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ew6082

136 karma · joined November 20, 2010

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ew6082··on The Steinwinter Supercargo
Boeing has a similar vehicle that drives the rear end of long load trailers around Seattle.

https://www.youtube.com/watch?v=wsZ6YPsPpj0

ew6082··on Map of Metal
I love it! Was the inability to turn down the volume on the mini player intentional? This had me laughing. I'm at work, but that's metal AF.
ew6082··on Drinking newer groundwater linked to up to 62% higher Parkinson's risk
The way they wrote it is confused and misleading. I suspect it's a corporate piece to sway people to buy glacial-whatever water.
ew6082··on Investigating the Luna-Terra Collapse as a Temporal Multilayer Graph
how about you pick a title that makes it clear its' talking about crypto and not orbital mechanics next time.
ew6082··on Nobody cares
This is the most likely reason. They should have put a sign, but the ramp looks right to me if you want them to match pedestrian speed when merging into a pedestrian space.
ew6082··on It Can Be Done (2003)
I am an Engineer and have done things both ways throughout my career. What is easy to miss in digital are the overall holistic design and the way it all fits together, because you are always zoomed in on a particular piece of the puzzle and rarely see the whole thing on screen in a meaningful way. There is just something about seeing a full design laid out on paper, spread out on the table, that lets many little things jump out at you.

If it's important print it out, in large format.

ew6082··on Lights have been on at this school for a year because no one can turn them off
This was obviously not a good system design, but a box full of relays and PLC controller cost a whole lot less than the all-in employer cost of an extra employee.

They really should also be able to turn off the lights at the breakers unless they did something exceptionally stupid like put the fire control panels on the lighting breakers.

ew6082··on Is this the end of social networking?
The scary part is how much real interpersonal communication data they have on users and what could be done with it in the wrong hands. What is their real business model? It can't just be selling Nitro.
ew6082··on Boeing looked for flaws in its Dreamliner and couldn’t stop finding them
Because gaps like this multiply out at the end of a beam. If for example the abutting structural member relies on that joint for support and is 12 feet long (144 inches) and lets say the flange is 6" across, .005/6 x 144 = .12" which is about 1/8 of an inch of wiggle at the end. If your gap were, say .010" instead, there is suddenly 1/4" of wiggle and when things can wiggle like that vibration gets much worse.
ew6082··on New engine could save internal combustion from the scrap heap
Which is why we usually have multiple cylinders to deliver smooth power. A V8 is getting power on 4 cylinders each revolution, etc.
ew6082··on New engine could save internal combustion from the scrap heap
I see no reason this thing wouldn't lose compression or backflow exhaust gas after wear-in, and wear-in would happen quickly with the cyclic load on those ball bearings. It's a pretty animation but unless they have some spring loading to press the upper and lower rings together the compression (and therefore efficiency) doesn't appear to be durable. There are also some limitations to having a single power stroke per revolution. This can be geared down, of course, but at an efficiency cost.
ew6082··on When did Maytag go bad? (2007)
The newer Speed Queens are barely audible. I have to listen for the water sloshing to tell it's even on.
ew6082··on New AI tool calculates materials’ stress and strain based on photos
Guesses poorly too, based on the examples. The crack growth example is almost laughable. These are nowhere close to where real cracks would form. Cracks start on the inside corner of brittle joints.

