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A Denoiser for Correlated Noise Channel Decoding: Gated-Neural Network
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作者 Xiao Li Ling Zhao +1 位作者 Zhen Dai Yonggang Lei 《China Communications》 SCIE CSCD 2024年第2期122-128,共7页
This letter proposes a sliced-gated-convolutional neural network with belief propagation(SGCNN-BP) architecture for decoding long codes under correlated noise. The basic idea of SGCNNBP is using Neural Networks(NN) to... This letter proposes a sliced-gated-convolutional neural network with belief propagation(SGCNN-BP) architecture for decoding long codes under correlated noise. The basic idea of SGCNNBP is using Neural Networks(NN) to transform the correlated noise into white noise, setting up the optimal condition for a standard BP decoder that takes the output from the NN. A gate-controlled neuron is used to regulate information flow and an optional operation—slicing is adopted to reduce parameters and lower training complexity. Simulation results show that SGCNN-BP has much better performance(with the largest gap being 5dB improvement) than a single BP decoder and achieves a nearly 1dB improvement compared to Fully Convolutional Networks(FCN). 展开更多
关键词 belief propagation channel decoding correlated noise neural network
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Study on analytical noise propagation in convolutional neural network methods used in computed tomography imaging 被引量:7
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作者 Xiao-Yue Guo Li Zhang Yu-Xiang Xing 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第6期114-127,共14页
Neural network methods have recently emerged as a hot topic in computed tomography(CT) imaging owing to their powerful fitting ability;however, their potential applications still need to be carefully studied because t... Neural network methods have recently emerged as a hot topic in computed tomography(CT) imaging owing to their powerful fitting ability;however, their potential applications still need to be carefully studied because their results are often difficult to interpret and are ambiguous in generalizability. Thus, quality assessments of the results obtained from a neural network are necessary to evaluate the neural network. Assessing the image quality of neural networks using traditional objective measurements is not appropriate because neural networks are nonstationary and nonlinear. In contrast, subjective assessments are trustworthy, although they are time-and energy-consuming for radiologists. Model observers that mimic subjective assessment require the mean and covariance of images, which are calculated from numerous image samples;however, this has not yet been applied to the evaluation of neural networks. In this study, we propose an analytical method for noise propagation from a single projection to efficiently evaluate convolutional neural networks(CNNs) in the CT imaging field. We propagate noise through nonlinear layers in a CNN using the Taylor expansion. Nesting of the linear and nonlinear layer noise propagation constitutes the covariance estimation of the CNN. A commonly used U-net structure is adopted for validation. The results reveal that the covariance estimation obtained from the proposed analytical method agrees well with that obtained from the image samples for different phantoms, noise levels, and activation functions, demonstrating that propagating noise from only a single projection is feasible for CNN methods in CT reconstruction. In addition, we use covariance estimation to provide three measurements for the qualitative and quantitative performance evaluation of U-net. The results indicate that the network cannot be applied to projections with high noise levels and possesses limitations in terms of efficiency for processing low-noise projections. U-net is more effective in improving the image quality of smooth regions compared with that of the edge. LeakyReLU outperforms Swish in terms of noise reduction. 展开更多
