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chipsa

1,058 karma · joined August 31, 2014

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chipsa··on Minuteman III test showcases readiness of U.S. nuclear force's deterrent
Sprint was in service for one day before Congress voted to decommission the site.

https://en.wikipedia.org/wiki/Stanley_R._Mickelsen_Safeguard...

chipsa··on Minuteman III test showcases readiness of U.S. nuclear force's deterrent
The economic problem isn't nearly as insurmountable as postulated: A GBI interceptor is ~$70M. A Sentinel ICBM is ~$140M. An NGI interceptor is ~$100M. So already, we see that the interceptors are cheaper than an ICBM (though admittedly about the same order of magnitude). Standard Missile-3 is $10M-$28M (depending on version)

But the cost of the missiles themselves are not the only problem: you have to pay for all the apparatus around the missiles. That's the silos, the command and control, etc. ICBMs demand silos that can survive near missiles from nuclear warheads. The launch control centers need the same survivability. Truth be told, we can't build more. We're refurbishing all of the Minuteman missile silos for Sentinel. You need these to survive to the end of the world, so that you can make sure they people who ended yours also have theirs ended. You also need not just survivability, but assured control. An ICBM launching is the start of a nuclear war. We need to make sure that it doesn't start by accident. The net result is that the Sentinel program is $141B for 659 missiles in 400 silos).

Contra wise, an interceptor needs protection from the elements and maybe special forces attack. By the time the end of the world has come, they have all launched. So the silos are comparatively cheap. The launch control center is cheap. If a missile is launched by accident, it's just money (and a reduced amount of potential defense). It's not the end of the world.

GBI and NGI are National Missile Defense systems. The defended area is limited, but to say that is to underrate how much area is defended. It's all of North America. SM-3 Blk-IIA has a defended footprint equal to half the US (as in, a ship just outside SF Bay can defend out to Nebraska; a ship at Hampton Roads can also defend out to the other side of Nebraska) [0]. NGI even is designed for multiple kill vehicles. Which is to say, it kills multiple MIRVs.

But the problem is that the cost curve is actually the reverse of what you assume: if the warhead can't always get through, and you have to choose where your warheads land, and you don't know which ones won't get through, you have to assume that the defender might just decided that the target you really want dead, is the target they really want to protect. So if the US has 40 interceptors, and can shoot down an estimated 22 warheads with them, I have to paste the Pentagon with 23 warheads to make sure that it's dead. So the other 22 targets that were going to get hit, no longer can get warheads allocated to them. This applies to every other target the Russians want to kill. So suddenly, they don't have 1700 targets to hit with 1700 warheads, they have 74 targets. It will really suck to live in those 74 targets, but the other 1600 some places on the target list are going to be better off. And to hit another target, the Russians would need to add another 24 warheads to their ICBM force. But to force the Russians back to distributing those warheads among the 74 targets, the US would have to kill an average of another 1/3 of a warhead. Recall back that the SM-3 Blk IIA is ~$28M, while a Sentinel ICBM is ~$240M per deployed missile.

This doesn't even get into how the interceptors force the ICBM MIRVs to become less accurate, or hypersonic boost glide vehicles being limited to 1 per launcher, or the fact that we can track HGVs for the entire route, and decoys don't work for them.

0: https://breakingdefense.com/2015/07/aegis-ashore-navy-needs-... image near the bottom shows footprint of IIA

chipsa··on AMD's game-changing Strix Halo, formerly Ryzen AI Max, poses for new die shots
More RAM, so less movement of the weights around to generate a token. Most of the speed limit on a LLM is bandwidth of getting the weights around. To a great extent, your token speed is approximately your (model size)/(effective bandwidth). If you need to shuffle the weights into VRAM from main RAM, you halve your speed (bandwidth used both to move into VRAM and out). If you need to pull the weights from disk, even worse.
chipsa··on Are electric cars that much cheaper to operate?
My wife drives a i3 Rex, which is a plugin hybrid. We’ve taken it on a 6 hour road trip before. It was doable, though I’ll admit it wasn’t the best hybrid for a road trip.
chipsa··on Portable drone jammer uses a Raspberry Pi tactical Software Defined Radio
Your drone has a friend to tag the survivors.
chipsa··on Smoke in the cabin of two 737 MAX caused by Load Reduction Device system [video]
The air handling is exactly the same between the various 737 versions. The difference is that the engines are different. The CFM Leap is designed to shear the bolts on the fan if it goes sufficiently unbalanced, and incidentally the shock of this causes an oil leak. The A320neo will have a very similar problem of filling the plane with smoke if the LRD shears the fan bolts. It just does the air handling slightly differently, so it fills with smoke slower, and the entire cabin, rather than the flight deck first (if it’s the left engine that fails).
chipsa··on The origins of 60-Hz as a power frequency (1997)
Most electric circuits are not rated for continuous load at rated power. The US nominal 15A circuit can only supply 12A continuous. Thus heaters of all types and EV charging being limited to about 1.5kW.
chipsa··on Station of despair: What to do if you get stuck at end of Tokyo Chuo Rapid Line
Most places in the US don’t have alleys. The problem isn’t the alleys, it’s the trash cans. Most modern US cities have cans that can be lifted by the truck, and then emptied. NYC, on the other hand, insists on just leaving everything in flimsy bags, open to the rats.
chipsa··on Take the pedals off the bike
It is generally considered unwise, and depending on age or other circumstances, illegal to ride without a bike helmet, in large part because most places you will meet a car, and if you don’t, wiping out at 15mph is still going to be hard on your noggin.
chipsa··on Nevada court shuts down police use of federal loophole for civil forfeiture
You don’t have an expectation of privacy for the outside of your mail, because people can see the outside. The inside of the mail you do have an expectation of privacy, because someone can’t just see the inside of your mail. Unless it’s smelly, because people have noses.
chipsa··on Nevada court shuts down police use of federal loophole for civil forfeiture
If you never want to get captains to be willing to sail to your ports again… also, manifests can be wrong, or insufficiently descriptive. Manifest may accurately say a container is full of machine parts. But neglect to mention the machine they are parts of is a machine gun.
chipsa··on ShredOS – Secure disk erasure/wipe
Drives which support doing this in hardware have a block just for storing the key. Because it’s not often rewritten, it doesn’t need to go in the pool of blocks that can get remapped.
chipsa··on Feed readers which don't take "no" for an answer
There’s also the option of “If-None-Match”, to make the request conditional. The point is being conditional, not how.
chipsa··on Using GPS satellites to detect tsunamis via ionospheric ionization waves
How does NTP work? GPS is stratum 0. Starlink could be effectively stratum 1.
chipsa··on The era of open voice assistants
I use Lutron Caseta switches for my smart switches.
chipsa··on Engineers do not get to make startup mistakes when they build ledgers
> Merkle hash every entry with its predecessors; normalize entries so they can be consistently hashed and searched; store everything in an append-only log;

