1,419 research outputs found
Denoising Autoencoders for fast Combinatorial Black Box Optimization
Estimation of Distribution Algorithms (EDAs) require flexible probability
models that can be efficiently learned and sampled. Autoencoders (AE) are
generative stochastic networks with these desired properties. We integrate a
special type of AE, the Denoising Autoencoder (DAE), into an EDA and evaluate
the performance of DAE-EDA on several combinatorial optimization problems with
a single objective. We asses the number of fitness evaluations as well as the
required CPU times. We compare the results to the performance to the Bayesian
Optimization Algorithm (BOA) and RBM-EDA, another EDA which is based on a
generative neural network which has proven competitive with BOA. For the
considered problem instances, DAE-EDA is considerably faster than BOA and
RBM-EDA, sometimes by orders of magnitude. The number of fitness evaluations is
higher than for BOA, but competitive with RBM-EDA. These results show that DAEs
can be useful tools for problems with low but non-negligible fitness evaluation
costs.Comment: corrected typos and small inconsistencie
Use of genetic algorithms with multivariate regression for determination of gelatine in historic papers based on FT-IR and NIR spectral data
Quantitative non-destructive analysis of individual constituents of historic rag paper is crucial for its effective preservation. In this work, we examine the potentials of mid- and near-infrared spectroscopy, however, in order to fully utilise the selectivity inherent to spectroscopic multivariate measurements, genetic algorithms were used to select spectral data derived from information-rich FT-IR or UV-vis-NIR measurements to build multivariate calibration models based on partial least squares regression, relating spectra to gelatine content in paper. A selective but laborious chromatographic method for the quantification of hydroxyproline (HYP) has been developed to provide the reference data on gelatine content. We used 9-fluorenylmethyl chloroformate (FMOC) to derivatise HYP, which was subsequently determined using reverse-phase liquid chromatographic separation and fluorimetric detection. In this process, the sample is consumed, which is why the method can only be used as a reference method.The sampling flexibility afforded by small-size field-portable spectroscopic instrumentation combined with chemometric data analysis, represents an attractive addition to existing analytical techniques for cultural heritage materials. (C) 2010 Elsevier B.V. All rights reserved
An analysis of the local optima storage capacity of Hopfield network based fitness function models
A Hopfield Neural Network (HNN) with a new weight update rule can be treated as a second order Estimation of Distribution Algorithm (EDA) or Fitness Function Model (FFM) for solving optimisation problems. The HNN models promising solutions and has a capacity for storing a certain number of local optima as low energy attractors. Solutions are generated by sampling the patterns stored in the attractors. The number of attractors a network can store (its capacity) has an impact on solution diversity and, consequently solution quality. This paper introduces two new HNN learning rules and presents the Hopfield EDA (HEDA), which learns weight values from samples of the fitness function. It investigates the attractor storage capacity of the HEDA and shows it to be equal to that known in the literature for a standard HNN. The relationship between HEDA capacity and linkage order is also investigated
A Study on Multimemetic Estimation of Distribution Algorithms
PPSN 2014, LNCS 8672, pp. 322-331Multimemetic algorithms (MMAs) are memetic algorithms in which memes (interpreted as non-genetic expressions of problem solving
strategies) are explicitly represented and evolved alongside genotypes. This process is commonly approached using the standard genetic
procedures of recombination and mutation to manipulate directly information at the memetic level. We consider an alternative approach
based on the use of estimation of distribution algorithms to carry on this self-adaptive memetic optimization process. We study the application of
different EDAs to this end, and provide an extensive experimental evaluation. It is shown that elitism is essential to achieve top performance, and that elitist versions of multimemetic EDAs using bivariate probabilistic
models are capable of outperforming genetic MMAs.This work is partially supported by MICINN project
ANYSELF (TIN2011-28627-C04-01), by Junta de Andalucía project DNEMESIS (P10-TIC-6083) and by Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tech
Stochastic stability versus localization in chaotic dynamical systems
We prove stochastic stability of chaotic maps for a general class of Markov
random perturbations (including singular ones) satisfying some kind of mixing
conditions. One of the consequences of this statement is the proof of Ulam's
conjecture about the approximation of the dynamics of a chaotic system by a
finite state Markov chain. Conditions under which the localization phenomenon
(i.e. stabilization of singular invariant measures) takes place are also
considered. Our main tools are the so called bounded variation approach
combined with the ergodic theorem of Ionescu-Tulcea and Marinescu, and a random
walk argument that we apply to prove the absence of ``traps'' under the action
of random perturbations.Comment: 27 pages, LaTe
Salutogenesis for thriving societies
Settings are defined by the World Health Organization (1998) as “the place or social context in which people engage in daily activities in which environmental, organizational, and personal factors interact to affect health and well-being.” Such settings range from small-scale home/family to (international) organizations and large cities and thus differ in size, in their degree of formalized organization and their relationships to society.
The chapters in Part V review how salutogenesis has been applied to health promotion research and practice in a broad range of settings: organizations in general, schools, higher education, workplace, military settings, neighborhood/communities, cities, and restorative environments. The following synthesis demonstrates that applying salutogenesis to various settings and linking salutogenesis with other models established in these settings has the great potential to generate ideas on how to advance the general salutogenic model
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