Turbo codes are a class of high-performance error correction codes used in digital communication and data storage systems. They were introduced in the early 1990s by Claude Berrou, Alain Glavieux, and Olivier Thitimajshima. Turbo codes are designed to approach the theoretical limits of error correction as defined by the Shannon limit, making them highly effective in ensuring reliable data transmission over noisy channels.
The Zyablov bound is a concept in the field of combinatorial design and coding theory, particularly related to covering designs. Named after the Russian mathematician Alexander Zyablov, the bound provides a limit on the number of blocks in a covering design given certain parameters. In more formal terms, the Zyablov bound applies to the problem of covering a finite set with subsets (or blocks) such that every element of the set is contained in at least a specified number of blocks.
As of my last knowledge update in October 2023, Jaan Sarv is not a widely recognized term in English or popular culture, and it may refer to something specific in a niche context, such as a name, a brand, a work of art, a character, or a term in a specific language or community.
"Foundations of Geometry" is a seminal work by the mathematician David Hilbert, published in 1899. In this book, Hilbert sought to establish a rigorous axiomatic framework for geometry, countering the more intuitive approaches that had been prevalent before him, particularly those based on the work of Euclid. In "Foundations of Geometry," Hilbert presented a set of axioms that form the basis for geometric reasoning.
Reflection groups are a type of mathematical structure that arise in the study of symmetries in geometry and algebra. More specifically, they are groups generated by reflections across hyperplanes in a Euclidean space. Here’s a more detailed breakdown: 1. **Definition**: A reflection group in \( \mathbb{R}^n \) is a group that can be generated by a finite set of reflections. Each reflection is an orthogonal transformation that flips points across a hyperplane.
The Cone Condition, often discussed in the context of optimization and mathematical programming, refers to certain structural properties of sets in a vector space, particularly in relation to conical sets and convexity. In more specific terms, the Cone Condition typically addresses whether a feasible region, defined by a set of constraints, satisfies certain properties that are conducive to finding solutions via optimization methods.
Euclid's "Optics" is a treatise attributed to the ancient Greek mathematician and philosopher Euclid, who is best known for his work in geometry. This work is one of the earliest known texts on the study of vision and light, focusing particularly on the properties of vision and the geometry of sight.
Euler's quadrilateral theorem states that for any convex quadrilateral, the sum of the lengths of the opposite sides is equal if and only if the quadrilateral is cyclic. A cyclic quadrilateral is one that can be inscribed in a circle, meaning all its vertices lie on the circumference of that circle. To put it more formally, for a convex quadrilateral \(ABCD\), if \(AB + CD = AD + BC\), then the quadrilateral \(ABCD\) is cyclic.
Gyration generally refers to a rotational movement or motion around an axis. The term is often used in various fields, including: 1. **Physics**: In the context of rotational dynamics, gyration can refer to the movement of particles or objects around a central point or axis. For example, the concept of the radius of gyration is used to describe the distribution of mass around an axis in a rigid body.
The Intercept Theorem, also known as the Basic Proportionality Theorem or Thales's theorem, states that if two parallel lines are intersected by two transversals, then the segments on the transversals are proportional. To be more precise, consider two parallel lines \( l_1 \) and \( l_2 \) cut by two transversals (lines) \( t_1 \) and \( t_2 \) that intersect them.
A **plane curve** is a curve that lies entirely within a single plane. In mathematical terms, a plane curve can be described using a set of parametric equations, a single equation in two variables (typically \(x\) and \(y\)), or in polar coordinates.
Van Schooten's theorem is a result in geometry that deals with the properties of cyclic quadrilaterals. It states that for any cyclic quadrilateral (a four-sided figure whose vertices all lie on a single circle), the lengths of the segments connecting the midpoints of opposite sides are equal to half the lengths of the diagonals of the quadrilateral.
Arithmetic problems in plane geometry typically involve calculations and problem-solving related to shapes, figures, and their properties in two-dimensional space. These problems often require the use of basic arithmetic, algebra, and geometric principles to find unknown lengths, areas, perimeters, and angles. Here’s a brief overview of common types of arithmetic problems in plane geometry: 1. **Calculating Area**: Problems may involve finding the area of different shapes, such as triangles, rectangles, circles, and polygons.
Compass and straightedge constructions refer to a classical method of drawing geometric figures using only two tools: a compass and a straightedge (a ruler without markings). This method has its roots in ancient Greek geometry and is foundational for various geometric principles and theorems. ### Tools Explained: 1. **Compass**: A tool used to draw arcs or circles and to measure distances. It can set off equal distances (like the radius of a circle) when one point is placed at a specific location.
A Gabriel Graph is a type of geometric graph that is defined based on a spatial configuration of points. It is constructed from a set of points in a Euclidean space, and it has the following property: an edge is drawn between two points \(A\) and \(B\) if and only if the disk whose diameter is the segment \(AB\) contains no other points from the set.
Dual quaternions are an extension of quaternions that can be used to represent rigid transformations in 3D space, such as rotations and translations. However, their applications can also extend to 2D geometry, especially in the context of computer graphics, robotics, and animation.
Menelaus's theorem is a fundamental result in geometry, specifically in the study of triangles and transversals. It relates to the collinearity of points defined by a triangle and a line that intersects its sides.
Pappus's area theorem, also known as Pappus's centroid theorem, is a fundamental result in geometry concerning the surface area of a solid of revolution. The theorem states that the surface area \( A \) of a solid formed by revolving a plane figure about an external axis (that is not intersecting the figure) is equal to the product of the length of the path traced by the centroid of the figure and the area of the figure itself.
Cyclone Xaver, also known as Storm Xaver, was a powerful extratropical cyclone that impacted parts of Northern Europe in early December 2013. It brought severe weather conditions, including strong winds, heavy rainfall, and storm surges, particularly to the UK, Germany, and the Netherlands. The storm caused significant disruption, including flooding, damage to infrastructure, and power outages, affecting thousands of homes.
The "Power of a Point" theorem is a fundamental concept in geometry, particularly in the study of circles. It provides a relationship between the distances from a point to a circle and various segments created by lines related to that circle.

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