People are a group of humans, either with not mentioned traits, or specific characteristics (e.g. the people of Spain or the people of the Plains).
The term people is often used in English as the suppletive plural of person. However, the word persons is sometimes used in place of people, particularly when it would be ambiguous with its collective sense (e.g. missing persons instead of missing people). The term people can together refer to all humans or it can be used to identify the citizens of a nation, or members of a tribe, ethnic, or religious group. People of color is a phrase used to describe people with skin color darker than that of white people.
Thursday, May 31, 2007
Sunday, May 27, 2007
Veganism
Veganism (also known as strict vegetarianism or pure vegetarianism), as defined by the Vegan Society, is "a philosophy and way of living which seeks to exclude—as far as is possible and practical—all forms of exploitation of, and cruelty to, animals for food, clothing or any other purpose." A vegan (one who practices veganism) does not consume or use animal products, notably meat, fish, poultry, eggs and dairy products.People become vegans for a variety of reasons, including ethical concerns for animal rights or the environment, as well as supposed or real health benefits and spiritual or religious concerns.
Monday, May 21, 2007
Lighting rod
A lightning rod is a metal narrow piece or rod, typically of copper or similar conductive material, used as part of lightning security to guard tall or isolated structures from lightning damage. Its formal name is lightning finial. Sometimes, the system is informally referred to as:
A lightning conductor,
A lightning arrester, or
A lightning discharger.
However, these terms really refer to lightning guard systems in general or specific mechanism within them.
Lightning rod dissipaters make a structure less nice-looking by which charges can flow to the air around it. This then reduces the voltage between the point and the storm cloud, making a strike less likely. The most common charge dissipaters appear as slightly-blunted metal spikes sticking out in all information from a metal ball. These are mounted on short metal arms at the very top of a radio antenna or tower, the area by far most likely to be struck. These devices diminish, but do not eradicate, the risk of lightning strikes.
A lightning conductor,
A lightning arrester, or
A lightning discharger.
However, these terms really refer to lightning guard systems in general or specific mechanism within them.
Lightning rod dissipaters make a structure less nice-looking by which charges can flow to the air around it. This then reduces the voltage between the point and the storm cloud, making a strike less likely. The most common charge dissipaters appear as slightly-blunted metal spikes sticking out in all information from a metal ball. These are mounted on short metal arms at the very top of a radio antenna or tower, the area by far most likely to be struck. These devices diminish, but do not eradicate, the risk of lightning strikes.
Wednesday, May 16, 2007
History of Personal computer
An near the beginning use of the term appeared in a November 3, 1962, New York Times
article exposure John W. Mauchly's vision of expectations computing spoken to a conference of the American Institute of Industrial Engineers that previous day. Mauchly told the gathering, "There is no reason to suppose the average boy or girl cannot be master of a personal computer."
The initial computers that can be called 'personal' were the first Non -main frame computers, the LINC and the PDP-8. By today's standards they were big, expensive, and had small magnetic core memories.
However, they were small and cheap for individual laboratories and research projects to use, freeing them from the consignment dispensation and establishment of the typical industrial or university computing center. In addition, they were reasonably interactive and soon had their own operating systems. Finally, this category became known as the mini-computer, usually with time-sharing and program development facilities. Ultimately, the mini-computer grew up to encompass the VAX and larger mini-computers from Data General, Prime, and others.
Deployment of mini-computer systems was a replica for how personal computers would be used, but few of the mini-computer makers managed to profit from it.
article exposure John W. Mauchly's vision of expectations computing spoken to a conference of the American Institute of Industrial Engineers that previous day. Mauchly told the gathering, "There is no reason to suppose the average boy or girl cannot be master of a personal computer."
The initial computers that can be called 'personal' were the first Non -main frame computers, the LINC and the PDP-8. By today's standards they were big, expensive, and had small magnetic core memories.
However, they were small and cheap for individual laboratories and research projects to use, freeing them from the consignment dispensation and establishment of the typical industrial or university computing center. In addition, they were reasonably interactive and soon had their own operating systems. Finally, this category became known as the mini-computer, usually with time-sharing and program development facilities. Ultimately, the mini-computer grew up to encompass the VAX and larger mini-computers from Data General, Prime, and others.
