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Developing Hybrid XGBoost Model to Predict the Strength of Polypropylene and Straw Fibers Reinforced Cemented Paste Backfill and Interpretability Insights
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作者 Yingui Qiu Enming Li +2 位作者 Pablo Segarra Bin Xi Jian Zhou 《Computer Modeling in Engineering & Sciences》 2025年第8期1607-1629,共23页
With the growing demand for sustainable development in the mining industry,cemented paste backfill(CPB)materials,primarily composed of tailings,play a crucial role in mine backfilling and underground support systems.T... With the growing demand for sustainable development in the mining industry,cemented paste backfill(CPB)materials,primarily composed of tailings,play a crucial role in mine backfilling and underground support systems.To enhance the mechanical properties of CPB materials,fiber reinforcement technology has gradually gained attention,though challenges remain in predicting its performance.This study develops a hybrid model based on the adaptive equilibrium optimizer(adap-EO)-enhanced XGBoost method for accurately predicting the uniaxial compressive strength of fiber-reinforced CPB.Through systematic comparison with various other machine learning methods,results demonstrate that the proposed hybridmodel exhibits excellent predictive performance on the test set,achieving a coefficient of determination(R^(2))of 0.9675,root mean square error(RMSE)of 0.6084,and mean absolute error(MAE)of 0.4620.Input importance analysis reveals that cement-tailings ratio,curing time,and concentration are the three most critical factors affectingmaterial strength,with cement-tailings ratio showing a positive correlation with strength,concentrations above 70% significantly improvingmaterial strength,and curing periods beyond 28 days being essential for strength development.Fiber parameters contribute secondarily but notably to material strength,with fiber length exhibiting an optimal range of approximately 12 mm.This study not only provides a high-precision strength prediction model but also reveals the inherent correlations between various parameters and material performance,offering scientific basis for mixture optimization and engineering applications of fiber-reinforced CPB materials. 展开更多
关键词 Cemented paste backfill fiber-enhanced compressive strength prediction XGBoost adap-EO algorithm SHAP
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Strength prediction and cuttability identification of rock based on monitoring while cutting(MWC)using a conical pick
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作者 Shaofeng Wang Yumeng Wu +2 位作者 Xinlei Shi Xin Cai Zilong Zhou 《International Journal of Minerals,Metallurgy and Materials》 2025年第5期1025-1043,共19页
Real-time identification of rock strength and cuttability based on monitoring while cutting during excavation is essential for key procedures such as the precise adjustment of excavation parameters and the in-situ mod... Real-time identification of rock strength and cuttability based on monitoring while cutting during excavation is essential for key procedures such as the precise adjustment of excavation parameters and the in-situ modification of hard rocks.This study proposes an in-telligent approach for predicting rock strength and cuttability.A database comprising 132 data sets is established,containing cutting para-meters(such as cutting depth and pick angle),cutting responses(such as specific energy and instantaneous cutting rate),and rock mech-anical parameters collected from conical pick-cutting experiments.These parameters serve as input features for predicting the uniaxial compressive strength and tensile strength of rocks using regression fitting and machine learning methodologies.In addition,rock cuttabil-ity is classified using a combination of the analytic hierarchy process and fuzzy comprehensive evaluation method,and subsequently iden-tified through machine learning approaches.Various models are compared to determine the optimal predictive and classification models.The results indicate that the optimal model for uniaxial compressive strength and tensile strength prediction is the genetic algorithm-optimized backpropagation neural network model,and the optimal model for rock cuttability classification is the radial basis neural network model. 展开更多
