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Shallow water bathymetry based on a back propagation neural network and ensemble learning using multispectral satellite imagery
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作者 Sensen Chu Liang Cheng +4 位作者 Jian Cheng Xuedong Zhang Jie Zhang Jiabing Chen Jinming Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第5期154-165,共12页
The back propagation(BP)neural network method is widely used in bathymetry based on multispectral satellite imagery.However,the classical BP neural network method faces a potential problem because it easily falls into... The back propagation(BP)neural network method is widely used in bathymetry based on multispectral satellite imagery.However,the classical BP neural network method faces a potential problem because it easily falls into a local minimum,leading to model training failure.This study confirmed that the local minimum problem of the BP neural network method exists in the bathymetry field and cannot be ignored.Furthermore,to solve the local minimum problem of the BP neural network method,a bathymetry method based on a BP neural network and ensemble learning(BPEL)is proposed.First,the remote sensing imagery and training sample were used as input datasets,and the BP method was used as the base learner to produce multiple water depth inversion results.Then,a new ensemble strategy,namely the minimum outlying degree method,was proposed and used to integrate the water depth inversion results.Finally,an ensemble bathymetric map was acquired.Anda Reef,northeastern Jiuzhang Atoll,and Pingtan coastal zone were selected as test cases to validate the proposed method.Compared with the BP neural network method,the root-mean-square error and the average relative error of the BPEL method can reduce by 0.65–2.84 m and 16%–46%in the three test cases at most.The results showed that the proposed BPEL method could solve the local minimum problem of the BP neural network method and obtain highly robust and accurate bathymetric maps. 展开更多
关键词 BATHYMETRY back propagation neural network ensemble learning local minimum problem multispectral satellite imagery
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Prediction of SMILE surgical cutting formula based on back propagation neural network
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作者 Dong-Qing Yuan Fu-Nan Tang +5 位作者 Chun-Hua Yang Hui Zhang Ying Wang Wei-Wei Zhang Liu-Wei Gu Qing-Huai Liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第9期1424-1430,共7页
AIM:To predict cutting formula of small incision lenticule extraction(SMILE)surgery and assist clinicians in identifying candidates by deep learning of back propagation(BP)neural network.METHODS:A prediction program w... AIM:To predict cutting formula of small incision lenticule extraction(SMILE)surgery and assist clinicians in identifying candidates by deep learning of back propagation(BP)neural network.METHODS:A prediction program was developed by a BP neural network.There were 13188 pieces of data selected as training validation.Another 840 eye samples from 425 patients were recruited for reverse verification of training results.Precision of prediction by BP neural network and lenticule thickness error between machine learning and the actual lenticule thickness in the patient data were measured.RESULTS:After training 2313 epochs,the predictive SMILE cutting formula BP neural network models performed best.The values of mean squared error and gradient are 0.248 and 4.23,respectively.The scatterplot with linear regression analysis showed that the regression coefficient in all samples is 0.99994.The final error accuracy of the BP neural network is-0.003791±0.4221102μm.CONCLUSION:With the help of the BP neural network,the program can calculate the lenticule thickness and residual stromal thickness of SMILE surgery accurately.Combined with corneal parameters and refraction of patients,the program can intelligently and conveniently integrate medical information to identify candidates for SMILE surgery. 展开更多
关键词 small incision lenticule extraction back propagation neural network deep learning cutting formula PREDICTION
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Novel Contiguous Cross Propagation Neural Network Built CAD for Lung Cancer
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作者 A.Alice Blessie P.Ramesh 《Computer Systems Science & Engineering》 SCIE EI 2023年第2期1467-1484,共18页
