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Application of machine learning technique for predicting and evaluating chloride ingress in concrete

Frontiers of Structural and Civil engineering 2022年第9期16卷 1153-1169页

作者： Van Quan TRAN Van Loi GIAP Dinh Phien VU Riya Catherine GEORGE Lanh Si HO Department of Civil Engineering University of Transport TechnologyHanoi 100000Vietnam Civil and Environmental Engineering Program Graduate School of Advanced Science and EngineeringHiroshima UniversityHiroshima 739-8527Japan

The degradation of concrete structure in the marine environment is often related to chloride-induced corrosion of reinforcement ***,the chloride concentration in concrete is a vital parameter for estimating the corrosion level of reinforcement *** research aims at predicting the chloride content in concrete using three hybrid models of gradient boosting(GB),artificial neural network(ANN),and random forest(RF)in combination with particle swarm optimization(PSO).The input variables for modeling include exposure condition,water/binder ratio(W/B),cement content,silica fume,time exposure,and depth of *** results indicate that three models performed well with high accuracy of prediction(R2⩾0.90).Among three hybrid models,the model using GB_PSO achieved the highest prediction accuracy(R2=0.9551,RMSE=0.0327,and MAE=0.0181).Based on the results of sensitivity analysis using SHapley Additive exPlanation(SHAP)and partial dependence plots 1D(PDP-1D),it was found that the exposure condition and depth of measurement were the two most vital variables affecting the prediction of chloride *** the number of different exposure conditions is larger than two,the exposure significantly impacted the chloride content of concrete because the chloride ion ingress is affected by both chemical and physical *** study provides an insight into the evaluation and prediction of the chloride content of concrete in the marine environment.

关键词： gradient boosting random forest chloride content concrete sensitivity analysis

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Optimization of machine learning models for predicting the compressive strength of fiber-reinforced self-compacting concrete

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Frontiers of Structural and Civil engineering 2023年第2期17卷 284-305页

作者： Hai-Van Thi MAI May Huu NGUYEN Son Hoang TRINH Hai-Bang LY Civil Engineering Department University of Transport TechnologyHanoi 100000Vietnam Civil and Environmental Engineering Program Graduate School of Advanced Science and EngineeringHiroshima UniversityHiroshima 739-8527Japan

Fiber-reinforced self-compacting concrete(FRSCC)is a typical construction material,and its compressive strength(CS)is a critical mechanical property that must be adequately *** the machine learning(ML)approach to estimating the CS of FRSCC,the current research gaps include the limitations of samples in databases,the applicability constraints of models owing to limited mixture components,and the possibility of applying recently proposed *** study developed different ML models for predicting the CS of FRSCC to address these *** neural network,random forest,and categorical gradient boosting(CatBoost)models were optimized to derive the best predictive model with the aid of a 10-fold cross-validation technique.A database of 381 samples was created,representing the most significant FRSCC dataset compared with previous studies,and it was used for model *** findings indicated that CatBoost outperformed the other two models with excellent predictive abilities(root mean square error of 2.639 MPa,mean absolute error of 1.669 MPa,and coefficient of determination of 0.986 for the test dataset).Finally,a sensitivity analysis using a partial dependence plot was conducted to obtain a thorough understanding of the effect of each input variable on the predicted CS of *** results showed that the cement content,testing age,and superplasticizer content are the most critical factors affecting the CS.

关键词： compressive strength self-compacting concrete artificial neural network decision tree CatBoost

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ELEMENTAL CARBON AEROSOLS IN THE URBAN, RURAL, AND REMOTE-MARINE TROPOSPHERE AND IN THE STRATOSPHERE - INFERENCES FROM LIGHT-ABSORPTION DATA AND CONSEQUENCES REGARDING RADIATIVE-TRANSFER

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science OF THE TOTAL ENVIRONMENT 1984年第JUN期36卷 97-102页

作者： CLARKE, AD WEISS, RE CHARLSON, RJ Environmental Engineering and Science Program Dept. of Civil Engineering University of Washington Seattle WA 98195 U.S.A.