关键词 Noise propagation Convolutional neural network Image quality assessment
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基于PCA-BPNN的桥梁爆炸荷载时程预测
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作者 杜晓庆 何益平 +2 位作者 邱涛 程帅 张德志 《爆炸与冲击》 北大核心 2025年第3期77-91,共15页
人工智能方法是预测爆炸荷载的新手段,但现有方法主要用于预测爆炸冲击波的超压峰值或冲量,而用于预测反射超压时程的研究不多。针对这一问题,以平面冲击波绕射桥梁主梁为对象,提出了一种基于主成分分析(principal components analysis,... 人工智能方法是预测爆炸荷载的新手段,但现有方法主要用于预测爆炸冲击波的超压峰值或冲量,而用于预测反射超压时程的研究不多。针对这一问题,以平面冲击波绕射桥梁主梁为对象,提出了一种基于主成分分析(principal components analysis,PCA)和误差反向传播神经网络(backpropagation neural network,BPNN)的桥梁爆炸冲击波反射超压时程预测模型。该预测模型利用PCA降维处理时程数据,基于多任务学习的BPNN算法,提出了考虑超压峰值和冲量峰值影响的损失函数,使模型能有效预测不同入射超压下的桥梁冲击波荷载时程。通过分析多任务学习模型、多输入单输出模型和多输入多输出模型等3种BPNN模型,发现多任务学习模型的预测精度最高,而多输入多输出模型难以有效适应当前预测任务需求。采用多任务学习模型预测得到的桥梁表面各测点位置的反射超压时程、超压峰值精度较高,决定系数R2分别为0.792和0.987,作用在箱梁上的合力时程和扭矩时程预测值也与数值模拟值较为吻合。同时,该模型对内插值预测的表现优于外推值预测,但其在预测外推值方面同样展现出了一定的能力。 展开更多
关键词 爆炸荷载预测 反射超压时程 误差反向传播神经网络 主成分分析 多任务学习
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DDoS Attack Detection Scheme Based on Entropy and PSO-BP Neural Network in SDN 被引量:8
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作者 Zhenpeng Liu Yupeng He +1 位作者 Wensheng Wang Bin Zhang 《China Communications》 SCIE CSCD 2019年第7期144-155,共12页
SDN (Software Defined Network) has many security problems, and DDoS attack is undoubtedly the most serious harm to SDN architecture network. How to accurately and effectively detect DDoS attacks has always been a diff... SDN (Software Defined Network) has many security problems, and DDoS attack is undoubtedly the most serious harm to SDN architecture network. How to accurately and effectively detect DDoS attacks has always been a difficult point and focus of SDN security research. Based on the characteristics of SDN, a DDoS attack detection method combining generalized entropy and PSOBP neural network is proposed. The traffic is pre-detected by the generalized entropy method deployed on the switch, and the detection result is divided into normal and abnormal. Locate the switch that issued the abnormal alarm. The controller uses the PSO-BP neural network to detect whether a DDoS attack occurs by further extracting the flow features of the abnormal switch. Experiments show that compared with other methods, the detection accurate rate is guaranteed while the CPU load of the controller is reduced, and the detection capability is better. 展开更多
关键词 software-defined networkING distributed DENIAL of service ATTACKS generalized information ENTROPY particle SWARM optimization back propagation neural network ATTACK detection
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Labeling Malicious Communication Samples Based on Semi-Supervised Deep Neural Network 被引量:2
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作者 Guolin Shao Xingshu Chen +1 位作者 Xuemei Zeng Lina Wang 《China Communications》 SCIE CSCD 2019年第11期183-200,共18页
