The term "centroid" can refer to different concepts depending on the context, but generally, it denotes a point that represents the center or average of a geometric shape or a set of points. Here are a few contexts where centroids are commonly used: 1. **Geometry**: In a geometric shape (like a triangle, rectangle, or polygon), the centroid is the point where all the medians intersect.
The term "liquid whistle" is not widely recognized, and its meaning may vary depending on the context in which it is used. Here are a few possibilities: 1. **Whistle Made from Liquid**: It could refer to a type of musical instrument or sound-producing device that generates sound through the manipulation of liquid, such as a water whistle or a similar instrument that uses water to create sound.
Unwin Radar is a supply chain management solution designed to help businesses optimize their inventory, forecast demand, and enhance overall operational efficiency. It leverages advanced analytics, machine learning, and real-time data to help organizations make informed decisions regarding inventory management and supply chain operations. Key features typically associated with solutions like Unwin Radar include: 1. **Demand Forecasting**: Predicting future demand for products to help maintain optimal inventory levels.
Manhattan Project by Ciro Santilli 40 Updated 2025-07-16
Video 1.
Historic, unique Manhattan Project footage from Los Alamos by Los Alamos National Lab
. Source.
Mostly the daily life part of things, but very good, includes subtitles explaining the people and places shown.
Marked with identifier "LA-UR 11-4449".
Josephson equations by Ciro Santilli 40 Updated 2025-07-16
Two equations derived from first principles by Brian Josephson that characterize the device, somewhat like an I-V curve:
where:
Note how these equations are not a typical I-V curve, as they are not an instantaneous dependency between voltage and current: the history of the voltage matters! Or in other words, the system has an internal state, represented by the Josephson phase at a given point in time.
To understand them better, it is important to look at some important cases separately:

Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
    Figure 1.
    Screenshot of the "Derivative" topic page
    . View it live at: ourbigbook.com/go/topic/derivative
  2. local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
    This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
    Figure 2.
    You can publish local OurBigBook lightweight markup files to either https://OurBigBook.com or as a static website
    .
    Figure 3.
    Visual Studio Code extension installation
    .
    Figure 4.
    Visual Studio Code extension tree navigation
    .
    Figure 5.
    Web editor
    . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
    Video 4.
    OurBigBook Visual Studio Code extension editing and navigation demo
    . Source.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact