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A Deep Learning Approach for Fault Diagnosis in Centrifugal Pumps through Wavelet Coherent Analysis and S-Transform Scalograms with CNN-KAN
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作者 Muhammad Farooq Siddique Saif Ullah Jong-Myon Kim 《Computers, Materials & Continua》 2025年第8期3577-3603,共27页
Centrifugal Pumps(CPs)are critical machine components in many industries,and their efficient operation and reliable Fault Diagnosis(FD)are essential for minimizing downtime and maintenance costs.This paper introduces ... Centrifugal Pumps(CPs)are critical machine components in many industries,and their efficient operation and reliable Fault Diagnosis(FD)are essential for minimizing downtime and maintenance costs.This paper introduces a novel FD method to improve both the accuracy and reliability of detecting potential faults in such pumps.Theproposed method combinesWaveletCoherent Analysis(WCA)and Stockwell Transform(S-transform)scalograms with Sobel and non-local means filters,effectively capturing complex fault signatures from vibration signals.Using Convolutional Neural Network(CNN)for feature extraction,the method transforms these scalograms into image inputs,enabling the recognition of patterns that span both time and frequency domains.The CNN extracts essential discriminative features,which are then merged and passed into a Kolmogorov-Arnold Network(KAN)classifier,ensuring precise fault identification.The proposed approach was experimentally validated on diverse datasets collected under varying conditions,demonstrating its robustness and generalizability.Achieving classification accuracy of 100%,99.86%,and 99.92%across the datasets,this method significantly outperforms traditional fault detection approaches.These results underscore the potential to enhance CP FD,providing an effective solution for predictive maintenance and improving overall system reliability. 展开更多
关键词 Fault diagnosis centrifugal pump wavelet coherent analysis stockwell transform convolutional neural network Kolmogorov-Arnold network
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Transformers for Multi-Modal Image Analysis in Healthcare
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作者 Sameera V Mohd Sagheer Meghana K H +2 位作者 P M Ameer Muneer Parayangat Mohamed Abbas 《Computers, Materials & Continua》 2025年第9期4259-4297,共39页
Integrating multiple medical imaging techniques,including Magnetic Resonance Imaging(MRI),Computed Tomography,Positron Emission Tomography(PET),and ultrasound,provides a comprehensive view of the patient health status... Integrating multiple medical imaging techniques,including Magnetic Resonance Imaging(MRI),Computed Tomography,Positron Emission Tomography(PET),and ultrasound,provides a comprehensive view of the patient health status.Each of these methods contributes unique diagnostic insights,enhancing the overall assessment of patient condition.Nevertheless,the amalgamation of data from multiple modalities presents difficulties due to disparities in resolution,data collection methods,and noise levels.While traditional models like Convolutional Neural Networks(CNNs)excel in single-modality tasks,they struggle to handle multi-modal complexities,lacking the capacity to model global relationships.This research presents a novel approach for examining multi-modal medical imagery using a transformer-based system.The framework employs self-attention and cross-attention mechanisms to synchronize and integrate features across various modalities.Additionally,it shows resilience to variations in noise and image quality,making it adaptable for real-time clinical use.To address the computational hurdles linked to transformer models,particularly in real-time clinical applications in resource-constrained environments,several optimization techniques have been integrated to boost scalability and efficiency.Initially,a streamlined transformer architecture was adopted to minimize the computational load while maintaining model effectiveness.Methods such as model pruning,quantization,and knowledge distillation have been applied to reduce the parameter count and enhance the inference speed.Furthermore,efficient attention mechanisms such as linear or sparse attention were employed to alleviate the substantial memory and processing requirements of traditional self-attention operations.For further deployment optimization,researchers have implemented hardware-aware acceleration strategies,including the use of TensorRT and ONNX-based model compression,to ensure efficient execution on edge devices.These optimizations allow the approach to function effectively in real-time clinical settings,ensuring viability even in environments with limited resources.Future research directions include integrating non-imaging data to facilitate personalized treatment and enhancing computational efficiency for implementation in resource-limited environments.This study highlights the transformative potential of transformer models in multi-modal medical imaging,offering improvements in diagnostic accuracy and patient care outcomes. 展开更多
