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jschwartzi

6,010 karma · joined June 15, 2014

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jschwartzi··on Passive radiative cooling below ambient airtemperature under direct sun (2014) [pdf]
You would need a really big roller with a lot of knap too. Although I suppose you could paint most of the midwest and avoid the mountains with a flatter roller.
jschwartzi··on New ‘mirror’ fabric can cool wearers by nearly 5°C
The need for the material to be tight fitting isn’t actually a problem for athletic wear. If you’re wearing a wicking shirt you would also want it to be tight fitting. And a lot of rash guards will be tight because they wick in addition to providing uv protection. So I’m skeptical that the researchers really understand the applications for their material. There’s also no discussion of how it performs when it gets wet.
jschwartzi··on Amazon destroying millions of items of unsold stock in one of its UK warehouses
A lot of what gets returned is plastic garbage that doesn’t even do what it says it does
jschwartzi··on Amazon destroying millions of items of unsold stock in one of its UK warehouses
No Amazon definitely destroys most returns. I was informed that anything you can take to a Kohl’s is destroyed after return. That’s why sometimes it’s not available as an option.
jschwartzi··on Alpha-Gal Syndrome
I’ve had a couple of ticks here in Washington. They’re more common in Eastern Washington.
jschwartzi··on Alpha-Gal Syndrome
permethrin is a contact neurotoxin that will kill or repel most insects. I treat my hiking clothes with it if I’m going into tick country. I’ve actually watched ticks scurry away and die after they make contact with treated clothing. It kills mosquitoes equally effectively.

It’s really bad for fish though so I don’t use it all the time.

jschwartzi··on Your CPU may have slowed down on Wednesday
A Qt install with all the bells and whistles is about 500 megabytes, so it’s very comparable in size to Electron. Qml is a lot easier to develop in than Node+browser though.
jschwartzi··on Humans are more dependent on water than many other mammals
starch can also stimulate the uptake of water in your small intestine. Oral Rehydration Salts combine some dextrose and salts to mix into a liter of water. When properly mixed the salts are in a homeostatic quantity and won’t affect the salt balance of existing tissue. So you can drink them to recover from severe dehydration without risking hyponatremia.
jschwartzi··on Ohio Republicans close to imposing near-total ban on municipal broadband
A lot of people can’t even afford to put down a security deposit on a new rental. Moving is completely out of reach for them.
jschwartzi··on Ohio Republicans close to imposing near-total ban on municipal broadband
Ziply was awful. We got screwed by them when they bought the fiber network in our area, canceled our autopay, and then didn’t bill us for three months until we had racked up a bunch of late fees. My wife spent hours on the phone with them getting the issues sorted out. It was the worst customer service experience I’ve ever had with a broadband provider. I’ve had Charter, Qwest, and Comcast.
jschwartzi··on Anybody notice when you cross a north/south avenue Bluetooth start freaking out?
2.4 Ghz is a very busy spectrum, and most protocols use some form of collision detect to avoid interference, so it’s probable that the spectrum is particularly busy in that area with the clear line of sight and buildings at four corners. Imagine at least one WAP for every floor times four. And recall that the received signal increases with height. The issue could easily be interference from Wifi devices. And there might be some interference from the other bluetooth radios. There’s also 802.15.4 in the spectrum, which gets used for wireless sensors.

I’m increasingly surprised all this stuff works in that spectrum

jschwartzi··on Sperm DNA methylation epimutation biomarker for paternal offspring autism
Some nitpicks: * IVF involves retrieval and then fertilization of eggs. There’s not usually leftover unfertilized eggs unless the woman is banking her eggs. * The success rates my partner and I have been quoted mean that we want to keep as many embryos as possible in case we need to try again. I think it would be really unethical to ask a woman to give up any good eggs or euploid embryos as they can be hard to get in some cases.

The shots a woman has to give herself daily to stimulate follicle production are no joke. That would be a lot to put someone through purely for research. It’s not as simple as that. And it’s wishful thinking to expect any woman to do that.

jschwartzi··on Althttpd: Simple webserver in a single C file
That class of errors is not an issue here.

This program isn't meant to be multithreaded, it's meant to be multi-/process/. The difference is that each instance of the application has its own independent address space. So that's one address space per instance. And because of that there are no threading issues. Also as a result any communication between different processes has to be explicitly defined.

Making this program multi-threaded would be a big mistake because then you couldn't use any of the HTTP proxies out there to monitor for connections and hand them off to this program.

This is arguably a much better architecture from a safety/security standpoint then trying to spin multiple threads each sharing an address space. It forces you to use OS-provided mechanisms for shared state rather than simply manipulating the memory to share information.

jschwartzi··on “It's a truck full of traffic lights”
I mean it makes sense. If you've never seen traffic lights be delivered to a new intersection you'd probably blithely assume you'll never encounter a stack of them that are unlit and moving.

Somewhere at Tesla there's a junior engineer who's telling a senior engineer "I told you so!"

jschwartzi··on “It's a truck full of traffic lights”
I just figured out how I can make sure self-driving cars stop for me when I'm trying to cross a street. Dress up as a red light.
jschwartzi··on Immediate skin-to-skin contact with unstable newborns improves survival chances
The point I'm making isn't that you can't get insurance, it's that the insurance you have changes every time you change jobs. At one employer you might be on an HMO plan like Kaiser Permanente and be limited to their providers. But then your next employer uses Blue Cross / Blue Shield or United Healthcare and you can no longer use your Kaiser Permanente doctors. So you're not guaranteed continuity of care, and you might lose coverage for certain optional things if you change jobs. And your costs, which are nebulous to begin with, might change substantially depending on who your employer is. It's a crap shoot.

