Optimization algorithm

优化算法
  • 文章类型: Journal Article
    矿区地表沉陷灾害是指矿区开采过程中常见的涉及植被退化和地面塌陷等问题的地质灾害,这也引起了人们对安全的担忧。为解决传统预测模型的准确性问题,研究露天矿区沉降预测方法,这项研究首先使用91个场景的Sentinel-1A上升和下降轨道图像来监测安宁市磷矿的长期变形,云南省,中国西南部。获得了研究区域的年平均沉降率和累积地表变形值。随后,使用时间序列配准插值方法进行二维变形分解,以确定垂直和东西变形的分布。最后,采用了三种预测模型:反向传播神经网络(BPNN),遗传算法优化的BPNN(GA-BP),用人工蜂群算法(ABC-BP)优化BPNN。这些模型用于预测六个选定的时间序列点。结果表明,BPNN模型的平均绝对误差(MAE)和均方根误差(RMSE)在7.6mm以内。而GA-BP模型误差在3.5mm以内,ABC-BP模型误差在3.7mm以内。两种优化的模型均显示出显着提高的准确性和良好的预测能力。
    Surface subsidence hazards in mining areas are common geological disasters involving issues such as vegetation degradation and ground collapse during the mining process, which also raise safety concerns. To address the accuracy issues of traditional prediction models and study methods for predicting subsidence in open-pit mining areas, this study first employed 91 scenes of Sentinel-1A ascending and descending orbits images to monitor long-term deformations of a phosphate mine in Anning City, Yunnan Province, southwestern China. It obtained annual average subsidence rates and cumulative surface deformation values for the study area. Subsequently, a two-dimensional deformation decomposition was conducted using a time-series registration interpolation method to determine the distribution of vertical and east-west deformations. Finally, three prediction models were employed: Back Propagation Neural Network (BPNN), BPNN optimized by Genetic Algorithm (GA-BP), and BPNN optimized by Artificial Bee Colony Algorithm (ABC-BP). These models were used to forecast six selected time series points. The results indicate that the BPNN model had Mean Absolute Errors (MAE) and Root Mean Squared Errors (RMSE) within 7.6 mm, while the GA-BP model errors were within 3.5 mm, and the ABC-BP model errors were within 3.7 mm. Both optimized models demonstrated significantly improved accuracy and good predictive capabilities.
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  • 文章类型: Journal Article
    图像数字水印是版权保护和图像安全的重要方法。本文提出了一种创新的,基于矩和小波变换的彩色图像鲁棒水印系统,代数分解,和混沌系统。首先,我们使用四元数代数将经典Charlier矩扩展到四元Charlier矩(QCM)。这种方法消除了在应用离散小波变换(DWT)之前分解彩色图像的需要,减少计算负荷。接下来,我们使用QR和奇异值分解(SVD)分解得到的DWT矩阵。为了增强系统的安全性和健壮性,我们介绍了Henon的2D混沌图的修改版本。最后,我们集成了算术优化算法,以确保动态和自适应的水印插入。我们的实验结果表明,我们的方法在安全性方面优于当前的彩色图像水印方法,存储容量,抵抗各种攻击,同时保持高水平的隐形。
    Digital watermarking of images is an essential method for copyright protection and image security. This paper presents an innovative, robust watermarking system for color images based on moment and wavelet transformations, algebraic decompositions, and chaotic systems. First, we extended classical Charlier moments to quaternary Charlier moments (QCM) using quaternion algebra. This approach eliminates the need to decompose color images before applying the discrete wavelet transform (DWT), reducing the computational load. Next, we decompose the resulting DWT matrix using QR and singular value decomposition (SVD). To enhance the system\'s security and robustness, we introduce a modified version of Henon\'s 2D chaotic map. Finally, we integrate the arithmetic optimization algorithm to ensure dynamic and adaptive watermark insertion. Our experimental results demonstrate that our approach outperforms current color image watermarking methods in security, storage capacity, and resistance to various attacks, while maintaining a high level of invisibility.
