Notiz: Henry Gantt (1861-1919)

Gehört zu: Consulting

Henry Gantt (1861-1919)

Henry Gantt developed the Gantt chart, which is used for scheduling multiple overlapping tasks over a time period. He focused on motivational schemes, emphasizing the greater effectiveness of rewards for good work (rather than penalties for poor work). He developed a pay incentive system with a guaranteed minimum wage and bonus systems for people on fixed wages. Also, Gantt focused on the importance of the qualities of leadership and management skills in building effective industrial organizations.

Notiz: Die C14-Methode

Die C14-Methode
C-14 wird in der Atmosphäre unter dem Einfluss von kosmischer Strahlung gebildet. Es verbindet sich mit Sauerstoff zu radioaktivem Kohlendioxid. Durch konstante Neubildung und laufenden Zerfall hat sich in der Luft ein Gleichgewicht gebildet. C-14 wird von den Pflanzen (Assimilation) bzw. durch alle von pflanzlicher Nahrung lebenden Organismen aufgenommen. In einem Baumast entsteht so eine ganz bestimmte Menge dieses Kohlenstoffes. Wird nun ein Ast von einem Baum abgebrochen, kann sich das C-14 Depot nicht mehr erneuern. Der C-14 Gehalt sinkt nach dem Zerfallsgesetz. Die vorhandene C-14-Menge kann analysiert werden und aufgrund der Halbwertszeiten wird auf die ursprüngliche Menge zurückgerechnet. Bis auf ein paar Jahre genau lässt sich so bestimmen, wann ein Baum abgestorben oder gefällt wurde.

Notiz: Background of the Fax Industry

Gehört zu: Telekommunikation

Background on the Fax Industry

The facsimile was invented in 1843 by Alexander Bain, earlier than the telephone invented by Bell in 1876. The facsimile came into practical use much more slowly than did the telephone. Using early achievements in electronic engineering such as the vacuum tube and photo cell, practical models were developed in the 1920’s in the United States, Germany, France, and Japan. After their introductions, facsimile apparatuses were used in specialized areas, such as for transmission of news pictures and weather maps, and pickup and delivery of telegrams.
Facsimiles are classified into either photographic facsimile, in which the original copy is reproduced faithfully with graded tonal densities, or document facsimile, in which the original copy is reproduced primarily with black and white.For many years before the growth of the fax machines, Alexander Bain modified a system of synchronized electric clocks to make the first fax machine. He devised a way of skimming raised metallic letters with a stylus attached to a pendulum. With this method, a stream of electric pulses were sent by a wire to the receiving device where a second synchronized pendulum swept across chemically-treated paper, leaving a dark mark wherever a pulse occurred. The rate at which the apparatus was capable of working was discovered accidentally by a broken spring. The fax principle was established and Bain received 7,000 for his telegraphic patent. The money he received was wasted in litigation and he died a poor man.

After the death of Bain, a handful of European inventors began to build upon his non-success and refine the fax principle. Giovanni Caselli, Frederick Bakewell, Ludovic d’Arlincourt and Edouard Belin each contributed innovations, but it was not until 1902 that Arthur Korn, a German, demonstrated the first photo-electric scanning fax system. The previous methods had depended upon Bain’s contact-scanning technique. In 1902, Dr. Arthur Korn developed a photoelectric scanning system for the transmission and reproduction of photography, and in 1907, he established a commercial picture transmission system. This system eventually linked Berlin, London and Paris and became the world’s first facsimile network. Facsimile then made slow but steady progress through the ‘20s and ‘30s, and in 1934 the Associated Press introduced a wire photo service. Korn’s breakthrough of giving the fax machine “sight” prompted serious commercial experimentation by three American telecommunications giants: AT&T, RCA and Western Union. Korn’s success and achievement in using the fax brought new development and direction for broadcast publishing to the United States.

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