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Defect Detection Model Using Time Series Data Augmentation and Transformation
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作者 Gyu-Il Kim Hyun Yoo +1 位作者 Han-Jin Cho Kyungyong Chung 《Computers, Materials & Continua》 SCIE EI 2024年第2期1713-1730,共18页
Time-series data provide important information in many fields,and their processing and analysis have been the focus of much research.However,detecting anomalies is very difficult due to data imbalance,temporal depende... Time-series data provide important information in many fields,and their processing and analysis have been the focus of much research.However,detecting anomalies is very difficult due to data imbalance,temporal dependence,and noise.Therefore,methodologies for data augmentation and conversion of time series data into images for analysis have been studied.This paper proposes a fault detection model that uses time series data augmentation and transformation to address the problems of data imbalance,temporal dependence,and robustness to noise.The method of data augmentation is set as the addition of noise.It involves adding Gaussian noise,with the noise level set to 0.002,to maximize the generalization performance of the model.In addition,we use the Markov Transition Field(MTF)method to effectively visualize the dynamic transitions of the data while converting the time series data into images.It enables the identification of patterns in time series data and assists in capturing the sequential dependencies of the data.For anomaly detection,the PatchCore model is applied to show excellent performance,and the detected anomaly areas are represented as heat maps.It allows for the detection of anomalies,and by applying an anomaly map to the original image,it is possible to capture the areas where anomalies occur.The performance evaluation shows that both F1-score and Accuracy are high when time series data is converted to images.Additionally,when processed as images rather than as time series data,there was a significant reduction in both the size of the data and the training time.The proposed method can provide an important springboard for research in the field of anomaly detection using time series data.Besides,it helps solve problems such as analyzing complex patterns in data lightweight. 展开更多
关键词 Defect detection time series deep learning data augmentation data transformation
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Digital Transformation of Enterprise Human Resource Management Enabled by Big Data
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作者 Zhefan Zhuang 《Proceedings of Business and Economic Studies》 2024年第2期60-65,共6页
With the continuous development of big data technology,the digital transformation of enterprise human resource management has become a development trend.Human resources is one of the most important resources of enterp... With the continuous development of big data technology,the digital transformation of enterprise human resource management has become a development trend.Human resources is one of the most important resources of enterprises,which is crucial to the competitiveness of enterprises.Enterprises need to attract,retain,and motivate excellent employees,thereby enhancing the innovation ability of enterprises and improving competitiveness and market share in the market.To maintain advantages in the fierce market competition,enterprises need to adopt more scientific and effective human resource management methods to enhance organizational efficiency and competitiveness.At the same time,this paper analyzes the dilemma faced by enterprise human resource management,points out the new characteristics of enterprise human resource management enabled by big data,and puts forward feasible suggestions for enterprise digital transformation. 展开更多
