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Stability Analysis of Inverse Lax-wendroff Procedure for a High order Compact Finite Difference Schemes

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Communications on Applied Mathematics and Computation 2024年第1期6卷 142-189页

作者： tingting Li Jianfang Lu Pengde wang School of Mathematics and Statistics Henan UniversityKaifeng475004HenanChina School of Mathematics South China University of TechnologyGuangzhou510641GuangdongChina College of Mathematics and Information Science Henan University of Economics and LawZhengzhou450046HenanChina

This paper considers the finite difference(FD)approximations of diffusion operators and the boundary treatments for different boundary *** proposed schemes have the compact form and could achieve arbitrary even order of *** main idea is to make use of the lower order compact schemes recursively,so as to obtain the high order compact schemes ***,the schemes can be implemented efficiently by solving a series of tridiagonal systems recursively or the fast Fourier transform(FFT).with mathematical induction,the eigenvalues of the proposed differencing operators are shown to be bounded away from zero,which indicates the positive definiteness of the *** obtain numerical boundary conditions for the high order schemes,the simplified inverse Lax-wendroff(SILw)procedure is adopted and the stability analysis is performed by the Godunov-Ryabenkii method and the eigenvalue spectrum visualization *** numerical experiments are provided to demonstrate the effectiveness and robustness of our algorithms.

关键词： Compact scheme Diffusion operators Inverse Lax-wendroff(ILw) Fourier analysis Eigenvalue analysis

Deterministic and probabilistic analysis of great-depth braced excavations:A 32 m excavation case study in Paris

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1505-1521页

作者： tingting Zhang Julien Baroth Daniel Dias Khadija Nejjar Université Grenoble Alpes CNRSGrenoble INP3SRGrenoble38000France Antea Group Antony92160France School of Automotive and Transportation Engineering Hefei University of TechnologyHefei23009China Terrasol 42-52 Quai de la RapéeParis75012France

The Fort d’Issy-Vanves-Clamart(FIVC)braced excavation in France is analyzed to provide insights into the geotechnical serviceability assessment of excavations at great depth within deterministic and probabilistic *** FIVC excavation is excavated at 32 m below the ground surface in Parisian sedimentary basin and a plane-strain finite element analysis is implemented to examine the wall deflections and ground surface settlements.A stochastic finite element method based on the polynomial chaos Kriging metamodel(MSFEM)is then proposed for the probabilistic *** with field measurements and former studies are carried *** academic cases are then conducted to investigate the great-depth excavation stability regarding the maximum horizontal wall deflection and maximum ground surface *** results indicate that the proposed MSFEM is effective for probabilistic analyses and can provide useful insights for the excavation design and construction.A sensitivity analysis for seven considered random parameters is then *** soil friction angle at the excavation bottom layer is the most significant one for *** soil-wall interaction effects on the excavation stability are also given.

关键词： Braced deep excavation Soil-wall interaction Stochastic finite element method Horizontal wall deflection Settlement Failure probability

Probabilistic analysis of tunnel face seismic stability in layered rock masses using Polynomial Chaos Kriging metamodel

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2678-2693页

作者： Jianhong Man tingting Zhang Hongwei Huang Daniel Dias Department of Geotechnical Engineering Key Laboratory of Geotechnical and Underground Engineering of Ministry of EducationCollege of Civil EngineeringTongji UniversityShanghai200092China Grenoble Alpes 3SR LabCNRS UMR 5521Grenoble38000France

Face stability is an essential issue in tunnel design and *** rock masses are typical and ubiquitous;uncertainties in rock properties always *** view of this,a comprehensive method,which combines the Upper bound Limit analysis of Tunnel face stability,the Polynomial Chaos Kriging,the Monte-Carlo Simulation and Analysis of Covariance method(ULT-PCK-MA),is proposed to investigate the seismic stability of tunnel faces.A two-dimensional analytical model of ULT is developed to evaluate the virtual support force based on the upper bound limit *** efficient probabilistic analysis method PCK-MA based on the adaptive Polynomial Chaos Kriging metamodel is then implemented to investigate the parameter uncertainty *** input parameters,including geological strength indices,uniaxial compressive strengths and constants for three rock formations,and the horizontal seismic coefficients,are treated as random *** effects of these parameter uncertainties on the failure probability and sensitivity indices are *** addition,the effects of weak layer position,the middle layer thickness and quality,the tunnel diameter,the parameters correlation,and the seismic loadings are investigated,*** results show that the layer distributions significantly influence the tunnel face probabilistic stability,particularly when the weak rock is present in the bottom *** efficiency of the proposed ULT-PCK-MA is validated,which is expected to facilitate the engineering design and construction.