Light absorption by carbon particles has been clearly demonstrated to be important to urban and regional scale radiative processes, with questions remaining about the global scale. Measurements of the light absorption coefficient of size-classified samples of aerosol particles from a wide variety of locations reveal a nearly ubiquitous presence of optically effective carbonaceous particles concentrated in the submicron sizes. Light absorption coefficients at 0.5 μm wavelength for urban areas range from 10 −5 m −1 or less to well over 10 −3 m −1 . Remote marine and stratospheric locations exhibit values as low as a few times 10 −8 m −1 (referenced to sea level) with rural areas in between. Both chemical analysis (in urban/rural cases) and mass absorptivities (in remote cases) indicate that the light absorption is largely due to an elemental carbon component. Since this material probably is produced exclusively by combustion of carbon-based materials and since this occurs primarily on land, the elemental carbon in remote locations may be a residue which has undergone long-distance transport. This hypothesis can be used as the basis for a simple flow diagram which portrays the urban/industrial regions as the source, dispersion carrying carbon aerosol through rural to remote areas with removal occurring continuously or periodically over the lifetime. Via this model the data allow a crude estimation of the regional and hemispheric influence of sources. Collected data will be summarized with ancillary estimates heating rate, demonstrating the range of expected radiative effects.

关键词： Aerosol Carbon, elemental Light absorption data

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A hybrid machine learning model to estimate self-compacting concrete compressive strength

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Frontiers of Structural and Civil engineering 2022年第8期16卷 990-1002页

作者： Hai-Bang LY Thuy-Anh NGUYEN Binh Thai PHAM May Huu NGUYEN Civil Engineering Department University of Transport TechnologyHanoi 100000Vietnam Civil and Environmental Engineering Program Graduate School of Advanced Science and EngineeringHiroshima UniversityHiroshima 739-8527Japan

This study examined the feasibility of using the grey wolf optimizer(GWO)and artificial neural network(ANN)to predict the compressive strength(CS)of self-compacting concrete(SCC).The ANN-GWO model was created using 115 samples from different sources,taking into account nine key SCC *** validation of the proposed model was evaluated via six indices,including correlation coefficient(R),mean squared error,mean absolute error(MAE),IA,Slope,and mean absolute percentage *** addition,the importance of the parameters affecting the CS of SCC was investigated utilizing partial dependence *** results proved that the proposed ANN-GWO algorithm is a reliable predictor for SCC’s *** that,an examination of the parameters impacting the CS of SCC was provided.

关键词： artificial neural network grey wolf optimize algorithm compressive strength self-compacting concrete

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Real-Time Quantum Dynamics of Long-Range Electronic Excitation Transfer in Plasmonic Nanoantennas (vol 13, pg 3442, 2017)

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JOURNAL OF CHEMICAL THEORY AND COMPUTATION 2017年第12期13卷 6433-6433页

作者： Ilawe, Niranjan V. Oviedo, M. Belen Wong, Bryan M. Department of Chemical & Environmental Engineering and Materials Science & Engineering Program University of California Riverside Riverside California 92521 United States

Using large-scale, real-time, quantum dynamics calculations, we present a detailed analysis of electronic excitation transfer (EET) mechanisms in a multiparticle plasmonic nanoantenna system. Specifically, we utilize real-time, time-dependent, density functional tight binding (RT-TDDFTB) to provide a quantum-mechanical description (at an electronic/atomistic level of detail) for characterizing and analyzing these systems, without recourse to classical approximations. We also demonstrate highly long-range electronic couplings in these complex systems and find that the range of these couplings is more than twice the conventional cutoff limit considered by Förster resonance energy transfer (FRET)-based approaches. Furthermore, we attribute these unusually long-ranged electronic couplings to the coherent oscillations of conduction electrons in plasmonic nanoparticles. This long-range nature of plasmonic interactions has important ramifications for EET; in particular, we show that the commonly used “nearest-neighbor” FRET model is inadequate for accurately characterizing EET even in simple plasmonic antenna systems. These findings provide a real-time, quantum-mechanical perspective for understanding EET mechanisms and provide guidance in enhancing plasmonic properties in artificial light-harvesting systems.

