Friday, December 21, 2007

Nanotechnology

Nanotechnology is a field of applied science and technology casing a broad range of topics. The main unifying theme is the control of matter on a scale smaller than 1 micrometre, normally in the order of 1 to 100 nanometers, as well as the fabrication of plans of this size. It is a highly multidisciplinary field, drawing from fields such as functional physics, materials science, colloidal science, appliance physics, supramolecular chemistry, and even mechanical and electrical engineering. Much speculation exists as to what new discipline and technology may result from these lines of research. Nanotechnology can be seen as an extension of accessible sciences into the nanoscale, or as a recasting of existing sciences using a newer, most recent term.

Two main approaches are used in nanotechnology. In the bottom-up approach, materials and devices are built from molecular mechanisms which assemble themselves chemically by principles of molecular appreciation. In the top-down approach, nano-objects are constructed from larger entities without atomic-level power. The impetus for nanotechnology comes from a renewed attention in colloidal science, coupled with a new invention of analytical tools such as the minute force microscope, and the scanning tunneling microscope (STM). Combined with refined processes such as electron beam lithography and molecular beam epitaxy, these instruments allow the purposeful manipulation of nanostructures, and led to the observation of novel phenomena.

Monday, December 17, 2007

Inductor

An inductor is a passive electrical device working in electrical circuits for its property of inductance. Inductance is an consequence which results from the magnetic field that forms around a current carrying conductor. Electrical current through the conductor creates a magnetic flux relative to the current. A change in this current creates a change in magnetic flux that, in turn, generates an electromotive force that acts to oppose this change in current. Inductance is a calculate of the generated emf for a unit modify in current. An inductor with an inductance of 1 henry produces an emf of 1 V when the current through the inductor changes at the rate of 1 ampere per second. The number of turns, the area of each loop/turn, and what it is wrapped around influence the inductance.

An inductor opposes changes in the current. An ideal inductor would offer no resistance to a constant direct current, however, only superconducting inductors have truly zero electrical resistance. Inductors are used expansively in analog circuits and signal processing.

Thursday, November 29, 2007

Doomguy

The doomguy, also known as Doom Dude, Doom or The Marine, is the character of the Doom series of computer and video games formed by id Software. In all the games, he is a space marine working for the Union Aerospace Corporation (UAC), who never speaks and is by no means referred to by name.
In the Doom novels, the main quality is referred to as Flynn Fly Taggart, which is universally suggested to be the Doomguy from the games. However, Tom Hall's original design draft, also known as Doom Bible, recommended his name was Buddy Dacote. In the Doom film revision, the main character, John Reaper Grimm is also suggested to be the Doomguy. This is a twist because the audience likely expects Sarge to acquire that role.
All of the computer-game renditions of the Doomguy dress in green armour. Reaper from the film story wears combat gear reminiscent of a S.W.A.T. operative.

Thursday, November 22, 2007

Tourism

Tourism is traveling for the most part fun or vacation purposes. According to the World Tourism association, tourists are public who "travel to and stay in places outside their usual location for not more than one repeated year for vacation, business and other purposes not related to the use of an activity compensated from within the place visited". Tourism has happen to a very popular, overall activity. In 2004, there were over 763 million international tourist arrivals. Major physical elements include transportation, lodging, and other components of a hospitality industry.

Tourism is very important for many countries, due to the earnings generated by the spending of supplies and services by tourists, the assessment levied on businesses in the tourism industry, and the opportunity for employment and financial development by working in the industry. For these reasons, NGOs and government agencies may sometimes sponsor a specific area as a tourist intention, and support the development of a tourism industry in that area.

Tuesday, October 30, 2007

Biography

Biography is a type of literature and further forms of media such as film, based on the written accounts of individual lives. While a biography may focus on a subject of fiction or non-fiction, the term is frequently in reference to non-fiction. Pat Shipman however, says "I think a good biographer has to write fiction some of the time to make apparent a significant event in someone's life." This is sometimes debated. As opposed to a profile or curriculum vitae, a biography develops a complex analysis of personality, highlighting different aspects of it and including intimate details of experiences. A biography is more than a list of distant facts like birth, education, work, relationships and death. It also delves into the emotions of experiencing such events.

