History Of Communications

1. History Of Communications By: Taylor Driscoll

2. Ancient, Classical And Dark Ages(500,000 B.C.- 900A.D.) The First Calendar 4241B.C. Egyptian • The ancient civil egyptian calendar had a year that was 365 days long and was divided into 12 months of 30 days each, plus five extra days (epagomenae, from Greek ἐπαγόμεναι) at the end of the year. The months were divided into three weeks of ten days each. Because the ancient Egyptian year was almost a quarter of a day shorter than the solar year and stellar events therefore "wandered" through the calendar, it has been referred to as the annusvagus, or "wandering year".

3. The people that were involed? • A tablet from the reign of King Djer (c. 3000 BC) was conjectured by early Egyptologists to indicate that the Egyptians had already established a link between the heliacal rising of Sirius (EgyptianSopdet, GreekΣείριοςSeirios) and the beginning of the year. However, more recent analysis of the pictorial scene on this tablet has questioned whether it actually refers to Sothis at all.[2] Current knowledge of this period remains a matter more of speculation than of established fact.

4. Types of technology that had to be invented? • The Egyptians may have used a luni-solar calendar at an earlier date, with the intercalation of an extra month regulated either by the heliacal rising of Sothis or by the inundation of the fields by the Nile.[3] The first inundation according to the calendar was observed in Egypt's first capital, Memphis, at the same time as the heliacal rising of Sirius. The Egyptian year was divided into the three seasons of akhet (Inundation), peret (Growth - Winter) and shemu (Harvest - Summer).

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6. The Invention of the printing press(1450, Johannes Gutenburg) • A printing press is a device for evenly printing ink onto a print medium substrate such as paper or cloth. The device applies pressure to a print medium that rests on an inked surface made of movable type, thereby transferring the ink. Typically used for texts, the invention and spread of the printing press are widely regarded as among the most influential events in the second millennium[1] revolutionizing the way people conceive and describe the world they live in, and ushering in the period of modernity.

7. The People involved? • The world's first movable type printing technology was invented and developed in China by the Han Chinese printer Bi Sheng between the years 1041 and 1048. In Korea, the movable metal type printing technique was invented in the early thirteenth century during the Goryeo Dynasty. In the West, the invention of an improved movable type mechanical printing technology in Europe is credited to the German printer Johannes Gutenberg in 1450. The exact date of Gutenberg's press is debated based on existing screw presses. Gutenberg, a goldsmith by profession, developed a printing system by both adapting existing technologies and making inventions of his own. His newly devised hand mould made possible the rapid creation of metal movable type in large quantities. The printing press displaced earlier methods of printing and led to the first assembly line-style mass production of books. A single Renaissance printing press could produce 3,600 pages per workday, compared to about 2,000 by typographic block-printing and a few by hand-copying . Books of bestselling authors such as Luther and Erasmus were sold by the hundreds of thousands in their lifetime.

8. Types of technology that had to be invented? At the same time, a number of medieval products and technological processes had reached a level of maturity which allowed their potential use for printing purposes. Gutenberg took up these far-flung strands, combined them into one complete and functioning system, and perfected the printing process through all its stages by adding a number of inventions and innovations of his own : have also been inspired by the paper presses which had spread through the German lands since the late 14th century and which worked on the same mechanical principles. Gutenberg adopted the basic design, thereby mechanizing the printing process. Printing, however, put a demand on the machine quite different from pressing. Gutenberg adapted the construction so that the pressing power exerted by the platen on the paper was now applied both evenly and with the required sudden elasticity. To speed up the printing process, he introduced a movable undertable with a plane surface on which the sheets could be swiftly changed. Movable type sorted in a letter case and loaded in a composing stick on top

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10. The Development Electrical generator(1831, Michael Faraday) • before the connection between magnetism and electricity was discovered, electrostatic generators were used. They operated on electrostatic principles. Such generators generated very high voltage and low current. They operated by using moving electrically charged belts, plates, and disks that carried charge to a high potential electrode. The charge was generated using either of two mechanisms:Because of their inefficiency and the difficulty of insulating machines that produced very high voltages, electrostatic generators had low power ratings, and were never used for generation of commercially significant quantities of electric power. The Wimshurst machine and Van de Graaff generator are examples of these machines that have survived.

11. The people involed? • A Van de Graaff generator is an electrostatic generator which uses a moving belt to accumulate very high voltages on a hollow metal globe on the top of the stand. It was invented by American physicist Robert J. Van de Graaff in 1929. The potential difference achieved in modern Van de Graaff generators can reach 5 megavolts. The Van de Graaff generator can be thought of as a constant-current source connected in parallel with a capacitor and a very large electrical resistance, so it can produce a visible electrical discharge to a nearby grounding surface which can potentially cause a "spark" depending on the voltage.

12. Types of technology that had to be invented? • ectricity generation is the process of generating electric power from other sources of primary energy. The fundamental principles of electricity generation were discovered during the 1820s and early 1830s by the British scientist Michael Faraday. His basic method is still used today: electricity is generated by the movement of a loop of wire, or disc of copper between the poles of a magnet. For electric utilities, it is the first process in the delivery of electricity to consumers. The other processes, electricity transmission, distribution, and electrical power storage and recovery using pumped-storage methods are normally carried out by the electric power industry. Electricity is most often generated at a power station by electromechanical generators, primarily driven by heat engines fueled by chemical combustion or nuclear fission but also by other means such as the kinetic energy of flowing water and wind. Other energy sources include solar photovoltaics and.