关键词： Tunnel face stability Layered rock masses Polynomial Chaos Kriging(PCK) Sensitivity index Seismic loadings

A Quantitative Seismic Topographic Effect Prediction Method Based upon BP Neural Network Algorithm and FEM Simulation

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Journal of Earth Science 2024年第4期35卷 1355-1366页

作者： Qifeng Jiang Mianshui Rong wei wei tingting Chen Shandong Seismic Hazard Prevention Center Shandong Earthquake AgencyJinan250014China Shandong Institute of Earthquake Engineering Jinan250021China Key Laboratory of Urban Security and Disaster Engineering of China Ministry of Education Beijing University of TechnologyBeijing100124China Publicity and Education Center Shandong Earthquake AgencyJinan250014China Shandong Earthquake Station Shandong Earthquake AgencyJinan250014China

Topography can strongly affect ground motion,and studies of the quantification of hill surfaces’topographic effect are relatively *** this paper,a new quantitative seismic topographic effect prediction method based upon the BP neural network algorithm and three-dimensional finite element method(FEM)was *** FEM simulation results were compared with seismic records and the results show that the PGA and response spectra have a tendency to increase with increasing elevation,but the correlation between PGA amplification factors and slope is not obvious for low *** BP neural network models were established for the prediction of amplification factors of PGA and response *** kinds of input variables’combinations which are convenient to achieve are proposed in this paper for the prediction of amplification factors of PGA and response spectra,*** absolute values of prediction errors can be mostly within 0.1 for PGA amplification factors,and they can be mostly within 0.2 for response spectra’s amplification *** input variables’combination can achieve better prediction performance while the other one has better expandability of the predictive ***,the BP models only employ one hidden layer with about a hundred nodes,which makes it efficient for training.

关键词： seismic topographic effect finite element method BP neural network algorithm earthquake disaster prevention

Facile synthesis of high-brightness green-emitting carbon dots with narrow bandwidth towards backlight display

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Chinese Chemical Letters 2024年第5期35卷 277-282页

作者： Rui Cheng tingting Zhang Xin Huang Jian Yu State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 210009China

High-performance carbon dots(CDs)allowing the application in high-end display devices are highly desirable and usually limited by the absence of simple and easy synthesis *** this work,we exploited an easy-to-implement strategy for the one-step synthesis of green-emitting CDs(G-CDs)with superb optical *** G-CDs were synthesized using m-phenylenediamine(m-PD)as a single precursor,and the reaction reacted at 180℃for 12 h The resultant G-CDs exhibit high-purity and excitationindependent green fluorescence with the photoluminescence(PL)peak located at 516 nm,full width at half maximum(FwHM)of 46 nm,and PL quantum yield(QY)of∼80%under the 470nm excitation *** G-CDs and corresponding composite film prepared with polyvinyl butyral(G-CDs@PVB)exhibit good PL stability after undergoing long-time storage for one year and 360 h exposure under 460nm blue *** G-CDs@PVB film was used as color-conversion materials in green-emitting light-emitting diode(LED)application,exhibiting a Commission internationale de l’Eclairage(CIE)chromaticity coordinate of(0.21,0.44).The film was also used in CD-based liquid crystal display(CD-LCD)application,achieving a color gamut value of 85%.This work will offer a working basis for the synthesis of high-performance CDs as well as their application in displays.

关键词： Carbon dots One-step synthesis Narrow bandwidth High quantum yield Display

Enhancing source domain availability through data and feature transfer learning for building power load forecasting

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Building Simulation 2024年第4期17卷 625-638页

作者： Fanyue Qian Yingjun Ruan Huiming Lu Hua Meng tingting Xu College of Mechanical and Energy Engineering Tongji UniversityShanghai200092China United Automotive Electronic Systems Co. LtdShanghai201206China

During the initial phases of operation following the construction or renovation of existing buildings,the availability of historical power usage data is limited,which leads to lower accuracy in load forecasting and hinders normal ***,by transferring load data from similar buildings,it is possible to enhance forecasting ***,indiscriminately expanding all source domain data to the target domain is highly likely to result in negative transfer *** study explores the feasibility of utilizing similar buildings(source domains)in transfer learning by implementing and comparing two distinct forms of multi-source transfer ***,this study focuses on the Higashita area in Kitakyushu City,Japan,as the research *** buildings that exhibit the highest similarity to the target buildings within this area were selected for ***,the two-stage TrAdaBoost.R^(2) algorithm is used for multi-source transfer learning,and its transfer effect is ***,the application effects of instance-based(IBMTL)and feature-based(FBMTL)multi-source transfer learning are compared,which explained the effect of the source domain data on the forecasting accuracy in different transfer *** results show that combining the two-stage TrAdaBoost.R^(2) algorithm with multi-source data can reduce the CV-RMSE by 7.23%compared to a single-source domain,and the accuracy improvement is *** the same time,multi-source transfer learning,which is based on instance,can better supplement the integrity of the target domain data and has a higher forecasting ***,IBMTL tends to retain effective data associations and FBMTL shows higher forecasting *** findings of this study,which include the verification of real-life algorithm application and source domain availability,can serve as a theoretical reference for implementing transfer learning in load forecasting.