关键词 Big data Digital transformation Enterprise management Human resource management
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CNN-Transformer结合对比学习的高光谱与LiDAR数据协同分类
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作者 吴海滨 戴诗语 +2 位作者 王爱丽 岩堀祐之 于效宇 《光学精密工程》 EI CAS CSCD 北大核心 2024年第7期1087-1100,共14页
针对高光谱图像(hyperspectral images,HSI)与LiDAR数据多模态分类任务中的跨模态信息表达和特征对齐等问题,提出一种基于对比学习CNN-Transformer高光谱和LiDAR数据协同分类网络(Contrastive Learning based CNNTransformer Network,CL... 针对高光谱图像(hyperspectral images,HSI)与LiDAR数据多模态分类任务中的跨模态信息表达和特征对齐等问题,提出一种基于对比学习CNN-Transformer高光谱和LiDAR数据协同分类网络(Contrastive Learning based CNNTransformer Network,CLCT-Net)。CLCT-Net通过由ConvNeXt V2 Block构成的共有特征提取模块,获得不同模态间的共性特征,解决异构传感器数据之间语义对齐的问题。构建了包含空间-通道分支和光谱上下文分支的双分支HSI编码器,以及结合频域自注意力机制的LiDAR编码器,以获取更丰富的特征表示。利用集成对比学习进行分类,进一步提升多模态数据协同分类的精度。在Houston 2013和Trento数据集上的实验结果表明,相较于其他高光谱图像和Li‐DAR数据分类模型,本文所提模型获得了更高的地物分类精度,分别达到了92.01%和98.90%,实现了跨模态数据特征的深度挖掘和协同提取。 展开更多
关键词 高光谱图像 激光雷达数据 transformER 卷积神经网络 对比学习
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基于Transformer的司法文书命名实体识别方法
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作者 王颖洁 张程烨 +1 位作者 白凤波 汪祖民 《计算机科学》 CSCD 北大核心 2024年第S01期113-121,共9页
命名实体识别是自然语言处理领域的关键任务之一,是实现下游任务的基础。目前针对司法领域的相关研究相对较少,司法系统的信息化和智能化转型仍有许多问题亟需解决。相比其他领域的文本,司法文书存在专业性强、语料资源少等局限,导致现... 命名实体识别是自然语言处理领域的关键任务之一,是实现下游任务的基础。目前针对司法领域的相关研究相对较少,司法系统的信息化和智能化转型仍有许多问题亟需解决。相比其他领域的文本,司法文书存在专业性强、语料资源少等局限,导致现有的司法文书识别结果较低。因此,从以下3方面开展研究:首先,提出了一种多标签层级迭代的文本标注方式,可以对原始司法文书文本进行自动化标注,同时有效地提升司法文书命名实体识别任务的实体识别效果;其次,提出了一种交融式的Transformer神经网络模型,对汉字固有属性的深层特征进行了充分利用,用于对司法文书进行命名实体识别;最后,对所提出的标注方法和模型与其他神经网络模型进行了对比实验。所提出的文本标注方式可以较为准确地实现司法文书的标注任务;同时,所提出的模型在通用数据集中相对于对照模型有较大的提高,并在司法领域数据集中取得了良好的效果。 展开更多
关键词 自然语言处理 数据标注 transformer模型 深度学习 司法信息化
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基于生成对抗Transformer的电力负荷数据异常检测
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作者 陆旦宏 范文尧 +3 位作者 杨婷 倪敏珏 李思琦 朱晓 《电力工程技术》 北大核心 2024年第1期157-164,共8页
电力负荷异常数据将给电力系统规划、负荷预测以及用能分析等带来较大的负面影响,因此亟须对负荷数据异常进行检测与识别。首先,针对电力负荷数据异常分类、原因及其特征开展分析。其次,改进传统Transformer编码器结构,采用多头注意力... 电力负荷异常数据将给电力系统规划、负荷预测以及用能分析等带来较大的负面影响,因此亟须对负荷数据异常进行检测与识别。首先,针对电力负荷数据异常分类、原因及其特征开展分析。其次,改进传统Transformer编码器结构,采用多头注意力层代替掩码多头注意力层,同时移除前馈网络,以提高模型对负荷时序序列的全局注意力。基于生成对抗网络(generative adversarial networks,GAN)生成器与判别器的博弈结构,提出一种改进的GAN-Transformer模型,以更好地捕捉趋势性特征并加速模型收敛。然后,引入多阶段映射与训练方法,综合焦点分数打分机制,通过分阶段负荷序列重构帮助模型更好地提取负荷数据异常特征。最后,算例分析结果表明,GAN-Transformer模型在负荷数据异常检测精确率、召回率、F_(1)值以及训练时间方面均具有更优的性能,验证了所提方法的有效性和优越性。文中研究工作为基于深度学习进一步实现电力负荷数据异常分类与数据修复提供了有益参考。 展开更多
关键词 电力负荷数据 数据异常检测 生成对抗网络(GAN)-transformer 多阶段训练与映射 焦点分数 序列重构
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融合Transformer和卷积LSTM的轨迹分类网络
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作者 夏英 陈航 《重庆邮电大学学报(自然科学版)》 CSCD 北大核心 2024年第1期29-38,共10页
为了减少原始轨迹数据的噪声,充分提取轨迹的时空特征,提高基于轨迹数据的交通模式分类精度,提出一种融合堆叠降噪自编码器、Transformer和卷积长短期记忆网络的轨迹分类网络(networks fusing stacked denoising auto-encoder, Transfor... 为了减少原始轨迹数据的噪声,充分提取轨迹的时空特征,提高基于轨迹数据的交通模式分类精度,提出一种融合堆叠降噪自编码器、Transformer和卷积长短期记忆网络的轨迹分类网络(networks fusing stacked denoising auto-encoder, Transformer and ConvLSTM,SDAETC)。通过堆叠降噪自编码器减少原始轨迹数据中的噪声;利用结合了Transformer的递归图自编码器,提取到更为丰富的时间特征,同时利用特征图自编码器提取空间特征;改进卷积长短期记忆网络,充分提取轨迹中的时空特征,并与提取到的时间特征和空间特征相融合,从而实现交通模式分类。实验结果表明,提出的SDAETC与基线模型相比,在GeoLife和SHL数据集上的准确率分别提升了1.8%和2%。此外,消融实验结果和模型训练时间分析表明,引入堆叠降噪自编码器、Transfomer和ConvLSTM虽然增加了时间消耗,但是对分类精度有积极贡献。 展开更多