The present progress of visual-based detection of the diseased area of a malady plays an essential part in the medicalfield.In that case,the image proces-sing is performed to improve the image data,wherein it inhibits ... The present progress of visual-based detection of the diseased area of a malady plays an essential part in the medicalfield.In that case,the image proces-sing is performed to improve the image data,wherein it inhibits unintended dis-tortion of image features or it enhances further processing in various applications andfields.This helps to show better results especially for diagnosing diseases.Of late the early prediction of cancer is necessary to prevent disease-causing pro-blems.This work is proposed to identify lung cancer using lung computed tomo-graphy(CT)scan images.It helps to identify cancer cells’affected areas.In the present work,the original input image from Lung Image Database Consortium(LIDC)typically suffers from noise problems.To overcome this,the Gaborfilter used for image processing is highly enhanced.In the next stage,the Spherical Iterative Refinement Clustering(SIRC)algorithm identifies cancer-suspected areas on the CT scan image.This approach can help radiologists and medical experts recognize cancer diseases and syndromes so that serious progress can be avoided in the early stages.These new methods help to remove unwanted por-tions of the CT image and better utilization the image.The subspace extraction of features approach is beneficial for evaluating lung cancer.This paper introduces a novel approach called Contiguous Cross Propagation Neural Network that tends to locate regions afflicted by lung cancer using CT scan pictures(CCPNN).By using the feature values from the fourth step of the procedure,the proposed CCPNN tends to categorize the lesion in the lung nodular site.The efficiency of the suggested CCPNN approach is evaluated using classification metrics such as recall(%),precision(%),F-measure(percent),and accuracy(%).Finally,the incorrect classification ratios are determined to compare the trained networks’effectiveness,through these parameters of CCPNN,it obtains the outstanding per-formance of 98.06%and it has provided the lowest false ratio of 1.8%. 展开更多
关键词 Contiguous cross propagation neural network(CCPNN) Gaborfilter
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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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A sub-grid scale model for Burgers turbulence based on the artificial neural network method
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作者 Xin Zhao Kaiyi Yin 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第3期162-165,共4页
The present study proposes a sub-grid scale model for the one-dimensional Burgers turbulence based on the neuralnetwork and deep learning method.The filtered data of the direct numerical simulation is used to establis... The present study proposes a sub-grid scale model for the one-dimensional Burgers turbulence based on the neuralnetwork and deep learning method.The filtered data of the direct numerical simulation is used to establish thetraining data set,the validation data set,and the test data set.The artificial neural network(ANN)methodand Back Propagation method are employed to train parameters in the ANN.The developed ANN is applied toconstruct the sub-grid scale model for the large eddy simulation of the Burgers turbulence in the one-dimensionalspace.The proposed model well predicts the time correlation and the space correlation of the Burgers turbulence. 展开更多
关键词 Artificial neural network Back propagation method Burgers turbulence Large eddy simulation Sub-grid scale model
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FORCE RIPPLE SUPPRESSION TECHNOLOGY FOR LINEAR MOTORS BASED ON BACK PROPAGATION NEURAL NETWORK 被引量:7
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作者 ZHANG Dailin CHEN Youping +2 位作者 AI Wu ZHOU Zude KONG Ching Tom 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第2期13-16,共4页
Various force disturbances influence the thrust force of linear motors when a linear motor (LM) is running. Among all of force disturbances, the force ripple is the dominant while a linear motor runs in low speed. I... Various force disturbances influence the thrust force of linear motors when a linear motor (LM) is running. Among all of force disturbances, the force ripple is the dominant while a linear motor runs in low speed. In order to suppress the force ripple, back propagation(BP) neural network is proposed to learn the function of the force ripple of linear motors, and the acquisition method of training samples is proposed based on a disturbance observer. An off-line BP neural network is used mainly because of its high running efficiency and the real-time requirement of the servo control system of a linear motor. By using the function, the force ripple is on-line compensated according to the position of the LM. The experimental results show that the force ripple is effectively suppressed by the compensation of the BP neural network. 展开更多