The limited labeled sample data in the field of advanced security threats detection seriously restricts the effective development of research work.Learning the sample labels from the labeled and unlabeled data has rec... The limited labeled sample data in the field of advanced security threats detection seriously restricts the effective development of research work.Learning the sample labels from the labeled and unlabeled data has received a lot of research attention and various universal labeling methods have been proposed.However,the labeling task of malicious communication samples targeted at advanced threats has to face the two practical challenges:the difficulty of extracting effective features in advance and the complexity of the actual sample types.To address these problems,we proposed a sample labeling method for malicious communication based on semi-supervised deep neural network.This method supports continuous learning and optimization feature representation while labeling sample,and can handle uncertain samples that are outside the concerned sample types.According to the experimental results,our proposed deep neural network can automatically learn effective feature representation,and the validity of features is close to or even higher than that of features which extracted based on expert knowledge.Furthermore,our proposed method can achieve the labeling accuracy of 97.64%~98.50%,which is more accurate than the train-then-detect,kNN and LPA methodsin any labeled-sample proportion condition.The problem of insufficient labeled samples in many network attack detecting scenarios,and our proposed work can function as a reference for the sample labeling tasks in the similar real-world scenarios. 展开更多
关键词 sample LABELING MALICIOUS COMMUNICATION SEMI-SUPERVISED learning DEEP neural network LABEL propagation
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Artificial neural network approach for rheological characteristics of coal-water slurry using microwave pre-treatment 被引量:4
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作者 B.K.Sahoo S.De B.C.Meikap 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第2期379-386,共8页
Detailed experimental investigations were carried out for microwave pre-treatment of high ash Indian coal at high power level(900 W) in microwave oven. The microwave exposure times were fixed at60 s and 120 s. A rheol... Detailed experimental investigations were carried out for microwave pre-treatment of high ash Indian coal at high power level(900 W) in microwave oven. The microwave exposure times were fixed at60 s and 120 s. A rheology characteristic for microwave pre-treatment of coal-water slurry(CWS) was performed in an online Bohlin viscometer. The non-Newtonian character of the slurry follows the rheological model of Ostwald de Waele. The values of n and k vary from 0.31 to 0.64 and 0.19 to 0.81 Pa·sn,respectively. This paper presents an artificial neural network(ANN) model to predict the effects of operational parameters on apparent viscosity of CWS. A 4-2-1 topology with Levenberg-Marquardt training algorithm(trainlm) was selected as the controlled ANN. Mean squared error(MSE) of 0.002 and coefficient of multiple determinations(R^2) of 0.99 were obtained for the outperforming model. The promising values of correlation coefficient further confirm the robustness and satisfactory performance of the proposed ANN model. 展开更多
关键词 Microwave pre-treatment Coal-water slurry Apparent viscosity Artificial neural network Back propagation algorithm
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Performance prediction of gravity concentrator by using artificial neural network-a case study 被引量:3
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作者 Panda Lopamudra Tripathy Sunil Kumar 《International Journal of Mining Science and Technology》 SCIE EI 2014年第4期461-465,共5页
