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pps43

644 karma · joined October 14, 2015

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pps43··on Max: Boeing 'inappropriately coached' pilots in test after crashes
If Boeing goes under, then Airbus becomes a monopoly.
pps43··on Summary of the Amazon Kinesis Event in the Northern Virginia (US-East-1) Region
> the new capacity had caused all of the servers in the fleet to exceed the maximum number of threads allowed by an operating system configuration. [...] We didn’t want to increase the operating system limit without further testing

Is it because operating system configuration is managed by a different team within the organization?

pps43··on Java is better than C++ for high speed trading systems
You can convert between financial loss and loss of human life using implied cost of averting a fatality [1], which is about $10 million.

[1] https://en.wikipedia.org/wiki/Value_of_life

pps43··on Apple’s head of security indicted in Santa Clara County CCW case
Yet somehow the 1st or 5th Amendment are applied across all states uniformly, unlike the 2nd.
pps43··on It is high time we let go of the Mersenne Twister (2019)
I'm using quasi-random generators where I can, and MCG 128 where I can't.
pps43··on NYC pilot tries mental health responders in place of police
> disarm the police

> they can exercise their right to carry a personal firearm at their own expense

That's not disarming the police, just making them pay $500 out of pocket.

pps43··on Trump's Twitter account hacked after Dutch researcher guessed password?
2020! alone is 5,802 digits long.
pps43··on Russia gives Edward Snowden permanent residency
Snowden is against government surveillance. It's hard to argue he can be used to justify SORM.
pps43··on Russia gives Edward Snowden permanent residency
To be fair, by going after Snowden the US painted itself anti-free speech and pro-surveillance.
pps43··on Trump's Twitter account hacked after Dutch researcher guessed password?
No capital letters, though. It is important to follow all security rules. Weakest link and such. If only his password was Maga2020!, it would be impossible to hack.
pps43··on Trump's Twitter account hacked after Dutch researcher guessed password?
Let's see:

* Letters - check

* Numbers - check

* Special symbols - check

So the new, secure, password should be Maga2020!

pps43··on How to catch a spy that is using a numbers station – The KGB Experience
> if you know the modulation and the frequency the receiver uses

Number stations on short waves all use AM, so you know the modulation. But you don't need to know it, superhet works the same way with any modulation. You need to know the number station frequency, receiver's intermediate frequency, and guess whether its above or below.

> in such a way that there is absolutely no power radiated out of the reception antenna.

I'm not saying there is absolutely no power radiated out of the reception antenna, only that there is not enough power to reliably detect and localize, given the noise and interference from other sources.

If you want absolutely no power radiated out of the reception antenna, you can still do it. Feed some local oscillator frequency, inverted, into the antenna to cancel the remaining leak. But as far as I know, nobody bothers since some leakage is not a problem.

> Any kind of magnetic or capacitive coupler is bi-directional.

True, but in many designs there's also at least one transistor stage in the preamp, and that is not bi-di. There is some stray capacitance between collector and base, but not much.

> Maybe with today's hardware capabilities it would be possible to pull the whole thing into the digital domain at a very early stage

It is possible, but unnecessary. The last radio I built has quadrature sampling detector with FST3253 and handful of op-amps. Most SDRs also do I/Q sampling with two slow ADCs, much simpler than a single high-speed ADC.

pps43··on How to catch a spy that is using a numbers station – The KGB Experience
You can make a small (relative to wavelength) loop antenna that has a sharp minimum, but it will be very inefficient. You want your directional antenna to have a sharp maximum (high gain) so that it can increase signal to noise ratio.
pps43··on How to catch a spy that is using a numbers station – The KGB Experience
There is a big difference between spectrum analyzer hooked up directly to the input of the radio and an antenna in a van several blocks away, with reflections and noise thrown in.
pps43··on How to catch a spy that is using a numbers station – The KGB Experience
A directional antenna has to be much larger than wavelength. Won't fit in a van if we're talking about HF (with wavelengths measured in tens of meters).
pps43··on How to catch a spy that is using a numbers station – The KGB Experience
Initial amplifier does not let much energy flow backwards.

More importantly, there's a lot of background noise on HF bands that will mask that weak signal.

pps43··on How to catch a spy that is using a numbers station – The KGB Experience
Only if it's poorly designed (leaks local oscillator frequency back into antenna) and not shielded.

Modern receivers use quadrature sampling detectors rather than traditional superheterodyne. In that setup any leakage would be on the same frequency and harder to detect.

pps43··on How to catch a spy that is using a numbers station – The KGB Experience
I expected to see something along the lines of vans with directional antennas driving around Moscow listening for spurious emissions from local oscillators of superheterodyne receivers 465 kHz away from the number station frequency, as in Operation RAFTER.
pps43··on On the Use of a Life
There's a good reason why many laws in math and physics have two or three names. They are oftentimes discovered simultaneously by several people and it's not always possible to tell who was first.
pps43··on Coronavirus: Why aren’t death rates rising with case numbers? A UK perspective
The underlying assumption behind false positive rate is that tests are independent and identically distributed. If in practice this is not the case, then false positive rate becomes misleading.
pps43··on Coronavirus: Why aren’t death rates rising with case numbers? A UK perspective
The tests themselves are fine, false positives are due to human error:

"The high specificities (usually 100%) reported in PCR-based tests for SARS-CoV-2 infection do not represent the real-world use of these tests, where contamination and human error produce significant rates of false positives."

New York reports positivity rate below 1% for a while now, so false positive rate cannot be 2.3%.

pps43··on The Lancet: World population projections by 2100
That's not a new idea. Walter Greiling projected back in the 1950s that world population would reach a peak of about nine billion, in the 21st century, and then stop growing [0]

[0] https://en.wikipedia.org/wiki/Projections_of_population_grow...

pps43··on Massacring C Pointers (2018)
No, that would be a pointer to a pointer.
pps43··on The Lancet: World population projections by 2100
> we were taught about the idea of overpopulation in school

That's a problem with school education. They give the wrong models. Exponential growth is impossible in nature because at some point it runs out of steam and fizzles out. Logistic curve or probit is a much better abstraction.

pps43··on U.S. court: Mass surveillance program exposed by Snowden was illegal
Snowden does not have the files. Did not have them when he arrived in Russia. That's why it took so long for the Russians to let him in. They could not believe he did not take any intelligence with him.
pps43··on U.S. court: Mass surveillance program exposed by Snowden was illegal
#2 means that there is no wistleblower protection in the intelligence community.

What else could Snowden have done do to stop the crimes being committed?

pps43··on Russia opposition leader poisoned with Novichok
It's not easy to obtain or synthesize. Terrorists prefer simpler approaches.
pps43··on Level 3 Global Outage
Let me guess: somebody misconfigured BGP again?
pps43··on Bloom's 2 Sigma Problem
I beg to differ. One of my most vivid educational experiences is of my teacher calculating approximate square root on the side of the blackboard when he needed it for something completely unrelated. To me it felt like he was riding a unicycle or swallowing a sword.

Seeing that the audience was perplexed, he reluctantly took a five minute detour and explained Newton-Raphson algorithm, at which point the unbelievable circus trick suddenly became trivial.

pps43··on Bloom's 2 Sigma Problem
I have opposite experience. My parents did not help me with homework beyond first or second grade. After that it was my responsibility, like cleaning my room. I was near the top of my class.
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