Token

Token may refer to:

Currency

Computing

Token Racing

Token Racing was a short-lived Formula One team and constructor from the United Kingdom, participating in four Grands Prix of the 1974 Formula One season.

Token's history began in late 1973 when Rondel Racing, the successful Formula Two team founded by Ron Dennis and Neil Trundle, decided to enter F1. Dennis asked Ray Jessop to design the car, while backing was to come from the French oil company Motul, which had sponsored the team for the previous two years. But when the 1973 oil crisis hit, Motul withdrew, and Dennis was forced to close down the team. The F1 project was subsequently sold to shipbroker Tony Vlassopulo and Lloyd's underwriter Ken Grob, from whose first names the "Token" name was derived, while the car was called the RJ02 in honour of Jessop.

The team made its F1 debut in April 1974 at the non-Championship International Trophy race at Silverstone, with Welshman Tom Pryce at the wheel. Its first Championship race came the following month, at the Belgian Grand Prix, where Pryce qualified 20th but retired at three-quarter distance following a collision with Jody Scheckter's Tyrrell. The team entered the next race at Monaco but was forbidden from taking part on the basis of Pryce's supposed inexperience, prompting the Welshman to move to the Shadow team.

Token (railway signalling)

In railway signalling, a token is a physical object which a locomotive driver is required to have or see before entering onto a particular section of single track. The token is clearly endorsed with the name of the section it belongs to. A token system is used for single lines because of the very much greater risk of serious collision in the event of irregular working by signalmen or traincrews, than on double lines.

Principle

The operation of a bidirectional single track line has obvious problems, the most serious of which is the possibility of two trains traversing the line travelling towards each other, each driver unaware that the other is using the line. The simplest method of controlling such a line is to have only one engine operational, on the basis that a single train cannot collide with itself, and in the absence of another engine, there is nothing else for it to collide with. Such a system is known as "one engine in steam". Such schemes were used, and indeed still are used on some branches of rail networks, and on heritage railways. The main problem with such a scheme is that it is best suited to a completely isolated branch of single track line. Where the section has to be integrated into a larger railway system, it becomes exceptionally limiting in the level of operations that it allows, and the opportunity for a mistake to be made, and an ensuing accident to occur, is high.

Fitness

Fitness may refer to:

See also

Fitness function

A fitness function is a particular type of objective function that is used to summarise, as a single figure of merit, how close a given design solution is to achieving the set aims.

In particular, in the fields of genetic programming and genetic algorithms, each design solution is commonly represented as a string of numbers (referred to as a chromosome). After each round of testing, or simulation, the idea is to delete the 'n' worst design solutions, and to breed 'n' new ones from the best design solutions. Each design solution, therefore, needs to be awarded a figure of merit, to indicate how close it came to meeting the overall specification, and this is generated by applying the fitness function to the test, or simulation, results obtained from that solution.

The reason that genetic algorithms cannot be considered to be a lazy way of performing design work is precisely because of the effort involved in designing a workable fitness function. Even though it is no longer the human designer, but the computer, that comes up with the final design, it is the human designer who has to design the fitness function. If this is designed badly, the algorithm will either converge on an inappropriate solution, or will have difficulty converging at all.

Fitness (magazine)

Fitness is a United States-based women's magazine, focusing on health, exercise, and nutrition. It is owned and published by the Meredith Corporation. The editor-in-chief of Fitness is Betty Wong.

History

Fitness was launched in 1992, and was acquired by the Meredith Corporation from Bertelsmann's Gruner + Jahr in 2005. In 2005, Fitness also launched its web presence, giving readers separate online resources for fitness and health tips alongside the magazine's monthly editorial content. Betty Wong became Editor-in-Chief in September 2008, incorporating several changes to the magazine, creating several new columns and features. In 2009, Fitness posted significant ad page gains according to the Publishers Information Bureau, increasing by 18.4% when overall magazine publishers' counts were down 27.9% industry-wide. It was recognized for several awards, having been awarded "Most Improved Publication" and best "How-To/Instructional" feature in minOnline's Editorial and Design Awards.