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Comment: Re:not hard cosmic radiation (Score 2) 112

by slew (#47708171) Attached to: Scientists Find Traces of Sea Plankton On ISS Surface

Yes and no-- Depends on what the ISS's orbit is. If it has a circumpolar orbit, (crosses the polar region), then it will pass through the magnetic field lines that funnel cosmic particles into the atmosphere that cause the northern lights. EG-- it would get beamed pretty intensely with concentrated cosmic particles.

If it does not have that kind of orbit, and instead stays around the equator, then no so much. Mostly radiation free, compared to outside the magnetosphere.

ISS orbit track here... Quite equatorial...

What we need to do, is send a lander to the moon loaded with some microbial and planktonic colonies, where it can get beamed by high intensity, raw solar wind radiation, (And more importantly, where we can keep close tabs on it easily) and measure how the colonies do over time.

Accidentally did that back in '67 with Surveyor 3...

The 50-100 organisms survived launch, space vacuum, 3 years of radiation exposure, deep-freeze at an average temperature of only 20 degrees above absolute zero, and no nutrient, water or energy source. (The United States landed 5 Surveyors on the Moon; Surveyor 3 was the only one of the Surveyors visited by any of the six Apollo landings. No other life forms were found in soil samples retrieved by the Apollo missions or by two Soviet unmanned sampling missions, although amino acids - not necessarily of biological origin - were found in soil retrieved by the Apollo astronauts.)

Comment: a few grams of tritium a problem? (Score 2) 289

by slew (#47708051) Attached to: If Fusion Is the Answer, We Need To Do It Quickly

If it were only just getting a few grams of tritium, it isn't that hard to do. On the scale of a few grams you can just get something like this baby and hide it in a commercial seawater desalinization plant to get a few grams after a bit of time (and energy)...

Of course that isn't the most economical way to do it. I think a common military-industrial method today is to put lithium control rods into an experimental-sized fission reactor and collect the tritium gas that comes off... Still no fusion necessary...

Comment: Re:Explains how Merkel was very calm (Score 1) 168

...when it became known that the US were bugging her phone. Probably her reaction was "What's the hubbub, it's not like we don't...".

Of course when things like this become public, you have to make a good show, though...
Feigning outrage and going viral. Isn't that what the modern internet is all about?

Comment: Re:Stupid (Score 2) 194

by slew (#47705663) Attached to: Phoenix Introduces Draft Ordinance To Criminalize Certain Drone Uses

I also have the right to record what I see.

Sadly, you do not have the absolute right to record what you see. For instance being in your hotel room and having someone film you from a peephole in the door. Even though you might be able to see it when you are standing in a public place, you have no right to record what you can see.

If the subject of the photography is in public (as opposed to a publically accessible, but privately owned place), courts have basically ruled the subjects have no expectation of privacy, so most photographic recording is fair game. This is how paparazzi get many of their photos legally...

If the photographer is in a non-public area (e.g., the publically accessible, but privately owned hotel hallway), courts have ruled that public access rules do not apply.

The grey area is when the subject is in a non-public area, but the photographer is in a public area (e.g., a drone in "public" airspace, above a private residence).

AFAIK and IANAL, the line is generally drawn that invasion of privacy requires a recording device of some sort in these situations. It stems from the idea that invasion of privacy requires the publicizing of private life of an individual that is offensive to a "reasonable" person and/or not of legitimate concern to the public. I suppose w/o a recording device, you often cannot effectively publicize it so it falls outside typical invasion scope... And of course the definitions of "offensive" and "reasonable" are generally left up to the courts to decide...

Comment: Re:Surprise? (Score 1) 568

by slew (#47700025) Attached to: Munich Reverses Course, May Ditch Linux For Microsoft

In fairness, there are at least two ways that could happen:
1) MS bribes people to complain. Unlikely, but not impossible.
2) MS bribes the relevant officials to *say* there have been overwhelming complaints. I mean, there are inevitably going to be complaints; that happens any time *anything* changes. The question is at what point they become important enough to sway the overall decision.

With that said, I suspect you're right.


3) MS originally bribed officials to attempt to force ordinary people to Linux desktops knowing they would eventually complain enough to make the whole experiment fail and spin a cautionary for any that follow...

Or maybe not... ;^)

Comment: if a quality project can't raise money elsewhere (Score 3, Interesting) 98

If a quality project can't raise money elsewhere from more traditional fund-raising sources, might this indicate a subtle case of pre-selection quality bias instead of an indication of any anything to do with kickstarter campaign odds?

It could simply confirm that woman entrepreneurs often have less access to traditional funding sources because their industry contact lists are shorter in certain industries (which may or may not have anything to do with positive specific gender bias on kickstarter).

This is also consistent with the fact that in industries that tend to have more even female representation, they apparently lost the bias they were measuring...

I guess you can spin the results anyway you want...