关键词 轨迹数据 交通方式分类 时空特征 堆叠降噪自编码器 transformER 卷积长短期记忆网络
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Logformer: Cascaded Transformer for System Log Anomaly Detection
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作者 Feilu Hang Wei Guo +3 位作者 Hexiong Chen Linjiang Xie Chenghao Zhou Yao Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期517-529,共13页
Modern large-scale enterprise systems produce large volumes of logs that record detailed system runtime status and key events at key points.These logs are valuable for analyzing performance issues and understanding th... Modern large-scale enterprise systems produce large volumes of logs that record detailed system runtime status and key events at key points.These logs are valuable for analyzing performance issues and understanding the status of the system.Anomaly detection plays an important role in service management and system maintenance,and guarantees the reliability and security of online systems.Logs are universal semi-structured data,which causes difficulties for traditional manual detection and pattern-matching algorithms.While some deep learning algorithms utilize neural networks to detect anomalies,these approaches have an over-reliance on manually designed features,resulting in the effectiveness of anomaly detection depending on the quality of the features.At the same time,the aforementioned methods ignore the underlying contextual information present in adjacent log entries.We propose a novel model called Logformer with two cascaded transformer-based heads to capture latent contextual information from adjacent log entries,and leverage pre-trained embeddings based on logs to improve the representation of the embedding space.The proposed model achieves comparable results on HDFS and BGL datasets in terms of metric accuracy,recall and F1-score.Moreover,the consistent rise in F1-score proves that the representation of the embedding spacewith pre-trained embeddings is closer to the semantic information of the log. 展开更多
关键词 Anomaly detection system logs semi-structured data pre-trained embedding cascaded transformer
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A Recursive High Payload Reversible Data Hiding Using Integer Wavelet and Arnold Transform
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作者 Amishi Mahesh Kapadia P.Nithyanandam 《Intelligent Automation & Soft Computing》 SCIE 2023年第1期537-552,共16页
Reversible data hiding is an information hiding technique that requires the retrieval of the error free cover image after the extraction of the secret image.We suggested a technique in this research that uses a recurs... Reversible data hiding is an information hiding technique that requires the retrieval of the error free cover image after the extraction of the secret image.We suggested a technique in this research that uses a recursive embedding method to increase capacity substantially using the Integer wavelet transform and the Arnold transform.The notion of Integer wavelet transforms is to ensure that all coefficients of the cover images are used during embedding with an increase in payload.By scrambling the cover image,Arnold transform adds security to the information that gets embedded and also allows embedding more