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基于改进Sequence-to-Sequence模型的文本摘要生成方法 被引量:13
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作者 周健 田萱 崔晓晖 《计算机工程与应用》 CSCD 北大核心 2019年第1期128-134,共7页
基于循环神经网络和注意力机制的Sequence-to-Sequence模型神经网络方法在信息抽取和自动摘要生成方面发挥了重要作用。然而,该方法不能充分利用文本的语言特征信息,且生成结果中存在未登录词问题,从而影响文本摘要的准确性和可读性。为... 基于循环神经网络和注意力机制的Sequence-to-Sequence模型神经网络方法在信息抽取和自动摘要生成方面发挥了重要作用。然而,该方法不能充分利用文本的语言特征信息,且生成结果中存在未登录词问题,从而影响文本摘要的准确性和可读性。为此,利用文本语言特征改善输入的特性,同时引入拷贝机制缓解摘要生成过程未登录词问题。在此基础上,提出基于Sequence-to-Sequence模型的新方法 Copy-Generator模型,以提升文本摘要生成效果。采用中文摘要数据集LCSTS为数据源进行实验,结果表明所提方法能够有效地提高生成摘要的准确率,可应用于自动文本摘要提取任务。 展开更多
关键词 文本摘要 sequence-to-sequence模型 语言特征 拷贝机制 Copy-Generator模型
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Mitochondrial targeting sequence of magnetoreceptor MagR:More than just targeting 被引量:2
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作者 Yanqi Zhang Peng Zhang +10 位作者 Junjun Wang Jing Zhang Tianyang Tong Xiujuan Zhou Yajie Zhou Mengke Wei Chuanlin Feng Jinqian Li Xin Zhang Can Xie Tiantian Cai 《Zoological Research》 SCIE CSCD 2024年第3期468-477,共10页
Iron-sulfur clusters(ISC)are essential cofactors for proteins involved in various biological processes,such as electron transport,biosynthetic reactions,DNA repair,and gene expression regulation.ISC assembly protein I... Iron-sulfur clusters(ISC)are essential cofactors for proteins involved in various biological processes,such as electron transport,biosynthetic reactions,DNA repair,and gene expression regulation.ISC assembly protein IscA1(or MagR)is found within the mitochondria of most eukaryotes.Magnetoreceptor(MagR)is a highly conserved A-type iron and iron-sulfur cluster-binding protein,characterized by two distinct types of iron-sulfur clusters,[2Fe-2S]and[3Fe-4S],each conferring unique magnetic properties.MagR forms a rod-like polymer structure in complex with photoreceptive cryptochrome(Cry)and serves as a putative magnetoreceptor for retrieving geomagnetic information in animal navigation.Although the N-terminal sequences of MagR vary among species,their specific function remains unknown.In the present study,we found that the N-terminal sequences of pigeon MagR,previously thought to serve as a mitochondrial targeting signal(MTS),were not cleaved following mitochondrial entry but instead modulated the efficiency with which iron-sulfur clusters and irons are bound.Moreover,the N-terminal region of MagR was required for the formation of a stable MagR/Cry complex.Thus,the N-terminal sequences in pigeon MagR fulfil more important functional roles than just mitochondrial targeting.These results further extend our understanding of the function of MagR and provide new insights into the origin of magnetoreception from an evolutionary perspective. 展开更多
关键词 Magnetoreceptor(MagR) N-terminal sequence Mitochondrial targeting signal Iron-sulfur cluster
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The Application of Nicotiana benthamiana as a Transient Expression Host to Clone the Coding Sequences of Plant Genes
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作者 Jianzhong Huang Peng Jia +3 位作者 Xiaoju Zhong Xiuying Guan Hongbin Zhang Honglei Ruan 《American Journal of Molecular Biology》 CAS 2024年第2期54-65,共12页
Coding sequences (CDS) are commonly used for transient gene expression, in yeast two-hybrid screening, to verify protein interactions and in prokaryotic gene expression studies. CDS are most commonly obtained using co... Coding sequences (CDS) are commonly used for transient gene expression, in yeast two-hybrid screening, to verify protein interactions and in prokaryotic gene expression studies. CDS are most commonly obtained using complementary DNA (cDNA) derived from messenger RNA (mRNA) extracted from plant tissues and generated by reverse transcription. However, some CDS are difficult to acquire through this process as they are expressed at extremely low levels or have specific spatial and/or temporal expression patterns in vivo. These challenges require the development of alternative CDS cloning technologies. In this study, we found that the genomic intron-containing gene coding sequences (gDNA) from Arabidopsis thaliana, Oryza sativa, Brassica napus, and Glycine max can be correctly transcribed and spliced into mRNA in Nicotiana benthamiana. In contrast, gDNAs from Triticum aestivum and Sorghum bicolor did not function correctly. In transient expression experiments, the target DNA sequence is driven by a constitutive promoter. Theoretically, a sufficient amount of mRNA can be extracted from the N. benthamiana leaves, making it conducive to the cloning of CDS target genes. Our data demonstrate that N. benthamiana can be used as an effective host for the cloning CDS of plant genes. 展开更多
关键词 Coding sequence Genomic sequence Nicotiana benthamiana Plant Genes
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Pig pangenome graph reveals functional features of non‑reference sequences
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作者 Jian Miao Xingyu Wei +6 位作者 Caiyun Cao Jiabao Sun Yuejin Xu Zhe Zhang Qishan Wang Yuchun Pan Zhen Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期956-970,共15页
