Binary chromosomes

For the selection of descriptors, GA simulated evolution of a population. Each individual of the population represents a subset of descriptors and is defined by a chromosome of binary values. The chromosome has as many genes as there are possible descriptors (92 for the aromatic group, 119 for non-rigid aliphatic,... 

The majority of bacteria reproduce-by simple binary fission the circular chromosome divides into two identical circles which segregate at opposite ends ofthe cell. At the same time, the cell wall is laid down in the middle ofthe cell, which finally grows to produce two new cells each with its own wall and nucleus. Each ofthe two new cells will be an exact copy of the original cell from which they arose and no new genetic material is received and none lost. 

Since the genomes representing the DP are no more than four binary strings, it is possible to use a GA to search for a set of four chromosomes (a genome) for a DP, instead of handcrafting the chromosomes as had been done so far. 

A block diagram of our pattern recognition GA is shown in Fig. 3. Selected feature subsets are coded as binary strings called chromosomes. Each chromosome describes a unique set of features. A particular feature is present in a chromosome or binary string if the corresponding bit in the string is set to 1. The length of each chromosome is equal to the number of features in the data... 

A population is made of a series of chromosomes. Each chromosome is a binary vector, where each position (a gene) corresponds to a variable (i.e. a chromosome represents a model made up of a subset of... 

An object in a binary image (two grey level) consists of a string which has n consecutive ones separated from other groups of ones by at least n zeros on either side. The parameter, n, is chosen as the optimal choice between the width of a chromosome and the spacing between two chromosomes in a metaphase cell under this magnification. Thus, for example, the string... 

One of those components, plasmids, are small, extrachromosomal genetic structures carried by many strains of bacteria. Like the chromosome, plasmids are made of a circular piece of DNA. Unlike the chromosome, they are not involved in reproduction. Only the chromosome has the genetic instructions for initiating and carrying out cell division, or binary fission, the primary means of reproduction in bacteria. Plasmids replicate independently of the chromosome and, while not essential for survival, appear to give bacteria a selective advantage. 

We used a standard binary GA whose detail can be formd in various textbooks on GA. We describe only the step of coding from true values of decision variables into binary variables in the chromosome as follows ... 

The problem feasibility check starts by enumerating all the sensors that can be placed in the plant. A binary gene is created for each sensor its value is set to 1 when the sensor is selected and 0 otherwise. The set of genes forms a chromosome whose length is equal to the number of possible sensors. It may appear that a variable is measured by more than one sensor so that the precision of the most accurate one is taken into account for the bounds calculation. The residual bounds and the residuals are estimated for the initial sensor network indeed, a noise bounded by the accuracy of the sensor is added to each variable for each measurement time before the mean of the variables and the residuals are calculated. The noise on the variables and then their values depend thus of the sensor network as well as the residual bounds. 

Plasmids replicate independently of the chromosome within the cell, so that both daughter cells contain a copy of the plasmid after binary fission. Plasmids may also be passed from one cell to another by various means (Chapter 3). Some plasmids exhibit a marked degree of host specificity and... 

J. A. Cuticchia, J. Arnold, W.E. Timberlake, The use of simulated annealing in chromosome reconstruction experiments based on binary scoring. Genetics, 132 (1992) 591. 

Bacteria Simple, single chromosome (prokaryote), usually single-celled organisms, 1-6 p,m diameter, spherical (coccus), or rod-like (bacillus) in shape Asexually, by binary fission (simple cell division) Air, water, and soil (sour milk, cheeses, yogurt, sauerkraut)... 

More recently, another adaptation of jumping genes, NSGA-II-aJG, has been developed by Bhat et al. (2006) and Bhat (2007). In this fixed-length (fb binaries) JG adaptation, a probability, Pjg, is used to see if a chromosome is to be modified. If yes, a single site only is identified (randomly) in it, from location 1 to n hr - fb- The other end of the JG is selected/i, binaries beyond it. The sub-string of binaries in-between these... 

The user specified probability, Psjg, of carrying out the sJG operation on a chromosome is used to find out if this operation is to be carried out on a chromosome. If this operation is to be performed, a random number is generated and converted into an integral value, a, lying between I and n. All the lstring,a lstring,a may or may not be equal for different decision variables) binaries of the a decision variable are replaced by new,... 

Serra, J.R., Thompson, E.D. and Jurs, P.C. (2003) Development of binary classification of structural chromosome aberrations for a diverse set of organic compounds from molecular structure. Chem. Res. Toxicol., 16, 153—163. 

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