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Application of wavelet neural network in the acoustic logging-while-drilling waveform data processing
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作者 ZHANG Wei SHI Yi-bing 《通讯和计算机(中英文版)》 2007年第8期29-34,共6页
关键词 小波神经网络 数据压缩 随钻声波测井技术 波形数据 油田
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APPLICATION OF NOISE REDUCTION METHOD BASED ON CURVELET THRESHOLDING NEURAL NETWORK FOR POLAR ICE RADAR DATA PROCESSING 被引量:1
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作者 Wang Wenpeng Zhao Bo Liu Xiaojun 《Journal of Electronics(China)》 2013年第4期377-383,共7页
Due to the demand of data processing for polar ice radar in our laboratory, a Curvelet Thresholding Neural Network (TNN) noise reduction method is proposed, and a new threshold function with infinite-order continuous ... Due to the demand of data processing for polar ice radar in our laboratory, a Curvelet Thresholding Neural Network (TNN) noise reduction method is proposed, and a new threshold function with infinite-order continuous derivative is constructed. The method is based on TNN model. In the learning process of TNN, the gradient descent method is adopted to solve the adaptive optimal thresholds of different scales and directions in Curvelet domain, and to achieve an optimal mean square error performance. In this paper, the specific implementation steps are presented, and the superiority of this method is verified by simulation. Finally, the proposed method is used to process the ice radar data obtained during the 28th Chinese National Antarctic Research Expedition in the region of Zhongshan Station, Antarctica. Experimental results show that the proposed method can reduce the noise effectively, while preserving the edge of the ice layers. 展开更多
关键词 Radar data processing Thresholding neural network (TNN) CURVELET Ice radar
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Predicting formation lithology from log data by using a neural network 被引量:6
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作者 Wang Kexiong Zhang Laibin 《Petroleum Science》 SCIE CAS CSCD 2008年第3期242-246,共5页
In order to increase drilling speed in deep complicated formations in Kela-2 gas field, Tarim Basin, Xinjiang, west China, it is important to predict the formation lithology for drilling bit optimization. Based on the... In order to increase drilling speed in deep complicated formations in Kela-2 gas field, Tarim Basin, Xinjiang, west China, it is important to predict the formation lithology for drilling bit optimization. Based on the conventional back propagation (BP) model, an improved BP model was proposed, with main modifications of back propagation of error, self-adapting algorithm, and activation function, also a prediction program was developed. The improved BP model was successfully applied to predicting the lithology of formations to be drilled in the Kela-2 gas field. 展开更多
关键词 Kela-2 gas field neural network improved back-propagation (BP) model log data lithology prediction
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Deep Convolution Neural Networks for Image-Based Android Malware Classification
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作者 Amel Ksibi Mohammed Zakariah +1 位作者 Latifah Almuqren Ala Saleh Alluhaidan 《Computers, Materials & Continua》 2025年第3期4093-4116,共24页
The analysis of Android malware shows that this threat is constantly increasing and is a real threat to mobile devices since traditional approaches,such as signature-based detection,are no longer effective due to the ... The analysis of Android malware shows that this threat is constantly increasing and is a real threat to mobile devices since traditional approaches,such as signature-based detection,are no longer effective due to the continuously advancing level of sophistication.To resolve this problem,efficient and flexible malware detection tools are needed.This work examines the possibility of employing deep CNNs to detect Android malware by transforming network traffic into image data representations.Moreover,the dataset used in this study is the CIC-AndMal2017,which contains 20,000 instances of network traffic across five distinct malware categories:a.Trojan,b.Adware,c.Ransomware,d.Spyware,e.Worm.These network traffic features are then converted to image formats for deep learning,which is applied in a CNN framework,including the VGG16 pre-trained model.In addition,our approach