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Comment War Secrets in the Ether (Score 2) 102

If you're interested in the German side of world war cryptanalysis, an excellent book is War Secrets in the Ether, by Wilhelm Flicke. The author was a German cryptanalyst during the two world wars, and it was written shortly after the end of the second world war. (It is out of print, so I suggest looking in libraries.)

It has been a decade or more since I read it, so I may have misremembered details, but here are a few points of note:

Pre-war, he'd been analysing Russian radio usage. They had a complicated system where the same station would use different call signs depending who they were talking to. This made their intercepts more chaotic and harder to do traffic analysis on. He and all his colleagues were shifted to the western front with the outbreak of war. When the war with Russia started, in the initial shock their complicated system failed and they fell back on a more standard system. Once they started to get over the initial attack and reorganize, they returned to the complicated system. The German cryptanalysts who were present had no experience with this (the experienced ones having been moved) so they interpreted the chaoticness of the signals as showing the Russians were in complete disarray, when the exact opposite was true.

He thought that the course of Battle of Crete indicated that the allies had broken the German codes at that time. (Which was correct, but he missed that they'd broken most of the German codes for almost the entire war.)

They knew that the allies had very good intelligence, but thought that it was supplied by spies. As a result, he spend the second half of the war on a whack-a-mole mission to shut down spy radio transmitters.

He complained about the multitude of German intelligence agencies and their lack of cooperation due to infighting.

Comment Just sit back and enjoy the show (Score 4, Interesting) 133

I really enjoyed this commentary. An extract:

"Eighteen months ago, after the slap-stick bumbling and embarrassing forelock pulling by New Zealand authorities to their United States counterparts was revealed, I was moved to wonder if Dotcom was in fact a computer virus, slowly infecting our senior politicians and agencies of state, and transforming them into figures of fun.

Whether he is a virus, or a puckish imp, sent by the gods to mock those who would rule over us, Dotcom continues his uncanny facility to bring out the ridiculous in them."

Wherever you stand on his legal issues, business ventures and politics, he is great entertainment.

Comment Re:Bad news for ecologists--new license needed (Score 2) 136

There are plenty of scientists out there who poach free online data sets and mine them for additional findings.

And this is a good thing, despite your word "poach". Analyses which would not have occurred to the original experimenters get done, and we get more science for our money. For many big data projects (e.g. the human genome project, astronomical sky surveys), giving 'poaching' opportunities is the primary purpose of the project.

A former boss of mine once, when reviewing a paper, sent a response which was something like this:

"This paper should absolutely be published. The analysis is completely wrong, but it is a wonderful data set, and somebody will quickly publish a correct analysis once the data is available."

Now I need to stop wasting time on /. and return to my work in hand, which, as it happens, is 'poaching' data from
Ingman, M., H. Kaessmann, S. Paabo, and U. Gyllenstern. 2000.
Mitochondrial genome variation and the origin of modern humans. Nature 408:708--713.

Comment Re:"Back to the launch site"? (Score 1) 73

OK, so I'm officially amazed.

Fuel is cheap when it is sitting in a tank on the ground. Fuel at 100 km altitude and 5km/s speed is a very different story. Fuel which you keep in stage I for 'boost back' is fuel you aren't using to put your payload into orbit, meaning you have lower maximum payload.

Comment Re:"Back to the launch site"? (Score 1) 73

A parachute doesn't solve the problem of your stage being hundreds of km downrange from the launch site. A parachute can help in any of my three proposed scenarios. (I think you'd need to jettison the parachute and drop for a bit before firing the rockets, because I don't think you want to try to land while attached to or entangled in a chute. This is what Curiosity did on Mars.)

Comment "Back to the launch site"? (Score 1) 73

How does this work? The rocket will have gone far down range before the first stage separates.

* First stage reverses direction and comes back. Very fuel expensive, I'd be amazed if they're planning this.
* First stage does one 'orbit' (technically it would still be 'sub-orbital') and returns to launch site from opposite direction. Requires that the stage has sufficient energy, and requires some cross-range maneuvering unless you launch from the equator.
* Summary is incorrect, and stage landing site is not the launch site.

In any case, you really want your landing site to be in the middle of nowhere because some failure modes will result in a high energy impact.

User Journal

Journal Journal: In principio erat Verbum.

Here.

In the beginning was the word. Biblical, John 1:1. The full verse is
"In principio erat Verbum et Verbum erat apud Deum et Deus erat Verbum. "
"In the beginning was the Word, and the Word was with God, and the Word was God."

Comment Re:David Weber (Score 1) 236

I tried a couple of Honor Harringtons but gave up in disgust at the author's political strawmanning.

In those books, a character can't be pacifist without also being cowardly, hypocritical, corrupt and Machiavellian. Only characters who adhere to a particular militaristic mindset can be good people. Although they were otherwise mostly good, this aspect killed my enjoyment.

Also, one chapter started with a short paragraph which managed to gratuitously specify about eight statistics on some (real current world) handgun. I think it was the worst paragraph I've ever read in professional fiction.

Comment Re:Old cellphones get passed down to me (Score 1) 171

My first cell phone (c. 2004) was a hand-me-down of a hand-me-down. It got dumped in recycling when they shut down the cell tower network it relied on.

Second phone was bought new, but close to cheapest available at the time. (It could send and receive text messages!) It got accidentally left in an airport.

Third phone was similarly cheap and new and is my current phone. It has a colour display! And a camera!

I've just been handed-down an Android phone a few days ago but haven't had time to try it out yet.

I'm intending to keep the previous phone anyhow. My internet banking uses text messages for two factor authentication. It is handy to have something too dumb to run malware.

P.S. In /. beta, I couldn't see any comments to the poll. I'm allowing scripts from slashdot.org and fsdn.com.

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