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Comment Of course. (Score 1) 110

First everyone wants body cams.
Now everyone is complaining about it.
I knew this would happen. Can never please these people.

Besides, Body cams are typically only turned on during contact.
There is just to much video to store and sort thru.
We had to setup taser body cams and https://evidence.com/
They dock on a rack and upload the data when docked.

Comment I'm doing it right (Score 1) 325

I'm working on a system now, and for the first time in my career, I'm taking the time to really do it right (mostly because, for the first time in my career, I'm being allowed to). Even though it's mostly used in-house, we do have outside customers with access so I do make sure it runs acceptably on slow connections or devices.

Images are small and scarce. That's not exactly a big deal these days, but honestly, it makes styling easier.

There is one CSS file. It caches just fine. I just ran a test simulating a 22kbps connection - the first page load is about ten seconds, but after that, nothing takes more than a second or so to load, save for one page I've already marked for revision.

Javascript is minimal, mostly used to make nested menus load with AJAX or to do form submission with nice validation. This saves bandwidth overall, so I'd call it a win. The site does not degrade gracefully without Javascript but it doesn't require that much CPU horsepower to do what we do with it.

There are no ads or tracking. Not even Google Analytics. The designer wants to add it but I'm not gonna let it happen. We have server logs we can analyze for all the info we need, why would we send that on to Google, not to mention the perf hit?

Tested in current versions of Firefox, Chrome, Opera, Vivaldi, and Edge, and also IE10, under Windows and Linux (for browsers that run on Linux). IE misses some styling features, Firefox has some alignment glitches I haven't gotten around to yelling at the designer to fix it yet, but everything is fully usable. Safari and OS X testing will happen if we ever get a Mac to test with. Mobile browsers technically work but the site is very information-dense and nobody in their right minds would use it on a phone. (And I've tested it with Lynx, you can read it but it's not easy, and saving stuff is broken... if I ever run out of stuff to do, I might fix that, but it's not exactly a priority)

On a normal business-class internet connection (25Mbps shared across a dozen people), and a normal business-class browser (dual-core, 8GB RAM, Windows), most pages load in about 30ms. Only one takes longer than 100ms, and that's already queued for revision.

The fundamental problem is that too few programmers have a direct profit incentive to make a good website user experience. The big sites make money from ads, which are inherently anti-user. Contractors (which I used to be) care more about getting it out under the hours estimate than about quality. I work directly for the people who use this site eight hours a day, you can bet your ass I'll make this a good site for them to use.

Comment Re:Can someone explain the turbine here? (Score 3, Informative) 139

It's a fuel pump. Unlike a reciprocating engine, where you can inject the fuel at low pressure and then compress it, a rocket engine has to inject the propellant at the same pressure it's burned at, and thermodynamics wants that pressure to be as high as possible in order to get maximum efficiency (imagine a car engine that injected fuel at the top of the cylinder stroke instead of the bottom). Combined with the sheer amount of propellant being used, that means you need an absolutely insane amount of power in your fuel and oxidizer pumps.

So they use a turbopump. A small amount of fuel and oxidizer are tapped off and burned. The resulting hot CO2 and H2O are used to run a turbine, which drives the pump. In the Merlin engines, and in many other engines, it ends up just exhausting, generating no additional thrust. Other designs, including Raptor, find ways to re-use that exhaust to generate a bit more power.

Comment Re:Welcome to the Osborne Effect (Score 4, Interesting) 136

Good theory, but I think you're wrong. That's not what's hurting Microsoft - Sony did the same thing, with rumors of the "Neo" appearing shortly after the console itself launched. And yet the PS4 still sold quite well from day one.

What hurt the Xb1 is that it's demonstrably weaker than the PS4, but cost significantly more at launch ($500 compared to $400). Most games are available on both, so the natural inclination is to go with the cheaper and more powerful console. With a wide library of shared games, there's lots of direct comparisons to make, and even before they launched, it was easy to tell the PS4 would be more powerful. That gave the PS4 a very strong advantage during the first year or two.

Even now, they only have price-parity, with both having an entry price around $250-$300. But more people already have a PS4, making that the more attractive option both for multiplayer gaming (if all your friends are on PS4, you'd want one too) and for the larger percentage of third-party exclusive titles (it's nowhere near as big a deal as it once was, since porting is so easy, but there's still some studios that are deciding to skip the Xb1 because the audience is smaller). And it seems to me (as a non-Xb1, non-PS4 gamer) that Sony's shoveling the money from their console sales into more first-party games, giving it a still stronger library, which is ultimately what every gamer cares about.

Microsoft doesn't have a lot of options for coming back from this, just as the PS3 struggled to come back from the Xb360's early lead and the XbC never came close to the PS2. They could make the Scorpio be *substantially* more powerful than the PS4 Pro, making it more future-proof and maybe able to handle 4K/VR better. They could slash the price, and hope to catch up that way, but that's a risky move. They could pin it on VR or AR, but that's riskier still. They could double-down on their cross-play with PC bets - make every single Xb1 game PC-compatible and bundle a PC version, which would widen their library (although it would cannibalize Scorpio somewhat). Or they could go on a spending spree and buy up every developer they can, and kill off the PS4's third-party support - Sony is no Nintendo, they can't survive on first-party games alone (even Nintendo might not do so much longer).

Comment Re:Good for SpaceX (Score 4, Insightful) 75

You can have $70M of your taxpayer dollars used on his rockets, or you can have $160M of your taxpayer dollars go to Lockheed Martin and Boeing. Your choice.

So:
* Cheaper by 55%
* Built entirely in America
* Doesn't give money to a country we're sanctioning
* No design elements from the 1970s
* Company is doing innovative things to drive down costs even more in the future
* Slightly more likely to explode

Seems like a good thing to me.