Deployment of mini-computer systems was a replica for how personal computers would be used, but few of the mini-computer makers managed to profit from it.
Sunday, May 13, 2007
Cold River (Maine)
The Cold River is a 16.4 mile long (26.5 km) river situated in western Maine in the United States. It very briefly enters New Hampshire as well. It is part of the Saco River drainage basin.
The Cold River begins at the height of land in Evans Notch, a pass through the eastern White Mountains. Maine Highway 113, a narrow two-lane road, passes through the notch, following the Cold River on the south side and Evans Brook, a tributary of the Androscoggin River, on the north. The Cold River, flowing south, picks up the Mad River, a short stream with waterfalls that flows off the southern faces of East Royce and West Royce mountains, then reaches the southern base of Evans Notch at the junction of Basin Brook, coming out of a large glacial cirque to the west, where the Cold River national forest campground is situated.
South of Basin Brook, the Cold River briefly enters New Hampshire near the village of North Chatham, then veers back into Maine, flowing south-southwest in the town of Stow through an ever-widening valley. The Little Cold River enters from the west near the village of Stow. The Cold River ends at Charles Pond in the northern corner of Fryeburg. Water flows from Charles Pond via the short Charles River, entering the Old Course of the Saco River and finally the Saco itself south of Kezar Pond.
The Cold River begins at the height of land in Evans Notch, a pass through the eastern White Mountains. Maine Highway 113, a narrow two-lane road, passes through the notch, following the Cold River on the south side and Evans Brook, a tributary of the Androscoggin River, on the north. The Cold River, flowing south, picks up the Mad River, a short stream with waterfalls that flows off the southern faces of East Royce and West Royce mountains, then reaches the southern base of Evans Notch at the junction of Basin Brook, coming out of a large glacial cirque to the west, where the Cold River national forest campground is situated.
South of Basin Brook, the Cold River briefly enters New Hampshire near the village of North Chatham, then veers back into Maine, flowing south-southwest in the town of Stow through an ever-widening valley. The Little Cold River enters from the west near the village of Stow. The Cold River ends at Charles Pond in the northern corner of Fryeburg. Water flows from Charles Pond via the short Charles River, entering the Old Course of the Saco River and finally the Saco itself south of Kezar Pond.
Tuesday, May 08, 2007
Chocolate
Chocolate comprises a number of raw and processed foods that create from the seed of the tropical cacao tree. It is a common ingredient in many kinds of confections such as chocolate bars, candy, ice cream, cookies, cakes, pies, chocolate mousse, and other desserts. It is one of the most popular flavours in the world.
Chocolate was shaped by the Mesoamerican civilization, from cacao beans, and cultivated by pre-Columbian civilizations such as the Maya and Aztec, who used it as a basic part in a variety of sauces and beverages. The cocoa beans were ground and mixed with water to create a variety of beverages, both sweet and bitter, which were kept for only the highest noblemen and clerics of the Mesoamerican world. Chocolate is made from the fermented, roasted, and ground beans taken from the pod of the tropical cacao tree, Theobroma cacao, which was native to Central America and Mexico, but is now cultivated all through the tropics. The beans have an intensely flavoured bitter taste. The resultant products are known as "chocolate" or, in some parts of the world, cocoa.
Chocolate was shaped by the Mesoamerican civilization, from cacao beans, and cultivated by pre-Columbian civilizations such as the Maya and Aztec, who used it as a basic part in a variety of sauces and beverages. The cocoa beans were ground and mixed with water to create a variety of beverages, both sweet and bitter, which were kept for only the highest noblemen and clerics of the Mesoamerican world. Chocolate is made from the fermented, roasted, and ground beans taken from the pod of the tropical cacao tree, Theobroma cacao, which was native to Central America and Mexico, but is now cultivated all through the tropics. The beans have an intensely flavoured bitter taste. The resultant products are known as "chocolate" or, in some parts of the world, cocoa.
Friday, May 04, 2007
Peafowl
The peafowl are the three variety of bird in the genera Pavo and Afropavo of the pheasant family, Phasianidae. They are most distinguished for the male's profligate tail, a result of sexual selection, which it displays as part of courtship. The male is called a peacock, the female a peahen. In common English custom, however, "peacock" is used to mean any peafowl.
