random forest regression

随机森林回归
  • 文章类型: Journal Article
    微生物生态功能是群落组成的新兴属性。对于某些生态功能,这种联系足够牢固,可以使用群落组成来估计生态功能的数量。这里,我们应用随机森林回归模型来比较群落组成和环境数据对细菌生产(BP)的预测性能。使用来自两个独立的长期生态研究站点的数据-南极洲的PalmerLTER和加利福尼亚的StationSPOT-我们发现社区组成是BP的有力预测指标。在独立验证数据上,表现最好的模型实现了0.84的R2和20.2pmolL-1hr-1的RMSE,优于仅基于环境数据的模型(R2=0.32,RMSE=51.4pmolL-1hr-1)。然后我们操作了我们表现最好的模型,估计2015-2020年346个南极样本的BP,这些样本只有社区组成数据可用。我们的预测解决了BP的空间趋势,在南极具有重要意义(P值=1x10-4),并强调了整个海洋盆地BP的重要分类单元。我们的研究结果表明,微生物群落组成和微生物生态系统功能之间有着密切的联系,并开始利用长期数据集来构建基于微生物群落组成的BP模型。
    Microbial ecological functions are an emergent property of community composition. For some ecological functions this link is strong enough that community composition can be used to estimate the quantity of an ecological function. Here, we apply random forest regression models to compare the predictive performance of community composition and environmental data for bacterial production (BP). Using data from two independent long-term ecological research sites - Palmer LTER in Antarctica and Station SPOT in California - we found that community composition was a strong predictor of BP. The top performing model achieved an R2 of 0.84 and RMSE of 20.2 pmol L-1 hr-1 on independent validation data, outperforming a model based solely on environmental data (R2 = 0.32, RMSE = 51.4 pmol L-1 hr-1). We then operationalized our top performing model, estimating BP for 346 Antarctic samples from 2015-2020 for which only community composition data were available. Our predictions resolved spatial trends in BP with significance in the Antarctic (P value = 1 x 10-4) and highlighted important taxa for BP across ocean basins. Our results demonstrate a strong link between microbial community composition and microbial ecosystem function and begin to leverage long-term datasets to construct models of BP based on microbial community composition.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    在这次调查中,我们在均匀的实验设置下,对Fe(VI)对16种咪唑离子液体变体的氧化进行了详细分析,从而确保二阶反应速率常数(kobs)的数据集。与合并来自不同研究的不同数据的传统方法相比,该方法可确保优越的数据一致性和可比性。利用通过密度泛函理论(DFT)获得的16个化学结构参数作为描述符,建立了定量构效关系(QSAR)模型。通过严格的相关分析,主成分分析(PCA),多元线性回归(MLR),和适用性领域(AD)评估,我们发现分子轨道间隙能量(Egap)和kobs之间存在明显的负相关。MLR分析进一步强调了Egap是一个关键的预测变量,其较低的值表明离子液体中对Fe(VI)的氧化反应性增强,引导QSAR模型实现0.95的预测精度。此外,我们集成了一种先进的机器学习方法-随机森林回归(RFR),通过详尽的决策树,突出了影响咪唑离子液体Fe(VI)氧化效率的关键因素,特征重要性评估,递归特征消除(RFE),和交叉验证策略。RFR模型显示出0.98的显著预测性能。QSAR和RFR模型都指出Egap是显著影响氧化效率的关键描述符,RFR模型呈现较低的均方根误差,将其确立为更可靠的预测工具。RFR模型在本研究中的应用显著提高了模型的稳定性和关键影响因素的直观显示,将有前途的先进分析工具引入环境化学领域。
    In this investigation, we conducted a detailed analysis of the oxidation of 16 imidazole ionic liquid variants by Fe(VI) under uniform experimental setups, thereby securing a dataset of second-order reaction rate constants (kobs). This methodology ensures superior data consistency and comparability over traditional methods that amalgamate disparate data from varied studies. Utilizing 16 chemical structural parameters obtained via Density Functional Theory (DFT) as descriptors, we developed a Quantitative Structure Activity Relationship (QSAR) model. Through rigorous correlation analysis, Principal Component Analysis (PCA), Multiple Linear Regression (MLR), and Applicability Domain (AD) evaluation, we identified a pronounced negative correlation between the molecular orbital gap energy (Egap) and kobs. MLR analysis further underscored Egap as a pivotal predictive variable, with its lower values indicating heightened oxidative reactivity towards Fe(VI) in