关键词 conical picks strength prediction cuttability identification machine learning monitoring while cutting
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Prediction on rock strength by mineral composition from machine learning of ECS logs
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作者 Dongwen Li Xinlong Li +5 位作者 Li Liu Wenhao He Yongxin Li Shuowen Li Huaizhong Shi Gaojian Fan 《Energy Geoscience》 2025年第2期207-222,共16页
Rock strength evaluation is critical in oil and gas exploration,but traditional methods,such as empirical formulas,laboratory tests,and numerical simulations,often struggle with accuracy,generalizability,and alignment... Rock strength evaluation is critical in oil and gas exploration,but traditional methods,such as empirical formulas,laboratory tests,and numerical simulations,often struggle with accuracy,generalizability,and alignment with field conditions.This study proposes the use of Random Forest and Transformer algorithms to predict rock strength from Elemental Capture Spectroscopy(ECS)logs.By utilizing the dry weight of minerals as input,the model predicts key mechanical properties,including Young's modulus,Poisson's ratio,bulk modulus,shear modulus,and uniaxial compressive strength.The findings demonstrate that mineral compositions,such as clay,quartz-feldspar-mica,carbonate,anhydrite,and pyrite,significantly influence rock strength.Specifically,clay content impacts Young's modulus,bulk modulus,and shear modulus,while quartz-feldspar-mica affects Poisson's ratio,and anhydrite is the primary factor influencing compressive strength.Positive correlations were observed between rock strength and the dry weight of anhydrite and carbonate minerals,while negative correlations emerged with clay,pyrite,and quartz-feldspar-mica.The Random Forest model outperformed the Transformer model in terms of predictive accuracy and computational efficiency.Its training time is only one three hundredth of the latter and its prediction time is just one tenth of the later,making it highly suitable for welllogging interpretation.Although the Transformer model was less computationally efficient,it exhibited strengths in predicting subsurface strength parameters,particularly in capturing spatial variations and forecasting these parameters across different spatial locations.This study introduces a novel AI-driven approach to rock strength evaluation,bridging the gap between mineral composition and mechanical properties,with significant implications for resource extraction and reservoir management. 展开更多
关键词 Elemental capture spectroscopy(ECS) Rock strength prediction Mineral composition Random forest Transformer
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Predicting Concrete Strength Using Data Augmentation Coupled with Multiple Optimizers in Feedforward Neural Networks
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作者 Sandeerah Choudhary Qaisar Abbas +3 位作者 Tallha Akram Irshad Qureshi Mutlaq B.Aldajani Hammad Salahuddin 《Computer Modeling in Engineering & Sciences》 2025年第11期1755-1787,共33页
The increasing demand for sustainable construction practices has led to growing interest in recycled aggregate concrete(RAC)as an eco-friendly alternative to conventional concrete.However,predicting its compressive st... The increasing demand for sustainable construction practices has led to growing interest in recycled aggregate concrete(RAC)as an eco-friendly alternative to conventional concrete.However,predicting its compressive strength remains a challenge due to the variability in recycled materials and mix design parameters.This study presents a robust machine learning framework for predicting the compressive strength of recycled aggregate concrete using feedforward neural networks(FFNN),Random Forest(RF),and XGBoost.A literature-derived dataset of 502 samples was enriched via interpolation-based data augmentation and modeled using five distinct