TECHNOLOGY

Technology is a broad concept that deals with an animal species' usage and knowledge of tools and crafts, and how it affects an animal species' ability to control and adapt to its environment. Technology is a term with origins in the Greek "technologia", "τεχνολογία" — "techne", "τέχνη" ("craft") and "logia", "λογία" ("saying"). [1] However, a strict definition is elusive; "technology" can refer to material objects of use to humanity, such as machines, hardware or utensils, but can also encompass broader themes, including systems, methods of organization, and techniques. The term can either be applied generally or to specific areas: examples include "construction technology", "medical technology", or "state-of-the-art technology".
The human race's use of technology began with the conversion of natural resources into simple tools. The prehistorical discovery of the ability to control fire increased the available sources of food and the invention of the wheel helped humans in travelling in and controlling their environment. Recent technological developments, including the printing press, the telephone, and the Internet, have lessened physical barriers to communication and allowed humans to interact freely on a global scale. However, not all technology has been used for peaceful purposes; the development of weapons of ever-increasing destructive power has progressed throughout history, from clubs to nuclear weapons.
Technology has affected society and its surroundings in a number of ways. In many societies, technology has helped develop more advanced economies (including today's global economy) and has allowed the rise of a leisure class. Many technological processes produce unwanted by-products, known as pollution, and deplete natural resources, to the detriment of the Earth and its environment. Various implementations of technology influence the values of a society and new technology often raises new ethical questions. Examples include the rise of the notion of efficiency in terms of human productivity, a term originally applied only to machines, and the challenge of traditional norms.
Philosophical debates have arisen over the present and future use of technology in society, with disagreements over whether technology improves the human condition or worsens it. Neo-Luddism, anarcho-primitivism, and similar movements criticise the pervasiveness of technology in the modern world, claiming that it harms the environment and alienates people; proponents of ideologies such as transhumanism and techno-progressivism view continued technological progress as beneficial to society and the human condition. Indeed, until recently, it was believed that the development of technology was restricted only to human beings, but recent scientific studies indicate that other primates and certain dolphin communities have developed simple tools and learned to pass their knowledge to other generations.

See More

Science, engineering and technology

The distinction between science, engineering and technology is not always clear. Science is the reasoned investigation or study of phenomena, aimed at discovering enduring principles among elements of the phenomenal world by employing formal techniques such as the scientific method. [8] Technologies are not usually exclusively products of science, because they have to satisfy requirements such as utility, usability and safety.
Engineering is the goal-oriented process of designing and making tools and systems to exploit natural phenomena for practical human means, often (but not always) using results and techniques from science. The development of technology may draw upon many fields of knowledge, including scientific, engineering, mathematical, linguistic, and historical knowledge, to achieve some practical result.
Technology is often a consequence of science and engineering — although technology as a human activity precedes the two fields. For example, science might study the flow of electrons in electrical conductors, by using already-existing tools and knowledge. This new-found knowledge may then be used by engineers to create new tools and machines, such as semiconductors, computers, and other forms of advanced technology. In this sense, scientists and engineers may both be considered technologists; the three fields are often considered as one for the purposes of research and reference. [9]
The exact relations between science and technology in particular have been debated by scientists, historians, and policymakers in the late 20th century, in part because the debate can inform the funding of basic and applied science. In immediate wake of World War II, for example, in the United States it was widely considered that technology was simply "applied science" and that to fund basic science was to reap technological results in due time. An articulation of this philosophy could be found explicitly in Vannevar Bush's treatise on postwar science policy, Science—The Endless Frontier: "New products, new industries, and more jobs require continuous additions to knowledge of the laws of nature... This essential new knowledge can be obtained only through basic scientific research." In the late-1960s, however, this view came under direct attack, leading towards initiatives to fund science for specific tasks (initiatives resisted by the scientific community). The issue remains contentious—though most analysts resist the model that technology simply is a result of scientific research.

