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.
Friday, December 21, 2007
Tsunami
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, December 17, 2007
Resistance
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.
Thursday, November 29, 2007
space shuttle
The Shuttle is the first orbital spacecraft considered for partial reusability. It carries large payloads to various orbits, provides crew rotary motion for the International Space Station (ISS), and performs servicing missions. The orbiter can also recover satellites and other payloads from orbit and return them to Earth, but this capability has not been used often. However, it has been used to return large payloads from the ISS to Earth, as the Russian Soyuz spacecraft has limited capacity for return payloads. Each Shuttle was designed for a expected lifespan of 100 launches or 10 years' operational life.
Thursday, November 22, 2007
Entertainment
While people have laughing themselves since the beginning of time, the entertainment industry first became a leading force in culture in the 20th century with the development of latest electronic technologies of recording and spreading. Western peoples, tired of serious purposes and gathering massacre, turned to popular culture following the two world wars. The financial basis of this new culture was advertising of free or inexpensive entertainment program. In their peak, television networks were great selling machines which, besides entertaining people, prohibited both commercial and political markets by providing direct access to the group of customers. This "territory" is now in danger by the explosion and segmentation of media and especially by the growing importance of communication by computer which allows the consumer to look for out the informational message as an alternative of having it broadcast to him or her. A new system of world history sees Americans in changeover between a fourth, entertainment-based "society" and a future fifth evolution based on computer communication.
Tuesday, October 30, 2007
Blue tooth
Blue tooth is a radio standard and communications protocol mostly designed for low power consumption, with a short range based on low-cost transceiver microchips in each device. The devices use a radio communications system, so they do not have to be in line of view of each other, and can even be in other rooms, as long as the conservative transmission is powerful enough.
Monday, October 22, 2007
Hockey
Hockey is any of a family of sports in which two teams struggle by trying to maneuver a ball, or a hard, surrounding disc called a puck, into the opponent's net or goal, using a hockey stick. Field hockey is played on nettle, natural grass, sand-based or water-based artificial turfs, with a small, hard ball. The game is popular among both males and females in many countries of the world, mostly in Europe, India, Pakistan, Australia, New Zealand, South Africa and South Asia. In most countries, the game is played between single-sex sides, even though it can be played by mixed-sex sides. In the United States and Canada it is played mostly by women. Ball hockey is played in a gym using sticks and a ball, often a tennis ball with the hair removed.
Friday, October 12, 2007
Race
Since the 1940s, some evolutionary scientists have rejected the view of race as a biologically meaningful impression. A majority of evolutionary scientists reject the notion that any definition of race pertaining to humans can have any taxonomic rigour and validity. Mainstream scientists have argued that race definition are imprecise, arbitrary, derived from custom, have many exceptions, have many gradations, and that the numbers of races experimental vary according to the culture examined. They further preserve that race as such is best understood as a social construct.
Monday, September 24, 2007
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, September 13, 2007
Planet
The energetic impacts of the smaller planetesimals will heat up the increasing planet, causing it to at least partially melt. The interior of the planet begins to differentiate by mass, mounting a denser core. Smaller terrestrial planets lose most of their atmospheres because of this accretion, but the lost gases can be replaced by out gassing from the mantle and from the succeeding impact of comets.
Friday, August 31, 2007
Earthquake
Monday, August 20, 2007
Cloud
On Earth the condensing matter is typically water vapor, which forms small droplets or ice crystals, typically 0.01 mm in diameter. When surrounded by billions of other droplets or crystals they become observable as clouds. Dense deep clouds exhibit a high reflectance throughout the visible range of wavelengths: they thus appear white, at least from the top. Cloud droplets tend to scatter light professionally, so that the intensity of the solar radiation decreases with depth into the cloud, hence the gray or even sometimes dark exterior of the clouds at their base. Thin clouds may appear to have acquired the color of their environment or background, and clouds illuminated by non-white light, such as through sunrise or sunset, may be colored accordingly. In the near-infrared range, clouds would appear darker because the water that constitutes the cloud droplets muscularly absorbs solar radiation at those wavelengths.