yielded high performance,yielding an accuracy of 0.92,accuracy of 99.1%,precision of 98.2%,recall of 99.5%,and F1 score of 98.7%.Subsequent improvements to the classification model through changes within the VGG19 framework improved the classification rate to 99.25%.Through the results obtained,it is clear that CNNs are a very effective way to classify Android malware,providing greater accuracy than conventional techniques.The success of this approach also shows the applicability of deep learning in mobile security along with the direction for the future advancement of the real-time detection system and other deeper learning techniques to counter the increasing number of threats emerging in the future. 展开更多
关键词 Android malware detection deep convolutional neural network(DCNN) image processing CIC-AndMal2017 dataset exploratory data analysis VGG16 model
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Application of Seismic Inversion Using Logging Data as Constraints in Coalfield 被引量:3
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作者 许永忠 潘冬明 +1 位作者 张宝水 崔若飞 《Journal of China University of Mining and Technology》 2004年第1期22-25,共4页
Seismic inversion and basic theory are briefly presented and the main idea of this method is introduced. Both non-linear wave equation inversion technique and Complete Utilization of Samples Information (CUSI) neural ... Seismic inversion and basic theory are briefly presented and the main idea of this method is introduced. Both non-linear wave equation inversion technique and Complete Utilization of Samples Information (CUSI) neural network analysis are used in lithological interpretation in Jibei coal field. The prediction results indicate that this method can provide reliable data for thin coal exploitation and promising area evaluation. 展开更多
关键词 seismic data inversion CUSI neural network wave impedance logging data thin coal seams
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End-to-End 2D Convolutional Neural Network Architecture for Lung Nodule Identification and Abnormal Detection in Cloud
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作者 Safdar Ali Saad Asad +2 位作者 Zeeshan Asghar Atif Ali Dohyeun Kim 《Computers, Materials & Continua》 SCIE EI 2023年第4期461-475,共15页
The extent of the peril associated with cancer can be perceivedfrom the lack of treatment, ineffective early diagnosis techniques, and mostimportantly its fatality rate. Globally, cancer is the second leading cause of... The extent of the peril associated with cancer can be perceivedfrom the lack of treatment, ineffective early diagnosis techniques, and mostimportantly its fatality rate. Globally, cancer is the second leading cause ofdeath and among over a hundred types of cancer;lung cancer is the secondmost common type of cancer as well as the leading cause of cancer-relateddeaths. Anyhow, an accurate lung cancer diagnosis in a timely manner canelevate the likelihood of survival by a noticeable margin and medical imagingis a prevalent manner of cancer diagnosis since it is easily accessible to peoplearound the globe. Nonetheless, this is not eminently efficacious consideringhuman inspection of medical images can yield a high false positive rate. Ineffectiveand inefficient diagnosis is a crucial reason for such a high mortalityrate for this malady. However, the conspicuous advancements in deep learningand artificial intelligence have stimulated the development of exceedinglyprecise diagnosis systems. The development and performance of these systemsrely prominently on the data that is used to train these systems. A standardproblem witnessed in publicly available medical image datasets is the severeimbalance of data between different classes. This grave imbalance of data canmake a deep learning model biased towards the dominant class and unableto generalize. This study aims to present an end-to-end convolutional neuralnetwork that can accurately differentiate lung nodules from non-nodules andreduce the false positive rate to a bare minimum. To tackle the problem ofdata imbalance, we oversampled the data by transforming available images inthe minority class. The average false positive rate in the proposed method isa mere 1.5 percent. However, the average false negative rate is 31.76 percent.The proposed neural network has 68.66 percent sensitivity and 98.42 percentspecificity. 展开更多
关键词 Convolutional neural networks medical image processing lung nodule identification data imbalance deep learning