the ionic liquids, leading the QSAR model to achieve a predictive accuracy of 0.95. Furthermore, we integrated an advanced machine learning approach - Random Forest Regression (RFR), which adeptly highlighted the critical factors influencing the oxidation efficiency of imidazole ionic liquids by Fe(VI) through elaborate decision trees, feature importance assessment, Recursive Feature Elimination (RFE), and cross-validation strategies. The RFR model demonstrated a remarkable predictive performance of 0.98. Both QSAR and RFR models pinpointed Egap as a key descriptor significantly affecting oxidation efficiency, with the RFR model presenting lower root mean square errors, establishing it as a more reliable predictive tool. The application of the RFR model in this study significantly improved the model\'s stability and the intuitive display of key influencing factors, introducing promising advanced analytical tools to the field of environmental chemistry.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    可再生微电网增强安全性,可靠性,通过整合太阳能和风能来提高电力系统的电能质量,减少温室气体排放。本文提出了一种机器学习方法,利用高斯过程(GP)和磷虾群算法(KHA),用于可再生微电网的能源管理,具有基于领带和分段远程切换的可重构结构。该方法利用高斯过程(GP)对混合动力电动汽车(HEV)充电需求进行建模。为抵消HEV充电效应,探索了两种场景:协调充电和智能充电。针对复杂问题,引入了一种受磷虾群算法(KHA)启发的新颖优化方法,以及自适应修改,以根据具体情况定制解决方案。IEEE微电网上的仿真证明了两种情况下的效率。对于总的HEV充电需求,预测模型产生非常低的平均绝对百分比误差(MAPE)1.02381。结果还表明,与协调充电相比,智能充电方案中的微电网运营成本降低。
    Renewable microgrids enhance security, reliability, and power quality in power systems by integrating solar and wind sources, reducing greenhouse gas emissions. This paper proposes a machine learning approach, leveraging Gaussian Process (GP) and Krill Herd Algorithm (KHA), for energy management in renewable microgrids with a reconfigurable structure based on remote switching of tie and sectionalizing. The method utilizes Gaussian Process (GP) for modeling hybrid electric vehicle (HEV) charging demand. To counteract HEV charging effects, two scenarios are explored: coordinated and intelligent charging. A novel optimization method inspired by the Krill Herd Algorithm (KHA) is introduced for the complex problem, along with a self-adaptive modification to tailor solutions to specific situations. Simulation on an IEEE microgrid demonstrates efficiency in both scenarios. The predictive model yields a remarkably low Mean Absolute Percentage Error (MAPE) of 1.02381 for total HEV charging demand. Results also reveal a reduction in microgrid operation cost in the intelligent charging scenario compared to coordinated charging.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    在这项工作中,我们提出了一种利用混合深度学习方法的光倍频方法,该方法将残差网络(ResNet)与随机森林回归(RFR)算法集成在一起。采用三种不同的倍频调制方案来说明该方法,这可以为这些方案获得合适的参数。根据算法预测的参数,8-tupling,12元组,并通过数值模拟产生16倍频毫米波信号。仿真结果表明,对于8倍倍频,OSSR(光边带抑制比)为30.73dB,80GHz的RFSSR(射频杂散抑制比)为42.29dB。对于12倍倍频乘法,OSSR为30.09dB,120GHz毫米波的RFSSR为36.21dB。为了产生16倍频毫米波,获得29.86dB的OSSR和34.52dB的RFSSR。此外,还研究了幅度波动和偏置电压漂移对毫米波信号质量的影响。
    In this work, we present a method for optical frequency multiplication utilizing a hybrid deep learning approach that integrates the Residual Network (ResNet) with the Random Forest Regression (RFR) algorithm. Three different frequency multiplication modulation schemes are adopted to illustrate the method, which can obtain suitable parameters for these schemes. Based on the parameters predicted by the algorithm, the 8-tupling, 12-tupling, and 16-tupling mm-wave signals are generated by numerical simulation. The simulation