[1]: https://www.opm.gov/policy-data-oversight/pay-leave/salaries...
Fixed math.
204 karma · joined August 10, 2018
[1]: https://www.opm.gov/policy-data-oversight/pay-leave/salaries...
Fixed math.
Typically it's around 300CFM before you should consider a mechanical make-up air device (gravity activated or a makeup air fan tied to the hood activating).
*: Prevention: when tied in you can't make it to a place you can fall such as a system that prevents you from getting within a few feet of a roof
Edit: the link you provide seems to be a lightweight fall protection harness and certainly one I'd like using as I prefer a lighter harness when working at height because it means less fatigue and less chance of a mistake leading to a fall.
Typically the fluid will be air which sucks at moving heat (hence why aerogels are great insulators as they hold a lot of air).
I'm not positive but I suspect that an aerogel in a higher specific heat fluid wouldn't do any better as the flow volume through the aerogel would be quite low bounded by the volume of the aerogel.
If you want to cool the hotside of a TEC you need to push a lot of watts per unit area. The best things for that are high specific heat fluids which are often used in compressor systems and then they're termed refrigerants so you're back to traditional air conditioning. The other option is very cold fluids (liquid nitrogen) but at that point you may be better off bringing the LN2 into more direct contact with whatever you're trying to cool.
Someone else seems to second lower-level standards as the best way [1].
Unfortunately Trump didn't start this trend but I really hope whoever is next stops it.
Also, I love your username in the context of this subthread.
I found it fascinating to read that sentence when I read from the article that routine is critically important. The article didn't seem to say that usefulness or value were what mattered or necessarily considered rather that things were familiar.
More broadly I think that the belief you mention is primarily from the protestant work ethic [1 & 2]. Absent that social norm I'd argue that needing to feel useful and the associated need to work is not part of the fabric of humanity. Feeling needed and feeling that work is a reward is one path to happiness or pleasure but it is not the only one.
I think a case can be made of not wanting to be a burden on a loved one but, sadly & cruelly, at some point dementia robs you of even that worry.
[1]: https://psmag.com/economics/protestant-worth-ethic-real-6554... [2 linked from 1 & more succinct summary]: https://hbr.org/daily-stat/2013/08/there-really-is-such-a-th...
Re: steering wheel buttons in general, it depends on how they're implemented. If you take an old idea [1] and provide tactile locating then it is easy to learn. If you can reuse a common paradigm (a knob for volume) there's no learning required. The steering wheel also is already a busy place - you have two or more stalks nearby, sometimes cruise control is part of the steering wheel buttons and even if not the amount of space means you are forced to provide a subset of functions. A stereo with tactile-marked buttons and knobs is known to most drivers via other paradigms and is easy to swap between cars.
https://www.fcc.gov/document/fcc-fines-florida-driver-48k-ja...
There are also posts at other fora complaining that Hardware Canucks is wrong to suggest that an uncorrectable error should result in an immediate system halt - I leave that argument to those who are interested.
https://blog.dowhile0.org/2017/10/18/automatic-luks-volumes-...
In trying to look for the source I did come across [1] from a few years ago and may have been remembered incorrectly.
Edit: More details at [2], [3], and [4] some noting transient braking may be a factor.
[1]: https://www.npr.org/2013/11/29/247825768/phantom-traffic-jam...
[2]: https://www.vox.com/2014/11/24/7276027/traffic-jam [3]: http://math.mit.edu/projects/traffic/ [4]: https://www.sciencedaily.com/releases/2007/12/071219103102.h...
I recall reading about (highway) traffic being a queuing problem where the arrival rate exceeded the clearance rate due to a transient action (someone tapping their brakes because they were distracted or a bright glint from a glass truck going the other way). If you decrease the arrival rate slightly such that the clearance rate can remove the stopped/slowed cars then the entire traffic flow will return to the norm for the volume of traffic on the road.
Sound? Valid?