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Comment Re:Not sure how this is necessary (Score 0) 323

The TOS of Facebook are not legally binding except (perhaps?) in the USA. They contradict any copyright law un any nation that signed the 'Bern Convention' (which is actually signed by the USA, too.

Regarding the password issue ... in what delusioned world do you live?

Constitution > law > TOS. Yes, in the USA you can craft _valid_ contracts, that are against the law. So the 'equation' above is not perfectly right. However, TOSs usually do not define a legal binding contract, not even in the USA.

If you want to give law advices, I suggest to read the laws. They are usually ad clear as programming code and not that hard to understand.

Alas, the USA have not that much written law ...

Coming back to your last sentence: law enforcement has any legal ground above the TOS of a company.

Comment Re:Design failure (Score 1) 130

The stirling engine needs to survive that temperature (the one of the heat source). That is the main problem.
In respect to a stirling engine, and the needed wattage we talk about two things: the engine and the generator. (After all the engine has to move the generator to produce the electric power).
Then we have to check how much heat we can radiate.
Because the temperature of the radiator will be the 'low temperature' of the Carnot efficiency calculation.

I mean: generating electric power and designing a system based that 'works' is the easy part. A getting it sized to fit into a space craft comes next. Efficiency is the result of the first two steps, and actually it is just a number for geeks.

Who cares if device A costs so much money and space and weight and has an efficiency of X when device B is bottom line cheaper, fulfills the requirements (creating electric power for so long with so many watts) but is 'less efficient'?

I guess you have a point that stirling engines are still very underrated regarding niche situations for power generation.

Comment Re: a better question (Score 1) 592

Ofc QNX ;)
That is what I wanted to point out, the parent was a bit delusioned.
What OS you can use for 'process control' basically only depends on your real time requirements.
If it is ok that your control loop needs 10 seconds to react on a change on input parameters, then you can use anything that guarantees you that you meet that 10 seconds limit.
Example: a pump pumping 500 litters per minute out of a huge reservoir. At some point a swimming signal giving device says 'stop'. Reacting on that - depending on the size of the reservoir - will have basically a non measurable influence on the hight (depth) of the level in that reservoir, regardless if the reaction is happening in 1, 10, 50 or 100 seconds.

My oldest Mac from 1990, running with 1MHz on an 68000 will do that just fine. Hm, I guess that one runs on 2MHz, not sure ... it got an very fast 68030 card extension at some point.

Comment Re:call me skeptical (Score 1) 360

Thanx for the info :)

Obviously you don't understand what you post ... but that is normal on /.

The error bar you see has no implication in regard of the fact that 2014 is:
A) the hottest year ever recorded
B) is regardless how you see it amoung the 10 hottest years ever recorded

Well, that means ofc. the 'recordings' done in the last century or so ...

Hm, regarding your juggling with error bars I suggest to take a class on statistics or something. So you don't have to use your layman interpretation on that subject, which obviously contradicts the scientists interpretation who declared 2014 to be the warmest year recorded ;) (sorry, just a hint ... my english and my math in english is to bad to explain your fault to you with my words, so I try to be funny, but likely failed there, too)

Comment Re:Problems in C++ (Score 1) 386

The first problem is: there is no diamond problem. Everything works as designed. Using virtual inheritance means you have to walk back in old sources and find the first inheritance to the same class and make the virtual, too.
So: no real solution, as such sources usually are not under your control.
And in cases where you indeed want to inherit several times, without using 'virtual' you still have no option to 'access' the 'parts' you intentionally inherited multiple times.

The solution would be so simple:
class Derived : Base A, Base B {} and now you could write Derived::A and Derived::B to access the 'parts' if you needed to. No idea why the designers of C++ are against this solution.

So in our days the internet is full with advices not to use MI in C++, however there are plenty and elegant uses for it.

E.g. you know you have certain objects which you want to hold ALWAYS in at least two linked lists.

An easy way to do that is to have a LinkededList template that has as template argument an integer or an enum.

Now you let inherit your class twice from that List with two different arguments (constants like 'parent=0' and 'siblings=1'). Now every object has a linked list going up to the parent and one covering its siblings 'build in'.

I did not invent that 'idiom', Jiri Soukoup did.

Anyway, in combinations with templates MI is a killer feature. I'm really pissed that Java/C# has neither templates (and no, generics are something completely different) nor MI, just because some idiots spread the mantra "MI is bad" in the early 1990s ...

Comment Re:command line, finder (Score 1) 592

As I told you now 3 or 4 times: you are wrong.
The bash runs exactly the same regardless on what operation system you are using it.
It it is not working for you, .profile or .bashrc or any other config file is messing it up for you.
Bringing up random links which give you a +1 informative rating does not change: that you are wrong.

I use a bash on every system I work on. And: there is no difference at all between my Mac, or the Suns or IBMs machines! And the heck should there? Sorry, you live in a dream world and have some misconceptions about 'how stuff works'.

Comment Re:Problems in C++ (Score 1) 386

That is wrong.
Every class that uses a virtual method has a vtab (and in nearly every scenario where you use inheritance, you should have a virtual destructor).
Virtual inheritance is a a trick to avoid the so called 'diamond problem' if you happen to inherit via different pathes from the smae base class. However it is not the solution :)

Comment Re:Design failure (Score 1) 130

The Carnot efficiency is only helpful if you actually have a device able to harvest that energy.
Otherwise it is just a meaningless number.

Carnots laws simply say the efficiency in an 'heat engine' depends on the temperature difference between the max and the min temperature.

So if you had a turbine made from material that can sustain the max temperatures you mention and is operating in an environment that has the low/min temperatures we see, then the maximum possible efficiency is the number you have.

As we don't have that turbine we are stuck with RTG ... and the efficiency there is very low.

Why you link an article about hypothetical nano technology is bejond me :) But I will read it ... thanx for the link.

Comment Re: a better question (Score 1) 592

Ah, does not really make sense that it is the guest OS amd not the host OS, but thanx for the hint. I ebay one imediatly.
Yes, OS X starts to suck more and more from release to release.
My Mac book air (running 10.8) is unabke to do backups consistently to the time machine. Every few days it claims the back up sparse bundle was already 'in use'.
Regularily the Mail Rules don't work. I mean I het ten mails, which should be moved into a folder, 8 get moved, 2 not. After issuing 'apply all rules' manually the last 2 get moved, too.
There are so many bugs ... Apple software never was so bug ridden. And beifre they fix them, they have a new OS release with new bugs .... pft.
I guess windows is not that bad anymore, but as soon as I'm forced to use Office or more precisely Outlook I have to go to work with an empty stomach, otherwise I would vomit 6 of my 8 work hours.

Comment Re:Unanswered questions (Score 1) 65

There was an article on /. about that technology, but with a missleading title ofc. so we can not really google for it. (something like: new break through in PV makes nearly 100% efficiency possible)

A guy in a university is building such IR PV devices to harvest the heat energy combustion engines are radiating. The efficiency of them was very high, around 80% if I recall correctly.

Comment Re:Problems in C++ (Score 1) 386

pointer per object pointing to the class metadata like for RTTI. That pointer you have anyway, it is the ptr to the vtab. And RTTI is accessed via that vtab, in the same way can be any other meta data.
Also you forget: libraries used for dynamic linking already include all the meta informat, method names etc. they only lack a proper 'standard' API to interpret that meta data.
And that 'knowledge' in those libraries is kept in memory anway, which makes your '1k meta data per class is already to much argument' mood.

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