ATM'S


An automated teller machine (ATM) also known as a Cash Point  is a computerised telecommunications device that provides the clients of a financial institution with access to financial transactions in a public space without the need for a cashier, human clerk or bank teller. ATMs are known by various other names including ATM Machine, automatic banking machine, cash machine and various regional variants derived from trademarks on ATM systems held by particular banks. Invented by IBM, the first ATM was introduced in December 1972 at Lloyds Bank in the UK. On most modern ATMs, the customer is identified by inserting a plastic ATM card with a magnetic stripe or a plastic smart card with a chip, that contains a unique card number and some security information such as an expiration date. Authentication is provided by the customer entering a personal identification number.

Using an ATM, customers can access their bank accounts in order to make cash withdrawals, credit card cash advances and check their account balances as well as purchase prepaid cellphone credit. If the currency being withdrawn from the ATM is different from that which the bank account is denominated in , the money will be converted at a wholesale exchange rate. Thus, ATMs often provide the best possible exchange rate for foreign travelers and are heavily used for this purpose as well.

The idea of self-service in retail banking developed through independent and simultaneous efforts in Japan, Sweden, the United Kingdom and the United States. In the USA, Luther George Simjian has been credited with developing and building the first cash dispenser machine. There is strong evidence to suggest that Simjian worked on this device before 1959 while his 132Nd patent was first filed on 30 June 1960. The rollout of this machine, called Bankograph, was delayed a couple of years. This was due in part to Simjian's Reflectone Electronics Inc. being acquired by Universal Match Corporation. An experimental Bankograph was installed in New York City in 1961 by the City Bank of New York but removed after 6 months due to the lack of customer acceptance. The Bankograph was an automated envelope deposit machine and it did not have cash dispensing features.

A first cash dispensing device was used in Tokyo in 1966. Although little is known of this first device, it seems to have been activated with a credit card rather than accessing current account balances. It was followed in 1967 by a machine in Uppsala.
ATMs are placed not only near or inside the premises of banks but also in locations such as shopping malls, airports, grocery stores, petrol stations, restaurants or anywhere frequented by large numbers of people. There are two types of ATM installations- on- and off-premise. On premise ATMs are typically more advanced, multi-function machines that complement a bank branch's capabilities and are thus more expensive. Off-premise machines are deployed by financial institutions and Independent Sales Organizations where there is a simple need for cash, so they are generally cheaper mono-function devices. In Canada, ABMs not operated by a financial institution are known as "White Label ABMs". In North America banks often have drive-through lanes providing access to ATMs. Many ATMs have a sign above them, called a topper, indicating the name of the bank or organization owning the ATM and possibly including the list of ATM networks to which that machine is connected.


Most ATMs are connected to interbank networks, enabling people to withdraw and deposit money from machines not belonging to the bank where they have their account or in the country where their accounts are held. Some examples of interbank networks include PULSE, PLUS, Interswitch, STAR and LINK.
ATM's rely on authorization of a financial transaction by the card issuer or other authorizing institution via the communications network. This is often performed through an ISO 8583 messaging system.

Many banks charge ATM usage fees. In some cases, these fees are charged solely to users who are not customers of the bank where the ATM is installed.

COAL (HOW IS IT FORMED)


Coal is a combustible black or brownish-black sedimentary rock normally occurring in rock strata in layers or veins called coal beds. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure. Coal is composed primarily of carbon along with variable quantities of other elements, chiefly hydrogen, with smaller quantities of sulfur, oxygen and nitrogen.


FORMATION OF COAL:-


Coal begins as layers of plant matter accumulating at the bottom of a body of water. For the process to continue, the plant matter must be protected from biodegradation and oxidization, usually by mud or acidic water. This traps their carbon in immense peat bogs that are eventually covered over and deeply buried by sediments. Under this compression the plant material is metamorphosed into coal. Over time, the chemical and physical properties of the plant remains are changed by geological action to create a solid material.
The wide shallow seas of the Carboniferous period provided ideal conditions for coal formation, although coal is known from most geological periods. The exception is the Coal gap in the Lower Triassic, where coal is rare. Coal is even known from Precambrian strata, which predate land plants. This coal is presumed to have originated from algal residues. Coal, a fossil fuel, is the largest source of energy for the generation of electricity worldwide, as well as one of the largest worldwide anthropogenic sources of carbon dioxide releases. Gross carbon dioxide emissions from coal usage are slightly more than those from petroleum and about double the amount from natural gas. Coal is extracted from the ground by mining, either underground by shaft mining through the seams or in open pits.




