Invention of Press and Advertisement Technology Essay

Invention of Press and Advertisement Technology - Essay Example The parts of the Columbian printing press included the American eagle perching rebelliously with not only outstretched wings but also open beak on the focal counterbalance lever. The eagle acted as a counterbalance weight that was adjusted by sliding it along the focal counterbalance lever (Mullins 17). The clutching of a flight of Jove’s thunderbolts by the eagle’s talons represents war while on the contrary the olive branch of peace, as well as Horn of Plenty, signifies prosperity. The main counterbalance is tipped in one of its ends to form an arrow that rests in the horn-like opening of the crescent moon. The other end of the counterbalance is coiled to form something like a dolphin; its open jaws suitably hold the hook that connects it with the top end of the great lever (Mullins 17). A similar creature (dolphin) also extends along the top front of the great lever. The Columbian has two pillars that are decorated with the caduceus. The right-hand pillar also has a conventional ear of wheat near its top. The type table of the Columbian was also made out of iron, and it was wound below the printing platen (Mullins 17). Printing of the materials was enhanced by exerting force through a wood on the printing table. The Columbian printing press stands on four legs made of iron. The ends of the legs are molded to form something like the paws of a lion. Despite proving to be a bit faster than the past printers, advancement in technology led to other inventions that led to the abandonment of the use of weights and levers. For instance, mechanization of printing was started in 1824. As a result of this, gears and power were added to the wooden-framed platen press. This type of press led to the production of high-quality prints in the nineteenth century. The new media today incorporates computers into the printing process. The balancing of the elements for quality production of prints is not done physically by balancing weights. The development of electronic devices in addition to other technological devices has led to the evolution of printing.

Epidemiology Essay Example | Topics and Well Written Essays - 2250 words

Epidemiology - Essay Example In contrast, absolute measures, computed as a difference rather than a ratio, produce estimates with quite different interpretations. a) The type of misclassification portrayed in this case study is non- differential and random. The same misclassification occurs in the same proportion in each group. The percentage unto which the cases were underestimated is the same percentage, which the controls were over estimated. These leads to an underestimation of the true association hence the true association cannot be established. A relative risk ratio of more than one indicates that the occurrence of the event at hand is more likely to the experimental group than the control group. This misclassification reduced the relative risk ratio hence reducing the likelihood of the event occurring to the experimental group. This means underestimating the true association. b. Outcome variables of a study are measurements of population’s current status which might include mean, mode and median of continuous counts of measurements for example radio frequency exposure in megahertz, age, duration of exposure of radiation in hours and type of phone used. c. Study factors (exposures): cellular phone calls radio frequency measure by the kind of phone used, the duration of use and the ear use to receive the call. The second factor is brain tumor measured by anatomical area of the tumor. 2. a. The participation rate in this study is the percentage of the total number targeted that participated in the study =2899/3234*100=89.64%. The high participation rate is one of the characteristic of a good epidemiologic study. This implies that the results of the study are highly representative of the actual population. b. Response rate in survey research refers to the ratio of number of people who answered the survey divided by the number of people in the sample. It is usually expressed in the form of a