information in each iteration.The hybrid combination of Integer wavelet transform and Arnold transform results to build a more efficient and secure system.The proposed method employs a set of keys to ensure that information cannot be decoded by an attacker.The experimental results show that it aids in the development of a more secure storage system and withstand few tampering attacks The suggested technique is tested on many image formats,including medical images.Various performance metrics proves that the retrieved cover image and hidden image are both intact.This System is proven to withstand rotation attack as well. 展开更多
关键词 Reversible data hiding(RDH) integer wavelet transforms(IWT) arnold transform PAYLOAD embedding and extraction
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Fault Diagnosis of Power Transformer Based on Improved ACGAN Under Imbalanced Data
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作者 Tusongjiang.Kari Lin Du +3 位作者 Aisikaer.Rouzi Xiaojing Ma Zhichao Liu Bo Li 《Computers, Materials & Continua》 SCIE EI 2023年第5期4573-4592,共20页
The imbalance of dissolved gas analysis(DGA)data will lead to over-fitting,weak generalization and poor recognition performance for fault diagnosis models based on deep learning.To handle this problem,a novel transfor... The imbalance of dissolved gas analysis(DGA)data will lead to over-fitting,weak generalization and poor recognition performance for fault diagnosis models based on deep learning.To handle this problem,a novel transformer fault diagnosis method based on improved auxiliary classifier generative adversarial network(ACGAN)under imbalanced data is proposed in this paper,which meets both the requirements of balancing DGA data and supplying accurate diagnosis results.The generator combines one-dimensional convolutional neural networks(1D-CNN)and long short-term memories(LSTM),which can deeply extract the features from DGA samples and be greatly beneficial to ACGAN’s data balancing and fault diagnosis.The discriminator adopts multilayer perceptron networks(MLP),which prevents the discriminator from losing important features of DGA data when the network is too complex and the number of layers is too large.The experimental results suggest that the presented approach can effectively improve the adverse effects of DGA data imbalance on the deep learning models,enhance fault diagnosis performance and supply desirable diagnosis accuracy up to 99.46%.Furthermore,the comparison results indicate the fault diagnosis performance of the proposed approach is superior to that of other conventional methods.Therefore,the method presented in this study has excellent and reliable fault diagnosis performance for various unbalanced datasets.In addition,the proposed approach can also solve the problems of insufficient and imbalanced fault data in other practical application fields. 展开更多
关键词 Power transformer dissolved gas analysis imbalanced data auxiliary classifier generative adversarial network
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基于Vision Transformer的小麦病害图像识别算法
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作者 白玉鹏 冯毅琨 +3 位作者 李国厚 赵明富 周浩宇 侯志松 《中国农机化学报》 北大核心 2024年第2期267-274,共8页