TYPES OF COAL:-

1. Peat, considered to be a precursor of coal, has industrial importance as a fuel in some regions, for example, Ireland and Finland. In its dehydrated form, peat is a highly effective absorbent for fuel and oil spills on land and water.
2. Lignite, also referred to as brown coal, is the lowest rank of coal and used almost exclusively as fuel for electric power generation. Jet is a compact form of lignite that is sometimes polished and has been used as an ornamental stone since the Upper Palaeolithic.

3. Sub-bituminous coal, whose properties range from those of lignite to those of bituminous coal are used primarily as fuel for steam-electric power generation. Additionally, it is an important source of light aromatic hydrocarbons for the chemical synthesis industry.
4. Bituminous coal, dense sedimentary rock, black but sometimes dark brown, often with well-defined bands of bright and dull material, used primarily as fuel in steam-electric power generation, with substantial quantities also used for heat and power applications in manufacturing and to make coke.
5. Steam coal is a grade between bituminous coal and anthracite, once widely used as a fuel for steam locomotives. In this specialized use it is sometimes known as sea-coal in the U.S. Small steam coal was used as a fuel for domestic water heating.
6. Anthracite(the highest rank):- A harder, glossy, black coal used primarily for residential and commercial space heating. It may be divided further into metamorphically altered bituminous coal and petrified oil as from the deposits in Pennsylvania.

7. Graphite, technically the highest rank but difficult to ignite and is not so commonly used as fuel. It is mostly used in pencils and when powdered as a lubricant.

       HUMAN SKELETON

The human skeleton consists of both fused and individual bones supported and supplemented by ligaments, tendons, muscles and cartilage. It serves as a scaffold which supports organs, anchors muscles and protects organs such as the brain, lungs and heart. The biggest bone in the body is the femur in the thigh and the smallest is the stapes bone in the middle ear. In an adult, the skeleton comprises around 30-40% of the total body weight and half of this weight is water.
Fused bones include those of the pelvis and the cranium. Not all bones are interconnected directly: there are three bones in each middle ear called the ossicles that articulate only with each other. The hyoid bone, which is located in the neck and serves as the point of attachment for the tongue, does not articulate with any other bones in the body, being supported by muscles and ligaments. Early in gestation, a fetus has a cartilaginous skeleton from which the long bones and most other bones gradually form throughout the remaining gestation period and for years after birth in a process called endochondral ossification. The flat bones of the skull and the clavicles are formed from connective tissue in a process known as intramembranous ossification and ossification of the mandible occurs in the fibrous membrane covering the outer surfaces of Meckel's cartilages. At birth, a newborn baby has over 300 bones, whereas on average an adult human has 206 bones. The difference comes from a number of small bones that fuse together during growth, such as the sacrum and coccyx of the vertebral column.

The axial skeleton is formed by the Vertebral column, the Rib cage and the skull. The axial skeleton transmits the weight from the head, the trunk and the upper extremities down to the lower extremities at the hip joints and is therefore responsible for the upright position of the human body. Most of the body weight is located in back of the spinal column which therefore have the erectors spinae muscles and a large amount of ligaments attached to it resulting in the curved shape of the spine. The 366 skeletal muscles acting on the axial skeleton position the spine, allowing for big movements in the thoracic cage for breathing and the head. Conclusive research cited by the American Society for Bone Mineral Research demonstrates that weight-bearing exercise stimulates bone growth. Only the parts of the skeleton that are directly affected by the exercise will benefit. Non weight-bearing activity including swimming and cycling has no effect on bone growth.

There are many differences between the male and female human skeletons. Most prominent is the difference in the pelvis owing to characteristics required for the processes of childbirth. The shape of a female pelvis is flatter more rounded and proportionally larger to allow the head of a fetus to pass. Also the coccyx of a female's pelvis is oriented more inferiorly whereas the man's coccyx is usually oriented more anteriorly. This difference allows more room for a developing fetus. Men tend to have slightly thicker and longer limbs and digit bones, while women tend to have narrower rib cages, smaller teeth, less angular mandibles, less pronounced cranial features such as the brow ridges and external occipital protuberance and the carrying angle of the forearm is more pronounced in females. Females also tend to have more rounded shoulder blades.

