Accurate state of charge(SOC) estimation is of great significance for a lithium-ion battery to ensure its safe operation and prevent it from over-charging or ***,it is difficult to get an accurate value of SOC since i...
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Accurate state of charge(SOC) estimation is of great significance for a lithium-ion battery to ensure its safe operation and prevent it from over-charging or ***,it is difficult to get an accurate value of SOC since it is an inner state of a battery cell,which cannot be directly *** order to improve the estimation accuracy of SOC,this paper develops a SOC estimation model for a lithium-ion battery using a particleswarmoptimization-Extreme Learning Machine(PSO-ELM) *** PSO is applied to determine the optimal value of hidden layer neurons and the learning rate since these parameters are the most critical factors in constructing an optimal ELM *** inputs to the PSO-ELM model are the battery voltage,current,and temperature,and the output is the actual SOC *** performance of the proposed model is compared with BP neural network and ELM models and verified based on the mean square error(MSE),mean absolute error(MAE),mean absolute percentage error(MAPE),and SOC *** results demonstrate that the PSO-ELM model offers higher accuracy and lower SOC error rate than ELM and BP neural network models.
Financial support for water conservancy construction is an important approach to promote the development of water conservancy economy. In order to deal with numerical solution for stock option in water conservancy fin...
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Financial support for water conservancy construction is an important approach to promote the development of water conservancy economy. In order to deal with numerical solution for stock option in water conservancy finance, a hybrid optimizationalgorithm is proposed. By virtue of the relation between Black-Scholes model and heat equation, a class of heat equations with initial-boundary values is established based on Schwarz waveform relaxation algorithm, meanwhile particle swarm optimization algorithm is applied to estimate parameters in option pricing model. In numerical experiments, the hybrid optimizationalgorithm is used to seek the approximate value of call option based on water concept stock, and it obtains better estimation results than existed methods.
Although the algorithms for cluster analysis are continually improving, most clustering algorithms still need to set the number of clusters. Thus, this study proposes a novel dynamic clustering approach based on parti...
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Although the algorithms for cluster analysis are continually improving, most clustering algorithms still need to set the number of clusters. Thus, this study proposes a novel dynamic clustering approach based on particleswarmoptimization (PSO) and genetic algorithm (GA) (DCPG) algorithm. The proposed DCPG algorithm can automatically cluster data by examining the data without a pre-specified number of clusters. The computational results of four benchmark data sets indicate that the DCPG algorithm has better validity and stability than the dynamic clustering approach based on binary-PSO (DCPSO) and the dynamic clustering approach based on GA (DCGA) algorithms. Furthermore, the DCPG algorithm is applied to cluster the bills of material (BOM) for the Advantech Company in Taiwan. The clustering results can be used to categorize products which share the same materials into clusters. (C) 2012 Elsevier Inc. All rights reserved.
The direct-condensation radiant heating panel (DRHP) is considered as an efficient heating terminal in space heating. In this study, a numerical-based optimization approach is proposed for the thermoeconomic performan...
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The direct-condensation radiant heating panel (DRHP) is considered as an efficient heating terminal in space heating. In this study, a numerical-based optimization approach is proposed for the thermoeconomic performance improvement of the DRHP. An improved numerical model of the DRHP considering the heat conduction of the composite straight-and-circular fins and that of the connecting segments is established. The analytical solutions of the heat conduction of the composite straight-and-circular fins are derived to improve the prediction accuracy and computation speed. The model is validated by the experimental data. Based on the proposed model, the particleswarmoptimization (PSO) algorithm is adopted to maximize the heating capacity under per unit cost of the DRHP. The optimization constraints are determined with the parametric analysis and the iterations are examined to be 30. Based on the optimization approach, the optimized DRHPs are obtained for heat pump units with different output powers, and the heating capacity under per unit cost of the optimized DRHP is increased by 44.2%. The proposed optimization approach is appropriate for the optimization of DRHP. (c) 2021 Elsevier B.V. All rights reserved.
COVID-19 is a global pandemic that aroused the interest of scientists to prevent it and design a drug for it. Nowadays, presenting intelligent biological data analysis tools at a low cost is important to analyze the b...
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COVID-19 is a global pandemic that aroused the interest of scientists to prevent it and design a drug for it. Nowadays, presenting intelligent biological data analysis tools at a low cost is important to analyze the biological structure of COVID-19. The global alignment algorithm is one of the important bioinformatics tools that measure the most accurate similarity between a pair of biological sequences. The huge time consumption of the standard global alignment algorithm is its main limitation especially for sequences with huge lengths. This work proposed a fast global alignment tool (G-Aligner) based on meta-heuristic algorithms that estimate similarity measurements near the exact ones at a reasonable time with low cost. The huge length of sequences leads G-Aligner based on standard Sine-Cosine optimizationalgorithm (SCA) to trap in local minima. Therefore, an improved version of SCA was presented in this work that is based on integration with PSO. Besides, mutation and opposition operators are applied to enhance the exploration capability and avoiding trapping in local minima. The performance of the improved SCA algorithm (SP-MO) was evaluated on a set of IEEE CEC functions. Besides, G-Aligner based on the SP-MO algorithm was tested to measure the similarity of real biological sequence. It was used also to measure the similarity of the COVID-19 virus with the other 13 viruses to validate its performance. The tests concluded that the SP-MO algorithm has superiority over the relevant studies in the literature and produce the highest average similarity measurements 75% of the exact one. (C) 2021 Elsevier B.V. All rights reserved.
