Please excuse me if this sounds pedantic but it is relevant for the subject.

When we're talking about levels of -51, -91, -113, etc., these are probably GSM signal levels, and the unit should be dBm.

dB alone is just a ratio, which is suitable for indicating for example Ec/Io, which is sort of signal to noise ratio when in WCDMA mode (the iPhone, being an UMTS phone can use GSM or WCDMA). -113, -51 do not look like Ec/Io values (these are good around -10dB).

When in WCDMA mode, Ec/Io is much more relevant than signal level and I believe phones show bars proportional to that. When in GSM mode, signal level is more relevant, and phones show bars proportional to that.

In WCDMA mode, the level is much less important than the phone capacity of extracting meaning out of the noise. You may have a very low signal level, but if the Ec/Io is good, you can place a call. You may have a high signal level, and not be able to place a call if your Ec/Io is poor. This is also true (but not as critical) for GSM mode.

A conclusive test or comparison should not be based only on signal levels, but use a proper GSM/WCDMA phone test equipment, capable of generating different signal levels (GSM) and Ec/Io (WCDMA), then collecting the phone's received Bit Error Rate, or Frame Error Rate. Believing in the level information the phone itself informs and relating that to dropped calls is quite subjective, as it is not a controlled environment, and what the phone informs may be wrong.

In the analog times (AMPS), signal level was all you could measure, and interference just meant the sound would be crappy (and the occasional undesired "group call"). If there was a good signal level, you could place the call (but the quality could be awful, there was no way of knowing).

With digital, bit error rate is what matters, and signal quality is more important than signal level. As long as the received signal level is above the phone's sensitivity (and here is a place where you separate manufacturers who know their RF from the ones who don't), then that's "level enough". It doesn't help to have a lot of signal strength (power) if due to the signal quality (signal/noise) or your hardware/software quality you cannot pull the useful data from it.

In the digital age, it's not the size of your signal which matters, but what you manage to do with it.

Good point, but just to add some more information, here are my two cents:

When an UMTS phone (like the iPhone) is in GSM (and GPRS and EDGE) modes, the signal to noise could be measured by comparing what the receiver gets during its receive timeslot (GSM/GPRS/EDGE use Time Division Multiplex Access - TDMA) against what it gets out of its receiving timeslot. Nevertheless, this is not how the phones measure the signal quality or signal to noise, which as you pointed out is more important.

What is actually considered as a measure of signal quality in GSM is called RxQual (receive quality), which is derived from actual Bit Error Rates (this is part of the GSM/UMTS standard; there is a table relating RxQual to BER in GSM 05.08). The phone reports RxLev (level) and RxQual back to the network for the network to decide about changing the serving cell site (handover). The phone bars however (as far as I know) show something logarithmically related to signal level. This may be not a good indication if you have a LOT of signal, but it's all interference (good RxLev, bad RxQual).

When a UMTS phone is in WCDMA mode, then signal to noise is even more important, but it is measured by the phone by comparing the level it pulls out of the "noise" when using the correct scrambling code against the total received level. Remember that WCDMA uses codes to separate each data "stream", all mixed in the same wideband frequency channel. The more codes in use, the more "noise" you see out of your own code. This measurement is generally called Ec/Io (UMTS standard 3GPP TS 25.133), and is also reported back to the network, with other information, for handover decisions.

I *think* that when in WCDMA mode the phone bars are related to Ec/Io, not actual signal level. If not, they should, as receiving a lot of signal "power" in your antenna when in WCDMA mode does not mean you can get/maintain calls. In GSM mode the "noise" is interference in the GSM frequency, generally coming from (poor) network design allowing channel reuse in cellsites that can "reach" the same spot. In WCDMA, a lot of "noise" comes from normal network usage, so it's a fact of life. Have you heard that CDMA/WCDMA cell coverage "shrinks" with traffic? This is why. You may have good WCDMA/CDMA quality off peak usage hours but "no coverage" at the same spot during peak hours.