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Web Page Recommendation Using Distributional Recurrent Neural Network
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作者 Chaithra G.M.Lingaraju S.Jagannatha 《Computer Systems Science & Engineering》 SCIE EI 2023年第4期803-817,共15页
In the data retrieval process of the Data recommendation system,the matching prediction and similarity identification take place a major role in the ontology.In that,there are several methods to improve the retrieving... In the data retrieval process of the Data recommendation system,the matching prediction and similarity identification take place a major role in the ontology.In that,there are several methods to improve the retrieving process with improved accuracy and to reduce the searching time.Since,in the data recommendation system,this type of data searching becomes complex to search for the best matching for given query data and fails in the accuracy of the query recommendation process.To improve the performance of data validation,this paper proposed a novel model of data similarity estimation and clustering method to retrieve the relevant data with the best matching in the big data processing.In this paper advanced model of the Logarithmic Directionality Texture Pattern(LDTP)method with a Metaheuristic Pattern Searching(MPS)system was used to estimate the similarity between the query data in the entire database.The overall work was implemented for the application of the data recommendation process.These are all indexed and grouped as a cluster to form a paged format of database structure which can reduce the computation time while at the searching period.Also,with the help of a neural network,the relevancies of feature attributes in the database are predicted,and the matching index was sorted to provide the recommended data for given query data.This was achieved by using the Distributional Recurrent Neural Network(DRNN).This is an enhanced model of Neural Network technology to find the relevancy based on the correlation factor of the feature set.The training process of the DRNN classifier was carried out by estimating the correlation factor of the attributes of the dataset.These are formed as clusters and paged with proper indexing based on the MPS parameter of similarity metric.The overall performance of the proposed work can be evaluated by varying the size of the training database by 60%,70%,and 80%.The parameters that are considered for performance analysis are Precision,Recall,F1-score and the accuracy of data retrieval,the query recommendation output,and comparison with other state-of-art methods. 展开更多
关键词 ONTOLOGY data mining in big data logarithmic directionality texture pattern metaheuristic pattern searching system distributional recurrent neural network query recommendation
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A Self-Organizing Memory Neural Network for Aerosol Concentration Prediction
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作者 Qiang Liu Yanyun Zou Xiaodong Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第6期617-637,共21页
Haze-fog,which is an atmospheric aerosol caused by natural or man-made factors,seriously affects the physical and mental health of human beings.PM2.5(a particulate matter whose diameter is smaller than or equal to 2.5... Haze-fog,which is an atmospheric aerosol caused by natural or man-made factors,seriously affects the physical and mental health of human beings.PM2.5(a particulate matter whose diameter is smaller than or equal to 2.5 microns)is the chief culprit causing aerosol.To forecast the condition of PM2.5,this paper adopts the related the meteorological data and air pollutes data to predict the concentration of PM2.5.Since the meteorological data and air pollutes data are typical time series data,it is reasonable to adopt a machine learning method called Single Hidden-Layer Long Short-Term Memory Neural Network(SSHL-LSTMNN)containing memory capability to implement the prediction.However,the number of neurons in the hidden layer is difficult to decide unless manual testing is operated.In order to decide the best structure of the neural network and improve the accuracy of prediction,this paper employs a self-organizing algorithm,which uses Information Processing Capability(IPC)to adjust the number of the hidden neurons automatically during a learning phase.In a word,to predict PM2.5 concentration accurately,this paper proposes the SSHL-LSTMNN to predict PM2.5 concentration.In the experiment,not only the hourly precise prediction but also the daily longer-term prediction is taken into account.At last,the experimental results reflect that SSHL-LSTMNN performs the best. 展开更多
