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Comment Re:Transmitter off won't work. (Score 1) 259

On second thought:

As a privacy concern the fact that "the network" knows where you are is a problem.
It does not matter whether the network knows your location to 3m (your phone sends the current GPS location), several tens of meters (your phone reports the strenghts of several towers it "hears"), several hundreds of meters/ a few km (which cell) or several tens of km's (the LA).

Track the LA's of my phone and you'll know when I visited my mom last week. Sure, you'd have to guess that I actually visited my mom and not someone else in that town. But if someone develops an interest in your whereabouts, the LA will already give away lots of information.

There MUST be a timeout on an "inactive" phone. Otherwise phones that are dropped into a toilet would remain ghost-phones in the LA where they dropped (pun intended) off the network.

With the argument that it is expensive for phones to transmit, they will transmit as little as possible already. If the timeout is known to be 1 hour, they will transmit after 55 minutes. (provided the protocol sends and ACK from the tower, otherwise you have to account for the possibility of a lost packet and transmit for example every 25 minutes).

Comment Re:Transmitter off won't work. (Score 2) 259

The cell-phone transmit is "expensive" in that it drains the battery. You can optimize the electronics all you want but if you have to transmit a 1W burst for 0.01 seconds to indicate that you're still there, the energy expense of that burst is fixed and cannot be reduced. This is apparently a trick to reduce the number of transmissions from the phone to the towers so that the battery can last longer. I didn't know that. Thanks for the update!

Comment Transmitter off won't work. (Score 5, Informative) 259

If you want to receive calls or SMSes, you need to leave the phone on and transmitting:

When a call for your number comes in, the incoming call is NOT transmitted nationally. Only in the GSM-cell that you are actually in is the signal transmitted. So, the system has to know in which cell you are to be able to "call" your phone. If you properly turn it off, the phone will tell the GSM network it is going off. So when a call comes in, it will go to voicemail immediately. If you yank the battery, the system will assume you are still in that cell where you last had the phone on, but it will probably time you out if it doesn't hear from your phone for a while. (which happens naturally if for example you drive out of range).

Comment Re:No way! (Score 1) 328

Chess will go this route. No Master of any rank will be allowed to exceed their 'reasonable' ability.

no.... This incident is a wakeup call. People showing such a sudden over-achievement should not play games that have a live broadcast of their moves. Or maybe live broadcasts of moves should be stopped altogether.

What we suspect from this incident is that he cheated. If he cheated, the "live broadcast on the internet" helped. Cut that route off. Consider other routes. e.g. people in the crowd doing a private "live internet broadcast".

So: We now know that advanced technological cheating might be going on. So tournament organizers should take apropriate (better) precautions.

It's a bit like some rat-research in the nineteenthirties. People were teaching rats (or mice?) to go to the right or wrong portal with the cheese behind. Turns out that the rats were a) smelling the cheese. b) hearing the cheese by listening to their feet hitting the floor of the arena. There was a widely ignored article about how the rats cheated, NOT solving the puzzle the humans had set up but going for the cheese anyway. Knowing THAT cheating might be going on and knowing some of the routes that this might be done helps in providing a fair competition.

Comment Re:Simply put.. (Score 1) 328

I am not sure where you got this, but chess is easily solvable in finite time.

Where did YOU get the idea that "finite time" has something to do with NP or not?

There are NP complete problems. They are "known to explode" and other NP complete problems can be transformed into them such that solving one solves the other NP complete problems. Chess is not NP complete: The chess board is finite, which means that it is impossible to transform say a large "traveling salesman" problem onto a chessboard.

NP is nonderterministic Polynomial. Say the traveling salesman problem has to be reformulated a bit. The "easily understood" form says: what's the shortest route. The formal question is: "Can you traverse these cities with less than xxx km?". Once you come up with a route that solves it in xxx km, you can easily check if the condition is satisfied.

A formulation of "the" chess question: "does white win?" is likely not even NP. The NP answer would be: Look if you do these moves, you always win. With games like "tictactoe" you can do that sort of thing.

Looking at it from another point-of-view: Chess is a finite game. The board is finite. So if there is a strategy, it is bounded by the size of the board. Chess can be solved in constant time. The problem is: the constant is quite humongous.

Comment Re:The GPL allows them to charge the $4, as I read (Score 1) 371

The FSF is controlled by a certain person known as RMS, who has certain extremistic views on free software. Any and all closed-source software is evil and must not be touched. Fine. He is entitled to HIS opinion, I'm entitled to mine.

What HE wants to "clarify" about the GPL does not concern me. I have the licence and I get to interpret it (within legal limits) as the text allows. We KNOW that RMS wants to "tighten" the GPL to make it more contagious etc etc. RMS would like it very much that when microsoft the company ran any GPL application on any of their computers, they could be forced to open up their software. That's what he really wants. It's not legally feasable to try this right now, but that would be the end goal for him.

When I write code, it gets licenced under GPL V2. No "or any later version". What if RMS suddenly wants to make GPL V4 say: "An author who has released an application under GPL, is required to put all sourcecode he writes on the internet."

I will provide sourcecode to anbody who has (bought) the binary.

Comment To error or not to error. (Score 2) 536

The fundamental problem is that sometimes an error is an error to the calling program, but sometimes it is not.

For example, when you issue: open "$HOME/.myconfig", the inability to find the file does not mean there is an error. Just that the optional config file is not there. But when you try to open the source file for an operation, the open-error really IS an error.

This duality happens at most levels. A library wrapping "open" will have the same problem. Does the caller consider this a fatal error or not?

Similarly, sometimes errors should result in telling the user and then quitting. But for a gui application it's better to show a graphical message and continue, even if the error is more or less "fatal".....

Comment True! (Score 5, Insightful) 253

Absolutely true!

Evolution works that way: In good times, a big population is generated that has great genetic variety. When bad times come along, the bad genetic variations will be removed from the population.

Suppose for instance that suddenly tomorrow all oaktrees had pollen that is deadly to most humans. The genetic variations builtup over the last 200 years might have provided a (possibly small) percentage of the population that is resistant to the deadly pollen. The result would be that a small group survives and starts working on a new gene-pool.

Yes, genetically we have been living in "good times" the last generations. More and more "slight defects" in the genetic pool are able to survive into mature ages.

A friend is totally colorblind. A genetic disadvantage, you'd say? Nope, his "grayvision" is a LOT better than that of most of us. Apparently he can spot camouflaged army-material from way further away than us normal people. When suddenly THAT becomes a winning trait (i.e. those that don't have it die), his descendants will form a larger part of the population.

This expansion of the gene pool also allows for combinations. Suppose the guy with the super-vision marries the gal with the super hearing?

Comment Re:Invent your own exercises (Score 1) 284

After doing tens of programs with pointers and stuff, the intro-to-computer-programming had a task to turn in a program that used pointers to sort a list of items (using bubble sort).

Compare the items, and when they need swapping, swap them. SImple. Well, somehow, my swapping routine with the pointers always messed up. So instead of swapping the pointers, I swapped the whole records. Kind of against the point of the excercise. But the teaching assitant didn't spot it. It was just a stupid excercise way below the level I was at, at the time, and I faked the result because it was pointless.

(to illustrate the level op programming I was at, a later course, had me starting to do the excercises a few days after they opened the practical side of the course up. When I had turned all the excercises 2 days later in it turned out I was the second one to complete all excercises. Apparenly someone was doing 1 a day while I was doing 3 a day, but he beat me by 20 minutes by starting 3 days earlier......)

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