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Binary Linear Congruence Code
Published in Khodakhast Bibak, Restricted Congruences in Computing, 2020
Deletions or insertions can occur in many systems; for example, they can occur in some communication and storage channels and in biological sequences. A deletion or insertion in a DNA sequence leads to a genetic mutation known as the frameshift mutation. Therefore, studying deletion/insertion correcting codes may lead to important insight into genetic processes and into many communication problems. Deletion correcting codes have been the subject of intense research for more than fifty years [139; 144; 181], with recent results settling long-standing open problems regarding constructions of multiple deletion correcting codes with low redundancy [34; 37]. Nevertheless, our understanding about these codes and channels with this type of error is still very limited, and many open problems in the area remain, especially when considering constructions of deletion correcting codes that satisfy additional constraints, such as weight or parity constraints. Examples include codes in the Damerau distance [67], based on single deletion correcting codes with even weight, and Shifted Varshamov–Tenengolts codes [172] used for burst deletion correction. In such settings, one important question is to determine the weight enumerators of the component deletion correcting codes in order to estimate the size [47; 111] of the weight-constrained deletion correcting codes. The component deletion correcting code is frequently defined in terms of a linear congruence for which the number of solutions of some fixed weight determines the size of the constrained code.
The application of search methods for solving optimization problems
Published in Vladimir Litvinenko, Topical Issues of Rational Use of Natural Resources 2019, 2019
Consider the most primitive form of natural selection. the target function depends on several parameters. Each parameter «mutates» (changes) in one direction or another. «Mutations» can be useful or harmful. Out of every n «mutants» the best combination is chosen from the point of view of the objective function, for example, [vv]=min. Other combinations are rejected (eliminated). These steps are repeated until the result is satisfactory.
Environmental Disease
Published in Gary S. Moore, Kathleen A. Bell, Living with the Earth, 2018
Gary S. Moore, Kathleen A. Bell
Many human diseases are associated with genetic defects. These defects can occur as (1) single-gene defects known as a point mutations or base substitutions or (2) cytogenetic defects in which there are abnormalities in the number or structure of chromosomes. A point mutation occurs when a single nucleotide base is replaced at one point in the DNA molecule with a different base. The DNA replicates with a substituted base pair such that A:T might be substituted for C:G. This base substitution could result in the incorporation of an incorrect amino acid into a synthesized protein, thereby rendering the protein less active or inactive. The resulting effect may be imperceptible or neutral or may result in one of many serious human ailments such as cystic fibrosis (CF), phenylketonuria (PKU), hereditary spherocytosis, alpha-1-antitrypsin deficiency, Gaucher’s disease, achondroplastic dwarfism, hemophilia, or certain forms of diabetes (Figure 4.5). Point mutations may occur spontaneously because of occasional mistakes in the process of DNA replication, without any intervention of external factors. There are also agents in the environment including chemicals or radiation that promote or cause such mutations. These agents are called mutagens. When such mutations occur, they become part of all the daughter cells of that cell. If the mutations occur in the cells that lead to reproductive cells, these defective genes may be inherited just as are healthy genes.
Evolutionary computation for bottom-up hypothesis generation on emotion and communication
Published in Connection Science, 2021
Casper Hesp, Bram T. Heerebout, R. Hans Phaf
Because differential frequencies only emerged in a single agent, the chances that they could be exapted reliably into a communicative function would be rather slim when starting from scratch as in Simulation 1. In nature, genetic stability can be enhanced by mechanisms that limit the proliferation of spontaneous mutations (cf, Drake et al., 1998). If a specific gene is beneficial but very vulnerable to mutations, the advantage can be maintained through new mutations that reduce the overall mutation rate. Similarly, the mutation size could be coded into the agents’ genes here, so that evolutionary selection can act on the mutation size. This would markedly increase the search space of the genetic algorithm however and would go beyond the scope of the current study. Therefore, to limit the search space in Simulation 2, we started with the most successful genetic configuration in the initial agents (i.e. the highest fitness agent from Simulation 1), while reducing the average overall mutation size.
Path planning for minimally-invasive knee surgery using a hybrid optimization procedure
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2018
Adam Ciszkiewicz, Grzegorz Milewski
RC-GA is a variation of Genetic Algorithm (Goldberg 1989), which operates on real-valued decision variables. It is well suited for problems with a continuous domain, such as path planning (Herrera et al. 1998). The algorithm works by iteratively improving a set of solutions, which is referred to as population. The initial population is generated randomly. To create a new children population from the previous one, three genetic operators are used: the selection, crossover and mutation. The selection procedure selects parents from the previous population based on the objective function values. The crossover function defines how to obtain crossover-children from parents. Also, some parents undergo mutation and create mutation-children. The children population is then rated and the process is repeated until the stop criterion is met. RC-GA was implemented using roulette wheel selection (Baker 1987) with nonlinear rank-based fitness scaling, BLX-α crossover with α = 0.5 (Eshelman and Schaffer 1993) and nonuniform mutation (Michalewicz 1992). The number of generations was set to 150, while the population size was 60. The crossover ratio was 0.80 and the elite count was at 5.00% of population size.
Breast Cancer Detection by Terahertz UWB Microstrip Patch Antenna Loaded with 6X6 SRR Array
Published in IETE Journal of Research, 2023
Kritika Singh, Marshal Dhayal, Smrity Dwivedi
Cancer is one of the leading causes of the increasing mortality rate worldwide. It occurs when cells become anomalous and grow out of control. Normal cells in the body divide, proliferate and die in response to specific cues. Whereas, cancer cells ignore these signals and continue to proliferate. Additionally, cancer cells may develop a tumor at the initial site before spreading and forming additional tumors elsewhere. Tumors are classified based on non-cancerous and cancerous, i.e. Benign (Non-Cancerous), which remains in one place, and Malignant (Cancerous), which spreads. Malignant tumor cells break off and spread throughout the whole body and start forming tumors in other body regions. This process is called metastasis; the cancer stage is known as metastatic, the most dangerous stage. Cancer cells can begin to develop when DNA based genes undergo specific alterations or mutations that induce aberrant cell behaviour. These abnormalities may result from external factors such as nicotine and UV radiation. The mutations could be inherited or entirely random. Cancer has four stages shown in Table 1 [1]. According to the recent data over 2.3 million new cases and 685,000 deaths in 2020 and it is predicted to increase to over 3 million new cases and 1 million deaths in 2040. Due to population growth, it is anticipated that by 2040 there will be approximately 3 million new cases of breast cancer and 1 million fatalities annually [2]. The World Health Organization (WHO) says that more than half of the world's people can't get diagnostic imaging [3]. Cancer is only curable only when detected at an early stage.