Information and Papers
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Wikipedia-Article "Information"
Information is a word which has many different meanings in everyday usage and in specialized contexts, but as a rule, the concept is closely related to others such as data, instruction, knowledge, meaning, communication, representation, and mental stimulus.
Information is a message, something to be communicated from the sender to the receiver. If information is viewed merely as a message, it does not have to be accurate. It may be a truth or a lie, or just a sound of a kiss. Strangely it may even be a disruptive noise used to inhibit the flow of communication and create misunderstanding. This model assumes a sender and a receiver, and does not attach any significance to the idea that information is something that can be extracted from an environment, e.g., through observation or measurement. Information in this sense is simply any message the sender chooses to create.
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Measuring information
The view of information as a message came into prominence with the publication in 1948 of an influential paper by Claude Shannon, "A Mathematical Theory of Communication." This paper provides the foundations of information theory and endows the word information not only with a technical meaning but also a measure. If the sending device is equally likely to send any one of a set of N messages, then the preferred measure of "the information produced when one message is chosen from the set" is the base two logarithm of N (This measure is called self-information). In this paper, Shannon continues:
- The choice of a logarithmic base corresponds to the choice of a unit for measuring information. If the base 2 is used the resulting units may be called binary digits, or more briefly bits, a word suggested by J. W. Tukey. A device with two stable positions, such as a relay or a flip-flop circuit, can store one bit of information. N such devices can store N bits ... [The Bell System Technical Journal, Vol. 27, p. 379, (July 1948).]
A complementary way of measuring information is provided by Algorithmic information theory. In brief, this measures the information content of a list of symbols based on how predictable they are, or more specifically how easy it is to generate the list. The sequence below would have a very low algorithmic information measurement since it is a very predictable pattern, and as the pattern continues the measurement would not change. Shannon information would give the same information measurement for each symbol, since they are statistically random, and each new symbol would increase the measurement.
- 123456789101112131415161718192021
Also see: lexicographic information cost
Information as a pattern
Information is any represented pattern. This view assumes neither accuracy nor directly communicating parties, but instead assumes a separation between an object and its representation, as well as the involvement of someone capable of understanding this relationship. This view seems therefore to require a conscious mind. Consider the following example: economic statistics represent an economy, however inaccurately. What are commonly referred to as data in computing, statistics, and other fields, are forms of information in this sense. The electro-magnetic patterns in a computer network and connected devices are related to something other than the pattern itself, such as text to be displayed and keyboard input. Signals, signs, and symbols are also in this category. On the other hand, according to semiotics, data is symbols with certain syntax and information is data with a certain semantic. Painting and drawing contain information to the extent that they represent something such as an assortment of objects on a table, a profile, or a landscape. In other words, when a pattern of something is transposed to a pattern of something else, the latter is information. This type of information still assumes some involvement of conscious mind, of either the entity constructing the representation, or the entity interpreting it.
When one constructs a representation of an object, one can selectively extract from the object (sampling) or use a system of signs to replace (encoding), or both. The sampling and encoding result in representation. An example of the former is a "sample" of a product; an example of the latter is "verbal description" of a product. Both contain information of the product, however inaccurate. When one interprets representation, one can predict a broader pattern from a limited number of observations (inference) or understand the relation between patterns of two different things (decoding). One example of the former is to sip a soup to know if it is spoiled; an example of the latter is examining footprints to determine the animal and its condition. In both cases, information sources are not constructed or presented by some "sender" of information. To repeat, information in this sense does not assume direct communication, but it assumes involvement of some conscious mind.
Regardless, information is dependent upon, but usually unrelated to and separate from, the medium or media used to express it. In other words, the position of a theoretical series of bits, or even the output once interpreted by a computer or similar device, is unimportant, except when someone or something is present to interpret the information. Therefore, a quantity of information is totally distinct from its medium.
Information as sensory input
Often information is viewed as a type of input to an organism or designed device. Inputs are of two kinds. Some inputs are important to the function of the organism (for example, food) or device (energy) by themselves. In his book Sensory Ecology, Dusenbery called these causal inputs. Other inputs (information) are important only because they are associated with causal inputs and can be used to predict the occurrence of a causal input at a later time (and perhaps another place). Some information is important because of association with other information but eventually there must be a connection to a causal input. In practice, information is usually carried by weak stimuli that must be detected by specialized sensory systems and amplified by energy inputs before they can be functional to the organism or device. For example, light is often a causal input to plants but provides information to animals. The colored light reflected from a flower is too weak to do much photosynthetic work but the visual system of the bee detects it and the bee's nervous system uses the information to guide the bee to the flower, where the bee often finds nectar or pollen, which are causal inputs, serving a nutritional function.
