Navegando por Palavras-chave "Genetic algorithm"

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    GA-LP: A genetic algorithm based on Label Propagation to detect communities in directed networks
    (Pergamon-Elsevier Science Ltd, 2017) Francisquini, Rodrigo [UNIFESP]; Rosset, Valerio [UNIFESP]; Nascimento, Maria C. V. [UNIFESP]
    Many real-world networks have a topological structure characterized by cohesive groups of vertices. To perform the task of identifying such subsets of vertices, community detection in networks has aroused the interest of researchers and practitioners alike. In spite of the existence of various efficient community detection algorithms in the literature, most of them uses global information about the network, not applicable to distributed networks. This paper proposes a genetic-based algorithm to detect communities in directed networks based on local information to generate the offspring. The major difference between the proposed strategy and those found in the literature is the way of exploiting target regions of interest in the solution space. This step is directly influenced by the crossover operator that depends largely on the individual representation. In the introduced strategy, GA-LP, the individual is locally stored in the vertices as labels, what brings more flexibility in the system to be adapted to address applications that involve, for example, dynamic networks. In computational experiments, the proposed strategy showed an outstanding performance, being fast, achieving the best results on average in the networks tested. (C) 2017 Elsevier Ltd. All rights reserved.
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    Hybrid method with CS and BRKGA applied to the minimization of tool switches problem
    (Pergamon-Elsevier Science Ltd, 2016) Chaves, A. A. [UNIFESP]; Lorena, L. A. N.; Senne, E. L. F.; Resende, M. G. C.
    The minimization of tool switches problem (MTSP) seeks a sequence to process a set of jobs so that the number of tool switches required is minimized. The MTSP is well known to be NP-hard. This paper presents a new hybrid heuristic based on the Biased Random Key Genetic Algorithm (BRKGA) and the Clustering Search (CS). The main idea of CS is to identify promising regions of the search space by generating solutions with a metaheuristic, such as BRKGA, and clustering them to be further explored with local search heuristics. The distinctive feature of the proposed method is to simplify this clustering process. Computational results for the MTSP considering instances available in the literature are presented to demonstrate the efficacy of the CS with BRKGA. (C) 2015 Elsevier Ltd. All rights reserved.
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    Simplified and enhanced VCD analysis of cyclic peptides guided by artificial intelligence
    (RSC, 2023-07-24) Batsita Junior, João Marcos [UNIFESP]; Nicu, Valentin Paul; http://lattes.cnpq.br/4209224090500050
    CYCLIC PEPTIDES ARE PRIVILEGED STRUCTURES IN MEDICINAL CHEMISTRY, HOWEVER, THEIR SOLUTION-STATE STRUCTURE CHARACTERIZATION IS DIFFICULT. VIBRATIONAL CIRCULAR DICHROISM (VCD) SPECTROSCOPY IS A POWERFUL ALTERNATIVE TO NMR, BUT REQUIRES CHALLENGING CALCULATIONS. WE PRESENT A VCD APPROACH GUIDED BY A GENETIC ALGORITHM, WHICH IS SIMPLE, MORE EFFECTIVE, AND HAS HIGHER CONFORMER RESOLUTION.
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    Simultaneous optimization by neuro-genetic approach for analysis of plant materials by laser induced breakdown spectroscopy
    (Elsevier B.V., 2009-06-01) Nunes, Lidiane Cristina; Silva, Gilmare Antonia da; Trevizan, Lilian Cristina; Santos Junior, Dario [UNIFESP]; Poppi, Ronei Jesus; Krug, Francisco Jose; Universidade de São Paulo (USP); Universidade Federal de São Carlos (UFSCar); Univ Fed Ouro Preto; Universidade Federal de São Paulo (UNIFESP); Universidade Estadual de Campinas (UNICAMP)
    A simultaneous optimization strategy based on a neuro-genetic approach is proposed for selection of laser induced breakdown spectroscopy operational conditions for the simultaneous determination of macronutrients (Ca, Mg and P), micro-nutrients (B, Cu, Fe, Mn and Zn), Al and Si in plant samples. A laser induced breakdown spectroscopy system equipped with a 10 Hz Q-switched Nd:YAG laser (12 ns, 532 nm, 140 mJ) and an Echelle spectrometer with intensified coupled-charge device was used. Integration time gate, delay time, amplification gain and number of pulses were optimized. Pellets of spinach leaves (NIST 1570a) were employed as laboratory samples. in order to find a model that could correlate laser induced breakdown spectroscopy operational conditions with compromised high peak areas of all elements simultaneously, a Bayesian Regularized Artificial Neural Network approach was employed. Subsequently, a genetic algorithm was applied to find optimal conditions for the neural network model, in an approach called neuro-genetic, A single laser induced breakdown spectroscopy working condition that maximizes peak areas of all elements simultaneously, was obtained with the following optimized parameters: 9.0 mu s integration time gate, 1.1 mu s delay time, 225 (a.u.) amplification gain and 30 accumulated laser pulses. the proposed approach is a useful and a suitable tool for the optimization process of such a complex analytical problem. (C) 2009 Elsevier B.V. All rights reserved.
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    Solving the 3D stowage planning problem integrated with the quay crane scheduling problem by representation by rules and genetic algorithm
    (Elsevier Science Bv, 2018) Azevedo, Anibal Tavares; Salles Neto, Luiz Leduino de [UNIFESP]; Chaves, Antonio Augusto [UNIFESP]; Moretti, Antonio Carlos
    The operational efficiency of a port depends on proper container movement planning, called stowage planning, especially because unloading and loading container ships demands time, and this has a cost. Thus, the optimization of operations through stages is important to avoid blockage activities. This paper proposes a framework for solving the 3D stowage planning (3D SP) problem for container ships integrated with the scheduling of quay cranes (SQC) problem. 3D SP and SQC problems are interrelated and combinatorial, justifying the applications of meta-heuristics like a genetic algorithm combined with simulation and representation by rules. The robustness of the developed approach is attested in problems with 30 ports, 1500 TEUs ship or 15 ports and 22,000 TEUs ship and two quay cranes. These studies showed that the addition of the SQC problem leads to a 45.82% increase in load/unload time for the 3D SP problem solution, on average. This could help the charterer to avoid paying charges to the shipowner due to its an extra unplanned use of the vessel. Additionally, the developed methodology also helps to explain a long term phenomena of continuous increasing in container ship capacity since 1950s. (c) 2018 Elsevier B.V. All rights reserved.