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Comment But what percentage of miles driven? (Score 1) 990

But the percentage of miles driven? This number is dominated by vehicles that run all day.

Yes, the vehicles we use for commute and errands can generally be replaced with electrics.

The vehicles for which someone is calculating an ROI run all day and have much bigger engines.

Long haul trucks. Distribution trucks. Farm machines and many others. There is no alternative for diesel fuel for these vehicles and nothing even remotely on the horizon.

If these vehicles stop running billions of people will starve within weeks.

Comment Parachutes, too. (Score 1) 257

Not just floss. Parachutes, too, suffer from a serious shortage of controlled trials demonstrating their efficacy.

Smith, Gordon CS, and Jill P. Pell. "Parachute use to
prevent death and major trauma related to gravitational challenge:
systematic review of randomised controlled trials."
British Medical Journal 327.7429 (2003): 1459.

Article here.

Comment Interactive vs. Passive (Score 1) 159

A good VR experience (and preventing motion sickness) requires fast response time. This requires low latency of the entire chain from the motion sensing device, through the USB connection, OS process scheduling, scene calculation and rendering and any buffering in the video card and display.

A system that is able to respond quickly can obviously produce more frames per second. But just creating more frames per second without reducing latency will not help the experience feel more convincing (or prevent you from feeling queezy). It will just look a bit smoother.

In playback of canned video latency does not matter much. In fact, generating these in-between images actually increases overall latency as the system has to delay the next image while calculating and displaying the in-between image. As long as an equivalent delay is inserted into the audio nobody notices this. But it won't work for VR.

There is, however, a method to produce faster response without calculating more images per second. The most critical movements are those of the head and the change in the scene from such motions can be approximated by simple panning. It's not perfect, but does work to reduce motion sickness.

Comment What's new, what isn't (Score 5, Insightful) 132

Omnidirectional wheels are not new (1949 german parent).

What is probably new here is that the wheel surface is not a discontinuous set of smaller wheels - it's a toroidal tire that can rotate on the in-out axis. This requires the surface to stretch considerably and is probably not compatible with the requirements for car tires. This has real applications, but standard passenger cars are probably not one of them. This car demo is, however, a great way to attract attention and, hopefully, investment. A forklift just doesn't have the same dramatic effect.

Comment There will never be a shortage of helium (Score 1) 190

There will never be a shortage of helium. Only a shortage of really cheap helium.

Helium is continuously produced by alpha decay of radioactive materials inside the earth. It exists in various concentrations in all natural gas reserves.

Some of those reserves (e.g. some wells in Texas or the one now found in Tanzania) have unusually high helium concentrations, making production costs much lower. The U.S. government used the Texas wells to set up a strategic reserve in the early to mid 20th century (when zeppelins were still a thing, and later for the space race).

Towards the end of the 20th century, it gradually sold this inventory into the market, effectively subsidizing it with tax paid by americans during the cold war. This created a disincentive for developing the capability of producing helium from lower grade sources. The uncertainty in the market raised prices, based on the perception of an impending shortage.

Without the Tanzania find, the increased price would have eventually convinced someone to invest in the infrastructure for separating helium from lower grade sources, eliminating the dependency on the chances of finding high grade sources.

Of course, if someone *had* done so, he would have been greatly disappointed by the Tanzania find reducing the price hurt the return on their investment. That's the risk of investing.

Comment "People actually do drugs for fun?" (Score 4, Interesting) 760

There was a question on some forum (perhaps AskReddit) for formerly poor people about what surprised them the most after they became better off.

One poster claimed that he was surprised people with more money actually do drugs for recreation. Everyone where he grew up that used drugs did it to soothe the pain. Everyone knew it. Everyone also knew the price. And those that chose this way were not judged too much.

Comment Universal income (Score 1) 1052

Virtually all countries employ some kind of differential taxation and/or benefits ostensibly meant to help those who have less.

Universal income is just a simpler way and more efficient to implement them. Get rid of all those complex systems. Also gets rid of any incentives for people to be intentionally miserable.

This is assuming, of course, those other systems are dismantled. Many people are employed by those systems or make a living optimizing and gaming those systems. They will will all end up having to look for new jobs. This is the hard part.

Comment Re: Early (Score 2) 51

Startups are defined by rapid growth. It is probably too easy to get uncontrolled and inefficient growth, too. Remember this is not a software company that can support millions of end users per employee. They grow at startup rates with lots of real world locally managed locations.

This is unfortunate but not really surprising.

Comment Let us teach them about information (Score 1) 352

We live in a world of information. So let us teach them about information first. What is information? How has it been encoded, stored, reproduced, processed and transmitted throughout history? What is probability? How does information affect our beliefs about the probability of events? What is encryption? How trustworthy is a source of information? How do we assess that?

Learning about information must include material about the concept of processing information by an algorithm - but actual coding is not necessarily for everyone. Being literate about information is an fundamental skill for anyone who lives in the information age.

Comment Re:More important than the sonic boom (Score 1) 63

... they were faced with the tough task of competing against Concorde, which was already established and flying ...

... and developed with French and British government funding. While the Concorde was operationally profitable for a while, it never made anywhere close to its original development costs. I can understand Boeing sour about it.

Comment Surprise: font doesn't work well when misused (Score 2) 182

The font was designed for reflective white on green. The legibility studies are invalid for black on yellow.

I guess the font designers should have foreseen this and designed a family of two fonts called "negative" and "positive", but I cannot really fault them for failing to fully appreciate the magnitude of human incompetence.

Comment Re:Why not a vacuum? (Score 1) 175

Yes, the air cushion is an issue. I am sure it can be solved, though. Remember that the head assembly of the cheapest optical drive maintains micron accuracy for both tracking and focus distance while the disk wobbles with each rotation (it's never really centered or rotates in-plane). The head is mounted on voice coils and uses active feedback loops.

If you use vacuum and passive magnetic levitation bearings the energy to keep the disk rotating drops to virtually zero. You can have cold storage that is ready to wake up and access in a 100 milliseconds.

Comment CloudFlare have another pragmatic proposal (Score 1) 115

CloudFlare have another pragmatic proposal - require CAs to randomize the certificate serial numbers instead of using predictable sequential numbers. Note that this precaution would have made even MD5 certificates safe against current known attacks.

https://blog.cloudflare.com/why-its-harder-to-forge-a-sha-1-certificate-than-it-is-to-find-a-sha-1-collision/

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