关键词 Multi-modal image analysis medical imaging deep learning image segmentation disease detection multi-modal fusion Vision transformers(ViTs) precision medicine clinical decision support
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A Hybrid CNN-Transformer Framework for Normal Blood Cell Classification:Towards Automated Hematological Analysis
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作者 Osama M.Alshehri Ahmad Shaf +7 位作者 Muhammad Irfan Mohammed M.Jalal Malik A.Altayar Mohammed H.Abu-Alghayth Humood Al Shmrany Tariq Ali Toufique A.Soomro Ali G.Alkhathami 《Computer Modeling in Engineering & Sciences》 2025年第7期1165-1196,共32页
Background:Accurate classification of normal blood cells is a critical foundation for automated hematological analysis,including the detection of pathological conditions like leukemia.While convolutional neural networ... Background:Accurate classification of normal blood cells is a critical foundation for automated hematological analysis,including the detection of pathological conditions like leukemia.While convolutional neural networks(CNNs)excel in local feature extraction,their ability to capture global contextual relationships in complex cellular morphologies is limited.This study introduces a hybrid CNN-Transformer framework to enhance normal blood cell classification,laying the groundwork for future leukemia diagnostics.Methods:The proposed architecture integrates pre-trained CNNs(ResNet50,EfficientNetB3,InceptionV3,CustomCNN)with Vision Transformer(ViT)layers to combine local and global feature modeling.Four hybrid models were evaluated on the publicly available Blood Cell Images dataset from Kaggle,comprising 17,092 annotated normal blood cell images across eight classes.The models were trained using transfer learning,fine-tuning,and computational optimizations,including cross-model parameter sharing to reduce redundancy by reusing weights across CNN backbones and attention-guided layer pruning to eliminate low-contribution layers based on attention scores,improving efficiency without sacrificing accuracy.Results:The InceptionV3-ViT model achieved a weighted accuracy of 97.66%(accounting for class imbalance by weighting each class’s contribution),a macro F1-score of 0.98,and a ROC-AUC of 0.998.The framework excelled in distinguishing morphologically similar cell types demonstrating robustness and reliable calibration(ECE of 0.019).The framework addresses generalization challenges,including class imbalance and morphological similarities,ensuring robust performance across diverse cell types.Conclusion:The hybrid CNN-Transformer framework significantly improves normal blood cell classification by capturing multi-scale features and long-range dependencies.Its high accuracy,efficiency,and generalization position it as a strong baseline for automated hematological analysis,with potential for extension to leukemia subtype classification through future validation on pathological samples. 展开更多
关键词 Acute leukemia automated diagnosis blood cell classification convolution neural networks deep learning fine-tuning hematologic malignancy hybrid deep learning architecture leukemia subtype classification medical image analysis transfer learning vision transformers
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The W transform and its improved methods for time-frequency analysis of seismic data 被引量:1
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作者 WANG Yanghua RAO Ying ZHAO Zhencong 《Petroleum Exploration and Development》 SCIE 2024年第4期886-896,共11页
The conventional linear time-frequency analysis method cannot achieve high resolution and energy focusing in the time and frequency dimensions at the same time,especially in the low frequency region.In order to improv... The conventional linear time-frequency analysis method cannot achieve high resolution and energy focusing in the time and frequency dimensions at the same time,especially in the low frequency region.In order to improve the resolution of the linear time-frequency analysis method in the low-frequency region,we have proposed a W transform method,in which the instantaneous frequency is introduced as a parameter into the linear transformation,and the analysis time window is constructed which matches the instantaneous frequency of the seismic data.In this paper,the W transform method is compared with the Wigner-Ville