Reconstruction of 3D Micro Pore Structure of Coal and Simulation of Its Mechanical Properties by Guang-zhe Deng, Rui Zheng

“…The numerical simulation study of reconstructed pore model shows that (1) the porosity and the compressive strength have obvious nonlinear relation and satisfy the negative exponential relation; (2) the porosity significantly affects the stress distribution; with the increase of micro porosity, the stress distribution becomes nonuniform; (3) the compressive failures of different models are mainly shear failures, and the shape of fracture section is related to porosity; (4) the variation of seepage coefficient of the pore reconstruction model is consistent with the development of micro cracks. …”
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OPTIMIZATION OF MACHINING PARAMETERS BASED ON ADAPTIVE QUANTUM PARTICLE SWARM NETWORKS (MT) by HAN HuiHui, FU Hui

“…Particle swarm optimization（PSO） method and improved Elman network are combined to solve the nonlinear and multi-constraint problems of multi-objective NC cutting parameter optimization. …”
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Vibration Characteristic Analysis of a Coupling System for Compound Biaxial and Inter-Shaft Bearings by Kun Li, Hongchang Ding, Guohua Cao, Han Hou

“…Based on the Runge-Kutta iterative method and Hamilton’s principle, the nonlinear amplitude-frequency response of the system is calculated while taking into account the influence of the compound biaxial eccentricity, as well as the stiffness and radial clearance of the inter-shaft bearing. …”
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The Research on Improved Companding Transformation for Reducing PAPR in Underwater Acoustic OFDM Communication System by Jinqiu Wu, Gang Qiao, Xiaofei Qi

“…To solve the problem of the high peak-to-average power ratio (PAPR) in Orthogonal Frequency Division Multiplexing (OFDM) for the underwater acoustic communication system, the paper offers a method of reducing PAPR which combines the amplitude limiting and the improved nonlinear transformation. Traditional amplitude limiting technique can reduce PAPR in OFDM system effectively, at the cost of reducing the bit error rate (BER). …”
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Comparing the Velocity Spectrum Caused by the Presence of Circular Urban Subway Tunnels With Free-Field Conditions by Hamed Fakhriyeh, Reza Vahdani, Mohsen Gerami

“…The findings indicate that the velocity spectrum diagram’s envelope for the tunnel crown is a nonlinear function of the soil–tunnel system’s period.…”
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Identification of Accounting Fraud Based on Support Vector Machine and Logistic Regression Model by Rongyuan Qin

“…However, more and more studies show that fraud has typical nonlinear characteristics, and the multiobjective of fraud means also determines the limitations of using the linear model for identification. …”
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A posteriori Variational Multiscale Methods for the 1D convection-diffusion equations by Chacón Rebollo, Tomás, Domínguez-Delgado, Antonio, Gómez Marmol, Macarena

“…We present an extension of this technique to nonlinear convection-diffusion equations (a traffic model), providing an efficient method for the resolution of shocks from just the Galerkin solution at targeted times. …”
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Slope Deformation Prediction Based on IVDF-SVR Coupling Model by HOU Taiping, YANG Qiandong, LU Xuefeng, JIANG Lei, WU Anjie, HUANG Xiuyin

“…Given the shortcomings of improved variable-dimension fractal in the fitting and prediction of fractal dimensions,this paper proposes a fractal prediction model based on the coupling of the improved variable-dimension fractal (IVDF) theory and the support vector regression (SVR) machine theory,namely the IVDF-SVR coupling model.The model uses the SVR machine theory to fit and predict the fractal dimension sequence in the original improved variable-dimension fractal model.This paper takes the slope displacement monitoring data of Maoping Landslide as an example and selects the dimensioned segmented ln(r)-ln(S1) curve of the cumulative sum sequence as the fractal parameter curve of the prediction model.The IVDF model is utilized to calculate the segmented fractal dimension of each curve,and slope displacement is predicted.Then,the IVDF-SVR coupling model is used for another round of calculation and prediction.The prediction results show that the IVDF-SVR coupling model makes full use of the self-similarity in the fractal theory so that the prediction model has strong noise resistance.Moreover,by incorporating the self-learning ability in the SVR theory,it enables data fitting and prediction under small samples and nonlinear conditions.These advantages provide the proposed model with a favorable prediction length,high prediction accuracy,and ultimately a bright application prospect.…”
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Tension Strength Prediction of Transverse Branch Plate-to-Rectangular Joint with Concrete Filling by Zhihua Xiong, Yongjian Liu, Bin Liu, Lei Jiang

