Rocco Francis Marchegiano, better known as Rocky Marciano (September 1, 1923 – August 31, 1969), was an American boxer. Marciano was the World Heavyweight Boxing Champion from 9/23/1952 until 11/30/1956. He had the shortest reach of any heavyweight champion at only 68 inches (173 cm). He was also short for a champion, standing 5'11" (180.3 cm). Marciano is the only heavyweight champion in professional boxing history who never lost or drew (tied) in a professional match. He won 43 fights by a way of knockout or technical knockout, an 87.76% knockout rate.
His parents were Italian immigrants.
Before becoming a professional fighter, Marciano had an amateur record of 11-3. Marciano's first professional fight was in March 1947. He won the championship from Jersey Joe Walcott on September 23, 1952.
Marciano was named fighter of the year by Ring Magazine three times. His three championship fights between 1952-54 were named fights of the year by that magazine. Marciano's last title fight was against Archie Moore on September 21, 1955. Marciano was knocked down in the fight, but he got up and knocked out Moore in the 9th round. Marciano announced his retirement in a press conference on April 27, 1956.
Marciano considered a comeback in 1959 when Ingemar Johansson won the heavyweight championship from Floyd Patterson on June 26, 1959. However, Floyd Patterson's contract demanded a rematch with Ingemar within one year. After a period in training and thinking about a comeback, Marciano decided against it and never seriously considered a comeback again.
In 1969, on the eve of his 46th birthday, Marciano was a passenger in a small private plane, a Cessna 172, headed to Des Moines, Iowa. It was at night and bad weather set in. The pilot tried to land the plane on a small airfield outside Newton, Iowa, but the plane hit a tree two miles short of the runway. The passengers died almost instantly. He is entombed in a crypt at Forest Lawn Memorial Cemetery in Fort Lauderdale, Florida. His widow, who died exactly five years after him at the age of 46, is entombed next to him.
Exponentiation by squaring
Exponentiating by squaring is an algorithm. It is used for quickly working out large integer powers of a number. It is also known as the square-and-multiply algorithm or binary exponentiation. It uses the binary expansion of the exponent. It is of quite general use, for example in modular arithmetic.
The algorithm is believed to have first been documented in the Sanskrit book "Chandah-sûtra", about 200 BC.
The following recursive algorithm computes "x" for a positive integer "n" where n > 0:
This algorithm is much faster than the ordinary method to compute such a value. Multiplying x by itself, n operations are needed to calculate "x ". With the method shown above, only log2(n) operations are needed.
Smart card
A smart card is a card with a microchip in it. Such cards are used as a method of identification and authentication.
Plastic cards that allow to take out money from a automated teller machine (ATM) often are smart cards nowadays (Some of them still have a magnetic stripe which holds the same information). Very often the user is identified with a PIN. If the PIN is entered correctly, money can be withdrawn. If the PIN is not entered correctly, the card is blocked (after a number of false attempts).
At first, smart cards were used in public telephones in France, in 1983. There, the card simply stored a pre-paid credit. This credit was reduced when calls were made. Another way to solve the problem is that the balance is stored in a remote database. To make calls, a (usually toll-free number) is first called. From there, additional calls can be made. This eliminates the need for cards with chips on them.
Smart cards also have many other uses, such as for making payments. These kinds of cards are used a lot in Japan, Singapore, and the Octopus card in Hong Kong.
There are two basic kinds of smart cards:
Both kind of cards contain a controller for managing the I/O.
Many smart cards have RFID technology that allows them to be used without inserting them into a machine. They just need to be placed on a reader. These are called "contactless smart cards" and many credit and debit cards in the 21st century are this kind.
Coprime
In mathematics, two integers ("a" and "b") are co-prime (or relatively prime) if they share no common factors. This is sometimes written as formula_1. In other words, there is no number, other than 1, that divides both a and b evenly. In which case, the greatest common divisor (GCD, or highest common factor) of these numbers is 1.
As an example, 6 and 35 are coprime, because the factors of 6, 2 and 3, do not divide 35 evenly. On the other hand, 6 and 27 are not coprime, because 3 divides both 6 and 27. Another example is 4 and 5:
4 = 2*2*1;
5 = 5*1 (Prime). The only common factor is 1, so they are coprime.
On the other hand, 10 and 5:
10 = 5*2
5 = 5*1 (Prime). The common factors are 5 and 1, so they are not coprime.
Prime numbers are always coprime to each other.
Euler's totient function
In number theory, the totient of a positive integer "n" is the number of positive integers smaller than "n" which are coprime to "n" (they share no factors except 1). It is often written as formula_1.
For example, formula_2, because there are four numbers (1, 3, 5 and 7) which do not share any factors with 8.
The function formula_3 used here is the totient function, usually called the Euler totient or Euler's totient, after the Swiss mathematician Leonhard Euler, who studied it.
The totient function is also called Euler's phi function or simply the phi function, since the Greek letter Phi (formula_3) is so commonly used for it. The cototient of "n" is defined as formula_5.
The totient function is important mainly because it gives the size of the multiplicative group of integers modulo "n". More precisely, formula_6 is the order of the group of units of the ring formula_7. This fact, together with Lagrange's theorem, provides a proof for Euler's theorem.
A common use of the totient function is in the RSA algorithm. The RSA algorithm is a popular method of encryption used worldwide.
For any prime number, "p", formula_8.
Key (cryptography)
In cryptography, a key (or cryptographic key) is a piece of information that allows control over the encryption or decryption process.
There are two basic types of cryptographic algorithms.
For symmetric algorithms, a minimum key size of 128 bits is recommended. For applications that need extreme security, such as top secret documents, 256 bits is recommended. Many older ciphers used 40, 56, or 64-bit keys—these have all been cracked by brute force attack because the key was too short.
Asymmetric (public key) algorithms need much longer keys to be secure. For RSA, at least 2048 bits is recommended. The largest publicly-known key that has been cracked was a 768-bit key.
Hollywood, Florida
Hollywood is a city in Broward County in Florida in the United States. In 2005 there were 145,629 people living in Hollywood, based on United States Census Bureau figures.
Echo
Echo could mean:
Magnetic stripe card
A Magnetic stripe card is a plastic card which has a magnetic stripe on it. Different kinds of information can be stored on the magnetic stripe. Such stripes are usually made of small particles of iron (or another metal). Information is stored by changing the magnetism of the particles, as with magnetic tape
Today such cards are widely used for:
There are different ways in which the data is stored on the card. But all of them are read in much the same way, by "swiping" (sliding the card through a slot) on a machine called a reader. These readers can be separate from or built into other machines such as a payment terminal in a cash register or point of sale system.
Similar cards, which can also do calculations themselves, are called smart cards.