results show that for 8-tupling frequency multiplication, an OSSR (optical sideband suppression ratio) is 30.73 dB and an RFSSR (radio frequency spurious suppression ratio) of 80 GHz is 42.29 dB. For 12-tupling frequency multiplication, the OSSR is 30.09 dB, and the RFSSR of the 120 GHz mm wave is 36.21 dB. For generating 16-tupling frequency mm-wave, an OSSR of 29.86 dB and an RFSSR of 34.52 dB are obtained. In addition, the impact of amplitude fluctuation and bias voltage drift on the quality of mm-wave signals is also studied.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    城市公园在UHI缓解中起着关键作用。然而,其他突出类型的城市绿色基础设施的作用尚未得到全面研究。因此,这项研究的主要目的是评估与经过充分研究的公园地区相比,墓地和分配区作为冷却岛的作用。我们评估了墓地的LST,夏季,根据Landsat8TM图像在德国五个最大城市的分配和公园。随机森林回归用光谱指数(NDVI,Ndmi,NDBaI)以及具有树木特征(树木类型,树龄,树干圆周,树干高度或树冠密度)。因此,分配被确定为最热的UGS,城市平均值在23.1和26.9°C之间变化,因为它们含有相对高比例的密封表面。NDVI最好地解释了分配花园的LST空间变异性,这表明开花灌木和树木比例较高的田地显示出比一年生作物覆盖的LST值低的LST值。有趣的是,墓地被称为最酷的UGS,与城市之间的意思是20.4和24.7°C。尽管它们的密封表面比例很高,它们以老树为主,导致密集的蒸腾过程。公园显示出异质的LST模式,由于公园功能和形状的可变性,光谱指数无法系统地解释这些模式。与公园相比,墓地的树木覆盖区域具有更高的降温潜力,因为墓地作为文化遗产得到了很好的保护,允许老树生长和密集的蒸腾作用。这些发现强调了墓地作为冷却岛的相关性,并加深了对树木特征在冷却过程中的作用的理解。
    Urban parks play a key role in UHI mitigation. However, the role of other prominent types of urban green infrastructure has not been comprehensively studied. Thus, the main objective of this study was to evaluate the role of cemeteries and allotments as cooling islands compared to the well-studied park areas. We assessed the LST of cemeteries, allotments and parks based on Landsat 8 TM images across the five largest German cities during summertime. Random forest regressions explain the LST spatial variability of the different urban green spaces (UGS) with spectral indices (NDVI, NDMI, NDBaI) as well as with tree characteristics (tree type, tree age, trunk circumferences, trunk height or canopy density). As a result, allotments were identified as the hottest UGS with the city means varying between 23.1 and 26.9 °C, since they contain a relatively high proportion of sealed surfaces. The LST spatial variability of allotment gardens was best explained by the NDVI indicating that fields with a higher percentage of flowering shrubs and trees reveal lower LST values than those covered by annual crops. Interestingly, cemeteries were characterized as the coolest UGS, with city means between 20.4 and 24.7 °C. Despite their high proportion of sealed surfaces, they are dominated by old trees resulting in intensive transpiration processes. Parks show heterogeneous LST patterns which could not be systematically explained by spectral indices due to the variability of park functionality and shape. Compared to parks, the tree-covered areas of cemeteries have a higher cooling potential since cemeteries as cultural heritage sites are well-protected allowing old tree growth with intensive transpiration. These findings underline the relevance of cemeteries as cooling islands and deepen the understanding of the role of tree characteristics in the cooling process.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    气候变化和人类活动对土壤流失和土壤保持服务产生了显著影响,对区域生态可持续性构成了威胁。然而,潜在土壤流失之间的关系和潜在的驱动力,实际土壤流失,和水土保持服务还没有得到很好的理解。利用生态系统服务和权衡综合评估(InVEST)模型,我们评估了1990年至2020年青藏高原的土壤保护服务。我们分析了时空趋势,并使用线性回归检查了驱动因素,皮尔逊相关性,和随机森林回归。土壤保持服务表现出复杂的模式,增加后减少,2010年左右的转折点。土壤保持服务和土壤流失表现出非权衡变化。潜在的土壤流失主导了青藏高原土壤保持服务的时空格局。气候因子显著影响土壤保持服务的时空格局,随着年降水量成为主要驱动因素,贡献约20%。然而,2010年以来人类活动的影响越来越明显,植被对土壤保持服务变化的贡献增加。归一化植被指数(NDVI)对一级土壤保持服务的影响,II,和III增加了13.19%,3.08%,和3.41%,分别。相反,在2010年之前的西藏北部和2010年之后的东三江源,土壤保持服务表现出在气候因素和人类活动共同驱动下的增长趋势。表明生态修复措施的实施促进了植被的改善,减少了实际土壤流失。本研究为资源管理提供了科学依据,土地开发战略,以及制定青藏高原生态修复措施。