关键词 Haze-fog PM2.5 forecasting time series data machine learning long shortterm MEMORY neural network SELF-ORGANIZING algorithm information processing CAPABILITY
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A new method for the prediction of network security situations based on recurrent neural network with gated recurrent unit 被引量:3
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作者 Wei Feng Yuqin Wu Yexian Fan 《International Journal of Intelligent Computing and Cybernetics》 EI 2020年第1期25-39,共15页
Purpose-The purpose of this paper is to solve the shortage of the existing methods for the prediction of network security situations(NSS).Because the conventional methods for the prediction of NSS,such as support vect... Purpose-The purpose of this paper is to solve the shortage of the existing methods for the prediction of network security situations(NSS).Because the conventional methods for the prediction of NSS,such as support vector machine,particle swarm optimization,etc.,lack accuracy,robustness and efficiency,in this study,the authors propose a new method for the prediction of NSS based on recurrent neural network(RNN)with gated recurrent unit.Design/methodology/approach-This method extracts internal and external information features from the original time-series network data for the first time.Then,the extracted features are applied to the deep RNN model for training and validation.After iteration and optimization,the accuracy of predictions of NSS will be obtained by the well-trained model,and the model is robust for the unstable network data.Findings-Experiments on bench marked data set show that the proposed method obtains more accurate and robust prediction results than conventional models.Although the deep RNN models need more time consumption for training,they guarantee the accuracy and robustness of prediction in return for validation.Originality/value-In the prediction of NSS time-series data,the proposed internal and external information features are well described the original data,and the employment of deep RNN model will outperform the state-of-the-arts models. 展开更多
关键词 Gated recurrent unit Internal and external information features network security situation Recurrent neural network Time-series data processing
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Application of Integrated Seismic Data Processing and Interpretation to Subtle Reservoir Survey 被引量:1
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作者 ZhouJinming 《Applied Geophysics》 SCIE CSCD 2004年第2期95-102,共8页
Nowadays, it becomes very urgent to find remain oil under the oil shortage worldwide.However, most of simple reservoirs have been discovered and those undiscovered are mostly complex structural, stratigraphic and lith... Nowadays, it becomes very urgent to find remain oil under the oil shortage worldwide.However, most of simple reservoirs have been discovered and those undiscovered are mostly complex structural, stratigraphic and lithologic ones. Summarized in this paper is the integrated seismic processing/interpretation technique established on the basis of pre-stack AVO processing and interpretation.Information feedbacks occurred between the pre-stack and post-stack processes so as to improve the accuracy in utilization of data and avoid pitfalls in seismic attributes. Through the integration of seismic data with geologic data, parameters that were most essential to describing hydrocarbon characteristics were determined and comprehensively appraised, and regularities of reservoir generation and distribution were described so as to accurately appraise reservoirs, delineate favorite traps and pinpoint wells. 展开更多
关键词 ubtle reservoir data processing INTERPRETATION ATTRIBUTE TRAP neural network
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Data Processing Methods of Flow Field Based on Artificial Lateral Line Pressure Sensors
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作者 Bing Sun Yi Xu +2 位作者 Shuhang Xie Dong Xu Yupu Liang 《Journal of Bionic Engineering》 SCIE EI CSCD 2022年第6期1797-1815,共19页