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  • 文章类型: Journal Article
    干湿循环会导致压实黄土的严重恶化,从而影响填方边坡的安全性。离散元方法(DEM)可以考虑非均匀、不连续,和岩土介质的各向异性性质,更能够反映边坡稳定性分析中失稳的机理和过程。因此,本文提出利用DEM分析干湿循环条件下压实黄土边坡的稳定性。首先,为了解决DEM模型中宏观和介观参数之间复杂的校准问题,通过引入基于sigmoid加速系数的混沌粒子群算法(CPSOS),提出了一种高效的参数优化方法。其次,在参数校准期间,一个新的指标,粘结比(BR),提出了表征干湿循环过程中压实黄土中孔隙和裂缝的发展,以反映干湿作用对黄土骨料间粘结降解的影响。最后,根据参数校准的结果,建立了干湿循环作用下压实黄土边坡的稳定性分析模型。结果表明,所提出的优化标定方法能够准确反映干湿循环下实际试验结果的应力-应变曲线和强度的变化趋势,BR也反映了干湿循环对压实黄土的降解作用。边坡稳定性分析表明,DEM反映了干湿循环对压实黄土边坡安全系数的负面影响,以及干湿循环逐渐稳定的趋势。通过与有限元分析结果的对比,验证了离散元边坡稳定性分析的准确性。
    Dry-wet cycles can cause significant deterioration of compacted loess and thus affect the safety of fill slopes. The discrete element method (DEM) can take into account the non-homogeneous, discontinuous, and anisotropic nature of the geotechnical medium, which is more capable of reflecting the mechanism and process of instability in slope stability analysis. Therefore, this paper proposes to use the DEM to analyze the stability of compacted loess slopes under dry-wet cycles. Firstly, to solve the complex calibration problem between macro and mesoscopic parameters in DEM models, an efficient parameter optimization method was proposed by introducing the chaotic particle swarm optimization with sigmoid-based acceleration coefficients algorithm (CPSOS). Secondly, during the parameter calibration, a new indicator, the bonding ratio (BR), was proposed to characterize the development of pores and cracks in compacted loess during dry-wet cycles, to reflect the impact of dry-wet action on the degradation of bonding between loess aggregates. Finally, according to the results of parameter calibration, the stability analysis model of compacted loess slope under dry-wet cycling was established. The results show that the proposed optimization calibration method can accurately reflect the trend of the stress-strain curve and strength of the actual test results under dry-wet cycles, and the BR also reflects the degradation effect of dry-wet cycles on compacted loess. The slope stability analysis shows that the DEM reflects the negative effect of dry-wet cycles on the safety factor of compacted loess slopes, as well as the trend of gradual stabilization with dry-wet cycles. The comparison with the finite element analysis results verified the accuracy of the discrete element slope stability analysis.