关键词： building power load multi-source transfer learning two-stage TrAdaBoost.R2 source domain availability

Characterization of size-resolved effective density of atmospheric particles in an urban atmosphere in Southern China

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Journal of Environmental Sciences 2024年第7期141卷 194-204页

作者： tingting Xie Liming Cao Jinyi Zheng Peng Xuan Xiaofeng Huang Laboratory of Atmospheric Observation Supersite School of Environment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China

Effective density(ρ_(eff))is one of the most important physical properties of atmospheric particles,providing important references in exploring the emissions and aging processes of fresh *** this study,a combined system of differential mobility analyzer,centrifugal particle mass analyzer,and condensation particle counter was used to periodically measure theρ_(eff)of atmospheric particles in Shenzhen from Oct.2021 to *** showed that theρ_(eff)of particles with various size presented a bimodal distribution,which could be divided into main density(ρ_(m),main peak,corresponding to relatively dense particles after aging)and sub density(ρ_(s),sub peak,corresponding to fresh particles).The occurrence frequencies ofρ_(s)of particles with diameters of 50 and 80 nm were less than 20%,but were as high as about 40%of that with diameters from 120 to 350 ***ρ_(m)showed increasing trend with the size of particles,whileρ_(s)decreased as the increasing of the size of ***ρ_(eff)on pollution day varied significantly with chemical *** increasing of the proportion of sulfate could promote the increasing ofρ_(eff),while black carbon and organic matter caused opposite effects,which may be related to various factors,including the difference of the material density and morphology of various chemical ***ρ_(eff)of 50,80 and 120 nm particles decreased considerably during the new particle formation event,indicating that organic condensation was an important contributor to new particle growth.

关键词： DMA-CPMA-CPC Effective density Main/sub density Size distribution

The pathogenesis of Parkinson’s disease and crosstalk with other diseases

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BIOCELL 2024年第8期48卷 1155-1179页

作者： tingting LIU DINGYOU GUO JIANSHE wEI Institute for Brain Sciences Research School of Life SciencesHenan UniversityKaifeng475004China

In China,Parkinson’s disease(PD)is the second most prevalent central nervous system(CNS)degenerative illness affecting middle-aged and older *** disorders including resting tremor,bradykinesia,myotonia,postural instability,and gait instability are the predominant clinical *** two main types of PD are sporadic and familial,with sporadic PD being the more prevalent of the *** environment,genetics,mitochondrial dysfunction,oxidative stress,inflammation,protein aggregation and misfolding,loss of trophic factors,cell death,and gut microbiota may all have a role in the etiology of *** is inversely connected with other cancers and positively correlated with COVID-19,diabetes mellitus(DM),melanoma,and ischemic heart disease(IHD)*** disease progression,managing motor and non-motor symptoms,and avoiding and controlling dysfunction in the middle and later phases of the disease are the key areas of research and development for its ***,the development and progression of PD can be slowed down by using conventional pharmacology,natural items,and innovative *** article reviews the pathogenesis of PD,its correlations with other non-genetic diseases,and the research progress of drugs and technologies for alleviating PD.

关键词： Parkinson’s disease Mitochondrial dysfunction Oxidative stress Inflammation Cancer Therapies

Stroke Risk Assessment Decision-Making Using a Machine Learning Model:Logistic-AdaBoost

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 699-724页

作者： Congjun Rao Mengxi Li tingting Huang Feiyu Li School of Science Wuhan University of TechnologyWuhan430070China wuhan University of Technology Hospital Wuhan University of TechnologyWuhan430070China

Stroke is a chronic cerebrovascular disease that carries a high *** risk assessment is of great significance in preventing,reversing and reducing the spread and the health hazards caused by *** to objectively predict and identify strokes,this paper proposes a new stroke risk assessment decision-making model named Logistic-AdaBoost(Logistic-AB)based on machine ***,the categorical boosting(CatBoost)method is used to perform feature selection for all features of stroke,and 8 main features are selected to form a new index evaluation system to predict the risk of ***,the borderline synthetic minority oversampling technique(SMOTE)algorithm is applied to transform the unbalanced stroke dataset into a balanced ***,the stroke risk assessment decision-makingmodel Logistic-AB is constructed,and the overall prediction performance of this new model is evaluated by comparing it with ten other similar *** comparison results show that the new model proposed in this paper performs better than the two single algorithms(logistic regression and AdaBoost)on the four indicators of recall,precision,F1 score,and accuracy,and the overall performance of the proposed model is better than that of common machine learning *** Logistic-AB model presented in this paper can more accurately predict patients’stroke risk.

关键词： Stroke risk assessment decision-making CatBoost feature selection borderline SMOTE Logistic-AB