小麦白粉病、赤霉病和锈病是危害小麦产量的三大病害。为提高小麦病害图像的识别准确率,构建一种基于Vision Transformer的小麦病害图像识别算法。首先,通过田间拍摄的方式收集包含小麦白粉病、赤霉病和锈病3种病害在内的小麦病害图像,... 小麦白粉病、赤霉病和锈病是危害小麦产量的三大病害。为提高小麦病害图像的识别准确率,构建一种基于Vision Transformer的小麦病害图像识别算法。首先,通过田间拍摄的方式收集包含小麦白粉病、赤霉病和锈病3种病害在内的小麦病害图像,并对原始图像进行预处理,建立小麦病害图像识别数据集;然后,基于改进的Vision Transformer构建小麦病害图像识别算法,分析不同迁移学习方式和数据增强对模型识别效果的影响。试验可知,全参数迁移学习和数据增强能明显提高Vision Transformer模型的收敛速度和识别精度。最后,在相同时间条件下,对比Vision Transformer、AlexNet和VGG16算法在相同数据集上的表现。试验结果表明,Vision Transformer模型对3种小麦病害图像的平均识别准确率为96.81%,相较于AlexNet和VGG16模型识别准确率分别提高6.68%和4.94%。 展开更多
关键词 小麦病害 Vision transformer 迁移学习 图像识别 数据增强
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基于Transformer的城市三角网格语义分割方法
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作者 资文杰 贾庆仁 +2 位作者 陈浩 李军 景宁 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期18-25,共8页
对城市三角网格(Urban Triangle Mesh)数据进行语义分割以识别不同类别的物体,是理解和分析三维城市场景的一种非常重要的方法.城市三角网格是一种具有丰富空间拓扑关系的三维空间几何数据,包含大量的几何信息,然而,现有的方法仅仅单独... 对城市三角网格(Urban Triangle Mesh)数据进行语义分割以识别不同类别的物体,是理解和分析三维城市场景的一种非常重要的方法.城市三角网格是一种具有丰富空间拓扑关系的三维空间几何数据,包含大量的几何信息,然而,现有的方法仅仅单独对每种几何信息进行特征提取,然后简单地融合再进行语义分割,难以利用几何信息之间的关联性,对个别物体的分割性能不佳.为了解决上述问题,提出一种基于自注意力机制Transformer的模型UMeT(Urban Mesh Transformer),其由多层感知机和MeshiT(Mesh in Transformer)模块构成,不仅可以利用多层感知机提取高维特征,还可以利用MeshiT模块计算各种几何信息之间的关联性,有效挖掘城市三角网格数据中隐含的关联.实验证明,UMeT能提取高维特征,同时保证城市三角网格数据的空间不变性,从而提升了语义分割的准确性. 展开更多
关键词 城市三角网格 语义分割 transformER MESH 自注意力机制
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Data Transformation for Super-totalstation Positioning System Integrated by GPS and Totalstation 被引量:2
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作者 GUO Jiming ZHANG Zhenglu LUO Nianxue HUANG Quanyi 《Geo-Spatial Information Science》 2003年第1期38-42,共5页
This paper focuses on the integration and data transformation between GPS and totalstation.It emphasizes on the way to transfer the WGS84 Cartesian coordinates to the local two_dimensional plane coordinates and the or... This paper focuses on the integration and data transformation between GPS and totalstation.It emphasizes on the way to transfer the WGS84 Cartesian coordinates to the local two_dimensional plane coordinates and the orthometric height GPS receiver,totalstation,radio,notebook computer and the corresponding software work together to form a new surveying system,the super_totalstation positioning system(SPS) and a new surveying model for terrestrial surveying.With the help of this system,the positions of detail points can be measured. 展开更多
关键词 全球定位系统 GPS TPS SPS 数据转换 陆地测量 测量模型
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Performance of Continuous Wavelet Transform over Fourier Transform in Features Resolutions
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作者 Michael K. Appiah Sylvester K. Danuor Alfred K. Bienibuor 《International Journal of Geosciences》 CAS 2024年第2期87-105,共19页
This study presents a comparative analysis of two image enhancement techniques, Continuous Wavelet Transform (CWT) and Fast Fourier Transform (FFT), in the context of improving the clarity of high-quality 3D seismic d... This study presents a comparative analysis of two image enhancement techniques, Continuous Wavelet Transform (CWT) and Fast Fourier Transform (FFT), in the context of improving the clarity of high-quality 3D seismic data obtained from the Tano Basin in West Africa, Ghana. The research focuses on a comparative analysis of image clarity in seismic attribute analysis to facilitate the identification of reservoir features within the subsurface structures. The findings of the study indicate that CWT has a significant advantage over FFT in terms of image quality and identifying subsurface structures. The results demonstrate the superior performance of CWT in providing a better representation, making it more