The key benefit of RAM over types of storage which need physical movement is that retrieval times are short and consistent. Short because no physical movement is required, and consistent because the time taken to retrieve a piece of data does not depend on its current distance from a physical head; it requires practically the equal amount of time to access any piece of data stored in a RAM chip.
Because of this speed and consistency, RAM is used as 'main memory' or primary storage: the working area used for loading, displaying and manipulate applications and data. In most personal computers, the RAM is not an essential part of the motherboard or CPU—it comes in the easily upgraded form of modules called memory sticks or RAM sticks about the size of a few sticks of chewing gum, which can be quickly detached and replaced when they become damaged or too small for current purposes. A smaller amount of random-access memory is also integrated with the CPU, but this is usually referred to as "cache" memory, rather than RAM.
The disadvantage of RAM over physically moving media is cost and the loss of data when power is turned off. For these reasons, almost all PCs have disc storage as "secondary storage". Small PDAs and music players (up to 8 GiB in Jan 2007) may allot with disks, but rely on flash memory, to retain data between sessions of use.
Sunday, May 27, 2007
Friday, May 18, 2007
Moore machine
Moore model control of a winch door in the theory of computation, a Moore machine is a finite state automaton where the outputs are determined by the current state alone. The state diagram for a Moore machine will include an output signal for each state. Compare with a Mealy machine, which maps transitions in the machine to outputs.
The name Moore machine comes from that of its supporter, Edward F. Moore, a state-machine pioneer who wrote "Gedanken-experiments on Sequential Machines".
Most digital electronic systems are designed as clocked sequential systems. Clocked sequential systems are a limited form of Moore machine where the state changes only when the global clock signal changes. Typically the current state is stored in flip-flops, and a global clock signal is connected to the "clock" input of the flip-flops. Clocked chronological systems are one way to solve met stability problems.
A typical electronic Moore machine includes a combinatorial logic chain to decode the current state into the outputs. The instant the current state changes, those changes ripple through that chain, and almost instantaneously the outputs change. There are design techniques to ensure that no glitches occur on the outputs during that brief period while those changes are rippling through the chain, but most systems are designed so that glitches during that brief transition time are ignored or are irrelevant. The outputs then stay the same indefinitely, until the Moore machine changes state again.
The name Moore machine comes from that of its supporter, Edward F. Moore, a state-machine pioneer who wrote "Gedanken-experiments on Sequential Machines".
Most digital electronic systems are designed as clocked sequential systems. Clocked sequential systems are a limited form of Moore machine where the state changes only when the global clock signal changes. Typically the current state is stored in flip-flops, and a global clock signal is connected to the "clock" input of the flip-flops. Clocked chronological systems are one way to solve met stability problems.
A typical electronic Moore machine includes a combinatorial logic chain to decode the current state into the outputs. The instant the current state changes, those changes ripple through that chain, and almost instantaneously the outputs change. There are design techniques to ensure that no glitches occur on the outputs during that brief period while those changes are rippling through the chain, but most systems are designed so that glitches during that brief transition time are ignored or are irrelevant. The outputs then stay the same indefinitely, until the Moore machine changes state again.
Sunday, May 13, 2007
Sunglass
Sunglasses are a kind of visual correction aid, variously termed spectacles or glasses, which feature lenses that are colored or darkened to screen out strong light from the eyes.
Many people find direct sunlight too bright to be comfortable, particularly when reading from paper on which the sun directly shines. In outdoor activities like skiing and flying, the eye can receive more light than usual. It has been recommended to wear these kinds of glasses on sunny days to protect the eyes from ultraviolet radiation, which can lead to the development of a cataract. Sunglasses have also been linked with celebrities and film actors mainly due to the desire to mask identity, but in part due to the lighting involved in production being typically stronger than natural light and uncomfortable to the naked eye.
Many people find direct sunlight too bright to be comfortable, particularly when reading from paper on which the sun directly shines. In outdoor activities like skiing and flying, the eye can receive more light than usual. It has been recommended to wear these kinds of glasses on sunny days to protect the eyes from ultraviolet radiation, which can lead to the development of a cataract. Sunglasses have also been linked with celebrities and film actors mainly due to the desire to mask identity, but in part due to the lighting involved in production being typically stronger than natural light and uncomfortable to the naked eye.
