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Comment Claims in patent applications (Score 1) 201

1. Inventor makes some new and non-obvious improvement to prior art. "I did A with B using C by way of D"

2. In patent application, the patent editor tries to widen the claim to. "A with B using C", "A using C by way of D" or even all the way to the silly and obvious "A".

3. Patent examiner rejects most claims. Some widened claims, beyond what the inventor considered to be his invention, are accepted by the examiner because they really are novel and non-obvious. The patent is now more valuable too inventor (or, more often, his employer) because it covers more things.

This process of trying to extend the claims by making them more general is quite mechanical. Patent editors do it almost automatically and without really trying to think too hard if the result makes much sense.

Sometimes overworked examiners accept silly over-generalized claims on an application and it makes it into a granted patent. It is a serious problem with the system (or a win, if you are the submitting company). Such claims may be overturned later in court, but most patent lawsuits are settled out of court, never challenging such claims because of the costs and risks involved. This makes such over generalized patents a weapon for bullies.

Sometimes, if you are a high-profile company that is under the public eye, people will pick such unexamined claims in a patent application and make them into a silly headline "company X tries to patent obvious thing Y!!!".

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.

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