Friday, December 28, 2007

Cast iron

Cast iron usually refers to grey cast iron, but can mean any of a group of iron-based alloys containing more than 2% carbon. It is made by remelting pig iron, often along with substantial quantities of scrap iron and scrap steel, and taking various steps to remove undesirable contaminants such as phosphorus and sulfur. Carbon and silicon content are reduced to the desired levels, which may be anywhere from 2% to 3.5% for carbon and 1% to 3% for silicon depending on the application. Other elements are then added to the melt before the final form is produced by casting.
Iron is most commonly melted in a small blast furnace known as a cupola. After melting is complete, the molten iron is removed or ladled from the forehearth of the blast furnace. This process is thought to have been devised by the late 18th century ironmaster John Wilkinson, whose innovative ideas revolutionized the field of metallurgy. Previously, iron was melted in an air furnace, which is a type of reverberatory furnace.

Monday, December 17, 2007


In finance, a bond is a debt security, in which the certified issuer owes the holders a debt and is obliged to repay the principal and interest (the coupon) at a later date, termed maturity. Other conditions may also be attached to the bond issue, such as the obligation for the issuer to provide certain information to the bond holder, or limits on the behavior of the issuer. Bonds are usually issued for a fixed term more than ten years, U.S. Treasury securities issue debt with life of ten years or more, which is a bond, and New debt between one year and ten years is a "note", and new debt less than a year is a "bill".

Sunday, December 02, 2007

Antoine Lavoisier

Antoine Lavoisier was one of the well known French scientists and was a chief government official. His theories of combustion, his growth of a way to categorize the fundamentals and the first new textbook of chemistry led to his being known as the father of modern chemistry. He contribute too much of investigate in the field of chemistry. He is quote for saying, nothing is lost, nothing is created, and everything is distorted. He bore in Paris, France on Aug. 26, 1743. When he was eleven years old he attends a college called Mazain, For Lavoisier's last two years in college he creates a massive deal of attention in science.
He received an excellent teaching and developed an attention in all branches of science, particularly chemistry. Abbe Nicolas Louis de Lacaill trained Lavoisier regarding meteorological examination. On 1763 Lavoisier anticipated his bachelor's degree and on 1764 a licentiate which allowed him to practice his profession. In his extra time he studied books of science and his first paper was written about gypsum, also familiar by hydrated calcium sulfate and he describes its chemical and physical property.

Sunday, October 28, 2007


Metabolism is the total set of chemical reactions that occur in living cells. These processes are the source of life, allowing cells to grow and reproduce, maintain their structures, and react to their environments. Metabolism is frequently divided into two categories. Catabolic reactions yield energy, an example being the stop working of food in cellular respiration. Anabolic reactions, on the other hand, use this energy to construct mechanism of cells such as proteins and nucleic acids.

The chemical reactions of metabolism are organized into metabolic pathways, in which one chemical is distorted into another by a series of enzymes. Enzymes are vital to metabolism because they allow cells to drive desirable but thermodynamically unfavorable reactions by combination them to favorable ones. Enzymes also agree to the regulation of metabolic pathways in response to changes in the cell's environment or signals from other cells.

Friday, October 05, 2007


A firm which export and import products are calls merchandise. This is also a method for the merchandising business to earn their profit. Merchandising businesses are dissimilar from service businesses. Merchandising business have goods on hand and resell to customers, it is called inventory. However, inventory is recorded day to day under periodic or everlasting methods. Further, very businesses dealings involved the Goods and Service Tax. This essay is set out to explore the operation of merchandising business, the two methods which utilize to record inventory transactions and the application of Goods and Service Tax.
In merchandising businesses stock on hand, which is also called inventory, stock in trade or stock, is a very important asset. Thus, it is necessary to keep the inventory safe from damage, decline and theft. This requires the structure of storage areas and the employment of person’s expert in handling inventories.

Monday, September 24, 2007

Types of software

Practical computer systems partition software into three major classes: system software, programming software and application software, although the division is subjective, and often blurred.