distribution(WVD),a typical nonlinear time-frequency analysis method.The WVD method that shows the energy distribution in the time-frequency domain clearly indicates the gravitational center of time and the gravitational center of frequency of a wavelet,while the time-frequency spectrum of the W transform also has a clear gravitational center of energy focusing,because the instantaneous frequency corresponding to any time position is introduced as the transformation parameter.Therefore,the W transform can be benchmarked directly by the WVD method.We summarize the development of the W transform and three improved methods in recent years,and elaborate on the evolution of the standard W transform,the chirp-modulated W transform,the fractional-order W transform,and the linear canonical W transform.Through three application examples of W transform in fluvial sand body identification and reservoir prediction,it is verified that W transform can improve the resolution and energy focusing of time-frequency spectra. 展开更多
关键词 time-frequency analysis W transform Wigner-Ville distribution matching pursuit energy focusing RESOLUTION
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Unified Neural Lexical Analysis Via Two-Stage Span Tagging
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作者 Yantuan Xian Yefen Zhu +3 位作者 Zhentao Yu Yuxin Huang Junjun Guo Yan Xiang 《CAAI Transactions on Intelligence Technology》 2025年第4期1254-1267,共14页
Lexical analysis is a fundamental task in natural language processing,which involves several subtasks,such as word segmentation(WS),part-of-speech(POS)tagging,and named entity recognition(NER).Recent works have shown ... Lexical analysis is a fundamental task in natural language processing,which involves several subtasks,such as word segmentation(WS),part-of-speech(POS)tagging,and named entity recognition(NER).Recent works have shown that taking advantage of relatedness between these subtasks can be beneficial.This paper proposes a unified neural framework to address these subtasks simultaneously.Apart from the sequence tagging paradigm,the proposed method tackles the multitask lexical analysis via two-stage sequence span classification.Firstly,the model detects the word and named entity boundaries by multilabel classification over character spans in a sentence.Then,the authors assign POS labels and entity labels for words and named entities by multi-class classification,respectively.Furthermore,a Gated Task Transformation(GTT)is proposed to encourage the model to share valuable features between tasks.The performance of the proposed model was evaluated on Chinese and Thai public datasets,demonstrating state-of-the-art results. 展开更多
关键词 gated task transformation lexical analysis multitask TWO-STAGE
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Enhancing Arabic Sentiment Analysis with Pre-Trained CAMeLBERT:A Case Study on Noisy Texts
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作者 Fay Aljomah Lama Aldhafeeri +3 位作者 Maha Alfadel Sultanh Alshahrani Qaisar Abbas Sarah Alhumoud 《Computers, Materials & Continua》 2025年第9期5317-5335,共19页
Dialectal Arabic text classifcation(DA-TC)provides a mechanism for performing sentiment analysis on recent Arabic social media leading to many challenges owing to the natural morphology of the Arabic language and its ... Dialectal Arabic text classifcation(DA-TC)provides a mechanism for performing sentiment analysis on recent Arabic social media leading to many challenges owing to the natural morphology of the Arabic language and its wide range of dialect variations.Te availability of annotated datasets is limited,and preprocessing of the noisy content is even more challenging,sometimes resulting in the removal of important cues of sentiment from the input.To overcome such problems,this study investigates the applicability of using transfer learning based on pre-trained transformer models to classify sentiment in Arabic texts with high accuracy.Specifcally,it uses the CAMeLBERT model fnetuned for the Multi-Domain Arabic Resources for Sentiment Analysis(MARSA)dataset containing more than 56,000 manually annotated tweets annotated across political,social,sports,and technology domains.Te proposed method avoids extensive use of preprocessing and shows that raw data provides better results because they tend to retain more linguistic features.Te fne-tuned CAMeLBERT model produces state-of-the-art accuracy of 92%,precision of 91.7%,recall of 92.3%,and F1-score of 91.5%,outperforming standard machine learning models and ensemble-based/deep learning techniques.Our performance comparisons against other pre-trained models,namely AraBERTv02-twitter and MARBERT,show that transformer-based architectures are consistently the best suited when dealing with noisy Arabic texts.Tis work leads to a strong remedy for the problems in Arabic sentiment analysis and provides recommendations on easy tuning of the pre-trained models to adapt to challenging linguistic features and domain-specifc tasks. 展开更多
