 in the day without air conditioning. If I could drop that by nine degrees it would be a relatively comfortable 76. (It would likely actually drop more, because the lower temperature of the surface would slow the heating and tend to even the daily cycle of temperature out further.) 85 or more is debilitating. 76, with drastically low humidity (dew point typically about 35), is actually comfy.

Comment: Not zero cost. (digression on my sig line) (Score 1) 29

by Ungrounded Lightning (#48465363) Attached to: NASA To Deploy Four Spacecraft To Study Magnetic Reconnection

Make a basic income available to everyone (funded by the Fed, not the taxpayer, at zero cost).

The point is that it's not zero cost. Every penny of money "funded by the Fed" comes from your and my pockets - sometimes with a big multiplier - by paths that are not as obvious, but just as costly, as a tax bill.

The biggest one is inflation: If the Fed just prints money, it dilutes the rest of the money. Your wages go down (though the numbers don't change.) Got retirement savings? They go down, too. Your investments go down - but the numbers make it look like they wen't up, and the government taxes the fake "gain". Everything you buy gets more expensive.

Comment: Fusion power applications? (Score 1) 29

by Ungrounded Lightning (#48462139) Attached to: NASA To Deploy Four Spacecraft To Study Magnetic Reconnection

It will be interesting to see whether this research on the phenomenon in the large scale produces insights useful at the smaller scale of fusion plasma confinement.

In case it's not clear, magnetic reconnection is a phenomenon of magnetic field/plasma interaction. (Without the plasma and its currents (or extreme accelerations like those around black holes) the magnetic field wouldn't be simultaneously twisted up and bent around so it can reconnect differently.

I see two ways this might apply to plasma confinement in fusion systems:
  * It may give insight into the details of plasma instabilities and lead to ways to suppress them - enough for a practical reactor.
  * It might lead to a way to use the phenomenon deliberately, to produce a (probably pulsed) past-breakeven plasma confinement, along the lines of Dense Plasma Focus.

Comment: More than half were minority owned, too. (Score 1) 1128

by Ungrounded Lightning (#48461993) Attached to: Officer Not Charged In Michael Brown Shooting

The hit is taken by the store owners and their landlords. [Insurance usually has escape clauses for riots.]

Just heard on the news that more than half of the stores destroyed last night in Fergusun were minority owned, too. (I think it was actually "black owned" but I'm not sure.)

IMHO the main point of the burning is so that, once the stores have been looted, the evidence of who did it is largely destroyed. Video survelience tapes, fingerprints, serial number records, ...

Always draw your curves, then plot your reading.