effective for seismic attribute analysis. The study highlights the importance of choosing the appropriate image enhancement technique based on the specific application needs and the broader context of the study. While CWT provides high-quality images and superior performance in identifying subsurface structures, the selection between these methods should be made judiciously, taking into account the objectives of the study and the characteristics of the signals being analyzed. The research provides valuable insights into the decision-making process for selecting image enhancement techniques in seismic data analysis, helping researchers and practitioners make informed choices that cater to the unique requirements of their studies. Ultimately, this study contributes to the advancement of the field of subsurface imaging and geological feature identification. 展开更多
关键词 Continuous Wavelet transform (CWT) Fast Fourier transform (FFT) Reservoir Characterization Tano Basin Seismic data Spectral Decomposition
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基于随机增强Swin-Tiny Transformer的玉米病害识别及应用
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作者 吴叶辉 李汝嘉 +4 位作者 季荣彪 李亚东 孙晓海 陈娇娇 杨建平 《吉林大学学报(理学版)》 CAS 北大核心 2024年第2期381-390,共10页
针对图像识别中获取全局特征的局限性及难以提升识别准确性的问题,提出一种基于随机增强Swin-Tiny Transformer轻量级模型的图像识别方法.该方法在预处理阶段结合基于随机数据增强(random data augmentation based enhancement,RDABE)... 针对图像识别中获取全局特征的局限性及难以提升识别准确性的问题,提出一种基于随机增强Swin-Tiny Transformer轻量级模型的图像识别方法.该方法在预处理阶段结合基于随机数据增强(random data augmentation based enhancement,RDABE)算法对图像特征进行增强,并采用Transformer的自注意力机制,以获得更全面的高层视觉语义信息.通过在玉米病害数据集上优化Swin-Tiny Transformer模型并进行参数微调,在农业领域的玉米病害上验证了该算法的适用性,实现了更精确的病害检测.实验结果表明,基于随机增强的轻量级Swin-Tiny+RDABE模型对玉米病害图像识别准确率达93.5867%.在参数权重一致,与性能优秀的轻量级Transformer、卷积神经网络(CNN)系列模型对比的实验结果表明,改进的模型准确率比Swin-Tiny Transformer,Deit3_Small,Vit_Small,Mobilenet_V3_Small,ShufflenetV2和Efficientnet_B1_Pruned模型提高了1.1877%~4.9881%,且能迅速收敛. 展开更多
关键词 Swin-Tiny transformer模型 数据增强 迁移学习 玉米病害识别 图像分类
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Designing and Implementing an Advanced Big Data Governance Platform
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作者 Yekun Chen Tianqi Xu Yongjiang Xue 《Journal of Electronic Research and Application》 2024年第3期13-19,共7页
Contemporary mainstream big data governance platforms are built atop the big data ecosystem components,offering a one-stop development and analysis governance platform for the collection,transmission,storage,cleansing... Contemporary mainstream big data governance platforms are built atop the big data ecosystem components,offering a one-stop development and analysis governance platform for the collection,transmission,storage,cleansing,transformation,querying and analysis,data development,publishing,and subscription,sharing and exchange,management,and services of massive data.These platforms serve various role members who have internal and external data needs.However,in the era of big data,the rapid update and iteration of big data technologies,the diversification of data businesses,and the exponential growth of data present more challenges and uncertainties to the construction of big data governance platforms.This paper discusses how to effectively build a data governance platform under the big data system from the perspectives of functional architecture,logical architecture,data architecture,and functional design. 展开更多
关键词 Big data data governance Cleansing and transformation data development Sharing and exchange