Wednesday, May 09, 2007
Vehicle
Vehicles are non-living means of moving. They are most often man-made, although some other means of moving which are not made by man can also be called vehicles; examples include icebergs and floating 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 means of transportation, are not called vehicles. This includes humans carrying another human, for example a child or a disabled person. Vehicles that do not travel on land are often called crafts, such as watercraft, sail craft, aircraft, hovercraft and spacecraft most land vehicles have wheels. Please see the wheel article for examples of vehicles with and without wheels. Movement without the help of a vehicle or an animal is called locomotion. The word vehicle itself comes from the Latin vehicular.
Tuesday, May 01, 2007
History of Postage Stamp
The world's initial stamp was the Penny Black the adhesive postage stamp and the uniform postage rate were devised in Great Britain by James Chalmers around 1834. The same ideas were brought forward by Lovrenc Kosir, a Slovenian postal clerk at the Viennese court in 1835, but did not meet a positive reply. Later, the concept of the adhesive postage stamp was published by Rowland Hill, in Postal Reform: its Importance and Tractability in 1837. In it he argued that it would be better for the sender to pay the cost of release, rather than the addressee who could refuse the letter if they could not or did not want to pay, as sometimes happened at the time. He also argued for a uniform rate of one penny per letter, no matter where its destination. Accounting costs for the government would thus be cut; postage would no longer be charged according to how far a letter had traveled, which required each letter to have an individual entry in the Royal Mail's accounts. Chalmers' ideas were lastly adopted by Parliament in August, 1839 and the General Post Office launched the Penny Post service the next year in 1840 with two prepaid-postage pictorial envelopes or wrappers: one valued at a penny and one valued at two pence.
Three months shortly the first prepaid-postage stamp, known as the Penny Black was issued with the profile of Queen Victoria printed on it. Because the United Kingdom issued the first stamps, the Universal Postal Union grants it an exception from its rule that the recognition of the issuing country must appear on a stamp in Roman script for use in international mails. Previous to joining the U.P.U. many countries did not do this; there are very few violations of the rule since this time, though one example is the U.S. Pilgrim Tercentenary series, on which the country designation was involuntarily excluded. Because of this the numerous early issues of China and Japan often confound new collectors unfamiliar with Oriental scripts. A stamp must also show a face value in the issuing country's currency. Some countries have issued stamp with a letter of the alphabet or designation such as "First class" for a face value. Because of the U.P.U. rules their use is constrained to domestic mail, but breach of this rule is often tolerated. Exceptions to this are the British "E" stamp and the South African "International Letter Rate" stamp.
Friday, April 27, 2007
Tourism
Tourism is travel for predominantly leisure or relaxation purposes, and also refers to the prerequisite of services in support of this act. Tourists are people who ,travel to and stay in places outside their common environment for not more than one consecutive year for leisure, business and other purposes not related to work out of an activity remunerated from within the place visited.
Tourism has become an enormously popular, global activity. As a service industry, tourism has frequent tangible and intangible elements. Major tangible elements include transportation, accommodation, and other apparatus of a hospitality industry. Major intangible elements relate to the purpose or inspiration for becoming a tourist, such as rest, relaxation, the opportunity to meet new people and experience other cultures, or simply to do something different and have an adventure.
Tourism is crucial for many countries, due to the income generated by the expenditure of goods and services by tourists, the taxes levied on businesses in the tourism industry, and the prospect for employment and economic advancement by working in the industry.
Tourism has become an enormously popular, global activity. As a service industry, tourism has frequent tangible and intangible elements. Major tangible elements include transportation, accommodation, and other apparatus of a hospitality industry. Major intangible elements relate to the purpose or inspiration for becoming a tourist, such as rest, relaxation, the opportunity to meet new people and experience other cultures, or simply to do something different and have an adventure.
Tourism is crucial for many countries, due to the income generated by the expenditure of goods and services by tourists, the taxes levied on businesses in the tourism industry, and the prospect for employment and economic advancement by working in the industry.
