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infinet
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- infinetOnce I used an old MIPS debian in qemu to test big endian. I thought since LoongArch has its root in MIPS it may be big endian. It turns out "LoongArch bit designations are always little-endian".
- Documentation https://pkuhpc.github.io/CraneSched/en/index.html
- One reason is to use the Linux page cache instead of dedicating RAM to ZFS, given how expensive memory is now. I am very happy with MGLRU and won't miss ZFS's ARC.
- > to make this in an area with less infrastructure you might use a template and carbide gas torch to cut
Metal work seems very expensive in some places. In a 2025 paper [1], a cooking pot looks like several aluminium rings welded together, about 50 cm tall and 70 cm in diameter, is 416 USD in Ghana, which is one of the destinations of this hand-crank washing machine.
1. https://www.sciencedirect.com/science/article/pii/S266711312...
- Sticking head into a barbecue oven for 10 minutes might get rid of lice, but expecting cooking smoke kill bugs is absurd. People use the three stone and hearth fire not because they want the smoke, but because they do not know better. Combustion is a complicated process, it generates CO2, H20, CO, H2, CH4. The higher the temperature, the more thorough the burning. It requires the right amount of air, enough to burn all the biomass, but not too much that carries heat away thus lowers the temperature. Higher temperature also transfer heat more efficiently to the cookware. Only a well designed stove can do that. These are not things that can be figured by meditating in front of an open fire.
Saving fuel is a matter of life and death in the ancient world. Winter is brutal to the poor largely because gathering fuel is difficult, especially in areas that have supported large population for centuries.
- I am interested in unit cost for mass production. It needs to be significantly cheaper than an old style top-loading washing machine to be affordable. The design of old style washing machine is mature and priced at around $100 for 8kg model. I suspect it can be stripped down further, remove water pump, remove program controlled inlet valve et al. to reduce the cost to below $50. Granted, washing machine like that needs electricity, but solar panel may be cheap enough.
One more thing, the water is not always easy to get in poor places. It is often much easier to carry laundry to a well, creak, or river than transport water to home. The path to the water sources may be a narrow trail often going up and down hills, so even with wheels on the machine, it is impractical to drag the machine to the water.
- > the worst case is that we would have to ditch the space station (which is already planned in a few years)
There is more than one Space Station up there. "Tianhe space station module conducted preventive collision avoidance due to close approaches by the Starlink-1095 (2020-001BK) and Starlink-2305 (2021-024N) satellites on July 1 and Oct. 21 respectively." [1]. Wikipedia also has a long list of planned and proposed space stations.
1. https://www.n2yo.com/satellite-news/Chinas-space-station-man...
- My apologies for the digression. But it reminds me a post I saw long time ago when a guy installed all the antivirus/antimalware software he could find on a Windows machine. It started an antivirus civil war and the Windows fell into a coma within seconds.
- I'd love to know more about Unicycling. Is it just my browser, or is anyone else seeing the huge black Q letter or magnifying glass icon that occupies 2/3 of the screen?
- The article talks about fungi been attracted to ionising radiation. Per wikipedia:
https://en.wikipedia.org/wiki/Ionizing_radiation
Ionizing (or ionising) radiation is particle or photon that has enough energy to detaching electron from atoms or molecules. It includes all the usual high energy radiations such as Gamma, X-rays, high energy UV, alpha, beta, neutron et al. HN high energy physicists can correct me, sounds like it is not any particular category of the harmful radiation from a nuclear disaster, it is all of them.
- There were similar comments on HN. The argument goes that since it takes energy to produce PV panels and wind turbines, China effectively is an energy exporting country. What’s even better is some of the PV and turbines are produced with renewable energy. And unlike oil and gas, which are used only once, PV panels and wind turbines generate power for many years.
- That traditional biomass stove in paper's figures is perhaps the worst stove imaginable. Its efficiency could below 10%. Better designed stove has efficiency above 30% and has much less indoor air pollution.
That being said, the more I read it, the more I like this PV steam cooker. It is simple and easy to scale up by adding more PV panels and more sands. Although Ghana is close to the equator, I wonder whether it worth to steer the PV panels during the day.
Edit, efficiency measured by energy transferred to boiling water or cooking vs energy released from burning biomass.
- I used LLM to rewrite above comment to make it sounds less negative. Then I read those two chapters again. This book adds complexities to simple concepts. There are good math books for non-math majors, but this isn't one of them.
- Another JPEG XR user is Zeiss. It saves both grayscale and color microscope images with JPEG XR compression in a container format. Zeiss also released a C++ library (libczi) using the reference JPEG XR implementation to read/write these images. Somehow Zeiss is moving away from JPEG XR - its newer version of microscope control software saves with zstd compression by default.
- Agreed.
I really appreciate author’s effort and for releasing the PDF to the public. There are however areas I think could be made more helpful.
In the chapter on Trigonometric Functions, it begins with discussion of the derivative of the exponential function is itself, and then moves on to define sine and cosine via second degree derivatives. While interesting, this may not be the most helpful approach for intended readers.
The following chapter on Taylor Series also starts with a long discussion about the value of e. It is interesting, but it can feel a bit distracted from the main topic. The treatment of Taylor polynomials might benefit from a different approach similar to other texts.