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Examining heterogeneity of stromal cells in tumor microenvironment based on pan-cancer single-cell RNA sequencing data
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作者 Wenhui Wang Li Wang +1 位作者 Junjun She Jun Zhu 《Cancer Biology & Medicine》 SCIE CAS CSCD 2022年第1期30-42,共13页
Tumor tissues contain both tumor and non-tumor cells,which include infiltrated immune cells and stromal cells,collectively called the tumor microenvironment(TME).Single-cell RNA sequencing(sc RNAseq)enables the examin... Tumor tissues contain both tumor and non-tumor cells,which include infiltrated immune cells and stromal cells,collectively called the tumor microenvironment(TME).Single-cell RNA sequencing(sc RNAseq)enables the examination of heterogeneity of tumor cells and TME.In this review,we examined sc RNAseq datasets for multiple cancer types and evaluated the heterogeneity of major cell type composition in different cancer types.We further showed that endothelial cells and fibroblasts/myofibroblasts in different cancer types can be classified into common subtypes,and the subtype composition is clearly associated with cancer characteristic and therapy response. 展开更多
关键词 Stromal cells tumor microenvironment pan-cancer single-cell RNA sequencing data
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A Comparative Study of Data Representation Techniques for Deep Learning-Based Classification of Promoter and Histone-Associated DNA Regions
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作者 Sarab Almuhaideb Najwa Altwaijry +2 位作者 Isra Al-Turaiki Ahmad Raza Khan Hamza Ali Rizvi 《Computers, Materials & Continua》 2025年第11期3095-3128,共34页
Many bioinformatics applications require determining the class of a newly sequenced Deoxyribonucleic acid(DNA)sequence,making DNA sequence classification an integral step in performing bioinformatics analysis,where la... Many bioinformatics applications require determining the class of a newly sequenced Deoxyribonucleic acid(DNA)sequence,making DNA sequence classification an integral step in performing bioinformatics analysis,where large biomedical datasets are transformed into valuable knowledge.Existing methods rely on a feature extraction step and suffer from high computational time requirements.In contrast,newer approaches leveraging deep learning have shown significant promise in enhancing accuracy and efficiency.In this paper,we investigate the performance of various deep learning architectures:Convolutional Neural Network(CNN),CNN-Long Short-Term Memory(CNNLSTM),CNN-Bidirectional Long Short-Term Memory(CNN-BiLSTM),Residual Network(ResNet),and InceptionV3 for DNA sequence classification.Various numerical and visual data representation techniques are utilized to represent the input datasets,including:label encoding,k-mer sentence encoding,k-mer one-hot vector,Frequency Chaos Game Representation(FCGR)and 5-Color Map(ColorSquare).Three datasets are used for the training of the models including H3,H4 and DNA Sequence Dataset(Yeast,Human,Arabidopsis Thaliana).Experiments are performed to determine which combination of DNA representation and deep learning architecture yields improved performance for the classification task.Our results indicate that using a hybrid CNN-LSTM neural network trained on DNA sequences represented as one-hot encoded k-mer sequences yields the best performance,achieving an accuracy of 92.1%. 展开更多
关键词 DNA sequence classification deep learning data visualization
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High-throughput Sequencing Technology and Its Application 被引量:11
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作者 Zhu Qiang-long Liu Shi +1 位作者 Gao Peng Luan Fei-shi 《Journal of Northeast Agricultural University(English Edition)》 CAS 2014年第3期84-96,共13页
Gene sequencing is a great way to interpret life, and high-throughput sequencing technology is a revolutionary technological innovation in gene sequencing researches. This technology is characterized by low cost and h... Gene sequencing is a great way to interpret life, and high-throughput sequencing technology is a revolutionary technological innovation in gene sequencing researches. This technology is characterized by low cost and high-throughput data. Currently, high-throughput sequencing technology has been widely applied in multi-level researches on genomics, transcriptomics and epigenomics. And it has fundamentally changed the way we approach problems in basic and translational researches and created many new possibilities. This paper presented a general description of high-throughput sequencing technology and a comprehensive review of its application with plain, concisely and precisely. In order to help researchers finish their work faster and better, promote science amateurs and understand it easier and better. 展开更多
