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djsbs

91 karma · joined October 15, 2021

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djsbs··on Chemists discover new way to harness energy from ammonia
A throttle-able test reactor can be as simple as a pool with no pressure vessel. There’s maybe 100 of those in univeristies throughout the US.

Now commercialize it.

djsbs··on Xerox scanners/photocopiers randomly alter numbers in scanned documents (2013)
I wouldnt be surprised if he declares a mistrial with prejudice. The 5th amendment stunt they pulled was jaw dropping.
djsbs··on Xerox scanners/photocopiers randomly alter numbers in scanned documents (2013)
I posted another one 2 days ago, vis a vis the Rittenhouse trial. I was in a rush but I wanted to post something demonstrating how the fidelity of digital tech can be misleading.

In my post I just picked the first main stream media outlet (CBC in my post). today’s post is much better.

djsbs··on Chemists discover new way to harness energy from ammonia
Its a bit complicated. Disclaimer: Im not a nuke engineer, I just took some nuke classes and was surrounded by then for a while.

New reactor designs promise to throttle, but I don’t know if any have been deployed.

This is a bit more complicated than a gas turbine. With a gas turbine, you just inject more gas as needed to keep the turbine turning at a constant speed. The combustion chamber is a violently small part of the whole.

The heat producing part of a reactor, by contrast, is massive. As a result you have thermal gradients, and these gradients are different at different power. They’re also larger at larger power.

A large thermal gradient isn’t a huge problem by itself (engineers have been accounting for this since the steam engine). The problem is the change of gradient itself. As the gradient changes, the materials inside change shape and this causes large mechanical stresses.

The situation is pretty much the same as when you turn off an ICE car: ever hear those ringing or popping sounds it makes? That is the various hot parts cooling and changing shape abruptly.

The problem for a reactor is made worse because material selection is very difficult: you cant just pick any alloy that has good thermal expansion, or good fatigue characteristics. Every alloy must be from a very narrow set of isotopes (not elements!!) that are compatible with the reactor’s neutron environment (balance, distribution, energy spectrum, etc).

djsbs··on Chemists discover new way to harness energy from ammonia
See answer to other comment.
djsbs··on Chemists discover new way to harness energy from ammonia
“ Nukes can operate as peaker plants. The feedback from the control rods is nearly instantaneous.”

But the physical thermal stress from throttling it significantly shorten its lifespan.

Throttling nukes is not a trivial task; I know one plant (Bruce?) doesn't even bother changing the reactor power, they just inject steam into the bay instead of putto g it through a turbine

djsbs··on Image Super-Resolution via Iterative Refinement
And therefore needs to be validated!

The prosecutor literally tried to infer an action from a single pixel. That’s BS and everyone in this forum has the technical ability to recognize this. A single pixel from a low light environment (therefore noisy)?

BS

djsbs··on Image Super-Resolution via Iterative Refinement
And when the prosecution is trying to infer from a single pixel what the defendant was doing, algorithms and artifacts matter.

Just watch the trial.

djsbs··on Image Super-Resolution via Iterative Refinement
I strongly agree with this comment. But this is why digital media is so dangerous - because few people understand the “logorithms” used to light the pixels on the screen
djsbs··on Image Super-Resolution via Iterative Refinement
Then get an expert to testify as much.

Btw, this isn’t a “right wing” issue. Political “liberals”, to their credit, have been saying as much for years, pointing out that closed source software has huge problems in court.

As it stands, the defense has a right to force the prosecution to either get an Apple employee to testify in court, or use a linux machine, gimp and a CS expert to explain what gimp is doing.

EDIT:

sorry I read comment Im replying to as “I wouldn't consider it inadmissible”. I txted this while dozing off.

Leaving comment for record’s sake.

djsbs··on Image Super-Resolution via Iterative Refinement
“ 20 minutes to find an expert?”

They had months to prepare. They’re not noobs they know what the rules are.

The rest of your comment is exactly why council has a right to object and demand validation:

- The judge doesn't know the answer to the question

- Defence doesnt know the answer to the question

- Prosecution, even, didnt know the answer to the question.