Background The reliance on a solitary linear reference genome has imposed a significant constraint on our compre-hensive understanding of genetic variation in animals.This constraint is particularly pronounced for non... Background The reliance on a solitary linear reference genome has imposed a significant constraint on our compre-hensive understanding of genetic variation in animals.This constraint is particularly pronounced for non-reference sequences(NRSs),which have not been extensively studied.Results In this study,we constructed a pig pangenome graph using 21 pig assemblies and identified 23,831 NRSs with a total length of 105 Mb.Our findings revealed that NRSs were more prevalent in breeds exhibiting greater genetic divergence from the reference genome.Furthermore,we observed that NRSs were rarely found within coding sequences,while NRS insertions were enriched in immune-related Gene Ontology terms.Notably,our investigation also unveiled a close association between novel genes and the immune capacity of pigs.We observed substantial differences in terms of frequencies of NRSs between Eastern and Western pigs,and the heat-resistant pigs exhibited a substantial number of NRS insertions in an 11.6 Mb interval on chromosome X.Additionally,we discovered a 665 bp insertion in the fourth intron of the TNFRSF19 gene that may be associated with the ability of heat tolerance in South-ern Chinese pigs.Conclusions Our findings demonstrate the potential of a graph genome approach to reveal important functional features of NRSs in pig populations. 展开更多
关键词 Heat tolerance Immune ability Non-reference sequences Pig pangenome
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Phylogenetic, phylogeographic and divergence time analysis of Anopheles subpictus species complex using ITS2 and COI sequences
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作者 Lihini Sandaleka Muthukumarana Methsala Madurangi Wedage +1 位作者 Samanthika Rathnayake Nissanka Kolitha De Silva 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第5期214-225,I0004-I0038,共47页
Objective:To address the phylogenetic and phylogeographic relationship between different lineages of Anopheles(An.)subpictus species complex in most parts of the Asian continent by maximum utilization of Internal Tran... Objective:To address the phylogenetic and phylogeographic relationship between different lineages of Anopheles(An.)subpictus species complex in most parts of the Asian continent by maximum utilization of Internal Transcriber Spacer 2(ITS2)and cytochrome C oxidase I(COI)sequences deposited at the GenBank.Methods:Seventy-five ITS2,210 COI and 26 concatenated sequences available in the NCBI database were used.Phylogenetic analysis was performed using Bayesian likelihood trees,whereas median-joining haplotype networks and time-scale divergence trees were generated for phylogeographic analysis.Genetic diversity indices and genetic differentiation were also calculated.Results:Two genetically divergent molecular forms of An.subpictus species complex corresponding to sibling species A and B are established.Species A evolved around 37-82 million years ago in Sri Lanka,India,and the Netherlands,and species B evolved around 22-79 million years ago in Sri Lanka,India,and Myanmar.Vietnam,Thailand,and Cambodia have two molecular forms:one is phylogenetically similar to species B.Other forms differ from species A and B and evolved recently in the above mentioned countries,Indonesia and the Philippines.Genetic subdivision among Sri Lanka,India,and the Netherlands is almost absent.A substantial genetic differentiation was obtained for some populations due to isolation by large geographical distances.Genetic diversity indices reveal the presence of a long-established stable mosquito population,at mutation-drift equilibrium,regardless of population fluctuations.Conclusions:An.subpictus species complex consists of more than two genetically divergent molecular forms.Species A is highly divergent from the rest.Sri Lanka and India contain only species A and B. 展开更多
关键词 Molecular systematics ITS2 COI DNA sequences Phylogeny PHYLOGEOGRAPHY
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On power series statistical convergence and new uniform integrability of double sequences
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作者 Sevda Y■ld■z Kamil Demirci 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期519-532,共14页
In the present paper,we mostly focus on P_(p)^(2)-statistical convergence.We will look into the uniform integrability via the power series method and its characterizations for double sequences.Also,the notions of P_(p... In the present paper,we mostly focus on P_(p)^(2)-statistical convergence.We will look into the uniform integrability via the power series method and its characterizations for double sequences.Also,the notions of P_(p)^(2)-statistically Cauchy sequence,P_(p)^(2)-statistical boundedness and core for double sequences will be described in addition to these findings. 展开更多
关键词 power series methods statistical convergence uniform integrability double sequences