关键词 high-throughput sequencing data analysis genome sequence transcriptome sequence BIOINFORMATICS
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Breed identification using breed‑informative SNPs and machine learning based on whole genome sequence data and SNP chip data 被引量:4
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作者 Changheng Zhao Dan Wang +4 位作者 Jun Teng Cheng Yang Xinyi Zhang Xianming Wei Qin Zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第5期1941-1953,共13页
Background Breed identification is useful in a variety of biological contexts.Breed identification usually involves two stages,i.e.,detection of breed-informative SNPs and breed assignment.For both stages,there are se... Background Breed identification is useful in a variety of biological contexts.Breed identification usually involves two stages,i.e.,detection of breed-informative SNPs and breed assignment.For both stages,there are several methods proposed.However,what is the optimal combination of these methods remain unclear.In this study,using the whole genome sequence data available for 13 cattle breeds from Run 8 of the 1,000 Bull Genomes Project,we compared the combinations of three methods(Delta,FST,and In)for breed-informative SNP detection and five machine learning methods(KNN,SVM,RF,NB,and ANN)for breed assignment with respect to different reference population sizes and difference numbers of most breed-informative SNPs.In addition,we evaluated the accuracy of breed identification using SNP chip data of different densities.Results We found that all combinations performed quite well with identification accuracies over 95%in all scenarios.However,there was no combination which performed the best and robust across all scenarios.We proposed to inte-grate the three breed-informative detection methods,named DFI,and integrate the three machine learning methods,KNN,SVM,and RF,named KSR.We found that the combination of these two integrated methods outperformed the other combinations with accuracies over 99%in most cases and was very robust in all scenarios.The accuracies from using SNP chip data were only slightly lower than that from using sequence data in most cases.Conclusions The current study showed that the combination of DFI and KSR was the optimal strategy.Using sequence data resulted in higher accuracies than using chip data in most cases.However,the differences were gener-ally small.In view of the cost of genotyping,using chip data is also a good option for breed identification. 展开更多
关键词 Breed identification Breed-informative SNPs Genomic breed composition Machine learning Whole genome sequence data
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Incorporating genomic annotation into single-step genomic prediction with imputed whole-genome sequence data 被引量:2
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作者 TENG Jin-yan YE Shao-pan +8 位作者 GAO Ning CHEN Zi-tao DIAO Shu-qi LI Xiu-jin YUAN Xiao-long ZHANG Hao LI Jia-qi ZHANG Xi-quan ZHANG Zhe 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第4期1126-1136,共11页
Single-step genomic best linear unbiased prediction(ss GBLUP) is now intensively investigated and widely used in livestock breeding due to its beneficial feature of combining information from both genotyped and ungeno... Single-step genomic best linear unbiased prediction(ss GBLUP) is now intensively investigated and widely used in livestock breeding due to its beneficial feature of combining information from both genotyped and ungenotyped individuals in the single model. With the increasing accessibility of whole-genome sequence(WGS) data at the population level, more attention is being paid to the usage of WGS data in ss GBLUP. The predictive ability of ss GBLUP using WGS data might be improved by incorporating biological knowledge from public databases. Thus, we extended ss GBLUP, incorporated genomic annotation information into the model, and evaluated them using a yellow-feathered chicken population as the examples. The chicken population consisted of 1 338 birds with 23 traits, where imputed WGS data including 5 127 612 single nucleotide polymorphisms(SNPs) are available for 895 birds. Considering different combinations of annotation information and models, original ss GBLUP, haplotype-based ss GHBLUP, and four extended ss GBLUP incorporating genomic annotation models were evaluated. Based on the genomic annotation(GRCg6a) of