The estimation of the type and parameter of flow field is important for robotic fish.Recent estimation methods cannot meet the requirements of the robotic fish due to the lack of prior knowledge or the under-fitting o... The estimation of the type and parameter of flow field is important for robotic fish.Recent estimation methods cannot meet the requirements of the robotic fish due to the lack of prior knowledge or the under-fitting of the model.A processing method including data preprocessing,feature extraction,feature selection,flow type classification and flow field parameters estimation,is proposed based on the data of the pressure sensors in an artificial lateral line.Probabilistic Neural Network(PNN)is used to classify the flow field type and the Generalized Regressive Neural Network(GRNN)is the best choice for estimating the flow field parameters.Also,a few filtering methods for data preprocessing,three methods for feature selection and nine parameters estimation methods are analysis for choosing better method.The proposed method is verified by the experiments with both simulation and real data. 展开更多
关键词 Robotic fish Artificial lateral line data processing neural network
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A new method for high resolution well-control processing of post-stack seismic data
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作者 Wu Dakui Wu Zongwei Wu Yijia 《Natural Gas Industry B》 2020年第3期215-223,共9页
Increasing the resolution of seismic data has long been a major topic in seismic exploration.Due to the effect of high-frequency noises,traditional methods could only improve the resolution limitedly.To end this,this ... Increasing the resolution of seismic data has long been a major topic in seismic exploration.Due to the effect of high-frequency noises,traditional methods could only improve the resolution limitedly.To end this,this paper newly proposed a high-resolution seismic data processing method based on welleseismic combination after summarizing the research status on high resolution.Synthetic record and seismogram are similar in effective signals but dissimilar in noises.Their effective signals are regular and noises are irregular.And they are similar in adjacent frequency.Based on these“three-regularity”characteristics,the relationship between synthetic record and seismogram was established using the neural network algorithm.Then,the corresponding extrapolation algorithm was proposed based on the self-adaptive geological and geophysical variation of multi-layer network structure.And a model was established by virtue of this method and the theoretical simulation was carried out.In addition,it was tested from the aspects of frequency component and amplitude energy recovery,phase correction,regularity elimination and stochastic noise.And the following research results were obtained.First,this new method can extract high-frequency information as much as possible and remain middle and low-frequency effective information while eliminating the noises.Second,in this method,the idea of traditional methods to denoisefirst and then expand frequency is changed completely and the limitation of traditional methods is broken.It establishes the idea of expanding frequency and denoising simultaneously and increases the resolution to the uttermost.Third,this new method has been applied to a variety of reservoir descriptions and the high-resolution processing results have been improved significantly in precision and accuracy. 展开更多
关键词 Synthetic record Seismogram STACK High resolution neural network DENOISING Frequency expanding data processing
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基于多道卡尔曼滤波神经网络的无监督微地震去噪方法
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作者 张岩 张永雪 +4 位作者 魏子心 董宏丽 韩非 张林军 汪靖哲 《地球物理学报》 北大核心 2026年第1期353-365,共13页
微地震数据中有效信号的振幅、频率,及噪声具有显著的时变特征,当前微地震去噪方法中基于卡尔曼滤波方法高度依赖经验调参而影响应用效率,深度学习方法往往需要大量有效样本监督学习.针对以上问题,提出一种结合卡尔曼滤波与循环神经网... 微地震数据中有效信号的振幅、频率,及噪声具有显著的时变特征,当前微地震去噪方法中基于卡尔曼滤波方法高度依赖经验调参而影响应用效率,深度学习方法往往需要大量有效样本监督学习.针对以上问题,提出一种结合卡尔曼滤波与循环神经网络的无监督微地震数据去噪方法.首先,建立多道微地震数据的卡尔曼滤波状态预测与更新方程,充分利用多道相关性提高卡尔曼滤波参数的表征能力;其次,设计多道卡尔曼滤波状态预测与更新的RNN运算算子,通过链式梯度自动求取方式优化卡尔曼滤波的参数,构建基于循环神经网络模式的多道卡尔曼网络去噪;再次,结合无监督的微地震去噪训练方法,实现卡尔曼参数自动优化,避免有效数据标签的过度依赖;最后,通过理论正演与实际微地震数据的实验结果表明,本文方法在微地震去噪准确性与效率上优于传统卡尔曼滤波与变分自编码器等同类方法. 展开更多
关键词 微地震数据处理 卡尔曼滤波 循环神经网络 噪声压制 无监督网络
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基于nnUNet模型的冠脉CTA自动识别方法
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作者 杨雪荣 刘志童 +3 位作者 李晋芳 成思源 陈样新 阳盼 《自动化应用》 2026年第2期92-98,103,共8页