All these measurements are ready to use in the phone's UMTS chipset, as they are mandatory by the standards (which by the way are freely downloadable from 3gpp.org), and the standard is strict about how they are measured/calculated - phones have to do it right to pass compliance tests.

Apple (intentionally or not) may have converted them wrong to the bar display (maybe they did not figure out the logarithms right, being newbies in the RF world...), but the measurements could not be wrong, or the phone shouldn't have passed conformity tests.

and UMTS uses WCDMA.

What we are used to call UMTS is GSM + WCDMA (the standard can go farther, but the bread-and-butter is GSM + WCDMA now).

GSM uses TDMA (which is not the "old" TDMA, which technically is called IS-136, and IS-54 when it was part AMPS, part TDMA).

The WCDMA used by UMTS (when your phone is in "3G" or "3.5G") isn't your grandpa's CDMA either, which technically was CDMA2000, and IS-95 before it).

I specifically said WCDMA because it is a characteristic of WCDMA (and CDMA) to be much more sensitive to uplink power control than GSM when it comes to degrading overall network performance - when your UMTS phone in (W)CDMA mode transmits with more power than it needs to, that is "noise" for everyone else's phone signal in the same (W)CDMA carrier trying to reach the cellsite.

That effect is not as relevant when your UMTS phone is in GSM mode, because you are not sharing the same frequency (at the same time) with others near you. In (W)CDMA, many phones share the same frequency at the same time, each one being separated by a XORed code, crudely speaking (black magic involved).

If your phone in GSM transmits with more power than it should, you just get worse battery life (and a remote possibility of interfering with someone using anoter cellsite far away).

If your phone (or a lot of phones) in WCDMA transmits with more power than it should, it hurts network capacity.

That sounds strange. Only while in idle mode (no calls in place) a GSM/UMTS phone has some autonomy to select the cell site to which it will "listen" to.

If the iPhone follows the UMTS standards, while in a call it reports received signal information from neighboring cell sites (or towers) to the network, and the network then decides which cell site(s) the phone will use (or switch to, what is called handoff). The phone has to obey the network's decision, so the only way that the phone software could affect the cell site choices would be to send "fake" (or wrong) received signal information back to the network (which would violate the GSM/UMTS standard).

...so when the call quality gets bad, you'll be able to blame the network, not Apple.

...and on the transmit side, the software will pump up more average power than what the network power control requests, so your battery life will get worse, and overall network (WCDMA) performance will be degraded for all users in the neighborhood.

Also consider the possibility that this could get you in trouble in a math/physics exam. I thought I'd never go back to a classroom, but was pushed into a post-grad course - and was prohibited to use my old faithful HP49G on the financial/accounting exams "because it is alphanumeric and can be used for cheating"! I had to borrow a 30 year old 12c, but you won't be able to borrow a clean pair of arms.

Very interesting. Like the underlining rules that form different fractals, these political/social differences shape different maps.

There could then be at least three "drives" competing to shape the grid: "uniformity" (theoretical ideal mold global solution, unaware of traffic needs), "traffic shaped" (overall, prioritize the majority, screw the few who needs odd itineraries), "incremental" (each line is negotiated as an isolated problem/cost, overall final result may be unoptimized) - besides the obvious "economic/geographical" (how much it costs/is it possible to go through or around a mountain/lake).

I'd expect the same to happen in other systems where location and capacity planning are necessary: roads, schools/hospitals, telco backbones, cellular phone base stations, etc.

We are complex molds, but one could tell the kinds apart by looking at the drawings we make in the petri dish.

Somehow the two maps you mentioned fit the expected, one showing a more cooperative/harmonious society, and the other a more individualist one!

I assume the mold paths solution simply "converged" to the most efficient way of carrying the nutrients between the nodes. As it was mentioned here, soap bubbles will also "find" the shortest paths, as will the mold's "brute force" approach (broad spread, then coalesce to the most efficient ones).

