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Comment Re:Terraforming potential? (Score 1) 278

First off, you're misusing temperature. You don't call it heat if all of the particles are moving in the same direction and unionized, you just call it "wind". It only becomes heat if that windstream suddenly slams into a non-moving solid surface and becomes instantly thermalized (but of course even then that would be a very short-lived event as it would correspond with a pressure rise and the deflection of the stream behind the high-pressure zone). Additionally, nor would that be the windspeed touching the surface as, obviously, wind forms boundary layers.

Secondly, hundreds of km/s from Venus escape to Mars intercept? That doesn't at all correspond to any delta-V chart I've ever seen.

Comment Re:Nope (Score 1) 392

If they had it then collision avoidance would function at that speed but NOT if the driver is mashing the accelerator pedal like they were. Pressing the gas hard disengages the automatic braking with pedestrian avoidance - it also does so when in self parking mode as a safety feature should you be getting carjacked.

Comment Re:Misnomer (Score 1) 392

I assume, and I shouldn't, that "filling up" with diesel is more than your implied "some" which will, indeed, harm the engine. I have had friends who have somehow managed to do this and the opposite (putting gasoline into a diesel) and in all but two cases they have realized the error and had the vehicle towed, drained, and returned. In the two cases that I know of, where they did not notice, catastrophic engine failure was the result. Sadly one was a beautiful old Mercedes that she had borrowed from her father-in-law because her car was in the shop. A replacement engine was too expensive for them so the vehicle was scrapped. I wish I had known they were going to scrape it. It had always been garaged so it had no rust, it was a sad time indeed.

Comment Re:Misnomer (Score 1) 392

Volvo should anticipate that the driver did not pay for a feature and then attempted to use the feature? The 'feature' in this case requires a whole DIFFERENT system with radar, a front camera, dashboard changes, and software changes... They should anticipate this and, well, do what exactly? You are not entirely to blame. The story and the summary are both wrong. They are not misleading, they are outright wrong.

Comment Every language has its gotchas (Score 2) 336

And it's important for new programmers to learn them - more important than learning syntax.

  For C++ for example I'd warn about classes containing pointer member variables with implicitly-defined assignment operators / copy constructors. You have Foo a and Foo b, where Foobar has a member variable "int* bar". So the newbie does "a.bar = new int[100];" then later "b = a;" then later b goes out of scope, then they try to use a.bar and the program crashes. Seems to be a very common C++ newbie mistake. Eventually they learn to see pointers in class definitions as having big "DANGER" signs over them calling their attention, and/or rely on smart pointers.

Any others that people can think of that are common?

Oh, here's one more: iterator invalidation. A newbie who's not warned about this in advance will likely get bitten by it several times before the point gets driven into their head: "if you're using a class to manage memory for you, it's going to manage memory for you, including moving things around as needed."

Comment Re:Defective (Score 1) 392

Pedestrian detection is a whole other system that requires a front end camera, dashboard alterations, AND an expensive radar mounted under the front bumper. You believe, thus it must be true, that they are ethically mandated to include this several thousand dollar extra (and entirely different) system for free? You believe that the buyer should not be able to opt out of that additional, extra, expensive option and should be forced to purchase it if they only want the parking system which is just sonic and a rear facing camera?

Comment Re:I am amazed (Score 2) 248

Yep, they have been UTF-16 for a long time. And Unicode has been widely broken for a long time. It's not a coincidence.

Someone on StackExchange did some tests last year, adding in 4-byte unicode characters in common applications and seeing how they behaved. The results were really bad:

Opera has problem with editing them (delete required 2 presses on backspace)
        Notepad can't deal with them correctly (delete required 2 presses on backspace)
        File names editing in Window dialogs in broken (delete required 2 presses on backspace)
        All QT3 applications can't deal with them - show two empty squares instead of one symbol.
        Python encodes such characters incorrectly when used directly u'X'!=unicode('X','utf-16') on some platforms when X in character outside of BMP.
        Python 2.5 unicodedata fails to get properties on such characters when python compiled with UTF-16 Unicode strings.
        StackOverflow seems to remove these characters from the text if edited directly in as Unicode characters (these characters are shown using HTML Unicode escapes).
        WinForms TextBox may generate invalid string when limited with MaxLength.

I've had more than my share of these sort of experiences too.

UTF-16 is dangerous, and should be phased out as much as possible. Where absolutely needed for performance reasons, it should be an internal representation only, hidden from the developer as much as possible. In particular, "length" functions should return the actual string length in characters, not code units; indexing functions should take character offsets; not code unit offsets; and returned "single characters" exposed to the developer should be of a format capable of handling multi-code-unit glyphs. Anything involving working with actual singular UTF-16 code units should only be available as a "for advanced users only, use at your own risk" functionality.

Comment Re:I don't get it... (Score 1) 392

You will need more than a couple of friends to move a 7 series BMW or an S class Mercedes. I have a factory restored 95 740IL that I drive for fun during the summer some times (I have an M3 that is much newer) and while it is plenty powerful it is also like driving a truck as far as weight goes. Hell, I think the GVW on the 740 is higher than the GVW of my old F-250 that I use to plow my driveway.