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  • 文章类型: Journal Article
    COVID-19的全球传播深刻影响了健康和经济,强调需要对有效的干预措施进行精确的流行趋势预测。在这项研究中,我们使用传染病模型来模拟和预测COVID-19的轨迹。SEIR(易感,暴露,感染,删除)使用武汉数据建立模型来反映疫情。然后,我们使用来自特定美国地区的数据训练了基于遗传算法的SEIR(GA-SEIR)模型,并专注于个体易感性和感染动力学。通过整合社会心理因素,我们实现了对GA-SEIR模型的显著增强,导致优化版本的开发。这种完善的GA-SEIR模型显著提高了我们模拟疫情传播和控制以及有效跟踪趋势的能力。值得注意的是,它成功预测了2023年4月COVID-19在中国大陆的死灰复燃,证明了其稳健性和可靠性。完善的GA-SEIR模型为公共卫生当局提供了重要的见解,使他们能够设计和实施积极的策略来遏制和缓解疫情。它对流行病建模和公共卫生规划的重大贡献是无价的,特别是在管理和控制呼吸道传染病如COVID-19方面。
    The global spread of COVID-19 has profoundly affected health and economies, highlighting the need for precise epidemic trend predictions for effective interventions. In this study, we used infectious disease models to simulate and predict the trajectory of COVID-19. An SEIR (susceptible, exposed, infected, removed) model was established using Wuhan data to reflect the pandemic. We then trained a genetic algorithm-based SEIR (GA-SEIR) model using data from a specific U.S. region and focused on individual susceptibility and infection dynamics. By integrating socio-psychological factors, we achieved a significant enhancement to the GA-SEIR model, leading to the development of an optimized version. This refined GA-SEIR model significantly improved our ability to simulate the spread and control of the epidemic and to effectively track trends. Remarkably, it successfully predicted the resurgence of COVID-19 in mainland China in April 2023, demonstrating its robustness and reliability. The refined GA-SEIR model provides crucial insights for public health authorities, enabling them to design and implement proactive strategies for outbreak containment and mitigation. Its substantial contributions to epidemic modelling and public health planning are invaluable, particularly in managing and controlling respiratory infectious diseases such as COVID-19.
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  • 文章类型: Journal Article
    这项研究检查了Buea住宅应用的自主混合可再生能源系统(HRES)的最佳尺寸,位于喀麦隆西南部地区。两个混合动力系统,光伏电池和光伏电池柴油,已经进行了评估,以确定哪个是更好的选择。这项研究的目的是提出一个可靠的,低成本电源作为布埃亚不可靠和高度不稳定电网的替代方案。提议的HRES的决策标准是能源成本(COE),而系统的可靠性约束是电源损失概率(LPSP)。小龙虾优化算法(COA)用于优化所提出的HRES的组件尺寸,并将结果与鲸鱼优化算法(WOA)获得的结果进行了对比,正弦余弦算法(SCA),和蝗虫优化算法(GOA)。利用MATLAB软件对组件进行建模,标准,和约束这个单目标优化问题。对小于1%的LPSP进行仿真后获得的结果表明,COA算法优于其他三种技术,无论配置如何。的确,使用COA算法获得的COE为0.06%,0.12%,比WOA提供的COE低1%,SCA,和GOA算法,分别,对于PV电池配置。同样,对于PV-电池-柴油配置,使用COA算法获得的COE为0.065%,0.13%,比WOA提供的COE低0.39%,SCA,和GOA算法,分别。对两种配置获得的结果的比较分析表明,与PV电池配置相比,PV电池柴油配置的COE降低了4.32%。最后,在PV-电池-柴油配置中评估了LPSP降低对COE的影响。由于柴油发电机的标称容量,LPSP的减少导致COE的增加。
    This study examined the optimal size of an autonomous hybrid renewable energy system (HRES) for a residential application in Buea, located in the southwest region of Cameroon. Two hybrid systems, PV-Battery and PV-Battery-Diesel, have been evaluated in order to determine which was the better option. The goal of this research was to propose a dependable, low-cost power source as an alternative to the unreliable and highly unstable electricity grid in Buea. The decision criterion for the proposed HRES was the cost of energy (COE), while the system\'s dependability constraint was the loss of power supply probability (LPSP). The crayfish optimization algorithm (COA) was used to optimize the component sizes of the proposed HRES, and the results were contrasted to those obtained from the whale optimization algorithm (WOA), sine cosine algorithm (SCA), and grasshopper optimization algorithm (GOA). The MATLAB software was used to model the components, criteria, and constraints of this single-objective optimization problem. The results obtained after simulation for LPSP of less than 1% showed that the COA algorithm outperformed the other three techniques, regardless of the configuration. Indeed, the COE obtained using the COA algorithm was 0.06%, 0.12%, and 1% lower than the COE provided by the WOA, SCA, and GOA algorithms, respectively, for the PV-Battery configuration. Likewise, for the PV-Battery-Diesel configuration, the COE obtained using the COA algorithm was 0.065%, 0.13%, and 0.39% lower than the COE provided by the WOA, SCA, and GOA algorithms, respectively. A comparative analysis of the outcomes obtained for the two configurations indicated that the PV-Battery-Diesel configuration exhibited a COE that was 4.32% lower in comparison to the PV-Battery configuration. Finally, the impact of the LPSP reduction on the COE was assessed in the PV-Battery-Diesel configuration. The decrease in LPSP resulted in an increase in COE owing to the nominal capacity of the diesel generator.