Ancient Greeks developed the biographical tradition which we have inherited, although until the 5th century AD, when the word biographia first appears, in Damascius Life of Isodorus , biographical pieces were called simply "lives". It is quite likely that the Greeks were drawing on a pre-existing eastern tradition; certainly Herodotus' Histories contains more exhaustive biographical information on Persian kings and subjects than on anyone else, implying he had a Persian source for it.

Monday, October 22, 2007

Calculator

A calculator is a machine for performing calculations. Although modern calculators often incorporate a general purpose computer, the device is calculated for performing specific operations, rather than for flexibility. Modern calculators are more convenient than most computers, though some Pads are comparable in amount to handheld calculators.

In the past, some calculators were as huge as today's computers. The first automatic calculators were mechanical desktop devices which were replaced by electromechanical desktop calculators, and then by electronic devices using first sung valves, then transistors, then hard-wired integrated circuit logic. New calculators are electrically powered and come in innumerable shapes and sizes varying from cheap, give-away, credit-card sized models to more sturdy adding machine-like models with built-in printers.

Friday, October 12, 2007

Rainbows

Rainbows can be practical whenever there are water drop in the air and sunlight shining from behind the observer at a low altitude or angle. The most spectacular rainbow displays when half of the sky is still dim with draining clouds and the observer is at a spot with clear sky overhead. The rainbow effect is also commonly seen near waterfalls or fountains. Rainbow fringes can sometimes be seen at the edges of backlit clouds and as vertical bands in far rain or virga. The effect can also be artificially created by dispersing water droplets into the air during a sunny day. Rarely, a moonbow, lunar rainbow or night-time rainbow, can be seen on stoutly moonlit nights. As human visual observation for colour is poor in low light, moonbows are most often perceived to be white.
The rainbow's exterior is caused by dispersion of sunlight as it goes through raindrops. The light is first refracted as it enters the surface of the raindrop, reflected off the back of the drop, and over refracted as it leaves the drop. The overall effect is that the incoming light is reflected back over a wide range of angles, with the most intense light at an angle of 40°–42°. The angle is self-determining of the size of the drop, but does depend on its refractive index. Seawater has a higher refractive index than rain water, so the radius of a 'rain'bow in sea spray is smaller than a true rainbow. This is visible to the naked eye by a misalignment of these bows.

Monday, September 24, 2007

Safety

Safety is the state of being safe, the situation of being protected against physical, social, spiritual, financial, political, emotional, occupational, psychological, educational or additional types or consequences of failure, damage, error, accidents, harm or any other event which could be considered non-desirable. This can take the form of being protected from the event or from exposure to something that causes health or reasonable losses. There also are two slightly different meanings of safety, a safety home may indicate its protection ability against external harm events, and the second that its internal installations are safe for its habitants.
Safety can be limited in relative to some guarantee or a standard of insurance to the quality and unharmful function of an object or organization. It is used in order to ensure that the object or association will do only what it is meant to do. Normative safety is a term used to explain products or designs that meet applicable design standards. Substantive safety stands for that the real-world safety history is favorable, whether or not standards are met. Perceived safety refers to the stage of comfort of users.

Thursday, September 13, 2007

Table

In relational databases, SQL databases, and flat file databases, a table is a set of data elements that is controlled using a model of horizontal rows and vertical columns. The columns are identified by name, and the rows are identified by the values appearing in a particular column division which has been identified as a candidate key. Table is another term for family although there is the difference in that a table is usually a multi-set of rows whereas a relation is a set and does not allow duplicates. A table has a particular number of columns but can have any number of rows. Besides the actual data rows, tables generally have related with them some meta-information, such as constraints on the table or on the values within particular columns.

The data in a table does not have to be actually stored in the database. Views are also relational tables, but their data is considered at query time. In non-relational systems, such as hierarchical databases, the isolated counterpart of a table is a structured file, representing the rows of a table in each record of the file and each column in a record.

