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Comment Part of why Silicon Valley is in CA (Score 1) 338

Most employment agreements are such that the company owns it even if it is outside of normal hours. So inventions you come up with on your own time are not yours.

And one of the key reasons Silicon Valley grew up in California is a law that, in effect, says:
  - As a matter of the state's compelling interest:
  - If you invent something
  - on your own time and not using company resources
  - and it's not in the company's current or expected immediate future business plan
  - you own it
  - regardless of what your employment contract says
  - and employment contracts have to include a notice of this.

Result: People who invent neat stuff their current company won't be productizing can get get together with a few friends, rent a garage across the street, and build a company to develop the new stuff. So companies bud off new companies, doing somewhat different stuff, like yeast. And the opportunity to get in on the ground floor attracts many other skilled people who might not be as inventive, but still wnt to be some of those "few friends" of the inventors.

Comment Re:Need this refined before I need a knee replacem (Score 1) 46

Sooner or later I will need a knee replacement. It would be nice to have a tissue one instead of metal and plastic.

I could use one now. I tore a meniscus in my knee a couple years ago, and it's healed as much as it will - which isn't enough. Surgery options only involve cutting it out (which leaves the bones rubbing each other) or replacing the whole joint (which is not only inferior but doesn't last as long a my current life expectancy).

Being able to drop in a replacement, grown from a printed scaffold of generic materials seeded with my own induced-pluripotent stem cells, would just fix it. (In fact it should fix it to be as good as it was decades ago, or maybe even better than it ever was.)

Comment Single target. (Score 1) 41

All [no standard] means is that websites will write their own version, some already have.

Indeed.

Also: In the race between weapons and armor, weapons always (eventually) win.

By creating a standard and getting the bulk of the "content providers" to adopt it, the WWWC creates a single big target that leads to breaking MOST of the DRM simultaneously. Meanwhile, content providers are left with the choice of getting behind the big target or being non-standard.

Which is fine: Like WEP, or a locked screen door, DRM won't protect things forever. But, like a "No Trespassing" sign, it DOES indicate INTENT forever. Intent of the content provider to limit access, and intent of the unauthorized content viewer to bypass that limit. That takes the "I didn't mean to do it." defence away, and gets any legal cases down to examining whether the poster of the No Trespassing sign had the right to limit the access and/or the crosser of the boundary had a right to obtain access.

Comment Re:Speaking of delays... (Score 1) 104

ULA's track record with the Atlas V: 100%

Yes, let's take one vehicle in its fifth generation (not counting subrevisions), and ignore its track record with all of its earlier versions that led up to this point and all of their failures, and all of Lockheed and Boeings' other launch vehicles over time, with all of their failures. Lets also ignore that they're going to have to switch engines soon, to an engine with zero track record.

Payloads typically launch on schedule or within a few weeks. .... Some payloads have been waiting literally years due to delays.

Let's totally ignore that Atlas V launches once per two months, while SpaceX launches once per month, and that almost all of the wait time was due to investigation backlog. When it comes to hitting launch windows, SpaceX has a higher average success rate than average than Atlas V

And lets entirely fail to mention the point that ULA charges nearly double what SpaceX does per kilogram. Or that SpaceX is doing everything while rapidly evolving its rocket, to the point that they've basically even switched propellants partway through (denisification radically changes their properties). And while at the same time running an aggressive recovery and refurbishment programme and developing a heavy lift vehicle, with a small fraction as much capital.

Comment Re:What governmen brought to the table (Score 1) 104

As if liquid boosters can't fail catastrophically? Check out SpaceX's last failure. Liquids are hardly immune to catastrophic failure.

And actually more to the point, you've got it backwards. The SRB failure on Challenger was slow, more like a blowtorch. The explosion was when it compromised the external tank (which, obviously, stored liquids).

Solid propellants aren't like explosives. More to the point, you have to keep them under pressure to get the sort of burn rate that is desired for a rocket.

Comment Re:Speaking of delays... (Score 2) 104

Could you remind me how many people SpaceX has killed? Boeing and Lockheed have certainly killed people in the past.

If you're referring to the AMOS 6 ground failure, ignoring that part of the whole point of flying a stack unmanned as much as you can before you fly it manned is to shake out any problems, is that a manned mission would have almost certainly survived that. Unless the launch escape system failed, despite the drama, that was an eminently survivable. How do we know this? Because AMOS-6's hypergolic propellant tanks didn't ignite until the satellite hit the ground. AMOS-6 had the fairing as some extra protection, but on the other hand, the satellite itself isn't nearly as durable as a crew dragon.

The launch escape system ignites within milliseconds of a failure being detected and almost immediately reaches full thrust, accelerating away at 10gs. Here's a graphic of Dragon's abort test superimposed over the AMOS-6 failure. Things like this are the very reason that launch escape systems exist. NASA's last manned space vehicle lacked such a system entirely. And while their design for the Shuttle ultimately wasn't chosen, you know what? Lockheed's proposal didn't have one either. And it had a strong impact on influencing the final Shuttle design outcome.