KILLER WAVES - TSUNAMI

A tsunami at one time referred to as a tidal wave, is a series of water waves caused by the displacement of a large volume of a body of water, usually an ocean, though it can occur in large lakes. Tsunamis are a frequent occurrence in Japan, approximately 195 events have been recorded. Owing to the immense volumes of water and the high energy involved, tsunamis can devastate coastal regions. Earthquakes, volcanic eruptions and other underwater explosions glacier calvings and other mass movements, meteorite ocean impacts or similar impact events, and other disturbances above or below water all have the potential to generate a tsunami.

Some meteorological conditions, such as deep depressions that cause tropical cyclones can generate a storm surge called a meteotsunami, which can raise tides several metres above normal levels. The displacement comes from low atmospheric pressure within the centre of the depression. As these storm surges reach shore, they may resemble tsunamis, inundating vast areas of land. Tsunami can be generated when the sea floor abruptly deforms and vertically displaces the overlying water. Tectonic earthquakes are a particular kind of earthquake that are associated with the Earth's crustal deformation. When these earthquakes occur beneath the sea, the water above the deformed area is displaced from its equilibrium position. More specifically, a tsunami can be generated when thrust faults associated with convergent or destructive plate boundaries move abruptly, resulting in water displacement, owing to the vertical component of movement involved. Movement on normal faults will also cause displacement of the seabed, but the size of the largest of such events is normally too small to give rise to a significant tsunami.Tsunamis have a small amplitude offshore and a very long wavelength ,which is why they generally pass unnoticed at sea, forming only a slight swell usually about 12 inches above the normal sea surface. They grow in height when they reach shallower water, in a wave shoaling process described below. A tsunami can occur in any tidal state and even at low tide can still inundate coastal areas. On April 1, 1946, a magnitude 7.8 earthquake occurred near the Aleutian Islands, Alaska. It generated a tsunami which inundated Hilo on the island of Hawai with a 14 metres high surge. The area where the earthquake occurred is where the Pacific Ocean floor is subducting under Alaska. Examples of tsunami originating at locations away from convergent boundaries include Storegga about 8,000 years ago, Grand Banks 1929, Papua New Guinea 1998. The Grand Banks and Papua New Guinea tsunamis came from earthquakes which destabilized sediments, causing them to flow into the ocean and generate a tsunami. They dissipated before traveling transoceanic distances.

The cause of the Storegga sediment failure is unknown. Possibilities include an overloading of the sediments, an earthquake or a release of gas hydrates like methane. The 1960 Valdivia earthquake 9.5, 1964 Alaska earthquake 9.2, 2004 Indian Ocean earthquake 9.2 and 2011 Tohoku earthquake 9.0 are recent examples of powerful megathrust earthquakes that generated tsunamis that can cross entire oceans. Smaller 4.2 earthquakes in Japan can trigger tsunamis that can only devastate nearby coasts but can do so in only a few minutes.

                                                                          TEACHER'S DAY  

Teachers Day is celebrated as a tribute to the valuable contribution made by teachers to the society by imparting knowledge and enlightening and shaping the career of students. Celebration of Teachers Day is fairly popular in many countries across the world and is even acknowledged by UNESCO. For students, Teachers Day is an occasion to pay reverence and gratitude to teachers for their selfless effort in shaping their career and enriching the education system in the process. When is Teachers’ Day celebrated? The date for celebrating this special event varies from country to country across the world. In India, Teachers Day is celebrated on the 5th of September every year, whereas, China celebrates this event on 10th September every year. The celebration in each country is generally correlated to either significant personalities or achievements of milestone in the field of education. India celebrates Teachers Day on September 5 since 1962 as it is the birth anniversary of Dr Sarvapalli Radhakrishnan, a prominent thinker, philosopher and an educator.