chickens, 3 155 524 and 94 837 SNPs were mapped to genic and exonic regions, respectively. Extended ss GBLUP using genic/exonic SNPs outperformed other models with respect to predictive ability in 15 out of 23 traits, and their advantages ranged from 2.5 to 6.1% compared with original ss GBLUP. In addition, to further enhance the performance of genomic prediction with imputed WGS data, we investigated the genotyping strategies of reference population on ss GBLUP in the chicken population. Comparing two strategies of individual selection for genotyping in the reference population, the strategy of evenly selection by family(SBF) performed slightly better than random selection in most situations. Overall, we extended genomic prediction models that can comprehensively utilize WGS data and genomic annotation information in the framework of ss GBLUP, and validated the idea that properly handling the genomic annotation information and WGS data increased the predictive ability of ss GBLUP. Moreover, while using WGS data, the genotyping strategy of maximizing the expected genetic relationship between the reference and candidate population could further improve the predictive ability of ss GBLUP. The results from this study shed light on the comprehensive usage of genomic annotation information in WGS-based single-step genomic prediction. 展开更多
关键词 genomic selection prior information sequencing data genotype imputation HAPLOTYPE
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Analysis on the Influence of Automatic Station Temperature Data on the Sequence Continuity of Historical Meteorological Data 被引量:1
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作者 CHEN Ming1, GAI Xiao-bo2, FAN Xin-yu1, SONG Min1 1. Jinzhou Meteorology Bureau in Liaoning Province, Jinzhou 121001, China 2. Dalian Meteorological Bureau in Liaoning Province, Dalian 116001, China 《Meteorological and Environmental Research》 CAS 2011年第4期12-14,17,共4页
[Objective] The research aimed to study the influence of automatic station data on the sequence continuity of historical meteorological data. [Method] Based on the temperature data which were measured by the automatic... [Objective] The research aimed to study the influence of automatic station data on the sequence continuity of historical meteorological data. [Method] Based on the temperature data which were measured by the automatic meteorological station and the corresponding artificial observation data during January-December in 2001, the monthly average, maximum and minimum temperatures in the automatic station were compared with the corresponding artificial observation temperature data in the parallel observation period by using the contrast difference and the standard deviation of difference value. The difference between the automatic station and the artificial data, the variation characteristics were understood. Meanwhile, the significance test and analysis of annual average value were carried out by the data sequence during 1990-2009. The influence of automatic station replacing the artificial observation on the sequence continuity of historical temperature data was discussed. [Result] Although the two temperature data in the parallel observation period had the certain difference, the difference was in the permitted range of automatic station difference value on average. The difference of individual month surpassed the permitted range of automatic station difference value. The significance test showed that the annual average temperature and the annual average minimum temperature which were observed in the automatic station had the difference with the historical data. It had the certain influence on the annual temperature sequence, but the difference wasn’t significant as a whole. When the automatic observation combined with the artificial observation to use, the sequence needed carry out the homogeneous test and correction. [Conclusion] The research played the important role on guaranteeing the monorail running of automatic station, optimizing the meteorological surface observation system, improving the climate sequence continuity of meteorological element and the reliability of climate statistics. 展开更多
关键词 Automatic observation Artificial observation data sequence ANALYSIS China
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Surveillance of emerging SARS-CoV-2 variants by nanopore technology-based genome sequencing 被引量:1
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作者 J.I.Abeynayake G.P.Chathuranga +1 位作者 M.A.Y.Fernando M.K.Sahoo 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2023年第7期313-320,共8页