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  • 文章类型: Journal Article
    变压器油中溶解糠醛的准确检测对于实时监测变压器油纸绝缘的老化状态至关重要。尽管无标记表面增强拉曼光谱(SERS)对变压器油中溶解的糠醛具有很高的灵敏度,由于基板一致性差和定量可靠性低,挑战依然存在。在这里,机器学习(ML)算法用于无标记SERS的基板制造和光谱分析。最初,通过实验组合制备了一种高稠度的Ag@Au衬底,粒子群优化神经网络(PSO-NN),粒子群算法和遗传算法的混合策略(HybridPSO-GA)。值得注意的是,提出了一个两步机器学习框架,其运行机制是分类,然后是量化。该框架采用分层建模策略,结合了简单的算法,如核支持向量机(Kernel-SVM),k-最近邻(KNN),等。,在每个集群上独立建立轻量级回归模型,这允许每个模型更有效地专注于拟合其群集中的数据。分类模型达到了100%的准确率,而回归模型的平均相关系数(R2)为0.9953,均方根误差(RMSE)始终低于10-2。因此,这种ML框架是一种快速可靠的检测变压器油中溶解糠醛的方法,即使存在不同的干扰物质,这也可能有其他复杂的混合监测系统的潜力。
    Accurate detection of dissolved furfural in transformer oil is crucial for real-time monitoring of the aging state of transformer oil-paper insulation. While label-free surface-enhanced Raman spectroscopy (SERS) has demonstrated high sensitivity for dissolved furfural in transformer oil, challenges persist due to poor substrate consistency and low quantitative reliability. Herein, machine learning (ML) algorithms were employed in both substrate fabrication and spectral analysis of label-free SERS. Initially, a high-consistency Ag@Au substrate was prepared through a combination of experiments, particle swarm optimization-neural network (PSO-NN), and a hybrid strategy of particle swarm optimization and genetic algorithm (Hybrid PSO-GA). Notably, a two-step ML framework was proposed, whose operational mechanism is classification followed by quantification. The framework adopts a hierarchical modeling strategy, incorporating simple algorithms such as kernel support vector machine (Kernel-SVM), k-nearest neighbors (KNN), etc., to independently establish lightweight regression models on each cluster, which allows each model to focus more effectively on fitting the data within its cluster. The classification model achieved an accuracy of 100%, while the regression models exhibited an average correlation coefficient (R2) of 0.9953 and the root mean square errors (RMSE) consistently below 10-2. Thus, this ML framework emerges as a rapid and reliable method for detecting dissolved furfural in transformer oil, even in the presence of different interfering substances, which may also have potentiality for other complex mixture monitoring systems.