In conventional chromite beneficiation plant, huge quantity of chromite is used to loss in the form of tailing. For recovery these valuable mineral, a gravity concentrator viz. wet shaking table was used.Optimisation ... In conventional chromite beneficiation plant, huge quantity of chromite is used to loss in the form of tailing. For recovery these valuable mineral, a gravity concentrator viz. wet shaking table was used.Optimisation along with performance prediction of the unit operation is necessary for efficient recovery.So, in this present study, an artificial neural network(ANN) modeling approach was attempted for predicting the performance of wet shaking table in terms of grade(%) and recovery(%). A three layer feed forward neural network(3:3–11–2:2) was developed by varying the major operating parameters such as wash water flow rate(L/min), deck tilt angle(degree) and slurry feed rate(L/h). The predicted value obtained by the neural network model shows excellent agreement with the experimental values. 展开更多
关键词 Chromite Artificial neural network Wet shaking table Performance prediction Back propagation algorithm
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激光诱导击穿光谱结合RF-BPNN算法对裸鼠肺肿瘤分类的研究
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作者 彭颖婕 廉倩琳 +1 位作者 马越 陈建军 《科技通报》 2025年第3期21-28,共8页
肺癌是我国乃至全世界发病率和死亡率较高的恶性肿瘤之一,其早发现、早诊断、早治疗可以显著提高肺癌患者的预后,有效降低死亡率。本文采用激光诱导击穿光谱技术(laser-induced breakdown spectroscopy,LIBS)结合机器学习算法用于诊断... 肺癌是我国乃至全世界发病率和死亡率较高的恶性肿瘤之一,其早发现、早诊断、早治疗可以显著提高肺癌患者的预后,有效降低死亡率。本文采用激光诱导击穿光谱技术(laser-induced breakdown spectroscopy,LIBS)结合机器学习算法用于诊断和鉴别裸鼠肺肿瘤和肌肉组织。实验过程使用波长532 nm、能量40 mJ的激光器对200个裸鼠切片样本(100个肺肿瘤、100个肌肉组织)进行光谱差异性探究,并采用适合数据特征的机器学习算法,用于肺肿瘤和肌肉组织的分类诊断。通过样本的光谱波峰特征选取16条强元素谱线作为机器学习算法的特征向量,比较K-最近邻(k-nearest neighbor,KNN)、支持向量机(support vector machine,SVM)、反向传播神经网络(back propagation neural network,BPNN)算法的分类精度,并选出最优分类算法;然后基于变量重要性排序,采用随机森林(random forest,RF)算法,选取高于可变重要性平均值的变量作为最优分类算法新的特征向量。通过五折交叉验证,指标包括准确率、灵敏度、特异性、受试者工作ROC曲线(receiver operating curve)以及曲线下面积AUC值(area under curve)来对模型进行评价。结果表明:(1)对比LIBS光谱图发现肺肿瘤组织和正常肌肉组织光谱种类相似,均包含有金属元素、非金属元素和分子键的特征信息。(2)在KNN、SVM、BPNN 3种算法的比较中,BPNN模型为最优分类器,其准确率、灵敏度、特异性分别达到91.67%、97.1%、84.6%,AUC值为0.924。(3)RF重要性选择后的变量由16个减少到了7个,解决了高维数据特征冗余的问题。(4)将RF算法与BPNN分类器结合后,RF-BPNN的分类准确率、灵敏度、特异性分别提高到了96.7%、100%、94.1%,AUC值为0.964。 展开更多
关键词 肺肿瘤 激光诱导击穿光谱技术 机器学习 反向传播神经网络
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Underwater vehicle sonar self-noise prediction based on genetic algorithms and neural network
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作者 WU Xiao-guang SHI Zhong-kun 《Journal of Marine Science and Application》 2006年第2期36-41,共6页
The factors that influence underwater vehicle sonar self-noise are analyzed, and genetic algorithms and a back propagation (BP) neural network are combined to predict underwater vehicle sonar self-noise. The experimen... The factors that influence underwater vehicle sonar self-noise are analyzed, and genetic algorithms and a back propagation (BP) neural network are combined to predict underwater vehicle sonar self-noise. The experimental results demonstrate that underwater vehicle sonar self-noise can be predicted accurately by a GA-BP neural network that is based on actual underwater vehicle sonar data. 展开更多
关键词 sonar self-noise back propagation (BP) neural network genetic algorithms
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Neural Network Identification Model for Technology Selection of Fully-Mechanized Top-Coal Caving Mining
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作者 孟宪锐 徐永勇 汪进 《Journal of China University of Mining and Technology》 2001年第2期199-203,共5页