Information is any type of sensory input. When an organism with a nervous system receives an input, it transforms the input into an electrical signal. This is regarded information by some. The idea of representation is still relevant, but in a slightly different manner. That is, while abstract painting does not represent anything concretely, when the viewer sees the painting, it is nevertheless transformed into electrical signals that create a representation of the painting. Defined this way, information does not have to be related to truth, communication, or representation of an object. Entertainment in general is not intended to be informative. Music, the performing arts, amusement parks, works of fiction and so on are thus forms of information in this sense, but they are not forms of information according to the previous definitions above. Consider another example: food supplies both nutrition and taste for those who eat it. If information is equated to sensory input, then nutrition is not information but taste is.
Information as an influence which leads to a transformation
Information is any type of pattern that influences the formation or transformation of other patterns. In this sense, there is no need for a conscious mind to perceive, much less appreciate, the pattern. Consider, for example, DNA. The sequence of nucleotides is a pattern that influences the formation and development of an organism without any need for a conscious mind. Systems theory at times seems to refer to information in this sense, assuming information does not necessarily involve any conscious mind, and patterns circulating (due to feedback) in the system can be called information. In other words, it can be said that information in this sense is something potentially perceived as representation, though not created or presented for that purpose.
When Marshall McLuhan speaks of media and their effects on human cultures, he refers to the structure of artifacts that in turn shape our behaviors and mindsets. Also, pheromones are often said to be "information" in this sense.
In 2003, J. D. Bekenstein claimed there is a growing trend in physics to define the physical world as being made of information itself (and thus information is defined in this way).
See the section below on information as a property in physics. (Also see Gregory Bateson.)
Information as a property in physics
Main article: Physical information
Information has a well defined meaning in physics. Examples of this include the phenomenon of quantum entanglement where particles can interact without reference to their separation or the speed of light. Information itself cannot travel faster than light even if the information is transmitted indirectly. This could lead to the fact that all attempts at physically observing a particle with an "entangled" relationship to another are slowed down, even though the particles are not connected in any other way other than by the information they carry.
Another link is demonstrated by the Maxwell's demon thought experiment. In this experiment, a direct relationship between information and another physical property, entropy, is demonstrated. A consequence is that it is impossible to destroy information without increasing the entropy of a system; in practical terms this often means generating heat. Thus, in the study of logic gates, the theoretical lower bound of thermal energy released by an AND gate is more than for the NOT gate (because information is destroyed in an AND gate and simply converted in an NOT gate). Physical information is of particular importance in the theory of quantum computers.
Etymology
According to the Oxford English Dictionary, the earliest historical meaning of the word information in English was the act of informing, or giving form or shape to the mind, as in education, instruction, or training. A quote from 1387: "Five books come down from heaven for information of mankind." It was also used for an item of training, e.g. a particular instruction. "Melibee had heard the great skills and reasons of Dame Prudence, and her wise informations and techniques." (1386)
The English word was apparently derived by adding the common "noun of action" ending "-ation" (descended through French from Latin "-tio") to the earlier verb to inform, in the sense of to give form to the mind, to discipline, instruct, teach: "Men so wise should go and inform their kings." (1330) Inform itself comes (via French) from the Latin verb informare, to give form to, to form an idea of. Furthermore, Latin itself already even contained the word informatio meaning concept or idea, but the extent to which this may have influenced the development of the word information in English is unclear.
As a final note, the ancient Greek word for form was eidos, and this word was famously used in a technical philosophical sense by Plato (and later Aristotle) to denote the ideal identity or essence of something (see The Forms).
References
- Bekenstein, Jacob D. (2003, August). Information in the holographic universe. Scientific American. Retrieved from http://www.referencenter.com
See also
- Algorithmic information theory
- Classified information
- Fisher information
- Freedom of information
- Information entropy
- Propaganda model
- Free Information Infrastructure
- Information theory
- Information overload
- Information processing
- Information processor
- Information mapping
- Information technology
- Library and Information Science
- Medium
- Observation
- Physical information
- Prediction
- Receiver operating characteristic
- Systems theory and cybernetics
- Satisficing
- The Information highway - A nickname of the Internet, dubbed the greatest source of information.