But the natural solutions would not take into account the human distribution and convenience, as each node (apart from the big central oat flake) have the same appeal to the mold - and possibly the ones closest to the borders have less appeal (or more "cost"). Same goes for the surface tension solution (soap).

What if the human factor shifts the "weight" of some nodes and paths? For example, there might be very few people needing to go from node A to B, but many needing to go from A to C, so although a "natural" solution would only take the distances and positions into account, a "human" solution would want to favor the trip from A to C even if that meant making the A-B trip worse.

So if the mold solution is really very similar to the real rail system, then either Japanese commuters are amazingly "natural" in regards to where they live, where they work, and demographic distribution, or the Japanese railroad engineers missed the human factor when designing the grid. The first possibility is somehow beautiful and creepy at the same time.

"in case you decide to vote or get a public job"

that's not the whole trouble,

1 - you cannot even apply for a public job selection exam
2 - you do not receive your salary for the 2nd month after the election if you have a public or somehow government-related job
3 - if you represent your own business, you cannot participate in government bids
4 - you cannot renew or get a passport or ID document
5 - you cannot renew your registration to go on studying for free on public schools
6 - you cannot get loans from financial entities ran by the government

(4) is already a lot of trouble to me, as although my job is not government-related (we do sell for the army, but I do not represent the company legally), I really need my passport to be able to work.

And as I pointed out, you CAN justify your absence, which is even easier than to pay the fine at the electoral justice. The law says you OUGHT to vote, and there is a lot of trouble if you don't. But yes, you can justify the absence or pay the fine (I didn't know it was so cheap though!).

Either voting, justifying, or paying the fine, there's accountability, or you get in trouble.

The point is that the electoral justice knows with some precision how many (and from where) votes are expected, which makes frauds a bit harder - at least one tiny advantage of the (otherwise stupid) obligatory voting over methods which allow dead people, outsiders, and Disney characters to register and vote.

- You OUGHT to vote if you are a Brazilian citizen between 18 and 70, and is not illiterate. You get in a lot of trouble if you don't.
- You don't register for avery election; you have a "voting ID" valid for every public election.
- You have to vote in a specific designated place (noted in your "voting ID"), generally the closest voting section from the address you provided when getting your "voting ID". If you are away, you have to justify the absence (preferably on a mail office, at the election day)
- Election happens in one day, throughout the country (there may be 2-phase elections, for example for mayor, governor or president, when in the 1st phase the winner does not get more than 50% of the votes - oh, yes, we DIRECTLY vote for president - every citizen's vote has the same "weight").
- Although the voting machine is electronic, when you get to the voting section there are PAPER books with all voters for that section listed, and your ID is checked against that. You sign the book and get a "receipt" detached from it (you have to prove you voted, as it is a legal obligation).

Soo, the electoral authority "knows" how many votes should appear in the results. Generally we do not have Disney characters, dead people, etc. voting, nor people voting in several electoral sections.

As far as I can remember, results have matched the pre-election polls (from multiple sources) quite well. Generally people know in advance what the result will be from each city or even city area, and that can be seen in real time as the electronic counting unfolds at election night (yes, we generally get most results in the night of the election day). I can't recall results being seriously contested by the losing parties (we have MANY parties).

Results are manipulated by "social engineering": Sending buses/boats to collect people from remote locations for voting in "exchange" for voting, trading dental treatment promises, money, death threats, etc. Illegal too, but easier and more difficult to trace than manipulating after the votes were cast.

I trust that there are so many crooks in politics in my country that if a party found a way to manipulate the results after elections, there would be so many me-too-or-else-I'll-tell that it would spread like a wildfire and the results would be awkward enough to be laughable. It is a self-regulating system. If a hacker found a way to manipulate the results, he would not stop at selling the method to one single candidate. I believe the same applies for other voting methods (except the ones which allow Mickey Mouse to register, of course) - it is not the system itself that prevents fraud, but the fact that fraud works both ways, and that the result is not a complete surprise.