关键词 Linear motor (LM) Back propagation(BP) algorithm neural network Anti-disturbance technology
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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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Application of the back-error propagation artificial neural network(BPANN) on genetic variants in the PPAR-γ and RXR-α gene and risk of metabolic syndrome in a Chinese Han population 被引量:3
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作者 Xu Zhao Kang Xu +11 位作者 Hui Shi Jinluo Cheng Jianhua Ma Yanqin Gao Qian Li Xinhua Ye Ying Lu Xiaofang Yu Juan Du Wencong Du Qing Ye Ling Zhou 《The Journal of Biomedical Research》 CAS 2014年第2期114-122,共9页
This study was aimed to explore the associations between the combined effects of several polymorphisms in the PPAR-γ and RXR-α gene and environmental factors with the risk of metabolic syndrome by back-error propaga... This study was aimed to explore the associations between the combined effects of several polymorphisms in the PPAR-γ and RXR-α gene and environmental factors with the risk of metabolic syndrome by back-error propaga- tion artificial neural network (BPANN). We established the model based on data gathered from metabolic syndrome patients (n = 1012) and normal controls (n = 1069) by BPANN. Mean impact value (MIV) for each input variable was calculated and the sequence of factors was sorted according to their absolute MIVs. Generalized multifactor dimensionality reduction (GMDR) confirmed a joint effect of PPAR-9" and RXR-a based on the results from BPANN. By BPANN analysis, the sequences according to the importance of metabolic syndrome risk fac- tors were in the order of body mass index (BMI), serum adiponectin, rs4240711, gender, rs4842194, family history of type 2 diabetes, rs2920502, physical activity, alcohol drinking, rs3856806, family history of hypertension, rs1045570, rs6537944, age, rs17817276, family history of hyperlipidemia, smoking, rs1801282 and rs3132291. However, no polymorphism was statistically significant in multiple logistic regression analysis. After controlling for environmental factors, A1, A2, B1 and B2 (rs4240711, rs4842194, rs2920502 and rs3856806) models were the best models (cross-validation consistency 10/10, P = 0.0107) with the GMDR method. In conclusion, the interaction of the PPAR-γ and RXR-α gene could play a role in susceptibility to metabolic syndrome. A more realistic model is obtained by using BPANN to screen out determinants of diseases of multiple etiologies like metabolic syndrome. 展开更多
关键词 back-error propagation artificial neural network (BPANN) metabolic syndrome peroxisome prolif-erators activated receptor-γ (PPAR) gene retinoid X receptor-α (RXR-α) gene ADIPONECTIN
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Fashion Color Forecasting by Applying an Improved Back Propagation Neural Network 被引量:2
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作者 常丽霞 潘如如 高卫东 《Journal of Donghua University(English Edition)》 EI CAS 2013年第1期58-62,共5页
Fashion color forecasting is one of the most important factors for fashion marketing and manufacturing. Several models have been applied by previous researchers to conduct fashion color forecasting. However, few convi... Fashion color forecasting is one of the most important factors for fashion marketing and manufacturing. Several models have been applied by previous researchers to conduct fashion color forecasting. However, few convincing forecasting systems have been established. A prediction model for fashion color forecasting was established by applying an improved back propagation neural network (BPNN) model in this paper. Successive six-year fashion color palettes, released by INTERCOLOR, were used as learning information for the neural network to develop a reliable prediction model. Colors in the palettes were quantified by PANTONE color system. Additionally, performance of the established model was compared with other GM(1, 1) models. Results show that the improved BPNN model is suitable to predict future fashion color trend. 展开更多
关键词 fashion color back propagation neural network(BPNN) trend forecasting momentum factor
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A Method for Solving Computer-Aided Product Design Optimization Problem Based on Back Propagation Neural Network 被引量:1
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作者 周祥 何小荣 陈丙珍 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第4期510-514,共5页
