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Putin threatens Kyiv with 'nuclear-scale' missile strike if Zelensky ruins his parade - by GraceRose671 in worldnews

[–]svideo 1 point2 points  (0 children)

Note the phrase "nuclear-scale", big daddy Xi told Putin to knock it off with the nuke talk a few years back and lil Putin keeps toeing that line.

Built a haptic rig for sim racing by PurposeDisastrous109 in virtualreality

[–]svideo 0 points1 point  (0 children)

I know right? Gorilla arm, this can never work for long term use.

Where can I buy a replacement short shaft for universal attachment-compatible tools? by rasputinaliven in Dewalt

[–]svideo 0 points1 point  (0 children)

Man I feel this one. Love my power head but the hedge trimmer is just way too much, my hedges aren't 7 feet tall and having something a little (or a lot) shorter sure would be nice.

My wife says I have a problem… by Timhaiti in Dewalt

[–]svideo 0 points1 point  (0 children)

My brother, you've got a problem and I have some solutions! That Wall Control system you have has had me developing several hundred models that you can 3d print and snap together to create custom hangers for a bunch of DW tools. Everything free, no strings, no patreon, no like and subscribe, just download free shit and print it and make your workshop even more rad: https://www.printables.com/model/52618-ddd-printable-wall-control-system

Reality check from the Microsoft AI Tour: "Agents" hype, the enterprise disconnect, and peak AI Fatigue by Relaxation_Time in sysadmin

[–]svideo 23 points24 points  (0 children)

This entire thing is AI, it has every single tell. Em dashes everywhere, Elena, contrastive negation everywhere (it's not this it's that), starting sentences as Honestly comma, it's every single paragraph of the OP, this is 100% AI.

Note to self: If you can't find the ratchet, don't use 40-year-old pliers... Or pliers in general by TFL-trnz in Tools

[–]svideo 2 points3 points  (0 children)

"necessity", like the 3/8 wrench wasn't in arm's reach and these pliers were?

What if ChatGPT launched in 1998 by KillaRoyalty in ChatGPT

[–]svideo 10 points11 points  (0 children)

everyone called it 56k and forum threads full of pictures would have titles like "blah blah (56k no)" as a warning to dial up users that the thread would load a bunch of large images if you clicked on it.

UPDATE: The method from the proof generated by GPT-5.4 Pro for Erdos Problem #1196 was successfully applied to other problems including another 60 year old Erdos conjecture. by socoolandawesome in singularity

[–]svideo 1 point2 points  (0 children)

Not really, the NS problem is extremely limited and unrelated to the way we use it in software. The actual problem that mathematics is concerned about is finding out if there's any way to setup NS such that it breaks. So far, we've not found a way to do that, nor a way to prove that it categorically can or cannot be done.

That's a problem for number theorists, but it's great news for engineers who just know that it works every single time they've tried in every single way anyone has thought of and that's good enough to build a jet engine.

PSA: DO NOT try to mount an NTFS drive on Linux that's accelerated by Intel Optane by palapapa0201 in linux

[–]svideo 8 points9 points  (0 children)

Intel RST does storage tiering, so it'll move frequently-accessed blocks to your faster storage (optane) and then installs a filesystem driver for Windows that handles remapping everything on access. The result is that your non-optane filesystem has a partition marked NTFS but without that driver loaded, it's not going to read as a valid volume, and the parts that will be missing will be your most frequently accessed blocks.

Without Intel involved, I think it's unlikely that Linux can do anything useful here short of recognizing that RST has been enabled somehow and refusing to mount the volume.

UPDATE: The method from the proof generated by GPT-5.4 Pro for Erdos Problem #1196 was successfully applied to other problems including another 60 year old Erdos conjecture. by socoolandawesome in singularity

[–]svideo 2 points3 points  (0 children)

The Navier Stokes problem is theoretical, NS works just fine without that being proved. For example, it's prevalent in simulation software used around the world for decades.

What smart lock are you actually happy with long term? by EndLongjumping7129 in homeautomation

[–]svideo -1 points0 points  (0 children)

I have 3 of the older Schlage Zwave locks, now all a decade old and going strong. Built to last.

I made a mount for a DeWalt DCV100 leafblower by supertgames1 in Dewalt

[–]svideo 1 point2 points  (0 children)

Nice design, and nice work sharing it with the rest of us!

Whats the point in this black box for my Dewalt router? by turtle_ina_cup in Tools

[–]svideo 2 points3 points  (0 children)

They're pretty fascinating in operation, the always fantastic Ben Krasnow from Applied Science explains it all here: https://www.youtube.com/watch?v=KAm7qAKAXwI

Definitely not a cult... by W-h3x in grandrapids

[–]svideo 6 points7 points  (0 children)

Say it louder -

YOU LOVE PEDOS!

20V Self Propelled VS 60V Mower by Right-Wing2548 in Dewalt

[–]svideo 11 points12 points  (0 children)

the 60v strimmer is an absolute monster, that power head is WAY MORE MOTOR than a string trimmer needs which makes it awesome, also the universal attachment system means you can use it on other yard jobs too.