Most of the schools and institutions make elaborate preparations for the celebrations. The ceremony usually kicks off with a warm Teachers Day speech paying respect and thanking teachers for their contribution. This is often followed by a range of colourful cultural programs, feast and other activities which make the event special and memorable.  A few traditional ways of celebrating the event include presenting colourful flowers, beautiful Teachers Day cards or gifts to the teacher as tokens of love and admiration. But students often try innovative ways and ideas to celebrate Teachers Day. Some rely on creative and attractive Teachers Day greeting cards adorned with captivating and touchy quotes and messages to convey the indebtedness unfailingly and also to capture the wonderful moments of the event. Others select lovely and popular Teachers Day quotes to convey their inner feeling of love for their teacher.  Sending animated or e-greeting card is also a rage in the contemporary times. Available absolutely free of cost, these Teachers Day Greetings e-cards have become a preferred way to send warm wishes and shower emotions on teachers. Another modern and popular mode of wishing teachers today is the Teachers Day SMS. The advantage of sending SMS is that the message reaches its destination promptly and rarely goes unnoticed. For the celebration of Teachers Day, the text messages are available in varied languages allowing users to send SMS according to his/her preferred language.
All of us have been students at some stage of our life and have benefited from our teachers. Celebration of Teachers Day 2011 is a wonderful opportunity especially for all of us to show our gratitude and appreciation to our teachers.




Oh teacher, Oh teacher!


My test isn't signed
Because somehow

My parents went blind
Now, don't say it's my fault,
They left their hands in the bank vault.

Oh teacher, Oh teacher
Do you know why
I was born without wings
And so cannot fly
Thus I am late
Didn't have breakfast,
So if you don't mind,
Pass me a plate.

Oh teacher, Oh teacher!
I've failed again
Please don't scold me,
Now you'll see why,
I was thinking about
Having an eagle's brain.

            DAM


A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are often used in conjunction with dams to generate electricity. A dam can also be used to collect water or for storage of water which can be evenly distributed between locations.The word dam can be traced back to Middle English and before that, from Middle Dutch, as seen in the names of many old cities. Early dam building took place in Mesopotamia and the Middle East. Dams were used to control the water level, for Mesopotamia's weather affected the Tigris and Euphrates rivers, and could be quite unpredictable.

The earliest known dam is the Jawa Dam in Jordan, 100 kilometres northeast of the capital Amman. This gravity dam featured a 4.5 m high and 1 m wide stone wall, supported by a 50 m wide earth rampart. The structure is dated to 3000 BC. The Ancient Egyptian Sadd-el-Kafara Dam at Wadi Al-Garawi, located about 25 km south of Cairo, was 102 m long at its base and 87 m wide. The structure was built around 2800 or 2600 B.C. as a diversion dam for flood control, but was destroyed by heavy rain during construction or shortly afterwards. By the mid-late third century BC, an intricate water-management system within Dholavira in modern day India, was built. The system included 16 reservoirs, dams and various channels for collecting water and storing it.Roman dam construction was characterized by "the Romans' ability to plan and organize engineering construction on a grand scale". Roman planners introduced the then novel concept of large reservoir dams which could secure a permanent water supply for urban settlements also over the dry season. Their pioneering use of water-proof hydraulic mortar and particularly Roman concrete allowed for much larger dam structures than previously built, such as the Lake Homs Dam, possibly the largest water barrier to that date and the Harbaqa Dam both in Roman Syria. The highest Roman dam was the Subiaco Dam near Rome. Its record height of 50 m remained unsurpassed until its accidental destruction in 1305.

Roman engineers made routine use of ancient standard designs like embankment dams and masonry gravity dams. Apart from that, they displayed a high degree of inventiveness, introducing most of the other basic dam designs which had been unknown until then. These include arch-gravity dams, arch dams, buttress dams and multiple arch buttress dams, all of which were known and employed by the 2nd century AD. Roman workforces also were the first to build dam bridges, such as the Bridge of Valerian in Iran.
Eflatun Pınar is a Hittite dam and spring temple near Konya, Turkey. It's thought to be from the time of the Hittite empire between the 15th and 13 century BC.The Kallanai is constructed of unhewn stone, over 300 m long, 4.5 m high and 20 m wide, across the main stream of the Kaveri river in Tamil Nadu, South India. The basic structure dates to the 1st century AD. and is considered one of the oldest water-diversion or water-regulator structures in the world, which is still in use. The purpose of the dam was to divert the waters of the Kaveri across the fertile Delta region for irrigation via canals.It is considered to be the oldest dam still in use.
Du Jiang Yan is the oldest surviving irrigation system in China that included a dam that directed waterflow. It was finished in 251 B.C. A large earthen dam, made by the Prime Minister of Chu, Sunshu Ao, flooded a valley in modern-day northern Anhui province that created an enormous irrigation reservoir 100 km, a reservoir that is still present today.

