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Comment Re:The bug isn't all that bad (Score 1) 298

Considering it requires malware to be run on the system, there are better ways to spy out user's passwords (without dumping some 32GB of RAM). So, why bother?

The attacker's malware doesn't have to dump all the physical RAM. It CAN do so, if he feels like it. But it can also read it selectively, RAM style, a bit or byte at a time. So he can just go right to whatever he wants to see.

Given that the side-channel bandwidth is about that of fiber-to-the-curb DSL, rather than a memory bus, that is actually the preferred way for such malware to operate.

Comment Re:Same speed in same lane good, different lane ba (Score 1) 404

Dunno what you teach your drivers over there, but there's generally regarded to be one lane, and multiple "overtaking lanes" in all the terminology for most of the countries I have seen driving-school things for.

  When you have two lanes in the same direction, that terminology, and acting on it, makes sense. When you have, for instance, six lanes in the same direction, it does not. The extra lanes are about increasing capacity, and are intended to be used for long-distance driving rather than just passing slower traffic.

That's the sort of highways we have over here. (Especially in high-population states like California, for instance - I commute on such a 12-lane stretch every day.)

The laws have been adjusted according to this purpose. For instance: Passing on the right is expressly legal in California. On the other hand, excessive lane changes (as you'd have to make to use the "passing" paradigm) are added hazards when the lanes are being used for travel rather than merely passing, and are treated as the infraction called "weaving". Three lane changes (1 1/2 "passes") within one minute is one of the criteria police have used for issuing such citations.

Comment Making trains run on time. (Score -1, Troll) 277

Those were actually Democrats. Learn your history.

While you may be historically accurate, you omit the fact that the Democrats and Republicans have essentially switched ideologies since the Lyndon Johnson administration, if not earlier.

Wrong - at least on civil rights.

But the Democrats have a lock on the media and academia. So (while they used the mechanisms of the Great Society to destroy the black family structure and reduce the bulk of the black population to a government-dependent, jobless, ghetto-dwelling, reliable voting block) they taught that the parties had swapped ideologies - and that the Republicans' attempts to enable people to rise from poverty were self-serving exploitation.

Don't believe it? Look at their voting record on anything REAL relating to freedom and equality before the law, even today.

It's similar to what happened in Italy in WW II. Mussolini didn't REALLY make the trains run on time. He made the newspapers SAY he made the trains run on time.

Comment FTFY (Score -1, Troll) 277

If left-wingers can justify punching out people they disagree with then they can just as easily justify beating the crap out of Pai.


(Note that the issue of whether right-wingers can justify punching out people they disagree with doesn't arise in this case. So don't bother following up to discuss whether I'm suggesting that right-wingers are less likely to escalate from discussion to beating the tar out of people or just that they mostly aren't disagreeing with Pai.)

Comment Same speed in same lane good, different lane bad. (Score 3, Informative) 404

Keeping constant spacing and running at a reasonable speed within a lane may be good. But holding the same speed in adjacent same-direction lanes is very bad.

In driving classes, back in the mid-20th century, we were warned against it. You NEVER were to hold the same speed as a car in an adjacent lane. (About a 5 MPH drift, with leftward lanes faster, was close to ideal.) Judging by the behavior of current drivers on California freeways that lore has apparently been lost.

Some of the issues:
  - Adjacent cars form a multi-lane "rolling roadblock". Drivers behind them who wish to travel faster are impeded, collect behind them, and end up "compressed", setting up the conditions for a chain, reaction multicar pileup.
      - With an inter-lane drift a driver wishing to pass a slower car soon has an opening to switch lanes and proceed.
      - With the slowest lane to the right and increasing speed to the left, merges and exits require less speed change and have better timing margins, long-distance traffic proceeds rapidly with little disturbance, and lane changes are easy. Drivers have the opportunity to rapidly distribute themselves among the lanes and drive at a speed where they're comfortable.
  - When driving at the same speed as an adjacent vehicle you increase your risk of collision:
      - If you're in a blind spot you STAY in the blind spot for a long time. The window of opportunity for the adjacent driver to happen to make a lane change into you - or into the space immediately in front of you, becomes much larger than if you had a relative drift.
      - If you hold relative position the other driver's peripheral-vision motion detector doesn't keep him aware of your presence. After a minute or so you're likely to fall out of his attention. Then, if a sudden traffic situation makes him need to change lanes suddenly (or he just wants to change lanes and forgets to do a recheck), he may swerve into you.

