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Comment: Re:So (Score 2) 206

The point is to make the account cost more than the expected value gained via scamming.

Scams, in general, have a poor success rate. There may be a sucker born every minute, but there's 250 people born a minute. Even if a successful scam nets a large gain, losing $5 on each attempt makes it a losing proposition.

Comment: Re:Holy crap, that marketing spin (Score 1) 50

Uh, you sure you were searching for the Intel 750? Because Amazon lists it for $471 for the 400GB model, or $1200 for the 1200GB model. Which is quite a bit inflated from NewEgg's pricing but not exactly the $2400 you listed.

Oh wait, I should have read the rest of your post first. You have absolutely no idea what you're talking about, do you?

Comment: Focus on expert sites (Score 1) 260

by gman003 (#49501905) Attached to: Ask Slashdot: What Features Would You Like In a Search Engine?

I've started drifting away from using Google/Bing/whatever, in favor of loading a bunch of site-specific search engines into my search bar.

So if I'm looking for, say, a specific Magic card, I don't let Google search the entire net, and find everything that happens to say "elvish mystic", giving me a ton of irrelevant stuff (even searches like "mtg elvish mystic" bring up pages to buy one instead, which usually don't have the info I'm really looking for). Instead I click an extra button to go straight to Wizard's own database page for it.

Repeat that idea for about twelve different gaming wikis, plus Wikipedia for general knowledge, and you'll have the contents of my search bar. If I were into different hobbies, I might have similar search engines for those.

A single search engine that can figure out the context of the search, then go straight to the experts for that context, would be one way to do better than Google.

Comment: Re:Questionable engineering decisions. (Score 3, Informative) 73

by gman003 (#49501053) Attached to: Rocket Lab Unveils "Electric" Rocket Engine

Uh, the SSME engines ran off the same propellant as the rocket - LH2 and LOX. It's a staged-combustion rocket - some of the fuel and oxidizer flow was diverted to a preburner, which partially combusted them (the mixture was fuel-rich, limited by oxygen), ran the fuel-rich exhaust through turbines for the fuel and oxidizer pumps, then exhausted into the main combustion chamber where it was mixed with the remaining oxygen to complete combustion.

A better example for a separate propellant would have have been the V2 rocket, which burned ethanol and LOX, and had a pump powered by hydrogen peroxide.

Right on all other points, though.

Comment: Re:Specific impulse versus thrust (Score 1) 73

by gman003 (#49500903) Attached to: Rocket Lab Unveils "Electric" Rocket Engine

Not true. Measures of rocket efficiency almost always count losses to the pumps.

That's why gas-generator-pumped rockets (like the F-1, at 263s, or the Merlin 1D at 310s) are listed as less efficient than staged-combustion rockets (like the NK-33, at 331s). The rockets are measured as a full system, not at just the combustion chamber and nozzle.

This one, I would expect, has higher fuel efficiency per kg and lower thrust per kg. Not having to burn any fuel for non-propulsive purposes will undoubtedly help its fuel efficiency, but the heavy batteries will lower the thrust efficiency. That's just an educated guess though.

Comment: Cheap because of size, not engines (Score 2, Interesting) 73

by gman003 (#49500609) Attached to: Rocket Lab Unveils "Electric" Rocket Engine

Big rocket engines use big propellant pumps. The pump on the F-1 (used on the Saturn V) ran about 55,000 horsepower.

Electric motors won't do that cheaper. And they'll sap the weight of the rocket, since even a dead battery is heavy. Fundamentally, a big rocket will be better served by a gas-generator or staged-combustion cycle.

That's fine for this rocket because it's so small. The payload is 110kg. For comparable rockets, turn to Iran's unflown Simorgh, Israel's Shavit, or North Korea's Unha, all in the 100-160kg range.

To put those numbers in comparison, let's look at SpaceX. The single-engined Falcon 1 put 670kg into orbit. A Falcon 9 runs 10,000-13,000kg. And the Falcon Heavy is supposed to lift 53,000kg.

Or for an older comparison, Sputnik 1 weighed 80kg, and Sputnik 2 weighed 500kg. So they're building a rocket that couldn't even lift the second satellite to ever fly. I'm not particularly impressed.

Maybe there's a niche for small payloads like this, but in all honesty, I expect you could fly several such payloads on one bigger rocket, or just hitchhike on the spare capacity on a big satellite launch. Still, worth a shot. Just don't pretend to be playing in the big leagues.

