Basically this plot is why. Efficiency versus speed characteristics due to aerodynamics of propellors versus cowled rotors. Turboprop for short low flights, high bypass turbofan for long and high flights.
That's interesting. Unclipping the rail is a bit of an exercise though. Makes sense that it must be in tension, otherwise it would move on unclipping. I guess they just measure it in the morning. All these types of devices are less practical as soon as you have to disrupt services to do the measurement.
Your idea of the measuring the dynamic response is something that has been investigated. Modal testing is very common (using accelerometers on the rail and a force measuring hammer). The effect would depend on the boundary conditions of the rail (so basically something that varies from site to site) so you would need to track how it changes over time. The engineering problem is how to collect this data easily.
Part of the problem is that even the state of stress at installation isn't known very precisely. I basically did some pre work on a similar idea. Working through if you could track the displacement of sleepers could you figure it out. Problem is the extension in nominal range is linear and there isn't a simple way to work out where zero is.
I've only found mentions online about spraying post buckling during repairs, but pre-emptive spraying does (did) occur. You will hear about speed restrictions on hot days to avoid buckling.
Buckling at high temperature is better than fracture at low temperatures. I used to do research in this area. The "holy grail" technology would be a non destructive way to infer the "neutral stress temperature" of continuously welded rail that has been already installed in a quick and non destructive way. Saw lots of weird hopeful technology prototypes based of measuring the hysteresis curves of induced magnetism in the rail, idea being that the stress would have some effect on the magnetic domains. Never worked in the field AFAIK.
Here in Australia they will get hoses out on hot days desperately trying to cool the rail down to stop it buckling.
I think if you did parse the sentiment of citations you would get something quite bland, like 90% are very neutral (i.e. the effect of X on Y has been investigated in A, B, and C).
The cynic in me would say that this is because a lot of these type of citations are a defence against getting A, B, or C as a reviewer, or even worse the citation was inserted on review to make A, B or C happy because they were the reviewer and went shamelessly fishing for citations.
Also what is the purchase price difference between the these two cars (the malibu versus the hummer)? I'm not American so not really familiar with either but from what I know I assume the average person who would but the ev wouldn't be cross shopping for the malibu. It seems like a bit of a straw man to present the figures for these two cars. It would be better to have what the average model 3 buyer would have otherwise purchased.
Have to be under 40 too, so it isn't really an equivalent to the Nobel. Maths culture is weird though, long held belief that it is a young person's game.
Athletes aren't a great example. A quick look at the literature and you will quickly find heaps of studies on eating disorders in athletes. There are obvious and not so obvious motivations (i.e. a boxer making a weight division vs body image concerns). The big confounding factor in athletes is that they usually have extremely high discipline/self control.
If you can lower the transmembrane pressure you will get less output for less power and no fouling of the membrane. The economics of consumer choice drive design towards higher outputs and fouling.
This idea that you need to model GR to do GNSS is very over stated. You need to correct for a GR effect, but it is a small part of a residual in a least squares problem that gets regressed away. So it is important for understanding the error budget but it really is a small effect, compared to say ionospheric delay due to atmospheric charge or clock drift.
I'd like to see a comparison with a dumb as a box of hammers controller like PI or extremum seeking on the local gradient. I can't imagine that it is learning much more than a simple strategy like this, but maybe that's my lack of imagination...
It's really just a floating point precision issue. Even if you represented the input matrix as a rational elementary type the output eigenvalues would be a subset of the reals and calculated as being floating point.
You could get around it if you had a special matrix type where you knew you were definitely going to get rational eigenvalues and you could dispatch on that type.
Fractional quantum hall effect is a massive one. All the action is in condensed matter. Somehow less newsworthy despite being closer to practical applications than high energy physics.
That was really shocking for me the first time I went to China and watched their version on state sponsored television, around 2005. The contrast between the doom version of the news back home, to china's overly positive "15 people are missing in a coal mine but we are trying our darnedest to get them out" was really confronting. Made me realise that it has entertainment/manipulation as a goal, not providing information.
I love the book, but it is like the apogee of McCarthy idiosyncrasy. Obsessive about guns and death and has a complete absence of women. But it is beautiful for what it is.
I think most musicians recognise that the implicit rules are so complex that any reductive approach is going to fail if you want something like a simple formula for generating interesting music. It's just like language.
"Science is what we understand well enough to explain to a computer. Art is everything else we do."
There is nothing wrong with trying to turn an art into a science. Music just has a bunch of implicit rules that people want to make explicit. Musicians find this frustrating because they aren't interested in understanding music this way. Both perspectives are fine.
Navier stokes are incredibly important pdes for science and engineering, yet proof of even the existence of solutions is not currently available. Numerical methods are far more important than analytical solutions.
Off road the trade-off for me has always been "how quickly can I bail when things go wrong?". With spiky flats and sticky shoes I don't really have any problems with making enough power.
No data other than anecdotal but totally agree. I use flats on my road bike and look like an idiot but I go just as fast. I prefer to be able to wear normal shoes so I have less to carry. The whole "you can push while you pull" thing makes no sense, my quads are way more powerful than my hamstrings and you never need that much force when pedalling anyway, cardio fitness is always the limiting factor for me, not leg strength/power.