for more detail

The Scope of Technology

It seems that more and more, the term "technology" is used to refer only to computer technology. For our class, examples of computer technology are very appropriate, but please feel free to expand that notion of technology to include a wider variety, such as: medical technologies; military technologies; agricultural technologies; historical and futuristic (even science-fiction) technologies; material processing technologies; and household technologies

Levels of Technology

There is a personal level, which is distinct from, say, a corporate level, a national level, or a global level. But they are related; how a nation uses petroleum is clearly related to how an individual uses petroleum, but different strategies are often required to both study and effect changes at these levels.
There may be a tendency in our class to look at "using technology" at the level of the individual, and "technology assessment" at a corporate, regional, national, or international level. But this need not be the case.
Let's just be clear about what we mean. If you are using technology to refer to a piece high-tech hospital equipment and I use it to refer to my computer, and someone else uses it to refer to the global referring to global transportation infrastructure, then communication could be a problem

Modeling Technology

There are many other ways to divide up technological actions. For twenty years the International Technology Education Association promoted dividing it into Manufacturing, Construction, Communication, and Transportation. Or we could look at technology as a type of processing, dividing into Information Processing, Energy Processing, and Material Processing. As a materials science teacher, I commonly use Procurement, Transformation, Utilization, and Disposition as organizers for the study of material-related technologies.
But one problem common to traditional views of technology is a lack of attention to the interconnectedness within and extending outside of a system. For example, one typical model that is used to represent any dynamic system has sometimes been called the Universal Systems Model (what an arrogant title.) It involves Input, Process, and Output (IPO), with feedback that flows in the opposite direction. But there is no connection to other systems, and the IPO model is linear, with starting and ending points. That just doesn't seem realistic.
For example, to build a guitar, we need 3 board feet (I'm guessing) of Brazilian Rosewood, among other things. Typical processes are sawing, gluing, and finishing. The outputs include the guitar and wood chips. But this model has no way to look at where the rosewood came from, or if it should have been harvested in the first place. It doesn't look at the history the precedes inputs, nor the consequences that may be distant. Is one of the outputs of Indiana's coal-fired generators dead fish in New York? I wouldn't say so, but I would call it one of the impacts.
But typically, we are more concerned with process than with implications or impacts. Learning a process might be a short-term need, and we may not have the guts to take a broader view.
Stephen Petrina, at the University of British Columbia, adapted a catch phrase on his web site related to technology: "Think globally, act locally" was the phrase, adapted to "Think globally, act globally, think locally, act locally."

Issues Concerning the Use of Technology

The study of "using technology" includes historical methods, clinical experiments, surveys of users or potential users, the usability testing of products, the design of environments and devices to promote "userfriendliness," and a host of other areas.

Typical questions one might raise concerning use are:

• Is this the best product for the task?
  
• How do we help people learn how to use this technology?
  
• Does it fit the human body?
  
• Should we use this technology?
  
• What technologies can be used to meet special needs?
  
• How durable is the technology?
  
• How can this item be redesigned to improve usability?
  
• Is the technology supported sufficiently (by technical backing, not by cast iron legs)?
  
• Is the technology cost effective?
  
• What is the break even period for this technological adoption?
  
• What are user's beliefs about this technology?
  
• What are the psychological factors involved in the human interface?
  
• What are the assumptions and implications of this technological adoption?

