Article
Acoustics
Holger Waubke, Christian H. Kasess
Summary: Gaussian closure is used to calculate the behavior of chain-like structures with hysteretic elements under white noise excitation, resulting in analytic expressions for the temporal evolution of the statistical moments. The method is generalized to the case of a filtered white noise with a slowly varying intensity, which is relevant in earthquake scenarios. The model is further complex when there is a lack of elastic restoring force at the hysteretic node that couples the tank model with the surface.
JOURNAL OF LOW FREQUENCY NOISE VIBRATION AND ACTIVE CONTROL
(2023)
Article
Engineering, Mechanical
Takahiro Tsuchida, Koji Kimura
Summary: This paper presents an approximate analytical method to obtain the stationary response probability density and mean upcrossing rate for a linear system under non-Gaussian random excitation. The method first utilizes the equivalent non-Gaussian excitation method to derive a closed set of moment equations for the system response, and then calculates the exact solutions of response moments up to the fourth order from these equations. The proposed method demonstrates its effectiveness by comparing the analytical results with Monte Carlo simulation results for linear systems under random excitations with different probability densities.
PROBABILISTIC ENGINEERING MECHANICS
(2023)
Article
Engineering, Multidisciplinary
Armin Tabandeh, Neetesh Sharma, Leandro Iannacone, Paolo Gardoni
Summary: This paper presents a novel numerical method based on physics-based mixture models for solving the transient and steady-state solutions of the Fokker-Planck equation. The unknown parameters of the mixture model are estimated using Bayesian inference with constraints on model parameters. An importance sampling algorithm is developed to reduce computational demand. The performance of the proposed method is demonstrated with benchmark problems.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
Article
Engineering, Civil
Yexiang Yan, Hongwei Huang, Limin Sun
Summary: This paper proposes a parameterized method for component and system-level fragility analysis through multivariate seismic fragility analysis. The study demonstrates that compared to existing methods, the proposed approach can efficiently and accurately generate multivariate fragility functions, and provides optimal choices for sample size, surrogate model, and IM selection.
ENGINEERING STRUCTURES
(2022)
Article
Acoustics
V. Tyrode, N. Totaro, L. Maxit, A. Le Bot
Summary: This article discusses the necessity and validity of the assumption of diffuse field in statistical energy analysis, as well as the coupling power proportionality which states that the vibrational power exchanged between coupled subsystems is proportional to the difference of their modal energies. It proposes a reformulation of the coupling power proportionality in terms of local energy density instead of modal energy. The generalized form is shown to remain valid even if the vibrational field is not diffuse. Various causes of lack of diffuseness are studied, and numerical simulations and experimental results on flexural vibration of flat plates are provided to support the statements made.
JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA
(2023)
Review
Engineering, Aerospace
Ronghui Zheng, Guoping Chen, Huaihai Chen
Summary: This paper reviews various methods for controlling stationary non-Gaussian random vibration, discussing how to control time and frequency domain characteristics in non-Gaussian random vibration tests and generate a one frame stationary non-Gaussian random signal.
CHINESE JOURNAL OF AERONAUTICS
(2021)
Article
Engineering, Multidisciplinary
Xiangqian Sheng, Wenliang Fan
Summary: This paper presents a practical calculation method for high-order moment spectra models of quadratic Gaussian stochastic processes. The expressions for the first four moment spectra of quadratic Gaussian stochastic processes are derived based on the relation between the high-order cumulant function and high-order moment function. The proposed method calculates the high-order moment spectra using the ratio of the corresponding component moment functions, and its efficiency and accuracy are validated through numerical examples.
APPLIED MATHEMATICAL MODELLING
(2023)
Article
Engineering, Electrical & Electronic
Jianjun Sun, Yan Zhao, Shigang Wang, Jian Wei
Summary: This paper introduces a Gaussian Mixture Model (GMM) constrained by Markov Random Field (MRF) framework for image compression, optimizing parameters selection with adjusted Expectation-Maximization (EM) algorithm and Mixture Model Optimization (MMO). The method encodes parameters using fixed-length bits and uses a codebook to improve efficiency, with the residual encoded using HEVC intra coding. Experimental results demonstrate superior performance compared to HEVC, JPEG 2000, and BPG.
Article
Environmental Sciences
Andras Bardossy, Sebastian Horning
Summary: The spatial structures of natural variables are often complex and exhibit non-Gaussian spatial dependence. Existing approaches to consider non-Gaussian behavior are limited. This study presents a flexible method for defining non-Gaussian spatial dependence, based on continuous deformation of fields with different Gaussian spatial dependence. The methodology is illustrated with theoretical examples and demonstrated in a real-life example of groundwater quality parameters.