针对冠脉血管堵塞诊断依赖人工观察计算机断层扫描造影(CTA)二维切片图像,存在主观性强、专业要求高等问题,提出了基于nnUNet模型的冠脉血管自动分割方法与改进的三维重建方法。该方法依据冠脉CTA的血管占比少的图像特点,使用Foacl Los... 针对冠脉血管堵塞诊断依赖人工观察计算机断层扫描造影(CTA)二维切片图像,存在主观性强、专业要求高等问题,提出了基于nnUNet模型的冠脉血管自动分割方法与改进的三维重建方法。该方法依据冠脉CTA的血管占比少的图像特点,使用Foacl Loss损失函数替换交叉熵损失函数,并通过引入全连接的密集条件随机场(Dense CRF)解决分割后特征信息损失问题。针对原有的三维重建方法无法展示患者冠脉具体病灶区域与实时性差的问题,提出了一种组合式冠脉二维切片图像三维重建方法。最后,以医院提供的患者临床冠脉二维切片影像为数据集进行实验,证明了改进后的nnUNet模型相较于其他图像分割模型对冠脉血管的分割精度得到了有效提升。 展开更多
关键词 计算机断层扫描造影 卷积神经网络 医学影像处理 三维重建 损失函数 数据增强 条件随机场
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简支梁桥轻量化监测的状态评估方法研究
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作者 田石柱 陆一帆 刘晨光 《广西大学学报(自然科学版)》 北大核心 2026年第1期14-25,共12页
为了提升简支梁桥状态评估效率和评估智能化水平,提出基于准静态响应的桥梁正常使用状态的快速智能评估方法。首先,以车辆信息监测和关键截面的挠度监测为基础,建立轻量化监测体系;其次,建立以车辆信息和截面响应为输入、准静态挠度响... 为了提升简支梁桥状态评估效率和评估智能化水平,提出基于准静态响应的桥梁正常使用状态的快速智能评估方法。首先,以车辆信息监测和关键截面的挠度监测为基础,建立轻量化监测体系;其次,建立以车辆信息和截面响应为输入、准静态挠度响应为输出的3种机器学习模型,构建桥梁响应有限元代理模型;再次,提出基于逐次变分模态分解(SVMD)的准静态挠度曲线自适应提取方法,通过迭代分解、残差评估,自动确定最优模态分解个数;最后,通过损伤桥梁和未损桥梁的准静态响应曲线面积比,构建评估系数β和桥梁状态分级表,并通过简支箱梁桥的数值算例进行验证。结果表明:基于反向传播(BP)神经网络构建的有限元代理模型训练结果最优,决定系数(R^(2))为98%、均方根误差(RMSE)为0.0069;通过SVMD提取出的准静态挠度响应整体相对误差均小于2%,峰值相对误差均小于1%;将模型刚度折减成设计值的88%时,计算简支箱梁桥的β值为0.88,通过桥梁状态分级表评估桥梁的状态为一般,与设置的损伤状况一致,可初步判断桥梁的正常使用状态。 展开更多
关键词 轻量化监测 数据处理 机器学习 BP神经网络 准静态响应 状态评估
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Optimizing Big Data Retrieval and Job Scheduling Using Deep Learning Approaches
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作者 Bao Rong Chang Hsiu-Fen Tsai Yu-Chieh Lin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期783-815,共33页
Big data analytics in business intelligence do not provide effective data retrieval methods and job scheduling that will cause execution inefficiency and low system throughput.This paper aims to enhance the capability... Big data analytics in business intelligence do not provide effective data retrieval methods and job scheduling that will cause execution inefficiency and low system throughput.This paper aims to enhance the capability of data retrieval and job scheduling to speed up the operation of big data analytics to overcome inefficiency and low throughput problems.First,integrating stacked sparse autoencoder and Elasticsearch indexing explored fast data searching and distributed indexing,which reduces the search scope of the database and dramatically speeds up data searching.Next,exploiting a deep neural network to predict the approximate execution time of a job gives prioritized job scheduling based on the shortest job first,which reduces the average waiting time of job execution.As a result,the proposed data retrieval approach outperforms the previous method using a deep autoencoder and Solr indexing,significantly improving the speed of data retrieval up to 53%and increasing system throughput by 53%.On the other hand,the proposed job scheduling algorithmdefeats both first-in-first-out andmemory-sensitive heterogeneous early finish time scheduling algorithms,effectively shortening the average waiting time up to 5%and average weighted turnaround time by 19%,respectively. 展开更多
关键词 Stacked sparse autoencoder Elasticsearch distributed indexing data retrieval deep neural network job scheduling
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A Novel Agricultural Data Sharing Mode Based on Rice Disease Identification
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作者 Mengmeng ZHANG Xiujuan WANG +3 位作者 Mengzhen KANG Jing HUA Haoyu WANG Feiyue WANG 《Plant Diseases and Pests》 2024年第2期9-16,共8页
In this paper,a variety of classical convolutional neural networks are trained on two different datasets using transfer learning method.We demonstrated that the training dataset has a significant impact on the trainin... In this paper,a variety of classical convolutional neural networks are trained on two different datasets using transfer learning method.We demonstrated that the training dataset has a significant impact on the training results,in addition to the optimization achieved through the model structure.However,the lack of open-source agricultural data,combined with the absence of a comprehensive open-source data sharing platform,remains a substantial obstacle.This issue is closely related to the difficulty and high cost of obtaining high-quality agricultural data,the low level of education of most employees,underdeveloped distributed training systems and unsecured data security.To address these challenges,this paper proposes a novel idea of constructing an agricultural data sharing platform based on a federated learning(FL)framework,aiming to overcome the deficiency of high-quality data in agricultural field training. 展开更多