关键词 Artifcial intelligence deep learning machine learning BERT CAMeLBERT natural language processing sentiment analysis transformer
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A logistic-Lasso-regression-based seismic fragility analysis method for electrical equipment considering structural and seismic parameter uncertainty
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作者 Cui Jiawei Che Ailan +1 位作者 Li Sheng Cheng Yongfeng 《Earthquake Engineering and Engineering Vibration》 2025年第1期169-186,共18页
Damage to electrical equipment in an earthquake can lead to power outage of power systems.Seismic fragility analysis is a common method to assess the seismic reliability of electrical equipment.To further guarantee th... Damage to electrical equipment in an earthquake can lead to power outage of power systems.Seismic fragility analysis is a common method to assess the seismic reliability of electrical equipment.To further guarantee the efficiency of analysis,multi-source uncertainties including the structure itself and seismic excitation need to be considered.A method for seismic fragility analysis that reflects structural and seismic parameter uncertainty was developed in this study.The proposed method used a random sampling method based on Latin hypercube sampling(LHS)to account for the structure parameter uncertainty and the group structure characteristics of electrical equipment.Then,logistic Lasso regression(LLR)was used to find the seismic fragility surface based on double ground motion intensity measures(IM).The seismic fragility based on the finite element model of an±1000 kV main transformer(UHVMT)was analyzed using the proposed method.The results show that the seismic fragility function obtained by this method can be used to construct the relationship between the uncertainty parameters and the failure probability.The seismic fragility surface did not only provide the probabilities of seismic damage states under different IMs,but also had better stability than the fragility curve.Furthermore,the sensitivity analysis of the structural parameters revealed that the elastic module of the bushing and the height of the high-voltage bushing may have a greater influence. 展开更多
关键词 seismic fragility UNCERTAINTY logistic lasso regression ±1000 kV main transformer sensitivity analysis
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Topology Data Analysis-Based Error Detection for Semantic Image Transmission with Incremental Knowledge-Based HARQ
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作者 Ni Fei Li Rongpeng +1 位作者 Zhao Zhifeng Zhang Honggang 《China Communications》 2025年第1期235-255,共21页
Semantic communication(SemCom)aims to achieve high-fidelity information delivery under low communication consumption by only guaranteeing semantic accuracy.Nevertheless,semantic communication still suffers from unexpe... Semantic communication(SemCom)aims to achieve high-fidelity information delivery under low communication consumption by only guaranteeing semantic accuracy.Nevertheless,semantic communication still suffers from unexpected channel volatility and thus developing a re-transmission mechanism(e.g.,hybrid automatic repeat request[HARQ])becomes indispensable.In that regard,instead of discarding previously transmitted information,the incremental knowledge-based HARQ(IK-HARQ)is deemed as a more effective mechanism that could sufficiently utilize the information semantics.However,considering the possible existence of semantic ambiguity in image transmission,a simple bit-level cyclic redundancy check(CRC)might compromise the performance of IK-HARQ.Therefore,there emerges a strong incentive to revolutionize the CRC mechanism,thus more effectively reaping the benefits of both SemCom and HARQ.In this paper,built on top of swin transformer-based joint source-channel coding(JSCC)and IK-HARQ,we propose a semantic image transmission framework SC-TDA-HARQ.In particular,different from the conventional CRC,we introduce a topological data analysis(TDA)-based error detection method,which capably digs out the inner topological and geometric information of images,to capture semantic information and determine the necessity for re-transmission.Extensive numerical results validate the effectiveness and efficiency of the proposed SC-TDA-HARQ framework,especially under the limited bandwidth condition,and manifest the superiority of TDA-based error detection method in image transmission. 展开更多
