Applied Mathematics

Bearing fault diagnosis based on multi-scale spectral images and convolutional neural network
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Research Article
Bearing fault diagnosis based on multi-scale spectral images and convolutional neural network
By Tongchao Luo, Mingquan Qiu, Zhenyu Wu, Zebo Zhao, Dingyou Zhang
To address the challenges of poor performance in traditional diagnosis methods and two-dimensional (2-D) feature based approaches, this paper proposes a novel fault diagnosis approach based on multi-scale spectrum feature images and deep learning. Firstly, the vibration signal is preprocessed through mean removal processing and then converted to multi-length spectrum with fast Fourier transform (FFT). Secondly, a novel 2-D feature called multi-scale spectral image (MSSI) is constructed by multi-length spectrum paving scheme. Finally, a deep learning framework, convolutional neural network (CNN), is formulated to diagnose the bearing faults. Two experimental cases are utilized to verify the effectiveness of the proposed method. Experimental results demonstrate that the proposed method significantly improves the accuracy of fault diagnosis.
August 24, 2025
Applied Mathematics
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Research Article
Fault diagnosis and health management of bearings in rotating equipment based on vibration analysis – a review
By Adnan Althubaiti, Faris Elasha, Joao Amaral Teixeira
November 26, 2021
Applied Mathematics
Most cited
Research Article
A convolutional neural network method based on Adam optimizer with power-exponential learning rate for bearing fault diagnosis
By Youming Wang, Zhao Xiao, Gongqing Cao
June 30, 2022
Applied Mathematics
Most cited
Research Article
A review on wind turbines gearbox fault diagnosis methods
By H. Gu, W. Y. Liu, Q. W. Gao, Y. Zhang
January 27, 2021
Applied Mathematics
Most cited
Research Article
Bearing fault diagnosis based on improved VMD and DCNN
By Ran Wang, Lei Xu, Fengkai Liu
August 15, 2020
Applied Mathematics

Mathematical Models in Engineering

Optimization and modelling of mahua oil biodiesel using RSM and genetic algorithm techniques
Research Article
Optimization and modelling of mahua oil biodiesel using RSM and genetic algorithm techniques
In this present investigation, four important process parameters of catalyst concentration, molar ratio, reaction time, and reaction temperature were studied and optimized using Box Behnken assisted response surface method (RSM) and Genetic Algorithm (GA) to achieve the maximum mahua oil biodiesel yield. For this purpose, 27 experiments were conducted randomly based on the design matrix using statistical software MiniTab®2019. A maximum yield of 91.32 % is achieved in RSM, catalyst concentration and reaction time are identified as influence parameters in biodiesel yield. GA modelling show an improvement of 4.96 % in biodiesel yield compared to RSM approach. Both techniques are successfully tested in prediction and modelling the biodiesel yield from mahua oil. The obtained biodiesel from the transesterification process is blended with standard diesel fuel at various proportions (B10 to B90) and tested for different fuel properties. All the biodiesel blends are observed within the limits of international standards of ASTMD-6751 and EN-14214. The results indicate that the chosen models are highly accurate in achieving maximum biodiesel yield and mahua biodiesel is recommended as the best alternative fuel to diesel engines without any major modifications in the engine design.
June 2, 2020
Informatics
Optimization of palm methyl ester and its effect on fatty acid compositions and cetane number
Research Article
Optimization of palm methyl ester and its effect on fatty acid compositions and cetane number
This paper proposes the Taguchi based optimization technique for the production of biodiesel from palm oil. For this purpose, L9 orthogonal array was successfully used for better yield estimation by using Minitab-18 software. Different process variables like molar ratio, catalyst concentration, reaction time and reaction temperature were studied. A predicted yield of 92.06 % was achieved by regression analysis by maintaining the process variables of molar ratio 5:1 (methanol to oil), 4 grams of catalyst concentration (NaOH), 180 minutes of reaction time and 44°C of reaction temperature. Experimentations were conducted on the same process variables and achieved a yield of 91.65 %. By this it is clear that both experimentation and regression analysis by Taguchi are in good agreement with an error of 0.41 % which may be acclaimed as experimental error. The fatty acid compositions (FAC) were also analyzed and it is found that 37.12 % saturated and 62.88 % unsaturated fatty acids present in the palm methyl ester (PME). By using the FAC of PME the Cetane number was predicted as 55.38. The predicted Cetane number from FAC tally with experimental Cetane number. The PME is characterized for different fuel properties by following the international standards. And it is concluded that catalyst concentration and reaction temperature are the important parameters which influence PME yield, Taguchi based optimization technique will helps in predicting the maximum yield with minimum number of experiments.
March 31, 2019
Informatics
Application of A* algorithm in intelligent vehicle path planning
Research Article
Application of A* algorithm in intelligent vehicle path planning
Path planning is one of the important directions in the field of intelligent vehicles research. Traditional path planning algorithms generally use Dijkstra algorithm, Breadth-First-Search (BFS) algorithm and A* algorithm. Dijkstra algorithm is a search-based algorithm, which can search to an optimal path, but the disadvantage is too many expansion nodes, which leads to insufficient search efficiency. BFS algorithm is a heuristic search algorithm, which reduces the disadvantage of too many expansion nodes and improves the search efficiency by heuristic function. A* algorithm is a heuristic search algorithm that combines Dijkstra’s algorithm and BFS algorithm, which has higher search efficiency and can search to an optimal path at the same time, but it is still lacking in the search mode and smoothness of the planned route. This paper first introduces the general path planning algorithm, then introduces and analyzes the A* algorithm, and proposes improvement measures for its shortcomings; finally, the executability and effectiveness of the improved algorithm are tested using simulation, and compared with the traditional A* algorithm, and the results show that the improved A* algorithm has good effect on path planning of intelligent vehicles.
August 17, 2022
Informatics
Performance of PID-Fuzzy control for cab isolation mounts of soil compactors
Research Article
Performance of PID-Fuzzy control for cab isolation mounts of soil compactors
To improve the soil compactor ride comfort, a combined control method of Fuzzy and PID control is proposed to control the cab isolation system of soil compactor based on the non-linear vehicle dynamic model. The vibration excitation sources are concerned by the vibrator drum and elastoplastic soil (EPS) interactions in the compression process. The power-spectral-density (PSD) and weighted root-mean-square (RMS) of acceleration responses of both the vertical driver’s seat and pitching cab angle are chosen as the objective functions. The research results show that both the PSD and weighted RMS values of the vertical driver’s seat and pitching cab angle are significantly reduced by using the PID-Fuzzy control under various EPSs in the low-frequency region, especially on the EPS with high-density.
December 31, 2019
Informatics
Mathematical Models in Engineering
<p>Mathematical results and models specifically applicable to engineering science, technology, and their practical applications across various disciplines</p>
CiteScore
1.4
APC
350 EUR

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