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21 systems design
Gen Mgtthe creation of a computer program to meet predetermined functional, operational, and personnel specifications. The systems design process involves the use of systems analysis and flowcharting of organizational functions and operations. It can be split into four stages: definition of the system’s goals; preparation of a conceptual model of how these goals will be achieved; development of a physical design; and preparation of a system specification. -
22 Keller, Friedrich Gottlieb
SUBJECT AREA: Paper and printing[br]b. 27 June 1818 Hainichen, Saxony, Germanyd. 8 September 1895 Krippen, Bad Schandau, Germany[br]German inventor of wood-pulp paper.[br]The son of a master weaver, he originally wished to become an engineer, but while remaining in the parental home he had to follow his father's trade in the textile industry, becoming a master weaver himself in 1839 at Hainichen. He was a good observer and a keen model maker. It was at this stage, in the early 1840s, that he began experimenting with a new material for papermaking. Until then the raw material had been waste rag from the textile industry, but the ever-increasing demands of the mechanical printing presses, especially those producing newspapers, were beginning to outstrip supply. Keller tried using pine wood ground with a wet grindstone. The mass of fibres that resulted was then heated with water to form a thick brew which he then strained through a cloth. By this means Keller obtained a pulp that could be used for papermaking. He constructed a simple grinding machine that could disintegrate the wood without splinters; this was used to make paper in the Altchemnitzer paper mill, and the newspaper Frankenberger Intelligenz-und Wochenblatt was the first to be printed on wood-pulp paper. Keller could not secure state funds to promote his invention, so he approached an expert in papermaking, Heinrich Voelter, Technical Director of the Vereinigten Bautzener Papierfabrik. Voelter put up 700 thaler, and in August 1845 the state of Saxony granted a patent in both their names. In 1848 the first practical machine for grinding wood was produced, but four years later the patent expired. Unfortunately Keller could not afford the renewal fee, and it was Voelter who developed the process of wood-pulp papermaking under his own name, leaving Keller behind. Without this invention, the output of paper from the mills could not have kept pace with the demands of the printing industry, and the mass readership that these technological developments made possible could not have been served. It is no fault of Keller's that wood-pulp paper contains within itself the seeds of its own deterioration and ultimate destruction, presenting librarians of today with an intractable problem of preservation. Keller's part in this technical breakthrough is established in his "ideas" notebook covering the years 1841 and 1842, preserved in the museum at Hainichen.[br]Further ReadingNeue deutsche Biographie. VDI Zeitschrift, Vol. 39, p. 1,238."EineErfindungvon Weltruf", 1969, VDI Nachrichten. Vol. 29, p. 18.Clapperton, History ofPapermaking Through the Ages (provides details of the development of wood-pulp papermaking in its historical context).LRDBiographical history of technology > Keller, Friedrich Gottlieb
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