This paper mainly discusses the selection of the technical parameters of fully mechanized top coal caving mining using the neural network technique. The comparison between computing results and experiment data shows t... This paper mainly discusses the selection of the technical parameters of fully mechanized top coal caving mining using the neural network technique. The comparison between computing results and experiment data shows that the set up neural network model has high accuracy and decision making benefit. 展开更多
关键词 top coal caving mining artificial neural network reformative back propagation neural network
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O(t^(-β))-SYNCHRONIZATION AND ASYMPTOTIC SYNCHRONIZATION OF DELAYED FRACTIONAL ORDER NEURAL NETWORKS
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作者 Anbalagan PRATAP Ramachandran RAJA +3 位作者 Jinde CAO Chuangxia HUANG Jehad ALZABUT Ovidiu BAGDASAR 《Acta Mathematica Scientia》 SCIE CSCD 2022年第4期1273-1292,共20页
This article explores the O(t^(-β))synchronization and asymptotic synchronization for fractional order BAM neural networks(FBAMNNs)with discrete delays,distributed delays and non-identical perturbations.By designing ... This article explores the O(t^(-β))synchronization and asymptotic synchronization for fractional order BAM neural networks(FBAMNNs)with discrete delays,distributed delays and non-identical perturbations.By designing a state feedback control law and a new kind of fractional order Lyapunov functional,a new set of algebraic sufficient conditions are derived to guarantee the O(t^(-β))Synchronization and asymptotic synchronization of the considered FBAMNNs model;this can easily be evaluated without using a MATLAB LMI control toolbox.Finally,two numerical examples,along with the simulation results,illustrate the correctness and viability of the exhibited synchronization results. 展开更多
关键词 O(t^(-β))-synchronization asymptotic synchronization BAM neural networks fractional order state feedback control law
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基于KLDA-IDBO-BP的装甲车发动机故障诊断
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作者 李英顺 于昂 +2 位作者 李茂 贺喆 刘师铭 《兵工学报》 北大核心 2025年第3期105-113,共9页
润滑油在发动机中发挥作用时携带着大量关于发动机的状态信息,能够对发动机产生的故障进行表征,可利用其对发动机进行故障诊断。以某型装甲车辆发动机为研究对象,提出一种基于核线性判别和改进的蜣螂优化算法优化反向传播(Back Propagat... 润滑油在发动机中发挥作用时携带着大量关于发动机的状态信息,能够对发动机产生的故障进行表征,可利用其对发动机进行故障诊断。以某型装甲车辆发动机为研究对象,提出一种基于核线性判别和改进的蜣螂优化算法优化反向传播(Back Propagation,BP)神经网络的故障诊断方法。对获取的润滑油数据通过核线性判别分析进行降维处理,降维后的数据作为BP神经网络的输入,通过引入最优拉丁超立方、权重因子以及Levy飞行策略对蜣螂优化算法进行改进,进一步对BP神经网络的关键参数进行优化,建立故障诊断模型,实现对测试数据的故障预测。实验结果验证了新方法在进行故障诊断预测方面的有效性,为装甲车辆发动机的维护和修理提供了科学依据。 展开更多
关键词 润滑油信息 发动机 故障诊断 蜣螂优化算法 反向传播神经网络 核线性判别分析
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Combining the genetic algorithms with artificial neural networks for optimization of board allocating 被引量:2
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作者 曹军 张怡卓 岳琪 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第1期87-88,共2页
This paper introduced the Genetic Algorithms (GAs) and Artificial Neural Networks (ANNs), which have been widely used in optimization of allocating. The combination way of the two optimizing algorithms was used in boa... This paper introduced the Genetic Algorithms (GAs) and Artificial Neural Networks (ANNs), which have been widely used in optimization of allocating. The combination way of the two optimizing algorithms was used in board allocating of furniture production. In the experiment, the rectangular flake board of 3650 mm 1850 mm was used as raw material to allocate 100 sets of Table Bucked. The utilizing rate of the board reached 94.14 % and the calculating time was only 35 s. The experiment result proofed that the method by using the GA for optimizing the weights of the ANN can raise the utilizing rate of the board and can shorten the time of the design. At the same time, this method can simultaneously searched in many directions, thus greatly in-creasing the probability of finding a global optimum. 展开更多