Comment Re:Title is wildly misleading (Score 4, Interesting) 107

Solid rocket motors have tradeoffs. In some circumstances, they make sense.

They are long-term storage-stable. Build it, stick it in a silo somewhere, and leave it be for a few years, it will still launch just fine. Hypergolic liquid-fueled rockets can't be kept ready-to-launch for more than a few days*, and cryogenic liquid-fueled rockets can't be kept ready-to-launch for more than a few hours. This makes them particularly preferable for military uses, everything from little anti-tank rockets to ICBMs. This also reduces the number of ground crew needed - you don't need to worry about fueling, just electricals and signals.

They have extremely high levels of thrust, due to the extremely high energy density. The Shuttle's SRBs were each twice as powerful as the largest liquid-fueled rockets. This makes them very popular as boosters.

They have a lot of impulse per unit volume. What most rockets care about is impulse per unit mass (aka specific impulse), but some cases care about volume. If you're launching from an aircraft, like Stratolaunch or Pegasus, this matters. If you have constrained volume because you're in a fixed-size fairing, this matters. If you're launching from a submarine, this matters.

It's also often a matter of economies of scale. Countries with military missile programs (which have many reasons to go solid-fueled) often use them for other things as well, either to subsidize their military-industrial complex or to take advantage of existing scale to make civilian rocketry cheaper, depending on how cynical you are. The US, masters of solid-fueled ICBMs, used a pair of massive SRBs on the Space Shuttle, and will use them again on SLS, if that ever flies. The ESA's Ariane 5 uses SRBs based on a French SLBM. Japan may not field ICBMs, but they too have a reason - the first stage of this rocket is almost identical to the booster of their H-II rocket.

The higher stages are solid-fueled presumably to maintain that low-ground-crew capability, and the minor reduction in drag can't hurt either.

Comment Re:"self investigate" == alt.right (Score 1) 789

The difference, as I see it, is that "incorrect news" or "wrong news" lacks malice - it may have been wrong, but it was intended to be true, and either accident or negligence caused it to not be. "Fake news" was known by its peddler to be false, and yet was pushed anyways because The Cause mattered more than The Truth.

Comment Re:National instant-runoff (single transferable vo (Score 1) 637

You are mistaking cause and effect. The third-party candidates suck BECAUSE we have a tiered FPTP system. Anyone smart enough to be a viable third-party candidate is smart enough to know that the best way to help their cause isn't to run separately, but to try to assimilate their cause into one of the major parties. If we had a system that eliminated, or at least ameliorated, the spoiler effect, smart and capable people could run as third-party.

Comment Re:Condorcet's Voting paradox (Score 2) 637

A Condorcet paradox is not guaranteed to exist in any given set of candidates and voters. In many cases, there can be a candidate who would win a 1-on-1 simple-majority election against all other candidates, and is thus clearly preferable - and there are voting systems that are guaranteed to elect that candidate *if* they exist. Simple plurality (aka first-past-the-post) is NOT one of the voting systems that can find such a candidate, and in fact is probably one of the worst systems possible for finding the more preferred candidate.

The fact that there cannot be a "perfect" voting system across all possible sets of candidates and voters does not mean that there is no difference in quality between the real voting systems that we have to choose between. There is indeed a vast difference between this crazy, unevenly-proportioned multi-level plurality system we've inherited, and the more modern voting systems such as instant-runoff, two-round, approval, or range voting.

(And when you consider the expense that we go to during our electoral campaigns, we quite clearly can afford to replace our voting system.)

Comment National instant-runoff (single transferable vote) (Score 5, Insightful) 637

The electoral college is obsolete. The transportation/communications difficulties it originally solved are long gone, and the laws forcing electors to vote a certain way have rendered moot the additional check on demagoguery it was intended to be. Now, it's just a way for a minority of obsolete voters to get an outsized say in national politics. Eliminating the electoral college should go without saying. But why assume that we must use a simple plurality of the popular vote?

I propose replacing presidential voting with instant-runoff voting (equivalent to single transferable vote in elections with only one winner, which this is). It's a proven system that's been used in many other countries, quite successfully.

The system is simple. It's easily explainable - everyone ranks their choices, from best to worst, and then if any candidate wins more than half of people's top vote, they win. If not, the candidate who performed the worst is crossed off, and we check to see if anyone has a majority, repeating the process until we have a winner. It's simple enough to be easily usable with paper ballots and manual counting, and requires only a single round of votes to be cast. But it has all the advantages of the more complicated voting systems.

IRV/STV eliminates many of the problems we've seen in American politics:
1) Third parties can be more competitive, because without the spoiler effect, they don't have to convince voters en masse to defect to them, just that they would be better.
2) It separates agreement with the person and agreement with their politics. Clinton and Trump were both widely disliked as people, but they captured huge swaths of the vote simply because people agreed with the vaguest outline of their politics, as denoted by their party affiliation, and had the belief that the only practical way to support those politics was to vote for that candidate despite their personal problems. Had Democrats had a chance to vote for Sanders or Warren, with Clinton as a backup, they would have done substantially better - and perhaps Republicans would have performed better if Kasich or McMullin had been able to be people's primary pick, with Trump as a backup.
3) It encourages moderatism and discourages extremism. Because votes transfer from the weakest candidates to the strongest, and the weakest candidates are usually those at some extreme, it generally transfers votes from candidates at the far left or far right, towards the center. This is a weakness of the system in that it makes the system slow to drastic change, but it is still better than our current system which is nearly as slow to drastic change, and is worse at handling minor changes as it usually overshoots.

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