关键词 error detection incremental knowledgebased HARQ joint source-channel coding semantic communication swin transformer topological data analysis
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Variational Mode Decomposition-Informed Empirical Wavelet Transform for Electric Vibrator Noise Analysis
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作者 Zhenyu Xu Zhangwei Chen 《Journal of Applied Mathematics and Physics》 2024年第6期2320-2332,共13页
Electric vibrators find wide applications in reliability testing, waveform generation, and vibration simulation, making their noise characteristics a topic of significant interest. While Variational Mode Decomposition... Electric vibrators find wide applications in reliability testing, waveform generation, and vibration simulation, making their noise characteristics a topic of significant interest. While Variational Mode Decomposition (VMD) and Empirical Wavelet Transform (EWT) offer valuable support for studying signal components, they also present certain limitations. This article integrates the strengths of both methods and proposes an enhanced approach that integrates VMD into the frequency band division principle of EWT. Initially, the method decomposes the signal using VMD, determining the mode count based on residuals, and subsequently employs EWT decomposition based on this information. This addresses mode aliasing issues in the original method while capitalizing on VMD’s adaptability. Feasibility was confirmed through simulation signals and ultimately applied to noise signals from vibrators. Experimental results demonstrate that the improved method not only resolves EWT frequency band division challenges but also effectively decomposes signal components compared to the VMD method. 展开更多
关键词 Electric Vibrator Noise analysis Signal Decomposing Variational Mode Decomposition Empirical Wavelet transform
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Study on Rhizome Crops by Fourier Transform Infrared Spectroscopy Combined with Wavelet Analysis
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作者 任静 刘刚 +4 位作者 赵兴祥 赵帅群 欧全宏 徐娟 胡见飞 《Agricultural Science & Technology》 CAS 2015年第7期1522-1526,共5页
In order to distinguish 8 kinds of rhizome crops, the 40 samples were studied by Fourier transform infrared spectroscopy (FTIR) combined with wavelet transform (WT), principal component analysis (PCA) and hieram... In order to distinguish 8 kinds of rhizome crops, the 40 samples were studied by Fourier transform infrared spectroscopy (FTIR) combined with wavelet transform (WT), principal component analysis (PCA) and hieramhical cluster analysis (HCA). The results showed that the infrared spectra were similar on the whole, but there were differences in peak position, peak shape and peak absorption intensity in the range of 1 800-700 cm-1. The infrared spectra in the range of 1 800-700 cm-1 were selected to perform continuous wavelet transform (CWT) and discrete wavelet transform (DWT). The 15th-Ievel decomposition coefficients of CWT and the 5=-level detail coefficients of DWT were classified by PCA and HCA. The cumulative contri- bution rates of the first three principal components of CWT and DWT were 93.12% and 89.78%, respectively. The accurate recognition rates of PCA and HCA were all 100%. It is proved that FTIR combined with WT can be used to distinguish different kinds of rhizome crops. 展开更多
关键词 FTIR Rhizome crop Wavelet transform Principal component analysis Hierarchical cluster analysis
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ELECTROCHEMICAL NOISE ANALYSIS OF PURE ALUMINUM IN SODIUM CHLORIDE SOLUTION WITH WAVELET TRANSFORM TECHNIQUE 被引量:9
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作者 Z. Zhang, Q.D. Zhong, J.Q. Zhang, Y.L. Cheng, F.H. Cao, J.M. and C.N. CaoDepartment of Chemistry, Zhejiang University, Hangzhou 310027, ChinaElectrochemical Research Group, Shanghai University of Electric Power, Shanghai 200090, ChinaState Key Laboratory 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2002年第3期272-278,共7页
Wavelet transforms (WT) are proposed as an alternative tool to overcome the limitations of Fourier transforms (FFT) in the analysis of electrochemical noise (EN) data. The most relevant feature of this method of analy... Wavelet transforms (WT) are proposed as an alternative tool to overcome the limitations of Fourier transforms (FFT) in the analysis of electrochemical noise (EN) data. The most relevant feature of this method of analysis is its capability of decomposing electrochemical noise records into different sets of wavelet coefficients, which contain information about the time scale characteristic of the associated corrosion event. In this context, the potential noise fluctuations during the free corrosion of pure aluminum in sodium chloride solution was recorded and analyzed with wavelet transform technique. The typical results showed that the EN signal is composed of distinct type of events, which can be classified according to their scales, i.e. their time constants. Meanwhile, the energy distribution plot (EDP) can be used as 'fingerprints' of EN signals and can be very useful for analyzing EN data in the future. 展开更多