Overview
The characteristic Asiatic peafowl belonging to the genus Pavo comprise the familiar Indian Peafowl, Pavo cristatus and the poorly known Dragon birds or Green Peafowl Pavo muticus. Some biologists believe that there are at least five characteristic and critically endangered species of Green Peafowl while others classify them into a single species with three species.
The Arakan Dragonbird Pavo spicifer was once inhabitant to Northern Western Myanmar, Southern Tibet and Assam. The Indo-Chinese or Siamese Dragon bird Pavo imperator was once native to South East Myanmar and Thailand. The Annametic Dragonbird Pavo annamensis occupied the broadleaf evergreen forests of Cambodia, Vietnam, Laos and Southern Yunnan China.
The Javanese Green Peafowl, Pavo javanensis is occupant only to the island of Java. The died out Malay or Pahang Peafowl Pavo muticus muticus was fantasy by early naturalists to least the Pliocene rules out an foreword by humans. Northern Yunnan is the home of one of the most fascinating forms of Green Peafowl. The Yunnan Dragonbird, Pavo yunnanensis is most characteristic.
When it is not in show, the long tail rests on the ground and hampers the actions of the peacock
The White Peacock is frequently incorrect for an albino, but is a color change
Overview
The characteristic Asiatic peafowl belonging to the genus Pavo comprise the familiar Indian Peafowl, Pavo cristatus and the poorly known Dragon birds or Green Peafowl Pavo muticus. Some biologists believe that there are at least five characteristic and critically endangered species of Green Peafowl while others classify them into a single species with three species.
The Arakan Dragonbird Pavo spicifer was once inhabitant to Northern Western Myanmar, Southern Tibet and Assam. The Indo-Chinese or Siamese Dragon bird Pavo imperator was once native to South East Myanmar and Thailand. The Annametic Dragonbird Pavo annamensis occupied the broadleaf evergreen forests of Cambodia, Vietnam, Laos and Southern Yunnan China.
The Javanese Green Peafowl, Pavo javanensis is occupant only to the island of Java. The died out Malay or Pahang Peafowl Pavo muticus muticus was fantasy by early naturalists to least the Pliocene rules out an foreword by humans. Northern Yunnan is the home of one of the most fascinating forms of Green Peafowl. The Yunnan Dragonbird, Pavo yunnanensis is most characteristic.
When it is not in show, the long tail rests on the ground and hampers the actions of the peacock
The White Peacock is frequently incorrect for an albino, but is a color change
Monday, April 30, 2007
Door
A door is a makeup in a wall that allows easy transformation between an opening and a closed wall. It is establish in many houses and other buildings: internal ones, doors giving access to the street/external world, and doors to private outdoor areas such as a garden or balcony. In an apartment building, an midway kind is the outer door of an apartment, inside the building.
History
The first records are those represented in the paintings of the Egyptian tombs, in which they are shown as single or double doors, each in a single piece of wood. In Egypt, where the climate is intensely dry, there would be no fear of their warping, but in other countries it would be necessary to frame them, which according to Vitruvius was done with stiles and rails: the spaces enclosed being filled with panels let into grooves made in the stiles and rails. The stiles were the vertical boards, one of which, tenoned or hinged, is known as the hanging stile, the other as the middle or meeting stile. The horizontal cross pieces are the top rail, bottom rail, and middle or intermediate rails. The most ancient doors were in timber, those made for King Solomon's temple being in olive wood, which were fixed and overlaid with gold. The doors dwelt upon in Homer would appear to have been cased in silver or brass. Besides Olive wood, elm, cedar, oak and cypress were used.
All ancient doors were hung by pivots at the top and bottom of the hanging stile which worked in sockets in the lintel and cill, the final being always in some hard stone such as basalt or granite. Those found at Nippur by Dr. Hilprecht, dating from 2000 B.C. were in dolorite. The tenons of the gates at Balawat were covered with bronze. These doors or gates were hung in two leaves, each about 8 ft.4 in. wide and 27 ft. high; they were enclosed with bronze bands or strips, 10 in. high, covered with repouss embellishment of figures, etc. The wood doors would seem to have been about 3 in. thick, but the hanging stile was over 14 inches diameter. Other sheathings of various sizes in bust have been found, which proves this to have been the universal method adopted to protect the wood pivots. In the Hauran in Syria, where timber is scarce the doors were made in stone, and one measuring 5 ft. 4 in. by 2 ft. 7 in. is in the British Museum; the band on the meeting stile shows that it was one of the leaves of a double door. At Kuffeir near Bostra in Syria, Burckhardt found stone doors, 9 to 10 ft. high, being the entrance doors of the town. In Etruria many stone doors are referred to by Dennis.