External links
Wikipedia-Article "Papers"
- For other uses, see Paper (disambiguation).
Paper is a thin, flat material produced by the compression of fibres. The fibres used are usually natural and based upon cellulose. The most common material is wood pulp from pulpwood (largely softwood) trees such as spruces, but other vegetable fibre materials including cotton, hemp, linen, and rice may be used. A stack of 500 sheets of paper is called a ream. Though generally considered a flexible material, the edges of paper sheets can act as very thin, fine-toothed saws, leading to paper cuts.
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Manufacturing
Whether done by hand or with a paper machine, the paper making process has three simple steps:
Preparation of the fibres
The material to be used for making paper is first converted into pulp, a concentrated mixture of fibres suspended in liquid. The source of fibre is often natural (softwood, hardwood, etc.) or recycled (old corrugated boxes, newsprint, mixed office waste, etc.).
When natural materials are used to make paper, it is essential to break down the lignin inside of the cell walls. This may be done mechanically or the lignin can be removed completely by a chemical process. These processes are not needed when breaking down recycled fibres.
Pulp that has been broken down mechanically is often known as "groundwood pulp". The mechanical process to break down the wood chips into fibers uses no chemicals. Since the lignin is retained in mechanical pulp, there is a relatively high yield (90-98%) However, since the lignin is retained in pulp, paper made from this grade will tend to yellow when exposed to air and light. Because of this, mechanical pulp is most often used for newspapers and other non-permanent goods.
Pulp that is broken down chemically is known as "chemical pulp" The main purpose of a chemical pulping process is to break down the chemical structure of lignin and render is soluable in a liquid (most often water) so it may be washed from the remaining fibers. Removing the lignin from the wood chips also serves to break apart the chips into fibers that compose the pulp.
Recycled fibres do not need to be pulped in the conventional sense. These fibres have already been treated once, so instead they need a more gentle process to break the fibers apart while preserving their integrity.
Once the fibres have been extracted, they may also be bleached, dyed, or have additional ingredients added to alter the appearance of the final product. The addition of Kaolin (or calcium carbonate) for example results in the glossy papers typically used for magazines.
Sheet formation
The pulp mixture is then further diluted with water resulting in a very thin slurry. This dilute slurry is drained through a fine-mesh moving screen to form a fibrous web. A watermark may be impressed into the paper at this stage of the process. This moving web is pressed and dried into a continuous sheet of paper.
In the case of the mould process, a quantity of the pulp is placed into a form, with a wire-mesh base (or other draining device), so that the fibers are left coated on the mesh and excess water can drain away. At this time, pressure may be applied to remove more water through a squeezing action. The paper may then be removed from the mould, wet or dry, and go on to further processing.
Most mass-produced paper is made using a continuous (Fourdrinier) process to form a reel or web. When dried, this continuous web may be cut into rectangular sheets by slitting the web vertically and then cutting it horizontally to the desired length. Standard sheet sizes are prescribed by governing bodies such as the International Organization for Standardization (ISO).
Drying
After the paper web is produced, the water must be removed from it in order to create a usable products. This is accomplished through pressing and drying. The methods of doing so vary between the different processes used to make paper, but the concepts remain the same.
Pressing the sheet removes the water by force. Once the water is forced from the sheet, there must be another absorbant material to absorb the water removed from the sheet. On a paper machine this is a felt (not to be confused with the traditional felt ) and when handmade, this is often a blotter sheet.
Drying involves using air and or heat to remove water from the paper sheet. In the earliest days of papermaking this was done by hanging the paper sheets like laundry. In more modern times, various forms of heated drying mechanisms are used. On the paper machine, the most common is a steam-heated can dryer. These dryer cans heat to temperatures above 200ºF and are used in long sequences of more than 40 cans. The heat produced by these can easily dry the paper to less than 6% moisture.
Applications
- To write or print on: the piece of paper becomes a document; this may be for keeping a record (or in the case of printing from a computer or copying from another paper: an additional record) and for communication; see also reading.
