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[...]... transactions Durability A process of guaranteeing the system state changes ofa transaction are involatile, and impervious to total or partial system failures (See Server and Transaction.) Acknowledge A message in an OO (Object Orientated) system that verifies a state, and may be passed between client and server objects that may perhaps confirm that a client is able to receive a series of packets or messages... important to note that 3-D images can also be stored using 2-D vector matrices that include X and Y dimensions only Graphics transformation algorithms may be written in appropriate high level languages such as C++, Java and Visual Basic, and even in machine code or assembly language Any high-level programming language that supports arrays may be used to develop graphics transformation software However, APIs... Accelerator 1 A graphics card offering high-speed operation and optimised for GUIs like X-Windows, Windows and OS/2 (See 3-D and Graphics card.) 2 A video accelerator is a graphics card that is able to speed up the playback frame rate of video sequences The acceleration may be achieved by inserting duplicate frames, though today the challenge is to playback video at the capture frame rate rather than artificially... perspective of DVD and CDROM average access time is a measure of the time taken for the laser head to locate and begin reading an appropriate region of disc Access time tends to increase with turns of track that are farthest from the disc’s centre (See CD-ROM, DVD and Hard disc.) Account number A unique number that identifies an account held at a financial institution such as a bank or credit card company It...NUMERALS AND SYMBOLS & An ampersand symbol used as a prefix in the hexadecimal counting system * A wildcard that may be used as a substitute for an undefined series of characters in a search string .COM A domain category that generally signifies a commercial enterprise .JPG An extension for JPEG files (See DCT and JPEG.) NET A Microsoft initiative and strategy for OOP-based development tools and languages... UMTSes offer broadband user data rates and operate in the K-band (10.9– 36 GHz) and L-band (1.6–2.1 GHz) Aeronautical and maritime telecommunications were catalysts in the development and deployment of satellite mobile telephone services with the first maritime satellite launched in 1976 Called MARISAT it consisted of three geostationary satellites and was used by the US Navy This later evolved into the... telephone company and the ISP 56.6 Kbps modems are asymmetrical offering wider downstream bandwidths, so downloading times are shorter than those of uploading The ITU has attempted to amalgamate two the industry standards: • X2 • K56flex The resulting V.90 standard was specified provisionally and finally released in 1998 (See Access technologyand Modem.) 64 Kbps A data transfer rate offered by a single ISDN... frequency band and was also used in South America, Far East, and in the Asia Pacific region including Australia and New Zealand In the Asia Pacific country of Japan, NTT’s MCS system was the first commercial delivery ofa mobile 1G Japanese network While most first-world countries are closing 1G networks, many Less Developed Countries (LDCs) are actively investing in, and upgrading, them (See 2.5G, 3G, GPRS and. .. INMARISAT (International Maritime Satellite Organization) that provide public telecommunications services to airliners 3G Layers A 3G network consists of layers dedicated to: • Transport – carries data (bits) over the IP backbone and wireless access network that may be ATM, SONET or an alternative • Control – controls calls, authenticates calls, manages mobility, manages sessions, and is accommodated... the cellular network AMPS (Advanced Mobile Telephone System) that was developed by AT & T’s Bell Laboratories and operated between the 800 MHz and 900 MHz bands The development of GSM (Global System for Mobile Communications) began in 1982, and emerged globally in 1993 Early 1G networks offered small capacities, because they were not cellular, and an early internationally agreed standard analogue network . frequency band and was also used in South America, Far East, and in the Asia Pacific region including Australia and New Zealand. In the Asia Pacific country of Japan, NTT’s MCS system was the first.