“…Tension strength equations were proposed for both CBPRH joints with and without PBR by nonlinear regression. The chord axial stress reduction factor was discussed and a modified equation originated from hollow joint was recommended for CBPRH joint. …”
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Spectral Representation-Based Multidimensional Nonstationary Ground Motion Model for Seismic Reliability Analysis of Frame Structures by Lawali Moussa Laminou, Xinghua Chen

“…In the numerical analysis, the nonlinear seismic responses and reliability of a 10-story reinforced concrete frame structure are carefully investigated in accordance with the Egyptian seismic code. …”
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Shield Tunneling Parameter Matching Model and UI Interface by Gongyu Hou, Zhedong Xu, Le Li, Xiaoge Quan, Yajie Yang

“…In order to improve the accuracy of shield tunneling parameter matching under the limited data, the matching model based on support vector machine (SVM) and exponential adjustment inertia weight immune particle swarm optimization (EAIW-IPSO) is proposed. The nonlinear relationship model between the tunneling parameters and the ground settlement is constructed by SVM and trained with the actual engineering sample data. …”
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Financial Futures Prediction Using Fuzzy Rough Set and Synthetic Minority Oversampling Technique by Shangkun Deng, Yingke Zhu, Ruijie Liu, Wanyu Xu

“…Then, the FRS- (fuzzy rough set-) based method, as an efficient tool for analyzing complex and nonlinear information with high noise and uncertainty of financial time series, is adopted for the price change multiclassification of the CSI300 futures. …”
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A Three-Dimensional Autonomous System with a Parabolic Equilibrium: Dynamical Analysis, Adaptive Synchronization via Relay Coupling, and Applications to Steganography and Chaos Enc... by Janarthanan Ramadoss, Romanic Kengne, Dianorré Tokoue Ngatcha, Victor Kamdoum Tamba, Karthikeyan Rajagopal, Marceline Motchongom Tingue

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Selection of Machine Learning Models for Oil Price Forecasting: Based on the Dual Attributes of Oil by Lei Yan, Yuting Zhu, Haiyan Wang

“…In addition, the LLE-RNN/LSTM models can most successfully capture the nonlinear characteristics of crude oil prices. When the moving window size is twenty, that is, when crude oil price data are lagging by almost a month, each model can minimize its error, and the LLE-RNN /LSTM models have the best robustness.…”
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Experimental Research on Internal Behaviors of Caved Rocks under the Uniaxial Confined Compression by Yu-jiang Zhang, Guo-rui Feng, Ting-ye Qi

“…A stratification phenomenon of breakage was discovered, which presents breakage concentration in the middle of the sample. The nonlinear movement and shear dislocation induced by shifts among caved rocks are the reason of the breakage stratification phenomenon. …”
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Rolling bearing fault diagnosis method based on gramian angular difference field and dynamic self-calibrated convolution module. by Chunli Liu, Jiarui Bai, Linlin Xue, Zhengkun Xue

“…First, the GADF method converts one-dimensional signals into GADF images to capture nonlinear relationships and periodic information in time-series data. …”
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Shear Behavior of RC Beams Strengthened by External Vertical Prestressing Rebar by Ying Li, Meizhong Wu, Weiqi Wang, Xingwei Xue

“…The objectives of this study are to simulate EVPR strengthening of concrete beams using a nonlinear three-dimensional finite element model and to explore its shear enhancement features under different EVPR stirrup ratios, vertical compressive stress degrees, and optimal arrangements of EVPRs. …”
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Coupling Ratio-Based Design and Seismic Performance of Modular Prefabricated Hybrid Coupled Walls by Yun Shi, Yumin Zhang, Jianbo Dai, Guangyuan Weng

“…However, it also exhibits excellent ductility of the coupling beams, which is necessary for dissipating energy under infrequent earthquakes. Subsequently, nonlinear hysteretic analyses are conducted from finite element analysis software ABAQUS, and a parametric study based on the finite element technique is performed to identify the optimal value of the coupling ratio. …”
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Constructing the Fuzzy Hyperbola and Its Applications in Analytical Fuzzy Plane Geometry by Seçil Özekinci, Cansel Aycan

“…In addition, finding the membership of a given point to the fuzzy hyperbola is possible by solving nonlinear equations under different angular approaches. …”
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Study on predictive models for COVID-19 in Cuba by Juan Felipe Medina Mendieta, Manuel Eduardo Cortés Cortés, Manuel Cortés Iglesias, Annia del Carmen Pérez Fernández, Marianelis Manzano Cabrera

“…<br /><strong>Methods:</strong> the least squares method was used to obtain the parameters using linear (MCL) and nonlinear (MCNL) models. Logistic and exponential models, such as the logistic growth curve, used to model population growth (Gompertz growth models), were applied to the growth prediction of infected cases and / or deaths, respectively.…”
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