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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in the centimeter-gram-second (CGS) system as equal to 100 ergs of energy absorbed by one gram of matter, the rad was superseded by the "gray," an SI unit where 100 rad are equal to one gray.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 ?
During RAD therapy, the replacement of the ultrafiltrate lost in CVVH is administered by a postdilution method because a predilution replacement fluid is infused pre-hemofilter, causing some of it to be filtered into the ultrafiltrate, thus changing its composition.
When the patient is ready for RAD therapy and all consents are signed, the RAD is brought to the bedside.
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.
Japan represents the second largest economy in the world, and we are excited to join forces with Nippon RAD as a strategic partner," said Ron Baker, president and CEO, ETI.
Nippon RAD designs and develops business applications, middleware solutions, mainframe software, network security and information systems for customers in the financial services, manufacturing, pharmaceuticals and law enforcement industries, among others.
RAD will develop a circuit emulation "core" based on its key technologies, to be incorporated by Dallas Semiconductor, alongside its own integrated T1/E1/J1 transceiver technologies, into the ToP chips.
Although the Telephone Service of the Vatican State did not disclose the precise nature of their application, the RAD products that are deployed are typically used for purposes of service termination and demarcation.
Our goal is to create technology that will enable individual inventors and entrepreneurs to provide new services of value similar to large Internet services people use every day," said David Patterson, UC Berkeley professor of electrical engineering and computer sciences and founding director of the RAD Lab.
Working with RAD, Time Warner Cable has successfully positioned themselves as a strategic partner to their customers, not simply a vendor of bandwidth.
Egate provides a solution to service providers that need to map Ethernet over T1/E1 circuits and then hand the Ethernet traffic to the packet-switched backbone," explains Ramon Horkany, Egate Product Line Manager at RAD.
Ethernet in the Local Loop reduces carrier expenses, since Ethernet ports are far less expensive than other options," explains Yacov Cazes, Senior Product Line Manager at RAD Data Communications.