Issues related to Technology Assessment

Whenever anyone makes a judgment about a technology, that may be called a technology assessment. In the literature, especially that generated by the US Office of Technology Assessment, the term relates to a group of types of studies that look at technological options and policy issues.
Typically, a formal technology assessment is commissioned prior to a government's or corporation's decision to choose one technological path over another. Thus, it is the aim of the team of specialists preparing the technology assessment to objectively present a short list of realistic options or alternate decisions, and to spell out their best predictions about the consequences of each option.
An environmental impact statement may be a type of technology assessment, but there are many other types as well. Technology assessments can use a variety of tools, including benefit/cost analysis, trend extrapolation, opinion measurement, simulation models, and many others.
But even the most informal technology assessment may well be concerned with collecting information, analyzing the information, developing a list of possible scenarios, forecasting, and weighing technological tradeoffs. A company that uses pneumatic and hydraulic robot may wish to commission a technology assessment or feasibility study on the upgrade to servo robots. Before lawmakers enact legislation, they often use the report of a technology assessment. On the personal level, a car buyer carefully scrutinizes a variety of choices, and often uses the same decision-making as in formal technology assessments.
The purpose of technology assessment is to objectively inform a technological decision so as to minimize unwanted outcomes and maximize desired outcomes.

Electricity

Electricity (from the New Latin ēlectricus, "amber-like"[a]) is a general term that encompasses a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena such as lightning and static electricity, but in addition, less familiar concepts such as the electromagnetic field and electromagnetic induction.
In general usage, the word 'electricity' is adequate to refer to a number of physical effects. However, in scientific usage, the term is vague, and these related, but distinct, concepts are better identified by more precise terms:
Electric charge – a property of some subatomic particles, which determines their electromagnetic interactions. Electrically charged matter is influenced by, and produces, electromagnetic fields.
Electric current – a movement or flow of electrically charged particles, typically measured in amperes.
Electric field – an influence produced by an electric charge on other charges in its vicinity.
Electric potential – the capacity of an electric field to do work on a electric charge, typically measured in volts.
Electromagnetism – a fundamental interaction between the magnetic field and the presence and motion of an electric charge.
Electrical phenomena have been studied since antiquity, though advances in the science were not made until the seventeenth and eighteenth centuries. Practical applications for electricity however remained few, and it would not be until the late nineteenth century that engineers were able to put it to industrial and residential use. The rapid expansion in electrical technology at this time transformed industry and society. Electricity's extraordinary versatility as a source of energy means it can be put to an almost limitless set of applications which include transport, heating, lighting, communications, and computation. The backbone of modern industrial society is, and for the foreseeable future can be expected to remain, the use of electrical power

CONCEPTS

Electric Charge

Electric charge is a property of certain subatomic particles, which gives rise to and interacts with, the electromagnetic force, one of the four fundamental forces of nature. Charge originates in the atom, in which its most familiar carriers are the electron and proton. It is a conserved quantity, that is, the net charge within an isolated system will always remain constant regardless of any changes taking place within that system.[15] Within the system, charge may be transferred between bodies, either by direct contact, or by passing along a conducting material, such as a wire.[16] The informal term static electricity refers to the net presence (or 'imbalance') of charge on a body, usually caused when dissimilar materials are rubbed together, transferring charge from one to the other.

