Pounding posts into the ground without having to dig a hole, and without pouring concrete.
Monday, September 23, 2024
Sunday, September 22, 2024
Auditory illusion
This is so wild - you hear different words from the same sirens depending what words you're reading at the same time as the sound.
Interactive sculpture?
This sculptor creates art with sugar.
@5:25 the sculpture will melt, unless people ride bicycles to generate electricity to run the air conditioner that preserves it.
Now that's interactive sculpture!
Thursday, September 19, 2024
Human versus AI Geoguesser
I find this a very significant milestone, like the computer that beat the world chess master 27 years ago. Some grad students built an AI platform to guess geographic location over 2 months, and it easily beat the world champion who is superhuman at this task, who has practiced and memorized for years how to recognize a random location. Watch this guy idly talk while doing this superhuman task.
Thursday, September 12, 2024
Cloth concrete forms
Permeable flexible cloth concrete forms facilitate labor-saving rapid construction is unusual shapes.
Barefoot walking
"We didn't evolve to wear shoes."
at 0:13, I think he's saying that cushioning in footwear increases the duration of time that a foot impacting the ground transfers forces to your body, which increases damage.
1:43 The calluses that build up naturally from barefoot walking toughen the surface without impairing tactile sensitivity.
Wednesday, September 11, 2024
Coffee grounds improve concrete
Scientists Discovered An Amazing Practical Use For Our Leftover Coffee Grounds
We could be producing concrete that's 30 percent stronger by processing and adding charred coffee grounds to the mix, researchers in Australia discovered.
Their clever recipe could solve multiple problems at the same time.
Every year the world produces a staggering 10 billion kilograms (22 billion pounds) of coffee waste globally. Most ends up in landfills.
"The disposal of organic waste poses an environmental challenge as it emits large amounts of greenhouse gases including methane and carbon dioxide, which contribute to climate change," explained RMIT University engineer Rajeev Roychand.
With a booming construction market globally, there's also an ever increasing demand for resource intensive concrete causing another set of environmental challenges too.
"The ongoing extraction of natural sand around the world – typically taken from river beds and banks – to meet the rapidly growing demands of the construction industry has a big impact on the environment," said RMIT engineer Jie Li.
"There are critical and long-lasting challenges in maintaining a sustainable supply of sand due to the finite nature of resources and the environmental impacts of sand mining. With a circular-economy approach, we could keep organic waste out of landfill and also better preserve our natural resources like sand."
Organic products like coffee grounds can't be added directly to concrete because they leak chemicals that weaken the building material's strength. So using low energy levels the team heated coffee waste to over 350 °C (around 660 °F) while depriving it of oxygen.
This process is called pyrolyzing. It breaks down the organic molecules, resulting in a porous, carbon-rich charcoal called biochar, that can form bonds with and thereby incorporate itself into the cement matrix.
Roychand and colleagues also tried pyrolyzing the coffee grounds at 500 °C but the resulting biochar particles were not as strong.
The researchers cautioned that they still need to assess the long term durability of their cement product. They're now working on testing how the hybrid coffee-cement performs under freeze/thaw cycles, water absorption, abrasions and many more stressors.
The team is also working on creating biochars from other organic waste sources, including wood, food waste and agricultural waste.
"Our research is in the early stages, but these exciting findings offer an innovative way to greatly reduce the amount of organic waste that goes to landfill," said RMIT engineer Shannon Kilmartin-Lynch.
"Inspiration for my research, from an Indigenous perspective, involves Caring for Country, ensuring there's a sustainable life cycle for all materials and avoiding things going into landfill to minimize the impact on the environment."
https://www.sciencealert.com/scientists-discovered-an-amazing-practical-use-for-our-leftover-coffee-grounds
That's a good thing, because (remarkably) we're running out of sand - at least, 3:21 the rough-edged sand that's good for binding concrete together.
Innovative Electric tugboats
Electric tugs - a significant improvement.
5.3MWhr batteries
5:57 1/10 the noise of diesel-powered
3:13 designed in Vancouver BC
8:37 not useful in locations needing 10 dockings a day (presumably because of charging down-time)
4:11 Motors are mounted vertically, perhaps to make it easier to rotate the direction of the propellers.
6:53 Used in Kittimat Bay guiding ships 159 miles (longest navigation channel in the world) along a narrow inlet to a hydroelectric-powered aluminum smelter. (https://youtu.be/LBDQf5t3rlc?si=Ak1e-4coq1-qHSBa)
Douglas channel:
Monday, September 9, 2024
Unfair algorithms in the gig economy, Uber
Invisible algorithms give riders variable pay for the same work.
Sunday, September 8, 2024
Coffee stir sticks vs spoons
"...despite distributors' assertions that wooden stir sticks are "better" for the environment than plastic ones, they still represent a potentially significant negative impact on the environment–specifically as it relates to the destruction of virgin resources required to make the sticks and the waste generated after their use."
Saturday, September 7, 2024
China hydroelectric dam ambitions
China huge ambitions for 125 GW of hydropower come at a cost, especially the risk of disaster in this earthquake-prone region. Thousands of people and ancient buildings will be destroyed.
Wednesday, September 4, 2024
Bees' monolecty
Some bees have been painstakingly observed to forage from a very limited range of flowers, known as "oligolecty," or "monolecty" if it's truly a single species, which is apparently debatable.
This seems to me to be very expensive for the bee (more travel for less nectar than random opportunistic foraging,) with little benefit, yet very valuable for the plant requiring no effort, except maybe co-evolution of the plant to favor that bee species, which isn't really much "effort."
What evolutionary drive is there for this specific foraging? Is it just that in foraging a specific species they would become "expert" faster, recognizing which flowers have the most yield of how to get the most pollen and nectar efficiently?
A brief review of monolecty in bees and benefits of a broadened definition. 2020
On a realted note, this story of a specific hummingbird and a specific flower co-evolving to benefit each other is equally remarkable.
https://youtu.be/7xRxpicxeFQ?si=_kpTdjXXBhZwE47l
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