History
The first records are those represented in the paintings of the Egyptian tombs, in which they are shown as single or double doors, each in a single piece of wood. In Egypt, where the climate is intensely dry, there would be no fear of their warping, but in other countries it would be necessary to frame them, which according to Vitruvius was done with stiles and rails: the spaces enclosed being filled with panels let into grooves made in the stiles and rails. The stiles were the vertical boards, one of which, tenoned or hinged, is known as the hanging stile, the other as the middle or meeting stile. The horizontal cross pieces are the top rail, bottom rail, and middle or intermediate rails. The most ancient doors were in timber, those made for King Solomon's temple being in olive wood, which were fixed and overlaid with gold. The doors dwelt upon in Homer would appear to have been cased in silver or brass. Besides Olive wood, elm, cedar, oak and cypress were used.
All ancient doors were hung by pivots at the top and bottom of the hanging stile which worked in sockets in the lintel and cill, the final being always in some hard stone such as basalt or granite. Those found at Nippur by Dr. Hilprecht, dating from 2000 B.C. were in dolorite. The tenons of the gates at Balawat were covered with bronze. These doors or gates were hung in two leaves, each about 8 ft.4 in. wide and 27 ft. high; they were enclosed with bronze bands or strips, 10 in. high, covered with repouss embellishment of figures, etc. The wood doors would seem to have been about 3 in. thick, but the hanging stile was over 14 inches diameter. Other sheathings of various sizes in bust have been found, which proves this to have been the universal method adopted to protect the wood pivots. In the Hauran in Syria, where timber is scarce the doors were made in stone, and one measuring 5 ft. 4 in. by 2 ft. 7 in. is in the British Museum; the band on the meeting stile shows that it was one of the leaves of a double door. At Kuffeir near Bostra in Syria, Burckhardt found stone doors, 9 to 10 ft. high, being the entrance doors of the town. In Etruria many stone doors are referred to by Dennis.
Tuesday, April 24, 2007
Northern Mockingbird
The Northern Mockingbird, Mimus polyglottos, is the mockingbird commonly originate in North America.Adults are grey on the head and upperparts with pale yellow eyes and a slim black bill with a slight downward curve; the underparts are light. They have a long dark tail by means of white edges and long dark legs. They have white wing bars and show white wing patches in flight.Their breeding habitat is areas with a mix of open areas and dense shrubs from southern Canada to Mexico, but is most common in the southern United States. They build a twig nest in a dense shrub or tree. This bird forcefully defends its nest against other birds and animals, including humans. When a predator is persistent mockingbirds from adjacent territories, summoned by a distinct call, may join the attack. Other birds may gather to watch as the mockingbirds harass the intruder.
They are usually permanent residents; northern birds may move south during harsh weather. However, this species has occurred in Europe as an extreme rarity.These birds forage on the ground or in vegetation; they also fly down from a perch to capture food. They mainly eat insects and berries. While foraging they will regularly spread their wings in a peculiar two-step motion to display the white patches underneath. The purpose of this behavior is disputed. Some ornithologists claim this is merely a territorial display, while others say that flashing the white patches startles hiding insects and forces them into the open. Both theories seem to have some merit.
This bird imitates the calls of other birds, animal sounds and yet machine noises. It is often found in urban areas. They often call through the night and may continue year-round apart from for the summer moulting season. Mockingbirds usually sing the loudest in the twilight of the early morning when the sun is on the horizon. While singing on a high perch they will often bolt more than a few feet into the air in a looping motion, with wings outstretched to display their white underside, then land back on the perch without breaking a note. That serves as a territorial display.Mockingbirds have a strong preference for certain trees, such as maple, sweet gum (green 5-pointed leaves and prickly porous balls), and sycamore. They normally avoid pine trees. In urban areas, mockingbirds rarely come down to the ground, unlike most birds. Also, they have a particular preference for high places, such as the topmost branches of trees and the tops of telephone poles.