Friday, August 31, 2007

Tsunami

A tsunami is a series of waves shaped when a body of water, such as an ocean, is rapidly displaced. Earthquakes, group movements above or below water, volcanic eruptions and other underwater explosions, landslides, large meteorite impacts and testing with nuclear weapons at sea all have the potential to produce a tsunami. The effects of a tsunami can range from imperceptible to devastating. The word tsunami comes from the Japanese words meaning harbor and wave. For the plural, one can either follow usual English practice and add an s, or use an invariable plural as in Japanese. The term was created by fishermen who returned to port to find the area neighboring their harbor devastated, although they had not been conscious of any wave in the open water. Tsunamis are general throughout Japanese history; approximately 195 events in Japan have been recorded.
A tsunami has a much smaller amplitude (wave height) offshore, and a very long wavelength, which is why they generally pass unobserved at sea, forming only a passing bulge in the ocean. Tsunami have been historically referred to as tidal waves because as they approach land, they take on the characteristics of a vicious onrushing tide rather than the sort of cresting waves that are formed by wind action upon the ocean. Since they are not really related to tides the term is considered misleading and its treatment is discouraged by oceanographers.

Monday, August 20, 2007

Populations

Populations are studied, in exacting, in a branch of ecology known as population biology, and in population genetics. In population dynamics, size, age and sex structure, mortality, reproductive behavior, and development of a population are studied. In biology, an isolated population denotes a breeding group whose members breed mostly or solely among themselves, usually as a result of physical isolation, although biologically they could breed with any members of the varieties. If there are several completely or nearly completely secluded populations in the global population of a taxon, these are called subpopulations. The Metapopulation is a network of subpopulations in a given area, where the individuals of the various subpopulations are able to cross dilapidated areas of the region. Biological dispersal is one of the key elements upsetting such populations; if dispersal is sufficiently low for a prolonged period of time, speciation is likely to be a consequence.
Population growth is varying in population over time. It also can be quantified as the change in the number of individuals in a population per piece time. The term population growth can technically refer to any species, but almost always refers to humans, and it often used easily for the more specific demographic term population growth rate, and is often used to refer specifically to the expansion of the population of the world.

Friday, August 10, 2007

River

A river is a natural waterway that transits water through a setting from higher to lower elevations. A river may have its basis in a spring, lake, from damp, boggy landscapes where the soil is waterlogged, from glacial melt, or from surface runoff of precipitation. Almost each and every one river is joined by other rivers and streams termed tributaries the highest of which are known as headwaters. Water may also begin from groundwater sources. Throughout the course of the river, the total volume transported downstream will often be a combination of the free water flow together with a important contribution flowing through sub-surface rocks and gravels that underlie the river and its floodplain. For many rivers in large valleys, this unseen component of flow may greatly go above the visible flow.
From their source, all rivers flow downhill, typically terminating in the sea or in a lake, through a confluence. In arid areas rivers sometimes end by losing water to desertion. River water may also infiltrate into the soil or pervious rock, where it becomes groundwater. Excessive abstraction of water for use in commerce, irrigation, etc., can also cause a river to dry before success its natural terminus.

Tuesday, July 31, 2007

Market

A market is a social arrangement that allows buyers and sellers to discover in sequence and carry out a voluntary replace of goods or services. It is one of the two key institutions that organize trade, along with the right to own goods. In everyday usage, the word market may refer to the place where goods are traded, sometimes known as a marketplace, or to a street market.

In economics a financial market is a device that allows people to easily buy and sell financial securities, commodities, and other fungible substance of value at low transaction costs and at prices that reflect capable markets. A stock market is a market for the trading of company stock, and derivatives of same; both of these are securities scheduled on a stock replace as well as those only traded privately.

Tuesday, July 24, 2007

Resistance

Electrical resistance is a compute of the degree to which an object opposes an electric current through it. The SI unit of electrical resistance is the ohm. Its reciprocal quantity is electrical conductance calculated in siemens. Electrical resistance shares some conceptual parallels with the mechanical notion of friction.

The resistance of an object determines the amount of current through the object for a known voltage across the object I=V/R, where R is the resistance of the object, measured in ohms, equivalent to J•s/C2, V is the voltage across the object, measured in volts, I is the current through the object, measured in amperes. In metals, the Fermi level lies in the conduction band giving rise to free transfer electrons. However, in semiconductors the position of the fermi level is within the band gap, closely half way between the conduction band minimum and valence band maximum for intrinsic semiconductors.

Wednesday, July 18, 2007

Security

Security is the condition of being sheltered against danger or loss. In the general sense, security is a perception similar to safety. The nuance between the two is an added emphasis on being protected from dangers that initiate from outside. Individuals or actions that encroach upon the condition of protection are responsible for the breach of security.