    Climate change and human activities have significantly influenced soil loss and the soil conservation service, posed threats to regional ecological sustainability. However, the relationships and underlying driving forces between potential soil loss, actual soil loss, and soil conservation service have not been well understood. Utilizing the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model, we evaluated the soil conservation service on the Tibetan plateau from 1990 to 2020. We analyzed the spatial and temporal trends and examined the driving factors using linear regression, Pearson correlation, and random forest regression. The soil conservation service exhibited a complex pattern of increase followed by a decrease, with a turning point around 2010. Soil conservation service and soil loss demonstrated non-trade-off changes. The potential soil loss dominated the spatiotemporal patterns of soil conservation service on the Tibetan Plateau. Climatic factors significantly influenced the spatiotemporal patterns of soil conservation service, with annual precipitation emerging as the dominant driving factor, contributing approximately 20%. However, the impacts of human activities became more pronounced since 2010, and the contribution of vegetation to changes in soil conservation service was increased. The impact of the Normalized Difference Vegetation Index (NDVI) on soil conservation service for the grades I, II, and III increased by 13.19%, 3.08%, and 3.41%, respectively. Conversely, in northern Tibet before 2010 and eastern Three-River-Source after 2010, soil conservation service exhibited an increasing trend driven by both climate factors and human activities. Which indicates that the implementation of ecological restoration measures facilitated vegetation improvement and subsequently reduced actual soil loss. This study provides a scientific basis for resource management, land development strategies, and the formulation of ecological restoration measures on the Tibetan Plateau.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    在气候变化的背景下,监测植物生理参数的时空变异变得越来越重要。远程光谱成像和GIS软件已在制图领域的变化方面显示出有效性。此外,机器学习技术的应用,对于处理大数据量至关重要,农业应用显着增加。这项研究的重点是角豆树,一种在地中海盆地传播的抗旱树木作物。该研究旨在开发可靠的模型来预测角豆树的净同化和气孔导度,并使用这些模型来分析季节变化和不同灌溉系统的影响。
    行星卫星图像是在现场数据测量当天获取的。行星光谱带的反射率值被用作预测因子来开发模型。这项研究采用了随机森林建模方法,并将其性能与传统的多元线性回归进行了比较。
    研究结果表明,随机森林,利用行星光谱带作为预测因子,在预测净同化(R²=0.81)和气孔导度(R²=0.70)方面取得了很高的准确性,黄色和红色光谱区域特别有影响力。此外,研究表明,各种灌溉系统和雨养条件之间的内在水分利用效率没有显着差异。这项工作强调了在精准农业中结合卫星遥感和机器学习的潜力,目的是有效监测生理参数。
    UNASSIGNED: In the context of climate change, monitoring the spatial and temporal variability of plant physiological parameters has become increasingly important. Remote spectral imaging and GIS software have shown effectiveness in mapping field variability. Additionally, the application of machine learning techniques, essential for processing large data volumes, has seen a significant rise in agricultural applications. This research was focused on carob tree, a drought-resistant tree crop spread through the Mediterranean basin. The study aimed to develop robust models to predict the net assimilation and stomatal conductance of carob trees and to use these models to analyze seasonal variability and the impact of different irrigation systems.