Objective:To surveill emerging variants by nanopore technology-based genome sequencing in different COVID-19 waves in Sri Lanka and to examine the association with the sample characteristics,and vaccination status.Met... Objective:To surveill emerging variants by nanopore technology-based genome sequencing in different COVID-19 waves in Sri Lanka and to examine the association with the sample characteristics,and vaccination status.Methods:The study analyzed 207 RNA positive swab samples received to sequence laboratory during different waves.The N gene cut-off threshold of less than 30 was considered as the major inclusion criteria.Viral RNA was extracted,and elutes were subjected to nanopore sequencing.All the sequencing data were uploaded in the publicly accessible database,GISAID.Results:The Omicron,Delta and Alpha variants accounted for 58%,22%and 4%of the variants throughout the period.Less than 1%were Kappa variant and 16%of the study samples remained unassigned.Omicron variant was circulated among all age groups and in all the provinces.Ct value and variants assigned percentage was 100%in Ct values of 10-15 while only 45%assigned Ct value over 25.Conclusions:The present study examined the emergence,prevalence,and distribution of SARS-CoV-2 variants locally and has shown that nanopore technology-based genome sequencing enables whole genome sequencing in a low resource setting country. 展开更多
关键词 Emerging SARS-CoV-2 variants Laboratory surveillance Nanopore technology Genome sequencing Bioinformatics analysis and phylogeny Sociodemographic and sample cutoff(Ct)threshold Global sharing of genomic data/GISAID
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Sequence detection data fusion with distributed multisensor
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作者 王祁 聂伟 孙圣和 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1999年第3期57-60,共4页
This Paper presents a data fusion method with distributed sequence detection for on hypothasis testingtheory including the data fusion algorithm of sequence detection based on least error probability rule, the decisio... This Paper presents a data fusion method with distributed sequence detection for on hypothasis testingtheory including the data fusion algorithm of sequence detection based on least error probability rule, the decision ruleand the calcation formula of the detction times and the simulation result of system performance as well. 展开更多
关键词 DISTRIBUTED sequencE detection data FUSION hypotheses TESTING THEORY
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Logging Data High-Resolution Sequence Stratigraphy
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作者 李洪奇 谢寅符 +1 位作者 孙中春 罗兴平 《Journal of China University of Geosciences》 SCIE CSCD 2006年第2期173-180,共8页
The recognition and contrast of bed sets in parasequence is difficult in terrestrial basin high-resolution sequence stratigraphy. This study puts forward new methods for the boundary identification and contrast of bed... The recognition and contrast of bed sets in parasequence is difficult in terrestrial basin high-resolution sequence stratigraphy. This study puts forward new methods for the boundary identification and contrast of bed sets on the basis of manifold logging data. The formation of calcareous interbeds, shale resistivity differences and the relation of reservoir resistivity to altitude are considered on the basis of log curve morphological characteristics, core observation, cast thin section, X-ray diffraction and scanning electron microscopy. The results show that the thickness of calcareous interbeds is between 0.5 m and 2 m, increasing on weathering crusts and faults. Calcareous interbeds occur at the bottom of a distributary channel and the top of a distributary mouth bar. Lower resistivity shale (4-5 Ω · m) and higher resistivity shale (〉 10Ω·m) reflect differences in sediment fountain or sediment microfacies. Reservoir resistivity increases with altitude. Calcareous interbeds may be a symbol of recognition for the boundary of bed sets and isochronous contrast bed sets, and shale resistivity differences may confirm the stack relation and connectivity of bed sets. Based on this, a high-resolution chronostratigraphic frame- work of Xi-1 segment in Shinan area, Junggar basin is presented, and the connectivity of bed sets and oil-water contact is confirmed. In this chronostratigraphic framework, the growth order, stack mode and space shape of bed sets are qualitatively and quantitatively described. 展开更多
关键词 Junggar basin logging data sequence stratigraphy calcareous interbeds shale resistivity relationship of resistivity to altitude reservoir connectivity.