Charge on a gold-leaf electroscope causes the leaves to visibly repel each other
The presence of charge gives rise to the electromagnetic force: charges exert a force on each other, an effect that was known, though not understood, in antiquity.[17] A lightweight ball suspended from a string can be charged by touching it with a glass rod that has itself been charged by rubbing with a cloth. If a similar ball is charged by the same glass rod, it is found to repel the first: the charge acts to force the two balls apart. Two balls that are charged with a rubbed amber rod also repel each other. However, if one ball is charged by the glass rod, and the other by an amber rod, the two balls are found to attract each other. These phenomena were investigated in the late eighteenth century by Charles-Augustin de Coulomb, who deduced that charge manifests itself in two opposing forms. This discovery led to the well-known axiom: like-charged objects repel and opposite-charged objects attract.[17]
The force acts on the charged particles themselves, hence charge has a tendency to spread itself as evenly as possible over a conducting surface. The magnitude of the electromagnetic force, whether attractive or repulsive, is given by Coulomb's law, which relates the force to the product of the charges and has an inverse-square relation to the distance between them.[18][19] The electromagnetic force is very strong, second only in strength to the strong interaction,[20] but unlike that force it operates over all distances.[21] In comparison with the much weaker gravitational force, the electromagnetic force pushing two electrons apart is 1042 times that of the gravitational attraction pulling them together.[22]
The charge on electrons and protons is opposite in sign, hence an amount of charge may be expressed as being either negative or positive. By convention, the charge carried by electrons is deemed negative, and that by protons positive, a custom that originated with the work of Benjamin Franklin.[23] The amount of charge is usually given the symbol Q and expressed in coulombs;[24] each electron carries the same charge of approximately −1.6022×10−19 coulomb. The proton has a charge that is equal and opposite, and thus +1.6022×10−19 coulomb. Charge is possessed not just by matter, but also by antimatter, each antiparticle bearing an equal and opposite charge to its corresponding particle.[25]
Charge can be measured by a number of means, an early instrument being the gold-leaf electroscope, which although still in use for classroom demonstrations, has been superseded by the electronic electrometer.procedures, and the invention of new devices and equipment to aid those with health problems, physical disabilities, and sensory impairments, the latter third of the 20th century has borne witness to a very dramatic evolution. The current perspective is a broad one in which six types of technology are recognized: the technology of teaching, instructional technology, assistive technology, medical technology, technology productivity tools, and information technology (Blackhurst & Edyburn, 2000).

Electric current

The movement of electric charge is known as an electric current, the intensity of which is usually measured in amperes. Current can consist of any moving charged particles; most commonly these are electrons, but any charge in motion constitutes a current.
By historical convention, a positive current is defined as having the same direction of flow as any positive charge it contains, or to flow from the most positive part of a circuit to the most negative part. Current defined in this manner is called conventional current. The motion of negatively-charged electrons around an electric circuit, one of the most familiar forms of current, is thus deemed positive in the opposite direction to that of the electrons.[26] However, depending on the conditions, an electric current can consist of a flow of charged particles in either direction, or even in both directions at once. The positive-to-negative convention is widely used to simplify this situation.

An electric arc provides an energetic demonstration of electric current
The process by which electric current passes through a material is termed electrical conduction, and its nature varies with that of the charged particles and the material through which they are travelling. Examples of electric currents include metallic conduction, where electrons flow through a conductor such as metal, and electrolysis, where ions (charged atoms) flow through liquids. While the particles themselves can move quite slowly, sometimes with an average drift velocity only fractions of a millimetre per second,[16] the electric field that drives them itself propagates at close to the speed of light, enabling electrical signals to pass rapidly along wires.[27]
Current causes several observable effects, which historically were the means of recognising its presence. That water could be decomposed by the current from a voltaic pile was discovered by Nicholson and Carlisle in 1800, a process now known as electrolysis. Their work was greatly expanded upon by Michael Faraday in 1833.[28] Current through a resistance causes localised heating, an effect James Prescott Joule studied mathematically in 1840.[28] One of the most important discoveries relating to current was made accidentally by Hans Christian Ørsted in 1820, when, while preparing a lecture, he witnessed the current in a wire disturbing the needle of a magnetic compass.[29] He had discovered electromagnetism, a fundamental interaction between electricity and magnetics.
In engineering or household applications, current is often described as being either direct current (DC) or alternating current (AC). These terms refer to how the current varies in time. Direct current, as produced by example from a battery and required by most electronic devices, is a unidirectional flow from the positive part of a circuit to the negative.[30] If, as is most common, this flow is carried by electrons, they will be travelling in the opposite direction. Alternating current is any current that reverses direction repeatedly; almost always this takes the form of a sinusoidal wave.[31] Alternating current thus pulses back and forth within a conductor without the charge moving any net distance over time. The time-averaged value of an alternating current is zero, but it delivers energy in first one direction, and then the reverse. Alternating current is affected by electrical properties that are not observed under steady state direct current, such as inductance and capacitance.[32] These properties however can become important when circuitry is subjected to transients, such as when first energised