关键词 electrochemical noise wavelet analysis Fourier transforms CORROSION pure aluminum
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NYFR output pulse radar signal TOA analysis using extended Fourier transform and its TOA estimation 被引量:7
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作者 Zhaoyang Qiu Pei Wang +1 位作者 Jun Zhu Bin Tang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第2期212-223,共12页
Nyquist folding receiver (NYFR) is a typical wideband analog-to-information architecture. Focusing on the non-cooperative receiving, the pulse radar signal intercepted by the NYFR in time domain is analyzed. The NYFR ... Nyquist folding receiver (NYFR) is a typical wideband analog-to-information architecture. Focusing on the non-cooperative receiving, the pulse radar signal intercepted by the NYFR in time domain is analyzed. The NYFR outputs under different input conditions are investigated based on the extended Fourier transform (EFT) and the sampling theorem. Combining with the characteristic of the NYFR output in time domain, a new time of arrival (TOA) estimation method based on the energy envelope and the wavelet transform is proposed. The proposed estimation method can be adapted for the non-cooperative situation. It has no requirement for prior information to determine the threshold and is not necessary to transform the signal into baseband. Simulation results prove the correctness of the NYFR output expressions and show the efficacy of the proposed estimation method. © 2017 Beijing Institute of Aerospace Information. 展开更多
关键词 Fourier transforms RADAR Time domain analysis Wavelet transforms
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基于改进时间融合Transformers的中国大豆需求预测方法
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作者 刘佳佳 秦晓婧 +5 位作者 李乾川 许世卫 赵继春 王一罡 熊露 梁晓贺 《智慧农业(中英文)》 2025年第4期187-199,共13页
[目的/意义]精准预测大豆需求对保障国家粮食安全、优化产业决策与应对国际贸易变局有着重要的现实意义,而利用时间融合Transformers(Temporal Fusion Transformers,TFT)模型开展中国大豆需求预测时,在特征交互层与注意力权重分配等方... [目的/意义]精准预测大豆需求对保障国家粮食安全、优化产业决策与应对国际贸易变局有着重要的现实意义,而利用时间融合Transformers(Temporal Fusion Transformers,TFT)模型开展中国大豆需求预测时,在特征交互层与注意力权重分配等方面仍存在一定局限。为此,亟需探索一种基于改进TFT模型的预测方法,以提升需求预测的准确性与可解释性。[方法]本研究将深度学习的TFT模型应用到中国大豆需求预测中,提出了一种基于多层动态特征交互(Multi-layer Dynamic Feature Interaction,MDFI)与自适应注意力权重优化(Adaptive Attention Weight Optimization,AAWO)改进的MA-TFT(Improved TFT Model Based on MDFI and AAWO)模型。对包含1980—2024年4652个相关指标的中国大豆需求分析数据集进行数据预处理和特征工程,设计实验将MA-TFT模型分别与自回归差分移动平均模型(Autoregressive Integrated Moving Average Model,ARIMA)、长短期记忆网络(Long Short-Term Memory,LSTM)模型及TFT模型进行预测性能对比,进行了消融实验,同时利用SHAP(SHapley Additive exPlanations)工具可解释性分析影响中国大豆需求的关键特征变量,开展了未来10年的中国大豆需求量预测。[结果和讨论]MA-TFT模型的均方误差(Mean Squared Error,MSE)、平均绝对百分比误差(Mean Absolute Percentage Error,MAPE)分别为0.036和5.89%,决定系数R^(2)为0.91,均高于对比模型,均方根误差(Root Mean Square Error,RMSE)和MAPE分别较基准模型TFT累计降低21.84%和3.44%,表明改进TFT的MA-TFT模型能够捕捉特征间复杂关系,提升预测性能;研究利用SHAP工具可解释性分析发现,MA-TFT模型对影响中国大豆需求关键特征变量的解释稳定性较高;预计2025、2030和2034年中国大豆需求量分别达到11799万吨、11033万吨和11378万吨。[结论]基于改进TFT的MA-TFT模型方法为解决现有大豆需求预测方法精度不足、可解释性不强的实际问题提供了解决思路,也为其他农产品时间序列预测的方法优化与应用提供了参考和借鉴。 展开更多
关键词 时间融合transformers(TFT) 大豆需求预测 多层动态特征交互 自适应注意力权重优化 可解释性分析
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SIGNAL FEATURE EXTRACTION BASED UPON INDEPENDENT COMPONENT ANALYSIS AND WAVELET TRANSFORM 被引量:7
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作者 JiZhong JinTao QinShuren 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第1期123-126,共4页
It is an important precondition for machine fault diagnosis that vibrationsignal can be extracted effectively. Based on the characteristic of noise interfused during thecourse of sampling vibration signal, independent... It is an important precondition for machine fault diagnosis that vibrationsignal can be extracted effectively. Based on the characteristic of noise interfused during thecourse of sampling vibration signal, independent component analysis (ICA) method is combined withwavelet to de-noise. Firstly, The sampled signal can be separated with ICA, then the function offrequency band chosen with multi-resolution wavelet transform can be used to judge whether thestochastic disturbance singular signal is interfused. By these ways, the vibration signals can beextracted effectively, which provides favorable condition for subsequent feature detection ofvibration signal and fault diagnosis. 展开更多
