genetic algorithm

遗传算法
  • 文章类型: Journal Article
    GM(1,1)模型的预测精度受背景值估计精度的影响较大。传统的梯形背景值只能应用于特定的数据序列。因此,为了提高模型的应用和预测精度,提出了一种基于智能梯形和变权相结合的GM(1,1)模型背景值重构方法。具有斜率和点位置参数的梯形背景值函数称为模型I。然后,一组点位置参数序列,构造了一个新的背景值函数,称为模型II。利用遗传算法来寻求要在模型I和II中确定的参数值。结果表明,对于指数增长数据序列,与传统模型相比,模型I和模型II具有更高的预测精度。对于数据序列,以某条道路2014-2023年的交通量序列为例,本文模型I方法的预测精度与邓氏和王氏模型相比可分别提高0.3643%和0.2725%。本文模型Ⅱ法的预测精度比模型Ⅰ法进一步提高了0.1075%
    The GM(1,1) model\'s prediction accuracy is significantly influenced by the accuracy of background value estimation. The traditional trapezoidal background value can only be applied to a specific data sequence. Therefore, this study proposes a GM(1,1) model background value reconstruction approach based on the combination of intelligent trapezoidal and variable weights in order to increase the model\'s application as well as its prediction accuracy. The trapezoidal background value function with slope and point position parameters is called model I. Then, a set of point position parameter sequences, with a new background value function is constructed, called model II. A genetic algorithm is utilized to seek for the values of the parameters to be determined in both models I and II. The results showed that for the exponential growth data series, model I and II have higher prediction accuracy compared to traditional models. For data sequences, taking the traffic volume series of a road from 2014 to 2023, the prediction accuracy of this paper\'s model I method can be improved by 0.3643 % and 0.2725 % compared with Deng\'s and Wang\'s models. The prediction accuracy of this paper\'s model II method has been further improved by 0.1075 % compared with that of model I.
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  • 文章类型: Journal Article
    含有微胶囊相变材料(MPCM)的悬浮液在热能存储(TES)系统中起着至关重要的作用,并在建筑材料中具有应用。纺织品,和冷却系统。这项研究的重点是准确预测动态粘度,一个关键的热物理性质,使用高斯过程回归(GPR)对含有MPCM和MXene颗粒的悬浮液进行分析。分别分析了十二种GPR超参数(HP),并根据其重要性分为三组。三种元启发式算法,即遗传算法(GA),粒子群优化(PSO),和海洋捕食者算法(MPA),用于优化HP。优化四个最重要的超参数(协方差函数,基函数,标准化,和sigma)在第一组中使用三种元启发式算法中的任何一种都会产生出色的结果。所有算法都达到了合理的R值(0.9983),证明他们在这方面的有效性。第二组探讨了包括其他因素的影响,中度显著的HP,例如拟合方法,预测方法和优化器。虽然所得到的模型比第一组有一些改善,该组中基于PSO的模型表现出最值得注意的增强,实现更高的R值(0.99834)。最后,对第三组进行了分析,以检查所有12个HP之间的潜在相互作用.这种全面的方法,雇用GA,产生了具有最高目标合规性的优化GPR模型,反映在令人印象深刻的R值0.999224。开发的模型是一种具有成本效益和高效的解决方案,以降低各种系统的实验室成本,从TES到热管理。
    Suspensions containing microencapsulated phase change materials (MPCMs) play a crucial role in thermal energy storage (TES) systems and have applications in building materials, textiles, and cooling systems. This study focuses on accurately predicting the dynamic viscosity, a critical thermophysical property, of suspensions containing MPCMs and MXene particles using Gaussian process regression (GPR). Twelve hyperparameters (HPs) of GPR are analyzed separately and classified into three groups based on their importance. Three metaheuristic algorithms, namely genetic algorithm (GA), particle swarm optimization (PSO), and marine predators algorithm (MPA), are employed to optimize HPs. Optimizing the four most significant hyperparameters (covariance function, basis function, standardization, and sigma) within the first group using any of the three metaheuristic algorithms resulted in excellent outcomes. All algorithms achieved a reasonable R-value (0.9983), demonstrating their effectiveness in this context. The second group explored the impact of including additional, moderate-significant HPs, such as the fit method, predict method and optimizer. While the resulting models showed some improvement over the first group, the PSO-based model within this group exhibited the most noteworthy enhancement, achieving a higher R-value (0.99834). Finally, the third group was analyzed to examine the potential interactions between all twelve HPs. This comprehensive approach, employing the GA, yielded an optimized GPR model with the highest level of target compliance, reflected by an impressive R-value of 0.999224. The developed models are a cost-effective and efficient solution to reduce laboratory costs for various systems, from TES to thermal management.
