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1.
Heliyon ; 9(6): e16468, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37416634

RESUMO

The traditional parameter estimation methods for photovoltaic (PV) module are strictly limited by the reference standards. On the basis of the double diode model (DDM), this paper proposes a modified PV module that is independent of the reference conditions and can be used for the transformation and reconfiguration of PV module. With respect to the issue of the slow convergence precision and the tendency to trap in the local extremum of the QUATRE algorithm, this research incorporates the QUATRE algorithm with recombination mechanism (RQUATRE) to tackle the problem of parameter estimation for the improved PV modules described above. Simulation data show that the RQUATRE wins 29, 29, 21, 17 and 15 times with the FMO, PIO, QUATRE, PSO and GWO algorithms on the CEC2017 test suite. In addition, in a modified PV module for the parameter extraction problem, the final experimental results achieved a value of 2.99 × 10-3 at RMSE, all better than the accuracy values of the compared algorithms. In the fitting process of IAE, the final values are also all less than 10%, which can satisfy the fitting needs.

2.
Entropy (Basel) ; 25(2)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36832683

RESUMO

Meta-heuristic algorithms are widely used in complex problems that cannot be solved by traditional computing methods due to their powerful optimization capabilities. However, for high-complexity problems, the fitness function evaluation may take hours or even days to complete. The surrogate-assisted meta-heuristic algorithm effectively solves this kind of long solution time for the fitness function. Therefore, this paper proposes an efficient surrogate-assisted hybrid meta-heuristic algorithm by combining the surrogate-assisted model with gannet optimization algorithm (GOA) and the differential evolution (DE) algorithm, abbreviated as SAGD. We explicitly propose a new add-point strategy based on information from historical surrogate models, using information from historical surrogate models to allow the selection of better candidates for the evaluation of true fitness values and the local radial basis function (RBF) surrogate to model the landscape of the objective function. The control strategy selects two efficient meta-heuristic algorithms to predict the training model samples and perform updates. A generation-based optimal restart strategy is also incorporated in SAGD to select suitable samples to restart the meta-heuristic algorithm. We tested the SAGD algorithm using seven commonly used benchmark functions and the wireless sensor network (WSN) coverage problem. The results show that the SAGD algorithm performs well in solving expensive optimization problems.

3.
Inf Syst Front ; : 1-15, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36118952

RESUMO

With the increasing penetration of renewable energy, uncertainty has become the main challenge of power systems operation. Fortunately, system operators could deal with the uncertainty by adopting stochastic optimization (SO), robust optimization (RO) and distributionally robust optimization (DRO). However, choosing a good decision takes much experience, which can be difficult when system operators are inexperienced or there are staff shortages. In this paper, a decision-making approach containing robotic assistance is proposed. First, advanced clustering and reduction methods are used to obtain the scenarios of renewable generation, thus constructing a scenario-based ambiguity set of distributionally robust unit commitment (DR-UC). Second, a DR-UC model is built according to the above time-series ambiguity set, which is solved by a hybrid algorithm containing improved particle swarm optimization (IPSO) and mathematical solver. Third, the above model and solution algorithm are imported into robots that assist in decision making. Finally, the validity of this research is demonstrated by a series of experiments on two IEEE test systems.

4.
Comput Biol Med ; 72: 256-62, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26868966

RESUMO

In recent years, the Japanese Ministry of Health, Labour, and Welfare is working to improve citizen׳s lifestyle and social environment to improve their health. This is because of the following reasons. Diseases related to lifestyle such as malignant neoplasms, heart disease, and cerebrovascular disease account for about 60% of the deaths in 2013. In addition, 32% of all medical expenditures are made on lifestyle-related disease. Lifestyle-related diseases can be prevented by daily exercise, a well-balanced diet, and not smoking. This ministry is promoting measures such as dietary education, physical activity, and exercise. Improvement of diet is the easiest way to reduce the occurrence of lifestyle-related diseases. Thus, in this paper, we analyze the relation between health and diet using our fuzzy robust regression model.


