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bunje

81 karma · joined June 27, 2019

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bunje··on Texas repeatedly raises pollution limits for Cheniere LNG plant
How quickly do you think stopping the sanctions would bring the energy prices down? Russia already stopped gas exports to several countries.
bunje··on Integer vs. Linear Programming in Python
In university I learned about the simplex method which can be applied to linear programming. I don't know if it's used by modern solvers.
bunje··on Ask HN: Developers who switched careers, what are you doing now?
I did software engineering for 3 years after graduation. Now I teach mathematics in a high school since '20. Software engineering was very stressful for me and I also wanted to sync holidays with my kids. Parents seem to value my background. Pay is low but I have a reasonable amount of extra time to tinker.
bunje··on Why isn't there a replication crisis in math?
"Mathematics is the part of physics where experiments are cheap." - V.I. Arnold
bunje··on Robotics 501: Mathematics for Robotics
QR factorization is cool because it is part of QR iteration and you can use it to find all zeros of a polynomial at once.
bunje··on Supersonic Trebuchet
Solutions to differential equations belong to infinite dimensional function spaces unless discretized.
bunje··on Deaths involving Covid-19 by vaccination status, England
I don't understand, there were over 50k non-covid deaths in the twice vaccinated and around 500 covid deaths. That sounds significant, or is it due to the age distribution of twice vaccinated?
bunje··on Sci-Hub is fundraising
I think in the past journals prohibiting the use of preprint archives was more common.
bunje··on Dark Matter: The Situation Has Changed
How are the theories incompatible? My basic understanding is that GR describes how the space looks like and Standard Model describes fields defined in this space.
bunje··on Beyond Meat’s Beyond Burger life cycle assessment (2018)
Colon cancer risk is increased by 28% due to excessive consumption of red meat.
bunje··on France cuts two nuclear-powered submarines in half to make one new one
I would guess that it is much more dangerous to modify a modern car because they utilize nontrivial shell geometry to improve the rigidity or to reduce weight. When I was attending driving lessons, my teacher claimed that the specific shape of the windscreen or rear window was a very important safety feature in the scenario that the car rolls over.
bunje··on Galerkin Approximation
I think variational problems are more naturally understood through energy minimization. You start with the energy of the system and try to minimize it via derivatives. Then you arrive at a variational problem. The differential equation is then more of an afterthought.
bunje··on Galerkin Approximation
Finite differences are simple in cubes and domains that can be mapped to one. Not so much in an arbitrary tetrahedral mesh.
bunje··on Manim – an animation engine for explanatory math videos
As a teacher, I'd like to use this in presentation slides, i.e. pause the output at specific times and continue only after a button is pressed. Does anyone know if there exists a tool, e.g., to automatically pause MP4 playback at specific times?
bunje··on Jair Bolsonaro: Organized Crime and Corruption 2020 Person of the Year
I cannot understand what you are implying. Can you be more specific?
bunje··on A ubiquitous tire rubber–derived chemical induces acute mortality in coho salmon
Why is that?
bunje··on Less than half of Americans know that alcohol is a carcinogen
I checked some of the references at CDC web page and seems that I won't die any time soon drinking one beer a day (male, non-smoker). E.g., https://pubmed.ncbi.nlm.nih.gov/26286216/
bunje··on The Most Common Errors in Undergraduate Mathematics (2009)
So you say we should specify when 2 means number two and when it means the constant function? How does it help?
bunje··on Tiny bubbles under a ship may help reduce fuel consumption
I've analyzed performance data from air lubrication vessels with some retrofits included. Frankly, never witnessed over 5% gain. At specific velocity range the gain could be 5% on average if the installation has been really successful. They might be better nowadays.
bunje··on JuliaMono – a monospaced font for scientific and technical computing
So you need a special editor to write code in Julia?
bunje··on PyPy 7.3.2 triple release: Python 2.7, 3.6, and 3.7
Currently my greatest concern is the inability of Julia to provide stability even after they've reached 1.0. On paper 1.0 is a LTS release and still supported, but how many packages actually support it anymore? There seems to be no guidelines either, the official stance is that "we move on and drop LTS when the package developers move on."
bunje··on How close are computers to automating mathematical reasoning?
Yes, I agree. As a mathematician, I spend lots of time trying to find the correct definitions with only a rough idea what I'm trying to prove (the theorem).
bunje··on I Just Hit $100k/year On GitHub Sponsors
You can accept a gift. It's also possible for someone to give a grant. But I'm not sure how they would work out in case of open source. I know that people write books using a grant.
bunje··on Amazon refuses to sell book on Covid-19 and lockdowns
Again, I'm not questioning that. Mathematically, does "tell people to use masks" imply "less new cases"? E.g., what if people decide to spend 5x more time with other people on average due to a mask requirement making them feel safe? That could easily cause more cases.
bunje··on Amazon refuses to sell book on Covid-19 and lockdowns
It's explained in point two. We're talking about large quantities of people here. Technically mask blocks droplets. But if you tell everyone to use a mask, does it reduce transmission on average?
bunje··on A Git Repo to Document Police Brutality During the 2020 George Floyd Protests
This was really interesting: https://m.youtube.com/watch?v=isPkpZehssY
bunje··on DIY Particle Detector
I once did an experiment with a rock containing uranium and a Geiger counter. The noise stopped immediately after putting printing paper between them and resumed after taking it off.
bunje··on Automating Complex 3D Modeling
I have not so far heard any compelling arguments for using other than tetrahedral or hexahedral meshes in finite element computations. I know that there is a lot of research going on but the motivation is not clear to me.

Error estimates are dependent on the polynomial degree and the average cell size, and not the "amount of corners per cell" or anything like that.

bunje··on A New Problem Is Brewing in the Beer Industry: One Million Kegs Are Going Stale
I've heard this can cause methanol blindness and increase in black market but who knows. Soon we will learn.
bunje··on Instacart announces new Covid-19 policies and plans to hire 250k more shoppers
I've been receiving the influenza vaccination every year. It wouldn't be a huge problem to receive also SARS-CoV-2 vaccination on top of that. Also at some point my kid received Rota-virus vaccinations every 3-6 months. It would be a hassle to inject everyone but doable in a country with modern medical system.
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