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  • 文章类型: Journal Article
    随着全球人口老龄化的加剧,老年人监护系统的效率和准确性变得至关重要。在本文中,一种传感器布局优化方法,融合遗传灰狼优化(FGGWO)算法,提出了利用遗传算法(GA)的全局搜索能力和灰狼优化算法(GWO)的局部搜索能力来提高老年人监测系统中传感器布局的效率和准确性。通过优化室内红外传感器在老年人监护系统中的布局来提高传感器在老年人监护系统中的布局效率和覆盖率。测试结果表明,FGGWO算法在监控覆盖率方面优于单一优化算法,准确度,和系统效率。此外,该算法能够有效地避免传统方法中普遍存在的局部最优问题,减少传感器的使用数量,同时保持较高的监测精度。该算法的灵活性和适应性预示着其在广泛的智能监控场景中的潜在应用。未来的研究将探讨如何将深度学习技术集成到FGGWO算法中,以进一步增强系统的自适应和实时响应能力。
    With the increasing aging of the global population, the efficiency and accuracy of the elderly monitoring system become crucial. In this paper, a sensor layout optimization method, the Fusion Genetic Gray Wolf Optimization (FGGWO) algorithm, is proposed which utilizes the global search capability of Genetic Algorithm (GA) and the local search capability of Gray Wolf Optimization algorithm (GWO) to improve the efficiency and accuracy of the sensor layout in elderly monitoring systems. It does so by optimizing the indoor infrared sensor layout in the elderly monitoring system to improve the efficiency and coverage of the sensor layout in the elderly monitoring system. Test results show that the FGGWO algorithm is superior to the single optimization algorithm in monitoring coverage, accuracy, and system efficiency. In addition, the algorithm is able to effectively avoid the local optimum problem commonly found in traditional methods and to reduce the number of sensors used, while maintaining high monitoring accuracy. The flexibility and adaptability of the algorithm bode well for its potential application in a wide range of intelligent surveillance scenarios. Future research will explore how deep learning techniques can be integrated into the FGGWO algorithm to further enhance the system\'s adaptive and real-time response capabilities.
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  • 文章类型: Journal Article
    近年来,基于单源数据的深度学习方法在故障诊断领域取得了长足的进步。然而,从多源数据中提取有用信息仍然是一个挑战。在本文中,我们提出了一种新的方法称为遗传模拟退火优化(GASA)方法与多源数据卷积神经网络(MSCNN)用于滚动轴承的故障诊断。该方法旨在更准确地识别轴承故障,充分利用多源数据。最初,使用连续小波变换(CWT)将轴承振动信号转换为时频图,并将该信号与电动机电流信号集成并馈送到网络模型中。然后,建立了GASA-MSCNN故障诊断方法,以更好地捕获信号中的关键信息并识别各种轴承健康状态。最后,采用不同噪声环境下的滚动轴承数据集来验证所提出模型的鲁棒性。实验结果表明,该方法能够准确识别各类滚动轴承故障,即使在可变噪声环境中,准确率也高达98%或更高。实验表明,新方法显著提高了故障检测的准确性。
    In recent years, single-source-data-based deep learning methods have made considerable strides in the field of fault diagnosis. Nevertheless, the extraction of useful information from multi-source data remains a challenge. In this paper, we propose a novel approach called the Genetic Simulated Annealing Optimization (GASA) method with a multi-source data convolutional neural network (MSCNN) for the fault diagnosis of rolling bearing. This method aims to identify bearing faults more accurately and make full use of multi-source data. Initially, the bearing vibration signal is transformed into a time-frequency graph using the continuous wavelet transform (CWT) and the signal is integrated with the motor current signal and fed into the network model. Then, a GASA-MSCNN fault diagnosis method is established to better capture the crucial information within the signal and identify various bearing health conditions. Finally, a rolling bearing dataset under different noisy environments is employed to validate the robustness of the proposed model. The experimental results demonstrate that the proposed method is capable of accurately identifying various types of rolling bearing faults, with an accuracy rate reaching up to 98% or higher even in variable noise environments. The experiments reveal that the new method significantly improves fault detection accuracy.