* System software is one of the major class helps run the computer hardware and computer system. It includes working systems, device drivers, analytical tools, servers, windowing systems, utilities and more. The intention of systems software is to protect the applications programmer as much as possible from the details of theexacting computer complex being use, especially memory and other hardware features, and such accessory procedure as communications, printers, readers, displays, keyboards, etc.

* Programming software usually provide tools to support a programmer in writing computer programs and software with different programming languages in a more suitable way.The tools comprise text editors, compilers, interpreters, linkers, debuggers, and so on, An incorporated development environment merge those tools into a software bundle, and a programmer may not need to type various command for compiling, interpreter, debugging, tracing, and etc., because the IDE typically has an sophisticated graphical user interface, or GUI.

* Application software allows humans to complete one or more explicit tasks. typical applications include manufacturingautomation, business software, educational software, medical software, databases and computer games. Businesses are possibly the biggest users of application software, but approximately every field of human action now uses some form of application software. It is used tocomputerizeall sorts of functions.

Monday, September 10, 2007

Mobile phone culture or customs

In fewer than twenty years, mobile phones have gone from being rare and expensive pieces of equipment used by businesses to a pervasive low-cost personal item. In many countries, mobile phones now outnumber land-line telephones, with most adults and many children now owning mobile phones. In the United States, 50% of children own mobile phones. It is not uncommon for young adults to simply own a mobile phone instead of a land-line for their residence. In some developing countries, where there is little existing fixed-line infrastructure, the mobile phone has become widespread. According to the CIA World Fact book the UK now has more mobile phones than people.

With high levels of mobile telephone penetration, a mobile culture has evolved, where the phone becomes a key social tool, and people rely on their mobile phone address book to keep in touch with their friends. Many people keep in touch using SMS, and a whole culture of "texting" has developed from this. The commercial market in SMS's is growing. Many phones even offer Instant Messenger services to increase the simplicity and ease of texting on phones. Cellular phones in Japan, offering Internet capabilities such as NTT DoCoMo's i-mode, offer text messaging via standard e-mail.

Sunday, September 02, 2007


Orange—specifically, sweet orange—refers to the citrus tree Citrus sinensis and its fruit. The orange is a hybrid of ancient cultivated origin, possibly between pomelo and tangerine. It is a small flowering tree growing to about 10 m tall with evergreen leaves, which are arranged alternately, of ovate shape with crenulated margins and 4–10 cm long. The orange fruit is hesperidia, a type of berry.

Sunday, August 26, 2007

Electron microscopes

Electron microscopes, which use beams of electrons as a substitute of light, are designed for very high magnification usage. Electrons, which have a much smaller wavelength than visible light, allow a much higher resolution. The main limitation of the electron beam is that it must pass through a vacuum as air molecules would otherwise scatter the beam.

Sunday, August 19, 2007

Persian orange

The Persian orange, grown-up widely in southern Europe after its introduction to Italy in the 11th century, was bitter. Sweet oranges bring to Europe in the 15th century from India by Portuguese traders, rapidly displaced the bitter, and are now the most common variety of orange cultivated. The sweet orange will grow to different sizes and colors according to local conditions, most commonly with ten carpel’s, or segments, inside.

Sunday, August 12, 2007


A solstice occur twice a year, whenever Earth's axis tilts the most toward or away from the Sun, causing the Sun to be farthest north or south at noon. The name is derivative from Latin sol (sun) and sistere (to stand still), because at the solstice, the Sun stands still in declination, that is, its movement north or south is minimal. The term solstice can also be used in a wider sense as the date (day) that such a passage happens. The solstices, together with the equinoxes, are related to the seasons. In some languages they are considered to start or separate the seasons; in others they are considered to be center points.

Friday, August 03, 2007

Pedestrian crossings

Pedestrians must often traverse from one side of a road to the other, and in doing so may come into the way of vehicles traveling on the road. In many places pedestrians are completely left to look after themselves, that is, they must observe the road and cross when they can see that no traffic will threaten them. Busier cities usually provide pedestrian crossings, which are strips of the road where pedestrians are expected to traverse.