optimization techniques within MATLAB’s Neural Net Fitting module:Bayesian Regularization,Levenberg-Marquardt,and three conjugate gradient variants—Powell/Beale Restarts,Fletcher-Powell,and Polak-Ribiere.Hyperparameter tuning,dropout regularization,and early stopping were employed to enhance generalization.Comparative analysis revealed that FFNN outperformed RF and XGBoost,achieving an R2 of 0.9669.To ensure interpretability,accumulated local effects(ALE)along with partial dependence plots(PDP)were utilized.This revealed trends consistent with the pre-existent domain knowledge.This allows estimation of strength from the properties of the mix without extensive lab testing,permitting designers to track the performance and sustainability trends in concrete mix designs while promoting responsible construction and demolition waste utilization. 展开更多
关键词 Feedforward neural networks recycled aggregates compressive strength prediction optimization techniques data augmentation grid search
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Explainable artificial intelligence model for the prediction of undrained shear strength
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作者 Ho-Hong-Duy Nguyen Thanh-Nhan Nguyen +3 位作者 Thi-Anh-Thu Phan Ngoc-Thi Huynh Quoc-Dat Huynh Tan-Tai Trieu 《Theoretical & Applied Mechanics Letters》 2025年第3期284-295,共12页
Machine learning(ML)models are widely used for predicting undrained shear strength(USS),but interpretability has been a limitation in various studies.Therefore,this study introduced shapley additive explanations(SHAP)... Machine learning(ML)models are widely used for predicting undrained shear strength(USS),but interpretability has been a limitation in various studies.Therefore,this study introduced shapley additive explanations(SHAP)to clarify the contribution of each input feature in USS prediction.Three ML models,artificial neural network(ANN),extreme gradient boosting(XGBoost),and random forest(RF),were employed,with accuracy evaluated using mean squared error,mean absolute error,and coefficient of determination(R^(2)).The RF achieved the highest performance with an R^(2) of 0.82.SHAP analysis identified pre-consolidation stress as a key contributor to USS prediction.SHAP dependence plots reveal that the ANN captures smoother,linear feature-output relationships,while the RF handles complex,non-linear interactions more effectively.This suggests a non-linear relationship between USS and input features,with RF outperforming ANN.These findings highlight SHAP’s role in enhancing interpretability and promoting transparency and reliability in ML predictions for geotechnical applications. 展开更多
关键词 prediction of undrained shear strength Explanation model Shapley additive explanation model Explainable AI
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Strength prediction of multi-layered copper-based composites fabricated by accumulative roll bonding 被引量:10
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作者 P.SEIFOLLAHZADEH Morteza ALIZADEH M.R.ABBASI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第6期1729-1739,共11页
This work aims to evaluate the feasibility of the fabrication of nanostructured Cu/Al/Ag multi-layered composites by accumulative roll bonding(ARB),and to analyze the tensile properties and electrical conductivity of ... This work aims to evaluate the feasibility of the fabrication of nanostructured Cu/Al/Ag multi-layered composites by accumulative roll bonding(ARB),and to analyze the tensile properties and electrical conductivity of the produced composites.A theoretical model using strengthening mechanisms and some structural parameters extracted from X-ray diffraction is also developed to predict the tensile strength of the composites.It was found that by progression of ARB,the experimental and calculated tensile strengths are enhanced,reach a maximum of about 450 and 510 MPa at the fifth cycle of ARB,respectively and then are reduced.The electrical conductivity decreased slightly by increasing the number of ARB cycles at initial ARB cycles,but the decrease was intensified at the final ARB cycles.In conclusion,the merit of ARB to fabricate this type of multi-layered nanocomposites and the accuracy of the developed model to predict tensile strength were realized. 展开更多