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Clinical and ethical considerations of massively parallel sequencing in transplantation science
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作者 Andreas Scherer 《World Journal of Transplantation》 2013年第4期62-67,共6页
Massively parallel sequencing(MPS), alias next-generation sequencing, is making its way from research laboratories into applied sciences and clinics. MPS is a framework of experimental procedures which offer possibili... Massively parallel sequencing(MPS), alias next-generation sequencing, is making its way from research laboratories into applied sciences and clinics. MPS is a framework of experimental procedures which offer possibilities for genome research and genetics which could only be dreamed of until around 2005 when these technologies became available. Sequencing of a transcriptome, exome, even entire genomes is now possible within a time frame and precision that we could only hope for 10 years ago. Linking other experimental procedures with MPS enables researchers to study secondary DNA modifications across the entire genome, and protein binding sites, to name a few applications. How the advancements of sequencing technologies can contribute to transplantation science is subject of this discussion: immediate applications are in graft matching via human leukocyte antigen sequencing, as part of systems biology approaches which shed light on gene expression processes during immune response, as biomarkers of graft rejection, and to explore changes of microbiomes as a result of transplantation. Of considerable importance is the socio-ethical aspect of data ownership, privacy, informed consent, and result report to the study participant. While the technology is advancing rapidly, legislation is lagging behind due to the globalisation of data requisition, banking and sharing. 展开更多
关键词 sequencing DIAGNOSIS ETHICS Consent data management
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Next generation sequencing for profiling expression of miRNAs: technical progress and applications in drug development
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作者 Jie Liu Steven F. Jennings +1 位作者 Weida Tong Huixiao Hong 《Journal of Biomedical Science and Engineering》 2011年第10期666-676,共11页
miRNAs are non-coding RNAs that play a regulatory role in expression of genes and are associated with diseases. Quantitatively measuring expression levels of miRNAs can help understanding the mechanisms of human disea... miRNAs are non-coding RNAs that play a regulatory role in expression of genes and are associated with diseases. Quantitatively measuring expression levels of miRNAs can help understanding the mechanisms of human diseases and discovering new drug targets. There are three major methods that have been used to measure the expression levels of miRNAs: real-time reverse transcription PCR (qRT-PCR), microarray, and the newly introduced next-generation sequencing (NGS). NGS is not only suitable for profiling of known miRNAs that qRT-PCR and microarray