Tuesday, April 24, 2007
Artificial intelligence (Collective and non-human intelligence)
Some thinkers have explored the idea of combined intelligence, arising from the harmonization of many people. A battleship, for instance, cannot be operated by a single person's knowledge, actions and intelligence; it takes a equivalent and interacting crew. Similarly, the interesting behaviors of a bee colony are not exhibited in the aptitude and actions of any single bee, but rather manifest in the performance of the hive. These ideas are explored as a basis for human thought, with applications for artificial intelligence, by MIT AI pioneers Norbert Wiener and Marvin Musky. Artificial intelligence has emerged from Computer science as a area of expertise which seeks to make computers act in gradually more intelligent ways, and provides insights into human thought processes.
When bearing in mind animal intelligence, a more general definition of intelligence might be applied: the "ability to adapt efficiently to the environment, either by making a change in oneself or by changing the surroundings or finding a new one". Many people have also speculated about the possibility of outer space intelligence.
When bearing in mind animal intelligence, a more general definition of intelligence might be applied: the "ability to adapt efficiently to the environment, either by making a change in oneself or by changing the surroundings or finding a new one". Many people have also speculated about the possibility of outer space intelligence.
Wednesday, April 18, 2007
Multitrack recording
Multitrack recording is a method of sound recording that allows for the recording of multiple sound sources, whether at the same time or at different times. This is probably the most common technique of recording popular music: Musicians or singers can be recorded independently, then these performances can be edited together to create a cohesive result. It is also called 'multitracking' or just 'tracking' for short.Multitrack recording devices are available with varying capacities. When recording a segment of audio, which is also known as a track, audio engineers and musicians may select which track or tracks on the device will be used.
Monday, April 09, 2007
Traffic calming
Traffic reassuring is a set of strategies used by urban planners and traffic engineers which aims to slow down traffic and improve safety for pedestrians and bicyclists, although some of these features can also be dangerous to cyclists. It is now relatively common in Europe, especially Northern Europe; less so in North America.
Traffic calming has traditionally been justified on the grounds of pedestrian security and reduction of noise and local air pollution which are side effects of the traffic. However, it has become increasingly apparent that streets have many social and recreational functions which are severely impaired by fast car traffic. For example, residents of streets with light traffic had, on average, three more friends and twice as many acquaintances as the people on streets with heavy traffic which were otherwise similar in dimensions, income, etc. For much of the twentieth century, streets were designed by engineers who were charged only with ensuring traffic flow and not with fostering the other functions of streets. The rationale for traffic calming is now broadening to include designing for these functions.
Displaced traffic is not fully pushed onto other routes, as some travelers may begin to walk or use other modes such as public transit and bicycles to get where they are going. Still, in most cases the affected motorists have few alternatives aside from either navigating the newly erected obstacles or finding a more palatable route. This happens because high traffic tends to be generated by motorists passing through the area and not by the local residents.
It should be noted the some of these measures have a tendency to irritate and annoy drivers rather than calm them and others can actually increase traffic throughput. Some drivers who slow down at calming points, however, accelerate and speed after passing them in order to "catch up for lost time". For this reason, more advanced methods integrated into the design of the street, which make slower speeds seem more natural to drivers and less of an artificial imposition, are now preferred - the goal is to slow down the driver through psychological, at least partly subconscious means instead of simply forcing him to do so.
One major side effect of traffic reassuring is the impedance to emergency services. A police car can easily navigate most traffic reassuring measures. The same cannot be said for fire trucks and ambulances, however. They often have to slow down to safely cross speed bumps or chicanes. In some locales, the law prohibits traffic calming measures along the routes used by the urgent situation services.
There are 3 "E"'s that traffic engineers refer to when discussing traffic reassuring: engineering, education, and enforcement. Because neighborhood traffic management studies have shown that often it is the residents themselves that are largely contributing to the perceived speeding problem within the neighborhood, it is strained that the most effective traffic calming plans will entail all three components, and that engineering measures alone will not produce satisfactory results.
Traffic calming has traditionally been justified on the grounds of pedestrian security and reduction of noise and local air pollution which are side effects of the traffic. However, it has become increasingly apparent that streets have many social and recreational functions which are severely impaired by fast car traffic. For example, residents of streets with light traffic had, on average, three more friends and twice as many acquaintances as the people on streets with heavy traffic which were otherwise similar in dimensions, income, etc. For much of the twentieth century, streets were designed by engineers who were charged only with ensuring traffic flow and not with fostering the other functions of streets. The rationale for traffic calming is now broadening to include designing for these functions.
