Introduction: The Substitution of Human Faculties with Technology: Powered Machines The development of the steam engine in 1776 represented a major advance in the construction of powered machines and marked the beginning of the Industrial Revolution. Powered engines and machines soon became common and led to the first extensive mechanization of manufacturing processes. The development of |
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In Search of Reliable Internet Measurement Data Newspapers and magazines frequently report growth rates of Internet usage, number of users, hosts, and domains that seem to be beyond all expectations. Growth rates are expected to accelerate exponentially. However, Internet measurement data are anything thant reliable and often quite fantastic constructs, that are nevertheless jumped upon by many media and decision makers because the technical difficulties in measuring Internet growth or usage are make reliable measurement techniques impossible. Equally, predictions that the Internet is about to collapse lack any foundation whatsoever. The researchers at the Size and Growth In fact, "today's Internet industry lacks any ability to evaluate trends, identity performance problems beyond the boundary of a single ISP (Internet service provider, M. S.), or prepare systematically for the growing expectations of its users. Historic or current data about traffic on the Internet infrastructure, maps depicting ... there is plenty of measurement occurring, albeit of questionable quality", says K. C. Claffy in his paper Internet measurement and data analysis: topology, workload, performance and routing statistics (http://www.caida.org/Papers/Nae/, Dec 6, 1999). Claffy is not an average researcher; he founded the well-known So his statement is a slap in the face of all market researchers stating otherwise. In a certain sense this is ridiculous, because since the inception of the So what are the reasons for this inability to evaluate trends, identity performance problems beyond the boundary of a single ISP? First, in early 1995, almost simultaneously with the worldwide introduction of the "There are many estimates of the size and growth rate of the Internet that are either implausible, or inconsistent, or even clearly wrong", K. G. Coffman and Andrew, both members of different departments of What is measured and what methods are used? Many studies are devoted to the number of users; others look at the number of computers connected to the Internet or count You get the clue of their focus when you bear in mind that the Internet is just one of many networks of networks; it is only a part of the universe of computer networks. Additionally, the Internet has public (unrestricted) and private (restricted) areas. Most studies consider only the public Internet, Coffman and Odlyzko consider the long-distance private line networks too: the corporate networks, the Hosts The Despite the small sample, this method has at least one flaw: Internet Weather Like daily weather, traffic on the Internet, the conditions for data flows, are monitored too, hence called Internet weather. One of the most famous Internet Hits, Page Views, Visits, and Users Let us take a look at how these hot lists of most visited Web sites may be compiled. I say, may be, because the methods used for data retrieval are mostly not fully disclosed. For some years it was seemingly common sense to report requested files from a Web site, so called "hits". A method not very useful, because a document can consist of several files: graphics, text, etc. Just compile a document from some text and some twenty flashy graphical files, put it on the Web and you get twenty-one hits per visit; the more graphics you add, the more hits and traffic (not automatically to your Web site) you generate. In the meantime page views, also called page impressions are preferred, which are said to avoid these flaws. But even page views are not reliable. Users might share computers and corresponding Especially the editors of some electronic journals (e-journals) rely on page views as a kind of ratings or circulation measure, Rick Marin reports in the More advanced, but just slightly better at best, is counting visits, the access of several pages of a Web site during one session. The problems already mentioned apply here too. To avoid them, newspapers, e.g., establish registration services, which require password authentication and therefore prove to be a kind of access obstacle. But there is a different reason for these services. For content providers users are virtual users, not unique persons, because, as already mentioned, computers and For If you like to play around with Internet statistics instead, you can use Robert Orenstein's Measuring the Density of Measuring the Density of Dodge and Shiode used data on the ownership of IP addresses from |
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The 19th Century: First Programmable Computing Devices Until the 19th century "early computers", probably better described as calculating machines, were basically mechanical devices and operated by hand. Early Therefore After working on the Difference Engine for ten years Babbage was inspired to build another machine, which he called Analytical Engine. Its invention was a major step towards the design of modern computers, as it was conceived the first general-purpose computer. Instrumental to the machine's design was his assistant, Augusta Ada King, Countess of Lovelace, the first female computer programmer. The second major breakthrough in the design of computing machines in the 19th century may be attributed to the American inventor Herman Hollerith. He was concerned with finding a faster way to compute the U.S. census, which in 1880 had taken nearly seven years. Therefore Hollerith invented a method, which used cards to store data information which he fed into a machine that compiled the results automatically. The punch cards not only served as a storage method and helped reduce computational errors, but furthermore significantly increased speed. Of extraordinary importance for the evolution of digital computers and |
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James Watt b. January 19, 1736, Greenock, Renfrewshire, Scotland d. August 25, 1819, Heathfield Hall, Warwick, England Scottish instrument maker and inventor whose steam engine contributed substantially to the Industrial Revolution. He was elected fellow of the Royal Society of London in 1785. |
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Assembly line An assembly line is an industrial arrangement of machines, equipment, and workers for continuous flow of workpieces in |
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Telephone The telephone was not invented by Alexander Graham Bell, as is widely held to be true, but by Philipp Reiss, a German teacher. When he demonstrated his invention to important German professors in 1861, it was not enthusiastically greeted. Because of this dismissal, no financial support for further development was provided to him. And here Bell comes in: In 1876 he successfully filed a patent for the telephone. Soon afterwards he established the first telephone company. |
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AT&T Labs-Research The research and development division of http://www.research.att.com/ |
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Intranet As a |
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Computer programming language A computer programming language is any of various languages for expressing a set of detailed instructions for a digital computer. Such a language consists of characters and rules for combining them into symbols and words. |
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Electronic Data Interchange (EDI) EDI is an international standard relating to the exchange of trade goods and services. It enables trading partners to conduct routine business transactions, such as purchase orders, invoices and shipping notices independent of the computer platform used by the trading partners. Standardization by EDI translation software assures the correct interpretation of data. EDI might become increasingly important to electronic commerce. |
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Proxy Servers A proxy server is a server that acts as an intermediary between a workstation user and the Internet so that security, administrative control, and caching service can be ensured. A proxy server receives a request for an Internet service (such as a Web page request) from a user. If it passes filtering requirements, the proxy server, assuming it is also a cache server, looks in its local cache of previously downloaded Web pages. If it finds the page, it returns it to the user without needing to forward the request to the Internet. If the page is not in the cache, the proxy server, acting as a client on behalf of the user, uses one of its own Source: Whatis.com |
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