can do too but also able to detect unknown miRNAs that the other two methods are incapable. Profiling of miRNAs by NGS has been progressed rapidly and is a promising field for applications in drug development. This paper will review the technical advancement of NGS for profiling miRNAs, including comparative analyses between different platforms and software packages for analyzing NGS data. Examples and future perspectives of applications of NGS profiling miRNAs in drug development will be discussed. 展开更多
关键词 MIRNAS Next-Generation sequencing EXPRESSION data Analysis Drug Development
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DISCUSSION ON AVERAGE GENERATION OF TWODIMENSIONAL DATA SEQUENCE IN GREY SYSTEM THEORY
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作者 PINGXue-liang ZHOURu-rong LIUSheng-lan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第4期298-303,共6页
An unequal time interval sequence or a sequence with blanks is usually completed with average generation in grey system theory. This paper discovers that there exists obvious errors when using average generation to ge... An unequal time interval sequence or a sequence with blanks is usually completed with average generation in grey system theory. This paper discovers that there exists obvious errors when using average generation to generate internal points of non-consecutive neighbours. The average generation and the preference generation of the sequence are discussed, the concave and convex properties show the status of local sequence and propose a new idea for using the status to build up the criteria of choosing generation coefficient. Compared with the general average method of the one-dimensional data sequence, the two-dimensional data sequence is defined and its average generation is discussed, and the coefficient decision method for the preference generation is presented. 展开更多
关键词 average generation grey system theory data sequence non-consecutive neighbors
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Sequence-To-Sequence Learning for Online Imputation of Sensory Data
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作者 Kaitai TONG Teng LI 《Instrumentation》 2019年第2期63-70,共8页
Online sensing can provide useful information in monitoring applications,for example,machine health monitoring,structural condition monitoring,environmental monitoring,and many more.Missing data is generally a signifi... Online sensing can provide useful information in monitoring applications,for example,machine health monitoring,structural condition monitoring,environmental monitoring,and many more.Missing data is generally a significant issue in the sensory data that is collected online by sensing systems,which may affect the goals of monitoring programs.In this paper,a sequence-to-sequence learning model based on a recurrent neural network(RNN)architecture is presented.In the proposed method,multivariate time series of the monitored parameters is embedded into the neural network through layer-by-layer encoders where the hidden features of