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  • 文章类型: Journal Article
    提出了一种高效的并行带状线(PSL)中紧凑型超宽带多级威尔金森功率分配器的设计方法。为了提高所提出的功率分配器的频率带宽,同时减小其尺寸,隔离分支被修改;也就是说,两个电容器连接到每个隔离支路处的电阻器的两侧。为了有效的设计过程,PSL功率分配器等效地由两个微带功率分配器表示,并推导了设计方程。根据设计方程,利用内部算法来优化确定设计参数,包括线路阻抗,阻力,和每个阶段的电容。例如,设计了三级PSL功率分配器,该功率分配器具有3条λ/4传输线,基频为5GHz。为了验证设计程序的准确性,进行3DEM模拟和测量,结果吻合良好。与传统的三级威尔金森功分器相比,拟议的PSL功率分配器实现了1.16至6.51GHz(139.5%)的更宽频率带宽和207°的传输线长度缩短了23%,同时表现出0.7到1.4dB的插入损耗。
    An efficient design method for a compact and ultra-wideband multi-stage Wilkinson power divider in a parallel stripline (PSL) is proposed. To enhance the frequency bandwidth of the proposed power divider while reducing its size, the isolation branch is modified; that is, two capacitors are connected to both sides of a resistor at each isolation branch. For an efficient design process, the PSL power divider is equivalently represented by two microstrip power dividers, and the design equations are derived. Based on the design equations, an in-house algorithm is utilized to optimally determine the design parameters, including the line impedance, resistance, and capacitance of each stage. For example, a three-stage PSL power divider is designed with three λ/4 transmission lines at a base frequency of 5 GHz. To verify the accuracy of the design procedure, 3D EM simulations and measurements are performed, and the results show good agreement. Compared with the conventional three-stage Wilkinson power divider, the proposed PSL power divider achieves a wider frequency bandwidth of 1.16 to 6.51 GHz (139.5%) and a 23% shorter transmission line length of 207°, while exhibiting an insertion loss of 0.7 to 1.4 dB.
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  • 文章类型: Journal Article
    目的:睡眠不足会导致认知障碍,从而增加发生错误和事故的风险。然而,现有的抵消睡眠不足影响的指南是通用的,并非旨在解决特定于个人的情况,导致次最佳警觉水平。这里,我们开发了一种优化算法,该算法可自动识别睡眠时间表和咖啡因给药策略,以最大程度地减少由于一天中期望时间的睡眠不足而导致的警觉性损害.
    方法:我们结合了以前的算法,分别优化睡眠或咖啡因,以同时确定最佳的睡眠时间表和咖啡因剂量,以最大程度地减少所需时间的机敏性损害。优化算法使用经过充分验证的统一性能模型的预测来估计大量可能解决方案的有效性和生理可行性,并确定最佳解决方案。为了评估优化算法,我们使用它来确定4项研究的最佳睡眠时间表和咖啡因给药策略,这些研究体现了常见的睡眠损失情况,并将使用该算法的建议所实现的预测的警觉性损害减少与遵循美国陆军咖啡因指南所实现的预测的警觉性损害减少进行了比较.
    结果:与原始研究中的警觉性损害水平相比,该算法的建议平均减少了63%的警觉性损害,比美国陆军咖啡因指南提高了24个百分点。
    结论:我们提供了一种优化算法,可以同时确定有效和安全的睡眠时间表和咖啡因给药策略,以最大程度地减少用户指定时间的机敏性损害。
    OBJECTIVE: Sleep loss can cause cognitive impairments that increase the risk of mistakes and accidents. However, existing guidelines to counteract the effects of sleep loss are generic and are not designed to address individual-specific conditions, leading to sub-optimal alertness levels. Here, we developed an optimization algorithm that automatically identifies sleep schedules and caffeine-dosing strategies to minimize alertness impairment due to sleep loss for desired times of the day.
    METHODS: We combined our previous algorithms that separately optimize sleep or caffeine to simultaneously identify the best sleep schedules and caffeine doses that minimize alertness impairment at desired times. The optimization algorithm uses the predictions of the well-validated Unified Model of Performance to estimate the effectiveness and physiological feasibility of a large number of possible solutions and identify the best one. To assess the optimization algorithm, we used it to identify the best sleep schedules and caffeine-dosing strategies for four studies that exemplify common sleep-loss conditions and compared the predicted alertness-impairment reduction achieved by using the algorithm\'s recommendations against that achieved by following the U.S. Army caffeine guidelines.