Comment: Re:Seems simple enough (Score 1) 168

by slew (#47686785) Attached to: Processors and the Limits of Physics

Single isotope silicon? Silicon wafers surfaces (where the transistors are) are generally doped with ions using diffusion and etched, and the most serious defects are usually parametric due to patterning issues. We've go a long ways to go before actually isotope purity is going to be a limiting factor...

Conductivity of gold vs copper? Copper is a better conductor than gold (although silver is a better conductor than both of them). The reason that gold is used for *connections* is that it is more malleable than copper allowing it to make a more robust physical connection. For conduction, copper or silver is much better. The reason that silver isn't used today is that the processes needed to etch it are their infancy. Also, there's a reluctance to go there, because it's known that silver is much more prone to electro-migration issues than copper and the gain in conductivity is relatively small (compared from the step between aluminum and copper).

Also, silicon on insulator isn't w/o problems. The main problems today are the floating-body problem** which will likely render SOI impractical for devices that need high frequency switching (e.g, a CPU) in future process nodes. This is why after a brief commercial taste of this technology, many companies are moving away from it except for specialty products (like Z-ram).

Also, if your assertion is true that insulators don't conduct heat (very well), now you can't get heat away from one hemisphere of your circuit (instead of heat conducting up and down). Wouldn't that tend to make more problems than it solves?

**As I understand it, in bulk silicon, there is a leakage path that bleeds the capacitance away, but on an insulator, the body of a transistor is effectively a large parasitic capacitor. Failure to fully discharge the transistor body after switching creates somewhat of a memory effect limiting performance and potentially causing a parasitic transistors to drain floating nodes (e.g., in latches and xor-gates) in a operational sequence indeterminate way influenced by neighboring transistors. This makes it hard to margin for and may ultimately make it unworkable to obtain the tolerances needed for high speed design.

Comment: Re:Is that really correct?? (Score 1) 168

by slew (#47686653) Attached to: Processors and the Limits of Physics

200mV likely comes from a generic analysis of CMOS on Silicon wafer oxide assuming you don't want a leakage factor more than 50% the current (most of which comes from the subthreshold conduction current) and you don't do any weird body-biasing techniques (which would consume lots of circuit area). It isn't a hard number but a general ballpark. Since everyone is scaling down the supply voltage, we must also scale down the threshold voltage and then the amount a signal is below the threshold voltage when you are 'off' is now conducting at a level that is a significant fraction of when it is 'on' meaning the device no longer has much noise margin to work reliability at all.

Of course with different insulators and conduction semiconductors and transistor types and tolerance for leakage and reliability this will be different.

Comment: Re:Density limit - not computational limit (Score 3, Informative) 168

by slew (#47686591) Attached to: Processors and the Limits of Physics

Moore's Law is "the number of transistors in a dense integrated circuit doubles every two years". You can accomplish that by halving the size of the transistors, or by doubling the size of the chip. Some element of the latter is already happening - AMD and Nvidia put out a second generation of chips on the 28nm node, with greatly increased die sizes but similar pricing. The reliability and cost of the process node had improved enough that they could get a 50% improvement over the last gen at a similar price point, despite using essentially the same transistor size.

Bad example, the initial yield on 28nm was so bad that the initial pricing was hugely impacted by wafer shortages. Many fabless customers reverted to the 40nm node to wait it out. TSMC eventually got things sorted out so now 28nm has reasonable yields.

Right now, the next node is looking even worse. TSMC isn't counting on the yield-times-cost of their next gen process to *ever* get to the point when it crosses over 28nm pricing per transistor (for typical designs). Given that reality, it will likely only make sense to go to the newer processes if you need its lower-power features, but you will pay a premium for that. The days of free transistors with a new node appear to be numbered until they make some radical manufacturing breakthroughs to improve the economics (which they might eventually do, but it currently isn't on anyone's roadmap down to 10nm). Silicon architects need to now get smarter, as they likely won't have many more transistors to work with at a given product price point.

If memory-bound problems start becoming a priority (and transistors get cheap enough), we might see a shift back from DRAM to SRAM for main memory.

Given the above situation, and that fast SRAMs tend to be quite a bit larger than fast DRAMs (6T vs 1T+C) and the basic fact that the limitation is currently the interface to the memory device, not the memory technology, a shift back to SRAM seems mighty unlikely.

The next "big-thing" in the memory front is probably WIDEIO2 (the original wideio1 didn't get many adopters). Instead of connecting an SoC (all processors are basically SoC's these days) to a DRAM chip, you put the DRAM and SoC in the same package (either stacked with through silicon vias or side-by-side in a multi-chip package). Since the interface doesn't need to go on the board, you can have many more wire to connect the two, and each wire will have lower capacitance which will increase the available bandwidth to the memory device.