关键词： Nanodevices Plasmonics Coupling reactions Polarity Fluorescence resonance energy transfer

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PACIFIC MARINE AEROSOL AND EVIDENCE FOR A FINE PARTICLE SULFURIC ACID COMPONENT.

PACIFIC MARINE AEROSOL AND EVIDENCE FOR A FINE PARTICLE SULF...

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Aerosols: science, Technology, and Industrial Applications of Airborne Particles, Proceedings of the First International Aerosol Conference.

作者： Clarke, Anthony D. Covert, David S. Ahlquist, Norman C. Univ of Washington Environmental Engineering & Science Program Seattle WA USA Univ of Washington Environmental Engineering & Science Program Seattle WA USA

ISBN: (纸本)0444009477

The majority of data were collected in the central Pacific ocean between 30 degree N and 30 degree S and 130 degree W and 155 degree W. During the KOROLEV cruise, a general symmetry in several aerosol optical and physical parameters was observed for both Northern and Southern hemispheres centered on the Intertropical Convergence Zone, while a minima in aerosol mass concentration was observed for this region. An exception was observed for the fine particle size distribution as measured by an active scattering aerosol spectrometer probe.

关键词： AEROSOLS

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EXPLORATORY DATA ANALYSIS OF RAINWATER COMPOSITION.

EXPLORATORY DATA ANALYSIS OF RAINWATER COMPOSITION.

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188th National Meeting - American Chemical Society, Division of environmental Chemistry, Volume 24 Number 2.

作者： Vong, Richard J. Frank, Ildiko E. Charlson, Robert J. Kowalski, Bruce R. Univ of Washington Environmental Engineering & Science Program Seattle WA USA Univ of Washington Environmental Engineering & Science Program Seattle WA USA

In a search for the chemical and meteorological factors controlling rainwater composition the authors have demonstrated the performance of these techniques in the analysis of data consisting of rainwater samples collected weekly at four sites in Western Washington State in 1982-83. The approach we have undertaken involves the identification of the underlying factors governing precipitation composition at individual sites supplemented by identification of the factors which link the local composition at different sites within a region. Major steps in this type of analysis include initial data scaling and transformation, outlier detection, determination of the underlying factors, and evaluation of the effect that experimental procedures may have on the variance of the results. Most of the calculations were performed with the ARTHUR software package.

关键词： RAIN AND RAINFALL

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SIMPLIFIED KINETIC ANALYSIS OF THE ANAEROBIC FLUIDIZED BED REACTOR.

SIMPLIFIED KINETIC ANALYSIS OF THE ANAEROBIC FLUIDIZED BED R...

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Proceedings of the 39th Industrial Waste Conference.

作者： Mueller, James A. Subburamu, K. Donovan Jr., Eugene J. Manhattan Coll Environmental Engineering & Science Program Bronx NY USA Manhattan Coll Environmental Engineering & Science Program Bronx NY USA

ISBN: (纸本)0250406403

A pilot study on anaerobic treatment of the foul condensate from an ammonia based spent sulfite liquor evaporator has recently been conducted at the Proctor & Gamble Paper Products Plant in Mehoopany, Pennsylvania. The study involved construction of pilot plants representative of three technologies commercially available with a seven month (January to July 1983) pilot plant program to compare their performance. The three pilot systems studied were the anaerobic filter, the anaerobic upflow sludge blanket (contact) bed, and the anaerobic fluidized bed. This paper presents the development and results of the kinetic analysis on the anaerobic fluidized bed reactor along with a brief summary of the removals obtained on the three systems studied.