Wednesday, July 25, 2007

Apple Computer

Apple Computer, Inc. NASDAQ: AAPL is a Silicon Valley company based in Cupertino, California, whose nucleus business is computer technologies. Apple helped originate the personal computer revolution in the 1970s with the Apple II microcomputer and has since further shaped it with the Macintosh. Apple is known for its original, well-designed hardware, such as the iPod and iMac, as well as software offerings exemplified through iTunes as part of the iLife suite and Mac OS X, its flagship operating system.

Sunday, July 15, 2007

Krill fishery

Krill fishery is the profitable fishery of krill, small shrimp-like marine animals that live in the oceans world-wide. Estimates for how much krill there is vary wildly, depending on the methodology used. They range from 125–725 million tones of biomass globally. The total global harvest of krill from all fisheries amounts to 150 – 200,000 tones annually, mainly Antarctic krill (Euphausia superb) and North Pacific krill (E. Pacifica).

Krill are rich in protein (40% or more of dry weight) and lipids (about 20% in E. superb). Their exoskeleton amounts to some 2% of dry weight of chitin. They also contain traces of a wide array of hydrolytic enzymes such as proteases, carbohydrates, nucleases and phospholipids, which are intense in the digestive gland in the cephalothoraxes of the krill.

Tuesday, July 10, 2007

Time server

A time server is a server computer that reads the actual time from a orientation clock and distributes this information to its clients using a computer network. The time server may be a local network time server or an internet time server. The majority important and widely-used protocol for distributing and synchronizing time is the Network Time Protocol, though other less-popular or outdated time protocols continue in use. The time reference used by a time server could be another time server on the network or the Internet, a connected radio clock or an atomic clock. The most common true time source is a GPS or GPS master clock. Time servers are sometimes multi-purpose network servers, dedicated network servers, or dedicated devices. All a dedicated time server does is provide accurate time.

Monday, July 02, 2007


MS-DOS (MicroSoft Disk Operating System) is an operating system commercialized by Microsoft. It was the commonly used member of the DOS family of operating systems and was the dominant operating system for the PC compatible platform during the 1980s. It has gradually been replaced on consumer desktop computers by a variety of generations of the Windows operating system.

MS-DOS was initially released in 1981 and had eight major versions released before Microsoft stopped development in 2000. It was the key product in Microsoft's growth from a programming languages company to varied software development firm, providing the company with essential revenue and marketing resources.

Friday, June 29, 2007

Applied Micro Circuits Corporation

Applied Micro Circuits Corporation is a fables semiconductor company scheming network and embedded Power Architecture, optical transport and storage solutions. They bought assets, IP and engineers concerning the PowerPC 400 microprocessors from IBM in 2004 for $227 million and they now market the processors under their own name. The deal also included access to IBM's SoC design methodology and advanced CMOS process technology.

3ware is a producer of RAID controllers and storage products. Founded as an self-governing company in 1997, it was acquired by AMCC in April 2004.This division has usually been focused on SATA and PATA RAID devices. They were one of the pioneers in implementing "multi-lane" cabling for RAID systems which greatly reduced cable difficulty in systems with many hard drives.

Sunday, June 24, 2007

Shrimp fishery

A shrimp fishery is a fishery directed toward harvesting either shrimp or prawns. Fisheries do not usually differentiate between the two taxa, and the terms are used interchangeably. This article therefore refers to the catching of either shrimp or prawns.

A number of the larger species, including the Atlantic white shrimp (Penaeus setiferus), are caught commercially and used for food. Recipes utilizing shrimp form part of the cuisine of many cultures: examples include jambalaya, okonomiyaki, poon choi, bagoong, Kerala and scampi.
Preparing shrimp for consumption usually involves removing the shell, tail, and "sand vein". As with other seafood, shrimp is high in calcium, protein and low in food energy.
Shrimp and prawns are versatile ingredients, and are often used as an accompaniment to fried rice. Common methods of preparation comprise baking, boiling and frying. As stated in the movie Forrest Gump

Tuesday, June 19, 2007


Grafting is a method of plant propagation extensively used in horticulture, where the tissues of one plant are encouraged to fuse with those of another. It is most usually used for the propagation of trees and shrubs grown commercially. In most cases, one plant is chosen for its roots, and this is called the stock or rootstock. The other plant is chosen for its stems, leaves, flowers, or fruits and is called the scion.In stem grafting, a common grafting method, a shoot of a chosen, desired plant cultivar is grafted onto the stock of another type. In another common form called budding, a dormant side bud is grafted on the stem of another stock plant, and when it has fused successfully, it is encouraged to grow by cutting out the stem above the new bud.For successful grafting to take place, the vascular cambium tissues of the stock and scion plants must be located in contact with each other. Both tissues must be kept alive till the graft has taken, typically a period of a few weeks. Successful grafting only requires that a vascular connection takes place between the two tissues. A physical weak point often still occurs at the graft, because the structural tissue of the two distinct plants, such as wood may not fuse.

Tuesday, June 12, 2007

Water abstraction

Water abstraction, or water extraction, is the process of taking water from any source, either temporarily or permanently. Most water is used for irrigation or treatment to produce drinking water.Depending on the environmental legislation in the relevant country, controls may be located on abstraction to limit the amount of water that can be removed. Over abstraction can lead to rivers drying up or the level of groundwater aquifers reducing unacceptably.The science of hydrogeology is used to assess safe abstraction levels.

Thursday, June 07, 2007


Electronic watches require electricity as a power source. Some mechanical movements and hybrid electronic-mechanical actions also require electricity. Usually the electricity is provided by a replaceable battery. The first use of electrical power in watches was as replacement for the mainspring, in order to remove the need for winding. The first electrically-powered watch, the Hamilton Electric 500, was released in 1957 by the Hamilton Watch Company of Lancaster, Pennsylvania. Batteries for watches are specially designed for their purpose. They are very small and provide tiny amounts of power incessantly for very long periods. In most cases, replacing the battery requires a trip to a watch-repair shop or watch dealer; this is especially true for watches that are designed to be water-resistant, as special tools and procedures are required to ensure that the watch remains water-resistant after battery replacement. Silver-oxide and lithium batteries are popular today; mercury batteries, formerly quite common, are no longer used, for ecological reasons. Cheap batteries may be alkaline, of the same size as silver-oxide but providing shorter life.

Sunday, June 03, 2007

Titan Industries

Titan Industries is the world's sixth largest wrist watch manufacturer and India's leading producer of watches under the Titan and Sonata brand names. It is a joint business enterprise between India's most respected business organization - the Tata Group and the Tamil Nadu Industrial Development Corporation. Its product portfolio includes watches, clocks, accessories and jewelers, in both contemporary and traditional designs. It exports watches to about 32 countries around the world with manufacturing facilities in Hosur, Dehradun, Goa and manufactures precious jewelers under the Tanishq brand name, making it India's only national jewelers brand. It is an additional of the Tata Group.

Tuesday, May 29, 2007

American carrom

American carrom is an alternative on carrom derived in America by missionaries to the East, around 1890. Believing that the game required restructuring for Western tastes, a Sunday school teacher named Henry Haskell altered the game. Much of the game is the same, but the striker's weight is reduced and the carrom men are smaller. Generally, instead of disks of solid wood, ivory, or acrylic, carrom men are rings, originally of wood but today commercially made of light plastic. In addition, as an alternative to using the fingers to flick the striker,American carrom uses miniature cue sticks. American carrom boards also have pockets built into the corners, rather than circular holes in the board, to make pocketing easier. While traditionally made boards vary widely, current commercially-produced American carrom boards are 28 inches square, are printed with checkerboard and backgammon patterns, among others, and are sold with checkers, chess pieces, skittles, etc., to allow other games to be played on the same board. Often, these boards are also built to play crokinole.

Monday, May 21, 2007


A joystick is a personal computer tangential or general control device consisting of a handheld stick that pivots about one end and transmits its angle in two or three dimensions to a computer. Joysticks are often used to control video games, and generally have one or more push-buttons whose state can also be read by the computer. The term joystick has become a synonym for game controllers that can be connected to the computer since the computer defines the input as a "joystick input”. Apart for controlling games; joysticks are also used for controlling machines such as elevators, cranes, trucks, powered wheelchairs and some zero turning radius lawn mowers. More lately miniture joysticks have been adopted as navigational devices for smaller electronic apparatus such as mobile phones.

Tuesday, May 15, 2007


In chemistry, a metal is a constituent that readily loses electrons to form positive ions and has metallic bonds between metal atoms. Metals form ionic bonds with non-metals. They are sometimes described as a web of positive ions surrounded by a cloud of delocalized electrons. The metals are one of the three groups of elements as eminent by their ionization and bonding properties, along with the metalloids and nonmetals. On the periodic table, a diagonal line drawn from boron separates the metals from the nonmetals. Most elements on this line are metalloids, sometimes called semi-metals; elements to the lower left are metals; elements to the upper right are nonmetals.

A modern definition of metals is that they have overlapping conveyance bands and valence bands in their electronic structure. This definition opens up the category for metallic polymers and other organic metals, which have been prepared by researchers and employed in high-tech devices. These synthetic materials often have the characteristic silvery-grey reflective ness of elemental metals.

Wednesday, May 09, 2007

Hard Disk

A hard disk is a non-volatile storage device which stores digitally programmed data on rapidly rotating platters with magnetic surfaces. Strictly speaking, "drive" refers to a device that drives (removable) media, such as a tape drive or (floppy) disk drive, although a hard disk contains fixed (non-removable) media. Recently the hard disk has become more commonly known as the "hard drive".

Hard disks were initially developed for use with computers. In the 21st century, applications for hard disks have extended beyond computers to consist of digital video recorders, digital audio players, personal digital assistants, digital cameras, and video game consoles. In 2005 the first mobile phones to contain hard disks were introduced by Samsung Group and Nokia. The need for large-scale, reliable storage, independent of a particular device, led to the beginning of configurations such as RAID, hardware such as network attached storage (NAS) devices, and systems such as storage area networks (SANs) for efficient access to large volumes of data.

Thursday, May 03, 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.

Sunday, April 29, 2007


Nanotechnology is a pasture of applied science and technology covering a wide range of topics. The main unifying premise is the control of matter on a scale smaller than 1 micrometer, normally between 1-100 nanometers, as well as the manufacture of devices on this same length scale. It is a highly multidisciplinary field, drawing from fields such as colloidal science, device physics, and supramolecular chemistry. Much hypothesis exists as to what new science and technology might result from these lines of research. Some view nanotechnology as a marketing term that describes pre-existing lines of research applied to the sub-micron size scale.

In spite of the apparent ease of this definition, nanotechnology actually encompasses diverse lines of inquiry. Nanotechnology cuts across many disciplines, together with colloidal science, chemistry, applied physics, materials science, and even mechanical and electrical engineering. It could variously be seen as an extension of existing sciences into the nanoscale, or as a recasting of existing sciences using a newer, more recent term. Two major approaches are used in nanotechnology: one is a "bottom-up" approach where materials and devices are built from molecular components which gather themselves chemically using principles of molecular gratitude; the other being a "top-down" approach where nano-objects are constructed from larger entities without atomic-level control.

Monday, April 23, 2007


Water is a tasteless, odorless, and nearly colorless substance in its pure form that is essential to all known forms of life and is known also as the most worldwide solvent. Water is a plentiful essence on Earth. It exists in many places and forms: mostly in the oceans and polar ice caps, but also as clouds, rain water, rivers, freshwater aquifers, and
sea ice. On the planet, water is always moving through the cycle linking vanishing, rainfall, and runoff to the sea.
Water that humans consume is called potable water. This natural resource is becoming scarcer in certain places as human population in those places increases, and its availability is a major social and economic concern.

A surprising substance
Changing appearances
Drinking water for more details on this topic, see Category: Forms of water.
Water takes many different shapes on earth: water vapor and clouds in the sky, waves and icebergs in the sea, glaciers in the mountain, aquifers in the ground, to name but a few. Through evaporation, precipitation, and runoff, water is constantly flowing from one form to another, in what is called the water cycle.
Because of the value of precipitation to agriculture, and to mankind in general, we give different names to its various forms: while rain is common in most countries, other phenomena are quite surprising when seen for the first time: hail, snow, fog or dew for example. When properly lit, water drops in the air can refract sunlight to create rainbows.
Similarly, water runoffs have played main roles in human history: rivers and irrigation brought the water needed for agriculture. Rivers and the seas offered prospect for travel and commerce. Through erosion, runoffs played a major part in shaping our environment provided that river valleys and deltas which provide rich soil and level ground for the enterprise of population centers.
Water also infiltrates the ground and goes into aquifers. This groundwater later flows back to the surface in springs or more outstandingly in hot springs and geysers. Groundwater is also extracted unnaturally in wells.

Thursday, April 19, 2007

Transistor radio

The transistor radio is a small radio receiver.RCA demonstrated a prototype transistor radio in 1952. The first commercial transistor radio, the Regency TR-1, was announced on October 18, 1954 by the Regency Division of Industrial Development Engineering Associates of Indianapolis, Indiana and put on sale in November of 1954. It cost $49.95 (the equivalent of $361 in year-2005 dollars) and sold approximately 100,000 units.The use of transistors in its place of vacuum tubes as the amplifier elements meant that the device was much smaller and necessary far less power to operate than a tubed radio. The characteristic portable radio of the fifties was about the size and weight of a small laptop computer, and contained several heavy batteries: one or more A batteries to heat the tube filaments and a large 45 to 90 volt B battery for plate voltage. By comparison, the "transistor" was about the size and weight of today's cassette-playing Walkman and operated off a single compact 9 V battery. The now-familiar 9 V battery was introduced particularly for powering transistor radios.

Tuesday, April 10, 2007

Postal Marking

Less ordinary types include forwarding addresses, routing annotations, warnings, postage due notices and explanations, such as for damaged or delayed mail. A key part of postal history is the recognition of postal markings, their purpose, and period of use.

Service marks give information to the sender, recipient, or another post office. Advice marks notify about forwarding, misspending, and letters received in bad condition, letters received too late for delivery by a certain time, or the reason for a delay in mail delivery. Dead letter offices would use various markings to keep track of their progress in finding the addressee, such as a document that the letter had been advertised in the local newspaper. The tracking procedure for registered mail may entail multiple marks and notations.

Auxiliary marks are functional by an organization other than the postal administration. For instance, 19th century mail delivery often relied on a mix of private ships, steamboats, stagecoaches, railroads, and other transportation organizations to transfer mail. Many of these organizations applied their own markings to each item, occasionally saying simply "STEAMSHIP" or some such, while others had elaborate designs. Similar direction-finding notations were also used in the early days of airmail.

The traditional way to be valid a postal marking is with the use of a rubber or metal hand stamp; handwritten notations are sometimes seen for unusual situations or in very small post offices. In the United States, modern postal markings may appear in the form of yellow paste labels with the text printed on them. Many postal administrations now have the ability to print inkjet observations directly onto a cover, either as a barcode for reading by other equipment, or as text.

Friday, April 06, 2007


The Goshawk is an average large bird of quarry in the family Accipitridae which also includes many other diurnal raptors such as eagles, buzzards and harriers.

It is an extensive species all through the moderate parts of the northern hemisphere. In North America it is named as the Northern Goshawk. It is typically inhabitant, but birds from colder regions of north Asia and Canada journey south for the winter.

Goshawk in flight this species nests in trees, building a new nest each year. It hunts birds and mammals in woodland, relying on revelation as it flies from a perch or hedge-hops to catch its quarry ignorant. Animals as large as hares and Pheasant are taken. Its call is a ferocious screech. Many older goshawks reject to attack hares, if it was earlier seriously kicked by a hare which it tried to catch.

This bird is a raptor with short large wings and a long tail, both adaptations to maneuvering through trees. The male is blue-grey above and banned grey below, 49-56 cm long with a 93-105 cm wingspan. The much larger female is 58-64 cm long with a 108-127 cm wingspan, slate grey above grey below. The youthful is brown above and barred brown below. The flight is a characteristic "slow flap – slow flap – straight glide".
In Eurasia, the male is confusable with a female Sparrow hawk, but is superior, much bulkier and has moderately longer wings. In spring, he has an impressive roller-coaster display, and this is the best time to see this enigmatic forest bird

Monday, April 02, 2007


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.

Thursday, March 29, 2007

Video Camera
A professional video camera (often called a "television camera"
even though the use has extend) is a high-end tool for video
recording electronic moving images (as opposed to a film camera,
that records the images on film). Formerly developed for use in
television studios, they are now normally used for corporate and
educational videos, music videos, direct-to-video movies, etc.
Not as much of advanced video cameras used by customers are
often referred to as camcorders.
There are two kind of professional video cameras: High end
portable, video recording cameras (which are, confusingly,
called camcorders too) used for ENG image gaining, and studio
cameras which lack the recording capability of a camcorder, and
are often fixed on studio pedestals.
Professional video cameras confine and transfer two dimensional
images serially, at specified capture rates, usually in the
visible range of the electromagnetic spectrum.
Most studio cameras situate on the floor, usually with pneumatic
or hydraulic mechanisms to regulate the height, and are usually
on wheels

Friday, March 23, 2007


The telephone or phone (Greek: tele = far away and phone = voice) is a telecommunications device to transmits and receives sound (most commonly voice and speech) through great distances. Most telephones function by means of electric signals over a complex public switched telephone network of equipment which allows almost any phone user to speak to almost any other.
Until relatively recently the word telephone could generally be assumed to refer to a landline phone. Now, cordless telephones and cell phones have become sufficiently common that no such presumption can be made. There are four principal means by which telephone signals are transmitted: throughout a traditional landline which uses physical dedicated wire connections; wireless or Radiotelephony, which transmits messages using either analog or digital radio signals; satellite telephones which bounce signals off of telecommunications satelites; and voice over internet protocol (VOIP) telephones, which use broadband internet cables.
The electric telephone is recognized to various inventors. The actual history is a subject of complex dispute. Among others Antonio Meucci, Philip Reis, and Alexander Graham Bell are all credited with inventing.

Monday, March 19, 2007


Film is a term that encompasses motion pictures as individual projects, as well as the field in general. The source of the name comes from the fact that photographic film (also called filmstock) has historically been the main medium for recording and displaying motion pictures. Many other terms exist — motion pictures, the silver screen, photoplays, picture shows, flicks — and most commonly movies. Academics and the English-speaking international society prefer to use film or "cinema", due to the colloquial nature of these other terms.
Films are created by recording actual people and objects with cameras, or by creating them using animation techniques and/or special effects. They include a series of individual frames, but when these images are shown quickly in succession, the illusion of motion is given to the viewer. Flickering between frames is not seen due to an effect known as persistence of vision — whereby the eye retains a visual image for a fraction of a second after the source has been removed. Perhaps of more relevance is what causes the perception of motion — a psychological effect known as beta movement.

Tuesday, March 13, 2007


Beauty in nature is a general theme in modern life and in art, and books emphasizing beauty in nature fill large sections of libraries and bookstores. That nature has been depicted and famous by so much art, photography, poetry and other literature shows the strength with which many people associate nature and beauty. Why this association exists, and what the association consists of, is studied by the branch of philosophy called aesthetics. Beyond certain basic characteristics that many philosophers agree about to explain what is seen as beautiful, the opinions are almost endless.Many scientists, who study nature in more specific and organized ways, also share the conviction that nature is beautiful; the French mathematician, Jules Henri Poincaré (1854-1912) said:
The scientist does not study nature because it is useful; he studies it because he delights in it, and he delights in it because it is beautiful.
If nature were not beautiful, it would not be worth knowing, and if nature were not worth meaningful, life would not be worth living. Of course I do not here speak of that beauty which strikes the senses, the beauty of character and of appearance; not that I undervalue such beauty, far from it, but it has not anything to do with science; I mean that profounder beauty which comes from the harmonious order of the parts and which a pure intelligence can grasp.
A general classical idea of beautiful art involves the word mimesis, the imitation of nature. Also in the realm of ideas about beauty in nature is that the perfect is indirect through symmetry, equal division, and other perfect mathematical forms and notions.

Thursday, March 08, 2007


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.

Sunday, March 04, 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.

Tuesday, February 27, 2007


A gemstone is prized particularly for great beauty or perfection so appearance is almost always the most significant attribute of gemstones. Characteristics that make a stone beautiful or attractive are colour, unusual optical phenomena within the stone, an exciting inclusion such as a fossil, rarity, and sometimes the form of the natural crystal. Diamond is prized very much as a gemstone since it is the hardest naturally occurring substance known and is able to reflect light with fire and sparkle when faceted. However, diamonds are far from rare with millions of carats mined each year.
Traditionally, general gemstones were classified into precious stones (cardinal gems) and semi-precious stones. The former class was largely determined by a history of ecclesiastical, devotional or ceremonial use and rarity. Only five types of gemstones were considered precious: diamond, ruby, sapphire, emerald, and amethyst. In current usage by gemologists, all gems are considered precious, although four of the five original "cardinal gems" (excluding the now-common amethyst) are typically—but not always—the most valuable.
Rare or unusual gemstones, usually meant to include those gemstones which occur so infrequently in gem quality that they are only just known except to connoisseurs, include andalusite, axinite, cassiterite, clinohumite and iolite.

Thursday, February 22, 2007


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.

Sunday, February 18, 2007


In Hinduism, the Sanskrit words most strongly corresponding to soul are "Jiva", meaning the individual soul or qualities, and "Atman", which can also mean spirit or even God. The Atman is seen as the section of Brahman within us. Hinduism contains many variant beliefs on the source, purpose, and fate of the soul. For example, advaita or non-dualistic conception of the soul accords it union with Brahman, the complete uncreated (roughly, the Godhead), in eventuality or in pre-existing fact. Dvaita or dualistic concepts reject this, instead identifying the soul as a different and incompatible substance.
The Bhagavad Gita, one of the most major puranic scriptures, refers to the religious body or soul as Purusha (see also Sankhya philosophy). The Purusha is division and parcel of God, is unchanging (is never born and never dies), is indestructible, and, though basically indivisible, can be described as having three characteristics:
(i) Sat (reality or existence)
(ii) Chit (realization or knowledge)
(iii) Ananda (delight)

Friday, February 09, 2007

Infrared (IR) emission is electromagnetic emission of a wavelength longer than that of noticeable light, but shorter than that of radio waves. The name means "below red" (from the Latin infra, "below"), red being the color of detectable light of longest wavelength. Infrared radiation spans three instructions of magnitude and has wavelengths between about 750 nm and 1 mm.
These divisions are suitable by the different human response to this radiation: near infrared is the area closest in wavelength to the radiation detectable by the human eye, mid and far infrared are gradually further from the visible regime. Other definitions follow different physical mechanisms (emission peaks, vs. bands, water absorption) and the newest follow technical reasons (The common silicon detectors are sensitive to about 1,050 nm, while Inga As sensitivity starts around 950 nm and ends between 1,700 and 2,600 nm, depending on the specific configuration). Unfortunately the international standards for these specifications are not currently obtainable.
The boundary between visible and infrared light is not precisely defined. The human eye is markedly less responsive to light above 700 nm wavelength, so longer frequencies make irrelevant contributions to scenes illuminated by common light sources. But particularly strong light (e.g., from lasers, or from bright daylight with the visible light removed by colored gels [1]) can be detected up to approximately 780 nm, and will be apparent as red light. The onset of infrared is defined (according to different standards) at different values typically between 700 nm and 780 nm.