    UNASSIGNED: Planet satellite images were acquired on the day of field data measurement. The reflectance values of Planet spectral bands were used as predictors to develop the models. The study employed the Random Forest modeling approach, and its performances were compared with that of traditional multiple linear regression.
    UNASSIGNED: The findings reveal that Random Forest, utilizing Planet spectral bands as predictors, achieved high accuracy in predicting net assimilation (R² = 0.81) and stomatal conductance (R² = 0.70), with the yellow and red spectral regions being particularly influential. Furthermore, the research indicates no significant difference in intrinsic water use efficiency between the various irrigation systems and rainfed conditions. This work highlighted the potential of combining satellite remote sensing and machine learning in precision agriculture, with the goal of the efficient monitoring of physiological parameters.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    在快速发展的蒸汽侵入(VI)评估领域,传统方法包括详细的地下水和土壤蒸气采样以及全面的实验室测量。这些模型,混合经验数据,理论方程,和特定于站点的参数,通过考虑一系列影响因素来评估VI风险,从地下水中的挥发性有机化合物(VOC)浓度到细微的土壤属性。然而,可变性的挑战,受动态环境条件和复杂土壤特性的影响,remains.我们的研究提出了一种先进的现场气体传感站,旨在实时监测VOC通量,丰富了一系列环境传感器,并以可靠的PID传感器为先导,用于VOC检测。将这个动态系统与机器学习集成,我们开发了预测模型,特别是随机森林回归,其R平方值超过79%,平均相对误差接近0.25,证实了其准确预测土壤蒸气中三氯乙烯(TCE)浓度的能力。通过协同实时监控和预测洞察,我们的方法完善了VI风险评估,为社区提供积极主动的装备,明智的决策工具和加强环境安全。实施这些预测模型可以简化对居民的监控,减少对专业系统的依赖。一旦证明有效,有可能将监测站重新用于其他VI易发地区,扩大他们的影响力和利益。开发的模型可以利用天气预报数据来预测和提供未来VOC事件的警报。
    In the rapidly evolving domain of vapor intrusion (VI) assessments, traditional methodologies encompass detailed groundwater and soil vapor sampling coupled with comprehensive laboratory measurements. These models, blending empirical data, theoretical equations, and site-specific parameters, evaluate VI risks by considering a spectrum of influential factors, from volatile organic compounds (VOC) concentrations in groundwater to nuanced soil attributes. However, the challenge of variability, influenced by dynamic ambient conditions and intricate soil properties, remains. Our study presents an advanced on-site gas sensing station geared towards real-time VOC flux monitoring, enriched with an array of ambient sensors, and spearheaded by the reliable PID sensor for VOC detection. Integrating this dynamic system with machine learning, we developed predictive models, notably the random forest regression, which boasts an R-squared value exceeding 79 % and mean relative error near 0.25, affirming its capability to predict trichloroethylene (TCE) concentrations in soil vapor accurately. By synergizing real-time monitoring and predictive insights, our methodology refines VI risk assessments, equipping communities with proactive, informed decision-making tools and bolstering environmental safety. Implementing these predictive models can simplify monitoring for residents, reducing dependence on specialized systems. Once proven effective, there\'s potential to repurpose monitoring stations to other VI-prone regions, expanding their reach and benefit. The developed model can leverage weather forecasting data to predict and provide alerts for future VOC events.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    理解主观情感体验与生理信号之间的关联具有现实意义和理论意义。先前的心理生理学研究表明,动态情绪效价体验与面部肌电图(EMG)活动之间存在线性关系。然而,主观情绪效价动态是否以及如何与面部肌电图非线性变化相关尚不清楚。为了调查这个问题,我们对之前两项研究的数据进行了重新分析,这些研究测量了来自50名观看情感电影片段的参与者的皱褶上肌和颧骨主要肌的动态效价评分和面部肌电图.我们采用了多元线性回归分析和两个非线性机器学习(ML)模型:随机森林和长期短期记忆。在交叉验证中,这些ML模型在均方误差和相关系数方面优于线性回归.使用SHapley加法扩展工具对随机森林模型的解释揭示了几个EMG特征与主观效价动力学之间的非线性和交互关联。这些发现表明,与传统的线性模型相比,非线性ML模型可以更好地拟合主观情绪效价动态与面部肌电图之间的关系,并突出了非线性和复杂的关系。这些发现鼓励使用面部肌电图进行情绪感知,并提供对主观生理关联的洞察力。