Also you're not required to have insurance. The individual mandate was repealed a couple of years ago.

jschwartzi··on Bring back the station wagon
Yeah, and the "midsize" trucks from 15 or 20 years ago are the same size as the full size trucks were 15 or 20 years ago. Everything is getting way bigger and harder to drive. I'd much rather have a Toyota Tacoma or Ford Ranger from 20 years ago on a forest service road than an F-150 built now.
jschwartzi··on Amazon refused to refund $7k after shipping an empty box instead of a Sony A1
I wouldn't buy anything I need to trust on Amazon.
jschwartzi··on Immediate skin-to-skin contact with unstable newborns improves survival chances
But when you change employers you risk losing access to your healthcare. Whereas if government pays for the health system you can maintain continuity of care, which can be essential to treat various psychiatric and medical conditions. Imagine if, because you got a new job, your lease on an apartment were canceled and you had to go find a new place to live? That's what our healthcare system is like and it's maddening.
jschwartzi··on When Do Programmers Retire? Is 35 the End?
Yeah the assertion that older developers don't have time to learn new things is especially stupid. I'm 35 and I just wrote an entire playbook on how to move my employer off of some obsolete VM-based infrastructure and into the Azure equivalents. A month ago I didn't know shit about any of this stuff. But I know enough about networking to be able to read the Azure docs on all their platform components so I was the only person on my team of 7 who could formulate this plan. I learned it all on the job by reading the documents.
jschwartzi··on Tesla Rescinds Job Offer
Given how they've treated him I wouldn't be particularly worried either.
jschwartzi··on Tesla Rescinds Job Offer
Isn't this promissory estoppel? Like they promised that you would start at a certain date, causing you to quit your current job. Then they withdrew the promise, causing you to be unemployed.
jschwartzi··on 2022 Ford F-150 Lightning
> * All of the weight is in the bottom of the vehicle, giving a lower centre of gravity. I'd bet this will kill the old F150 in a moose (or child!) test.

The important thing to note about the moose test is that it doesn't specify that the moose has to survive. It's simply a test of whether the occupants will survive hitting a moose. I would wager anything that is designed to pass the moose test will kill anything that it hits that is below the moose's center of gravity. So actually the vehicle is way less safe for pedestrians than a vehicle that would fail the moose test.

But if all that matters is the safety of the occupant I guess this is okay.

> * The lack of engine means the entire front part of the car is a huge crumple zone. This gives designers more wriggle room for pedestrian protection too. This is an increasingly important requirement in road safety standards.

The kind of "crumple zone" that enhances pedestrian and cyclist safety is more like a beer can. Again, the crumple zones in this vehicle are designed to keep the occupants safe but not designed to keep any other road user safe.

jschwartzi··on A fungus that infects cicadas and pushes their mating into hyperdrive
Have you ever had athlete's foot or jock itch?
jschwartzi··on Poor in Tech
I can think of at least one society that formed in the 1930's for which this was an absolute mandate! But I don't recall reading much about them past about 1945, so perhaps you should do some further research.
jschwartzi··on Getting High-Speed Rail Wrong
The central question is how was the land abutting each station zoned? Did they change the zoning to allow for more development? Or did it remain mostly residential-zoned and just change from single-family to multi-family?

The reason rail works beautifully in other countries is that you can get off the train and walk to useful destinations, even if where you disembarked isn't where you live. Shinkansen in Japan have tons of shopping, nice restaurants, and hotels all within a block or two of the station. So there's a reason for non-residents to stop as well as residents. And because everything surrounds the station there's no point for residents to go anywhere else.

jschwartzi··on A police dog who cried drugs at every traffic stop
If I took a test in college and got 40% of the answers wrong I would get an F.
jschwartzi··on The Return of Fancy Tools
Linear.app is way faster and tighter than JIRA, but lacks a lot of features that I actually really need in my job:

* Advanced Roadmapping - JIRA will, given a pile of issues, sort them and fake-assign them to individuals on your team to determine how long it will take you to complete a project. This is way more powerful than burndown charts and cycles when you're planning a hardware project with a tightly-defined deadline. Without it I have to drop back to spreadsheets to provide any insight into when a project will be completed. It's especially important when the business peels engineers off the project.

* Time-based estimating - JIRA lets me plug hours in for estimates instead of railroading me into T-shirt sizes, which means I can actually use the tool to give an accurate estimate of when we'll be done. Linear requires you to calibrate your expectations by running a few cycles first, which makes it a really bad fit for projects that have a defined end date.

I think Linear has a lot of potential for teams that don't work to fixed deadlines, but for my purposes it's just a very fast spreadsheet.

jschwartzi··on Texas lawmakers approve bill banning 'meat' & 'beef' on plant-based food labels
For culinary use Beyond is a meat. That differs from the biological definition but most people understand that.
jschwartzi··on Getting High-Speed Rail Wrong
Nope, you're totally right. The devil here is entirely in the details.
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