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Comment Re:Saftey & Planning (Score 1) 55

An experienced glider pilot has one more vairometer to use - his own posterior. One can feel speed changes in it :)

Nope. As you say it, own own posterior is an accelerometer, measuring the speed changes, NOT a variiometer, measuring the speed i.e. the position change. You're one derivative wrong.

Right, one cannot integrate it in head for more than a second or few. I wanted to express it is good enough to detect where turbulent air region starts. And from the safety point of view, if you have enough height then it does not matter much whether you are raising or falling. The ground is still far away to have time to correct it before crashing. And near the ground you can even see it. It is important to know the speed so that one does not stall or cross Vne. But even if speed dial would break in some very unfortunate event ... it is not all lost since near stall the plane starts to shake and the aerodynamic noise changes quite a bit with raising speed. So just keeping the plane in a comfortable noise level will make sure you are not going to cross Vne. Well this is true at least in low altitudes. May be in very thin air the aerodynamic noise is different enough to cause trouble. But I'm not trying to indicate one should fly without instruments.

Comment Re:Saftey & Planning (Score 2) 55

An experienced glider pilot has one more vairometer to use - his own posterior. One can feel speed changes in it :) Also one does not see how air moves, the pilot can feel whether the plane is nearing the turbulent region. This together with general knowledge about thermal ans waves helps a great deal.

No idea why Bigelow screwed up. Gliders are built for turbulent weather. When one is targeting thermals then it is the turbulent parts of the atmosphere the plane is heading to. Stall speed is typically about 40 knots and Vne (top speed) is about 120 knots at low altitudes. The range is quite big. And it is not a big deal to get below the stall speed if you have enough height. You just lose part of that height. I experienced stall in a glider myself a few times. Not a big deal. On the other side crossing your Vne is almost as good as trying to kill yourself real hard. It is not easy to fly when your wings break off :) Whatever Bigelow did, he should try not to cross his Vne. Crossing Vne was probably a consequence of something else though.

Comment Re:Saftey & Planning (Score 4, Informative) 55

They do not want to catch a raising column of hot air (thermal). They want to catch a wave downwind of a mountain. The waves reach considerably higher than the mountain which generates them. Thermals are typically very bumpy. Waves are typically extremely steady. Only their middle part (the rotor) is bumpy but you can avoid that. This should be quite a steady flight.

Comment Re:Family member's WIN computer got locked out (Score 1) 581

Windows is becoming less and less relevant for gaming. Most people game on smartphones/tablets or consoles and SteamOS is gaining more support by the day.

As for as the number of players you are probably right. But most gaming revenue is still on PC:

But the trend indicates the mobile platforms will eventually prevail.

Comment Re:"Open == Secure"? (Score 1) 214

Closed source, commercial software is written by people who are paid to do it. Software that people are paid to written more often includes the boring, not-fun parts like testing, documentation, and auditing. Therefore closed source software has a higher chance of being audited.

Why do you think a car company would not audit open source software it is using in their cars? They can get publicly ridiculed for low quality of their code. Would you buy a car from a company which was shown to have crappy and insecure code in their cars? This is not like a PC which you can reboot and all is fine. And why do you think a company which does not audit its open source code would audit its closed source code?

We're both just constructing arguments that may or may not be true. My point is that those arguments are irrelevant. A given piece of software either has or has not been audited.

I agree with you. My point is that in the case of a car software the openness of the source code would give the company even more incentives to audit it yourself compared to a closed source code. And moreover there are people who are really interested in cars and which would definitely look at the code. What about all the rodhoders?

I mean you want to move experience from simple PC software to car software. I do not think this is valid.

Comment Re:"Open == Secure"? (Score 1) 214

They're both wrong.

Open == You can audit it if you want. It's absolutely no guarantee that anyone ever has.

There may not be a guarantee but there is a good change it is statistically true. There exists a group of people who may want to audit a car software and they can do it only when it is open. Therefore open source software should have a higher chance of being audited.

Comment Re:Given the hype around 3D printing ... (Score 2) 101

I just don't find enough uses for it to justify the floor or bench space for the machine. In subtractive manufacturing where one takes away material I can work in metal, plastic, and wood. I can cut, plane, sand, shave, drill, tap, or die-cut, and if I pick up one of those tabletop mills, I could mill and otherwise create channels, and these can all be done in three different materials.

The problem is that a cheap 3dPrinter can do shapes which would require 5-DOF CNC. These are very expensive. So you can use only plastic in a 3d printer but you can do very complicated shapes. With a cheaper 3 DOF CNC you can use also wood or metals, but the shapes you can produce will be simpler.

Comment Re:Wow! (Score 1) 99

Don't forget it isn't just raw watt savings. You also have the heat dissipation of that heat, and then the additional AC load and it's inefficiency. I'd multiply power savings by 3-4 if you want an accurate figure for amount saved.

Fans running at a bit higher RPM does not increase energy consumption in a noticeable way. A typical PC fan power consumption is about 2W. If you are water cooling without fans then there will not be any difference at all.

If you need air-condition at all then you must realize that these systems have COP of about 4. That means that increasing heat dissipation of your computer by X watts will lead to increase of air-condition consumption by about X/4. That means that your power multiplier of 3-4 is very wrong. If you really want to apply it at all (notice that in during winter you save on heating) then it should be somewhere around 1.25 - 1.3. That does not make a significant difference.

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