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Comment Impossibility of access (Score 1) 112

Before encrypted electronic communications, criminals and terrorists had to use things like in-person meetings or unsecure communications methods (like analog telephony) to communicate. These were obviously vulnerable to being listened to for a determined party, but that was simply how it was, there was no other option. Law enforcement could use various human-powered means to target specific individuals or organizations, like tapping a particular phone line and having a human listen to it when it went active, or maybe stake out a particular meeting place with some high-power microphones. For the general non-criminal population, while it was technically possible for the government to listen to everyone all the time, it was realistically impractical because of the vast amount of manpower it would require.

Today we're in the opposite situation. Law enforcement can now get ahold of all electronic communications through various taps, but if criminals and terrorists use the proper technology and best practices, it is *impossible* for law enforcement to know what is being said. (Yes, deep-cover operatives are still possible but are impractical for all but the absolute highest-priority things for reasons of time, risk, and the same old manpower problem).

I don't have a great answer. Anything is either too insecure or seems too vulnerable to corruption. The only thing I've come up with is third-party escrow of encryption keys, but who is the third party and how do we know they aren't corrupt?

Comment Re:How about 18 minutes without the tunnel? (Score 1) 155

Here in Seattle's 405 loop, our DOT added tolling to the HOV lanes with this sort of variable pricing about a year and a half ago. Result? $10 for a one-way trip during rush hour for just 15-20 miles or so (not exactly sure of the distance). They hit the max price they promised the public, and was STILL too crowded.

Please learn from our mistakes. This doesn't work. People HAVE to get from Point A to Point B at a certain time every day, because their job demands it. It's going to happen, no matter what financial disincentives you put in the way.

Comment Re:Speaking of delays... (Score 1) 106

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:OMG (Score 1) 386

It's an entitlement excuse.

When I was in high school, I knew a lot of kids who worked at Burger King. They were stealing money from their registers, some of them managing to lift over $800/month. Everyone agreed this was a good thing because "they didn't get paid enough." High school kids. Not paid enough. Seriously.

The only excuse for using company time for non-work is not having work to do. You get an admin job and you're efficient enough to do it in 1/3 the given time? Well, I can't rightly say you've been stealing company hours if you're achieving 100% of your assigned work. Some offices even tell you to go home if you're done your work, and pay you anyway--they're legally-obligated to pay your salary if you're exempt, just like they're not obligated to pay overtime, so if you work 15 hours and get all your shit done and they send you home you still get paid. That actually makes sense.

What doesn't make sense is agreeing on and accepting a salary and then stealing time, money, or equipment from your employer under the claim that they're not paying you a fair wage. There is no fair wage. Market rates are rates people can't manage to push up from and employers can't manage to push down from. Businesses employ the lowest bidder, and employees go with the highest bidder. You took the bid? You agreed to this shit. Excuses like the distress of unemployment and the difficulty of getting a job just tell me you wanted to fasttrack the process and get bumped to the front of the line and you bought the front spot--that's what your lower-than-industry-average salary is: a privileged purchasing agreement.

Comment Re:Amazon has lost it's way (Score 1) 74

Yes, at Amazon.com, though obviously its only limited to searching for their products (which is practically everything). They display "sponsored results" that look just like the results you were searching for. It got so annoying that I configured some special rules in adblock-origin to strip out some of that crap, so I don't even know if they still do that.

I spend a lot of money at Amazon. It's really annoying that they feel they need to monetize my eyeballs as well.

Comment Re:What governmen brought to the table (Score 1) 106

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) 106

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) 106

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) 106

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) 106

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 Re:That's actually debateable (Score 1) 303

Manual-labor jobs they can. Office jobs require some downtime to refactor, and the 8-hour work day theoretically lets you mix that in so you can optimize it.

The more-scientific approach I've seen is to schedule high-effort, complex work in the mid-morning and around 2-5pm, with low-effort work put between 1pm and 3pm. The slump cripples your ability to perform productively, and so spending that time returning calls, checking e-mail, writing changelogs, and so forth lets your brain relax and recover so you can get back to designing rocket engines and writing complex computer code later in the afternoon. You wind up productive all day, doing the simple shit when you can't handle the heavy lifting.

The moral of the story? Do your code reviews and merge windows between 1pm and 3pm. It's less work than writing new code, and it keeps your head in the code so you're ready to hit the ground running right after.

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