(By the way: The two-way two-lane equivalent of the rolling road-block chain-reaction-collision precursor is the "rat pack", a term of art in traffic engineering. It occurs when the first driver goes slightly over the limit and the second driver won't pass because he doesn't want to risk the necessary speed, but follows too closely for following cars to pass in two single-car hops. Fault is primarily on the second driver.)

Comment Re: Like someone else illustrated (Score 1) 440

Fahrenheit designed his scale in 1724. They weren't salting the roads and nobody was going fast enough or on a smooth enough surface for road salt to matter.

I didn't say it was by design. It's a convenient fallout of the arbitrary choices he made when coming up with a scale for his freshly-invented mercury-in-glass thermometer.

Road salt doesn't reduce that point to 0 F. Yes, but it's close. (The scale was originally designed with ammonium chloride, anyhow.) you can't maintain the salt concentration that high. Not a problem: They distribute gravel-sized chunks of salt, which take a while to dissolve even in running water. These melt randomly located and sized holes in the ice, which gives it a non-smooth texture (for traction) and breaks it up (for plowing aside).

Hyperthermia starts at 104 F which (with a basal metabolisim equivalent to running a minimum of a 75-watt bulb in your guts and head) you reach real-soon-now when the temperature is about 100F and you're dehydrated and the real normal body temperature is 98.6 F No, it's not. That's the typical measurement under the tongue - somewhat cooler than the core of the body, thanks largely to mechanisms to cool the brain. Subtract about a degree (97.6) for axilary (underarm) rather than oral, add about a degree (99.6) for rectal - which still isn't the hottest part of your core.

Yes, they're both approximate, so you have to use care as they're approached, as well as when they're exceeded. But how nice that a round number tags the (even if approximate) transition into unusual danger.

Comment The Dutch have done this for a while. B-) (Score 4, Interesting) 141

The Dutch have expanded into the ocean and used wind power for quite a while.

They've expanded their country by building dikes, pumping out water using windmill pumps, and reclaiming the seabed.

Building an artificial island and surrounding it with windmills to generate enormous amounts of electrical energy (rather than, say, building nuclear reactors) is right in character. B-)

(Back in the mid 20th century, one of the Lampoon magazines had a joke conspiracy theory article about the Dutch taking over the world by expanding out into the ocean and pushing the water up onto everybody else's country. It somehow involved people in other countries being awakened by the sound of chainsaws, wielded by invading Dutch military squads, being applied to their kitchen doors (to convert them into the two-segment, house-ventilating, "Dutch doors").)

Comment Re: Like someone else illustrated (Score 2, Insightful) 440

Customary are far more convenient for the tasks they're optimized for.

The Farenhiet scale is another example, where the definitions make the scale a strong mnemonic for certain situations:

  * 100 was set as a best guess at the time for the human body's internal temperature. (They got within a fraction of a degree.) When temperatures approach or exceed 100 F, it isn't enough to just relax when you're getting overheated. You must stay hydrated or suffer heat stroke and risk death.

  * zero was set at the coldest temperature they could easily and repeatedly generate in a lab: The melting point of pure ice saturated with salt (at sea level pressure, etc.) This is important when driving in states that salt their roads in the winter. When the temperature in degrees F goes negative the salt stops working. Drive VERY carefully or you end up in the ditch, risking death.

Given that those situations are deadly AND rare, it'37.s nice that these easy to remember round numbers flag them. Meanwhile, the boiling and freezing points of water (212F and 32F) are used often enough that they get memorized. With C, 100 and zero are boil and freeze, but will you remember 37.777... and -17.7777 as important numbers for heat stroke and deadly road conditions?

Comment Re:Sounds like people need to educate themselves (Score 2, Interesting) 275

Take an active role in your health care and question why you can't use a generic ...

