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OP you may enjoy Rabkin’s “alien chess” - https://www.markrabkin.com/the-resilience-of-alien-chess/

Since you’re in security, you may enjoy this write up of decrypting the app database with glucose readings and third party API keys - https://www.frdmtoplay.com/freeing-glucose-data-from-the-fre...


Check out the plot in the header, and find the particulate size you care the most about: https://www.frdmtoplay.com/nagivating-air-purification/


Thanks. However note that the site dropped electrostatic filters to simplify things. My understanding is that for non-static-affected particles merv-13 would obviously out perform merv-8 for smaller particles. However the promise of electrostatics is that the materials in the filters create a e-stat field that makes them more efficient re: particles like dust. Certainly the two electrostatic merv-8 filters on my hvac blower capture A LOT of dust (fine particles). Since you clean them in a bathtub by filling the tub and washing the filters thru them, I can attest that there is A LOT of really fine particulates being captured.

The lead line for this article pretty much reflects the reason for my post: "The air purifier marketplace is an apt metaphor for how a particle must feel while being trapped in a filter - at every turn there's a new acronym or regulatory agency or purifier type."


Are you talking about an electrostatic precipitator (metal plates with a power supply) or an electrostatic filter (fibers with a surface charge)? Electrostatic precipitators are neat, but there are basically no standards for them and they’re not cheap to operate. For charged fibers, I see no a priori reason to expect amazing performance or to expect them to remain charged after a bath. If they met MERV 13 standards, they would say so.

In any case, if you see lots of gunk, that’s not the hard-to-filter stuff. I can say, as the proud owner of a monstrous HEPA filter with a dirt cheap noting-special MERV 8 pre filter and an utterly boring metal louver before that, all continuously collecting outsize air, the louver gets a bit gunky, the MERV 8 filter turns black after a while, and the HEPA filter is indistinguishable from brand new. This whole system replaced an older “ISO ePM1” (yes, the manufacturer conveniently forgot the number after that, but it’s MUCH higher spec than MERV 8), and the indoor air quality as measured by a little particle sensor suggested that the ePM1 filter missed about 50% of the outdoor PM2.5, whereas the new system produces air that measures zero across all particle sizes. And that ePM1 filter did a fine job of turning black :)

Get a particle counter and test your system!

P.S. the HEPA system uses less power and will cost less to operate over time because it is HUGE but has the same flow rate.


Thanks so much. The merv-8 to HEPA discontinuity is a great insight. RF.


Yes, hotels were injecting ads on their free WiFi - https://news.ycombinator.com/item?id=3804608


ISPs have been known to do the same thing.


Devil's advocate, but maybe ISPs should all inject ads to make a point. They make money, and anyone using HTTP gets taught a free lesson on what MITM means


Before turning on the dude who thrives to keep the internet free, fix your corporate laptop that does MITM even for HTTPS connections.


"Free" for fraudsters to get their pickings, maybe.


I own a personal laptop?


I haven’t had any problems with OpenNIC: https://opennic.org/

> OpenNIC (also referred to as the OpenNIC Project) is a user owned and controlled top-level Network Information Center offering a non-national alternative to traditional Top-Level Domain (TLD) registries; such as ICANN.


> "Which city are you from?"

Many big tech companies have inclusion training calling this question out as inappropriate on the grounds it provides an opportunity to introduce bias.


Sure, that's advised in interviews, where you're about to make a decision on someone's livelihood, hence the importance of reducing bias. That's a completely different context than in casual conversation at a social event.


This is nonsense as there is no such thing as unbiased personal interaction.


It's a networking event, not an interview loop.

In the same lines, don't ask anything. Everything is a bias. ie, What do they do? - Also a bias as they are engineer, or product, or sales, or whatever.


In most parts of the world this is not true.


Even in the US it's ridiculous advice, driven by fear rather than a rational assessment of policy. Asking people where they are from is just fine.


> Pop tarts and soda provide zero nutritional value

But they have a very high calorie:dollar ratio.


The signage claims the _image_, i.e. the pixels, is deleted but makes no claims about embeddings, biometric measurements, etc that are generated from the image.


You may also be interested in the Work Number product: https://news.ycombinator.com/item?id=29834753


When whole orgs/product lines are cut, you’re laid off regardless of performance.


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