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a former unit of absorbed ionizing radiation dose equivalent to an energy absorption per unit mass of 0.01 joule per kilogram of irradiated material. 1 rad is equivalent to 0.01 gray



a subsidiary unit of absorbed radiation dose. It is applied to any kind of ionizing radiation and corresponds to a radiant energy of 100 ergs absorbed by 1 g of a substance: 1 rad = 2.388 × 10–6 = 0.01 joule per kg.


A special unit of absorbed dose, equal to energy absorption of 100 ergs per gram (0.01 joule per kilogram); equal to 0.01 gray.


A heating unit usually exposed to view within the room or space to be heated; transfers heat by radiation to objects within visible range, and by conduction to the surrounding air, which in turn is circulated by natural convection; usually fed by steam or hot water.




(1) (Rapid Application Development) Developing systems incrementally and delivering working pieces every three to four months, rather than waiting until the entire project is programmed before implementing it. Over the years, many information projects have failed, because, by the time the implementation took place, the business had changed.

RAD employs a variety of automated design and development tools, including CASE, 4GLs, visual programming and GUI builders, all of which help create prototypes and running applications faster than by coding program statements a line at a time. The term was coined years ago by industry guru James Martin and focuses on personnel management and user involvement as much as on technology. Joint application development is another RAD concept (see JAD).

The term is also used in a more general way to refer to an environment that produces applications quickly and efficiently.

(2) (RADiation dose) An earlier unit of measurement of absorbed radiation. Defined in the centimeter-gram-second (CGS) system as equal to 100 ergs of energy absorbed by one gram of matter, the rad was superseded by the "gray," an SI unit where 100 rad are equal to one gray. See radiation hardened and gray.
References in periodicals archive ?
RAD will exhibit the new solution at CIGRE 2014, the international forum for electrical innovations, which opens in Paris August 24.
Founded in 1981, RAD Data Communications has achieved international recognition as a major manufacturer of high quality access and backhaul equipment for data communications and telecommunications applications.
Wallis explained the evolving RAD curriculum and methodology in her pedagogical analysis of technical exercises and components in a ballet class.
Because the competition is open only to students who are registered at accredited institutions of higher education, RAD requests that a representative of an appropriate academic department assume responsibility for submissions from that institution and contact Dr.
In the past several quarters RAD has experienced a growth in demand for its advanced communication solutions.
Please see CodeGear release titled, "CodeGear Introduces Delphi for Win32 Providing RAD Development for Windows Vista and AJAX.
RAD will also continue to offer, free of charge, one full year of basic support, including business-hours telephone support and free software updates - under its RADcare Maintenance Services program.
In 1995, at the RAD's thirty-first summer school, such luminaries of the British ballet world as Pamela May, Julia Farron, Anthony Dowson and the new artistic director of the RAD, Lynn Wallis, all taught classes.
For the first time, RAD is showing at SunWorld (booth #1338) PowerMedia presentations and home pages that incorporate Java-scripted applications or "Applets.
TDM pseudowire technology, developed and pioneered by RAD, is an evolutionary approach for transporting circuit-switched telephony and legacy data over IP and Gigabit Ethernet networks," explains Jacky Acoca, Business Development Manager at RAD Data Communications.
Not only has RAD virtually halved its debt to [pound]620,000 (approximately $935,000), with hopes of eradicating the debt completely within two years, but also its membership has increased by three percent, to 17,023 teachers, and the entries for its grade examinations are up by thirty-three percent worldwide.
Beahn have been elected as additional directors of Rad San, Inc.