Isn’t this how crypto coins work under the hood? There’s no actual encryption in crypto, just secure hashing.

chipsa··on Brick and Mortar Triangle Fraud
Did the stealing occur in your home town? Do you show up in people search tools?
chipsa··on California's most neglected group of students: the gifted ones
Most tests like this are IQ tests, and studying has little impact on IQ test scores, except perhaps showing where you over think things or take too much time. It might get you from 12% to 35%, but won’t get you from 12% to 70%.
chipsa··on California's most neglected group of students: the gifted ones
Surprisingly, the best funded schools are not the ones that are in good places to live. Baltimore city public schools were $22k/student. Howard county was $20k for the same time.
chipsa··on Noise-canceling single-layer woven silk and cotton fabric
Density does not affect the speed of sound of a gas. Temperature and molar mass does. So increasing the pressure of a given composition of gas won’t change anything, assuming you can bring the temp back down. Helium is obviously a different molar mass. But also dry air vs moist air can have an effect.
chipsa··on Oncall shift should be Tuesday to Tuesday
I went in to a hospital at just after midnight, and had my gall bladder out by noon. No, the surgeon wasn’t called in early, but the radiologist who diagnosed the gall bladder was.
chipsa··on SpaceX Super Heavy splashes down in the gulf, canceling chopsticks landing
4 legs have no additional redundancy over 3. One leg failing will still result in the booster tipping over. They do push the maximum angle of tipping before your CG is no longer supported out farther though.
chipsa··on Google’s TOS doesn’t eliminate a user’s Fourth Amendment rights, judge rules [pdf]
The government has totally said “destroy the thing that we said was legal to manufacture, purchase, and own when it was manufactured.” That was the entire point of the bump stock ban, which attempted to reclassify an item that they had previously said was not a machine gun into a machinegun, and therefore illegal to own (and was always illegal to own, so they weren’t going to compensate people for them either).

More strictly, machine guns aren’t banned by the federal government, but rather you have to have paid a tax to own it, and they’ve banned paying the tax for gun made after X date. If they decide to ban the ownership, grandfathering is not guaranteed.

chipsa··on Decoding DME aircraft radio navigation system with the LimeSDR
Probably the required accuracy. VOR is on the order of a degree for accuracy. DME is around 0.1nm. So if you’re 50nm from the VOR, then you may have a position fix error of 0.87nm across the radial, if I did my math right.
chipsa··on How Amazon Became the Largest Private EV Charging Operator in the US
The one car that I sold because it died on me was due to transmission failure. I’m also at 8, and do not expect either of my current cars to ever have a transmission failure.
chipsa··on Mazda’s rotary engine in the age of the electric car
The Volt is a series/parallel hybrid. It has situations where the motor is directly connected to the wheels. The BMW i3 does has a series only set up, but that’s probably because it also has a BEV only version.
chipsa··on JetZero: Ultra-efficient blended wing body jet
https://aviationweek.com/aerospace/emerging-technologies/jet...

Looks more like Max10 sized. It looks like there is a small door behind the wing, which matches the location of the back end of the cabin. There’s no window in them, but they are probably depicting the aft emergency exits, given regulatory requirements that exits be on both ends of the cabin. Based on the cut away, I think the large door aft of the main door, that has no window is likely the cargo hold door. It doesn’t look like there’s a hold under the cabin. The main door appears to be extra wide, which improves the exit capacity of the door, and reduces the actual number of exits required. There’s also the option for a ventral exit, but those are pretty rare on passenger airliners.

chipsa··on The Hawai’i Seaglider Initiative: A new approach to travel between the islands
The small size is actually the point? One of the big problems with the Superferry was the places the ferry went, didn't want to have a bunch of people showing up at once cheaply for... NIMBY reasons.
chipsa··on Inverting PhotoDNA (2021)
PhotoDNA is officially non-invertible, because it’s used for CSAM, and if you can invert it, then anyone having the hashes also has CSAM.
chipsa··on Power over fiber
General rule of thumb: if it's been banned, it's useless for the signatories. Ex: chemical weapons, but also biological weapons, land mines, and cluster munitions. Note that land mines and cluster munitions are still actively being used, especially in Ukraine, and the countries that signed onto the ban largely got rid of those systems well before the ban was signed.
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