Because of the powerful mapping ability, back propagation neural network (BP-NN) has been employed in computer-aided product design (CAPD) to establish the property prediction model. The backward problem in CAPD is to... Because of the powerful mapping ability, back propagation neural network (BP-NN) has been employed in computer-aided product design (CAPD) to establish the property prediction model. The backward problem in CAPD is to search for the appropriate structure or composition of the product with desired property, which is an optimization problem. In this paper, a global optimization method of using the a BB algorithm to solve the backward problem is presented. In particular, a convex lower bounding function is constructed for the objective function formulated with BP-NN model, and the calculation of the key parameter a is implemented by recurring to the interval Hessian matrix of the objective function. Two case studies involving the design of dopamine β-hydroxylase (DβH) inhibitors and linear low density polyethylene (LLDPE) nano composites are investigated using the proposed method. 展开更多
关键词 computer-aided product design (CAPD) back propagation neural network (bp-nn) a BB algorithm convex lower bounding function interval Hessian matrix
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Surface Quality Evaluation of Fluff Fabric Based on Particle Swarm Optimization Back Propagation Neural Network 被引量:1
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作者 MA Qiurui LIN Qiangqiang JIN Shoufeng 《Journal of Donghua University(English Edition)》 EI CAS 2019年第6期539-546,共8页
Aiming at the problem that back propagation(BP)neural network predicts the low accuracy rate of fluff fabric after fluffing process,a BP neural network model optimized by particle swarm optimization(PSO)algorithm is p... Aiming at the problem that back propagation(BP)neural network predicts the low accuracy rate of fluff fabric after fluffing process,a BP neural network model optimized by particle swarm optimization(PSO)algorithm is proposed.The sliced image is obtained by the principle of light-cutting imaging.The fluffy region of the adaptive image segmentation is extracted by the Freeman chain code principle.The upper edge coordinate information of the fabric is subjected to one-dimensional discrete wavelet decomposition to obtain high frequency information and low frequency information.After comparison and analysis,the BP neural network was trained by high frequency information,and the PSO algorithm was used to optimize the BP neural network.The optimized BP neural network has better weights and thresholds.The experimental results show that the accuracy of the optimized BP neural network after applying high-frequency information training is 97.96%,which is 3.79%higher than that of the unoptimized BP neural network,and has higher detection accuracy. 展开更多
关键词 WOOL FABRIC feature extraction WAVELET TRANSFORM particle SWARM optimization(PSO) back propagation(BP)neural network
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A Review on Back-Propagation Neural Networks in the Application of Remote Sensing Image Classification 被引量:2
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作者 Alaeldin Suliman Yun Zhang 《Journal of Earth Science and Engineering》 2015年第1期52-65,共14页
ANNs (Artificial neural networks) are used extensively in remote sensing image processing. It has been proven that BPNNs (back-propagation neural networks) have high attainable classification accuracy. However, th... ANNs (Artificial neural networks) are used extensively in remote sensing image processing. It has been proven that BPNNs (back-propagation neural networks) have high attainable classification accuracy. However, there is a noticeable variation in the achieved accuracies due to different network designs and implementations. Hence, researchers usually need to conduct several experimental trials before they can finalize the network design. This is a time consuming process which significantly reduces the effectiveness of using BPNNs and the final design may still not be optimal. Therefore, there is a need to see whether there are some common guidelines for effective design and implementation of BPNNs. With this aim in mind, this paper attempts to find and summarize the common guidelines suggested by different authors through literature review and discussion of the findings. To provide readers with background and contextual information, some ANN fundamentals are also introduced. 展开更多
关键词 Artificial neural networks back propagation CLASSIFICATION remote sensing.