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基于Transformer与局部特征融合的轨道紧固件缺陷检测方法
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作者 乔彦涵 陈文 +1 位作者 邹劲柏 季国一 《铁路计算机应用》 2024年第4期18-22,共5页
为解决传统人工巡检轨道交通线路存在的效率低和有安全隐患等问题,提出一种基于Transformer与局部特征融合的轨道紧固件缺陷检测方法。构建轨道紧固件缺陷检测模型,将Transformer与局部特征模块融合,整合局部信息,进而提取轨道紧固件缺... 为解决传统人工巡检轨道交通线路存在的效率低和有安全隐患等问题,提出一种基于Transformer与局部特征融合的轨道紧固件缺陷检测方法。构建轨道紧固件缺陷检测模型,将Transformer与局部特征模块融合,整合局部信息,进而提取轨道紧固件缺陷特征;同时,采用数据增强的方法对轨道紧固件缺陷样本进行数据扩增,扩充数据集,验证所建模型的检测效果。实验结果表明,相较于传统方法,文章提出的方法在识别轨道紧固件缺失和损坏两类缺陷方面的精度和平均准确率均有所提升,在不同的轨道线路实验环境下也表现出良好的检测效果。 展开更多
关键词 轨道线路 紧固件缺陷检测 transformER 局部特征 数据增强
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Application of data warehouse in power transformer diagnosis system
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作者 ZHAO Wen-qing ZHANG Yan-fang WANG Xiao-hui 《通讯和计算机(中英文版)》 2009年第11期17-20,共4页
关键词 数据仓库技术 电力变压器 故障诊断系统 数据挖掘系统 变压器故障 应用 在线分析技术 电力公司
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基于Transformer的空调能耗预测模型构建与参数优化
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作者 刘兴成 《建筑节能(中英文)》 CAS 2024年第3期82-86,共5页
针对空调系统能耗预测建模过程中的数据质量、模型输入参数筛选等问题,研究基于Transformer神经网络的空调系统能耗预测模型构建和参数优化方法,结果表明:可以通过广义极端学生化偏差方法对数据中的离群值进行检测修正,从而提升数据质量... 针对空调系统能耗预测建模过程中的数据质量、模型输入参数筛选等问题,研究基于Transformer神经网络的空调系统能耗预测模型构建和参数优化方法,结果表明:可以通过广义极端学生化偏差方法对数据中的离群值进行检测修正,从而提升数据质量;通过余弦相似度对输入参数进行两两相关性检验来消除各参数间的多重共线性,实现对输入参数的初步筛选;采用随机森林算法计算初选参数对空调能耗预测结果的影响来判断冗余参数,进而完成对输入特征参数的最终筛选;建立的空调能耗预测模型对数据测试集的预测结果均方根误差RMSE为38.831 kW,相关系数R^(2)为0.952,表现出了良好的预测性能。 展开更多
关键词 空调系统能耗预测 transformer神经网络 数据质量 模型参数优化
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嵌入局部聚类描述符的视频问答Transformer模型 被引量:1
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作者 郭丹 姚沈涛 +1 位作者 王辉 汪萌 《计算机学报》 EI CAS CSCD 北大核心 2023年第4期671-689,共19页
视频问答(Video Question Answering)是典型的跨模态理解任务,其目的是根据提问的文本对视频内容进行理解并推理正确的答案,如何有效地对多模态输入进行特征表示并建立跨模态间复杂的语义关联是解决这一任务的关键难点.为了正确地推理结... 视频问答(Video Question Answering)是典型的跨模态理解任务,其目的是根据提问的文本对视频内容进行理解并推理正确的答案,如何有效地对多模态输入进行特征表示并建立跨模态间复杂的语义关联是解决这一任务的关键难点.为了正确地推理结果,模型首先必须捕获视频序列和复杂文本中包含的关键语义信息.本文提出了一种嵌入局部聚类描述符的视频问答Transformer模型,称为TVLAD-Net(Transformer Residual-less VLAD Network).TVLAD-Net主要包含一个端到端可训练的无残差局部聚合描述符模块(RVLAD,Residual-less Vec⁃tor of Local Aggregated Descriptor),以及一个统一的语义转换模块(Transformer).具体来说,RVLAD通过设置多个不同的聚类中心将视频和文本特征分别聚合为少量紧凑的局部聚类描述符;每个聚类描述符从全局角度分配及汇总了序列上权重不一的语义信息,相比于聚合前的视频帧特征或文本词特征具有更丰富的表征能力.Trans⁃former模块能够利用模态间的相互语义引导,实现多模态聚类描述符的语义交互,即采用多头注意力机制同时求解模态内和模态间的语义关联,进而避免了与所求解问题无关或者冗余的描述符语义单元的聚合.实验评估在TGIF-QA、MSVD-QA和MSRVTT-QA三个基准数据集上进行;实验结果表明本文方法能够实现先进的问答推理,在整体的评价指标上与现有方法相比有2%~5%的性能提升. 展开更多
关键词 视频问答 多模态数据 聚类描述符 自注意力变换网络 深度学习
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逐层Transformer在类别不均衡数据的应用
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作者 杨晶东 李熠伟 +3 位作者 江彪 姜泉 韩曼 宋梦歌 《计算机应用研究》 CSCD 北大核心 2023年第10期3047-3052,共6页
为解决临床医学量表数据类别不均衡容易对模型产生影响,以及在处理量表数据任务时深度学习框架性能难以媲美传统机器学习方法问题,提出了一种基于级联欠采样的Transformer网络模型(layer by layer Transformer,LLT)。LLT通过级联欠采样... 为解决临床医学量表数据类别不均衡容易对模型产生影响,以及在处理量表数据任务时深度学习框架性能难以媲美传统机器学习方法问题,提出了一种基于级联欠采样的Transformer网络模型(layer by layer Transformer,LLT)。LLT通过级联欠采样方法对多数类数据逐层删减,实现数据类别平衡,降低数据类别不均衡对分类器的影响,并利用注意力机制对输入数据的特征进行相关性评估实现特征选择,细化特征提取能力,改善模型性能。采用类风湿关节炎(RA)数据作为测试样本,实验证明,在不改变样本分布的情况下,提出的级联欠采样方法对少数类别的识别率增加了6.1%,与常用的NEARMISS和ADASYN相比,分别高出1.4%和10.4%;LLT在RA量表数据的准确率和F 1-score指标上达到了72.6%和71.5%,AUC值为0.89,mAP值为0.79,性能超过目前RF、XGBoost和GBDT等主流量表数据分类模型。最后对模型过程进行可视化,分析了影响RA的特征,对RA临床诊断具有较好的指导意义。 展开更多
关键词 量表数据分类 类别不均衡 级联欠采样 transformER
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