Heck, you admit in your own answer that you don’t know the answer - “Id be surprised” doesn’t cut it in court.

As to “logarithms”, defense is not a CS expert and mockery and sarcasm wont get you far in court. An expert will.

But prosecution knew this, and when they did show the still they got ripped apart when defense demonstrated that the pixel that was supposedly a gun was a headlight from a car a couple frames earlier

EDIT:

See a submission I made about the dangers of ignoring procedure and trusting digital data:

https://news.ycombinator.com/item?id=29206833

djsbs··on Image Super-Resolution via Iterative Refinement
If the algorithm introduces materially changes the image, then the opposing council (to the one who introduces evidence) has the right to have the image validated be validated by an expert.

Thats basic court procedure.

Btw, see a submission I made about the dangers of ignoring procedure and trusting digital data:

https://news.ycombinator.com/item?id=29206833

djsbs··on Image Super-Resolution via Iterative Refinement
Is interpolation “super resolution”. Id argue not, but it doesn't matter.

If the software adds pixels to the image than it has made a material change to the picture. Defense has a right to call the prosecution to prove that the zoom effect does not alter the picture.

And its not a moot point. Years ago Xerox started doing OCR (?) on photocopies to same on storage before photocopying (by storing the image as text). Everyone assumed it was a materially identical copy until people noticed it was making typographical and lexical changes to legal contracts in materially meaningful ways. [1]

[1] https://www.cbc.ca/news/science/xerox-copiers-might-alter-nu...

djsbs··on Nuclear radiation used to transmit digital data wirelessly
Rock’s absorption of neutrons doesn’t matter. Neutron thermalize. Since rock has mostly low atomic weight isotopes, it thermalizes them very well [1]. Once they are thermal they scatter easily.

Gauss’ law is for the electric field. The magnetic field is very difficult to block and we have incredibly sensitive magnetometers (probably ones that can detect magnetic anomalies of a submarine from space)

In fact, thats pretty much how deep submarine communication works very low frequency fields. Thats why I proposed a magnet: a basically static field that cant be blocked.

Is my proposal practical? Well, typically not. But if the alternative is neutron communication, I dont see why not.

[1] to a first approx think of thermalizing as momentum exchange upon collision. If you’re similar in mass to the colliding mass you’ll exchange more momentum. Assuming rock is mostly silicon, w/ a mass 28 times larger than a neutron. And there’s at least a km of rock above miners.

[2] throttle a reactor to modulate neutron? Oh boy!

EDIT: actually the crust is mostly oxygen, atomic mass 16. That only strengthens my argument.

djsbs··on Image Super-Resolution via Iterative Refinement
Thats not what they claimed.

They pointed out that the onus is on the prosecution to their get evidence validated. If they want to zoom in they have to get an expert to testify that iOS doesnt add any pixles.

Its pretty basic trial procedure, the prosecution knows the rules and the judge gave them time to find an expert.

djsbs··on Nuclear radiation used to transmit digital data wirelessly
Use a magnet instead then. Flip it over with the pneumatic arm.
djsbs··on Nuclear radiation used to transmit digital data wirelessly
You’re basically right.

Miners trapped in a cave not penetrated by E&M waves?

Wont work.

Signal from inside a reactor?

No. No logic can modulate the signal in said reactor that isn't destroyed by the radiation.

If you have a pneumatic arm to modulate this thing, use it to flip a magnet. That’ll better penetrate any shield than neutrons.

djsbs··on Nuclear radiation used to transmit digital data wirelessly
“… using neutrinos”

“… neutrons will be absorbed…”

I made the same confusion for a second. Neutrons are easily absorbed. Neutrinos (little neutrons) are almost impossible to interact with (and therefore absorb)

djsbs··on Nuclear radiation used to transmit digital data wirelessly
With neutrons, no. They’re slow, isotropic and thermalize easily.

With neutrinos that’d be a different story. They travel at the speed of light (or just below it - depends who you ask) and they aren't readily absorbed by anything. Therefore they can travel through the earth instead of around it.

Problem?