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  • 文章类型: Journal Article
    传统作物籽粒中Cd含量的预测主要依赖于基于土壤Cd含量(Cds)和pH值的多元线性回归模型,忽略外部环境因素与Cdg之间的因素间相互作用和非线性因果关系。在这项研究中,包括土壤特性在内的多类型环境因子的综合指标体系,地质学,气候,并建立了人为活动。基于树的集成的机器学习模型,支持向量回归,基于环境因子指标的人工神经网络预测水稻和小麦的Cdg比传统的基于土壤性质的线性回归模型的精度明显提高。其中,XGboost和随机森林的基于树的集成模型在预测水稻和小麦的Cdg方面表现出最高的准确性,测试数据集中的R2分别为0.349和0.546。这项研究发现,土壤性质,包括CD,pH值,和粘土,对水稻和小麦的Cdg有较大影响,综合贡献率分别为65.2%和29.7%。由于小麦采样区位于中国中部和北部,与南部的水稻采样区相比,它们受降水和温度的限制更大。地质和气候因素对小麦Cdg的影响较大,综合贡献率为49.9%,高于水稻相应的20.9%。此外,水稻和小麦的Cdg与Cds没有绝对的线性关系,过高的Cds会降低作物Cd积累的生物富集因子。同时,其他环境因素,如温度,降水,海拔对作物Cdg的增加有边际效应。本研究为优化传统土壤植物转移模型提供了一个新的框架,为实现作物中Cd含量的高精度预测提供了一步。
    The traditional prediction of the Cd content in grains (Cdg) of crops primarily relies on the multiple linear regression models based on soil Cd content (Cds) and pH, neglecting inter-factorial interactions and nonlinear causal links between external environmental factors and Cdg. In this study, a comprehensive index system of multi-type environmental factors including soil properties, geology, climate, and anthropogenic activity was constructed. The machine learning models of the tree-based ensemble, support vector regression, artificial neural network for predicting Cdg of rice and wheat based on the environmental factor indexes significantly improved the accuracy than the traditional models of linear regression based on soil properties. Among them, the tree-based ensemble models of XGboost and random forest exhibited highest accuracies for predicting Cdg of rice and wheat, with R2 in the test dataset of 0.349 and 0.546, respectively. This study found that soil properties, including Cds, pH, and clay, have greater impacts on Cdg of rice and wheat, with combined contribution rates accounting for 65.2 % and 29.7 % respectively. Since wheat sampling areas are located in central and northern China, they are more constrained by precipitation and temperature than rice sampling areas in the south. Geologic and climate factors have a greater impact on Cdg of wheat, with a combined contribution rate of 49.9 %, which is higher than the corresponding rate of 20.9 % in rice. Furthermore, the Cdg of rice and wheat did not exhibit an absolute linear relationship with Cds, and excessively high Cds can reduce the bioconcentration factor of Cd accumulation in crops. Meanwhile, other environmental factors such as temperature, precipitation, elevation have marginal effects on the increase of Cdg of crops. This study provides a novel framework to optimize traditional soil plant transfer models, as well as offer a step towards realizing high precision prediction of Cd content in crops.