The operational flexibility of thermal power plants is important to consume renewable energy generation, especially in the regions where combined heat and power (CHP) units account for a high proportion. Focusing on t...
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The operational flexibility of thermal power plants is important to consume renewable energy generation, especially in the regions where combined heat and power (CHP) units account for a high proportion. Focusing on the relationship between peak-shaving capacity of CHP units and the consumption of renewable energy generation, the problem about operational flexibility of CHP plants is analyzed in this paper. From the perspective of entire CHP plants rather than the renovation of one CHP unit, the problem regarding the operation scheduling without cost or risk is addressed. A plant-level operation domain model is established, which can improve the operational flexibility of CHP plants. The heat and power adjustable ranges of CHP plants were obtained by particleswarmoptimization. Also the CHP plant located in northern China was taken as an example. The power load downward adjustment range of four periods in the heating season are 9.21%, 20.44%, 14.09% and 5.31% respectively, compared with the entire plant actual power under the same heat load. Moreover, the operational flexibility of CHP plants can be enlarged by decreasing the pressure of heating extraction. Compared with the entire plant actual operating conditions, the consumption of renewable energy generation could be increased by 268.56 million kWh approximately and about 0.22 million tons CO2 emissions can be reduced per heating season if the reference plant operates with minimum power load constantly.
Trajectory planning method for the entire recovery process of the reusable launch vehicle is studied. Firstly, a revised trajectory correction method (RTCM) is proposed to reduce the maximum normal aerodynamic load in...
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Trajectory planning method for the entire recovery process of the reusable launch vehicle is studied. Firstly, a revised trajectory correction method (RTCM) is proposed to reduce the maximum normal aerodynamic load in the endo-atmosphere unpowered descent phase and improve the vehicle's landing accuracy on the influence of wind field. It consists of two parts, namely moving the ignition point of the vertical landing phase on the horizontal plane and introducing preset steady wind field into trajectory planning. Secondly, a compound trajectory planning method, which combines particle swarm optimization algorithm (PSO) with Polynomial Guidance Law (PGL), is proposed to complete the optimization task of the entire recovery process. Employing PSO algorithm can avoid the complex calculation of additional angle of attack caused by the preset steady wind field in traditional trajectory correction. To overcome the premature convergence of basic PSO, the traditional re-initialization mechanism is improved. Finally, the guidance simulation of two phases greatly affected by wind is accomplished. The effectiveness of the proposed methods is demonstrated with some scenarios and Monte Carlo simulation. (C) 2021 Elsevier Masson SAS. All rights reserved.
A new algorithm for timetabling based on particle swarm optimization algorithm was proposed, and the key problems such as particle coding, fitness function fabricating, particleswarm initialization and crossover oper...
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A new algorithm for timetabling based on particle swarm optimization algorithm was proposed, and the key problems such as particle coding, fitness function fabricating, particleswarm initialization and crossover operation were settled. The fitness value declines when the evolution generation increases. The results showed that it was a good solution for course timetabling problem in the educational system.
Hull form optimization is a typical complex engineering problem. The complex design performance space often results in a low optimization efficiency as an optimal solution cannot be ensured. Presently, several methods...
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Hull form optimization is a typical complex engineering problem. The complex design performance space often results in a low optimization efficiency as an optimal solution cannot be ensured. Presently, several methods, such as efficient optimizationalgorithms, approximate model technology, and high-performance computing are primarily used to reduce the calculation time. However, these methods cannot satisfy practical application requirements in terms of efficiency and solution accuracy. Thus, we investigated a dynamic space reduction optimization framework (DSROF), in this study, wherein data mining is continuously performed during the optimization process to dynamically reduce the range and number of variables. DSROF enables subsequent optimization only in the range that exhibits a high performance, thereby reducing redundant calculations, improving optimization efficiency, and ensuring a higher degree of accuracy. Furthermore, we applied DSROF to function examples and hull form optimization. The results indicate that the use of the DSROF can reduce the calculation cost in hull form optimization by 23% in comparison with that of the particle swarm optimization algorithm.
State-of-charge (SOC) estimation of lithium-ion battery is one of the core functions of battery management system. In order to improve the estimation accuracy of SOC, this paper proposes a long shortterm memory neural...
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State-of-charge (SOC) estimation of lithium-ion battery is one of the core functions of battery management system. In order to improve the estimation accuracy of SOC, this paper proposes a long shortterm memory neural network based on particleswarmoptimization (PSO-LSTM). Firstly, the key parameters of LSTM are optimized by PSO algorithm, so that the data characteristics of lithium-ion battery can match the network topology. In addition, random noise is added to the input layer of PSO-LSTM neural network to improve the anti-interference ability of the network. Finally, experiments show that the proposed method can achieve accurate estimation under different conditions. The estimates based on PSO-LSTM converge to the real state-of-charge within an error of 0.5%. (c) 2021 Published by Elsevier Ltd.
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