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Pseudo Random Number Generator Based on Back Propagation Neural Network 被引量:3
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作者 WANG Bang-ju WANG Yu-hua +1 位作者 NIU Li-ping ZHANG Huan-guo 《Semiconductor Photonics and Technology》 CAS 2007年第2期164-168,共5页
Random numbers play an increasingly important role in secure wire and wireless communication. Thus the design quality of random number generator(RNG) is significant in information security. A novel pseudo RNG is propo... Random numbers play an increasingly important role in secure wire and wireless communication. Thus the design quality of random number generator(RNG) is significant in information security. A novel pseudo RNG is proposed for improving the security of network communication. The back propagation neural network(BPNN) is nonlinear, which can be used to improve the traditional RNG. The novel pseudo RNG is based on BPNN techniques. The result of test suites standardized by the U.S shows that the RNG can satisfy the security of communication. 展开更多
关键词 pseudo random number generator(PRNN) random number generator(RNG) back propagation neural network(BPNN)
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Combinatorial Optimization Based Analog Circuit Fault Diagnosis with Back Propagation Neural Network 被引量:1
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作者 李飞 何佩 +3 位作者 王向涛 郑亚飞 郭阳明 姬昕禹 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期774-778,共5页
Electronic components' reliability has become the key of the complex system mission execution. Analog circuit is an important part of electronic components. Its fault diagnosis is far more challenging than that of... Electronic components' reliability has become the key of the complex system mission execution. Analog circuit is an important part of electronic components. Its fault diagnosis is far more challenging than that of digital circuit. Simulations and applications have shown that the methods based on BP neural network are effective in analog circuit fault diagnosis. Aiming at the tolerance of analog circuit,a combinatorial optimization diagnosis scheme was proposed with back propagation( BP) neural network( BPNN).The main contributions of this scheme included two parts:( 1) the random tolerance samples were added into the nominal training samples to establish new training samples,which were used to train the BP neural network based diagnosis model;( 2) the initial weights of the BP neural network were optimized by genetic algorithm( GA) to avoid local minima,and the BP neural network was tuned with Levenberg-Marquardt algorithm( LMA) in the local solution space to look for the optimum solution or approximate optimal solutions. The experimental results show preliminarily that the scheme substantially improves the whole learning process approximation and generalization ability,and effectively promotes analog circuit fault diagnosis performance based on BPNN. 展开更多
关键词 analog circuit fault diagnosis back propagation(BP) neural network combinatorial optimization TOLERANCE genetic algorithm(G A) Levenberg-Marquardt algorithm(LMA)
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The Prediction of Propagation Loss of FM Radio Station Using Artificial Neural Network 被引量:1
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作者 Ali Riza Ozdemir Mustafa Alkan +2 位作者 Mehmet Kabak Mehmet Gulsen Murat Hüsnü Sazli 《Journal of Electromagnetic Analysis and Applications》 2014年第11期358-365,共8页
In order to calculate the propagation loss of electromagnetic waves produced by a transmitter, a variety of models based on empirical and deterministic formulas are used. In this study, one of the artificial neural ne... In order to calculate the propagation loss of electromagnetic waves produced by a transmitter, a variety of models based on empirical and deterministic formulas are used. In this study, one of the artificial neural networks models, Levenberg-Marquardt algorithm, which is quite effective for predicting the propagation is used and the results obtained by this algorithm are compared with the simulation results based on ITU-R 1546 and Epstein-Peterson models. In this paper, the propagation loss of FM radio station using artificial neural networks models is studied depending on the Levenberg-Marquardt algorithm. For training the artificial neural network, as the input data;range (r), effective antenna height (h) and terrain irregularity (△H) parameters are involved and measured values are treated as the output data. The good results obtained in the city area reveal that the artificial neural network is a very efficient method to compute models which integrate theoretical and experimental data. Meanwhile, the results show that an ANN model performs very well compared with theoretical and empiric propagation models with regard to prediction accuracy, complexity, and prediction time. By comparing the results, the RMSE for Neural Network Model using Levenberg-Marquardt is 9.57, and it is lower than that of classical propagation model using Epstein-Peterson for which RMSE is 10.26. 展开更多
关键词 Artificial neural network PREDICTION of propagation