Comment: Re:Alpha Particles (Score 1) 168

by slew (#47686469) Attached to: Processors and the Limits of Physics

So just why would alpha particles (which are basically a helium nucleus consisting of 4 really heavy particles) gonna be somehow faster than electrons (which are much lighter and take less energy to manipulate)?

Another problem is that we aren't currently using free-space electrons either, but electrons in a wave guide (where we lay down conductors to steer the electrons around the circuits we design). Not as easy to do with alpha particles...

Comment: five points? (Score 2) 212

by slew (#47686409) Attached to: Figuring Out Where To Live Using Math

It may be affordable and walkable, but would you actually want to walk there?

I've always been weary when I took the RTD to the light rail station there at night and the crime statistics tend to bear this caution. Not to say it might not be some sort of up-and-coming neighborhood (don't live in Denver now so my information is a few years old), but historically, that's been fits-and-starts for that area with little progress since the '90s even though downtown was getting all the ball-park redevelopment...

On the other hand Capitol Hill in Seattle doesn't seem nearly as bad. It isn't the greatest neighborhood and although I don't generally wander around that area at night when I travel to Seattle (although I did occasionally drive by there because I know someone who used to have a restaurant there). I wonder how much crime got factored into this so-called walkability "math"... I'm a bit suspect of this WalkScore anyhow as it yields very unexpected ratings for the last few places that I lived...

Comment: Re:100 percent bullshit (Score 1) 199

by slew (#47682411) Attached to: Involuntary Eye Movement May Provide Definitive Diagnosis of ADHD

No, you used the term "slippery slope" correctly. The very premise of your slope is flawed. As a society, we've had mind altering drugs that directly stimulate our reward centers for as long as we've been a society. Nearly everyone takes some kind, but we still have an incredibly small percentage of people looking to use the harder stuff (antidepressants, ADHD drugs, street drugs). Given this history, it seems highly unlikely that we're heading toward a future of "mechanized work/play" any time soon.

FWIW, historically, Opium dens and crack houses did not consume much more than a small percentage of actual people, but it was significant enough to cause wide-spread effect on the population as a whole. Just because we aren't headed toward a future of "mechanized work/play", doesn't mean that the slope isn't slippery, it's just that you aren't likely to slip too far, but even then some might not like the consequences of slipping a small amount (depending on your definition of "small")...

Comment: Re:I would be very interested... (Score 1) 199

by slew (#47682377) Attached to: Involuntary Eye Movement May Provide Definitive Diagnosis of ADHD

Although you might disparage so called anti-ADHD people as being as a group ignorant, likewise some ADHD proponents exhibit a lack of knowledge of analogous medical anomalies like antibiotic abuse, or even somatic and conversion disorders (including, Münchausen syndrome or Münchausen syndrome by proxy)...

FWIW, it appears (to me anyhow) the current diagnostic of ADHD is problematic in that it is really an attempt to categorize a vague set of symptoms (effectively a syndrome) and associate this with a generic treatment plan. This is not unlike having a fever, stomach aches, etc and looking for some sort of pre-emptive and/or palliative cure in antihistamines and antibiotics (instead of perhaps waiting for a bacterial culture to verify the diagnosis before taking antibiotics). Sure some of those with symptoms might have TB or Salmonella poisoning, or have cold that results in secondary bacterial infection like pneumonia, so you can't rule that out, that possibility doesn't make it an inevitable (although personally, that's happened many times to me).

Studies like this ADHD study can really help to improve the situation greatly and hopefully result in a diagnostic tool that has much higher predictive powers for designing treatments rather than broad-spectrum palliative medications that can be over-prescribed and potentially have a net-negative outcome.

With more discrimination, sometimes newer treatment will emerge (like Neuraminidase inhibitors like Tamiflu did for actual viral influenza) that actually start to clinically improve outcomes (rather than just vaguely mask symptoms). In the meantime, palliatives are generally tradeoffs and if Ritalin actually helps a patient's situation relative to the side-effects, it is certainly useful, but as we can see with the anti-biotic over-use fiasco, the patents (or even the doctors) aren't necessarily always capable of making good tradeoffs in many cases, which leads me to be skeptical generally of ADHD being as wide spread as it is diagnosed (and similarly treated)...

My wife is a doctor and I know from her there is still strong bias and pressure to preemptively prescribe anti-biotics in the medical community (both from patents and over-worked doctors) even with all we know now... The main reason given... Just in case, side-effects are usually minimal, cannot treat the underlying virus anyhow and want to do something...

I suspect many feel the same is true with ADHD. It isn't that a brain/body disorder analogous to ADHD doesn't exist, it's just that we must be careful what we are trying to treat and why since we do not yet have the best diagnostic tools available to distinguish this disorder from other disorders for which we do not know the cause only symptoms, nor do we have a great understanding of the treatment outcomes relative to a specific underlying cause.

I am not now, nor have I ever been, a member of the demigodic party. -- Dennis Ritchie