关键词 multi-layered composites accumulative roll bonding strength prediction HARDNESS X-ray diffraction
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Cubic Meter Compressive Strength Prediction of Concrete 被引量:3
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作者 龚珍 ZHANG Yimin +3 位作者 胡友健 YU Yan YUAN Yanbin LI Hua 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第3期590-593,共4页
In order to improve the prediction accuracy of compressive strength of concrete,103 groups of concrete data were collected as the samples.We selected seven kinds of ingredients from the concrete samples, using Grid-SV... In order to improve the prediction accuracy of compressive strength of concrete,103 groups of concrete data were collected as the samples.We selected seven kinds of ingredients from the concrete samples, using Grid-SVM, PSO-SVM, and GA-SVM models to establish the prediction model of cubic meter compressive strength of concrete.The experimental results show that SVM model based on Grid optimization algorithm,SVM model based on Particle swarm optimization algorithm,SVM model based on Genetic optimization algorithm mean square error respectively are 0.001, 0.489 8, and 0.304 2, correlation coefficients are 0.994 8, 0.994 6, and 0.993 0. It is shown that cubic meter compressive strength prediction method based on Grid-SVM model is the best optimization algorithm. 展开更多
关键词 cubic meter compressive strength prediction PSO-SVM GA-SVM Grid-SVM
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Prediction of Antifrccze Critical Strength of Infant Age Concrete 被引量:2
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作者 LIU Jun LIU Runqing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2008年第2期272-275,共4页
The rule of infant age concrete strength development under low temperature and complex affecting factors is researched. An efficient and reliable mathematical forecast model is set up to predict the infant age concret... The rule of infant age concrete strength development under low temperature and complex affecting factors is researched. An efficient and reliable mathematical forecast model is set up to predict the infant age concrete antifreeze critical strength under low temperature at construction site. On the basis of the revision of concrete equivalent coefficient under complex influencing factors, least-squares curve-fitting method is applied to approximate the concrete strength under standard curing and the forecast formula of concrete compressive strength could be obtained under natural temperature condition by various effects. When the amounts of double-doped are 10% fly ashes and 4% silica fumes as coment replacement, the antifreeze critical strength changes form 3.5-4.1MPa under different low temperature curing. The equivalent coefficient correction formula of concrete under low temperature affected by various factors could be obtained. The obtained equivalent coefficient is suitable for calculating the strength which is between 10% to 40% of standard strength and the curing temperature from 5-20 ℃. The forecast value of concrete antifreeze critical strength under low temperature could be achieved by combining the concrete antifreeze critical strength value with the compressive strength forecast of infant age concrete under low temperature. Then the theory for construction quality control under low temperature is provided. 展开更多
关键词 low temperature concrete infant age equivalent coefficient least-squares curve-fitting strength prediction
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Yield strength prediction of rolled Al-(1.44-12.40)Si-0.7Mg alloy sheets under T4 condition 被引量:3
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作者 Guang-dong WANG Ni TIAN +3 位作者 Jing-yi CAO Yi-ran ZHOU Gang ZHAO Liang ZUO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第8期2045-2055,共11页
