- If you pressurize something "incompressible" like water under a cap of impermeable rock you are to still compressing the water and compressing the surrounding rock. The whole industry of fracking operates on compression rock to the point of fracturing it and forcing open the cracks. At 600-1300 bar water compresses 3-6%. It's the "equivalent" of a reservoir at the height of everest or higher.
- Where did the "libREated" in the title come from?
- I get that, what's hard is if my made up chip designer is commenting about UI coding or networking topology or something closer to HNs heart.
- The thing that's hard about the intellectual curiosity part is knowing what comments are from actual experts and what are very smart people opining outside the edges of their circle of competence - while still sounding smart.
There was a discussion here where a professor with a specialty on the underlying subject was 'corrected'/crowded out by very detailed comments that sounded cogent, had buzzwords in them but ultimately were incorrect.
Seeing that makes me wonder about the discussion here on topics I know nothing about. Vetted flair for subject matter expertise for users would help. I'm still interested in what a chip designer has to say about astronomy but it would make it easier to weigh the contribution.
- We tried Windows 2000 Professional for the DEC Alpha for a GIS system in the late 90s. Suddenly made the $5000 PCs that could run it seem cheap.
- What is the last node/cpu that had the smallest features visible at optical microscope scales?
- And the lesson every us pol seems to have learned is "use signal, use protonmail."
- Am I remembering it wrong or did Microsoft use an undocumented call in excel to grant it more memory than was possible for early competitors who didn't also write the OS?
- They are made in TN and they sell 10-20k per year.
- Now come on, that's not fair. The apple pro display stand is an inert piece of metal with a hinge and some springs and it only costs $999.
- We have a manhole outside our house and it was inspected like this. I work with GIS for electric and gas companies. I used to keep small ear protectors in the Burley so me and the kids could go up and ask "diggermen" about holes in the road.
Xcel used directional drilling for a plastic gas main down our street and then did sewer intrusion inspections after. A neighbor had their sewer line pierced. It's a hazard because it isn't detectible until the sewer line blocks and then the blade thingy the plumber uses can sever the plastic gas service lateral in the sewer line.
There is a gas overflow valve (like a ball bearing that too much flow can push in to block the pipe) back at the service tee fitting on the main. If that doesn't work then you could have a gas explosion in the sewer or house. It happens and it is bad. Clients give presentations on these projects at conferences (e.g. use GIS to combine the sewer and gas topology to identify where the crossings are.)
That truck isn't for inspecting your sewer, it's for inspecting every junction on that sewer line, 8 hours per day, every day. They will have a map and linear reference showing where every other underground utility (fiber/gas/electricity) intersects it and be recording and cross referencing it in case it needs to be produced in court at a later date.
People are conflating do-you-need-a-$30k-sewer-line "plumber inspection" with this service. This kind of inspection is more like the "assuming tort liability" role that the companies like sitewise serve. Even with the robot done and packed, the operator in the truck was working for a bit, making copies of the videos and tagging them and stuff. If your gas main piercing a sewer causes explosions the settlements can be in the tens of millions.
BigUtility uses trenchless directional drilling to poke a drill horizontally down the street and then laterally to each house saving millions of dollars in open trench costs. The gotcha is that they can't see where they are digging and thus can burn, electrocute, explode or kill taxpayers. The inspections help with sewer maintenance / cleaning but the big money/concern is on the liability for cross bored gas lines.
The robot (the one I saw outside my house) was over $10k and kitting out the whole truck with a crane and the monitors and reels was $90k. They hosed the robot down completely with high pressure water from the truck once it came back out and checked it over for damage. That and the fact that the van guys typically don't go in the sewer is why the van is clean. It's an "expensive equipment" van, not a plumbers van. For comparison the fiber optic inspection a plumber might use is more like $2k and you can rent them.
Depending on the job they can inflate a balloon at the next manhole upstream or even pump/route the sewer through a temp pipe on the street surface (looks like a big fire hose) from the previous manhole to the one after where the van is. That needs 3 crews plus flaggers for traffic. They use a radio to coordinate with the other crews.
With the line blocked for inspection the robot typically just has a film of that nasty sewer grease on it.
They told me the door stays open even in winter because the crane operator / tether wrangler guy is right by an open sewer which is a fall and methane hazard.
The job isn't quick - there might be 300 feet / 100m of line to the robot near the next manhole. Unless they were just looking at one service main, if they were able to leave they must have been winding up already.
The more important question is: is there a sewer manhole where they parked?
If we can surveil people with drones from miles away, what technology are the FBI using that requires guys physically in a van outside a house? If you were going to park outside, why would you use a method that usually blocks the street?
I dug up a pic. If you look carefully you can see two tethers, one for the 4 wheel metal sled that moves it and a thicker one for the camera and lights on the "head" part. The crew used the controls to move the head around until it was looking at my kids and they could see themselves on the second screen (one screen faced out the door.) The kids thought it was cool: https://i.imgur.com/2ltz8bj.png
Story about a fatal explosion caused by horizontal directional drilling piercing a gas main:
https://www.cnn.com/2013/03/13/us/missouri-gas-explosion/ind...
I can't find any conference papers but the industry term to google is "crossbore" and this blog post has some pictures of gas service laterals piercing sewers:
https://blog.envirosight.com/sewer-school-preventing-cross-b...
ESRI page on using GIS to identify the potential crossbores and assign them 90 day inspection windows to try to detect it before the sewer backs up:
https://community.esri.com/t5/gas-and-pipeline-blog/arcgis-f...
- The fact that US gdp and population has grown while energy inputs have stayed flat is an important measure of both the energy efficiency of an economy and the mix of sources of gdp. "Energy intensity" is a measure of PPP gdp per capita per kg of oil. If you want to grow your economy then you either improve energy intensity (get more gdp for the same or less energy) or find new energy sources. China wants to reduce their energy intensity. Yet the author is showing a "graph goes up" to mean "better" with all the confidence of an engineer outside their circle of competence. The US energy intensity has halved since the 1980s - less oil and more IT.
- >and two “scanners.” The purpose of the scanners was to stand by the B-17’s rear doors and keep lookout for other aircraft
I spoke to one of the CAF "scanners" when the B29 "FiFi" visited nearby and he said one of their roles was to watch for smoke in case one of the engines caught fire. The engines are "upgrades" from just after the war.
- When my american kids are slagging my Belgian half brother he shuts them down by offering a visit to the school he went to, you know, through the unlocked non bulletproof front door. Their schools have vestibules with intercoms and such.
- "Slower than bubblesort" is the acheivement here.
- Add bubble sort in parallel and race them against each other!
- To get a video card during lockdown someone gave me an invite to a micro center fan discord where people would post timely photos of what was on the shelves. They would also post photos of their crazy hardware, one of which was an air conditioner duct window insert feeding outdoor air to cool the GPUs (mining rig) and exhausting the hot air into a grow tent.
- In Boulders case the goal wasn't to strand rural customers with resiliency costs but to reduce emissions. Xcel moved in that direction enough that Boulder didn't need to municipalize. Owning poles and jiggling electrons would have allowed the city to do things like let homeowners access the 4% muni borrowing rate for solar loans that stay with the property via a tax lien. With the existing structure of public regulator and local monopolies, Xcel can't easily do anything "special" for Boulder without forcing poor rural places to share the costs.
Someone didn't read the 26 year old Webvan case study at CEO-school.
https://www.hbs.edu/faculty/Pages/item.aspx?num=26728