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Submission + - Sunflowers Use Fibonacci Numbers (

sciencehabit writes: The spiraling shapes in cauliflower, artichoke, and sunflower florets) share a remarkable feature: The numbers of clockwise and counterclockwise spirals are consecutive Fibonacci numbers—the sequence 1, 1, 2, 3, 5, 8, and so on, so that each number is the sum of the last two. What's more, those spirals pack florets as tight as can be, maximizing their ability to gather sunlight for the plant. But how do plants like sunflowers create such perfect floret arrangements, and what does it have to do with Fibonacci numbers? A plant hormone called auxin, which spurs the growth of leaves, flowers, and other plant organs, is the key: Florets grow where auxin flows. Using a mathematical model that describes how auxin and certain proteins interact to transport each other around inside plants, researchers could predict where the hormone would accumulate. Simulations of that model reproduced patterns exactly matching real "Fibonacci spirals" in sunflowers. Based on their results, the researchers suggest that such patterns might be more universal in nature than previously thought.

Comment Re:A legitimate point flagged Flamebait? (Score 1) 193

You know how annoying it is when people try to teach you all about their religious beliefs? You know how you get sick of hearing about Jesus/Allah?

That's exactly how other people feel about you when you start to proselytize with your beliefs. I won't wave my religion in your face and would appreciate if you would extend the same courtesy.


Comment Re:Submit this to the front page (Score 1) 6


The trait of curiosity where people are compelled to figure out the whys and hows of things is rare. It is what makes good engineers and geeks.

It is also the #1 trait I look for when hiring people. I don't really care about degrees, certifications or who you know. Show me you know how to think critically and figure things out on your own and you're top of my list.

Comment Re:File this under (Score 2) 262

My suspicion on the BlackBerry claim is that what was intercepted was regular SMS messages, and not the secure BB PIN messaging.

The latter is what is super secure, because it traverses via the data link to the BES and is essentially opaque to telcos.

While BBs have the PIN messaging capabilities that are super-secure, most people I know just use regular SMS because they don't know any better. And you can't use PIN messaging outside your own BES network.

Comment Re:What is MetaData? (Score 4, Interesting) 337

The software I was working with at the time kept text messages as metadata. However, there was a debate between the FBI (give me everything) and the corporate lawyers of the telco about that. I do not know who won or what the legal standing is today.

My suspicion is that SMS messages are kept as metadata.

Comment Re:Submit this to the front page (Score 1) 6

Thanks, but I'm curious how it gets modded in the discussion and whether or not there are any comments here in the Journal.

I've posted an abbreviated version over at HuffPo, and it has basically been ignored. Nothing new there. Only snark gets faved or commented, but still...

I've watched here on Slashdot for almost a decade now and stories on gov't spying on telecoms gets very little traction. Your average Apple or XBox story gets more comments.

The reality is, most people either don't care or think "they only snoop on the bad guys". It is the whole "I have nothing to hide" fallacy.

It is depressing.


Journal Journal: Lies of Omission 6

This is a duplicate of a post I made in one of the recent topics. I'm copying it here for easier reference as I send it to a couple friends.

* * *

So what exactly is metadata?

Many years ago I was a telecommunications engineer for a large company and worked CALEA. For the uninitiated, that is law-enforcement wiretapping.

Comment What is MetaData? (Score 5, Interesting) 337

So what exactly is metadata?

Many years ago I was a telecommunications engineer for a large company and worked CALEA. For the uninitiated, that is law-enforcement wiretapping.

My job was to make sure CALEA functioned properly on the new cellular network. We tested on an internal, micro-cell network that was isolated from the real world. The end result was to make sure targeted devices sent CDR (call data records, or metadata) and voice to the destination. This was all piped thru IPSec tunnels to the appropriate destination law-enforcement agency.

In the event of a tunnel failure, CDRs were required to buffer but voice was not. Saving voice during an outage required too much storage space, but the text nature of CDRs meant they were small and largely compressible.

Metadata consisted of EVERYTHING THAT WAS NOT VOICE.

To be clear, it included the following:

called number
calling number
time of call
duration of call
keys pressed during call
cell tower registered to
other cell towers in range
gps coordinates
signal strength
imei (cell phone serial number)
and a few other bits of technical information.

Everything above "cell tower registered to" applies to traditional, POTS land line phones. This information seems to be what the disinformation campaign currently going on seems to revolve around. They never mention that there are over 327 MILLION cellular phones in the U.S., which is more than one per person. They never mention the bottom set of metadata.

Capturing all key presses makes sure things like call transfers, three-way calls and the like get captured.

It also grabs things like your voicemail PIN/password, which never seems to get explicitly mentioned.

But the cellular set is more interesting. This data come across in registration and keep-alive packets every few seconds. This is how the network knows you're still active and where to route calls to.

But by keeping all this metadata it allows whomever has it to plot of map of your phone's gross location and movements.

By "gross", I mean the location triangulated from cell tower strength and not GPS coordinates. Towers are triangular in nature and use panel antennas. They know which panel you connect thru and can triangulate your location down to a few meters just by the strength of your signal on a couple different towers.

GPS coordinates are "fine" location. For the most part the numbers sent across are either zeroed out or the last location your phone obtained a fix.

GPS isn't turned on all the time because it sucks batteries down. If you own a phone you know how long it can take to get a fix, so this feature isn't normally used.

HOWEVER, it can be turned on remotely and is a part of the E911 regulations pushed to help find incapacitated victims after 9/11.

[There is a reason the baseband radio chip in your phone has closed, binary-blob firmware -- whether or not the OS itself is FOSS. We wouldn't want the masses to be able to disable remote activation, would we? Or let them start changing frequencies and power levels.]

So, are we comfortable with the government knowing where we, thru our cell phones, are at every moment of the day? Because that is what metadata allows.

Think of what can be learned by applying modern pattern analysis to that data set.

Comment Re:Put it in the switch (Score 1) 401

Putting it in the bulb allows for simpler installation. Insteon allows for powerline and RF connectivity this way and makes just such a bulb.

That is a big advantage if you're renting and can't make wiring changes.

Finally, the LIFX and Hue bulbs allow for different colors, which you can't do with the controller in the switch.

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