And remember that, for some things, you really shouldn't use the generic - even when the FDA and your insurance company say it's just fine.

For example: Synthroid. This is a drug where:
  - the activity level is critical - you're replacing (all or part of) an important signal in a broken (or degraded) feedback loop with a constant output
  - but (unlike insulin) the tests are not easy enough to do real-time to recreate the feedback loop - so you take them every few months and adjust accordingly
  - being off too far can cause permanent neurological and other damage
  - the generic formulations are often far off the claimed dose, degrade at a different rate than the brand-name drug, or (in some cases) appear to be counterfeit with no activity whatsoever

Comment Exactly? (Score 3, Interesting) 275

... more importantly, you are guaranteed it will have exactly the amount of niacin it says on the label.

If I have this right:

Actually, you're guaranteed that the company did tests that show that, if it is not beyond the expiration date and hasn't been improperly stored, the drug will have at least 95% of the activity it claims on the label (for the on-label applications).

That's a heck of a lot tighter than OTC vitamins (even absent fraud). But let's be careful about saying "exactly".

(Lots of drugs are still quite potent far beyond their labelled expiration dates, though you don't necessarily know HOW potent. The manufacturing-to-expiration time is often when the company decided the formulation had adequate shelf life and stopped paying for testing, rather than the point where the drug degraded enough that it was close to missing the potency requirements.)

Comment Re:Lack of Metal (Score 1) 192

Umm...how do electronics work without metal? Are they using tubes of salt water as conductors instead?

They don't have ENOUGH metal - especially big enough pieces of thick, long, highly-conductive metal, to significantly affect the low, penetrating, radio signals used by the "metal detectors".

A large coin might possibly set one of these detectors off. A piece of electronics the same size or smaller, with plastic case, fiberglass printed circuit board, and fine wires shorter than the circumference of that coin (on the board or even tinier from point to point within the chips) is a much harder to "see" target. If the battery isn't enough to set such a gadget off, the whole phone would be only slightly more "visible".

The metal detector has to be INsensitive enough that it doesn't go off from dental fillings - or it would be going off all the time, and thus be ignored as useless. Make a phone that's a "smaller" target than a mouth full of metal and you can expect it to be missed, too.

Comment Re:How do you map non-invasively? (Score 1) 28

One stock device for cardiologists is synthetic-aperture doppler ultrasound sonar imaging

Alias "echocardiogram". I get a couple of these per year just for screening:
  - One resting.
  - A couple more as a "stress echo" - one just before and one just after a session on a treadmill (or an injection of a drug if my leg joints are acting up) to pump up the heart rate and dilate the vessels.

I also get (using the same or a similar system) occasional measurements of blood flow in various vessels, such as major arteries and veins, especially leg veins (looking for valve failures that might lead to clotting and heart attack) and the first fork of the carotid artery (where atherosclerosis can start up, leading impaired blood flow and brain damage or clotting and stroke).

It's also good for imaging all sorts of soft organs, such as kidneys (looking for things like cysts or cancers), a foetus (looking for prenatal problems), etc.

Comment Re:How do you map non-invasively? (Score 5, Informative) 28

I'm really curious how you can map a heart without actually touching the endocardium.

Just off the top of my head:

There are a number of non-invasive imaging technologies that can be "strobed" in synchronization with the heart's motion to produce a series of 3-D images which, together, amount to a moving picture of the cyclic activity, complete with various annotation (such as blood velocity maps, electro-chemical activity, etc.).

One stock device for cardiologists is synthetic-aperture doppler ultrasound sonar imaging. A wide hand-held probe, with the junction to the skin joined by a slimy jelly with about the same speed-of-sound as soft tissue, connected to a high-end laptop running appropriate software, can construct such mappings in real-time, in sessions lasting minutes, annotated with blood flow information.

Other possibilities include magnetic resonance imaging (the functional version if you want to visualize the cyclic electrochemical activity) and computer aided tomography scanning.

And that's just for starters.

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"The fundamental principle of science, the definition almost, is this: the sole test of the validity of any idea is experiment." -- Richard P. Feynman