They are usually permanent residents; northern birds may move south during harsh weather. However, this species has occurred in Europe as an extreme rarity.These birds forage on the ground or in vegetation; they also fly down from a perch to capture food. They mainly eat insects and berries. While foraging they will regularly spread their wings in a peculiar two-step motion to display the white patches underneath. The purpose of this behavior is disputed. Some ornithologists claim this is merely a territorial display, while others say that flashing the white patches startles hiding insects and forces them into the open. Both theories seem to have some merit.
This bird imitates the calls of other birds, animal sounds and yet machine noises. It is often found in urban areas. They often call through the night and may continue year-round apart from for the summer moulting season. Mockingbirds usually sing the loudest in the twilight of the early morning when the sun is on the horizon. While singing on a high perch they will often bolt more than a few feet into the air in a looping motion, with wings outstretched to display their white underside, then land back on the perch without breaking a note. That serves as a territorial display.Mockingbirds have a strong preference for certain trees, such as maple, sweet gum (green 5-pointed leaves and prickly porous balls), and sycamore. They normally avoid pine trees. In urban areas, mockingbirds rarely come down to the ground, unlike most birds. Also, they have a particular preference for high places, such as the topmost branches of trees and the tops of telephone poles.
Wednesday, April 18, 2007
Radio clock
A radio clock is a clock that is synchronized by a time code bit stream transmitted by a radio transmitter associated to a time standard such as an atomic clock. The picture shows a type of radio controlled digital clock. With special mechanism, radio controlled analog clocks are also available.
A radio controlled clock consists of an antenna for intercepting the RF time code signal, a receiving circuit to exchange the time code RF signal into digital time code, and a controller circuit to decode the time code bit streams and to drive an output circuit which can be LCD in case of digital clocks or stepping motors in case of analog clocks.
A radio controlled clock consists of an antenna for intercepting the RF time code signal, a receiving circuit to exchange the time code RF signal into digital time code, and a controller circuit to decode the time code bit streams and to drive an output circuit which can be LCD in case of digital clocks or stepping motors in case of analog clocks.
Tuesday, April 10, 2007
Satellite phone
A satellite telephone, satellite phone, or satphone is a mobile phone that communicates directly with orbiting communications satellites. Depending on the architecture of a particular system, coverage may comprise the entire Earth, or only specific regions.
Satellite phone (Inmarsat)The mobile equipment, also known as a terminal or earth station, varies generally. A satellite phone handset has a size and weight comparable to that of a late 1980s or early 1990s cell phone, but with a large retractable antenna. These are popular on expeditions into remote areas where terrestrial cellular service is unavailable.
A fixed installation, such as used shipboard, may include large, rugged, rack-mounted electronics, and a steerable microwave antenna on the mast that mechanically tracks the overhead satellites.
Satellite phone (Inmarsat)The mobile equipment, also known as a terminal or earth station, varies generally. A satellite phone handset has a size and weight comparable to that of a late 1980s or early 1990s cell phone, but with a large retractable antenna. These are popular on expeditions into remote areas where terrestrial cellular service is unavailable.
A fixed installation, such as used shipboard, may include large, rugged, rack-mounted electronics, and a steerable microwave antenna on the mast that mechanically tracks the overhead satellites.
Friday, April 06, 2007
Smartphone
A smartphone is any electronic handheld device that integrates the functionality of a mobile phone, personal digital assistant or other information appliance. This is frequently achieved by adding telephone functions to an existing PDA or putting "smart" capabilities, such as PDA functions, into a mobile phone. A key characteristic of a smartphone is that additional applications can be installed on the device. The applications can be developed by the manufacturer of the handheld device, by the operator or by any other third-party software developer.
It is increasingly difficult to define exactly what qualifies as a smartphone. Almost all new mobile phones have some rudimentary PDA functionality such as phonebooks, calendars, and task lists. Furthermore, BREW and Java ME devices allow for the installation of additional applications but are still not considered smartphones. There are many BREW devices with PDA functionality, the ability to run third-party applications in native code and sporting displays as large as 240x320 pixels; yet they are not considered smartphones. The elusive definition seems loosely tied to the particular operating systems listed below.