关键词 Artificial neural network Genetic algorithms Back propagation model (BP model) OPTIMIZATION
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COMBINATION OF DISTRIBUTED KALMAN FILTER AND BP NEURAL NETWORK FOR ESG BIAS MODEL IDENTIFICATION 被引量:3
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作者 张克志 田蔚风 钱峰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第3期226-231,共6页
By combining the distributed Kalman filter (DKF) with the back propagation neural network (BPNN),a novel method is proposed to identify the bias of electrostatic suspended gyroscope (ESG). Firstly,the data sets ... By combining the distributed Kalman filter (DKF) with the back propagation neural network (BPNN),a novel method is proposed to identify the bias of electrostatic suspended gyroscope (ESG). Firstly,the data sets of multi-measurements of the same ESG in different noise environments are "mapped" into a sensor network,and DKF with embedded consensus filters is then used to preprocess the data sets. After transforming the preprocessed results into the trained input and the desired output of neural network,BPNN with the learning rate and the momentum term is further utilized to identify the ESG bias. As demonstrated in the experiment,the proposed approach is effective for the model identification of the ESG bias. 展开更多
关键词 model identification distributed Kalman filter(DKF) back propagation neural network(BPNN) electrostatic suspended gyroscope(ESG)
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VIRTUAL TARGET DIFFERENTIAL GAME MIDCOURSE GUIDANCE LAW FOR HYPERSONIC CRUISE MISSILE BASED ON NEURAL NETWORK 被引量:2
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作者 桑保华 姜长生 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第2期121-127,共7页
For the high altitude cruising flight phase of a hypersonic cruise missile (HCM), a relative motion mod- el between the missile and the target is established by defining virtual target and combining the theory of th... For the high altitude cruising flight phase of a hypersonic cruise missile (HCM), a relative motion mod- el between the missile and the target is established by defining virtual target and combining the theory of the dif- ferential geometry with missile motion equations. Based on the model, the motion between the missile and the tar- get is considered as a single target differential game problem, and a new open-loop differential game midcourse guidance law (DGMGL) is deduced by solving the corresponding Hamiltonian Function. Meanwhile, a new struc- ture of a closed-loop DGMGL is presented and the training data for back propagation neural network (BPNN) are designed. By combining the theory of BPNN with the open-loop DGMGL obtained above, the law intelligence is realized. Finally, simulation is carried out and the validity of the law is testified. 展开更多
关键词 missiles TARGETS GUIDES back propagation neural network differential game
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A REALIZATION OF FUZZY LOGIC BY A NEURAL NETWORK 被引量:1
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作者 杨忠 鲍明 赵淳生 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第1期104-108,共5页
This paper proposes a Fuzzy Neural Network (FNN) model, which uses a propagation algorithm. A logical operation is defined by a set of weights which are independent of inputs. The realization of the basic And,Or and N... This paper proposes a Fuzzy Neural Network (FNN) model, which uses a propagation algorithm. A logical operation is defined by a set of weights which are independent of inputs. The realization of the basic And,Or and Negation fuzzy logical operations is shown by the fuzzy neuron. A example in fault diagnosis is put forward and the result witnesses some effectiveness of the new FNN model. 展开更多