the inputs are adaptively extracted.Afterwards,predictions of the missing data are generated by network decoders,which are one-step-ahead predictive data sequences of the monitored parameters.The prediction performance of the proposed model is validated based on a real-world sensory dataset.The experimental results demonstrate the performance of the proposed RNN-encoder-decoder model with its capability in sequence-to-sequence learning for online imputation of sensory data. 展开更多
关键词 data IMPUTATION RECURRENT NEURAL Network sequence-To-sequence Learning sequencE Prediction
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Next-generation sequencing for clinical HLA typing
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作者 Chengyu Wu Qiang Shi +1 位作者 Dinh Pham Afzal Nikaein 《实用器官移植电子杂志》 2018年第4期275-285,共11页
下一代测序(NGS)已经被证明可有效的减少人类白细胞抗原(HLA)分型的不准确性和检测成本,同时还可以检测出之前未测序的HLA基因的详细信息。本研究介绍了在Illumina公司的Mi Seq平台上使用NGS开发的HLA分型测定的性能要求。共纳入288个样... 下一代测序(NGS)已经被证明可有效的减少人类白细胞抗原(HLA)分型的不准确性和检测成本,同时还可以检测出之前未测序的HLA基因的详细信息。本研究介绍了在Illumina公司的Mi Seq平台上使用NGS开发的HLA分型测定的性能要求。共纳入288个样品,其之前以HLA-A,HLA-B,HLA-C,HLA-DRB1,HLA-DQA/B和HLA-DPA/B为特征,其使用Sanger测序、序列特异性引物和序列特异性寡核苷酸技术进行高分辨率的分型。这些样本携带高比例HLA特异性的等位基因。测序数据使用Omixon的HLA TwinTM进行分析。评估等位基因平衡、敏感性、特异性、精确性、准确性和不准确性。这些结果证明了NGS对HLA分型的可行性和获益处,因为这项技术非常准确,几乎排除了所有的不确定性,为HLA基因长度提供了完整的测序信息,并形成了利用单一方法进行HLA分型的基础免疫遗传学实验室。 展开更多
关键词 HLA分型 下一代测序 全基因组Illumina数据分析 临床应用
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基于个性化数据增强的自监督序列推荐算法 被引量:1
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作者 王帅 史艳翠 《计算机工程》 北大核心 2025年第8期190-202,共13页
序列推荐算法通过对用户的历史行为进行动态建模,以预测其可能感兴趣的内容。聚焦对比式自监督学习(SSL)在序列推荐中的应用,通过设计有效的自监督信号,增强模型在稀疏数据场景下的表征能力。首先,针对随机数据增强易引入数据噪声的问题... 序列推荐算法通过对用户的历史行为进行动态建模,以预测其可能感兴趣的内容。聚焦对比式自监督学习(SSL)在序列推荐中的应用,通过设计有效的自监督信号,增强模型在稀疏数据场景下的表征能力。首先,针对随机数据增强易引入数据噪声的问题,提出融合用户偏好的个性化数据增强方法,通过用户评分引导增强过程,同时对长、短序列使用不同的增强方法组合,生成符合用户偏好的增强序列;其次,为了缓解训练中出现的数据特征学习不平衡问题,设计一种混合增强训练法,在训练前期,通过随机选择增强方法生成增强序列,提高模型的性能和泛化能力,在训练后期,选择与原始序列相似度较高的增强序列,使模型全面学习用户的实际偏好和行为模式;最后,将传统的序列预测目标与SSL目标相结合,推断出用户的表示。在数据集Beauty、Toys和Sports上进行实验验证,结果表明,相较于基线模型中的最优结果,所提方法的HR@5指标分别提升了6.61%、3.11%和3.76%,NDCG@5指标分别提升了11.40%、3.50%和2.16%,上述实验结果验证了该方法的合理性和有效性。 展开更多
关键词 序列推荐 自监督学习 数据增强 推荐系统 数据特征
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基于栅格细化的露天矿区路网模型快速构建方法
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作者 顾清华 胡俸源 +3 位作者 王倩 柴小博 王丹 井欣欣 《煤炭学报》 北大核心 2025年第S1期645-654,共10页
露天矿区路网构建是实现露天矿卡车智能调度和无人驾驶的重要前提,但由于露天矿区道路较为复杂,矿车GPS轨迹数据采集量大,冗余数据和异常点繁多,构建路网模型仍存在较多难点。为解决此问题,提出一种基于栅格细化的露天矿区路网模型快速... 露天矿区路网构建是实现露天矿卡车智能调度和无人驾驶的重要前提,但由于露天矿区道路较为复杂,矿车GPS轨迹数据采集量大,冗余数据和异常点繁多,构建路网模型仍存在较多难点。为解决此问题,提出一种基于栅格细化的露天矿区路网模型快速构建方法。首先提出基于改进膨胀算法的栅格去噪方法,对轨迹点二值化生成的路网栅格进行清洗,使用改进膨胀算法对低连通度的栅格空缺进行填充,减少栅格离散和断裂的影响;然后构建基于改进Zhang-Suen细化算法的路网骨架提取模型,对栅格区域进行图像形态学特征识别,利用改进Zhang-Suen细化算法提取栅格骨架图,使得提取的栅格骨架宽度恒定为一个栅格,减少原始细化算法处理后的毛刺和冗余;之后利用轨迹的时序特性,设计基于轨迹时序的路网骨架连接算法,提取路网的实际通行道路,解决因栅格化方法导致的路网异常连通的问题,并获得更好的道路连通效果;最后,根据实际应用需求和路网道路结构构建实际的路网模型,提出点-路-点的路网模型结构,在保证路网逻辑结构不变的情况下大幅减少路网的复杂程度和计算规模,并使用folium对路网进行可视化处理。实验表明:该方法构建的路网准确性、完整性分别为95.45%、96.43%;程序运行时间为2.697 s,满足露天矿路网模型生成快、精度高的使用需求。 展开更多