Displaced traffic is not fully pushed onto other routes, as some travelers may begin to walk or use other modes such as public transit and bicycles to get where they are going. Still, in most cases the affected motorists have few alternatives aside from either navigating the newly erected obstacles or finding a more palatable route. This happens because high traffic tends to be generated by motorists passing through the area and not by the local residents.
It should be noted the some of these measures have a tendency to irritate and annoy drivers rather than calm them and others can actually increase traffic throughput. Some drivers who slow down at calming points, however, accelerate and speed after passing them in order to "catch up for lost time". For this reason, more advanced methods integrated into the design of the street, which make slower speeds seem more natural to drivers and less of an artificial imposition, are now preferred - the goal is to slow down the driver through psychological, at least partly subconscious means instead of simply forcing him to do so.
One major side effect of traffic reassuring is the impedance to emergency services. A police car can easily navigate most traffic reassuring measures. The same cannot be said for fire trucks and ambulances, however. They often have to slow down to safely cross speed bumps or chicanes. In some locales, the law prohibits traffic calming measures along the routes used by the urgent situation services.
There are 3 "E"'s that traffic engineers refer to when discussing traffic reassuring: engineering, education, and enforcement. Because neighborhood traffic management studies have shown that often it is the residents themselves that are largely contributing to the perceived speeding problem within the neighborhood, it is strained that the most effective traffic calming plans will entail all three components, and that engineering measures alone will not produce satisfactory results.
Monday, April 02, 2007
Goshawk
The Goshawk is a average large bird of prey in the family Accipitridae which also includes many other diurnal raptors such as eagles, buzzards and harriers.
It is a extensive species throughout the moderate parts of the northern hemisphere. In North America it is named as the Northern Goshawk. It is mostly resident, but birds from colder regions of north Asia and Canada wander south for the winter.
Goshawk in flight this kind nests in trees, building a new nest each year. It hunts birds and mammals in woodland, relying on surprise as it flies from a perch or hedge-hops to cruel circle its prey unaware. Animals as large as hares and Pheasant are taken. Its call is a ferocious shriek. Many older goshawks refuse to attack hares, if it was previously acutely kicked by a hare which it tried to catch.
In Eurasia, the male is confusable with a female Sparrow hawk, but is larger, much bulkier and has comparatively longer wings. In spring, he has a stunning roller-coaster display, and this is the best time to see this enigmatic forest bird.
It is a extensive species throughout the moderate parts of the northern hemisphere. In North America it is named as the Northern Goshawk. It is mostly resident, but birds from colder regions of north Asia and Canada wander south for the winter.
Goshawk in flight this kind nests in trees, building a new nest each year. It hunts birds and mammals in woodland, relying on surprise as it flies from a perch or hedge-hops to cruel circle its prey unaware. Animals as large as hares and Pheasant are taken. Its call is a ferocious shriek. Many older goshawks refuse to attack hares, if it was previously acutely kicked by a hare which it tried to catch.
In Eurasia, the male is confusable with a female Sparrow hawk, but is larger, much bulkier and has comparatively longer wings. In spring, he has a stunning roller-coaster display, and this is the best time to see this enigmatic forest bird.
Thursday, March 29, 2007
Major ice ages
There have been at least four main ice ages in the Earth's past.
The earliest hypothesized ice age is believed to have occurred around 2.7 to 2.3 billion years ago through the early Proterozoic Age.
Main article: Snowball Earth.
The most primitive well-documented ice age, and probably the most harsh of the last 1 billion years, occurred from 800 to 600 million years ago and it has been suggested that it formed a Snowball Earth in which permanent sea ice extensive to or very near the equator. It has been not compulsory that the end of this ice age was responsible for the subsequent Cambrian Explosion, though this theory is current and contentious.
The timing of ice ages all through geologic history is in part prohibited by the position of the continental plates on the surface of the Earth. When landmasses are determined near the Polar Regions, there is an increased chance for snow and ice to build up. Small changes in solar energy can tip the balance between summers in which the winter snow mass completely melts and summers in which the winter snow persists until the following winter. Due to the positions of Greenland, Antarctica, and the northern portions of Europe, Asia, and North America in Polar Regions, the Earth today is considered prone to ice age glaciations.
