RI

RI or Ri may refer to:

Zodiac

In both astrology and historical astronomy, the zodiac (Greek: ζῳδιακός, zōidiakos) is a circle of twelve 30° divisions of celestial longitude that are centered upon the ecliptic, the apparent path of the Sun across the celestial sphere over the course of the year. The paths of the Moon and visible planets also remain close to the ecliptic, within the belt of the zodiac, which extends 8-9° north or south of the ecliptic, as measured in celestial latitude. Because the divisions are regular, they do not correspond exactly to the boundaries of the twelve constellations after which they are named.

Historically, these twelve divisions are called signs. Essentially, the zodiac is a celestial coordinate system, or more specifically an ecliptic coordinate system, which takes the ecliptic as the origin of latitude, and the position of the Sun at vernal equinox as the origin of longitude.

Usage

The zodiac was in use by the Roman era, based on concepts inherited by Hellenistic astronomy from Babylonian astronomy of the Chaldean period (mid-1st millennium BC), which, in turn, derived from an earlier system of lists of stars along the ecliptic. The construction of the zodiac is described in Ptolemy's vast 2nd century AD work, the Almagest.

R&I

R&I may refer to:

See also

R1

R1, R.I, R01 or R-1 may refer to:

Military equipment

Transport

Resistance to interrogation

R2I, RTI, or resistance to interrogation is a name for a set of techniques taught to UK troops, and other NATO soldiers with the express purpose of preparing them, after capture by the enemy, to resist interrogation techniques such as humiliation and torture.

The trainees undergo practices such as hooding, sleep deprivation, time disorientation, prolonged nakedness, sexual humiliation and deprivation of warmth, water and food. Many of these techniques are against international law if used in interrogations.

Standard RTI for most special military branches of American and European governments covers both tortures that are condemned by the United Nations and interrogation techniques that are considered legitimate, usually presented along a sliding scale. For instance, a soldier would be subjected to slight discomforts before being subjected to more torturous techniques.

RTI is a product of the market for military information, which has been in place since as early as when Sun Tzu wrote The Art of War. Especially moving into modern times, when information and technology is often more important than numbers in combat, and when torture has been used less often to humiliate and more often to extract information, RTI has become an integral part of military training in most Western countries in one way or another.

R4200

The R4200 is a microprocessor designed by MIPS Technologies, Inc. (MTI) that implemented the MIPS III instruction set architecture (ISA). It was also known as the VRX during development. The microprocessor was licensed to NEC, and the company fabricated and marketed it as the VR4200. The first VR4200, an 80 MHz part, was introduced in 1993. A faster 100 MHz part became available in 1994. The R4200 was developed specifically for low-power Windows NT computers such as personal computers and laptops. MTI claimed the microprocessor's integer performance was greater than that of a high-end Intel i486 and 80% of a P5-variant Pentium microprocessor. The R4200 ultimately did not see any use in personal computers and was repositioned as an embedded microprocessor that competed with the R4600. The R4300i variant was used in the widely popular Nintendo 64 video game console.

Description

The R4200 is a scalar design with a five-stage classic RISC pipeline. A notable feature is the use of the integer datapath for performing arithmetic operations on the mantissa portion of a floating point number. A separate datapath was used for the exponent. This scheme reduced cost by reducing the number of transistors, the size of the chip, and power consumption. It also impacted floating point performance negatively, but the R4200's intended applications did not require high floating point performance.