Friday, August 10, 2007
Inca Rope bridge
The construction of these bridges amounted to a pair of stone anchors on each side of the canyon with immense cables of woven ichu grass linking these two pylons together. Adding to this construction, two additional cables acted as guardrails. The cables which supported the foot-path were unbreakable with plaited branches. This multi-structure system made these bridges strong enough to even carry the Spaniards while riding horses after they indoors. However, these massive bridges were so heavy that they tended to sag in the middle, and this caused them to bend in high winds.
Tuesday, July 31, 2007
Calculator
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 thermionic 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.
Tuesday, July 24, 2007
Indicator
An economic indicator is a statistic concerning the economy. The lighting system of a motor vehicle consists of lighting and signaling procedure mounted or integrated to the front, sides and rear of the vehicle. The purpose of this system is to present illumination for the driver to operate the vehicle safely after dark, to increase the visibility of the vehicle, and to display information about the vehicle's presence, position, size, direction of travel, and driver's intentions concerning direction and speed of travel.
Wednesday, July 18, 2007
Reliability
Reliable protocols normally incur more overhead than unreliable protocols, and as a result, are slower and less scalable. This often isn't an issue for unicast protocols, but it may be a difficulty for multicast protocols. TCP, the main protocol used in the Internet today, is a reliable unicast protocol. UDP, often used in computer games or other situation where speed is an issue and the loss of a little fact is not, is an unreliable unicast protocol.
Thursday, July 12, 2007
Table
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.
Thursday, July 05, 2007
Trams
Wednesday, June 27, 2007
Health
Health is the level of functional and metabolic effectiveness of an organism at both the micro and macro level. In the medical field, health is commonly defined as an organism's skill to efficiently respond to challenges and effectively restore and maintain a state of balance, known as homeostasis.
Wednesday, June 20, 2007
Color
Color is the visual perceptual possessions corresponding in humans to the categories called red, yellow, white, etc. Color derives from spectrum of light distribution of light energy versus wavelength interacting in the eye with the spectral sensitivities of the light receptors. Color categories and physical condition of color are also associated with objects, materials, light sources, etc., based on their physical properties such as light absorption, reflection, or emission spectra.
Typically, only features of the composition of light that are visible by humans wavelength spectrum from 400 nm to 700 nm, roughly are included, thereby objectively relating the psychological phenomenon of color to its physical specification. Because perception of color stems from the varying sensitivity of different types of cone cells in the retina to different parts of the spectrum, colors may be defined and quantify by the degree to which they stimulate these cells. These physical or physiological quantifications of color, however, do not fully clarify the psychophysical perception of color appearance.
The science of color is sometimes called chromatics. It includes the perception of color by the human eye and brain, the origin of color in materials, color theory in art, and the physics of electromagnetic emission in the visible range that is, what we commonly refer to simply as light.
Thursday, June 07, 2007
Cosmetics
Tuesday, May 01, 2007
Flag
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
Tax
In modern capitalist taxation systems, taxes are levied in money, but in-kind and corvée taxation are characteristic of traditional or pre-capitalist states and their functional equivalents. The method of taxation and the government expenditure of taxes raised is often highly debated in politics and economics. Tax collection is performed by a government agency such as Revenue Canada, the Internal Revenue Service (IRS) in the United States, or Her Majesty's Revenue and Customs (HMRC) in the UK. When taxes are not fully paid, civil penalties (such as fines or forfeiture) or criminal penalties (such as incarceration)[3] may be imposed on the non-paying entity or individual.
Deerhabitat
Monday, April 02, 2007
Debenture
The benefit of debentures to the issuer is they leave specific assets tangential, and thereby leave them open for subsequent financing.
Monday, February 05, 2007
Foreclosure
In US, there are two kinds of foreclosure in common law states. Using a deed in lieu of foreclosure, the bank claims the title and possession of the property back in full satisfaction of a debt, usually on contract. Many states needs the latter sort of proceeding in some or all cases of foreclosure, in order to protect any equity the debtor may have in the property, in case the value of the debt being foreclosed on is significantly less than the market value of the immovable assets.
Saturday, January 13, 2007
Political divisions of China
The twenty-two provinces, five autonomous regions and four municipalities can be jointly referred to as "mainland China", a term which usually excludes Hong Kong and Macau.