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Projected change in precipitation forms in the Chinese Tianshan Mountains based on the Back Propagation Neural Network Model 被引量:1
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作者 REN Rui LI Xue-mei +2 位作者 LI Zhen LI Lan-hai HUANG Yi-yu 《Journal of Mountain Science》 SCIE CSCD 2022年第3期689-703,共15页
In the context of global warming,precipitation forms are likely to transform from snowfall to rainfall with a more pronounced trend.The change in precipitation forms will inevitably affect the processes of regional ru... In the context of global warming,precipitation forms are likely to transform from snowfall to rainfall with a more pronounced trend.The change in precipitation forms will inevitably affect the processes of regional runoff generation and confluence as well as the annual distribution of runoff.Most researchers used precipitation data from the CMIP5 model directly to study future precipitation trends without distinguishing between snowfall and rainfall.CMIP5 models have been proven to have better performance in simulating temperature but poorer performance in simulating precipitation.To overcome the above limitations,this paper used a Back Propagation Neural Network(BNN)to predict the rainfall-to-precipitation ratio(RPR)in months experiencing freezing-thawing transitions(FTTs).We utilized the meteorological(air pressure,air temperature,evaporation,relative humidity,wind speed,sunshine hours,surface temperature),topographic(altitude,slope,aspect)and geographic(longitude,latitude)data from 28 meteorological stations in the Chinese Tianshan Mountains region(CTMR)from 1961 to 2018 to calculate the RPR and constructed an index system of impact factors.Based on the BNN,decision-making trial and evaluation laboratory method(BP-DEMATEL),the key factors driving the transformation of the RPR in the CTMR were identified.We found that temperature was the only key factor affecting the transformation of the RPR in the BP-DEMATEL model.Considering the relationship between temperature and the RPR,the future temperature under different representative concentration pathways(RCPs)(RCP2.6/RCP4.5/RCP8.5)provided by 21 CMIP5 models and the meteorological factors from meteorological stations were input into the BNN model to acquire the future RPR from 2011 to 2100.The results showed that under the three scenarios,the RPR in the number of months experiencing FTTs during 2011-2100 will be higher than that in the historical period(1981-2010)in the CTMR.Furthermore,in terms of spatial variation,the RPR values on the south slope will be larger than those on the north slope under the three emission scenarios.Moreover,the RPR values exhibited different variation characteristics under different emission scenarios.Under the low-emission scenario(RCP2.6),as time passed,the RPR values changed slightly at more stations.Under the mediumemission scenario(RCP4.5),the RPR increased in the whole CTMR and stabilized on the north slope by the end of this century.Under the high-emission scenario(RCP8.5),the RPR values increased significantly through the 21 st century in the whole CTMR.This study may help to provide a scientific management basis for agricultural production and hydrology. 展开更多
关键词 Global warming Tianshan Mountains region Precipitation forms CMIP5 models Back propagation neural network Model
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DAMAGE DETECTION IN STRUCTURES USING MODIFIED BACK-PROPAGATION NEURAL NETWORKS 被引量:6
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作者 Sima Yuzhou 《Acta Mechanica Solida Sinica》 SCIE EI 2002年第4期358-370,共13页
A nonparametric structural damage detection methodology based on neuralnetworks method is presented for health monitoring of structure-unknown systems. In this approachappropriate neural networks are trained by use of... A nonparametric structural damage detection methodology based on neuralnetworks method is presented for health monitoring of structure-unknown systems. In this approachappropriate neural networks are trained by use of the modal test data from a 'healthy' structure.The trained networks which are subsequently fed with vibration measurements from the same structurein different stages have the capability of recognizing the location and the content of structuraldamage and thereby can monitor the health of the structure. A modified back-propagation neuralnetwork is proposed to solve the two practical problems encountered by the traditionalback-propagation method, i.e., slow learning progress and convergence to a false local minimum.Various training algorithms, types of the input layer and numbers of the nodes in the input layerare considered. Numerical example results from a 5-degree-of-freedom spring-mass structure andanalyses on the experimental data of an actual 5-storey-steel-frame demonstrate thatneural-networks-based method is a robust procedure and a practical tool for the detection ofstructural damage, and that the modified back-propagation algorithm could improve the computationalefficiency as well as the accuracy of detection. 展开更多
关键词 neural network modified back-propagation damage detection modal testdata health monitoring
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Gear Fault Detection Analysis Method Based on Fractional Wavelet Transform and Back Propagation Neural Network 被引量:1
