The design of an antenna requires a careful selection of its parameters to retain the desired performance.However,this task is time-consuming when the traditional approaches are employed,which represents a significant...The design of an antenna requires a careful selection of its parameters to retain the desired performance.However,this task is time-consuming when the traditional approaches are employed,which represents a significant challenge.On the other hand,machine learning presents an effective solution to this challenge through a set of regression models that can robustly assist antenna designers to find out the best set of design parameters to achieve the intended performance.In this paper,we propose a novel approach for accurately predicting the bandwidth of metamaterial antenna.The proposed approach is based on employing the recently emerged guided whale optimization algorithm using adaptive particle swarm optimization to optimize the parameters of the long-short-term memory(LSTM)deep network.This optimized network is used to retrieve the metamaterial bandwidth given a set of features.In addition,the superiority of the proposed approach is examined in terms of a comparison with the traditional multilayer perceptron(ML),Knearest neighbors(K-NN),and the basic LSTM in terms of several evaluation criteria such as root mean square error(RMSE),mean absolute error(MAE),and mean bias error(MBE).Experimental results show that the proposed approach could achieve RMSE of(0.003018),MAE of(0.001871),and MBE of(0.000205).These values are better than those of the other competing models.展开更多
In petroleum domain,optimizing hydrocarbon production is essential because it does not only ensure the economic prospects of the petroleum companies,but also fulfills the increasing global demand of energy.However,app...In petroleum domain,optimizing hydrocarbon production is essential because it does not only ensure the economic prospects of the petroleum companies,but also fulfills the increasing global demand of energy.However,applying numerical reservoir simulation(NRS)to optimize production can induce high computational footprint.Proxy models are suggested to alleviate this challenge because they are computationally less demanding and able to yield reasonably accurate results.In this paper,we demonstrated how a machine learning technique,namely long short-term memory(LSTM),was applied to develop proxies of a 3D reservoir model.Sampling techniques were employed to create numerous simulation cases which served as the training database to establish the proxies.Upon blind validating the trained proxies,we coupled these proxies with particle swarm optimization to conduct production optimization.Both training and blind validation results illustrated that the proxies had been excellently developed with coefficient of determination,R2 of 0.99.We also compared the optimization results produced by NRS and the proxies.The comparison recorded a good level of accuracy that was within 3%error.The proxies were also computationally 3 times faster than NRS.Hence,the proxies have served their practical purposes in this study.展开更多
Physiological signal based biometric analysis has recently attracted attention as a means of meeting increasing privacy and security requirements.The real-time nature of an electrocardiogram(ECG)and the hidden nature ...Physiological signal based biometric analysis has recently attracted attention as a means of meeting increasing privacy and security requirements.The real-time nature of an electrocardiogram(ECG)and the hidden nature of the information make it highly resistant to attacks.This paper focuses on three major bottlenecks of existing deep learning driven approaches:the lengthy time requirements for optimizing the hyperparameters,the slow and computationally intense identification process,and the unstable and complicated nature of ECG acquisition.We present a novel deep neural network framework for learning human identification feature representations directly from ECG time series.The proposed framework integrates deep bidirectional long short-term memory(BLSTM)and adaptive particle swarm optimization(APSO).The overall approach not only avoids the inefficient and experience-dependent search for hyperparameters,but also fully exploits the spatial information of ordinal local features and the memory characteristics of a recognition algorithm.The effectiveness of the proposed approach is thoroughly evaluated in two ECG datasets,using two protocols,simulating the influence of electrode placement and acquisition sessions in identification.Comparing four recurrent neural network structures and four classical machine learning and deep learning algorithms,we prove the superiority of the proposed algorithm in minimizing overfitting and self-learning of time series.The experimental results demonstrated an average identification rate of 97.71%,99.41%,and 98.89% in training,validation,and test sets,respectively.Thus,this study proves that the application of APSO and LSTM techniques to biometric human identification can achieve a lower algorithm engineering effort and higher capacity for generalization.展开更多
双有源桥变换器因其优异的功率密度和双向功率传输能力,在众多工业应用中得到广泛关注。随着电力电子设备对能效和可靠性要求的不断提高,双有源桥变换器的电流应力已成为衡量其性能的关键指标之一。过大的电流应力不仅会导致功率器件损...双有源桥变换器因其优异的功率密度和双向功率传输能力,在众多工业应用中得到广泛关注。随着电力电子设备对能效和可靠性要求的不断提高,双有源桥变换器的电流应力已成为衡量其性能的关键指标之一。过大的电流应力不仅会导致功率器件损耗增加,系统效率下降,还会影响变换器的可靠性和使用寿命。针对上述问题,提出了一种基于TabNet-LN-LSTM协同预测与粒子群优化的电流应力优化方法。该方法通过利用TabNet和层归一化长短期记忆神经网络(Long-short term memory neural network with layer normalization,LN-LSTM)协同构建电感电流时序预测模型,并结合粒子群优化算法对双有源桥变换器在不同运行工况下的电流应力进行优化。通过算法试验和硬件试验证明,所提方法不仅能够精确预测电感电流波形,其预测波形与硬件实测波形相比,其平均绝对误差仅为0.3525,决定系数高达97.17%;同时,能够有效降低双有源桥变换器的电流应力,进一步提升系统的整体效能和可靠性。展开更多
文摘The design of an antenna requires a careful selection of its parameters to retain the desired performance.However,this task is time-consuming when the traditional approaches are employed,which represents a significant challenge.On the other hand,machine learning presents an effective solution to this challenge through a set of regression models that can robustly assist antenna designers to find out the best set of design parameters to achieve the intended performance.In this paper,we propose a novel approach for accurately predicting the bandwidth of metamaterial antenna.The proposed approach is based on employing the recently emerged guided whale optimization algorithm using adaptive particle swarm optimization to optimize the parameters of the long-short-term memory(LSTM)deep network.This optimized network is used to retrieve the metamaterial bandwidth given a set of features.In addition,the superiority of the proposed approach is examined in terms of a comparison with the traditional multilayer perceptron(ML),Knearest neighbors(K-NN),and the basic LSTM in terms of several evaluation criteria such as root mean square error(RMSE),mean absolute error(MAE),and mean bias error(MBE).Experimental results show that the proposed approach could achieve RMSE of(0.003018),MAE of(0.001871),and MBE of(0.000205).These values are better than those of the other competing models.