The effects of Si content on the microstructure and yield strength of Al-(1.44-12.40)Si-0.7 Mg(wt.%)alloy sheets under the T4 condition were systematically studied via laser scanning confocal microscopy(LSCM),DSC,TEM ... The effects of Si content on the microstructure and yield strength of Al-(1.44-12.40)Si-0.7 Mg(wt.%)alloy sheets under the T4 condition were systematically studied via laser scanning confocal microscopy(LSCM),DSC,TEM and tensile tests.The results show that the recrystallization grain of the alloy sheets becomes more refined with an increase in Si content.When the Si content increases from 1.44 to 12.4 wt.%,the grain size of the alloy sheets decreases from approximately 47 to 10μm.Further,with an increase in Si content,the volume fraction of the GP zones in the matrix increases slightly.Based on the existing model,a yield strength model for alloy sheets was proposed.The predicted results are in good agreement with the actual experimental results and reveal the strengthening mechanisms of the Al-(1.44-12.40)Si-0.7 Mg alloy sheets under the T4 condition and how they are influenced by the Si content. 展开更多
关键词 wrought Al-(1.44-12.40)Si-0.7Mg alloy sheets T4 condition Si content yield strength prediction strengthening mechanism
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Prediction of the residual strength of clay using functional networks 被引量:6
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作者 S.Z.Khan Shakti Suman +1 位作者 M.Pavani S.K.Das 《Geoscience Frontiers》 SCIE CAS CSCD 2016年第1期67-74,共8页
Landslides are common natural hazards occurring in most parts of the world and have considerable adverse economic effects. Residual shear strength of clay is one of the most important factors in the determination of s... Landslides are common natural hazards occurring in most parts of the world and have considerable adverse economic effects. Residual shear strength of clay is one of the most important factors in the determination of stability of slopes or landslides. This effect is more pronounced in sensitive clays which show large changes in shear strength from peak to residual states. This study analyses the prediction of the residual strength of clay based on a new prediction model, functional networks(FN) using data available in the literature. The performance of FN was compared with support vector machine(SVM) and artificial neural network(ANN) based on statistical parameters like correlation coefficient(R), Nash–Sutcliff coefficient of efficiency(E), absolute average error(AAE), maximum average error(MAE) and root mean square error(RMSE). Based on R and E parameters, FN is found to be a better prediction tool than ANN for the given data. However, the R and E values for FN are less than SVM. A prediction equation is presented that can be used by practicing geotechnical engineers. A sensitivity analysis is carried out to ascertain the importance of various inputs in the prediction of the output. 展开更多
关键词 LANDSLIDES Residual strength Index properties prediction model Functional networks
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Uniaxial Compressive Strength Prediction for Rock Material in Deep Mine Using Boosting-Based Machine Learning Methods and Optimization Algorithms
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作者 Junjie Zhao Diyuan Li +1 位作者 Jingtai Jiang Pingkuang Luo 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期275-304,共30页
Traditional laboratory tests for measuring rock uniaxial compressive strength(UCS)are tedious and timeconsuming.There is a pressing need for more effective methods to determine rock UCS,especially in deep mining envir... Traditional laboratory tests for measuring rock uniaxial compressive strength(UCS)are tedious and timeconsuming.There is a pressing need for more effective methods to determine rock UCS,especially in deep mining environments under high in-situ stress.Thus,this study aims to develop an advanced model for predicting the UCS of rockmaterial in deepmining environments by combining three boosting-basedmachine learning methods with four optimization algorithms.For this purpose,the Lead-Zinc mine in Southwest China is considered as the case study.Rock density,P-wave velocity,and point load strength index are used as input variables,and UCS