Search results for "Genetic algorithm"
showing 10 items of 834 documents
A computer program suitable for analysis of choice of categories in biomedical data recognition problems.
1980
The optimum choice of categories in problems of medical data recognition is governed by the choice of categories, the selection of appropriate features, and by the choice of a loss function. Under these circumstances it is often difficult to find out the suitable classification scheme. The computer program described here serves for the design of the optimum recognition procedure. The Bayes rule is used as decision rule. A criterion for the comparison of different choice of categories is given. The program can be performed after estimation of the underlying prior probabilities and the conditional densities obtained from a training set, and before testing the decision rule with real data.
An Optimized Design of Choice Experiments: A New Approach for Studying Decision Behavior in Choice Task Experiments
2014
In this paper, we present a new approach for the optimal experimental design problem of generating diagnostic choice tasks, where the respondent's decision strategy can be unambiguously deduced from the observed choice. In this new approach, we applied a genetic algorithm that creates a one-to-one correspondence between a set of predefined decision strategies and the alternatives of the choice task; it also manipulates the characteristics of the choice tasks. In addition, this new approach takes into account the measurement errors that can occur when the preferences of the decision makers are being measured. The proposed genetic algorithm is capable of generating diagnostic choice tasks eve…
A complementary mobile phase approach based on the peak count concept oriented to the full resolution of complex mixtures
2011
Situations of minimal resolution are often found in liquid chromatography, when samples that contain a large number of compounds, or highly similar in terms of structure and/or polarity, are analysed. This makes full resolution with a single separation condition (e.g., mobile phase, gradient or column) unfeasible. In this work, the optimisation of the resolution of such samples in reversed-phase liquid chromatography is approached using two or more isocratic mobile phases with a complementary resolution behaviour (complementary mobile phases, CMPs). Each mobile phase is dedicated to the separation of a group of compounds. The CMPs are selected in such a way that, when the separation is cons…
Solvent selection in liquid chromatography
2017
Many solvents and additives are used to prepare mobile phases in liquid chromatography (LC). Also, mixtures of solvents at different ratios are used to modify the mobile-phase properties. This can make solvent selection for method development a puzzling task, unless suitable guidelines are followed. This chapter summarizes the most common strategies used by skilled chromatographers in reversed-phase, normal-phase, and hydrophilic interaction LC. These are based on considerations about the global polarity of solutes, stationary phase, and mobile phase, which determine the elution strength, and on the particular profile of the contributions of intermolecular interactions to the global polarit…
Identification of Key Gin Aroma Compounds
2014
Potential impact aroma compounds of gin have been identified using Gas Chromatogry Olfactometry Mass-Spectrometry (GC-O-MS). In order to select some of them for a recombination study, we developed a specific procedure. Instead of only choosing the compounds on criteria such as their odor quality or their odor activity values, we also used physico-chemical parameters and information on their botanical origin. Data were organized in blocks homogeneous in terms of parameter type. Different statistical treatments were used in order to classify the compounds either by analyzing the parameters altogether or separately block by block.
Analytical methodologies for chromium speciation in solid matrices: a survey of literature
1998
The analytical literature about chromium speciation in solid samples has been surveyed. From 451 articles published on the speciation of chromium from 1983 to 1997, the methodologies to do speciation in solids after sample pretreatment are discussed, through consideration of the types of samples and their dissolution, the analytical techniques employed for chromium measurement, and the figures of merit of the 86 papers reported in the Analytical Abstracts data base.
Chromium speciation in liquid matrices: a survey of the literature
2000
A thorough review of the literature published (1983 - March 1999) on chromium speciation in liquid samples is presented, and analytical techniques used in the 404 articles are summarized. The discussion focuses on atomic spectrometric techniques, which are mainly employed for chromium speciation in liquid matrices (134 articles). Details on the type of pretreatment, species, samples, techniques and analytical features of the methodologies proposed are given.
The DrosDel Deletion Collection: A Drosophila Genomewide Chromosomal Deficiency Resource
2007
AbstractWe describe a second-generation deficiency kit for Drosophila melanogaster composed of molecularly mapped deletions on an isogenic background, covering ∼77% of the Release 5.1 genome. Using a previously reported collection of FRT-bearing P-element insertions, we have generated 655 new deletions and verified a set of 209 deletion-bearing fly stocks. In addition to deletions, we demonstrate how the P elements may also be used to generate a set of custom inversions and duplications, particularly useful for balancing difficult regions of the genome carrying haplo-insufficient loci. We describe a simple computational resource that facilitates selection of appropriate elements for generat…
One-Sided Prototype Selection on Class Imbalanced Dissimilarity Matrices
2012
In the dissimilarity representation paradigm, several prototype selection methods have been used to cope with the topic of how to select a small representation set for generating a low-dimensional dissimilarity space. In addition, these methods have also been used to reduce the size of the dissimilarity matrix. However, these approaches assume a relatively balanced class distribution, which is grossly violated in many real-life problems. Often, the ratios of prior probabilities between classes are extremely skewed. In this paper, we study the use of renowned prototype selection methods adapted to the case of learning from an imbalanced dissimilarity matrix. More specifically, we propose the…