关键词 fuzzy logic NEURON neural network propagation algorithm fault diagnosis
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基于PSO-LSSVM-BP模型的高边坡力学参数反分析及稳定性评价 被引量:2
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作者 徐卫亚 陈世壮 +5 位作者 张贵科 胡明涛 黄威 许晓逸 张海龙 王如宾 《河海大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第5期52-59,共8页
基于粒子群优化(PSO)算法和最小二乘支持向量机(LSSVM)算法构建非线性映射关系,结合反向传播(BP)神经网络对非线性映射关系生成的数据库进行机器学习,构建了PSO-LSSVM-BP模型确定最优岩体力学参数。PSO-LSSVM-BP模型以高边坡监测位移数... 基于粒子群优化(PSO)算法和最小二乘支持向量机(LSSVM)算法构建非线性映射关系,结合反向传播(BP)神经网络对非线性映射关系生成的数据库进行机器学习,构建了PSO-LSSVM-BP模型确定最优岩体力学参数。PSO-LSSVM-BP模型以高边坡监测位移数据作为输入信息,通过反分析获得高边坡岩体力学参数,将反分析参数用于FLAC3D位移数值计算,结果表明模拟结果与监测数据吻合较好,验证了该模型的可行性和有效性。基于PSO-LSSVM-BP模型,对不同蓄水位下两河口水电站进水口高边坡稳定性进行了评价,发现水位是影响边坡稳定性的主要因素,随着水位上升,边坡位移逐渐增大,其表面和断层处损伤程度加深,边坡局部点安全系数有所下降,但整体点安全系数均大于1.30,有一定安全裕度。 展开更多
关键词 高边坡 力学参数反分析 粒子群优化 最小二乘向量机 反向传播神经网络 两河口水电站
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基于PIWT-IPSO-BP的污水厂出水COD含量的预测模型 被引量:1
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作者 张净 窦慧芸 +1 位作者 蒋武 刘晓梅 《中国农村水利水电》 北大核心 2024年第9期15-20,28,共7页
在农业灌溉的领域中,化学需氧量(Chemical Oxygen Demand,COD)的测定是衡量水体中有机物污染程度的一个重要指标。当COD浓度超过60mg/L时,其对土壤质量和农作物的生长产生的负面影响成为不容忽视的问题。这一现象可能会严重影响农作物... 在农业灌溉的领域中,化学需氧量(Chemical Oxygen Demand,COD)的测定是衡量水体中有机物污染程度的一个重要指标。当COD浓度超过60mg/L时,其对土壤质量和农作物的生长产生的负面影响成为不容忽视的问题。这一现象可能会严重影响农作物的产量和质量,进而对农作物生产的可持续性构成挑战。因此,有必要精确预测污水处理厂出水COD浓度的变化趋势,从而促进其在农业灌溉中的有效应用。研究结合了改进的小波变换、改进的粒子群优化(Improved Particle Swarm Optimization,IPSO)算法和反向传播BP(Back Propagation,BP)神经网络作为预测模型。鉴于COD受到众多因素的影响,这些因素之间存在复杂的耦合关系,采用PCA进行特征提取。考虑到数据采集的过程中不可避免的噪声干扰,应用小波降噪对原始数据进行处理,以确保数据质量,提高模型准确性。在此基础上,基于BP神经网络算法构建污水处理厂出水COD的预测模型。为了解决BP神经网络参数选择可能遇到的盲目性问题,引入改进的粒子群算法对模型进行参数优化,以提高预测精度。实验结果表明,提出的PIWT-IPSO-BP模型预测效果良好,其平均绝对误差、均方根误差和决定系数分别为0.222、0.386和0.984。该模型在一定程度上改善了数据噪声、多因子制约等问题,为污水循环利用技术应用于农业灌溉方面提供了参考依据。 展开更多
关键词 化学需氧量 预测模型 小波变换 粒子群优化算法 BP神经网络
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采用遗传-反向传播人工神经网络法构建新疆地区癫痫患儿拉考沙胺血药浓度预测模型
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作者 赵婷 孙岩 +5 位作者 李红健 张惠兰 于静 冯杰 王婷婷 于鲁海 《儿科药学杂志》 CAS 2024年第4期4-8,共5页
目的:利用遗传-反向传播(GA-BP)人工神经网络法构建新疆地区癫痫患儿拉考沙胺(LCM)血药浓度的预测模型。方法:采用超高效液相色谱法测定400例癫痫患儿的LCM稳态血药浓度,收集患儿临床资料,提取相关数据,采用GA-BP人工神经网络法构建LCM... 目的:利用遗传-反向传播(GA-BP)人工神经网络法构建新疆地区癫痫患儿拉考沙胺(LCM)血药浓度的预测模型。方法:采用超高效液相色谱法测定400例癫痫患儿的LCM稳态血药浓度,收集患儿临床资料,提取相关数据,采用GA-BP人工神经网络法构建LCM血药浓度的预测模型。结果:模型验证结果显示,80例预测浓度的平均预测误差(MPE)绝对值均<10%,预测误差(PE)绝对值<20%的比例是100%,PE绝对值<10%的比例是92.50%,平均预测绝对误差(MAE)为2.28%,提示GA-BP模型预测的准确度和精密度均较好,预测浓度和实测浓度的相关系数为0.998,预测结果较理想。结论:应用GA-BP人工神经网络法预测LCM血药浓度是可行的,可应用于LCM个体化给药研究,促进临床合理用药。 展开更多
关键词 癫痫 拉考沙胺 血药浓度 遗传-反向传播人工神经网络
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基于测点聚类的POD-BPNN风压重构方法
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作者 杜晓庆 沈祥宇 +1 位作者 董浩天 陈统岳 《土木工程学报》 EI CSCD 北大核心 2024年第9期11-21,共11页
文章提出本征正交分解(POD)与聚类分析结合的结构表面风压测点分类与关键测点布置方法,基于少量测点的风压数据,通过POD与误差反向传播神经网络(BPNN)方法实现方柱结构表面风压时程的重构。机器学习数据集为多风向角均匀来流下单方柱测... 文章提出本征正交分解(POD)与聚类分析结合的结构表面风压测点分类与关键测点布置方法,基于少量测点的风压数据,通过POD与误差反向传播神经网络(BPNN)方法实现方柱结构表面风压时程的重构。机器学习数据集为多风向角均匀来流下单方柱测压风洞试验得到的测点风压时程。将44个测点的风压时程数据POD降维,并采用K-means++聚类分析得到方柱周向轮廓系数分布,并基于轮廓系数的多风向角平均值,得到12、16、20和24个关键测点的轴对称布置方案。以关键测点的风压时程数据为训练集,采用POD-BPNN方法重构方柱表面其余测点所在位置的风压时程,并将风压时程及其统计值同试验结果对比。从12~20测点方案,风压重构精度逐步提升;20测点和24测点方案的重构风压差异较小,二者都能较好地重构方柱表面风压分布,仅在0°风向角方柱脉动风压误差偏大。 展开更多
关键词 风压时程重构 聚类分析 本征正交分解 误差反向传播神经网络 风压测点布置
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