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  • 文章类型: Journal Article
    近年来,由于边缘和云计算的结合,边缘云计算受到了越来越多的关注。任务调度仍然是提高边缘云服务质量和资源效率的主要挑战之一。尽管已经对调度问题进行了一些研究,它们的应用仍然需要解决的问题,例如,忽略资源异质性,只关注一种请求。因此,在本文中,我们的目标是提供一种异构感知的任务调度算法,以提高具有截止日期限制的边缘云的任务完成率和资源利用率。由于调度问题的NP硬度,我们利用遗传算法(GA),最具代表性和广泛使用的元启发式算法之一,为了解决将任务完成率和资源利用率作为主要和次要优化目标的问题,分别。在我们基于GA的调度算法中,基因指示其对应的任务由哪个资源处理。为了提高GA的性能,我们建议利用偏斜突变算子,其中基因在种群进化过程中与资源异质性相关。我们进行了大量的实验来评估我们算法的性能,结果验证了算法在任务完成率方面的优越性,与其他13种经典和最新的调度算法相比。
    Recent years, edge-cloud computing has attracted more and more attention due to benefits from the combination of edge and cloud computing. Task scheduling is still one of the major challenges for improving service quality and resource efficiency of edge-clouds. Though several researches have studied on the scheduling problem, there remains issues needed to be addressed for their applications, e.g., ignoring resource heterogeneity, focusing on only one kind of requests. Therefore, in this paper, we aim at providing a heterogeneity aware task scheduling algorithm to improve task completion rate and resource utilization for edge-clouds with deadline constraints. Due to NP-hardness of the scheduling problem, we exploit genetic algorithm (GA), one of the most representative and widely used meta-heuristic algorithms, to solve the problem considering task completion rate and resource utilization as major and minor optimization objectives, respectively. In our GA-based scheduling algorithm, a gene indicates which resource that its corresponding task is processed by. To improve the performance of GA, we propose to exploit a skew mutation operator where genes are associated to resource heterogeneity during the population evolution. We conduct extensive experiments to evaluate the performance of our algorithm, and results verify the performance superiority of our algorithm in task completion rate, compared with other thirteen classical and up-to-date scheduling algorithms.
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  • 文章类型: Journal Article
    MesonachinensisBenth(MCB)是东南亚和中国最常用的草药饮料的来源,因此是经济上重要的农业植物。因此,优化的提取和生产程序具有显著的商业价值。目前,在绿色化学方面,研究人员正在研究使用更环保的溶剂和创新的提取技术,以提高提取物的产量。这项研究代表了对从MCB中超声辅助的低共熔溶剂(DES)萃取的最佳条件的首次研究。利用响应面法中心-遗传算法-反向传播神经网络对影响超声辅助DES的主要因素进行了优化。与RSM模型相比,该模型具有更高的可预测性和准确性。各种类型的DES用于MCB成分的提取,与氯化胆碱-乙二醇产生最高的产量。最大提取的最佳条件是使用氯化胆碱-乙二醇(1:4)作为水含量为40%的溶剂,在60°C下提取60分钟,并且保持叶与溶剂的比率为20mL/g。相对于使用乙醇观察到的那些,观察到范德华力的显著增强和DES和目标化学物质之间更稳健的相互作用(70%,v/v)或水。该研究不仅引入了从MCB高效提取的环境友好的方法,而且还确定了改进提取功效的潜在机制。这些发现有可能有助于MCB的更广泛利用,并为利用低共熔溶剂的提取机制提供有价值的见解。实际应用:这项工作描述了一种有效的绿色超声辅助的低共熔溶剂(DES)方法,用于MesonachinensisBenth(MCB)提取。分子动力学用于检查溶剂与提取的化合物之间的分子间相互作用。预计绿色环保溶剂,例如DES,将用于食品及其生物活性成分的进一步研究。随着凉茶产业的发展,由MCB制成的新产品越来越受欢迎,逐渐成为研究热点。
    Mesona chinensis Benth (MCB) is the source of the most commonly consumed herbal beverage in Southeast Asia and China and is thus an economically important agricultural plant. Therefore, optimal extraction and production procedures have significant commercial value. Currently, in terms of green chemistry, researchers are investigating the use of greener solvents and innovative extraction techniques to increase extract yields. This study represents the first investigation of the optimal conditions for ultrasound-assisted deep eutectic solvent (DES) extraction from MCB. The major factors influencing ultrasound-assisted DESs were optimized using the response surface methodcentral-genetic algorithm-back propagation neural networks. This model demonstrated