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A cloud model target damage effectiveness assessment algorithm based on spatio-temporal sequence finite multilayer fragments dispersion
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作者 Hanshan Li Xiaoqian Zhang Junchai Gao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期48-64,共17页
To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept,this paper proposes a method for calculating target damage p... To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept,this paper proposes a method for calculating target damage probability leveraging spatio-temporal finite multilayer fragments distribution and the target damage assessment algorithm based on cloud model theory.Drawing on the spatial dispersion characteristics of fragments of projectile proximity explosion,we divide into a finite number of fragments distribution planes based on the time series in space,set up a fragment layer dispersion model grounded in the time series and intersection criterion for determining the effective penetration of each layer of fragments into the target.Building on the precondition that the multilayer fragments of the time series effectively assail the target,we also establish the damage criterion of the perforation and penetration damage and deduce the damage probability calculation model.Taking the damage probability of the fragment layer in the spatio-temporal sequence to the target as the input state variable,we introduce cloud model theory to research the target damage assessment method.Combining the equivalent simulation experiment,the scientific and rational nature of the proposed method were validated through quantitative calculations and comparative analysis. 展开更多
关键词 Target damage Cloud model Fragments dispersion Effectiveness assessment Spatio-temporal sequence
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The Upper Jurassic sediments,Marib-Shabwa Basin,Yemen:Lithofacies aspects and sequence stratigraphic analysis
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作者 Mohammed Albaroot Mohamed M.Elhossainy +2 位作者 Nabil M.Al-Areeq Emad A.Abdullah Abdelhamid M.Salman 《Energy Geoscience》 EI 2024年第1期342-357,共16页
The present study is devoted to understanding the evolution of the Upper Jurassic Sab'atayn Formation in the Marib-Shabwa Basin,Yemen,through a sequence stratigraphic analysis based on integrating datasets of sedi... The present study is devoted to understanding the evolution of the Upper Jurassic Sab'atayn Formation in the Marib-Shabwa Basin,Yemen,through a sequence stratigraphic analysis based on integrating datasets of sedimentology,seismic sections,and well logs.The Sab'atayn Formation(Tithonian age)is represented by a series of clastic and evaporites that were deposited under fluvio-deltaic to prodeltaic settings.It is divided into four members including Yah(at the base),upwards to Seen,Alif,and Safir at the top.Two third-order depositional sequences were determined for the Tithonian succession which were separated by three sequence boundaries.These sequences were classified into their systems tracts signifying several sedimentation patterns of progradational,aggradational,and retrogradational parasequence sets.The first depositional sequence corresponds to the early-middle Tithonian Yah and Seen units that can be classified into lowstand,transgressive,and highstand systems tracts.The second sequence comprises the late Tithonian Alif unit that can be subdivided into transgressive and highstand systems tracts.The sandy deposits of the Alif Member(highstand deposits)represent the most productive hydrocarbon reservoir in the basin.The Upper Jurassic sediments in the study area were resulted from a combination of eustatic and tectonic effects. 展开更多
关键词 sequence stratigraphy Sandstone reservoir Well logs Upper Jurassic Marib-Shabwa Basin Yemen
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Landscape of Sequence Variations in Homologous Copies of FAD2 and FAD3 in Rapeseed(Brassica napus L.)Germplasm with High/Low Linolenic Acid Trait
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作者 Haoxue Wu Xiaohan Zhang +5 位作者 Xiaoyu Chen Kang Li Aixia Xu Zhen Huang Jungang Dong Chengyu Yu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期627-640,共14页
Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har... Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har-bors four and six homologous copies,respectively,of the two fatty acid desaturases FAD2 and FAD3,which con-trol the last two steps of ALA biosynthesis during seed oil accumulation.In this study,we compared their promoters,coding sequences,and expression levels in three high-ALA inbred lines 2006L,R8Q10,and YH25005,a low-ALA line A28,a low-ALA/high-oleic-acid accession SW,and the wildtype ZS11.The expression levels of most FAD2 and FAD3 homologs in the three high-ALA accessions were higher than those in ZS11 and much higher than those in A28 and SW.The three high-ALA accessions shared similar sequences with the pro-moters and CDSs of BnFAD3.C4 and BnFAD3.A3.In A28 and SW,substitution of three amino acid residues in BnFAD2.A5 and BnFAD2.C5,an absence of BnFAD2.C1 locus,and a 549 bp long deletion on the BnFAD3.A3 promoter were detected.The profile of BnFAD2 mutation in the two low-ALA accessions A28 and SW is different from that reported in previous studies.The mutations in BnFAD3 in the high-ALA accessions are reported for thefirst time.In identifying the sites of these mutations,we provide detailed information to aid the design of mole-cular markers for accelerated breeding schemes. 展开更多
