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Comment It lacks the most important thing for evolution. (Score 2) 149

One of the important things for evolution is cycles.

If you have a primitive lifeform ready-to-evolve, but the food that it uses to grow is too sparse to sustain a growing population, everybody dies. Game over.

If you have a primitive lifeform and the environment is just perfect for these lifeforms, they will explode to a uniform big soup of life, but as everybody lives, there is not really an incentive to evolve. Sure there might be competition, but the genes that are slightly better will not overpower the whole population. They might gain a bigger share than initially, but they will not take over the whole group.

For evolution to happen, the situation needs to be "plentiful" at some points in time, and scarce in others. This is what happens when you have a moon that runs around the planet every 30 days, inducing a tide every 12 hours, causing more and less light during the night in a 30 day cycle, a slightly tilted rotation of the planet. 24hour days, seasons. 11 year solar cycle.

This causes a large sample of individuals to arise during plentiful times. Then when things get really harsh, the better individuals survive and the others die off.

Comment Re:Stop the presses! Incredible news story! (Score 1) 87

Do you think that there is an HP marketing-engineering meeting where the engineers say: we measured the battery lifetime as 3 hours under best-case conditions.... And that at the end of the meeting "ok, we've agreed to market this machine as having 8 hours of battery life"?


What happens is the engineers come into the meeting saying they got 3 hours under real-life conditions. The marketing guys say that the competition got 4 or 5 hours, can't they tweak something. So the engineers tweak something and manage to run a test at 4 or 5 hours. So now the marketing guys know they can pressure the engineers to come up with a better number. So they press on. And finally they get a number that can be rounded to 8 hours.

Comment Re:Only works if the runway revolves (Score 1) 340

That is bullshit.

The idea is that when the wind is blowing from say 280, you take off from 280R, coordinated by the tower like normal, and everybody lands on 280L again coordinated like normal. What does it mean to land on 280L? It means that you land on the point where the runway points at wind direction 280, and the "L" means that you land Left of the center of the circle.

Comment Big companies still get it wrong. (Score 1) 124

Just a couple of weeks ago I asked my colleague if he got an Email I knew he was CC-ed on. "Nope didn't see it".

On inspection we found that the sending company had installed DKIM and SPF and set them to "don't warn, simply refuse the mail".

This was something like paypal or ebay where this came from. Sure, they have big infrastructure which is difficult to get right, but also they should have a big team capable of getting things right.....

it is difficult to get things right. Lots of stuff is being sent automatically from "unattended mailboxes". Any bounces or warnings during the testing phase are going nowhere....

Comment Re:Vault 7 (Score 1) 82

Imagine you have a sixyearold who doesn't want to go to school, so he hides the car keys. This morning he hid the keys in the honey pops box. So you decide to put an alarm on the honey pops. Not the fruitloops next to them, not the sugar bowl, not the fridge! Thousands of other places to hide the item, but you put an alarm on the ONE spot he used this time (And you tell him about the alarm!).

This is very similar to how this "FIX" affects the CIA from "hiding the keys" again.

It is wrong to publish about this issue calling this a "FIX".

A "fix" would pose a significant barrier to entry, or at least close this one issue that would allow entry.

Comment Re:Attack Software (Score 1) 514

Well if you want to be a pendant, it works better if you are correct.

So the 5V on my arduino is a measure of its ESD tolerance? Bullshit!

In datasheets, they specify ESD tolerance as a voltage: A standardized capacitor (with a specified capacity, ESR and possibly ESL) is charged to the indicated voltage and the device is supposed to tolerate the discharge.

But voltage in itself has nothing to do with ESD.

Comment Fundamental problem. (Score 1) 124

There is a fundamental law that batteries have to follow.

The energy that is stored has to be able to come back out. So, if you short the electrodes, all that stored energy may be released in a short amount of time. Unless your energy density is very low (i.e. below usable) that will heat up your battery on short notice. There is not much you can do about that.

Comment The dangers... (Score 2, Insightful) 161

> the close call highlights the dangers of asteroids.

One: Nothing happened. So how dangerous was this? If it HAD hit, maybe several hundred people would've visited hospitals and some windows woudl have had to be replaced.

Two: The danger is teaching people "an asteroid killed the dinosaurs, what if an asteroid kills us?". That is dangerous. A really BIG asteroid killed the dinosaurs. These small ones are nothing to worry about. Let's assume this thing is aiming for earth, but hits randomly somewhere inside the moon's orbit. The earth has a radius of about 6000km, the moon's orbit about 300000km. A ratio of 50, so the chances of hitting earth are 1/2500. The people making a stir about these things are the ones that stand to gain employment from scaring the general public about this.

Comment Crunching the numbers... (Score 1) 117

I have a 24V 10Ah 10C Lithium battery. Sold as multicopter battery. It weighs about a kg. (1200g IIRC, but lets round that to make the math easier).

100A*24V = 2.4kW. That's 8 times worse than the 20kW/kg for the metal scraps battery. As the power density is important for flying things, this would be great for flying.....

As to the energy densigty, I have 24V * 10Ah = 240Wh in about a kg. They have only 20Wh/kg. They are worse than my battery by a factor of 12....

Somthing fishy here.

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