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14. The invention of the television(1926, john logiebaird) • the development of television was the result of work by many inventors. Among them, Baird was a prominent pioneer and made major advances in the field. Many historians credit Baird with being the first to produce a live, moving, greyscale television image from reflected light. Baird achieved this, where other inventors had failed, by obtaining a better photoelectric cell and improving the signal conditioning from the photocell and the video amplifier. • Between 1902 and 1907, Arthur Korn invented and built the first successful signal-conditioning circuits for image transmission. The circuits overcame the image-destroying lag effect that is part of selenium photocells. Korn's compensation circuit allowed him to send still pictures by telephone or wireless between countries and even over oceans, while his circuit operated without benefit of electronic amplification.[8]Korn's success at transmitting halftone still images suggested that such compensation circuits might work in television. Baird was the direct beneficiary of Korn's research and success.[9][10]

15. The people involved? • The beginnings of mechanical television can be traced back to the discovery of the photoconductivity of the element selenium by Willoughby Smith in 1873, the invention of a scanning disk by Paul Gottlieb Nipkow in 1884 and John Logie Baird's demonstration of televised moving images in 1926. • As a 23-year-old German university student, Nipkow proposed and patented the first electromechanical television system in 1884.[1] Although he never built a working model of the system, variations of Nipkow's spinning-disk "image rasterizer" for television became exceedingly common, and remained in use until 1939.[2]ConstantinPerskyi had coined the word television in a paper read to the International Electricity Congress at the International World Fair in Paris on August 25, 1900. Perskyi's paper reviewed the existing electromechanical technologies, mentioning the work of Nipkow and others. However, it was not until 1907 that developments in amplification tube technology, by Lee de Forest and Arthur Korn among others, made the design practical. • The first demonstration of the instantaneous transmission of images was by Georges Rignoux and A. Fournier in Paris in 1909. A matrix of 64 selenium cells, individually wired to a mechanical commutator, served as an electronic retina. In the receiver, a type of Kerr cell modulated the light and a series of variously angled mirrors attached to the edge of a rotating disc scanned the modulated beam onto the display screen. A separate circuit regulated synchronization. The 8x8 pixel resolution in this proof-of-concept demonstration was just sufficient to clearly transmit individual letters of the alphabet. An updated image was transmitted "several times" each second.[5]

16. Type of technology that needed to be invented? • the cathode ray tube (CRT) is a vacuum tube containing one or more electron guns (a source of electrons or electron emitter) and a fluorescent screen used to view images.[1] It has a means to accelerate and deflect the electron beam(s) onto the screen to create the images. The images may represent electrical waveforms (oscilloscope), pictures (television, computer monitor), radar targets or others. CRTs have also been used as memory devices, in which case the visible light emitted from the fluorescent material (if any) is not intended to have significant meaning to a visual observer (though the visible pattern on the tube face may cryptically represent the stored data). • The CRT uses an evacuated glass envelope which is large, deep (i.e. long from front screen face to rear end), fairly heavy, and relatively fragile. As a matter of safety, the face is typically made of thick lead glass so as to be highly shatter-resistant and to block most X-ray emissions, particularly if the CRT is used in a consumer product. • CRTs have largely been superseded by newer display technologies such as LCD, plasma display, and OLED, which have lower manufacturing costs, power consumption, weight and bulk. • The vacuum level inside the tube is high vacuum on the order of 0.01 Pato133 nPa.[3] • In television sets and computer monitors, the entire front area of the tube is scanned repetitively and systematically in a fixed pattern called a raster. An image is produced by controlling the intensity of each of the three electron beams, one for each additive primary color (red, green, and blue) with a video signal as a reference.[4] In all modern CRT monitors and televisions, the beams are bent by magnetic deflection, a varying magnetic field generated by coils and driven by electronic circuits around the neck of the tube, although electrostatic deflection is commonly used in oscilloscopes, a type of diagnostic instrument.

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18. The development of the internet(1968 U.S Army ) • The Internet was the result of some visionary thinking by people in the early 1960s who saw great potential value in allowing computers to share information on research and development in scientific and military fields. J.C.R. Licklider of MIT first proposed a global network of computers in 1962, and moved over to the Defense Advanced Research Projects Agency (DARPA) in late 1962 to head the work to develop it. Leonard Kleinrock of MIT and later UCLA developed the theory of packet switching, which was to form the basis of Internet connections. Lawrence Roberts of MIT connected a Massachusetts computer with a California computer in 1965 over dial-up telephone lines. It showed the feasibility of wide area networking, but also showed that the telephone line's circuit switching was inadequate. Kleinrock's packet switching theory was confirmed. Roberts moved over to DARPA in 1966 and developed his plan for ARPANET. These visionaries and many more left unnamed here are the real founders of the Internet.

19. The People involved? • The main people involved in the development of the internet include Arthur Clark and Tim Berners-lee. They both designed the hyper text project architecture which is the world wide web.

20. Types of technology that had to be invented ? • he communications infrastructure of the Internet consists of its hardware components and a system of software layers that control various aspects of the architecture. While the hardware can often be used to support other software systems, it is the design and the rigorous standardization process of the software architecture that characterizes the Internet and provides the foundation for its scalability and success. The responsibility for the architectural design of the Internet software systems has been delegated to the Internet Engineering Task Force (IETF).[32] The IETF conducts standard-setting work groups, open to any individual, about the various aspects of Internet architecture. Resulting discussions and final standards are published in a series of publications, each called a Request for Comments (RFC), freely available on the IETF web site. • The principal methods of networking that enable the Internet are contained in specially designated RFCs that constitute the Internet Standards. Other less rigorous documents are simply informative, experimental, or historical, or document the best current practices (BCP) when implementing Internet technologies.

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