关键词 Brassica napus linolenic acid FAD2 FAD3 promoter coding sequences mutation
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Adaptive Successive POI Recommendation via Trajectory Sequences Processing and Long Short-Term Preference Learning
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作者 Yali Si Feng Li +3 位作者 Shan Zhong Chenghang Huo Jing Chen Jinglian Liu 《Computers, Materials & Continua》 SCIE EI 2024年第10期685-706,共22页
Point-of-interest(POI)recommendations in location-based social networks(LBSNs)have developed rapidly by incorporating feature information and deep learning methods.However,most studies have failed to accurately reflec... Point-of-interest(POI)recommendations in location-based social networks(LBSNs)have developed rapidly by incorporating feature information and deep learning methods.However,most studies have failed to accurately reflect different users’preferences,in particular,the short-term preferences of inactive users.To better learn user preferences,in this study,we propose a long-short-term-preference-based adaptive successive POI recommendation(LSTP-ASR)method by combining trajectory sequence processing,long short-term preference learning,and spatiotemporal context.First,the check-in trajectory sequences are adaptively divided into recent and historical sequences according to a dynamic time window.Subsequently,an adaptive filling strategy is used to expand the recent check-in sequences of users with inactive check-in behavior using those of similar active users.We further propose an adaptive learning model to accurately extract long short-term preferences of users to establish an efficient successive POI recommendation system.A spatiotemporal-context-based recurrent neural network and temporal-context-based long short-term memory network are used to model the users’recent and historical checkin trajectory sequences,respectively.Extensive experiments on the Foursquare and Gowalla datasets reveal that the proposed method outperforms several other baseline methods in terms of three evaluation metrics.More specifically,LSTP-ASR outperforms the previously best baseline method(RTPM)with a 17.15%and 20.62%average improvement on the Foursquare and Gowalla datasets in terms of the Fβmetric,respectively. 展开更多
关键词 Location-based social networks adaptive successive point-of-interest recommendation long short-term preference trajectory sequences
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Secure Transmission of Compressed Medical Image Sequences on Communication Networks Using Motion Vector Watermarking
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作者 Rafi Ullah Mohd Hilmi bin Hasan +1 位作者 Sultan Daud Khan Mussadiq Abdul Rahim 《Computers, Materials & Continua》 SCIE EI 2024年第3期3283-3301,共19页
Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all whil... Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all while upholding image quality.Moreover,an increasing number of hospitals are embracing cloud computing for patient data storage,necessitating meticulous scrutiny of server security and privacy protocols.Nevertheless,considering the widespread availability of multimedia tools,the preservation of digital data integrity surpasses the significance of compression alone.In response to this concern,we propose a secure storage and transmission solution for compressed medical image sequences,such as ultrasound images,utilizing a motion vector watermarking scheme.The watermark is generated employing an error-correcting code known as Bose-Chaudhuri-Hocquenghem(BCH)and is subsequently embedded into the compressed sequence via block-based motion vectors.In the process of watermark embedding,motion vectors are selected based on their magnitude and phase angle.When embedding watermarks,no specific spatial area,such as a region of interest(ROI),is used in the images.The embedding of watermark bits is dependent on motion vectors.Although reversible watermarking allows the restoration of the original image sequences,we use the irreversible watermarking method.The reason for this is that the use of reversible watermarks may impede the claims of ownership and legal rights.The restoration of original data or images may call into question ownership or other legal claims.The peak signal-to-noise ratio(PSNR)and structural similarity index(SSIM)serve as metrics for evaluating the watermarked image quality.Across all images,the PSNR value exceeds 46 dB,and the SSIM value exceeds 0.92.Experimental results substantiate the efficacy of the proposed technique in preserving data integrity. 展开更多
关键词 Block matching algorithm(BMA) compression full-search algorithm motion vectors ultrasound image sequence WATERMARKING