    Understanding the association between subjective emotional experiences and physiological signals is of practical and theoretical significance. Previous psychophysiological studies have shown a linear relationship between dynamic emotional valence experiences and facial electromyography (EMG) activities. However, whether and how subjective emotional valence dynamics relate to facial EMG changes nonlinearly remains unknown. To investigate this issue, we re-analyzed the data of two previous studies that measured dynamic valence ratings and facial EMG of the corrugator supercilii and zygomatic major muscles from 50 participants who viewed emotional film clips. We employed multilinear regression analyses and two nonlinear machine learning (ML) models: random forest and long short-term memory. In cross-validation, these ML models outperformed linear regression in terms of the mean squared error and correlation coefficient. Interpretation of the random forest model using the SHapley Additive exPlanation tool revealed nonlinear and interactive associations between several EMG features and subjective valence dynamics. These findings suggest that nonlinear ML models can better fit the relationship between subjective emotional valence dynamics and facial EMG than conventional linear models and highlight a nonlinear and complex relationship. The findings encourage emotion sensing using facial EMG and offer insight into the subjective-physiological association.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    这项研究的目的是分析未来气候变化对布基纳法索草地覆盖的潜在影响。MODISNDVI250m时间序列用于监测2000-2022年草地的变化。通过将草地覆盖的参考数据与当前的气候和其他环境预测因子进行回归来拟合随机森林回归(RFR)模型,以预测当前的草地覆盖图(2022)。在SSP126和SSP585情景下使用的CMIP6的预测气候模型数据被集成到拟合RFR模型中,以预测未来的变化。结果表明,在2000-2022年期间,草地面积主要由非显着生产力变化(55%)主导。在这个时期,草地面积知道生产力增加(35%)多于减少(10%)。在SSP126和SSP585情景下,预计到2061-2080年,布基纳法索将面临更多的草地覆盖面积减少,而不是增加。这项研究的结果可以帮助制定适当的适应措施,以应对布基纳法索的气候变化。
    The objective of this study was to analyse the potential impact of future climate change on grassland cover in Burkina Faso. MODIS NDVI 250 m time series were used to monitor changes in grassland over 2000-2022. The random forest regression (RFR) model was fit by regressing reference data of grassland cover against current climatic and other environmental predictors to predict the current grassland cover map (2022). Projected climate model data of CMIP6 used under SSP 126 and SSP 585 scenarios were integrated into the fit RFR model to predict future change. The results revealed that grassland areas were largely dominated by non-significant productivity change (55%) during 2000-2022. In this period, grassland area knew more increased productivity (35%) than decrease (10%). Burkina Faso is predicted to face more decreased areas of grassland cover than increase by 2061-2080 under SSP 126 and SSP 585 scenarios. The findings of this study can help to set up appropriate adaptation measures to combat climate change in Burkina Faso.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

公众号