is regarded as the output.Subsequently,twelve hybrid predictive models are obtained.Root mean square error(RMSE),mean absolute error(MAE),coefficient of determination(R2),and the proportion of the mean absolute percentage error less than 20%(A-20)are selected as the evaluation metrics.Experimental results showed that the hybridmodel consisting of the extreme gradient boostingmethod and the artificial bee colony algorithm(XGBoost-ABC)achieved satisfactory results on the training dataset and exhibited the best generalization performance on the testing dataset.The values of R2,A-20,RMSE,and MAE on the training dataset are 0.98,1.0,3.11 MPa,and 2.23MPa,respectively.The highest values of R2 and A-20(0.93 and 0.96),and the smallest RMSE and MAE values of 4.78 MPa and 3.76MPa,are observed on the testing dataset.The proposed hybrid model can be considered a reliable and effective method for predicting rock UCS in deep mines. 展开更多
关键词 Uniaxial compression strength strength prediction machine learning optimization algorithm
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Field strength prediction of mobile communication network based on GIS
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作者 CHEN Xiaoyong WU Hualing Tran Minh TRI 《Geo-Spatial Information Science》 SCIE EI 2012年第3期199-206,共8页
This article describes GIS-based models successfully developed for predicting the coverage of Cityphone cellular network,visualizing the predicted signal strength,and analyzing the field strength coverage.In order to ... This article describes GIS-based models successfully developed for predicting the coverage of Cityphone cellular network,visualizing the predicted signal strength,and analyzing the field strength coverage.In order to predict the signal coverage strength of communication network more accurately,the spatial and nonspatial databases of a mobile cellular network are combined by GIS and produce the necessary parameters.A GIS model named COST-231-Walfisch–Ikegami model(WIM)is developed for signal coverage prediction in Ho Chi Minh City.Radio-line-of-sight and nonradio-lineof-sight conditions can be determined by this model.In addition,in case of nonradio-line-of-sight conditions,average building height,building separation,building width,incident radio path,and road orientation with respect to the direct radio path were obtained using GIS.Road orientation loss,multiscreen diffraction loss,and shadowing gain were predicted more accurate by this model.The scale of maps in the experiment was 1:2000 and the average of floor height was 3 m because there were no exact building height measurements.Statistical results show that the path loss predicted by the COST 231 WIM overcame the real path loss of each cell station.And this method can be used for signal coverage prediction of mobile cellular network in urban areas.Compared to the current situation with the Ho Chi Minh City Posts and Telecommunications system,this model can be effectively applied to improve the Cityphone mobile network quality as well as capability.Developed GIS models can help designers in predicting cell station coverage using real spatial maps that make the results more reliable.This research can help network operators improve the network quality and capability with the best investment efficiently. 展开更多
关键词 mobile communication network GIS model field strength prediction
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Predicting Bursting Strength Behavior of Weft Knitted Fabrics Using Various Percentages of Cotton, Polyester, and Spandex Fibers
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作者 Kazi Md. Elias Mohammad Obaidur Rahman H. M. Zakir Hossain 《Journal of Textile Science and Technology》 2023年第4期273-290,共18页