Proof for ice ages comes in a variety of forms, including rock scouring and scratching, glacial moraines, drumlins, valley cutting, and the deposition of till or tillites and glacial erratic. Successive glaciations be inclined to distort and erase the geological proof, making it difficult to interpret. It took some time for the current theory to be worked out. Analyses of ice cores and ocean sediment cores unmistakably show the record of glacial and interglacial over the past few million years.
The earliest hypothesized ice age is believed to have occurred around 2.7 to 2.3 billion years ago through the early Proterozoic Age.
Main article: Snowball Earth.
The most primitive well-documented ice age, and probably the most harsh of the last 1 billion years, occurred from 800 to 600 million years ago and it has been suggested that it formed a Snowball Earth in which permanent sea ice extensive to or very near the equator. It has been not compulsory that the end of this ice age was responsible for the subsequent Cambrian Explosion, though this theory is current and contentious.
The timing of ice ages all through geologic history is in part prohibited by the position of the continental plates on the surface of the Earth. When landmasses are determined near the Polar Regions, there is an increased chance for snow and ice to build up. Small changes in solar energy can tip the balance between summers in which the winter snow mass completely melts and summers in which the winter snow persists until the following winter. Due to the positions of Greenland, Antarctica, and the northern portions of Europe, Asia, and North America in Polar Regions, the Earth today is considered prone to ice age glaciations.
Proof for ice ages comes in a variety of forms, including rock scouring and scratching, glacial moraines, drumlins, valley cutting, and the deposition of till or tillites and glacial erratic. Successive glaciations be inclined to distort and erase the geological proof, making it difficult to interpret. It took some time for the current theory to be worked out. Analyses of ice cores and ocean sediment cores unmistakably show the record of glacial and interglacial over the past few million years.
Sunday, March 25, 2007
Banksia
Banksia is a genus of around 80 species in the plant family Proteaceae. They are native to Australia, occurring in all but the most arid areas. Easily recognized by their characteristic flower spikes and fruiting "cones", Banksia are a well-known Australian wildflower and a popular garden plant. They grow in forms varying from prostrate woody shrubs to trees up to 25 metres tall. They are normally known as Banksias or Australian Honeysuckle Trees.
Banksias grow as trees or woody shrubs. The largest trees, the Coast Banksia, B. integrifolia, and the River Banksia, B. seminuda, often grow over 15 metres tall, and may be up to 25 metres tall. Banksia species that grow as shrubs are typically erect, but there are some species that are prostrate, with branches that grow on or below the soil.
The leaves of Banksia vary greatly among species. Sizes vary from the narrow, 1–1½ centimetre long leaves of the Heath-leaved Banksia, B. ericifolia, to the very large leaves of the Bull Banksia, B. grandis, which may be up to 45 centimetres long. The leaves of most species have serrated edges, but a few, such as B. integrifolia, do not. Leaves are usually arranged along the branches in irregular spirals, but in some species they are crowded together in whorls.
Banksias are most without difficulty recognised by their characteristic flower spike, and the woody fruiting structures that appear after flowering. The flower spike consists of a central woody axis with a furry coating; it is usually held erect, but hangs down in a few species. This axis is enclosed in tightly-packed pairs of flowers, which are attached to the axis at right angles. A single flower spike may have over a thousand flowers.
Banksias grow as trees or woody shrubs. The largest trees, the Coast Banksia, B. integrifolia, and the River Banksia, B. seminuda, often grow over 15 metres tall, and may be up to 25 metres tall. Banksia species that grow as shrubs are typically erect, but there are some species that are prostrate, with branches that grow on or below the soil.
The leaves of Banksia vary greatly among species. Sizes vary from the narrow, 1–1½ centimetre long leaves of the Heath-leaved Banksia, B. ericifolia, to the very large leaves of the Bull Banksia, B. grandis, which may be up to 45 centimetres long. The leaves of most species have serrated edges, but a few, such as B. integrifolia, do not. Leaves are usually arranged along the branches in irregular spirals, but in some species they are crowded together in whorls.
Banksias are most without difficulty recognised by their characteristic flower spike, and the woody fruiting structures that appear after flowering. The flower spike consists of a central woody axis with a furry coating; it is usually held erect, but hangs down in a few species. This axis is enclosed in tightly-packed pairs of flowers, which are attached to the axis at right angles. A single flower spike may have over a thousand flowers.