Comment Re:Terraforming potential? (Score 1) 278

. So basically you'd need to impart almost 6x as much energy (36x as much speed) to get to Mars as to just escape Venus

Yes, the velocity would need to be tens of kilometers per second. But really, what's the limiting factor here? Certainly not skin drag, when you're talking something on the necessary scale here. Viscosity losses, radiating the energy away to space as heat? The energy can't effectively radiate away as heat, that's why the funnel is there, to reflect IR while transmitting visible light from the sun. There's not many options for the gas to lose energy except to accelerate.

Basically that "negligible drag" would be the only thing providing a supporting force to the funnel.

Negligible from a systems perspective. But from the perspective of the funnel, it's tremendous force. The mass of the funnel is insignificant compared to the mass of the rising gas when you're talking about a megastructure.

I wonder though what might happen if you directed the CO2 to Venus's L4 or L5 points? Could you build up sufficient mass to create a stable bubble of CO2

That would be.... unusual. What would you call that, a "Gas Dwarf"? I really have no clue how much you could have persist stably there, but I'd be really curious to know. It'd be particularly strange if you could make it out of a combination of gasses that are breathable - aka, limiting the CO2 levels, O2 from CO2, and any mix of Venusian/Jovian N2, Ar, and He as buffer gasses as needed. If the water vapor levels were low then there would be little in terms of cloud cover to reflect light. Earth's atmosphere absorbs about 1/3rd of the sun's energy, so with two passes through it'd absorb about half; at Venus's distance it'd probably be a pretty comfortable temperature. Gravity would be tiny. Obviously not long-term stable due to the solar wind, and high radiation, unless you artificially create a miniature magnetosphere. But in the short term...?

That would be so weird to be floating "midair" in a temperate breathable environment with no land anywhere.

Comment Re:Hobbit (Score 1) 278

Well, certainly more realistic than living on the surface. And probably easier to set up than a Mars habitat - terrain is irrelevant and your entry is so much easier - plus, even normal Earth air is a lifting gas on Venus. And it'd be no less self-sustaining (that is, to say, "not very" ;) ).

There's no need to send people offworld to do science, whether to Venus or Mars. But while there's no need for any kind of "facility" at all, manned or otherwise, for robotic equipment on Mars, the concept of some sort of floating "facility" on Venus is pretty important. Any sort of craft designed to tolerate Venus's surface environment is going to make a terrible analysis lab or sample return vehicle. I mean, even solar panels would have to be heavily shielded on a sampling run to not be destroyed; there's very little that you can have exposed that can tolerate that environment. Sampling and analysis or return on Venus is best done in two stages: 1) Buoyant craft that repeatedly dive and rise the atmosphere like submarines and take samples on the surface, and 2) a floating platform containing any analysis equipment or return hardware, high gain communication with Earth, and solar panels to recharge the batteries of the sampling craft while samples are being offloaded.

Venus's surface is really unusual and it'd be neat to know more about what's there. I'm still not big on the concept that we need humans there to do it, but at least a floating platform of some kind would be important. The only advantages I could see for having humans would be to cut the communications latency with the samplers to allow for smarter sampling decisions without requiring them to wait in the harsh environment for round-trip communications on Earth, the ability to repair samplers, and perhaps mildly better local analysis of samples and/or decisions about what to bring back. Hard to justify the added price tag, though.

Comment Re:Will Technology Disrupt the Song? (Score 1) 158

That may be a structure for a verse, but entire songs often have a similar structure: verse-refrain-verse-refrain-BRIDGE-refrain, where each "verse-refrain" unit is kind of like a big "A," the bridge introduces contrast, and then the final return to the refrain (often transformed or at a higher energy level) provides a satisfying conclusion.

That is a fantastic post, it deserves a +5. The only thing(s) I would add or change is that the Bridge may lead to a solo (or solos if live, for example). I would also share, as you seem interested and knowledgeable, that if you are a guitarist then instead of AABA change the A to Amin and the B to a B7-Dim9th. I may have screwed up the latter but I am pretty sure it is correct.

Comment Re:Will Technology Disrupt the Song? (Score 1) 158

I gave them two tries, Further Fest and a concert at Great Woods... Anyhow, as much as I love their music, the Black Crows are not a band to see live. I had a sibling that I warned who did not believe me and paid way too much for a couple of tickets. He too had the same experience I had. (They headlined at Further and while I was looking forward to them I did not attend to listen to them specifically. I was more interested in the remainder of the Grateful Dead - specifically Mickey Hart and the Planet Drum. I was also greatly interested in the acid.) Surprisingly good? Meatloaf. An old band still rocking it out live on stage (they are all like 70+ now) is Three Dog Night. I found the latter more amazing than the first but the first was pretty surprising. I had only gone to see Meatloaf because I figured I had never seen them live and that I must do so when they were only a two and a half hour drive away and I had nothing better to do.

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