关键词 Independent component analysis (ICA) Wavelet transform DE-NOISING FAULTDIAGNOSIS Feature extraction
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Carbonization mechanism of bamboo(phyllostachys)by means of Fourier Transform Infrared and elemental analysis 被引量:14
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作者 ZUO Song-lin GAO Shang-yu +1 位作者 YUAN Xi-gen XU Bo-sen 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第1期75-79,共5页
Bamboo was carbonized at different temperatures ranging from 200℃to 600℃.The dependence of the change of hemicellulose,cellulose,and lignin on the temperature was investigated by means of elemental analysis and Four... Bamboo was carbonized at different temperatures ranging from 200℃to 600℃.The dependence of the change of hemicellulose,cellulose,and lignin on the temperature was investigated by means of elemental analysis and Fourier Transform Infrared(FTIR)spectra of the residual solid products.The results showed:(1)Below 200℃,hemicellulose in bamboo was de-composed and a large amount of hydroxyl groups are dislocated from hemicellulose and cellulose,accompanied by the evolu-tion of water to escape.(2)200℃-250℃,cellulose in bamboo was drastically decomposed whereas the net structure of lignin keep stable,with the except of the dislocation of methoxyl groups from lignin.(3)250℃~400℃,the net structure of lignin col-lapse,up to 400’℃,followed by that the more position in aryl groups are substituted.(4)For bamboo carbonization,the aroma-tization of residual carbon has approximately completed at the temperature as high as 600℃.But the fusion of aromatic rings possibly does not occur. 展开更多
关键词 BAMBOO CARBONIZATION Fourier transform infrared Elemental analysis
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New homotopy analysis transform method for solving the discontinued problems arising in nanotechnology 被引量:4
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作者 M.M.Khader Sunil Kumar S.Abbasbandy 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第11期135-139,共5页
We present a new reliable analytical study for solving the discontinued problems arising in nanotechnology. Such problems are presented as nonlinear differential-difference equations. The proposed method is based on t... We present a new reliable analytical study for solving the discontinued problems arising in nanotechnology. Such problems are presented as nonlinear differential-difference equations. The proposed method is based on the Laplace trans- form with the homotopy analysis method (HAM). This method is a powerful tool for solving a large amount of problems. This technique provides a series of functions which may converge to the exact solution of the problem. A good agreement between the obtained solution and some well-known results is obtained. 展开更多
关键词 discretized mKdV lattice equation nonlinear differential-difference equations Laplace transform homotopy analysis transform method
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Mathematic Models for Analysis of Quality Components in Sugarcane Juice with Fourier Transform Near Infrared Spectroscopy 被引量:4
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作者 CAOGan TANZhong-wen 《Agricultural Sciences in China》 CAS CSCD 2003年第2期190-194,共5页
With the technique of Fourier transform near infrared (FT-NIR) spectroscopy, the calibration models for quantitative analysis of sucrose and polarization in sugarcane juice were developed by using transmission mode an... With the technique of Fourier transform near infrared (FT-NIR) spectroscopy, the calibration models for quantitative analysis of sucrose and polarization in sugarcane juice were developed by using transmission mode and calibrating with partial least square (PLS) algorithm. The determination coefficients (R2) of the predicted models for sucrose and polarization in juice were 0. 9980 and 0. 9979 respectively; the root mean square errors of cross validation (RMSECV) were 0. 143 and 0. 155% for sucrose and polarization in juice respectively. The predictive errors measured by FT-NIR were close to those by routine laboratory methods. The results demonstrated that the FT-NIR methods had high accuracy and they were able to replace the routine laboratory analysis. It was also demonstrated that as a rapid and accurate measurement, the FT-NIR technique had potential applications in quality control of mill sugarcane, establishment of payment system based on sugarcane quality, and selection of clones in sugarcane breeding. 展开更多
关键词 Fourier transform near infrared spectroscopy Quantitative analysis SUGARCANE SUCROSE
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RESEARCH OF WAVELET TRANSFORM INSTRUMENT SYSTEM FOR SIGNAL ANALYSIS 被引量:12