文摘In petroleum domain,optimizing hydrocarbon production is essential because it does not only ensure the economic prospects of the petroleum companies,but also fulfills the increasing global demand of energy.However,applying numerical reservoir simulation(NRS)to optimize production can induce high computational footprint.Proxy models are suggested to alleviate this challenge because they are computationally less demanding and able to yield reasonably accurate results.In this paper,we demonstrated how a machine learning technique,namely long short-term memory(LSTM),was applied to develop proxies of a 3D reservoir model.Sampling techniques were employed to create numerous simulation cases which served as the training database to establish the proxies.Upon blind validating the trained proxies,we coupled these proxies with particle swarm optimization to conduct production optimization.Both training and blind validation results illustrated that the proxies had been excellently developed with coefficient of determination,R2 of 0.99.We also compared the optimization results produced by NRS and the proxies.The comparison recorded a good level of accuracy that was within 3%error.The proxies were also computationally 3 times faster than NRS.Hence,the proxies have served their practical purposes in this study.
基金Project supported by the Zhejiang Province Public Welfare Technology Application Research Project(No.LGG20F010008)the National Natural Science Foundation of China(No.61571173)the Welfare Project of the Science Technology Department of Zhejiang Province,China(No.LGG18F010012)。
文摘Physiological signal based biometric analysis has recently attracted attention as a means of meeting increasing privacy and security requirements.The real-time nature of an electrocardiogram(ECG)and the hidden nature of the information make it highly resistant to attacks.This paper focuses on three major bottlenecks of existing deep learning driven approaches:the lengthy time requirements for optimizing the hyperparameters,the slow and computationally intense identification process,and the unstable and complicated nature of ECG acquisition.We present a novel deep neural network framework for learning human identification feature representations directly from ECG time series.The proposed framework integrates deep bidirectional long short-term memory(BLSTM)and adaptive particle swarm optimization(APSO).The overall approach not only avoids the inefficient and experience-dependent search for hyperparameters,but also fully exploits the spatial information of ordinal local features and the memory characteristics of a recognition algorithm.The effectiveness of the proposed approach is thoroughly evaluated in two ECG datasets,using two protocols,simulating the influence of electrode placement and acquisition sessions in identification.Comparing four recurrent neural network structures and four classical machine learning and deep learning algorithms,we prove the superiority of the proposed algorithm in minimizing overfitting and self-learning of time series.The experimental results demonstrated an average identification rate of 97.71%,99.41%,and 98.89% in training,validation,and test sets,respectively.Thus,this study proves that the application of APSO and LSTM techniques to biometric human identification can achieve a lower algorithm engineering effort and higher capacity for generalization.
文摘双有源桥变换器因其优异的功率密度和双向功率传输能力,在众多工业应用中得到广泛关注。随着电力电子设备对能效和可靠性要求的不断提高,双有源桥变换器的电流应力已成为衡量其性能的关键指标之一。过大的电流应力不仅会导致功率器件损耗增加,系统效率下降,还会影响变换器的可靠性和使用寿命。针对上述问题,提出了一种基于TabNet-LN-LSTM协同预测与粒子群优化的电流应力优化方法。该方法通过利用TabNet和层归一化长短期记忆神经网络(Long-short term memory neural network with layer normalization,LN-LSTM)协同构建电感电流时序预测模型,并结合粒子群优化算法对双有源桥变换器在不同运行工况下的电流应力进行优化。通过算法试验和硬件试验证明,所提方法不仅能够精确预测电感电流波形,其预测波形与硬件实测波形相比,其平均绝对误差仅为0.3525,决定系数高达97.17%;同时,能够有效降低双有源桥变换器的电流应力,进一步提升系统的整体效能和可靠性。