In recent international elections you can see in the news that if the results do not match what the population though it would be, it is noticed at once, and people get to the streets (sometimes there wasn't even a fraud, it's just that some people won't accept the losing). It hasn't happened here so far, so we still trust the way it's been done.

You're right. We have a very real non-fossil, non-nuclear fuel solution, environmentally friendlier than fossil.

We have been running cars on sugar cane ethanol in Brazil since the 70'. The technology is very mature already, and most (if not all) cars made in Brazil now are "flex-fuel" (can run on any mixture from pure ethanol to our gasoline, which actually already has 24% of ethanol).

It always annoys me how few people have heard about this outside Brazil, and how the (american) media tries to create every possible bad news/stats/study about it.

I had to send some furious emails to Road&Track because everytime they mentioned "ethanol" as fuel they'd list disadvantages associated only with corn ethanol, as if it was general to any ethanol source, never mentioning the existence of our established system here. Only recentlyI could I finally see "corn ethanol" correctly identified in the magazine when identifying a disadvantage.

It looks to me the media likes to bash ethanol fuel and ignore the Brazilian success with sugar cane ethanol because: 1 - They are against the corn subsides, 2 - They don't want it to look as a good idea until the US can produce its own ethanol (I don't think we could handle the US demand for ethanol anyway), and 3 - "not made here"

(so please, before posting gossip about "sugar cane ethanol harming food production", "sugar cane ethanol causing rain forest damage", "ethanol fuel bad for environment", do check your sources for hidden agendas)

I won't debate about this, so some points in advance:

- CO2 emissions at the exhaust pipe are no better than fossil (maybe worse, since you burn about 30% more fuel in volume per km), but most of that "C" was arrested from CO2 in the air when the sugar cane was growing.

- unlike corn ethanol, the complete cycle (from production to engine) returns 4 to 5 times more energy than it was "invested" in production, so only a small amount of CO2 is produced by other energy sources (specially considering that most electricity in Brazil comes from hydroelectric). The rest is "solar power" - the only real renewable source, as it is the only significant energy being "added" to the Earth all the time.

- along the years while ethanol production grew in Brazil, food production also grew. We're not stopping producing food to produce ethanol. Food production is (as everywhere capitalist else) regulated by market price. Nobody will produce food if it costs more to do it than what you can sell it for.

- Road&Track (Dennis Simanaitis) once mentioned a paper where it said the rain forest was being cut due to ethanol production. First, the rain forest region is not good for sugar cane. Second, when I found&read the paper, it actually suggested that corn ethanol subsides made many US farmers drop soy production for corn, that made the soy international value rise, some Brazilian farmers could have expanded soy plantations in the rain forest region (I have not verified this fact, but one can see how far the prejudice can go).

- ethanol production got to a point where we have big sugar cane plantations close to the ethanol production (thus reducing the need for fossil diesel for trucks to carry the cane to the plant), the vegetal matter not converted in alcohol is burned to provide heat for the conversion process, and in at least one case excess heat is used by a power plant which supplies electricity for the site and nearby community (again, the CO2 produced by this burning is "renewable")

It is not cold-fusion perfect, but it is a way better, not pie-in-the-sky, alternative for fossil fuels, real, tested, mature, and in use for some 30 years.

(even cold fusion worries me a bit. what are we going to do with all the He produced when/if all energy we use comes from cold fusion? will we all talk funny? or will it take the ozone layer's place in high atmosphere?)

You seem to think all things must have only one cause/solution/explanation, and that must be the one you believe. "Oh, you see: There IS another explanation for this, so you your's is futile, impossible and completely insignificant". I tend to think most of the "non-digital" things may have composed causes, and I like speculating about it with people who know how to do it friendly, so it is useless to keep arguing, specially since I just noticed your sig, and I don't believe in you ;-)

Knowing that the police may quickly verify the identity of someone who claims to be someone else really gives me the illusion of feeling safer. I don't know why.