The bar stretch is also completely wrong, there are no stress concentrations at the top and bottom; it should be uniform stress or concentrated strain in the center depending on what they're attempting to show.

ew6082··on SpaceX SN9 Explodes on Landing
A static weld is usually stronger than the base metal under static conditions (i.e. not undergoing dynamic shock loading). Welds are created at 3000 degrees C with 50-100C metal right next to it. By the time a weld cools there are always captive stresses, meaning during a failure the weld is the most brittle part. This can be alleviated with pre and post weld heat treatment, but there are always stresses built into a weld.
ew6082··on Physicists challenge Google’s ‘quantum advantage’
Perhaps its a bad article, but I can't see the value of solving the boson sampling problem by sampling bosons having any application in general computing.
ew6082··on Physicists challenge Google’s ‘quantum advantage’
Exactly. This sounds like pure propaganda. They're measuring experimental results and calling it a computer.
ew6082··on The future of electricity is local
Renewables won't buy an industrial power user out of the grid, they need reliability. Also, location is more important than what the power bill is for most industry and commercial. You need a large plot of land for the power to run your average large power user.
ew6082··on Jailbreaking Used Teslas
These are wrecked cars, however. Who is to say that the batteries don't have hidden damage that could cause them to blow on a fast charge and cause a fire? We already know Teslas have fire issues.
ew6082··on Why Does the U.S. Have Three Electrical Grids?
Among US utilities, local public utilities seem to work best. Federal run facilities are deeply mired in bureaucracy and acquisition guidelines, while fully private power companies are prone to get bought out by large investor conglomerates and end up too driven by quarterly profit to invest in maintenance.
ew6082··on Stop Asking Me to “Sign Up” (2014)
Pinterest drove me up a wall with this. I didn't sign up for 4-5 years, and only because I actually needed to see an image for work, because the arrogance was annoying. I have a permanent dislike for their product because of it.
ew6082··on Study suggests that fresh asphalt is a significant source of air pollution
That's for peak power. Efficiency is lost in the deformation bending and returning of the walls of each tire as it rolls. i.e. A really highly loaded tire needs to be really well pressurized to prevent overheating and failure due to the losses.
ew6082··on PDF: Still unfit for human consumption, 20 years later
The use case for 99% of pdfs is email transfer. They are absolutely superior to sending a clunky, bloated MS Word or CAD document. The web archive is just the final resting place in the process that made them.
ew6082··on How Zoom works [slides]
The Skype client of today is just a renamed Lync client, which actually used to be decent. They've done nothing but make it worse since Lync ceased to exist.
ew6082··on Misconfigured Circuit Breakers
It's bad naming practice and only adds confusion to search.
ew6082··on A Sick Giant
It doesn't have to be Christianity, but a nation needs moral fiber to prosper, and not just economically. The decline of faith in America with no underlying moral philosophy to replace it has led to normalization of far too much injustice, monopoly, and downright selfishness. Democracy is on shaky ground these days.
ew6082··on SpaceX's Starship Mk1 just blew off its bulkhead in a pressurization accident
By the time gravity becomes a factor most of that pressure is blown off, though.
ew6082··on SpaceX's Starship Mk1 just blew off its bulkhead in a pressurization accident
It's more like a re-usability factor in mechanical design. Higher safety factor tends to equal fewer cracked welds down the road in anything exposed to vibration and shock. I've only ever heard of one lifting fixture weldment that used a safety factor of 1.0. Every single welded joint was taped instead of painted, and peeled off and fully mag particle tested between each use.

Keep in mind that weld strength is not one single number, it is a wide range. You can inspect a weld with X-ray, UT, MT, and PT methods to narrow the range, but there are still variable heat input, soluble hydrogen content, pre-heat and post-weld heat treatment factors that ALL affect the final hardness/brittleness and ultimate strength of a welded fabrication.

ew6082··on SpaceX's Starship Mk1 just blew off its bulkhead in a pressurization accident
They left the nose cone off to save money. I wonder if the designer counted on some portion of the cone weight to support the cylinder head in their design?
ew6082··on uBlock Origin: Address first-party tracker blocking
It's far more likely that the data obtained about what videos you watch is far more valuable than the cash value of the ads you're not being served. Youtube videos are a very good early interest indicator for advertising.
ew6082··on California power outage triggers chaos in science labs
A private monopoly on its absolute worst day would still operate more efficiently than a federal or state power agency. One still has a bottom line, the other just has meetings to look busy.
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