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作者 Qin Shuren Chen Zhikui +3 位作者 Tang Baoping Yang Changqi Xu Mingtao He Hui (Test Center, Chongqing University) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2000年第2期114-121,共8页
After brief describing the Principle of wavelet transform (WT) of signals, a new signals analysis system based on wavelet transform is introduced. The design and development of the instryment of wavelet transform are ... After brief describing the Principle of wavelet transform (WT) of signals, a new signals analysis system based on wavelet transform is introduced. The design and development of the instryment of wavelet transform are described. A number of practical uses of this system demonstrate that wavelet transform system is specially functional in identifying and processing impulse, singular and non-smooth signals, so that it should be evaluated the most advanced signal analyzing system. 展开更多
关键词 Wavelet transform Signal analysis Instrument
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Spectroscopic Analysis of Structural Transformation in Biodiesel Oxidation 被引量:4
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作者 Wu Jiang Chen Boshui +1 位作者 Fang Jianhua Wang Jiu 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2013年第3期28-32,共5页
The oxidation behavior of three biodiesels of different origins,viz.rapeseed oil derived biodiesel,soybean oil derived biodiesel and waste oil based biodiesel,were tested on an oxidation tester.The chemical compositio... The oxidation behavior of three biodiesels of different origins,viz.rapeseed oil derived biodiesel,soybean oil derived biodiesel and waste oil based biodiesel,were tested on an oxidation tester.The chemical compositions of the biodiesels were characterized by gas chromatography.Thereafter,the structural transformation of fatty acid methyl ester(FAME)of the biodiesels was analyzed by an infrared spectrometer and an ultraviolet absorption spectrometer.The results demonstrated that the oxidation behavior of biodiesels of different origins was closely related to the composition and distribution of FAMEs.Higher concentration of unsaturated FAME with multi-double bonds exhibited poorer oxidation resistance.Furthermore,cis-trans isomerization transformation occurred in the unsaturated FAME molecules and conjugated double-bond produced during the oxidation process of biodiesel.Greater cis-trans variations corresponded to deeper oxidation degree.The higher the content of unsaturated FAME with multi-double bonds in a biodiesel,the more the conjugated double bonds was formed. 展开更多
关键词 BIODIESEL OXIDATION structural transformation spectroscopic analysis
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Population genomic analysis reveals key genetic variations and the driving force for embryonic callus induction capability in maize
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作者 Peng Liu Langlang Ma +8 位作者 Siyi Jian Yao He Guangsheng Yuan Fei Ge Zhong Chen Chaoying Zou Guangtang Pan Thomas Lübberstedt Yaou Shen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2178-2195,共18页
Genetic transformation has been an effective technology for improving the agronomic traits of maize.However,it is highly reliant on the use of embryonic callus(EC)and shows a serious genotype dependence.In this study,... Genetic transformation has been an effective technology for improving the agronomic traits of maize.However,it is highly reliant on the use of embryonic callus(EC)and shows a serious genotype dependence.In this study,we performed genomic sequencing for 80 core maize germplasms and constructed a high-density genomic variation map using our newly developed pipeline(MQ2Gpipe).Based on the induction rate of EC(REC),these inbred lines were categorized into three subpopulations.The low-REC germplasms displayed more abundant genetic diversity than the high-REC germplasms.By integrating a genome-wide selective signature screen and region-based association analysis,we revealed 95.23 Mb of selective regions and 43 REC-associated variants.These variants had phenotypic variance explained values ranging between 21.46 and 49.46%.In total,103 candidate genes were identified within the linkage disequilibrium regions of these REC-associated loci.These genes mainly participate in regulation of the cell cycle,regulation of cytokinesis,and other functions,among which MYB15 and EMB2745 were located within the previously reported QTL for EC induction.Numerous leaf area-associated variants with large effects were closely linked to several REC-related loci,implying a potential synergistic selection of REC and leaf size during modern maize breeding. 展开更多
关键词 MAIZE genetic transformation embryonic callus selective signal association analysis
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