In Iran, bridge dams such as the Band-e Kaisar were used to provide hydropower through water wheels, which often powered water-raising mechanisms. One of the first was the Roman-built dam bridge in Dezful, which could raise water 50 cubits in height for the water supply to all houses in the town. Also diversion dams were known. Milling dams were introduced which the Muslim engineers called the Pul-i-Bulaiti. The first was built at Shustar on the River Karun, Iran, and many of these were later built in other parts of the Islamic world. Water was conducted from the back of the dam through a large pipe to drive a water wheel and watermill. In the 10th century, Al-Muqaddasi described several dams in Persia. He reported that one in Ahwaz was more than 910 m long and that and it had many water-wheels raising the water into aqueducts through which it flowed into reservoirs of the city. Another one, the Band-i-Amir dam, provided irrigation for 300 villages.In the Netherlands, a low-lying country, dams were often applied to block rivers in order to regulate the water level and to prevent the sea from entering the marsh lands. Such dams often marked the beginning of a town or city because it was easy to cross the river at such a place, and often gave rise to the respective place names in Dutch.

For instance the Dutch capital Amsterdam started with a dam through the river Amstel in the late 12th century, and Rotterdam started with a dam through the river Rotte, a minor tributary of the Nieuwe Maas. The central square of Amsterdam, covering the original place of the 800 year old dam, still carries the name Dam Square or simply the Dam.French engineer Benoit Fourneyron developed the first successful water turbine in 1832. The era of large dams was initiated after Hoover Dam was completed on the Colorado River near Las Vegas in 1936. By 1997, there were an estimated 8,00000 dams worldwide, some 40,000 of them over 15 m high.

      REFRIGERATOR

A refrigerator referred to as a fridge is a common household appliance that consists of a thermally insulated compartment and a heat pump which transfers heat from the inside of the fridge to its external environment so that the inside of the fridge is cooled to a temperature below the ambient temperature of the room. Cooling is a popular food storage technique in developed countries and works by decreasing the reproduction rate of bacteria. The device is thus used to reduce the rate of spoilage of foodstuffs.
A refrigerator maintains a temperature a few degrees above the freezing point of water. Optimum temperature range for perishable food storage is 3 to 5 °C. A similar device which maintains a temperature below the freezing point of water is called a freezer.The refrigerator is a relatively modern invention among kitchen appliances. It replaced the icebox, which had been a common household appliance for almost a century and a half prior. For this reason, a refrigerator is sometimes referred to as an icebox.
refrigerators keep things cold because of the nature of heat. The Second Law of Thermodynamics essentially states that if a cold object is placed next to a hot object, the cold object will become warmer and the hot object will become cooler. A refrigerator does not cool items by lowering their original temperatures; instead, an evaporating gas called a refrigerant draws heat away, leaving the surrounding area much colder. Refrigerators and air conditioners both work on the principle of cooling through evaporation.

A refrigerator consists of two storage compartments - one for frozen items and the other for items requiring refrigeration but not freezing. These compartments are surrounded by a series of heat-exchanging pipes. Near the bottom of the refrigerator unit is a heavy metal device called a compressor. The compressor is powered by an electric motor. More heat-exchanging pipes are coiled behind the refrigerator. Running through the entire system is pure ammonia, which evaporates at -32 Celsius. This system is closed, which means nothing is lost or added while it is operating. Because liquid ammonia is a powerful chemical, a leaking refrigerator should be repaired or replaced immediately. The refrigeration process begins with the compressor. Ammonia gas is compressed until it becomes very hot from the increased pressure. This heated gas flows through the coils behind the refrigerator, which allow excess heat to be released into the surrounding air. This is why users sometimes feel warm air circulating around the fridge. Eventually the ammonia cools down to the point where it becomes a liquid. This liquid form of ammonia is then forced through a device called an expansion valve. Essentially, the expansion valve has such a small opening that the liquid ammonia is turned into a very cold, fast-moving mist, evaporating as it travels through the coils in the freezer. Since this evaporation occurs at -32 degrees Celsius, the ammonia draws heat from the surrounding area. This is the Second Law of Thermodynamics in effect. Cold material, such as the evaporating ammonia gas, tend to take heat from warmer materials, such as the water in the ice cube tray.

As the evaporating ammonia gas absorbs more heat, its temperature rises. The cool ammonia still draws heat from the warmer objects in the fridge, but not as much as the freezer section. The ammonia gas is drawn back into the compressor, where the entire cycle of pressurization, cooling and evaporation begins.