bernulli

12 ms·

151.
by bernulli 5y ago
You can compare the price of college textbooks to the price of textbooks for professionals and you will see there is no difference. It's simply a niche market. Personally, I prefer decade old textbooks, hardcover, beautifully typeset,
152.
by bernulli 5y ago
How is that a "kickback from the publishers for forcing these (always crap) textbooks on their students" ? I'm not denying that black sheep exist, I am denying a pervasive conspiracy of "big textbook" to the benefit
153.
by bernulli 5y ago
That's not really a thing. Also, wait till you hear how much an academic makes from the articles they publish, and from those lucrative research grants from big-[oil,pharma,etc].
154.
by bernulli 5y ago
Not gonna turn "bernulli's 9 rules for academic productivity" into a career, I promise!
155.
by bernulli 5y ago
Excellent advice here on tools. My biggest piece of advice, that resulted in my biggest push of productivity, was a daily routine tailored to how your performance varies over the day. For me (1) sitting down and writing (anything: paper, th
156.
by bernulli 5y ago
This makes no sense whatsoever, maybe the abyss has stared back? Turbulent flows can be quite predictable, as the fluctuations smooth out statistically. Even simple turbulence models are quite accurate when it comes to the effect of turbule
157.
by bernulli 5y ago
That's a great question and indeed a full research direction -- uncertainty quantification. Unfortunately it turns out that it's not that simple.
158.
by bernulli 5y ago
I'm not solving anything and I did not bring turbulence into this. Parent wrote that the Tesla valve harnesses turbulence to function, I gave a counterexample of how Tesla valves are applied for laminar microflows, ergo turbulence cann
159.
by bernulli 5y ago
But the limits to these transformations are governed by the 2nd law of thermodynamics, not the first. You can't arbitrarily convert heat into other forms of energy. E.g., if your machine relies on all energy in my room to spontaneously
160.
by bernulli 5y ago
It's really not, though. It wouldn't work in laminar micro fluid applications otherwise.
161.
by bernulli 5y ago
It's very easy. Mind you that 'simulation' means you're trying to solve a system of partial differential equations at tens of thousands to billions of positions simultaneously. The simple truth is that computational flui
162.
by bernulli 5y ago
It's really not for almost all encounters we will ever have with it. In fact, you can model even air (or other gases) as incompressible as long as the Mach number is <0.3 with really good accuracy.
163.
by bernulli 5y ago
They run on temperature differences, that's how you get usable energy out of it. Google Carnot engine, there's even a super simple way to find the maximum efficiency just from the temperatures!
164.
by bernulli 5y ago
People are downvoting because billpg essentially wants a perpetuum mobile, something that creates useable energy just from the presence of a high temperature reservoir. This violates the 2nd law of thermodynamics. Heat does not equal usable
165.
by bernulli 5y ago
I think it's a bit late for foresight, maybe Cassandra (is there a Norse equivalent?) is a more apt description of the situation we are in ;-) Good luck, great idea, hope it works out!
166.
by bernulli 5y ago
Exactly. Which is more than what Gagarin or Shepard did. Sure, McAuliffe trained to do so much more, but all of them fulfill the criterion you gave of what an astronaut is.
167.
by bernulli 5y ago
Not that I’m a fan, but Malcolm Gladwell wrote a whole book (Outliers) about how this is not true.
168.
by bernulli 5y ago
Check out Prandtl's Boundary Layer Theory https://en.wikipedia.org/wiki/Boundary_layer It's a set of smart physical observations/assumptions that allow you to find closed form solutions for the Navier St
169.
by bernulli 5y ago
Is the static friction what is going on with wheels? Why do race cars (dragster, F1, etc) have wide, smooth (un-knobby) tires if it's so disadvantageous (no gain, but higher weight and moment of inertia)?
170.
by bernulli 5y ago
I wrote a python script that returns annotated PDFs of submitted homework via outlook to all students. My workflow is to grade on my iPad, Airdrop the files to my computer, then I can run the script that matches emails and PDFs and sends th
171.
by bernulli 5y ago
Not a unique German thing, I am afraid, https://en.wikipedia.org/wiki/Diesel_emissions_scandal "A practice by diesel vehicles including the Volvo S60, Renault's Espace Energy and the Jeep Renegade, exceeded
172.
by bernulli 5y ago
I understand what the author is claiming. What I am saying is that the argument does not show that at all: if, for the same action, you will be charged in country A (because of stricter hate crime laws) but not in country B, then, obviously
173.
by bernulli 5y ago
This is a weird article, as others pointed out. I found the part about hate speech and intolerance particularly nonsensical: (1) Western Europe has (more? stricter?) laws against hate speech than the U.S. (2) There are more cases of hate cr
174.
by bernulli 5y ago
'Dachshund' literally translates to badger-hound; they're bred to go down burrows and drive out badgers.
175.
by bernulli 5y ago
I don't know if you've ever looked into what goes on physically in the combustion chamber or even just the turbopumps? We are far away from having the physics identified, let alone the math figured out. E.g., combustion instabilit
176.
by bernulli 5y ago
But you also don't want your target to know that it is being attacked to prevent countermeasures.
177.
by bernulli 5y ago
The key point of hypersonic weapons is that they are maneuverable.
178.
by bernulli 5y ago
Surely the Isp, i.e. thrust per propellant weight flow rate, would have to be much higher for that air turborocket? 250s is not that great already for a rocket that has to carry all of the propellant; the big advantage of an airbreathing en
179.
by bernulli 5y ago
My favorite crazy ideas from Science are - "Imagine, they're like really small animals, but the're too small to see! The're everywhere! They live on us, in us, around us! They are what makes us sick!" (Pasteur, germ
180.
by bernulli 5y ago
Haha, fair enough. But what I mean is that the whole discussion in the article is about ink that still in its compartment inside the pen, prior to writing/drawing/etc. It has nowhere to go and cannot spread.

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