Giving an easy way for the police to confirm that I am myself only gives the government more power if I DON'T want them to know who I am.

I'm not trolling or antagonizing with you, really. I just don't get it (maybe I was brainwashed, being born during Brazilian's military dictatorship).

Case 1: I have the right not to show ID, police asks me who I am, I tell them the truth, they go away.
Case 2: I have no right to deny showing the ID, police asks me to show it, I do, they go away.

They got the true in both cases. They'd only get a lie in Case 1 if I had a reason to hide who I am.

How Case 2 gives them more power over me than Case 1? By the same logic, one will get to the point where police won't be allowed to even get close to you and ask for the time without having reasonable reason, a warrant, and five lawyers in standby.

In Brazil the law says you have to show ID if asked for, but that not result in Police asking for IDs of every person they meet (as I said, I was never asked for it unless while driving). It just makes things easier when they do have to verify your identity.

Even if the law did not say I had to show it, why deny it just because I have the right to? The law doesn't say I have to pack broken glasses safely when disposing them in the recycling bin, nor where and how I should leave the tray in a fast food, but doing that makes other people's jobs easier. Showing the ID to an officer (even if you don't have to) makes his job easier. Isn't that a good thing?

There are bad cops? Sure. But what extra "abuse" rights does that rule gives them? If they are going to harass a guy just because of his looks, they are going to harass him - the only difference would be that he would legally have the right not to show the ID - not before "his" stash of pot was "found".

In the US, if you deny showing your ID, the cop will not know if you are doing that because you "know your rights and draw the line", or if you have a serious reason to hide it. In Brazil if you deny it, you must have a serious reason, so there's no doubt.

To be honest, there are indeed downsides: You always have to remember carrying your ID, and if you are caught without it by a commonsenseless cop you'll be in trouble, but it is the same if you are caught driving without a driver's or vehicle document - or, in the US if you are thrown in a situation where you really have to show ID. Basically, everybody carries it - and in regions so underdeveloped that people do not have them, well, generally there aren't even cops there, and if there are, they will know people don't have IDs.

I used "positive feedback" in the "control loop" sense, not in the "pat in the back" or "antropomorphic" sense.

You introduce a tiny, random perturbation in a control system. Positive feedback loops back to the input reinforcing that tiny perturbation in the same direction. Negative feedback subtracts from that perturbation in the input.

And please, positive/negative are not something intelligently designed, it's just positive=pass the characteristic along; negative=does not pass the characteristic along. Huge male sea elephants are a result of the "positive feedback" of females picking the bullies over generations. In the same "control loop" terminology, one could say the output "overshoot", and now the size may become a disadvantage (they may unintentionally squash the females) - that's "negative feedback" kicking in.

Hmm, I did not anthropomorphize evolution. It was a metaphor. Do you think incest is just a taboo? Isn't there a biological advantage in not interbreeding? When there's a possibly inheritable characteristic (not "designed"!) that has some slight advantage over another in terms of health/survival of the genes, won't that result in this characteristic being reinforced because of natural selection? Can then you "get" the metaphor of, say, "The urge for a cockroach to run to dark places is evolution's reaction to predators" without one having to explain the actual whole process? (well, my mistake for using metaphors in writing a scientific paper...)

But you must be right; incest is just a taboo - Nature almighty does not want us to mix up genes; that's why She created Eve from an Adam's body part; we all have the same genetic code, and that's the way it should be.

As you said "many animals have incestuous relations **when there's no better alternative**". How do they "decide" that not interbreeding is the "better alternative"? Do animals have taboos too? Or is that a behavior that could be explained by the advantage of not interbreeding being reinforced by natural selection?

(and yes, I know there are even animals that reproduce asexually, thus passing along the same code. I'm talking about the rest of us)