superior predictability and accuracy compared to the RSM model. Various types of DESs were used for the extraction of MCB constituents, with choline chloride-ethylene glycol resulting in the highest yield. The optimal conditions for maximal extraction were the use of choline chloride-ethylene glycol (1:4) as the solvent with a 40% water content, an extraction duration of 60 min at 60°C, and maintaining a leaf-to-solvent ratio of 20 mL/g. Noticeable enhancements in Van der Waals forces and more robust interactions between DESs and the target chemicals were observed relative to those seen with ethanol (70%, v/v) or water. This investigation not only introduced an environmentally friendly approach for highly efficient extraction from MCB but also identified the mechanisms underlying the improved extraction efficacy. These findings have the potential to contribute to the broader utilization of MCB and provide valuable insights into the extraction mechanisms utilizing deep eutectic solvents. PRACTICAL APPLICATION: This work describes an efficient and green ultrasound-assisted deep eutectic solvent (DES) method for Mesona chinensis Benth (MCB) extraction. Molecular dynamics was used to examine the intermolecular interactions between the solvent and the extracted compounds. It is anticipated that green and environmentally friendly solvents, such as DESs, will be used in further research on foods and their bioactive components. With the development of the herbal tea industry, new products made of MCB are becoming increasingly popular, thus gradually making it a research hotspot.
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  • 文章类型: Journal Article
    自主农业机器人多区域作业中的无碰撞路径规划和任务调度优化存在复杂的耦合问题。除了考虑任务访问顺序和无冲突路径规划外,多个因素,如任务优先级,农田地形的复杂性,必须全面解决机器人能耗问题。本研究旨在探索一种分层解耦方法来应对多区域路径规划的挑战。首先,基于A*算法进行路径规划,遍历所有任务的路径,得到多区域连通路径。在整个过程中,路径长度等因素,转折点,角角度被彻底考虑,并为后续优化过程构建成本矩阵。其次,我们将多区域路径规划问题重新构造为离散优化问题,并采用遗传算法优化任务序列,从而确定能量约束下的最优任务执行顺序。最后在开放环境下进行实验,验证了多任务规划算法的可行性。狭窄的环境和大规模的环境。实验结果表明,该方法能够在复杂的多区域规划场景中找到可行的无冲突和成本最优的任务访问路径。
    Collision-free path planning and task scheduling optimization in multi-region operations of autonomous agricultural robots present a complex coupled problem. In addition to considering task access sequences and collision-free path planning, multiple factors such as task priorities, terrain complexity of farmland, and robot energy consumption must be comprehensively addressed. This study aims to explore a hierarchical decoupling approach to tackle the challenges of multi-region path planning. Firstly, we conduct path planning based on the A* algorithm to traverse paths for all tasks and obtain multi-region connected paths. Throughout this process, factors such as path length, turning points, and corner angles are thoroughly considered, and a cost matrix is constructed for subsequent optimization processes. Secondly, we reformulate the multi-region path planning problem into a discrete optimization problem and employ genetic algorithms to optimize the task sequence, thus identifying the optimal task execution order under energy constraints. We finally validate the feasibility of the multi-task planning algorithm proposed by conducting experiments in an open environment, a narrow environment and a large-scale environment. Experimental results demonstrate the method\'s capability to find feasible collision-free and cost-optimal task access paths in diverse and complex multi-region planning scenarios.
