Accurate prediction of hydrocarbon production is crucial for the oil and gas industry. However, the strong heterogeneity of underground formation, the inconsistency in oil-gas-water distribution, and the complex flow ...
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Accurate prediction of hydrocarbon production is crucial for the oil and gas industry. However, the strong heterogeneity of underground formation, the inconsistency in oil-gas-water distribution, and the complex flow mechanisms make hydrocarbon production forecasting (HPF) difficult, which leads to a high level of uncertainty in the prediction results. The explosion of machine learning (ML) methodologies that are capable of analyzing big data shed new light on HPF using production data. In this article, an in-depth review is provided regarding HPF using ML methodologies. Firstly, the merits and drawbacks of traditional HPF methods are analyzed and summarized. Then, the applications of ML algorithms in HPF are reviewed in detail, especially concentrating on artificial neural network, support vector machine, and ensemble learning. For each algorithm, the basic theory and its variants are first introduced, and its applications in HPF are comprehensively demonstrated subsequently. Finally, this article presents the challenge and prospects of machine-learning-based HPF. Sophisticated ML proxy models can be con-structed and employed to deal with an extended type of input data such that improving the efficacy of data utilization. On the other hand, deep learning models designed to handle time-series data can gain more attention. Modeling approaches for multivariate time-series hydrocarbon production data using deep neural networks with similar functionality to LSTM may lead to more accurate and computationally efficient production forecasting.
The soil temperature affects the climate in a great manner and the soil temperature data can be used to make predictions about how the ecosystem is affected by heat or cold in global temperature. Various measurement t...
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The soil temperature affects the climate in a great manner and the soil temperature data can be used to make predictions about how the ecosystem is affected by heat or cold in global temperature. Various measurement techniques have been employed in analyzing the soil temperature. Among them, Artificial Neural Network (ANN) is used to perform mathematical formulation to learn patterns and relationships in the data. The present study provides a tool to predict the soil temperature for the year 2004 using random inputs taken between 1993 and 2003 under different cases at two different soil depths 10 cm and 20 cm using ANN. The analysis was carried out for both the annual and the seasonal waves. Thereby, heat gets depleted during the monsoon seasons and gets accumulated in the annual and the other season which help to study the atmospheric changes. The statistical validation of the predictions possesses an insignificant error when compared with that of the observed soil temperature. (c) 2021 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Conference on Advances in Materials Research-2019.
A new two-way parabolic equation (2W-PE) method is proposed in this paper which uses machine learning to determine boundary condition equations, and accurately predicts the electromagnetic field strength distribution ...
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A new two-way parabolic equation (2W-PE) method is proposed in this paper which uses machine learning to determine boundary condition equations, and accurately predicts the electromagnetic field strength distribution in the environment of media ground and obstacles. On the basis of previous researches, the obstacle area is decomposed according to the principle of domain decomposition, and the processes of solving 2W-PE in each subdomain are briefly explained. Because the direction and strength of the incident waves on the boundaries vary greatly with the propagation environment, it is difficult for us to determine boundary condition equations. The machine learning method is introduced here, and method of moments (MoM) is applied to generate sample data sets, thus, coefficients in boundary condition equations can be trained through the non-end-to-end neural network combined with backpropagationalgorithm and gradient descent method. So that no matter how the environment changes, appropriate boundary conditions can be obtained by the well-trained neural network and help improving the accuracy of 2W-PE. Simulation results show that the accuracy of the new 2W-PE method based on machine learning is better than that of 2W-PE with traditional boundary conditions by comparing with the results of MoM, which also reflects the advantages of machine learning in radio wave propagation analysis. Therefore, this paper provides an innovative and reliable method for accurately predicting field distribution in flat-top obstacle environments.
The battery is the key element to store and then supply electricity to the various components of Electric Vehicles (EV). However, the battery cannot be charged and discharged indefinitely. The main objective of this s...
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ISBN:
(纸本)9781665422581
The battery is the key element to store and then supply electricity to the various components of Electric Vehicles (EV). However, the battery cannot be charged and discharged indefinitely. The main objective of this study is to develop a novel methodology for estimation of the ageing rate of a Lithium-Fer-Phosphate (LFP) battery used in electric vehicles in order to predict its Remaining Useful Life (RUL). Indeed, a new method based a modified version of neural networks is proposed. It is used to estimate the LFP battery's Discharge Capacity (DC) and to conclude about the battery's end of life.
The present paper aims to propose an approximation method of Caputo fractional operator using discretization based on quadrature theory to minimize the error function for an Artificial Neural Network (ANN) with higher...
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It is important to locate the fault distance and identify the fault types quickly, take effective measures to maintain line stability, and minimize the losses timely when there are short-circuit faults in transmission...