Comment Re:What governmen brought to the table (Score 1) 104

SpaceX and Blue Origin would not use solids, not because there's something wrong with solids per se, but because they're not "fuel and go", which makes them expensive to reuse - and SpaceX and Blue Origin are all about reuse.

A lack of experience with hydrolox surely factors into the picture for SpaceX and Blue Origin; they'd get significantly higher payload fractions by using a hydrolox upper stage. But they're willing to accept lower payloads in order to simplify their manufacture and ground infrastructure, and in particular because the need their propellants to be storable, and storing LH for long periods is a PITA. Storing methalox is quite difficult, but nothing compared to hydrolox.

Comment Re:What governmen brought to the table (Score 2) 104

Solids really aren't that bad when reusability isn't a concern. They're very high thrust, which is exactly what you want out of a booster, and they're structurally very simple. Their low impulse and high structural mass are not particularly important aspects for boosters. Reuse of solids however gains you very little, because there's so much work in refurbishing them.

Comment Re:What governmen brought to the table (Score 3, Informative) 104

That's not the reason you don't use it for a first stage. The disadvantages of hydrolox (which are numerous) are offset by its incredible specific impulse. But for a first stage, specific impulse doesn't matter that much, while thrust matters a lot. Thrust is in large part proportional to fuel density, as a turbopump sweeps out a fixed volume per rotation, so the denser the fuel, the more mass (and generally all else being equal, energy) it pumps per rotation.

Another aspect is that first stages are big, meaning that cost is more important than specific impulse. By contrast, when dealing with an upper stage, a small increase in mass has a huge increase in first stage size, and since first stages are so large and expensive, that's a big cost. So you generally want a higher ISP upper stage. With the caveat that "storability" requirements for engines that need to restart can shift the balance; because hydrogen is so deeply cryogenic it's difficult to store for protracted lengths of time. Also, the longer you plan to have a stage in usage without maintenance, the more you tend to favour simple propellants over high performing ones, particularly when you're dealing with small, light engines. So for example if you have an interplanetary probe you'll tend to favour a self-pressurizing hypergolic system so that you only have to rely on a couple valves working, even though self-pressurizing propellant tanks are heavier and hypergolics tend to be lower specific impulse. Engines that are smaller still are often monoprops for an even greater degree of simplicity.

Comment Leeches are already back. (Score 1) 474

When will Trump bring back leeching?

They're already back. They're used in limb reattachment surgery post-operative treatment.

When limbs are reattached the arteries work well right away but the veins not so much. So they have poor circulation and inadequate oxygenation, especially at the finger and toe tips. This can lead to further cell death, infection, and transplant failure.

Leeches applied to the extremities of the limbs can pull out enough blood and bring in fresh to keep more cells alive and bring more infection-fighting white cells to the area. And leeches do little damage other than draining blood, and provide their own surgical tools and anaesthetic. (It's in their evolutionary interest to not bother the victim into pulling them off while they're feeding, and not leaving wounds that would make him tend to avoid the location later.) So raised-sterile leeches are used, with substantial improvement in reattachment success rates.

Comment Re:Storage? (Score 1) 474

To pick up where renewables leave off, you want natural gas (or even petroleum) turbines that can quickly be brought on and off line.

Also: If you really are concerned about carbon dioxide, they produce a lot less of it per unit of energy.

In fossil fuels most of the energy comes from burning the hydrogen to water. Burning the carbon to carbon dioxide provides some, but it's mostly useful for packaging the hydrogen. Oil and gas is essentially long-chain-of-carbon molecules with two hydrogens per carbon and two more to cap the ends of the chain (with occasional tree-structures with the same carbon/hydrogen counts, and the odd ring-shaped or multiply-bonded impurity that''s short one or two pairs of hydrogens.)

So oil is a little over two hydrogens per carbon, gas goes from about 2.5 (butane) to 4 (methane). But coal is essentially just carbon. So gas is best, liquid oil fractions are not as good (though convenient for mobile engines), and coal is worst, on the energy/CO2 production ratio.

Comment If coal is dead, killing its bueaucracy won't hurt (Score 1) 474

Coal is dead. ... trying to resurrect something ... dying [from] market forces ... is [perjorative].

This isn't about trying to resuscitate the coal industry (though if it lets it run a little longer and die more smoothly - rather than being suddenly assassinated in a fit of political vitrual-signaling - it will let the miners and their offspring migrate to other jobs, rather than to government assistance.)

It's about killing off the massive, expensive, and intrusive regulatory infrastructure that no longer serves any purpose.
If Big Coal IS being killed by market forces, the government needn't bother killing it off.

It also gives Trump the opportunity to keep a promise to some of his voting base, make political appearances claiming credit for it, and engage in some virtual-signaling of his own (conservative style).

Remember: He didn't promise to bring their jobs back (though if some of the jobs do come back, or existing ones not be ended as soon, it is a bonus). He promised to dismantle the regulations that had already killed jobs - and give a dose of job-killing medicine to the regulators.

I suspect schadenfreud will please his coal-state voters, and the prospect of voter revolts and sweeping reforms may make at least a few future regulators think twice before stomping jackbooted on the faces of those they regulate.

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