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作者 Yanqiang Sun Hongfang Chen +1 位作者 Liang Tang Shuang Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第12期1011-1028,共18页
A gear fault detection analysis method based on Fractional Wavelet Transform(FRWT)and Back Propagation Neural Network(BPNN)is proposed.Taking the changing order as the variable,the optimal order of gear vibration sign... A gear fault detection analysis method based on Fractional Wavelet Transform(FRWT)and Back Propagation Neural Network(BPNN)is proposed.Taking the changing order as the variable,the optimal order of gear vibration signals is determined by discrete fractional Fourier transform.Under the optimal order,the fractional wavelet transform is applied to eliminate noise from gear vibration signals.In this way,useful components of vibration signals can be successfully separated from background noise.Then,a set of feature vectors obtained by calculating the characteristic parameters for the de-noised signals are used to characterize the gear vibration features.Finally,the feature vectors are divided into two groups,including training samples and testing samples,which are input into the BPNN for learning and classification.Experimental results showed that this gear fault detection analysis method could well maintain the useful signal components related to gear faults and effectively extract the weak fault feature.The accuracy rate reached 96.67%in the identification of the type of gear fault. 展开更多
关键词 Gear fault detection preparation factional wavelet transform back propagation neural network
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Sound Quality Prediction of Vehicle Interior Noise under Multiple Working Conditions Using Back-Propagation Neural Network Model 被引量:1
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作者 Zutong Duan Yansong Wang Yanfeng Xing 《Journal of Transportation Technologies》 2015年第2期134-139,共6页
This paper presents a back-propagation neural network model for sound quality prediction (BPNN-SQP) of multiple working conditions’ vehicle interior noise. According to the standards and regulations, four kinds of ve... This paper presents a back-propagation neural network model for sound quality prediction (BPNN-SQP) of multiple working conditions’ vehicle interior noise. According to the standards and regulations, four kinds of vehicle interior noises under operating conditions, including idle, constant speed, accelerating and braking, are acquired. The objective psychoacoustic parameters and subjective annoyance results are respectively used as the input and output of the BPNN-SQP model. With correlation analysis and significance test, some psychoacoustic parameters, such as loudness, A-weighted sound pressure level, roughness, articulation index and sharpness, are selected for modeling. The annoyance values of unknown noise samples estimated by the BPNN-SQP model are highly correlated with the subjective annoyances. Conclusion can be drawn that the proposed BPNN-SQP model has good generalization ability and can be applied in sound quality prediction of vehicle interior noise under multiple working conditions. 展开更多
关键词 Multiple Working Conditions neural network BACK-propagation SOUND Quality PREDICTION ANNOYANCE
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Preparation of ZrB_2-SiC Powders via Carbothermal Reduction of Zircon and Prediction of Product Composition by Back-Propagation Artificial Neural Network 被引量:1
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作者 LIU Jianghao DU Shuang +2 位作者 LI Faliang ZHANG Haijun ZHANG Shaoweia 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第5期1062-1069,共8页
Phase pure ZrB2-SiC composite powders were prepared after 1 450℃/3 h via carbothermal reduction route,by using ZrSiO4,B2O3 and carbon as the raw materials.The influences of firing temperature as well as the type and ... Phase pure ZrB2-SiC composite powders were prepared after 1 450℃/3 h via carbothermal reduction route,by using ZrSiO4,B2O3 and carbon as the raw materials.The influences of firing temperature as well as the type and amount of additive on the phase composition of final products were detailedly investigated.The results indicated that the onset formation temperature of ZrB2-SiC was reduced to 1 400℃by the present conditions,and oxide additive(including CoSO4·7H2O,Y2O3 and TiO2)was effective in enhancing the decomposition of raw ZrSiO4,therefore accelerating the synthesis of ZrB2-SiC.Moreover,microstructural observation showed that the as-prepared ZrB2 and SiC respectively had well-defined hexagonal columnar and fibrous morphology.Furthermore,the methodology of back-propagation artificial neural networks(BP-ANNs)was adopted to establish a model for predicting the reaction extent(e g,the content of ZrB2-SiC in final product)in terms of various processing conditions.The results predicted by the as-established BP-ANNs model matched well with that of testing experiment(with a mean square error in 10^(-3) degree),verifying good effectiveness of the proposed strategy. 展开更多
关键词 ZrB2-SiC powders carbothermal reduction back-propagation artificial neural networks (BP-ANNs) composition prediction
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