The bursting strength is an essential quality parameter of knit fabric. The fabric structure, weight, types of fibers, and fiber blend proportion influence the bursting strength parameter. The tenacity of polyester fi... The bursting strength is an essential quality parameter of knit fabric. The fabric structure, weight, types of fibers, and fiber blend proportion influence the bursting strength parameter. The tenacity of polyester fiber is better than cotton and spandex. The study focused on predicting knit fabric bursting strength test value using different fibers (cotton, polyester, and spandex) with varying percentages of the blend ratio. This study used fifteen categories of blended fabrics. The Pearson Correlation and the hypothetical ANOVA regression analysis were conducted to do the statistical significance test. The experimental result reveals that the bursting strength test result increased with the increased percentage of polyester and suggested a suitable regression equation. The dominance of the polyester fiber was observed throughout the experiment, i.e., the higher the polyester blend proportion, the higher the bursting strength value. The inclusion of polyester in blends can reduce the cost of fabric. The developed prediction model or equation can help the fabric manufacturer make appropriate decisions regarding getting the expected bursting strength. The researcher hopes that the findings from this study will motivate new researchers, advanced researchers, and the textile manufacturing industry. 展开更多
关键词 Kilopascal prediction Bursting-strength Blended Fabric COTTON POLYESTER SPANDEX
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A Fuzzy Logic Approach to Predict Tensile Strength in TIG Mild Steel Welds
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作者 Ademola Adebiyi Oyinbade Kehinde Ademola Imoukhuede Abdulateef Olufolahan Akadiri 《World Journal of Engineering and Technology》 2023年第2期199-207,共6页
Welding defects influence the desired properties of welded joints giving fabrication experts a common problem of not being able to produce weld structures with optimal strength and quality. In this study, the fuz... Welding defects influence the desired properties of welded joints giving fabrication experts a common problem of not being able to produce weld structures with optimal strength and quality. In this study, the fuzzy logic system was employed to predict welding tensile strength. 30 sets of welding experiments were conducted and tensile strength data was collected which were converted from crisp variables into fuzzy sets. The result showed that the fuzzy logic tool is a highly effective tool for predicting tensile strength present in TIG mild steel weld having a coefficient of determination value of 99%. 展开更多
关键词 Tensile strength predict Steel Fuzzy Logic Tungsten Inert Gas Welding
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基于Stacking算法与钻进参数的岩石单轴抗压强度预测
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作者 岳中文 龙思晨 +5 位作者 闫逸飞 张梦佳 胡昊 薛克军 马文彪 李杨 《采矿与安全工程学报》 北大核心 2026年第1期198-207,共10页
针对传统岩石强度参数测试方法周期长、成本高的问题,本文提出一种基于Stacking集成算法的新型岩石单轴抗压强度预测方法。通过自主研发的岩石数字钻探测试系统,对不同强度材料的组合试件开展数字钻探试验;选择4种不同的机器学习算法(... 针对传统岩石强度参数测试方法周期长、成本高的问题,本文提出一种基于Stacking集成算法的新型岩石单轴抗压强度预测方法。通过自主研发的岩石数字钻探测试系统,对不同强度材料的组合试件开展数字钻探试验;选择4种不同的机器学习算法(包括支持向量机、随机森林、LightGBM和BP-神经网络),利用钻进数据训练相应的算法模型,探究钻进速度、扭矩和推进力与岩石单轴抗压强度之间的关系;采用双层Stacking框架融合4种抗压强度预测模型,构建集成算法模型,以解决单一算法模型预测精度不足、泛化能力差的问题。研究结果表明,Stacking算法模型在不同转速下对岩石单轴抗压强度的预测性能优异,300 r/min转速与400 r/min转速下对不同试件的单轴抗压强度预测结果决定系数R2基本高于0.9,优于其他4种基学习器,且平均绝对误差占实际强度值的比例小于5%。现场应用表明,Stacking算法模型能有效预测巷道岩层的岩石单轴抗压强度,可为岩体随钻探测研究提供新的思路和方法。 展开更多
关键词 钻进参数 Stacking算法 强度预测 集成学习 模型融合
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石灰石-粉煤灰-水泥胶凝体系的水化动力学模型及强度预测
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作者 吴浪 田玉凤 +2 位作者 郭毅 何美美 雷斌 《功能材料》 北大核心 2026年第2期10-18,共9页
石灰石-粉煤灰-水泥(LF^(3))作为一种新型辅助胶凝材料,具备良好的环境适应性和力学性能。然而,当前对其水化机制与强度发展规律的理论研究仍不充分。为此,综合考虑了石灰石、粉煤灰掺料的水化反应和火山灰反应过程,建立了LF^(3)胶凝体... 石灰石-粉煤灰-水泥(LF^(3))作为一种新型辅助胶凝材料,具备良好的环境适应性和力学性能。然而,当前对其水化机制与强度发展规律的理论研究仍不充分。为此,综合考虑了石灰石、粉煤灰掺料的水化反应和火山灰反应过程,建立了LF^(3)胶凝体系的水化动力学模型。模型基于氢氧化钙和铝酸盐反应机制,将水化伴生物(水、氢氧化钙)作为动态输入变量,模拟三元体系水化过程演化。进一步结合Powers强度理论,建立了水化程度驱动下的强度预测模型,并通过文献数据进行参数拟合与准确性验证。结果显示,模型预测强度与实测值相关性良好(R^(2)=0.99,RMSE=1.48 MPa),表明模型具备较强的适用性与泛化能力。研究表明,石灰石有助于提升早期强度,粉煤灰通过火山灰反应增强后期性能,LF^(3)体系整体优于二元复合胶凝材料及普通硅酸盐水泥。不同龄期下最优配比呈现由高石灰石-低粉煤灰向高粉煤灰-低石灰石转变的趋势。为LF^(3)胶凝体系的水化机制揭示与配比优化提供了理论支持,为低碳高性能混凝土设计提供预测工具。 展开更多
关键词 石灰石-粉煤灰-水泥(LF^(3)) 水化动力学 胶凝体系 强度预测