- To represent a value:
- For entertainment:
- For packaging:
- For cleaning (see also tissue, Kleenex):
- For construction
History
The word paper comes from ancient Egyptian writing material called papyrus, which was woven from papyrus plants. Papyrus was produced as early as 3000 BC in Egypt, and then in ancient Greece and Rome. Further north, parchment or vellum, made of processed sheepskin or calfskin, replaced papyrus which requires subtropical conditions for growth. In China, documents were ordinarily written on bamboo, making them very heavy and awkward to transport. Silk was sometimes used, but was usually too expensive to consider. Most of the above materials were rare and costly.
The Chinese court official Cai Lun described the modern method of papermaking in AD 105; he was the first person to describe the method of making paper from cotton rags. Other sources date back the invention of papermaking in China to 150 BC. It spread slowly outside of China; other East Asian cultures, even after seeing paper, could not figure out how to make it themselves. Instruction in the manufacturing process was required, and the Chinese were reluctant to share their secrets. The technology was firstly transferred to Korea in 600 and then imported to Japan by Korean Buddhist priest, Dam Jing, in 625, where fibres (called bast) from the mulberry tree were used. After commercial trades and the defeat of the Chinese in the Battle of Talas, the invention spread to the Middle East, where it was adopted by the Indians and subsequently by the Italians in about the 13th century. They used hemp and linen rags. The oldest known paper document in the West is the Missel of Silos from the 11th century.
Some historians speculate that paper was the key element in global cultural advancement. According to this theory, Chinese culture was less developed than the West's in ancient times because bamboo (although abundance of materials is generally the primary reason for the use of bamboo as opposed to scientific prowess) was a clumsier writing material than papyrus; Chinese culture advanced during the Han Dynasty and preceding centuries due to the invention of paper; and Europe advanced during the Renaissance due to the introduction of paper and the printing press.
Paper remained a luxury item through the centuries, until the advent of steam-driven paper making machines in the 19th century, which could make paper with fibres from wood pulp. Although older machines predated it, the Fourdrinier paper making machine became the basis for most modern papermaking. Together with the invention of the practical fountain pen and the mass produced pencil of the same period, and in conjunction with the advent of the steam driven rotary printing press, wood based paper caused a major transformation of the 19th century economy and society in industrialized countries. Before this era a book or a newspaper was a rare luxury object and illiteracy was the norm for the majority. With the gradual introduction of cheap paper, schoolbooks, fiction, non-fiction, and newspapers became slowly available to nearly all the members of an industrial society. Cheap wood based paper also meant that keeping personal diaries or writing letters ceased to be reserved to a privileged few in those same societies. The office worker or the white-collar worker was slowly born of this transformation, which can be considered as a part of the industrial revolution.
Unfortunately, the original wood-based paper was more acidic and more prone to disintegrate over time, a process known as slow fires. Documents written on more expensive rag paper were more stable. The majority of modern book publishers now use acid-free paper.
Recent Developments
Paper made in the west since the industrial revolution has been almost exclusively wood based, except for a few specialist papers such as banknotes. However, at least one company (Cloudy Bay Cotton) has recently tried to introduce cotton based tissue papers to westernised countries as an alternative to wood based ones. Their reasons for doing this are that the cotton based tissue papers are less abrasive, less likely to cause allergic reactions, and far more environmentally beneficial than wood papers, being made from renewable materials (the type of cotton fibres used for making paper are in fact discarded as unusable waste from the textile industry) and requiring less chemical and energy intensive processing during manufacture.
Some manufacturers, notably AMD, have started using a new, environmentally friendly alternative to expanded plastic packaging made out of paper, known commercially as "paperfoam". The packaging has very similar mechanical properties to some expanded plastic packaging, but is biodegradable and can also be recycled with ordinary paper.
See also
- Electronic_paper
- Kaolin
- newspaper
- cardboard
- crêpe
- foxing
- ISO 216
- newsprint
- paper sizes
- paper mill
- paper recycling
- pulp and paper industry
- read or die
- stationery
- substrate (printing)
- washi
External links
- "How is paper made?" at The Straight Dope, 22 November 2005
- No End to Paperwork
- History of Paper and Papermaking
- Paper Online
- How Paper Is Made
- United States Government Printing Office: Government Paper Specification Standards
- Interactive Paper
- Magic Material Paper
- History of Paper Making