It is increasingly difficult to define exactly what qualifies as a smartphone. Almost all new mobile phones have some rudimentary PDA functionality such as phonebooks, calendars, and task lists. Furthermore, BREW and Java ME devices allow for the installation of additional applications but are still not considered smartphones. There are many BREW devices with PDA functionality, the ability to run third-party applications in native code and sporting displays as large as 240x320 pixels; yet they are not considered smartphones. The elusive definition seems loosely tied to the particular operating systems listed below.
Monday, April 02, 2007
Sun
The Sun is the star at the centre of our Solar system. It is infrequently referred to as Sol to distinguish it from other "suns". Planet Earth orbits the Sun, as do many other bodies, with other planets, asteroids, meteoroids, comets and dust. Its heat and light support almost all life on Earth.
The Sun has a mass of about 2×1030kg, which is fairly higher than that of an average star. About 74% of its mass is hydrogen, with 25% helium and the rest made up of trace quantities of heavier elements. It is consideration that the Sun is about 5 billion years old, and is about half way through its main sequence evolution, throughout which nuclear fusion reactions in its core fuse hydrogen into helium. In about 5 billion years time the Sun will become a planetary nebula.
Although it is the nearest star to Earth and has been intensively studied by scientists, many questions about the Sun remain unanswered, such as why its outer atmosphere has a temperature of over 106 K when its visible surface has a temperature of just 6,000 K.
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The Sun has a mass of about 2×1030kg, which is fairly higher than that of an average star. About 74% of its mass is hydrogen, with 25% helium and the rest made up of trace quantities of heavier elements. It is consideration that the Sun is about 5 billion years old, and is about half way through its main sequence evolution, throughout which nuclear fusion reactions in its core fuse hydrogen into helium. In about 5 billion years time the Sun will become a planetary nebula.
Although it is the nearest star to Earth and has been intensively studied by scientists, many questions about the Sun remain unanswered, such as why its outer atmosphere has a temperature of over 106 K when its visible surface has a temperature of just 6,000 K.
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Thursday, March 29, 2007
Lens
A lens is a device for either concentrating or diverging light, normally formed from a piece of shaped glass. Analogous devices used with other types of electromagnetic radiation are also called lenses: for instance, a microwave lens can be made from paraffin wax.
The earliest records of lenses date to Ancient Greece, with Aristophanes' play The Clouds (424 BC) mentioning a burning-glass (a convex lens used to focus the sun's rays to produce fire). The writings of Pliny the Elder also show that burning-glasses were recognized to the Roman Empire, and mentions what is possibly the first use of a corrective lens: Nero was known to watch the gladiatorial games throughout a concave-shaped emerald (presumably to correct for myopia). Seneca the Younger (3 BC--65) described the magnifying effect of a glass globe filled with water.Widespread use of lenses did not happen until the invention of spectacles, probably in Italy in the 1280s.
The earliest records of lenses date to Ancient Greece, with Aristophanes' play The Clouds (424 BC) mentioning a burning-glass (a convex lens used to focus the sun's rays to produce fire). The writings of Pliny the Elder also show that burning-glasses were recognized to the Roman Empire, and mentions what is possibly the first use of a corrective lens: Nero was known to watch the gladiatorial games throughout a concave-shaped emerald (presumably to correct for myopia). Seneca the Younger (3 BC--65) described the magnifying effect of a glass globe filled with water.Widespread use of lenses did not happen until the invention of spectacles, probably in Italy in the 1280s.
Monday, March 26, 2007
Computer
A computer is a device capable of processing data according to a program — a list of instructions. The data to be processed may represent many types of information including numbers, text, pictures, or sound.
Computers can be enormously versatile. In fact, they are universal information processing machines. According to the Church-Turing thesis, a computer with a certain minimum threshold capability is in principle capable of performing the tasks of any other computer, from those of a personal digital assistant to a supercomputer. Therefore, the same computer designs have been adapted for tasks from processing company payrolls to controlling industrial robots. Modern electronic computers also have enormous speed and ability for information processing compared to earlier designs, and they have become exponentially more powerful over the years (a phenomenon known as Moore's Law).