Tuesday, March 20, 2007
Studio cameras
Most studio cameras stand on the floor, regularly with pneumatic or hydraulic mechanisms to adjust the height, and are typically on wheels. Any video camera when used along with other video cameras in a studio setup is controlled by a device well-known as CCU (camera control unit), to which they are linked via a Triax or Multicore cable. The camera control unit along with other equipments is installed in the production control room often documented as Gallery of the television studio. When used outside a studio, they are often on tracks. Initial models used analog technology, but digital models are becoming more common. Some studio cameras are light and small enough to be taken off the pedestal and used on a cameraman's shoulder, but they still have no recorder of their own and are cable-bound.
Wednesday, March 14, 2007
Haze
Haze is an atmospheric occurrence where dust, smoke and other pollutant particles obscure the usual clarity of the sky. It occurs when dust and smoke particles build up in relatively dry air. When weather conditions block the dispersal of smoke and other pollutants they concentrate and form a generally low-hanging shroud that impairs visibility and may become a respiratory health threat. Dense haze caused by industrial pollution is also known as smog.
Sources for haze particles include farming (ploughing in dry weather), traffic, industry, forest fires and peat field fire.
Seen from afar (e.g. approaching airplane), haze is brownish, while mist is more blueish-grey. While haze is formed in somewhat dryish air, in more humid air mist is formed, and the haze particles can even act as condensation nuclei for the mist droplets.
Sources for haze particles include farming (ploughing in dry weather), traffic, industry, forest fires and peat field fire.
Seen from afar (e.g. approaching airplane), haze is brownish, while mist is more blueish-grey. While haze is formed in somewhat dryish air, in more humid air mist is formed, and the haze particles can even act as condensation nuclei for the mist droplets.
Friday, March 09, 2007
Mirror
A mirror is an object whose surface has good specular reflection; that is, it is smooth sufficient to form an image. The most common type of mirror is the plane mirror, which has a flat surface. Curved mirrors are also used, to produce magnified or demagnified images or focus light.
The most common use of mirrors is for personal hygiene. However, mirrors are also used in scientific apparatus such as telescopes and lasers, as well as industrial machinery. Most mirrors are designed for visible light, however, mirrors intended for other wavelengths of electromagnetic radiation are also used, particularly in optical instruments.
The most common use of mirrors is for personal hygiene. However, mirrors are also used in scientific apparatus such as telescopes and lasers, as well as industrial machinery. Most mirrors are designed for visible light, however, mirrors intended for other wavelengths of electromagnetic radiation are also used, particularly in optical instruments.
Monday, March 05, 2007
The Leaning Tower of Pisa
The Leaning Tower of Pisa (Italian: Torre pendente di Pisa) or simply The Tower of Pisa (La Torre di Pisa) is the campanile, or self-supporting bell tower, of the cathedral of the Italian city of Pisa. It is situated behind the Cathedral and it is the third structure in Pisa's Campo dei Miracoli (field of Miracles).
Although planned to stand vertically, the tower began leaning to the southeast soon after the onset of construction in 1173 due to a poorly laid foundation and loose substrate that has permitted the foundation to shift.
The height of the tower is 55.86 m (183.27 ft) from the ground on the lowest side and 56.70 m (186.02 ft) on the highest side. The width of the walls at the base is 4.09 m (13.42 ft) and at the top 2.48 m (8.14 ft). Its weight is estimated at 14,500 tonnes. The tower has 294 steps.
The Tower of Pisa was a work of art, performed in three stages over a period of about 174 years. Construction of the first floor of the white marble campanile began on August 9, 1173, a period of military success and prosperity. This first floor is enclosed by pillars with classical capitals, leaning against blind arches. Today, it is still unscarred from centuries of weather and age.
Although planned to stand vertically, the tower began leaning to the southeast soon after the onset of construction in 1173 due to a poorly laid foundation and loose substrate that has permitted the foundation to shift.
The height of the tower is 55.86 m (183.27 ft) from the ground on the lowest side and 56.70 m (186.02 ft) on the highest side. The width of the walls at the base is 4.09 m (13.42 ft) and at the top 2.48 m (8.14 ft). Its weight is estimated at 14,500 tonnes. The tower has 294 steps.