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Prediction Model of Compressive Strength of Fly Ash-Slag Concrete Based on Multiple Adaptive Regression Splines
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作者 Jianjun Dong Hongyang Xie +1 位作者 Yiwen Dai Yong Deng 《Open Journal of Applied Sciences》 2022年第3期284-300,共17页
Accurate prediction of compressive strength of concrete is one of the key issues in the concrete industry. In this paper, a prediction method of fly ash-slag concrete compressive strength based on multiple adaptive re... Accurate prediction of compressive strength of concrete is one of the key issues in the concrete industry. In this paper, a prediction method of fly ash-slag concrete compressive strength based on multiple adaptive regression splines (MARS) is proposed, and the model analysis process is determined by analyzing the principle of this algorithm. Based on the Concrete Compressive Strength dataset of UCI, the MARS model for compressive strength prediction was constructed with cement content, blast furnace slag powder content, fly ash content, water content, reducing agent content, coarse aggregate content, fine aggregate content and age as independent variables. The prediction results of artificial neural network (BP), random forest (RF), support vector machine (SVM), extreme learning machine (ELM), and multiple nonlinear regression (MnLR) were compared and analyzed, and the prediction accuracy and model stability of MARS and RF models had obvious advantages, and the comprehensive performance of MARS model was slightly better than that of RF model. Finally, the explicit expression of the MARS model for compressive strength is given, which provides an effective method to achieve the prediction of compressive strength of fly ash-slag concrete. 展开更多
关键词 Fly Ash-Slag Concrete Compressive strength Multiple Adaptive Regression Splines prediction Model
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基于改进随机森林算法的混凝土抗冻性预测
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作者 刘明 杨千葶 王志强 《沈阳建筑大学学报(自然科学版)》 北大核心 2026年第2期264-271,共8页
为探究混凝土在碳化、冻融循环及硫酸盐侵蚀作用下的抗冻性作用机理,建立适用于混凝土相对动弹性模量的预测模型,提出改进的随机森林(Improved Random Forest,IRF)算法。以水胶比、粉煤灰掺量、聚丙烯纤维掺量、Na_(2)SO_(4)溶液质量分... 为探究混凝土在碳化、冻融循环及硫酸盐侵蚀作用下的抗冻性作用机理,建立适用于混凝土相对动弹性模量的预测模型,提出改进的随机森林(Improved Random Forest,IRF)算法。以水胶比、粉煤灰掺量、聚丙烯纤维掺量、Na_(2)SO_(4)溶液质量分数和抗压强度为输入变量,混凝土相对动弹性模量为输出变量,分别采用BP、SVR、RF及IRF算法建立预测模型,并基于决定系数R^(2)、均方根误差RMSE及平均绝对误差MAE对各模型的预测性能进行对比,结果表明,IRF算法在混凝土相对动弹性模量预测中表现最优,其对应的R^(2)、RMSE及MAE分别为0.965 6、0.026 2及0.022 8。研究发现,抗压强度与混凝土相对动弹性模量呈正相关关系,而水胶比、粉煤灰掺量、聚丙烯纤维掺量及Na_(2)SO_(4)溶液质量分数均与相对动弹性模量呈负相关;当水胶比为0.45、粉煤灰掺量为30%且聚丙烯纤维掺量为1%时,混凝土配合比达到最优。此外,IRF模型通过合理的参数调优,在叶子节点选择上实现了最佳平衡,有效提升了模型的预测精度与泛化能力。 展开更多
关键词 混凝土 相对动弹性模量 随机森林算法 预测模型 抗压强度
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地聚物改良预崩解红砂岩筋土界面的摩擦特性
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作者 邱祥 范思齐 +4 位作者 蔡杰华 韦辰睿 彭龙辉 刘拥华 黄宇 《中南大学学报(自然科学版)》 北大核心 2026年第1期314-327,共14页
针对预崩解红砂岩加筋挡土墙因筋土界面摩擦强度不足导致的失稳问题,开展了地聚物改良预崩解红砂岩土工格栅拉拔试验,分析了在不同地聚物掺量、压实度、含水率、法向应力条件下,筋土界面拉拔摩擦强度、摩擦强度指标、似摩擦因数的变化... 针对预崩解红砂岩加筋挡土墙因筋土界面摩擦强度不足导致的失稳问题,开展了地聚物改良预崩解红砂岩土工格栅拉拔试验,分析了在不同地聚物掺量、压实度、含水率、法向应力条件下,筋土界面拉拔摩擦强度、摩擦强度指标、似摩擦因数的变化规律。研究结果表明:不同条件下拉拔力-位移曲线均呈现“缓慢增长、快速增长、渐趋稳定”三阶段演化特征,低应力下曲线呈现应变软化特征,高应力下则呈现应变硬化特征;筋土界面拉拔摩擦强度、摩擦强度及似摩擦因数与地聚物掺量、压实度均呈正相关,在含水率为11.2%时均达到峰值;地聚物对界面摩擦强度的提升作用主要体现在界面似黏聚力的增强;地聚物水化产物将土体颗粒胶结形成整体结构,增强了土体对土工格栅的嵌固与摩擦作用;据建立的筋土界面拉拔摩擦强度预估模型所得拉拔摩擦强度预测误差均在±10%内。研究结果可为加筋挡土墙工程设计提供参考。 展开更多
关键词 地聚物 预崩解红砂岩 土工格栅 拉拔试验 界面强度参数 预估模型
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第16届全运会田径投掷项目各主要省市竞技实力前瞻
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作者 曹司雨 李婷 《四川体育科学》 2026年第1期74-80,136,共8页
为揭示全运会投掷项目竞技格局演变规律,以第13—15届全运会投掷项目竞赛数据为研究对象,采用静态与动态分析、区域对比、模型构建与预测等方法,系统探究省市竞技实力演变、区域差异及整体发展趋势,并构建“奖牌指标+成绩指标+潜力指标... 为揭示全运会投掷项目竞技格局演变规律,以第13—15届全运会投掷项目竞赛数据为研究对象,采用静态与动态分析、区域对比、模型构建与预测等方法,系统探究省市竞技实力演变、区域差异及整体发展趋势,并构建“奖牌指标+成绩指标+潜力指标”三维评价体系,基于灰色预测模型对第16届全运会进行展望。研究表明:近三届投掷项目省市格局呈现“传统强省稳中有调、新兴省市精准突破”特征,江苏、山东、河北稳居第一梯队,河南、湖北等通过专项深耕跻身第二梯队;区域竞技实力呈“东强西弱、北强南弱”格局,华东区域为核心竞争力区,区域差距持续扩大且两极分化显著;项目整体竞技水平稳步上升,男子铁饼、女子铅球等项目进步突出,训练科学化与政策支持为核心驱动力。构建的评价体系契合实际赛事格局,预测第16届全运会将延续“强省垄断、专项深耕”特征,江苏有望蝉联领跑,新兴省市将进一步冲击奖牌格局。 展开更多
关键词 全运会 投掷项目 竞技实力 评价体系 灰色预测
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