Computers are available in many physical forms. The original computers were the size of a large room, and such enormous computing services still exist for specialized scientific computation - supercomputers - and for the transaction processing requirements of large companies, usually called mainframes. Smaller computers for individual use, called personal computers, and their portable equivalent, the notebook computer, are ubiquitous information-processing and communication tools and be perhaps what most non-experts think of as "a computer". However, the most common form of computer in use today is the embedded computer, small computers used to control another device. Embedded computers control machines from fighter planes to digital cameras.
Computers can be enormously versatile. In fact, they are universal information processing machines. According to the Church-Turing thesis, a computer with a certain minimum threshold capability is in principle capable of performing the tasks of any other computer, from those of a personal digital assistant to a supercomputer. Therefore, the same computer designs have been adapted for tasks from processing company payrolls to controlling industrial robots. Modern electronic computers also have enormous speed and ability for information processing compared to earlier designs, and they have become exponentially more powerful over the years (a phenomenon known as Moore's Law).
Computers are available in many physical forms. The original computers were the size of a large room, and such enormous computing services still exist for specialized scientific computation - supercomputers - and for the transaction processing requirements of large companies, usually called mainframes. Smaller computers for individual use, called personal computers, and their portable equivalent, the notebook computer, are ubiquitous information-processing and communication tools and be perhaps what most non-experts think of as "a computer". However, the most common form of computer in use today is the embedded computer, small computers used to control another device. Embedded computers control machines from fighter planes to digital cameras.
Wednesday, March 21, 2007
Motorcycle
A motorcycle (or motorbike) is a two-wheeled vehicle powered by an engine. The wheels are in-line, and at higher speed the motorcycle remains upright and stable by virtue of gyroscopic forces; at lower speeds repeated readjustment of the steering by the rider gives constancy. The rider sits astride the vehicle on a seat, with hands on a set of handlebars which are used to steer the motorcycle, in conjunction with the rider shifting his weight through his feet, which are supported on a set of "footpegs" or "pegs" which stick out from the frame
Friday, March 16, 2007
Pied-billed Grebe
The Pied-billed Grebe, Podilymbus podiceps, †) is a associate of the grebe family of water birds. Since the Atitlan Grebe, Podilymbus gigas, has become wiped out, it is the sole extant member of the genus Podilymbus.
The Pied-billed Grebe breeds across Canada, parts of the United States and temperate South America. though this species does not appear to be a strong flier, it has occurred in Europe as a rare vagrant on a number of occasions, and one bird in England bred by means of a Little Grebe, producing hybrid young.
The most widespread of North American grebes, it is found on remote ponds, marshes, and sluggish streams. It is frequently the first grebe to arrive on northern inland waters in springtime, and the last to leave in autumn. It is rare on salt water. This grebe rarely flies, preferring to escape danger by diving.
It feeds on fish (carp, catfish, eels), insects (dragonflies, ants, beetles), and amphibians (frogs, tadpoles).
The Pied-billed Grebe is small at 31-38 cm (12"-15") in length, stocky, and short-necked. It has a short, blunt chicken-like bill, which in summer is encircled by a broad black band (hence the name). It is the only grebe that does not show a white wing patch in flight.
This grebe is typically silent, except in breeding season when the male voices a loud, laughing cuck, cuck, cuck or cow, cow, cow.
Folk names of this grebe include dabchick, devil-diver, dive-dapper, hell-diver, and water witch
The Pied-billed Grebe breeds across Canada, parts of the United States and temperate South America. though this species does not appear to be a strong flier, it has occurred in Europe as a rare vagrant on a number of occasions, and one bird in England bred by means of a Little Grebe, producing hybrid young.
The most widespread of North American grebes, it is found on remote ponds, marshes, and sluggish streams. It is frequently the first grebe to arrive on northern inland waters in springtime, and the last to leave in autumn. It is rare on salt water. This grebe rarely flies, preferring to escape danger by diving.
It feeds on fish (carp, catfish, eels), insects (dragonflies, ants, beetles), and amphibians (frogs, tadpoles).
The Pied-billed Grebe is small at 31-38 cm (12"-15") in length, stocky, and short-necked. It has a short, blunt chicken-like bill, which in summer is encircled by a broad black band (hence the name). It is the only grebe that does not show a white wing patch in flight.
This grebe is typically silent, except in breeding season when the male voices a loud, laughing cuck, cuck, cuck or cow, cow, cow.