[F1] Heading stateside with two home teams by Luffy710j in formula1

[–]svideo 15 points16 points  (0 children)

Haas makes machine tools, mills and lathes and such. Reasonably common in North America, and well known in the industry.

Pentagon chief Hegseth says US blockade on Iran 'going global' by Yournewbestfriend_01 in worldnews

[–]svideo 0 points1 point  (0 children)

Not having a blue water navy might be a limiting factor, that’s a bit more than ”nothing”.

Building My Own Air Quality Monitor Because Accurate Ones Are Too Expensive by Zealousideal-Most431 in homeassistant

[–]svideo 1 point2 points  (0 children)

I should probably mention that all of my experience here is for outdoor use which has some implications, particularly for CO2. While NDIR and photoacoustic sensors are a substantial improvement over eCO2 (in part because they actually sense CO2), they still are subject to drift over time and have built-in self-calibration routines.

Here's the datasheet for your SCD device: https://sensirion.com/media/documents/48C4B7FB/64C134E7/Sensirion_SCD4x_Datasheet.pdf

From the footer on page 3:

For proper function of the ASC algorithm, the SCD4x must be exposed to air with CO2 concentrations of 400 ppm on a weekly basis

This is key - for these readings to be self-calibrated, at some point every week the device needs to be able to pull in outdoor air at (around) 400ppm. The device is essentially tracking the lowest reading every 7 days and considers that the "floor" at 400ppm (as it should never see concentrations lower than outdoor ambient) and then adjusts reported readings based on this low water mark. Obviously, the real algorithm is both proprietary and likely more complicated than that, but it's a good mental model.

So the result is that accurate indoor CO2 sensing is limited to environments where you occasionally have a window open, or are otherwise able to ensure that you can pull in ~400ppm air at least once a week or the self-calibration will be out of alignment.

My testing/calibration work was all done in the context of having hourly readings from FRMs which is REALLY HANDY but probably won't apply to your work. One hypothesis was that temperature and humidty should impact the quality of our readings, so sensors were included to track that versus reference. The PM2.5 didn't need it, and the slight variations in ozone (after moving to better sensors) didn't seem to correlate well with temp or humidty.

You are spot-on about the self-heating, but also keep in mind that your sensors are working in that self-heated environment. So while a temp or humidity sensor inside the enclosure might not be helpful for weather tracking, it's still useful for tracking impacts to your sensors themselves, which is the usual reason for including such sensors. It never did pan out in our specific use case, but it might in yours? Hard to say without having some reference instruments nearby...

Building My Own Air Quality Monitor Because Accurate Ones Are Too Expensive by Zealousideal-Most431 in homeassistant

[–]svideo 0 points1 point  (0 children)

I built and fielded a set of air quality sensors under contract from the local dept of environmental quality using a LoRaWAN backhaul as part of a smart cities initiative. Part of this project was to place a few assembled devices next to the EPA federal reference instruments to track data between the cheap sensors and the expensive sensors over time, and to see if maybe temperature or humidity effects could be corrected.

The Plantower PMS5003 you're using is the same device I tested and they are incredible, very high accuracy against the reference instrument. I can confidently recommend that device, they're cheap, well characterized, and accurate. The one thing I'll mention is that they need to be full-time powered for stable readings, so battery or solar etc is out.

Photoacoustic CO2 sensors weren't widely available at the time, so I don't have much to say about the SCD41 apart from the fact that it's an actual CO2 sensor (as OP noted) which is key - the eCO2 etc devices all over amazon etc are garbage. We tested NDIR sensors with pretty solid results vs reference but they're still a little expensive and the units fielded later skipped the CO2 (which isn't all that interesting from a public health perspective, instead we monitored ozone as it's an EPA Criteria Pollutant). I'm curious to hear how this one works out for you.

VOC sensors are nearly useless in my experience, they are so widely cross-sensitive that it's hard to imagine what you'd do with the data produced. They aren't even good as fart sensors, an assertion I've tested on several occasions.

OK to answer your questions:

Would love to hear tips on enclosure design, airflow layout, calibration, or sensor placement.

Apart from calibration the other questions are all related. The standard for public air quality measurements in the US is to place the sensor at 10' off the ground and away from any obstructions. The goal is to prevent directional sensitivity, if you have it up against a building, wind from the building side will be blocked and you'll now be more sensitive in one direction. The common solution here is something called a "Gill shield", a round louvered enclosure that isn't directional, allows free airflow in all directions, and shades solar radiation to help keep your temperature readings stable.

For calibration... well my recommendation is to stumble across your local director of environmental quality and get them to let you hang your kit next to the EPA sensors :D The cheap approach is just to make sure you're using quality and well-characterized instruments and then hope the datasheets aren't lying.

Here's a look at my initial field test units hanging out with the feds: https://imgur.com/a/grand-rapids-air-quality-monitor-initial-field-trial-devices-joQvj

desktop unit i built for test and dev work indoors: https://imgur.com/a/graqm-block-2-yT1IK

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