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  • 文章类型: Journal Article
    基因组选择(GS)已成为一种有效的技术,可通过在表型收集之前进行早期选择来加速作物杂种育种。基因组最佳线性无偏预测(GBLUP)是一种稳健的方法,已在GS育种程序中常规使用。然而,GBLUP假设标记对总遗传变异的贡献相等,情况可能并非如此。在这项研究中,我们开发了一种称为GA-GBLUP的新型GS方法,该方法利用遗传算法(GA)来选择与目标性状相关的标记。我们定义了四个优化的适应度函数,包括AIC,BIC,R2和帽子,基于连锁不平衡原理,降低模型维数,提高相邻标记的可预测性和bin。结果表明,GA-GBLUP模型,配备R2和HAT健身功能,对于水稻和玉米数据集中的大多数性状,产生比GBLUP高得多的可预测性,特别是对于低遗传力的性状。此外,我们开发了一个用户友好的R包,GAGBLUP,对于GS,并且该软件包在CRAN上免费提供(https://CRAN。R-project.org/package=GAGBLUP)。
    Genomic selection (GS) has emerged as an effective technology to accelerate crop hybrid breeding by enabling early selection prior to phenotype collection. Genomic best linear unbiased prediction (GBLUP) is a robust method that has been routinely used in GS breeding programs. However, GBLUP assumes that markers contribute equally to the total genetic variance, which may not be the case. In this study, we developed a novel GS method called GA-GBLUP that leverages the genetic algorithm (GA) to select markers related to the target trait. We defined four fitness functions for optimization, including AIC, BIC, R2, and HAT, to improve the predictability and bin adjacent markers based on the principle of linkage disequilibrium to reduce model dimension. The results demonstrate that the GA-GBLUP model, equipped with R2 and HAT fitness function, produces much higher predictability than GBLUP for most traits in rice and maize datasets, particularly for traits with low heritability. Moreover, we have developed a user-friendly R package, GAGBLUP, for GS, and the package is freely available on CRAN (https://CRAN.R-project.org/package=GAGBLUP).
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  • 文章类型: Journal Article
    高性能混凝土(HPC)抗压强度与其组分之间存在复杂的高维非线性映射关系,对抗压强度的准确预测有很大影响。在本文中,结合BP神经网络(BPNN)的高效稳健软件计算策略,提出了支持向量机(SVM)和遗传算法(GA)用于HPC的抗压强度预测。从以前的文献中提取了8个特征,构建了包含454组数据的抗压强度数据库。对模型进行了训练和测试,以及4个机器学习(ML)模型的性能,即BPNN,SVM,GA-BPNN和GA-SVM,比较。结果表明,耦合模型优于单一模型。此外,由于GA-SVM具有较好的泛化能力和理论基础,其收敛速度和预测精度均优于GA-BPNN。然后利用灰色关联分析(GRA)和Shapley分析验证了GA-SVM模型的可解释性,结果表明,水胶比对抗压强度的影响最大。最后,多输入变量的组合来评估抗压强度,补充了本研究,并再次验证了水胶比的显著影响,为后续研究提供参考价值。
    There is a complex high-dimensional nonlinear mapping relationship between the compressive strength of High-Performance Concrete (HPC) and its components, which has great influence on the accurate prediction of compressive strength. In this paper, an efficient robust software calculation strategy combining BP Neural Network (BPNN), Support Vector Machine (SVM) and Genetic Algorithm (GA) is proposed for the prediction of compressive strength of HPC. 8 features were extracted from the previous literature, and a compressive strength database containing 454 sets of data was constructed. The model was trained and tested, and the performance of 4 Machine Learning (ML) models, namely BPNN, SVM, GA-BPNN and GA-SVM, was compared. The results show that the coupled model is superior to the single model. Moreover, because GA-SVM has better generalization ability and theoretical basis, its convergence speed and prediction accuracy are better than GA-BPNN. Then Grey Relational Analysis (GRA) and Shapley analysis were used to verify the interpretability of the GA-SVM model, which showed that the water-binder ratio had the most significant influence on the compressive strength. Finally, the combination of multiple input variables to evaluate the compressive strength supplemented this research, and again verified the significant influence of water-binder ratio, providing reference value for subsequent research.
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