Folk names of this grebe include dabchick, devil-diver, dive-dapper, hell-diver, and water witch
Sunday, March 11, 2007
Snow cave
A snow cave is a shelter made in snow by mountain climbers and other outdoor winter recreational enthusiasts. The shelter has properties associated to an Igloo and is mainly effective at providing protection from wind as well as low temperatures. A properly made snow cave can be 0 °C (32 °F) or warmer inside, even when outside temperatures are -40 °C (-40 °F).[1] [2]
A snow cave is built by excavating snow in such a way that the entrance tunnel enters from under the main space to retain warm air. Construction is simplified by building it on a steep slope and digging slightly upwards and horizontally into the slope. The roof is domed to prevent dripping on the occupants. sufficient snow depth, free of rocks and ice, is needed. Generally at 4 or 5 feet is enough. The snow must be consolidated, so it retains its structure. The walls and roof be supposed to be at least 12 inches thick.
A narrow entrance tunnel, a little wider than a human leads into the main chamber which consists of a flat area, perhaps with elevated sleeping platform(s), also excavated from snow. Most sources agree that using tools such as a shovel and ice axe are vital; digging by hand is for emergencies only.
A snow cave is built by excavating snow in such a way that the entrance tunnel enters from under the main space to retain warm air. Construction is simplified by building it on a steep slope and digging slightly upwards and horizontally into the slope. The roof is domed to prevent dripping on the occupants. sufficient snow depth, free of rocks and ice, is needed. Generally at 4 or 5 feet is enough. The snow must be consolidated, so it retains its structure. The walls and roof be supposed to be at least 12 inches thick.
A narrow entrance tunnel, a little wider than a human leads into the main chamber which consists of a flat area, perhaps with elevated sleeping platform(s), also excavated from snow. Most sources agree that using tools such as a shovel and ice axe are vital; digging by hand is for emergencies only.
Tuesday, March 06, 2007
Fog bow
A fog bow is comparable to a rainbow, but because of the very small size of water droplets that cause fog, smaller than 0.05 mm, the fog bow has no colors and appears white. Fogbows are sometimes called "white rainbows" or "cloudbows". Mariners sometimes call them "sea-dogs".
The fogbow's relative lack of colors are caused by the relatively smaller water drops... so small that the quantum mechanical wavelength of light becomes significant and smears out colors that would be created by larger rainbow water drops.
This is significantly different from a moonbow, where the colours exist but are regularly not seen because the moonbow is so faint.
The fogbow's relative lack of colors are caused by the relatively smaller water drops... so small that the quantum mechanical wavelength of light becomes significant and smears out colors that would be created by larger rainbow water drops.
This is significantly different from a moonbow, where the colours exist but are regularly not seen because the moonbow is so faint.
Thursday, March 01, 2007
Internet vs. Web
The Internet and the World Wide Web are not synonymous: the Internet is a collection of interconnected computer networks, linked by copper wires, fiber-optic cables, wireless connections, etc.; the Web is a collected works of interconnected documents and other resources, linked by hyperlinks and URLs. The World Wide Web is available via the Internet, as are many other services with e-mail, file sharing, and others described below.
The best way to define and differentiate between these terms is with reference to the Internet protocol suite. This collection of standards and protocols is ordered into layers such that each layer provides the foundation and the services necessary by the layer above. In this conception, the term Internet refers to computers and networks that communicate using IP (Internet protocol) and TCP (transfer control protocol). Once this networking structure is recognized, then other protocols can run “on top.” These other protocols are sometimes called services or applications. Hypertext transfer protocol, or HTTP, is the application layer protocol that relations and provides access to the files, documents and other resources of the World Wide Web.
The best way to define and differentiate between these terms is with reference to the Internet protocol suite. This collection of standards and protocols is ordered into layers such that each layer provides the foundation and the services necessary by the layer above. In this conception, the term Internet refers to computers and networks that communicate using IP (Internet protocol) and TCP (transfer control protocol). Once this networking structure is recognized, then other protocols can run “on top.” These other protocols are sometimes called services or applications. Hypertext transfer protocol, or HTTP, is the application layer protocol that relations and provides access to the files, documents and other resources of the World Wide Web.
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