Installation in a Christian liturgical act that formally inducts an incumbent into a new role in a particularl place such as a cathedral. The term arises from the act of symbolically leading the incumbent to their stall within the cathedral or other place of worship. Within the Anglican tradition it is commonly used when inaugurating a new Dean or Canon.
Installation art is an artistic genre of three-dimensional works that often are site-specific and designed to transform the perception of a space. Generally, the term is applied to interior spaces, whereas exterior interventions are often called public art, land art or intervention art; however, the boundaries between these terms overlap.
Installation art can be either temporary or permanent. Installation artworks have been constructed in exhibition spaces such as museums and galleries, as well as public and private spaces. The genre incorporates a broad range of everyday and natural materials, which are often chosen for their "evocative" qualities, as well as new media such as video, sound, performance, immersive virtual reality and the internet. Many installations are site-specific in that they are designed to exist only in the space for which they were created, appealing to qualities evident in a three-dimensional immersive medium. Artistic collectives such as the Exhibition Lab at New York's American Museum of Natural History created environments to showcase the natural world in as realistic a medium as possible. Likewise, Walt Disney Imagineering employed a similar philosophy when designing the multiple immersive spaces for Disneyland in 1955. Since its acceptance as a separate discipline, a number of institutions focusing on Installation art were created. These included the Mattress Factory, Pittsburgh, the Museum of Installation in London, and the Fairy Doors of Ann Arbor, MI, among others.
The development of the Reduce computer algebra system was started in the 1960s by Anthony C. Hearn. Since then, many scientists from all over the world have contributed to its development under his direction.
Reduce is written entirely in its own LISP dialect called Portable Standard LISP, expressed in an Algol-like syntax called RLISP. The latter is used as a basis for Reduce's user-level language.
Intuitively, problem A is reducible to problem B if an algorithm for solving problem B efficiently (if it existed) could also be used as a subroutine to solve problem A efficiently. When this is true, solving A cannot be harder than solving B. "Harder" means having a higher estimate of the required computational resources in a given context (e.g., higher time complexity, etc.).
We write A ≤m B, usually with a subscript on the ≤ to indicate the type of reduction being used (m: mapping reduction, p: polynomial reduction).