Comment: Holy crap, that marketing spin (Score 2) 50

"unlike Intel's new NVMe solution, the Kingston drive will work in all legacy platforms as well, not just Z97 and X99 boards with a compatible UEFI BIOS."

So it uses AHCI instead of NVMe, and tries to spin this off as a benefit over Intel's drive.




AHCI dates back to 2006. It was an improvement over IDE, but it was still designed for spinning rust. No parallel queues, a paltry limit of 32 queued commands, and a design that puts a pretty substantial load on the CPU for each command used. It's something like 14,000 cycles spent in just the driver code for an AHCI command - compare 10,000 for the entire OS stack from fread() to actual bits going over the line for NVMe.

Now, it is true that NVMe isn't fully supported on older motherboards. But that's only boot support - an NVMe drive will work as a data drive on anything running a current OS (Linux 3.3+, Windows 7+). And guess what? Most motherboards that have an M.2 slot* to begin with... are NVMe-compatible. So if you're buying an M.2 drive, you can probably use the NVMe drive. And if you're building a new computer, you'll be getting one that works with NVMe.

Backwards compatibility is important. I'm not saying to discontinue SATA SSDs. But making an M.2 drive that still uses AHCI, then claiming the backwards compatibility as a benefit, is just pure marketing bullshit.

* M.2 is a weird physical interface that can be connected to up to three different interfaces - PCIe, SATA and USB. The USB is only really used for wireless cards, so that leaves PCIe and SATA. Unfortunately motherboards don't have to wire both up to the slot. You can find some cheap motherboards with an M.2 slot that only works with SATA drives. I personally refuse to count those as full M.2 slots. And both Intel's 750 (the NVMe one) and Kingston's drive being advertized here would not work in such a drive, so my point about "if you can put this drive in your computer, you can put a 750 in there and have it work" stands.

Comment: Re:Larger landing area (Score 1) 340

Horizontal velocity would still need to be killed. If it has too much sideways momentum at touchdown, it'll just drag and tip over, no matter how big the landing area.

SpaceX is, unsurprisingly, doing things the right way. The hard way, to be sure, but when they finally get it working by proper engineering, rather than overkill, it will be well worth it.

Comment: Re:Why a one-second launch window? (Score 1) 77

by gman003 (#49465957) Attached to: SpaceX Launch Postponed

That makes sense, and I recall that this is the most heavily-loaded Dragon yet, so less dV for orbital maneuvers would make for a shorter launch window.

And I did seem to be remembering things wrong - every previous CRS flight I could find a launch window for had an instantaneous launch window. I must have been thinking of the non-CRS flights.

Comment: Re:Ranto (Score 1) 624

That rant is a pretty fair (if harsh) criticism of Esperanto, but it doesn't really point out any irregularities in Esperanto itself. Many of the flaws it points out are actually cases where the language is too regular, where it mandates something everywhere instead of making it optional where possible.

The only grammatical irregularity in Esperanto I can think of is how -A affix can be used for female names, instead of the -O used for all other nouns. Other than that, everything is regular and self-consistent.

Comment: IFR vs VFR (Score 1) 460

by gman003 (#49422471) Attached to: Planes Without Pilots

There are two types of flying: instrument flight rules, and visual flight rules.

IFR is used at night, when the weather restricts visibility to under a certain amount (thick cloud cover can do this, no precipitation needed), on flights long enough that you can't guarantee VFR conditions at your destination, and just whenever you feel like it.

VFR is generally only used for beginning pilots or quick flights. It's sometimes seen as a relic of earlier times. Sure, you get taught how to fly this way, get taught some basic dead reckoning techniques, but nobody really flies this way, most of the time.

But instruments fail. Autopilots fail. Engines fail. When everything fails, you want someone in the cockpit who can look out the window, navigate by landmarks, and if necessary put the plane down on the straight sections of highway Eisenhower built to accommodate bombers returning from the Soviet Union.

When things go wrong, you want something smart and adaptable in control. There are procedures for damn near everything in aviation, but there's still things you can't pre-plan for. Until we get a general strong AI working, the only thing smart and adaptable enough is a human.

Now, that doesn't mean we can't have fully computer-controlled aircraft. It just means there shouldn't be people on board those computer-controlled planes. Drones are fine - even if it's a cargo-laden drone version of a 747, the loss of life it can accidentally cause is miniscule, compared to even a small passenger plane.

Technology is dominated by those who manage what they do not understand.