Assuntos
Comportamento Alimentar , Lógica Fuzzy , Modelos Teóricos , Comportamentos Relacionados com a Saúde , Humanos , Japão , Estilo de Vida
5.
IEEE Trans Neural Netw Learn Syst ; 26(5): 933-50, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25014967

RESUMO

Wafer defect detection using an intelligent system is an approach of quality improvement in semiconductor manufacturing that aims to enhance its process stability, increase production capacity, and improve yields. Occasionally, only few records that indicate defective units are available and they are classified as a minority group in a large database. Such a situation leads to an imbalanced data set problem, wherein it engenders a great challenge to deal with by applying machine-learning techniques for obtaining effective solution. In addition, the database may comprise overlapping samples of different classes. This paper introduces two models of evolutionary fuzzy ARTMAP (FAM) neural networks to deal with the imbalanced data set problems in a semiconductor manufacturing operations. In particular, both the FAM models and hybrid genetic algorithms are integrated in the proposed evolutionary artificial neural networks (EANNs) to classify an imbalanced data set. In addition, one of the proposed EANNs incorporates a facility to learn overlapping samples of different classes from the imbalanced data environment. The classification results of the proposed evolutionary FAM neural networks are presented, compared, and analyzed using several classification metrics. The outcomes positively indicate the effectiveness of the proposed networks in handling classification problems with imbalanced data sets.


Assuntos
Inteligência Artificial , Lógica Fuzzy , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão , Semicondutores , Algoritmos , Bases de Dados Factuais , Humanos
6.
Stud Health Technol Inform ; 207: 400-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25488246

RESUMO

In 2012, 15.13% of the total fiscal medical care expenditure was for lifestyle-related health care costs, which was approximately 179 billion yen. Lifestyle-related diseases are not only the biggest factor in reducing healthy life expectancy but also have the most significant impact on the national medical care expenditure. In addition, lifestyle-related diseases can be prevented by moderate daily exercise, a well-balanced diet, and not smoking. Our fuzzy robust regression model is a controllable model describing a target system. Therefore, our model is used to analyze the relation between medical care expenditure and selected lifestyle factors.


Assuntos
Custos de Cuidados de Saúde/estatística & dados numéricos , Gastos em Saúde/estatística & dados numéricos , Geografia , Humanos , Japão , Análise de Regressão
7.
IEEE Trans Cybern ; 44(10): 1846-57, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25222726

RESUMO

In the context of robust optimization with information granules for distributional parameters, this paper investigates a two-stage waste-to-energy feedstock flow planning problem with uncertain capacity expansion costs. The objective is to minimize the worst-case overall loss in a mean-risk criterion where the risk is measured by a conditional value-at-risk operator. As a salient feature, an integrated uncertainty is considered which consists of not only the uncertainty in distribution shapes of the uncertain variables, but also the manifold uncertainties of the mean parameters. To tackle the robust optimization under such integrated uncertainty, we first discuss a distributional robust two-stage feedstock flow planning model with precise mean parameters that handles the uncertainty in distribution shape, and the model can be equivalently transformed into a linear program (LP). Furthermore, the precise-mean-based robust model is extended into the case of multifaceted uncertainty for mean-parameters that are allowed to assume intervals, historical-data-based probabilistic estimates, and/or human-knowledge-centric fuzzy set estimates, under different circumstances. These multifaceted uncertain mean-parameters are uniformly represented by using information granules, and a granular robust optimization model is then developed which maximizes the robustness of the solution within a shortfall tolerance, and realizes a tradeoff between the solution conservativeness and robustness. It is showed that the granular robust model is equivalent to solving a series of LPs and can be efficiently handled by a nested binary search algorithm. Finally, the computational study illustrates the model performance, solution analysis, and underlines a much higher scalability of the developed robust model compared to the stochastic programming approach.


Assuntos
Fontes Geradoras de Energia , Lógica Fuzzy , Modelos Teóricos , Eliminação de Resíduos , Algoritmos , Gerenciamento de Resíduos
8.
ScientificWorldJournal ; 2014: 294183, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24723800

RESUMO

The expectation function of fuzzy variable is an important and widely used criterion in fuzzy optimization, and sound properties on the expectation function may help in model analysis and solution algorithm design for the fuzzy optimization problems. The present paper deals with some analytical properties of credibilistic expectation functions of fuzzy variables that lie in three aspects. First, some continuity theorems on the continuity and semicontinuity conditions are proved for the expectation functions. Second, a differentiation formula of the expectation function is derived which tells that, under certain conditions, the derivative of the fuzzy expectation function with respect to the parameter equals the expectation of the derivative of the fuzzy function with respect to the parameter. Finally, a law of large numbers for fuzzy variable sequences is obtained leveraging on the Chebyshev Inequality of fuzzy variables. Some examples are provided to verify the results obtained.


Assuntos
Algoritmos , Lógica Fuzzy , Modelos Estatísticos , Análise Numérica Assistida por Computador , Reconhecimento Automatizado de Padrão/métodos , Simulação por Computador , Conceitos Matemáticos
9.
IEEE Trans Nanobioscience ; 11(2): 100-10, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22665391

RESUMO

Clustering is commonly exploited in engineering, management, and science fields with the objective of revealing structure in pattern data sets. In this article, through clustering we construct meaningful collections of information granules (clusters). Although the underlying goal is obvious, its realization is fully challenging. Given their nature, clustering is a well-known NP-complete problem. The existing algorithms commonly produce some suboptimal solutions. As a vehicle of pattern clustering, we discuss in this article how to use a DNA-based algorithm. We also discuss the details of encoding being used here with statistical methods combined with the DNA-based algorithm for pattern clustering.


