Tt

T is for Technology, Thought and Tautology

T = Technology, Research and Development, Applied and Advanced.

Time

tech·nol·o·gy

tech·nol·o·gy (tĕk-nŏlʹə-jē) noun
Abbr. technol.

1.     a. The application of science, especially to industrial or commercial objectives. b. The scientific method and material used to achieve a commercial or industrial objective.

2.     Anthropology. The body of knowledge available to a civilization that is of use in fashioning implements, practicing manual arts and skills, and extracting or collecting materials.

[Greek tekhnologia, systematic treatment of an art or craft : tekhnē, skill + -logia, -logy.]

COMPUTER SCIENCE & ELECTRONICS

Automation

Automation, system using machines to perform tasks formerly done by human beings, and to control operations without human intervention.

Elements of Automation
The division of labor, reducing any process into its smallest steps, developed in the later 18th century. The division of labor increases production and reduces the skills required of workers. The simplification of work by the division of labor also made it possible for machines to duplicate the motions of the worker. As power technology evolved, these specialized machines were motorized. Power technology also gave rise to the factory system, because all workers and machines had to be near the power source.

In the 1920s the automobile industry adopted the assembly-line system of production. Industrial robots, originally designed to perform simple tasks in environments dangerous to human workers, now transfer, manipulate, and position workpieces. A number of separate machines are combined into what may be thought of as one large machine.

Feedback
All automatic-control mechanisms depend on the feedback principle. A feedback loop is a device that measures a physical quantity, compares it with a standard, and takes whatever preprogrammed action will keep the quantity within acceptable limits. With feedback devices, machines can start, stop, speed up, slow down, count, inspect, test, compare, and measure (see Cybernetics).

Computer Use
Computers and feedback loops can be used with machines governed by punched paper or magnetic tapes and with machining centers that can perform several different machining operations. In computer-aided design and computer-aided manufacture (CAD and CAM), a designer draws a part with a light pen on a cathode-ray tube screen. The computer directs a machining center that makes the part.

Automation in Industry
In the telephone industry, dialing, transmission, and billing are all done automatically. Railroads are controlled by automatic signaling devices. Word processors are used in many offices.

Use of automation varies with production systems. In the steel, beverage, and canned food industries, products may be produced in batches. For example, a steel furnace is loaded, brought up to heat, and emptied of steel without much automation. The steel ingots may be shaped automatically, however.

The oil and chemical industries use continuous-flow production. In a refinery, crude oil flows continuously through pipes in cracking, distillation, and reaction devices as it is being processed into gasoline and fuel oil. Automatic-control devices governed by microprocessors and coordinated by a central computer regulate both the flow and reaction rates.

The automobile and other consumer product industries use mass production techniques of step-by-step manufacture and assembly. This system resembles continuous flow but involves transfer machines. A transfer machine moves the piece being worked on from one machine tool to another and positions the workpiece for the next machine operation.

Automation and Society
Automation has increased free time and real wages for workers in industrialized nations. It has greatly increased production and lowered costs, making goods more available. Although the effects of automation on employment levels are debatable, it seems clear that the number of workers in more automated industries tends to be small, and that automation tends most easily to reduce the number of semiskilled workers.

MACHINES & TOOLS

Technology

Technology, general term for the processes by which human beings create tools and machines to increase their control and understanding of the material environment.

Ancient and Medieval Technology
Technology is perhaps best understood in a historical context that traces the evolution of early humans from a period of very simple tools to the complex, large-scale networks that influence most of contemporary human life. The graves of ancestors of modern human beings (see Human Evolution) contained pear-shaped axes, scrapers, knives, and other stone instruments indicating that the original hand ax had become a tool for making tools. This capacity for creating tools to make other tools distinguishes human beings from other animals.

The next major step in the history of technology was the control of fire. Besides the benefits of light and heat, fire was also used to bake clay pots that were used for cooking grains, brewing, and fermenting. Colorful minerals were pulverized to make pigments that were applied to the human body, clay utensils, baskets, clothing, and other objects. Early peoples also learned to create objects out of copper and bronze.

Eventually human societies shifted from nomadic hunting and herding to the practice of agriculture. These agricultural societies constructed stone buildings, used sickles to harvest grain, developed a primitive plowstick, and advanced their skills in metalworking. Two-wheeled carts were constructed for transportation, and the yoke, which was used with the plow, was adapted to these first land vehicles.

Urbanization
After about 4000 BC, one of the most complex creations of humankind appeared: the city. The accumulation of precious metals, the acquisition of the power to build defensive walls, and the control of armies and priests eventually resulted in the development of the kingship. The city also brought about a new division of labor: the caste system.

The first cities were built within walls for defense and organized for battle and conquest. Military technology developed in three stages. In the first stage the infantry developed with its leather or copper helmets, bows, spears, shields, and swords. This stage was followed by the development of chariots, which eventually became a light war machine that could outflank enemy infantry. The third stage of ancient military technology centered on increasing the mobility and speed of the cavalry.

