Sunday, 27 July 2014

Global Fitness Fitness Exercise for Women for Men for Women at Home for Men at Home Abs For Kids for Women to Lose Weight Tumblr Photos 

Global Fitness Biography

Source:- Google.com.pk
 Global fitness is a general state of health and well-being or specifically the ability to perform aspects of sports or occupations. Physical fitness is generally achieved through correct nutrition, exercise, hygiene and rest. It is a set of attributes or characteristics that people have or achieve that relates to the ability to perform physical activity.
Before the industrial revolution, fitness was the capacity to carry out the day’s activities without undue fatigue. However with automation and changes in lifestyles physical fitness is now considered a measure of the body’s ability to function efficiently and effectively in work and leisure activities, to be healthy, to resist hypokinetic diseases, and to meet emergency situationsFitness (often denoted w in population genetics models) is a central idea in evolutionary theory. It can be defined either with respect to a genotype or to a phenotype in a given environment. In either case, it describes the ability to both survive and reproduce, and is equal to the average contribution to the gene pool of the next generation that is made by an average individual of the specified genotype or phenotype. The term "Darwinian fitness" is often used to make clear the distinction with physical fitness.[1] If differences between alleles of a given gene affect Darwinian fitness, then the frequencies of the alleles will change across generations; the alleles with higher fitness become more common. This process is called natural selection.
An individual's fitness is manifested through its phenotype. The phenotype is affected by the developmental environment as well as by genes, and the fitness of a given phenotype can be different in different environments. The fitnesses of different individuals with the same genotype are therefore not necessarily equal. However, since the fitness of the genotype is an averaged quantity, it will reflect the reproductive outcomes of all individuals with that genotype in a given environment or set of environments.
Inclusive fitness differs from individual fitness by including the ability of an allele in one individual to promote the survival and/or reproduction of other individuals that share that allele, in preference to individuals with a different allele. One mechanism of inclusive fitness is kin selection.
In many real-world optimization problems including engineering problems, the number of fitness function evaluations needed to obtain a good solution dominates the optimization cost. In order to obtain efficient optimization algorithms, it is crucial to use prior information gained during the optimization process. Conceptually, a natural approach to utilizing the known prior information is building a model of the fitness function to assist in the selection of candidate solutions for evaluation. A variety of techniques for constructing of such a model, often also referred to as surrogates, metamodels or approximation models – for computationally expensive optimization problems have been considered.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 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.

Moreover, the fitness function must not only correlate closely with the designer's goal, it must also be computed quickly. Speed of execution is very important, as a typical genetic algorithm must be iterated many times in order to produce a usable result for a non-trivial problem.

Fitness approximation may be appropriate, especially in the following cases:

Fitness computation time of a single solution is extremely high
Precise model for fitness computation is missing
The fitness function is uncertain or noisy.
Two main classes of fitness functions exist: one where the fitness function does not change, as in optimizing a fixed function or testing with a fixed set of test cases; and one where the fitness function is mutable, as in niche differentiation or co-evolving the set of test cases.
 Another way of looking at fitness functions is in terms of a fitness landscape, which shows the fitness for each possible chromosome.
 Definition of the fitness function is not straightforward in many cases and often is performed iteratively if the fittest solutions produced by GA are not what is desired. In some cases, it is very hard or impossible to come up even with a guess of what fitness function definition might be. Interactive genetic algorithms address this difficulty by outsourcing evaluation to external agents (normally humans).
 Global Fitness Fitness Exercise for Women for Men for Women at Home for Men at Home Abs For Kids for Women to Lose Weight Tumblr Photos
Global Fitness Fitness Exercise for Women for Men for Women at Home for Men at Home Abs For Kids for Women to Lose Weight Tumblr Photos
Global Fitness Fitness Exercise for Women for Men for Women at Home for Men at Home Abs For Kids for Women to Lose Weight Tumblr Photos
Global Fitness Fitness Exercise for Women for Men for Women at Home for Men at Home Abs For Kids for Women to Lose Weight Tumblr Photos
Global Fitness Fitness Exercise for Women for Men for Women at Home for Men at Home Abs For Kids for Women to Lose Weight Tumblr Photos
 Global Fitness Fitness Exercise for Women for Men for Women at Home for Men at Home Abs For Kids for Women to Lose Weight Tumblr Photos
 Global Fitness Fitness Exercise for Women for Men for Women at Home for Men at Home Abs For Kids for Women to Lose Weight Tumblr Photos
Global Fitness Fitness Exercise for Women for Men for Women at Home for Men at Home Abs For Kids for Women to Lose Weight Tumblr Photos
Global Fitness Fitness Exercise for Women for Men for Women at Home for Men at Home Abs For Kids for Women to Lose Weight Tumblr Photos
Global Fitness Fitness Exercise for Women for Men for Women at Home for Men at Home Abs For Kids for Women to Lose Weight Tumblr Photos
 Global Fitness Fitness Exercise for Women for Men for Women at Home for Men at Home Abs For Kids for Women to Lose Weight Tumblr Photos 

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