Solid geometry

In mathematics, solid geometry is the traditional name for the geometry of three-dimensional Euclidean space.

Stereometry deals with the measurements of volumes of various solid figures or Polyhedrons (three-dimensional figures) including pyramids, cylinders, cones, truncated cones, spheres, and prisms.

The Pythagoreans dealt with the regular solids, but the pyramid, prism, cone and cylinder were not studied until the Platonists. Eudoxus established their measurement, proving the pyramid and cone to have one-third the volume of a prism and cylinder on the same base and of the same height, and was probably the discoverer of a proof that the volume of a sphere is proportional to the cube of its radius.

Basic topics of solid geometry

Basic topics are:

SOLID (object-oriented design)

In computer programming, SOLID (Single responsibility, Open-closed, Liskov substitution, Interface segregation and Dependency inversion) is a mnemonic acronym introduced by Michael Feathers for the "first five principles" named by Robert C. Martin in the early 2000s that stands for five basic principles of object-oriented programming and design. The principles, when applied together, intend to make it more likely that a programmer will create a system that is easy to maintain and extend over time. The principles of SOLID are guidelines that can be applied while working on software to remove code smells by causing the programmer to refactor the software's source code until it is both legible and extensible. It is part of an overall strategy of agile and Adaptive Software Development.

Overview

See also

Basic concepts and related topics

Earth (Jefferson Starship album)

Earth is a 1978 album by Jefferson Starship. The album was recorded in 1977, with the same band lineup as the previous album, Spitfire. The band had not toured in 1977, partly due to Marty Balin's reluctance to commit fully to the band. The song "Count on Me" became a Top-10 single, peaking at #8. The album itself hit #5 on the Billboard charts. A US and European tour followed which resulted in an audience riot in Germany after the band decided not to play without Grace Slick who was ill. They lost all their guitars and equipment during the riot and played one more tense show on German TV in Hamburg after which Grace left the band for one album. Marty Balin fronted the band for one more show at a Genesis concert at the Knebworth Festival in England using rented equipment. When they returned to the USA drummer John Barbata left the band after a serious car accident. This would be the end of the 1970s line-up and several new members joined the band, as well as a new record producer. Success of this album led to Jefferson Starship being contacted to provide a song for the Star Wars Holiday Special.

Earth (Wu Xing)

Earth (Chinese: 土; pinyin: tǔ), is the changing point of the matter. Earth is the third element in the Wu Xing cycle.

Earth is a balance of both yin and yang, the feminine and masculine together. Its motion is inward and centering, and its energy is stabilizing and conserving. It is associated with the color yellow and the planet Saturn, and it lies at the center of the compass in the Chinese cosmos. It is associated with the turn of each of the four seasons and with damp. It governs the Spleen, Stomach, mouth and muscles. Its negative emotion is anxiety and its positive emotion is empathy. Its Primal Spirit is represented by the Yellow Dragon. Colour Yellow, Golden (Sun).

Attributes

The Chinese think Earth is associated with the qualities of patience, thoughtfulness, practicality, hard work, and stability. The earth element is also nurturing and seeks to draw all things together with itself, in order to bring harmony, rootedness and stability. Other attributes of the earth element include ambition, stubbornness, responsibility and long-term planning.

List of Foundation universe planets

This is a list of Foundation universe planets featured or mentioned in the Robot series, Empire series, and Foundation series created by Isaac Asimov.

61 Cygni

The star system 61 Cygni, in the Sirius Sector, is advanced by Lord Dorwin as the potential site for a planet of origin for the human species. Lord Dorwin cites 'Sol' (meaning Earth's Sun) and three other planetary systems in the Sirius Sector, along with Arcturus in the Arcturus Sector, as potential original worlds. (This fact seems to be contradicted by information given in Foundation and Earth). Claims were made as early as 1942 that 61 Cygni had a planetary system, though to date, none has been verified, and Asimov was aware of these claims.

Alpha

Alpha is a fictional planet orbiting the larger of the two stars in the Alpha Centauri system.

In Asimov's Foundation Series, Alpha Centauri is cited by Lord Dorwin as one of the solar systems where humankind potentially originated. The others are Sol, Sirius, 61 Cygni and Arcturus. Beyond mentioning that it is in the Sirius Sector, Dorwin gives no further details.