Generation, modulation and detection of neutrinos.

djsbs··on Decades after polio, Martha is among the last to still rely on an iron lung
So they should use the word “managed”. Endemic has a very specific meaning.

If you haven't seen the push for boosters, seasonal shots, etc then you’re not paying attention.

As to assault, you’re right. Legally, the sovereign cannot assault (not even MBS in SA). that being said what the sovereign is doing easily falls into the common law definition of assault:

“An intentional act by one person that creates an apprehension in another of an imminent harmful or offensive contact”

Note the words “offensive”, “contact” and “apprehension”. As my lawyer friend once explained to me, merely touching someone’s arm who you know doesn't want to be touched is assault.

A vaccination necessarily requires that a needle purposely touches, pierces, and injects a foreign substance into another.

If unwanted it constitutes assault, except that the state (as the BLM folks, thankfully, explained last year) has sovereign immunity.

djsbs··on Decades after polio, Martha is among the last to still rely on an iron lung
You clearly haven't read much about the societal impacts of pornography. Being a enthusiastic consumer doesn’t make you am expert.

But, I’ll take you up on your offer. Its better than the one Im currently facing.

djsbs··on Decades after polio, Martha is among the last to still rely on an iron lung
Thats not what endemic means. Endemic means regularly found. The virus is already endemic throughout the world.

Either way these vaccines will not accomplish your stated goal. The vaccines wear off too quickly. The virus bifurcates too quickly. With Pfizer talking about the need for quad shots, you cant manufacture enough vaccines for the world in the various variants present.

However, forcibly injecting people (legal assault) with the vaccines will create a very angry, motivated, minority. A recipe for a society to descend to hell.

djsbs··on Decades after polio, Martha is among the last to still rely on an iron lung
And Im in favor of banning video games, social media and pornography.

Btw, what do you plan to accomplish by assaulting people who don't want it? The virus isnt going away no matter how draconian you get. Just for fun, imagine forcibly vaccinating Afghanistan. Or Central Africa. Not happening. Not without an army (one that can win wars, America’s doesn't count)

djsbs··on CNN goes first two weeks of October without any program reaching 1M viewers
you classify CNN in the same way The Economist is largely segmented?

Really?

djsbs··on Google has a secret deal with FB called “Jedi Blue” that they knew was illegal
I first joined HN ten years ago.

So that was sarcasm? Wow that went over my head. Makes sense though.

djsbs··on Google has a secret deal with FB called “Jedi Blue” that they knew was illegal
I disagree with everything you say, but:

“ They were the first "ethical" tech company,”

What does that even mean? Unless you equate “ethical” with manipulating their dominant social position to shove a worldview you happen to agree with.

Which is a very… narrow understanding of ethics. As well as convenient, and, historically, trite (socially advantaged person agrees w/ the worldview a social institution imposes that reinforces and explains their privilege)

djsbs··on Strict Id Laws Don’t Stop Voters: Evidence from a U.S. Nationwide Panel
Only if they’re legal US persons. Ie they have a green card.

Undocumented, student visas, etc are banned from buying guns

djsbs··on Strict Id Laws Don’t Stop Voters: Evidence from a U.S. Nationwide Panel
You made a solemn oath under penalty of law.

Thats not what they have in the US. I can literally come up with a common name, say Ben Levi, and vote on Ben’s behalf. If Ben decides to show up, he’s in trouble, not me.

In Canada you are typically required ID. If you lied about your grandma and the real Ms. vkou shows up to vote, she’ll have ID proving who she is, and Elections Canada has your name written down to throw you in jail for lying under oath.

djsbs··on Strict Id Laws Don’t Stop Voters: Evidence from a U.S. Nationwide Panel
Wait a second. Canada does require an ID. From someone.

If the would be voter doesn't have ID, then someone who knows them has to make a sworn affidavit that the voter is who they claim to be.

Thats not the same thing as we have in the US

djsbs··on Strict Id Laws Don’t Stop Voters: Evidence from a U.S. Nationwide Panel
You’re aware GA issues free ID for voting, right?

https://dds.georgia.gov/identification-cards-fees

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