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It is important to locate the fault distance and identify the fault types quickly, take effective measures to maintain line stability, and minimize the losses timely when there are short-circuit faults in transmission lines. For this purpose, a method based on deep learning is proposed for short-circuit faults identification in the transmission line. According to the similarity of samples in the reconstruction phase, a minimum neighborhood sample set is selected from the massive samples firstly, and then, the samples are trained using the back propagation algorithm along time in a recurrent neural network (RNN) with long-short term memory (LSTM) units. Compared with existing algorithms, the experimental results show that this algorithm meets the requirements of rapid fault diagnosis in the case of variable parameters, and higher fault type recognition accuracy and lower fault distance error can be obtained.
How to design deep neural networks (DNNs) for the representation and analysis of high dimensional but small sample size data is still a big challenge. One solution is to construct a sparse network. At present, there e...
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How to design deep neural networks (DNNs) for the representation and analysis of high dimensional but small sample size data is still a big challenge. One solution is to construct a sparse network. At present, there exist many approaches to achieve sparsity for DNNs by regularization, but most of them are carried out only in the pre-training process due to the difficulty in the derivation of explicit formulae in the fine-tuning process. In this paper, a log-sum function is used as the regularization terms for both the responses of hidden neurons and the network connections in the loss function of the fine-tuning process. It provides a better approximation to the L-0-norm than several often used norms. Based on the gradient formula of the loss function, the fine-tuning process can be executed more efficiently. Specifically, the commonly used gradient calculation in many deep learning research platforms, such as PyTorch or TensorFlow, can be accelerated. Given the analytic formula for calculating gradients used in any layer of DNN, the error accumulated from successive numerical approximations in the differentiation process can be avoided. With the proposed log-sum enhanced sparse deep neural network (LSES-DNN), the spar-sity of the responses and the connections can be well controlled to improve the adaptivity of DNNs. The proposed model is applied to MRI data for both the diagnosis of schizophrenia and the study of brain developments. Numerical experiments demonstrate its superior performance among several classical classifiers tested. (C) 2020 Elsevier B.V. All rights reserved.
In this study, the results of the work distribution made with the TOPSIS method, which is frequently used in the distribution of work to the subcontractor workshops, were estimated using the Artificial Neural Networks...
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In this study, the results of the work distribution made with the TOPSIS method, which is frequently used in the distribution of work to the subcontractor workshops, were estimated using the Artificial Neural Networks Method (ANN). Here, the C* values used in the work distribution with the TOPSIS method were estimated by ANN. The correlation coefficient of the data obtained from the created model was found to be 99.99895% for learning. According to the results, it has been concluded that work distribution can be made by using the ANN method without making complex mathematical calculations in the distribution of work to the contract workshops.
Green energy sources are implemented for the generation of power due to their substantial advantages. Wind generation is the best among renewable options for power generation. Generally, the wind system is directly co...
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Green energy sources are implemented for the generation of power due to their substantial advantages. Wind generation is the best among renewable options for power generation. Generally, the wind system is directly connected with the power network for supplying power. In direct connection, there is an issue of managing power quality (PQ) concerns such as voltage sag, swells, flickers, harmonics, etc. In order to enhance the PQ in a power network with a wind energy conversion system (WECS), peripheral compensation is needed. In this paper, we highlight a novel control technique to improve the PQ in WECS by adopting an Artificial Neural Network (ANN)-based Distribution Static Compensator (DSTATCOM). In our proposed approach, an online learning-based ANN backpropagation (BP) model is used to generate the gate pulses of the DSTATCOM, which mitigate the harmonics at the grid side. It is modelled using the MATLAB platform and the total harmonic distortion (THD) of the system is compared with and without DSTATCOM. The harmonics at the source side decreased to less than 5% and are within the IEEE limits. The results obtained reveal that the proposed online learning-based ANN-BP is superior in nature.
The miniature revolving heat pipes (MRVHPs) are promising candidates for the cooling structure design of rotating machines, however, the relation between the thermal performance of MRVHPs and their thermo-physical pro...
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The miniature revolving heat pipes (MRVHPs) are promising candidates for the cooling structure design of rotating machines, however, the relation between the thermal performance of MRVHPs and their thermo-physical properties is still absent. Therefore, MRVHPs are tested in various operational conditions firstly. And then, a power-law empirical correlation is developed based on experimental data, Ku, Ja, Pr, Bo and Fr are determined as main effective dimensionless parameters, phi while the structural parameters of MRVHPs D-i/R, L-e/L-c, L-e/L-eff and filling ratio yo are considered as well. However, the prediction accuracy is not satisfactory enough. Considering ANNs have been widely used in varied applications and demonstrated to be particularly credible in system modeling and identification, therefore, a BPNN model which parameterized by GA is developed for thermal performance prediction of the MRVHPs. The experimental data are divided into training data set and testing data set. Ja, Pr, Bo, Fr and phi are regarded as inputs, while Ku is output. The results show that the established GA-BPNN model could predict thermal performance of MRVHPs with a very good accuracy. Comparing with the predicted results of semi-empirical correlation, the square of correlation coefficient (R-2) is increased by 13.265%. Meanwhile, the evaluation method for the optimal filling ratio of the MRVHPs under specified working conditions is developed and an acceptable accuracy is obtained. (C) 2020 Published by Elsevier Ltd.
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