Assuntos
Algoritmos , Análise por Conglomerados , DNA/química , Modelos Genéticos , Reconhecimento Automatizado de Padrão/métodos , Sequência de Bases , Simulação por Computador , Dados de Sequência Molecular
10.
IEEE Trans Nanobioscience ; 10(3): 139-51, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22020105

RESUMO

Rough sets are often exploited for data reduction and classification. While they are conceptually appealing, the techniques used with rough sets can be computationally demanding. To address this obstacle, the objective of this study is to investigate the use of DNA molecules and associated techniques as an optimization vehicle to support algorithms of rough sets. In particular, we develop a DNA-based algorithm to derive decision rules of minimal length. This new approach can be of value when dealing with a large number of objects and their attributes, in which case the complexity of rough-sets-based methods is NP-hard. The proposed algorithm shows how the essential components involved in the minimization of decision rules in data processing can be realized.


Assuntos
DNA , Técnicas de Apoio para a Decisão , Algoritmos , Inteligência Artificial
11.
IEEE Trans Syst Man Cybern B Cybern ; 40(4): 1176-87, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19955039

RESUMO

The objective of this paper is to study facility-location problems in the presence of a hybrid uncertain environment involving both randomness and fuzziness. A two-stage fuzzy-random facility-location model with recourse (FR-FLMR) is developed in which both the demands and costs are assumed to be fuzzy-random variables. The bounds of the optimal objective value of the two-stage FR-FLMR are derived. As, in general, the fuzzy-random parameters of the FR-FLMR can be regarded as continuous fuzzy-random variables with an infinite number of realizations, the computation of the recourse requires solving infinite second-stage programming problems. Owing to this requirement, the recourse function cannot be determined analytically, and, hence, the model cannot benefit from the use of techniques of classical mathematical programming. In order to solve the location problems of this nature, we first develop a technique of fuzzy-random simulation to compute the recourse function. The convergence of such simulation scenarios is discussed. In the sequel, we propose a hybrid mutation-based binary ant-colony optimization (MBACO) approach to the two-stage FR-FLMR, which comprises the fuzzy-random simulation and the simplex algorithm. A numerical experiment illustrates the application of the hybrid MBACO algorithm. The comparison shows that the hybrid MBACO finds better solutions than the one using other discrete metaheuristic algorithms, such as binary particle-swarm optimization, genetic algorithm, and tabu search.


Assuntos
Algoritmos , Inteligência Artificial , Técnicas de Apoio para a Decisão , Meio Ambiente , Marketing/métodos
12.
IEEE Trans Nanobioscience ; 8(2): 181-91, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19497835

RESUMO

A novel method of interpretive structural modeling (ISM) using a DNA-based algorithm is proposed in this paper. ISM is commonly used when the current technology and its application to business administration, industrial and systems engineering, organizational behavior, etc., concern complicated or problematic issues, or situations among an element set of the given problem context for making decisions. When structuring a problem with a large number of elements in an ISM process, the crossings among elements should be minimized. This computationally complex minimization is NP-complete. The proposed algorithm describes how to calculate complex relations among elements to create a hierarchically restructured digraph. This paper also presents a new approach for applying a biological method to ISM to measure the efficiency of the algorithm in calculating a large number of elements for decision making.


Assuntos
Algoritmos , Desenho Assistido por Computador , DNA/química , Técnicas de Apoio para a Decisão , Modelos Teóricos , Simulação por Computador
13.
Biosystems ; 91(1): 1-12, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17669585

RESUMO

Clustering is regarded as a consortium of concepts and algorithms that are aimed at revealing a structure in highly dimensional data and arriving at a collection of meaningful relationships in data and information granules. The objective of this paper is to propose a DNA computing to support the development of clustering techniques. This approach is of particular interest when dealing with huge data sets, unknown number of clusters and encountering a heterogeneous character of available data. We present a detailed algorithm and show how the essential components of the clustering technique are realized through the corresponding mechanisms of DNA computing. Numerical examples offer a detailed insight into the performance of the DNA-based clustering.


Assuntos
DNA/genética , Família Multigênica/genética , Algoritmos , Sequência de Bases , Biologia Computacional , DNA/química , Dados de Sequência Molecular , Conformação de Ácido Nucleico
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