The word security in general procedure is synonymous with safety, but as a technical term security means that something not only is protected but that it has been secured. A condition that results from the establishment and maintenance of protective measures that ensures a state of inviolability from hostile acts or influences. With respect to classified matter, the condition that prevents unauthorized persons from having right to use to official information that is safeguarded in the benefit of national security.

Thursday, July 12, 2007

Computer file

A computer file is a block of subjective information, or resource for storing information, that is available to a computer program and is usually based on some kind of durable storage. A file is durable in the intelligence that it remains available for programs to use after the current program has finished. Computer files can be considered as the up to date counterpart of paper documents which traditionally were kept in offices and libraries files.

In most computer files are stored on various type of data storage device, there is a hard disk, from which most operating systems run and on which most store their files. Hard discs are the most ever-present form of non-volatile storage at the start of the 21st century. Where files have only temporary information, they may be stored in RAM. The way a computer organizes, names stores and manipulates files is worldwide referred to as its file system. Nearly all computers have at least one file system.

Thursday, July 05, 2007

Peacock

Peacock Lane is a 5 block street in Portland, Oregon which is notable because all of the houses are required to be adorned at Christmastime. During this instance, many people drive from all over the Portland area to view the decorated houses.The community has a website that has on its 1920s, each house in this quaint southeast locality has been decorating for Christmas. Mostly Tudors, the houses are adorned with not only beautiful stunning lights, but also nativity scenes, rotating Christmas trees and attractively life-like replicas of Santa and Frosty. This is a very popular Portland tradition and the crowds can get rather thick. It is wise to park several blocks away and walk, rather than drive from side to side the area. Better yet, take a ride in a horse-drawn carriage.

Wednesday, June 27, 2007

Vehicles

Vehicles are non-living means of moving. They are most repeatedly man-made (e.g. bicycles, cars, motorcycles, trains, ships, and aircraft), although some other means of transportation which are not made by man can also be called vehicles; examples include icebergs and balanced tree trunks. Vehicles may be propelled by animals, e.g. a chariot or an ox-cart. However, animals on their own, though used as a earnings of transportation, are not called vehicles. This includes humans transport another human, for example a child or a disabled person.

Vehicles that do not pass through on land are often called crafts, such as watercraft, sail craft, aircraft, hovercraft and spacecraft. Movement lacking the help of a vehicle or an animal is called locomotion. The word vehicle itself comes from the Latin vehicular.

Tuesday, June 19, 2007

Voltage

Voltage is the difference of electrical potential between two points of an electrical or electronic circuit, uttered in volts. It measures the potential energy of an electric field to source an electric current in an electrical conductor. Depending on the difference of electrical potential it is called extra low voltage, low voltage, high voltage or extra high voltage.

Between two points in an electric field, such as exists in an electrical circuit, the distinction in their electrical potentials is known as the electrical potential difference. This difference is proportional to the electrostatic force that tends to drive electrons or other charge-carriers from one point to the other. Potential difference, electrical potential, and electromotive force are measured in volts, leading to the commonly used term voltage. Voltage is usually represented in equations by the symbols V, U, or E.

Electrical potential difference can be thought of as the capacity to move electrical charge through a resistance. At a time in physics when the word force was used loosely, the potential difference was named the electromotive force or EMF—a term which is still used in confident contexts.

Thursday, June 07, 2007

Anatomical basics of the human lip

One differentiates between the Upper and lower lip. The lower lip is usually somewhat larger. The border between the lips and the surrounding skin is referred to as the vermilion border, or simply the vermilion. The vertical groove on the upper lip is known as the philtrum.

The skin of the lip, with three to five cellular layers, is very thin compared to typical face skin, having up to 16 layers. With light skin color, the lip skin contains no melanocyte. Because of this, the blood vessels appear through the skin of the lips, which leads to their notable red coloring. With darker skin color this effect is less prominent, as in this case the skin of the lips contains more melanin and thus is visually thicker.

The lip skin is not hairy and does not have sweat glands or sebaceous glands. Therefore, it does not have the usual protection layer of sweat and body oils which keep the skin smooth, kill pathogens, and regulate warmth. For these reasons, the lips dry out faster and become chapped more easily.