关键词 露天矿 轨迹数据 二值化 Zhang-Suen细化算法 轨迹顺序
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引入迷思概念的关键行动编码及其在过程数据诊断分类分析中的应用
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作者 詹沛达 高方方 陈琦鹏 《心理科学》 北大核心 2025年第2期485-503,共19页
迷思概念是指基于个人经验构建地对一些对象、事件或观点的错误理解,额外识别迷思概念有助于明确学生出现错误的具体原因。引入迷思概念的关键行动编码可实现基于过程数据对问题解决技能和迷思概念的联合诊断。通过实证例子阐述新编码... 迷思概念是指基于个人经验构建地对一些对象、事件或观点的错误理解,额外识别迷思概念有助于明确学生出现错误的具体原因。引入迷思概念的关键行动编码可实现基于过程数据对问题解决技能和迷思概念的联合诊断。通过实证例子阐述新编码方式在过程数据诊断分类分析中的应用与表现。结果发现:(1)引入迷思概念可实现对参与者的更精细分类,提供包含问题解决技能和迷思概念的综合诊断反馈;(2)迷思概念的掌握程度与任务最终表现呈中到高程度负相关。总之,新编码方式有助于研究者在过程数据分析中额外利用导致错误结果的问题解决过程所包含的信息,有助于更全面识别导致问题解决成败的具体原因,有益于实施有针对性干预。 展开更多
关键词 认知诊断 过程数据 问题解决 迷思概念 行动序列
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基于MapReduce的拷贝数变异测序数据并行处理方案
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作者 何亨 程凯莉 +1 位作者 张葵 成淑君 《计算机工程》 北大核心 2025年第5期177-187,共11页
拷贝数变异(CNV)作为一种遗传变异,广泛存在于人类基因组的基因分布中。CNV检测效率的提升不仅可以为更多的病患提供更加快速精确的CNV检测结果,大幅降低医疗成本,同时又有利于药物的研发和临床应用。基于读段深度(RD)的方法是目前最为... 拷贝数变异(CNV)作为一种遗传变异,广泛存在于人类基因组的基因分布中。CNV检测效率的提升不仅可以为更多的病患提供更加快速精确的CNV检测结果,大幅降低医疗成本,同时又有利于药物的研发和临床应用。基于读段深度(RD)的方法是目前最为常用的CNV检测方法,对RD相关信息的处理时间较长,在CNV检测中时间占比较高。现有方法无法有效应用于全基因组分析,存在计算效率较低、检测精度下降的问题。基于RD的CNV检测方法,提出一种高效的测序数据并行处理方案EPPCNV。在EPPCNV中,设计2个MapReduce作业串行执行的方法,实现高效全基因组测序数据的并行处理,精准地完成RD相关信息的提取;为充分考虑到GC含量偏差对CNV检测结果的影响,对测序数据的RDs进行校正处理,保证最终检测结果的高灵敏度与高精确度;采用独立于具体CNV检测方法的高适配性数据处理方式,其最终生成的RD相关信息能够与多种主流CNV检测方法直接结合,在不改变原方法对CNV区域判定的基础上,实现方法整体性能的大幅提升。实验结果表明,EPPCNV的综合准确率高,分别与CNV-LOF、HBOS-CNV以及CNVnator 3种方法直接结合,能够显著提升原方法的计算效率,并保证检测结果的高灵敏度与高精确度。对于覆盖深度越高、数据量越大的测序数据,CNV检测方法与EPPCNV结合后计算效率的提升更为显著。 展开更多
关键词 拷贝数变异检测 MapReduce作业 测序数据处理 读段深度 全基因组
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基于误差序列的离线数据无监督快速异常检测方法研究
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作者 谷阳阳 张东 《计算机测量与控制》 2025年第11期111-117,共7页
针对利用多维度、多模态的遥测参量实现快速定位检测故障需求的问题,在分析和归纳飞行器遥测参量特点及故障检测方法的基础上,研究了基于误差序列的离线数据无监督快速异常检测方法;该方法改变了传统的主要依靠人工分析进行故障判定模式... 针对利用多维度、多模态的遥测参量实现快速定位检测故障需求的问题,在分析和归纳飞行器遥测参量特点及故障检测方法的基础上,研究了基于误差序列的离线数据无监督快速异常检测方法;该方法改变了传统的主要依靠人工分析进行故障判定模式,结合历史数据的使用,通过无监督自适应阈值的设定,实现自动适配并检测遥测参量异常记录状态的功能,降低了需要大量人员分析的时间成本,减少了遂行处理工作中快速定位故障的压力,解决了故障定位通用性不强的问题;经过实际应用,效果良好,满足数据处理要求,具有较好的自适应性,易于实现。 展开更多
关键词 遥测数据处理 自适应阈值 误差序列 自动检测 数据驱动方法
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基于PBL-BPNN算法和多源数据的住区更新敏感度研究
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作者 朱隆斌 赵瑞寅 《地球信息科学学报》 北大核心 2025年第9期2039-2051,共13页
【目的】国家“十四五”规划明确提出实施城市更新行动,特别是以老旧小区为载体的住区更新。但现有的住区更新实践仍缺乏对更新时序的统筹安排与操作指导。【方法】运用PBL-BPNN算法和多源数据构建评价方法和指标体系,并将住区更新敏感... 【目的】国家“十四五”规划明确提出实施城市更新行动,特别是以老旧小区为载体的住区更新。但现有的住区更新实践仍缺乏对更新时序的统筹安排与操作指导。【方法】运用PBL-BPNN算法和多源数据构建评价方法和指标体系,并将住区更新敏感度作为更新可能性的度量值量化更新时序的研究内容。该方法综合考虑住区建成环境、人口分布等多重指标,通过对已更新住区的特征提取,实现更新时序的大规模量化分析。【结果】对比传统评价指标模型和加入多源数据后的模型发现,后者在验证集上10折交叉验证的RMSE为0.142 2,F-score为0.750 9,在测试集上的准确度提升了32.78%,证明了该方法和评价指标的有效性。实证分析发现,南京中心城区的住区更新敏感度呈现“内部高,外部低,多点散布”的空间格局;同时,多源数据中的商业资源、公共空间资源、工作日人数、围合度、丰富度和宜人感6条指标对住区更新敏感度的评价产生较大影响。【结论】该方法运用数据挖掘思想和机器学习技术,突破了传统更新时序评价方法中主观性较强的局限,可作为住区更新规划和实施的决策依据,并为住区更新的时序判断提供技术方法支持。 展开更多
关键词 城市更新 更新时序 住区更新 更新敏感度 机器学习 多源数据 街景图像 南京中心城区
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