Ted Cruz is going to hold what looks to be an interesting hearing next week.
Category Archives: Technology and Society
Hyperloop
Several proposed routes. Some make more sense than others, to me. I’m surprised there’s no LA-Vegas.
An Ignominious Record
We are now into the longest gap in our ability to get Americans into space on American rockets since Alan Shepard flew.
The long gap was caused by our risk aversion, because "safety," not returning America to space, is "the highest priority." https://t.co/bI0SYEDHHm
— SafeNotAnOption (@SafeNotAnOption) April 18, 2017
Not Sure Whether You Should Try This At Home
Mass producing sugar rockets.
[Update a while later]
Over at Arocket, it is pointed out that probably the most hazardous thing with this is not the propellants, or tamping them, but potential shards from PVC casings.
The Outer Space Treaty
Bob Zimmerman says that Trump should open up the solar system by renegotiating the deal.
How United Happens
Thoughts from Charlie Martin.
It’s very clear that this wasn’t caused by overbooking per se, and all of the outraged economic ignorance about it would be astounding if I didn’t see so much economic ignorance in general.
AI In Medicine
Self-taught systems beat MDs at predicting heart attacks:
All four AI methods performed significantly better than the ACC/AHA guidelines. Using a statistic called AUC (in which a score of 1.0 signifies 100% accuracy), the ACC/AHA guidelines hit 0.728. The four new methods ranged from 0.745 to 0.764, Weng’s team reports this month in PLOS ONE. The best one—neural networks—correctly predicted 7.6% more events than the ACC/AHA method, and it raised 1.6% fewer false alarms. In the test sample of about 83,000 records, that amounts to 355 additional patients whose lives could have been saved. That’s because prediction often leads to prevention, Weng says, through cholesterol-lowering medication or changes in diet.
To be honest, while it’s statistically significant, I’d have expected a bigger improvement than that. And it’s not clear how useful it is if the recommendations aren’t science based, as prescribing cholesterol-reduction or diet change generally aren’t.
Terraforming Mars
“The rate of loss of gas today is very low — slow enough that it would take billions of years to remove the equivalent amount of gas that is in the atmosphere,” principal investigator Bruce Jakosky said in an email. There is some CO2 left in the polar ice and in carbon-bearing materials, he added, but not nearly enough to warm the temperature significantly if it somehow was put back in the atmosphere.
“There isn’t a source of CO2 that could replenish the atmosphere — even outgassing of CO2 from volcanoes has got to be incredibly slow today,” Jakosky added. “If we wanted to put enough CO2 into the atmosphere to raise temperatures significantly, it would take something like 10 million kilometer-sized comets (if they were all made entirely of CO2). This is just not feasible.”
I think there are other possibilities (e.g., bombarding it with carbonaceous and other asteroids, and comets, and manufacturing the CO2 on the surface), but largely, I consider the obsession with Mars to be much more romantic than practical, at least as a new earth.
Climate
The good, the bad, and the null hypothesis.
The New Air Force Launch Procurement
Some thoughts from “Main Engine Cut Off.”
I’m glad to see that Congress isn’t pushing the AR1 as hard as it’s been. This looks, ultimately, like bad news for AJR. They’re going to have to become more competitive if they want to maintain their business. They’re trying to do it with printing engine parts, but I don’t know if it will be enough. They’re going to have to really slice overhead, I think.