关键词： PULP MANUFACTURE

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MINIMIZING CONTAMINATION HAZARDS TO WATERBIRDS USING AGRICULTURAL DRAINAGE EVAPORATION PONDS

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environmental MANAGEMENT 1991年第6期15卷 785-795页

作者： BRADFORD, DF SMITH, LA DREZNER, DS SHOEMAKER, JD 1. Environmental Science and Engineering Program School of Public Health University of California 90024 Los Angeles California USA

In much of the San Joaquin Valley, California, USA. inadequate drainage of applied irrigation water and accumulating salts in the soil have necessitated the installation of subsurface tile drainage systems to preserve crop productivity. At present, these subsurface drainage waters are disposed of by means of evaporation ponds or discharges into the San Joaquin River. Unfortunately, most of these agricultural drainage waters contain high concentrations of salts and naturally occurring trace elements, such as selenium, and recent evidence indicates that substantial numbers of waterbirds are exposed to contamination by selenium in the evaporation ponds. In order to avoid, minimize, or mitigate the adverse impacts on wildlife using the ponds, alternative pond management methods must be identified and evaluated for implementation. A number of methods have the potential to be cost-effective in significantly reducing the contamination hazard to birds using agricultural evaporation ponds. Twenty general methods were evaluated in this study, and four methods are recommended for implementation: remove levee vegetation. remove windbreaks, deepen the ponds, and haze birds. A number of other methods are recommended for further consideration because they appear to have good prospects for reducing the contamination hazard: steepen interior levee slopes, apply herbicides and insecticides, place netting on pond shorelines, and provide freshwater habitat adjacent to evaporation ponds. It may be necessary to use a combination of methods to effectively control selenium contamination of aquatic birds because it is unlikely that a single affordable pond management method will be able to entirely eliminate the contamination hazard.

关键词： AGRICULTURAL PONDS BIRDS EVAPORATION PONDS SELENIUM SELENIUM CONTAMINATION SHOREBIRDS SUBSURFACE DRAINAGE WATERFOWL

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Machine learning-based analysis on factors influencing blood heavy metal concentrations in the Korean CHildren's environmental health Study (Ko-CHENS)

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science of the Total Environment 2025年 978卷

作者： Jung, Seowoo Shah, Surabhi Oh, Jongmin Bang, Yoorim Lee, Ji Hyen Kim, Hwan-Cheol Jeong, Kyoung Sook Park, Huibyeol Lee, Eun-Kyung Hong, Yun-Chul Ha, Eunhee Department of Statistics Ewha Womans University Seoul Korea Republic of Department of Environmental Medicine College of Medicine Ewha Womans University Seoul Korea Republic of Department of Human Systems Medicine College of Medicine Seoul National University Seoul Korea Republic of College of Medicine Ewha Womans University Seoul Korea Republic of Institute for Development and Human Security Ewha Womans University Seoul Korea Republic of Department of Pediatrics College of Medicine Ewha Womans University Seoul Korea Republic of Department of Occupational and Environmental Medicine College of Medicine Inha University Hospital Inha University Incheon Korea Republic of Department of Occupational and Environmental Medicine Wonju College of Medicine Wonju Severance Christian Hospital Yonsei University Wonju Korea Republic of Environmental Health Research Division National Institute of Environmental Research Incheon Korea Republic of Institute of Environmental Medicine Medical Research Center Seoul National University Korea Republic of Graduate Program in System Health Science and Engineering Ewha Womans University Ewha Medical Research Institute College of Medicine Seoul Korea Republic of

Heavy metal concentration in pregnant women affects neurocognitive and behavioral development of their infants and children. The majority of existing research focusing on pregnant women's heavy metal concentration has considered individual environmental factor. In this study, we aim to comprehensively consider lifestyle, food, and environmental factors to determine the most influential factor affecting heavy metal concentration in pregnant women. The Ko-CHENS (Korean CHildren health and environmental Study) is a nationwide prospective birth cohort study in South Korea enrolling pregnant women from 2015 to 2020. A total of 5458 eligible pregnant women were included in this study, and 897 variables were included in questionnaire comprising: maternal general information, indoor and living environment, dietary habits, health behavior, exposure to chemicals. Lead, cadmium and mercury concentration on blood were measured in early, late pregnancy and in cord blood at birth. Variables that might be related to heavy metal concentrations were included in machine learning models. Random forest and XGBoost machine learning models were conducted for predictions. Both models had similar but better performance than multiple linear regression. Kimchi (β = 1.55), seaweed (β = 0.40), fatty fish (β = 1.55), intakes respectively affected lead, cadmium, and mercury exposure through early, late pregnancy and cord blood. © 2025

关键词： Obstetrics

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