关键词 Rice disease and pest identification Convolutional neural networks distributed training Federated learning(FL) Open-source data sharing platform
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面向开放互联网的科学数据挖掘与理解
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作者 卢彬 甘小莺 +8 位作者 甘雨 唐顾 马婷晏 吴律文 赵泽 傅洛伊 金梦 王新兵 周成虎 《计算机学报》 北大核心 2026年第1期15-28,共14页
随着数据观测、采集手段的发展,科学大数据正快速增长,并推动着科研范式变革。然而,科学数据分散在互联网中各类数据仓储与个人数据库中形成了“数据孤岛”,难以有效整合与关联科学数据。为此,本文提出了一种面向开放互联网的科学数据... 随着数据观测、采集手段的发展,科学大数据正快速增长,并推动着科研范式变革。然而,科学数据分散在互联网中各类数据仓储与个人数据库中形成了“数据孤岛”,难以有效整合与关联科学数据。为此,本文提出了一种面向开放互联网的科学数据挖掘与理解方法,通过机器阅读各类互联网数据资源,自动识别科学数据并结构化抽取关键字段,实现对科学数据的高效发现与管理。具体来说,本文融合网页多视角信息设计了网页筛选器WebFlteri,通过融合网页DOM树的结构共现与语义相关实现对网页级特征理解与分类;此外,本文设计了基于节点异构关联的网页阅读器WebRadere,通过异构图网络的消息传递对网页关键信息进行结构化抽取,形成科学数据画像。本文采用了多个公开数据集进行实验性能评估:在网页分类方面,本文提出的WebFlteri相较于基线模型准确率提升了1.39%到3.71%、F1分数提升了1.42%到4.10%;在网页信息抽取方面,本文提出的WebRadere平均提升1.40%,在少训练样本情况下性能提升显著。更进一步,基于本文技术研究成果研制了面向地球科学领域的开放科学数据系统DataExpo,汇聚百万科学数据并提供了数据多维查询、地图查询等数据服务,已应用于“深时数字地球”国际大科学计划,推动了地球科学领域数据驱动范式研究。 展开更多
关键词 科学数据 网页数据挖掘 AI for Science 文本图神经网络 信息检索 自然语言处理
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基于多构型仿真数据的双螺杆挤出机螺杆建压过程
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作者 赵冲 毕超 +3 位作者 左仕博 殷德举 梁畅 郭显顺 《塑料科技》 北大核心 2026年第3期186-192,共7页
螺纹元件的导程大小与排列顺序直接决定建压特性,大导程元件前置时压力梯度呈“前陡后缓”特征,导程递减结构(模型1)通过最大化剪切耗散实现高效建压,可保障熔体均匀挤出,避免因压力不足导致的产品密度不均;而短导程前置或导程突变组合... 螺纹元件的导程大小与排列顺序直接决定建压特性,大导程元件前置时压力梯度呈“前陡后缓”特征,导程递减结构(模型1)通过最大化剪切耗散实现高效建压,可保障熔体均匀挤出,避免因压力不足导致的产品密度不均;而短导程前置或导程突变组合易引发负压区与流动分离,导致熔体滞留时间差异显著、剪切热分布异常,进而使产品出现熔接痕、力学性能波动等缺陷。因此,精准构建建压模型是预测压力分布、优化螺杆构型以提升产品质量稳定性的核心前提。研究采用多层感知机(MLP)神经网络,其通过非线性映射精准捕捉压力分布与工艺参数的复杂关联,在模型4与模型6测试集上,4 MPa压差下末段压力预测误差分别为3.5%和小于2.0%,能够准确刻画导程骤变区域的压力波动特征。结合3次样条插值,模型可将预测范围拓展至任意压差工况,有效满足多工况工艺设计需求,为双螺杆挤出机的实时控制与构型优化提供参考。 展开更多
关键词 双螺杆挤出机 建压过程 多构型仿真 MLP神经网络 压力分布
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A Novel Approach to Design Distribution Preserving Framework for Big Data 被引量:1
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作者 Mini Prince P.M.Joe Prathap 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期2789-2803,共15页
In several fields like financial dealing,industry,business,medicine,et cetera,Big Data(BD)has been utilized extensively,which is nothing but a collection of a huge amount of data.However,it is highly complicated along... In several fields like financial dealing,industry,business,medicine,et cetera,Big Data(BD)has been utilized extensively,which is nothing but a collection of a huge amount of data.However,it is highly complicated along with time-consuming to process a massive amount of data.Thus,to design the Distribution Preserving Framework for BD,a novel methodology has been proposed utilizing Manhattan Distance(MD)-centered Partition Around Medoid(MD–PAM)along with Conjugate Gradient Artificial Neural Network(CG-ANN),which undergoes various steps to reduce the complications of BD.Firstly,the data are processed in the pre-processing phase by mitigating the data repetition utilizing the map-reduce function;subsequently,the missing data are handled by substituting or by ignoring the missed values.After that,the data are transmuted into a normalized form.Next,to enhance the classification performance,the data’s dimensionalities are minimized by employing Gaussian Kernel(GK)-Fisher Discriminant Analysis(GK-FDA).Afterwards,the processed data is submitted to the partitioning phase after transmuting it into a structured format.In the partition phase,by utilizing the MD-PAM,the data are partitioned along with grouped into a cluster.Lastly,by employing CG-ANN,the data are classified in the classification phase so that the needed data can be effortlessly retrieved by the user.To analogize the outcomes of the CG-ANN with the prevailing methodologies,the NSL-KDD openly accessible datasets are utilized.The experiential outcomes displayed that an efficient result along with a reduced computation cost was shown by the proposed CG-ANN.The proposed work outperforms well in terms of accuracy,sensitivity and specificity than the existing systems. 展开更多
关键词 Big data artificial neural network fisher discriminant analysis distribution preserving framework manhattan distance
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