WATER RESOURCES RESEARCH
(2023)
Article
Engineering, Mechanical
Wenliang Fan, Xiangqian Sheng, Zhengliang Li, Yi Sun
Summary: The study presents a novel high-order statistical analysis method for effectively analyzing vibrations of structures under non-Gaussian excitation, which is more comprehensive compared to conventional methods. An analytical solution for higher-order statistics of response was derived using the mode superposition method, along with a theoretical expression for calculating higher-order moment spectrum of response.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2022)
Article
Computer Science, Information Systems
Zhi Li, Lei Liu, Jiaqiang Wang, Li Lin, Jichang Dong, Zhi Dong
Summary: In this paper, a Multi-Barriers Model is proposed to characterize an area of interest with different types of obstacles. The proposed model divides the area into sub-areas, one with sampling points and the other with obstacles. The correlation between points is determined by the obstruction degree of the obstacles, and stochastic partial differential equations are used to express continuous Gaussian fields. The model is verified using geostatistical and log-Gaussian Cox models, and its performance is compared with other models using real burglary data. The Multi-Barriers Model is found to better interpret spatial models with multiple obstacles and is closer to reality.
Article
Engineering, Mechanical
Ronghui Zheng, Guoping Chen, Huaihai Chen
Summary: An innovative power spectrum and kurtosis separation control strategy is proposed for non-Gaussian random vibration test, aiming to address the practical situation where spectrum and kurtosis control channels are not completely coincident. The feasibility of the proposed control method is verified through simulation examples and biaxial separation and non-separation non-Gaussian random vibration tests.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2022)
Article
Mathematics, Applied
Ruo Li, Weiming Li, Lingchao Zheng
Summary: A new closure approach is proposed in this paper, which approximates the flux gradient instead of the flux function, providing significant advantages over the canonical approach. This method allows for deriving globally hyperbolic moment models while preserving conservative variables in low order moments.
SIAM JOURNAL ON APPLIED MATHEMATICS
(2021)
Article
Computer Science, Artificial Intelligence
Muhammad Hameed Siddiqi
Summary: This study focuses on improving the emotional speech classifier by introducing a novel methodology to address the limitations of existing classifiers, achieving significant improvement in emotional recognition. The proposed method has been validated and evaluated on two datasets, showing significantly improved classification performance. In terms of computation, the technique is also more cost-effective compared to state of the art works.
EGYPTIAN INFORMATICS JOURNAL
(2021)
Article
Computer Science, Interdisciplinary Applications
Juntao Huang, Yingda Cheng, Andrew J. Christlieb, Luke F. Roberts
Summary: In this paper, a data-driven approach using machine learning is applied to solve the moment closure problem for the radiative transfer equation in slab geometry. Instead of learning the unclosed high order moment, the gradient of the high order moment is directly learned using neural networks. This new approach is consistent with the exact closure for the free streaming limit and provides a natural output normalization. Various benchmark tests confirm the accuracy and generalizability of the machine learning closure model.
JOURNAL OF COMPUTATIONAL PHYSICS
(2022)
Article
Engineering, Mechanical
R. Allahvirdizadeh, A. Andersson, R. Karoumi
Summary: The operational safety of high-speed trains on ballasted bridges relies on preventing ballast destabilization. This study explores the impact of epistemic uncertainties on the system using ISRA. Neglecting these uncertainties can lead to overestimation of permissible train speeds and reduced system safety.
PROBABILISTIC ENGINEERING MECHANICS
(2024)
Article
Engineering, Mechanical
Lujie Shi, Leila Khalij, Christophe Gautrelet, Chen Shi, Denis Benasciutti
Summary: This study proposes an innovative Two-phase method based on the Langlie method and the D-optimality criterion to overcome the intrinsic shortcomings of the staircase method used in estimating the fatigue limit distribution. Through simulation-based study, it is demonstrated that the proposed method improves the estimation performance for the mean and standard deviation of the fatigue limit distribution.
PROBABILISTIC ENGINEERING MECHANICS
(2024)
Article
Engineering, Mechanical
Axay Thapa, Atin Roy, Subrata Chakraborty
Summary: This article compares different metamodeling approaches for reliability analysis of tunnels to evaluate their performance. The study found that Kriging and support vector regression models perform well in estimating the reliability of underground tunnels.
PROBABILISTIC ENGINEERING MECHANICS
(2024)
Article
Engineering, Mechanical
Jiaqi Wang, Zhenzhou Lu, Lu Wang
Summary: This paper proposes an efficient method to estimate the FP-GS using reliability updating, avoiding the time-consuming double-loop structure analysis. By utilizing the likelihood function and adaptive Kriging model, the unconditional FP and all conditional FPs can be estimated simultaneously.
PROBABILISTIC ENGINEERING MECHANICS
(2024)
Article
Engineering, Mechanical
Jiaxu Li, Ming Liu, Xu Yan, Qianting Yang
Summary: Wind pressure is essential for architectural design, and this study found that using different probabilistic distribution models can improve the accuracy of reference wind pressure calculation. In the research conducted in Liaoning Province, the extreme value type III model and moment method achieved the best fit. Additionally, probability density functions for wind speed and wind direction were established for further analysis of wind pressure.
PROBABILISTIC ENGINEERING MECHANICS
(2024)
Article
Engineering, Mechanical
Yufan Cheng, Xinchen Zhuang, Tianxiang Yu
Summary: This paper proposes a time-dependent kinematic reliability analysis method that takes into account the truncated random variables and joint clearances, effectively addressing the issues of dimension variables and correlation between joint clearance variables. The proposed method transforms time-dependent reliability into time-independent reliability, greatly reducing computational complexity and obtaining upper and lower bounds of failure probability.
PROBABILISTIC ENGINEERING MECHANICS
(2024)