    RESULTS: Compared to the alertness-impairment levels in the original studies, the algorithm\'s recommendations reduced alertness impairment on average by 63%, an improvement of 24 percentage points over the U.S. Army caffeine guidelines.
    CONCLUSIONS: We provide an optimization algorithm that simultaneously identifies effective and safe sleep schedules and caffeine-dosing strategies to minimize alertness impairment at user-specified times.
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  • 文章类型: Journal Article
    作为全球能源消耗和温室气体排放的重要来源,建筑业因其高碳排放而受到广泛关注。预测其发展趋势对于节能减排至关重要。在本文中,利用2012-2021年中国国家和省级建筑业碳排放数据,采用粒子群优化算法优化的灰色预测模型,再加上新陈代谢算法,预测中国及各省建筑业的碳排放量。结果表明:(1)结合新陈代谢算法的动态灰色预测模型比经典模型具有更好的预测效果,相对误差由5.103%降至0.874%。(2)未来十年中国建筑业的碳排放量将继续上升,但是增长率会下降,间接碳排放的比例继续增加。(3)碳排放存在明显的地区差异,东部地区排放水平较高,但增长较慢。相比之下,西部地区排放水平较低,但增长较快。这些研究为现有的节能减排方法提供了有价值的见解,以及未来的政策改进。
    As a significant source of global energy consumption and greenhouse gas emissions, the construction industry garners widespread attention due to its high carbon emissions. Anticipating its development trends is crucial for energy conservation and emission reduction. In this paper, we utilize the carbon emission data from China\'s national and provincial construction sectors from 2012 to 2021, employ the grey prediction model optimized by the particle swarm optimization algorithm, coupled with a metabolic algorithm, to forecast the carbon emissions of the construction industry across China and its provinces. The results demonstrate that: (1) The dynamic grey prediction model combined with the metabolism algorithm has a better prediction effect than the classical model, and the relative error is reduced from 5.103 % to 0.874 %. (2) The carbon emissions of China\'s construction industry will continue to rise in the next decade, but the growth rate will decrease, and the proportion of indirect carbon emissions continues to increase. (3) There is a marked regional disparity in carbon emissions, with the eastern region exhibiting higher emission levels yet slower growth. In contrast, the western region has lower emission levels but experiences faster growth. These studies provide valuable insights for both the existing approaches to energy conservation and emission reduction, as well as for future policy improvements.
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  • 文章类型: Journal Article
    本文提出了一种基于可工业化工业物联网(I3oT)的地板车间压力机中降低能耗的框架。I3oT建议使用系统中可用的信息开发IIoT工具,无需添加任何额外的传感器。基于这种哲学,我们在以前的工作中建议开发C360标准,它允许提取冲压机中可用的所有信息,以开发I3oT应用程序。在这篇文章中,我们建议开发一个框架,以优化从C360标准获得的参数,以在冲压过程中节能。关于可以修改并影响能耗的三个参数,也就是说,平衡压力,吨位和压力速度,我们将在本文中使用前两个。在文章的最后,根据调整结果,显示了安装在福特工厂Almussafes(瓦伦西亚)的压力机的结果。
    This article presents a framework to reduce energy consumption in a floor shop press based on Industrializable Industrial Internet of Things (I3oT). The I3oT proposes the development of IIoT tools using the information available in the system, without adding any additional sensors. Based on this philosophy, we proposed to develop the C360 criterion in our previous works, which allowed to extract all the information available in the stamping presses for the development of I3oT applications. In this article, we propose the development of a framework to optimize the parameters accessible from the C360 criterion for energy saving in the stamping process. Regarding the three parameters that can be modified and that affect energy consumption, that is, counterbalance pressure, tonnage and press speed, we will work with the first two in this paper. At the end of the article, the results obtained from the presses installed at Ford factory in Almussafes (Valencia) are shown based on their adjustment.
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