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Comment Re:Well, sadly, probably.... (Score 1) 36

Many if not most employment contracts/agreements have verbiage that states that anything you come up with on company time, belongs to the company.

Many if not most employment contracts/agreements for software engineers and the like have verbiage that states that anything you come up with on company or personal time, belongs to the company.

Read your contract carefully before starting a side business.

Comment Re:60Ghz (Score 1) 109

I agree it sounds impractical. So I looked at the patent -- which not being a radio engineer it's perfectly safe for me to do (n.b. -- it's always dangerous to look at what might be bullshit patents in your field because you open yourself up to increased damages for using common sense). But I was a ham radio operator when I was a kid so I do know the lingo.

There are a number of problems with broadcasting power, starting with the fact that it's inefficient to saturate ambient space with enough radiation to be usefully harvested. But that's not what they're proposing. 802.11 ad operates in the extreme microwave range -- about 5cm wavelength aka the "V" band. This band is also unregulated so you can try weird things in it. What they propose is to use an array of antennas to create a steerable beam -- like a phased array radar. This would confine the power to a specific plane so that you wouldn't have to saturate all of ambient space with power. The beam steering would be done "dynamically", which I take to mean it would figure out how to maximize signal strength with some kind of stochastic algorithm. So it might not work if you are unicycling around the room.

And because the wavelength is so short an antenna array would be relatively compact.

Even so, it doesn't sound that practical. It's bound to be limited to line of sight, for example: the V band does not penetrate walls or the human body at all, in contrast with the S band that conventional wifi operates on. I can certainly imagine applications for it, but making it practical for charging your phone is apt to be very expensive. You'd have surround yourself with V band antenna arrays.

By the way, reading this patent reminds me of why I hate reading patents. They're infuriatingly vague in order to make the claims as broad as possible, and yet are cluttered with inanely obvious details ("the radio receiver can include active and passive components") and irrelevancies (the device may include a touch screen). I think the purpose may be that someone trying to figure out whether the vague language applies to a cell phone will think, "I don't know WTF this is claiming, but look this phone *does* have a touch screen." It just shows how broken our patent system is.

Comment Re: Favorable? (Score 1) 189

Going with your premise, why should Google and Facebook be permitted to track my usage of other sites?

They can't. Not shouldn't, can't.

What can happen is that when you visit some site that site may tell your browser to load a resource from Facebook or Google, and when your browser does so, they find out about the visit. Your browser even sends them a nice referer header. Alternatively, the site you visit may send a message to Facebook or Google telling them about your visit. Neither of those things require any eavesdropping on traffic not intended for Facebook or Google.

Comment Re:Speaking of delays... (Score 1) 79

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) 79

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 1) 79

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) 79

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.

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