The copies must then be physically distributed. The master should be returned to “the vault,” a physically secure facility (not in the classified data sense, unless this is also a valid concern) where all the engineering masters are retained. But, even if this is the current case, you should be making plans to move to an online specification library for cost, efficiency, and document configuration control purposes.Īfter a specification is formally released, the master must go to reproduction where sufficient copies are made to cover the needs for distribution and the library. If most of your specifications are in paper media, you may have no near-term option but to place them in a paper document library from which program personnel may check them out physically. These were published in paper form and distributed using shoe leather and mail systems. Years ago, specifications were crafted with typewriters and typesetting. Grady, in System Requirements Analysis (Second Edition), 2014 8.7.4.1 Paper Methods These printers operate at about 10 to 50 cps and are widely used in word-processing systems.
They are also called formed character printers because each print finger contains a fully formed character rather than a pattern of dots ( Figures 5-17 and 5-18). They are often called letter-quality printers because their print quality is as good as that of an office typewriter. These printers are ordinarily slower than dot-matrix printers, but their output is of better quality. The finger is then struck by a hammer that drives it against a ribbon that in turn strikes the paper. Both printers spin the print element at high speed until the finger with the appropriate symbol is located above the print position on the paper.
The thimble printer element has projections, called fingers, connected to a circular carrier and looks like a thimble used in sewing ( Figure 5-16). A daisy-wheel printer has characters on long fingers connected to a central pin, giving the appearance of a daisy ( Figure 5-15). Daisy-wheel and thimble printers are character printers that get their names from the shapes of their printing elements.
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