The Tower of Pisa was a work of art, performed in three stages over a period of about 174 years. Construction of the first floor of the white marble campanile began on August 9, 1173, a period of military success and prosperity. This first floor is enclosed by pillars with classical capitals, leaning against blind arches. Today, it is still unscarred from centuries of weather and age.
Thursday, March 01, 2007
Mobile
A mobile or cellular telephone is a long-range, transferable electronic device for personal telecommunications over long distances. In addition to the standard voice function of a telephone, current mobile phones can support many additional services such as SMS for text messaging, email, packet switching for access to the Internet, and MMS for sending and receiving photos and video. Most current mobile phones attach to a cellular network of base stations (cell sites), which is in turn interconnected to the public switched telephone network (PSTN) (the exception are satellite phones).
Mobile phones are not distinct from cordless telephones, which usually operate only within a limited range of a specific base station. In principle, the term mobile phone includes such devices as satellite phones and pre-cellular mobile phones such as those operating via MTS which do not have a cellular network, whereas the linked term cell(ular) phone does not. In practice, the two terms are used almost interchangeably.
Mobile phones are not distinct from cordless telephones, which usually operate only within a limited range of a specific base station. In principle, the term mobile phone includes such devices as satellite phones and pre-cellular mobile phones such as those operating via MTS which do not have a cellular network, whereas the linked term cell(ular) phone does not. In practice, the two terms are used almost interchangeably.
Friday, February 23, 2007
Manhattan
Manhattan refers to both the Island of Manhattan and encompasses most of the Borough of Manhattan, one of the five boroughs of New York City. The viable, financial, and cultural center of the city, Manhattan has many famous landmarks, tourist attractions, museums and universities. It is also home to the control center of the United Nations and the seat of city government.
The borough of Manhattan is coterminous with New York County, which is also the most densely populated county in the United States. Postal addresses within the borough are typically chosen as "New York, NY."
Manhattan has the biggest central business district in the United States and is the site of most of the city's corporate headquarters and the New York Stock Exchange. Although its population is third biggest of the five boroughs, after Brooklyn and Queens, and it is geographically the smallest, Manhattan is the borough that many visitors most personally associate with New York City.
The borough of Manhattan is coterminous with New York County, which is also the most densely populated county in the United States. Postal addresses within the borough are typically chosen as "New York, NY."
Manhattan has the biggest central business district in the United States and is the site of most of the city's corporate headquarters and the New York Stock Exchange. Although its population is third biggest of the five boroughs, after Brooklyn and Queens, and it is geographically the smallest, Manhattan is the borough that many visitors most personally associate with New York City.
Monday, February 19, 2007
Indian culture
Indian culture can be classified into many different form which are existent in their totality throughout the territory of India. The culture of India has been influenced by different religions and customs of the world, which resulted in the mingling of religious values, folk idioms and art forms. While the religious influence is relatively evident in the "classical" Indian culture mostly found in smaller towns and villages, the urban India is now widely influenced globalization.
The cultural policy of the Government of India has three most important objectives. One of them is to preserve the cultural heritage of India; to repeat Indian art consciousness amongst countrymen and to promote high standards in innovative and performing arts fields
The cultural policy of the Government of India has three most important objectives. One of them is to preserve the cultural heritage of India; to repeat Indian art consciousness amongst countrymen and to promote high standards in innovative and performing arts fields
Tuesday, February 13, 2007
Eye movement
Animals with compound eyes have a wide field of vision, allowing them to look in many directions. To see more, they have to move about their entire head or even body.The visual system in the brain is too slow to process that information if the images are slipping across the retina at more than a few degrees per second. Thus, for humans to be able to see while moving, the brain must compensate for the motion of the head by turning the eyes. Another complication for vision in frontal-eyed animals is the development of a small area of the retina with a very high visual sharpness. This area is called the fovea, and covers about 2 degrees of visual angle in people. To get a clear view of the world, the brain must turn the eyes so that the image of the object of regard falls on the fovea. Eye movements are thus very essential for visual perception, and any failure to make them correctly can lead to serious visual disabilities.Having two eyes is an added complication, because the brain must point both of them accurately enough that the object of regard falls on corresponding points of the two retinas; otherwise, double vision would occur. The movements of different body parts are controlled by striated muscles acting around joints. The movements of the eye are no exception, but they have special advantages not shared by skeletal muscles and joints, and so are considerably different.
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