Tuesday, May 01, 2007

flag

A flag is a piece of woven cloth, often flown from a pole or mast, generally used symbolically for signalling or identification. The term flag is also used to refer to the graphic design employed by a flag, or to its depiction in another medium.
The first flags were used to assist military coordination on battlefields and flags have evolved into a general tool for rudimentary signalling and identification, especially in environments where communication is similarly challenging (such as the maritime environment where semaphore is used). National flags are potent patriotic symbols with varied wide-ranging interpretations, often including strong military associations due to their original and ongoing military uses. Flags are used in messaging, advertising, or for other decorative purposes, though at this less formal end the distinction between a flag and a simple cloth banner is blurred. The study of flags is known as vexillology, from the Latin vexillum meaning flag or banner.

Monday, April 30, 2007

Morality

Under some political views, activities funded by taxes can be beneficial to society and progressive taxation can be used in modern countries to provide an overall benefit to the majority of the population and social justice. Because payment of tax is compulsory and enforced by the police and justice system through what some libertarians view as institutionalized violence, libertarians consider taxation to be equivalent to theft, accusing the government of levying taxes via coercive means. Libertarians, individual anarchists, and anarcho-capitalists, see taxation as government aggression (see Zero Aggression Principle). The libertarian writer Jason C. Reeher echoed the sentiments of Murray Rothbard on these grounds; in criticizing his local school district's relatively small property tax increase, Reeher said that "(t)he thief who steals the least is still a thief." Some libertarians recommend a minimal level of taxation in order to maximize the protection of liberty, while others prefer market alternatives such as private defense agencies and arbitration agencies or voluntary contributions.
One counter-argument is that because the government is the party performing the act of imposing taxes, and assuming the existence of a democracy, society as a whole decides how the tax system should be organised. The American Revolution's "No taxation without representation" slogan implied this view. The same argument could be made in a monarchy: "since the King embodies the nation, the nation as a whole decides how the tax system should be organised." Substituting the terms "Politburo," "Führer," or "Leader," etc., for the word "King," one can describe the politics of most of the 20th century. Under this view, taxes are paid individually and therefore, to be considered voluntary, in any meaningful way, should be levied only with the consent of the individual.

TEACHING

Teachers need the ability to understand a subject well enough to convey its essence to a new generation of students. The goal is to establish a sound knowledge base on which students will be able to build as they are exposed to different life experiences. The passing of knowledge from generation to generation allows students to grow into useful members of society. Good teachers are able to translate information, good judgment, experience, and wisdom into a significant knowledge of a subject that is understood and retained by the student.

Monday, April 02, 2007

Bankruptcy

Bankruptcy is a lawfully affirmed incapability or impairment of ability of an individual or organization to pay their creditors. Creditors may file bankruptcy for a debtor in an effort to recoup a portion of what they are owed. In the most of the cases, bankruptcy is initiated by the debtor.

The main reason of bankruptcy is to give an honest debtor a fresh start in life by reducing the debtor of most debts, and to repay creditors in an orderly manner to the extent that the debtor has the means available for payment. Bankruptcy allows debtors to resolve debts through the division of non-exempt assets among creditors. In addition the declaration of bankruptcy allows debtors to be discharge most of the financial obligations, after their non exempt assets are dispersed, even if their debts have not been paid in full.

Monday, February 05, 2007

Personal property

Personal property is a sort of property. In the common law systems personal property may also be described has chattels. It is distinguished from real property, or real estate. In civil law systems personal property is can be called as movable property or movables, any property that can be moved from one location to another. This term is in distinction with immovable property or immovable, such as land and buildings.

The distinction between these kinds of property is important for a variety of reasons. Generally one's rights on movables are more attenuated than one's rights on immovable. The statutes of restrictions or prescriptive periods are usually shorter when trading with personal or movable property. Real property rights are usually enforceable for a longer period and in most jurisdictions real estate and immovable are registered in government sanctioned land registers. In some jurisdictions, rights can be registered against personal or movable property.

Saturday, January 13, 2007

Population policy in China

With a population of over 1.3 billion, the PRC is very worried about its population growth and has attempted with mixed results to implement a strict family planning policy. The government's goal is one child per family, with exceptions for ethnic minorities and flexibility in rural areas, where a family can have a second child if the first is a girl or physically disabled. The government's goal is to steady population growth early in the 21st century, though some current projections estimate a population of anywhere ranging from 1.4 billion to 1.6 billion by 2025.