Greek and Roman Technologies
Greece came to power through its skill in shipbuilding and trading and by its colonization along the Mediterranean Sea. The Romans were great technologists in the sense of organizing and building. A great change in engineering occurred as Roman construction shifted from building tombs, temples, and fortifications to erecting enormous systems of public works. Using water-resistant cement and the principle of the arch, Roman engineers built 70,800 km (44,000 mi) of roads across their vast empire. They also built numerous sports arenas and hundreds of aqueducts, sewers, and bridges.

Middle Ages
Great technological advancements occurred during the Middle Ages. In warfare, the crossbow was developed and gunpowder technologies resulted in the manufacture of guns, cannons, and mortars. Agriculture became more productive with the introduction of a heavier plow that had wheels, a horizontal plowshare, and a moldboard. One of the most important machines of medieval times was the windmill, which increased grain and timber production and produced millwrights experienced with the compound crank, cams, and other technologies for machines with gears. The spinning wheel improved the production of yarn and thread for cloth.

Innovations in transportation revolutionized the spread of technology and ideas across wide areas. Such devices as the horseshoe, the whiffletree (for harnessing animals to wagons), and the spring carriage facilitated transportation. In marine technology, the development of the deep keel, the triangular lateen sail, and the magnetic compass made sailing ships the most complex machines of the age.

Two other medieval inventions, the clock and the printing press, influenced all aspects of human life. The printing press set off a social revolution as literature became available to a wider audience. Intellectual life was no longer the exclusive domain of church and court, and literacy became a necessity of urban existence.

Modern Technology
By the end of the Middle Ages cities had become a central feature of Western life. The Industrial Revolution started in England, because that nation had the technological means, government encouragement, and a large and varied trade network. The first factories appeared in 1740, concentrating on textile production. As modern factories developed, the Industrial Revolution brought a new pattern to the division of labor. Factory workers were not required to be artisans and did not necessarily possess craft skills. Thus the work of men, women, and children became just another commodity in the production process.

As agricultural productivity increased and medical science developed, Western society pursued the advantages of technology despite its less pleasant aspects. Engineering achievements included the laying of the first Atlantic telegraph cable, the building of the Suez Canal and Panama Canal, and the construction of the Eiffel Tower, the Brooklyn Bridge, and the enormous iron passenger ship, the Great Eastern. Telegraph lines and railroads connected cities with one another. In the late 19th century the light bulb, created by American inventor Thomas Edison, began to replace candles and lamps, and within 30 years every industrial nation was generating electric power for lighting and other systems. The telephone, the phonograph, the wireless radio, the motion picture, the automobile, and the airplane transformed society by providing mobility, rapid communication, and a deluge of available information from mass media.

Reassessments of Technology
World War I (1914-1918) and the Great Depression forced a sobering reassessment of technology. The development of submarines, machine guns, battleships, and chemical warfare revealed the destructive side of technological change. Worldwide unemployment and the collapse of capitalistic institutions in the 1930s initiated a strong critique of the benefits that result from technological progress. The use of atomic weapons in World War II (1939-1945) showed how technology could threaten life on earth. The development of computers and transistors and the accompanying trend toward miniaturization continues to have a profound effect on society. The opportunities it offers are enormous, but so are the possibilities for invasion of privacy and for unemployment caused by automated systems. Beginning in the 1950s some observers started to warn that products of technology also had harmful or destructive aspects. Automobile exhausts polluted the atmosphere, pesticides threatened the food chain, and industrial wastes polluted groundwater.

T-Subjects:

Abstractions=Technology=the “artificial” inventions/creations

Tautology

http://en.wikipedia.org/wiki/Tautology_(logic)

In logic, a tautology (from the Greek word ταυτολογία) is a formula which is true in every possible interpretation. Philosopher Ludwig Wittgenstein first applied the term to redundancies of propositional logic in 1921; it had been used earlier to refer to rhetorical tautologies, and continues to be used in that alternate sense today.

A formula is satisfiable if it is true under at least one interpretation, and thus a tautology is a formula whose negation is unsatisfiable. Unsatisfiable statements, both through negation and affirmation, are known formally as contradictions. A formula that is neither a tautology nor a contradiction is said to be logically contingent. Such a formula can be made either true or false based on the values assigned to its propositional variables. The double turnstile notation \vDash S is used to indicate that S is a tautology. Tautology is sometimes symbolized by “Vpq“, and contradiction by “Opq“. The tee symbol \top is sometimes used to denote an arbitrary tautology, with the dual symbol \bot (falsum) representing an arbitrary contradiction.

Tautologies are a key concept in propositional logic, where a tautology is defined as a propositional formula that is true under any possible Boolean valuation of its propositional variables. A key property of tautologies in propositional logic is that an effective method exists for testing whether a given formula is always satisfied (or, equivalently, whether its negation is unsatisfiable).

The definition of tautology can be extended to sentences in predicate logic, which may contain quantifiers, unlike sentences of propositional logic. In propositional logic, there is no distinction between a tautology and a logically valid formula. In the context of predicate logic, many authors define a tautology to be a sentence that can be obtained by taking a tautology of propositional logic and uniformly replacing each propositional variable by a first-order formula (one formula per propositional variable). The set of such formulas is a proper subset of the set of logically valid sentences of predicate logic (which are the sentences that are true in every model).


Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s