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Optimal mining sequence for coal faces under a bedding slope:insight from landslide prevention
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作者 LI Qingmiao ZHAO Jianjun +3 位作者 LI Zhichao DENG Jie ZUO Jing LAI Qiyi 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1775-1798,共24页
Repetitive mining beneath bedding slopes is identified as a critical factor in geomorphic disturbances, especially landslides and surface subsidence. Prior research has largely concentrated on surface deformation in p... Repetitive mining beneath bedding slopes is identified as a critical factor in geomorphic disturbances, especially landslides and surface subsidence. Prior research has largely concentrated on surface deformation in plains due to multi-seam coal mining and the instability of natural bedding slopes, yet the cumulative impact of different mining sequences on bedding slopes has been less explored. This study combines drone surveys and geological data to construct a comprehensive three-dimensional model of bedding slopes. Utilizing FLAC3D and PFC2D models, derived from laboratory experiments, it simulates stress, deformation, and failure dynamics of slopes under various mining sequences. Incorporating fractal dimension analysis, the research evaluates the stability of slopes in relation to different mining sequences. The findings reveal that mining in an upslope direction minimizes disruption to overlying strata. Initiating extraction from lower segments increases tensile-shear stress in coal pillar overburdens, resulting in greater creep deformation towards the downslope than when starting from upper segments, potentially leading to localized landslides and widespread creep deformation in mined-out areas. The downslope upward mining sequence exhibits the least fractal dimensions, indicating minimal disturbance to both strata and surface. While all five mining scenarios maintain good slope stability under normal conditions, recalibrated stability assessments based on fractal dimensions suggest that downslope upward mining offers the highest stability under rainfall, contrasting with the lower stability and potential instability risks of upslope downward mining. These insights are pivotal for mining operations and geological hazard mitigation in multi-seam coal exploitation on bedding slopes. 展开更多
关键词 Bedding rock landslides Mining-induced deformation Bedding slope stability Underground mining sequences Fractal-based strength reduction method
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Highlighting relationships between sand thicknesses,reservoir-seal pairs and paleobathymetry from a sequence stratigraphic perspective:An example from Tortonian Serravallian deposits,onshore Niger Delta Basin
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作者 Ifeanyichukwu S.Obi K.Mosto Onuoha Chidozie I.Princeton Dim 《Energy Geoscience》 EI 2024年第1期12-23,共12页
The utilization of sequence stratigraphic concepts in identifying sands and their spatial continuity in distinct gross depositional settings is key,especially in frontier settings where data paucity is a common challe... The utilization of sequence stratigraphic concepts in identifying sands and their spatial continuity in distinct gross depositional settings is key,especially in frontier settings where data paucity is a common challenge.In the Baka field,onshore Niger Delta,detailed reservoir correlation guided by sequence stratigraphic framework analysis showed the distribution of sand and shale units constituting reservoirseal pairs(RSP)correlatable across the field.Within the 3rd-order packages,it is observed that the lowstand systems tract(LST)and highstand systems tract(HST)contain more RSPs and thicker 4th-and 5th-order sands than the transgressive systems tract(TST).In terms of bathymetry,it is noted that irrespective of systems tracts,the RSP Index(RI)decreases from the proximal shallow/inner shelf settings to the more distal outer shelf areas.Amongst all three systems tracts,intervals interpreted as lowstand prograding complexes contain the best developed sands and highest RSP.Sand development within the LSTs has been controlled by a pronounced growth fault regime accompanied by high subsidence and sedimentation rates.This is linked to the basinward migration of the sands during prolonged sea-level fall,creating significant accommodation space for sand deposition.On the other hand,the TSTs known to mark periods of progressive sea-level rise and landward migration of sandy facies,show thinner sands enclosed in much thicker,laterally extensive,and better-preserved deeper marine shales.Interpreted seismic sections indicate intense growth faulting and channelization that influenced the syn-and postdepositional development of the sand packages across the field.The initial timing of deformation of subregional faults in this area coincides with periods of abrupt falls in sea level.This approach could be useful for predicting sand-prone areas in frontier fields as well as possible reservoir-seal parameters required for some aspects of petroleum system analysis and quick-look volume estimation. 展开更多
关键词 Reservoir-seal pairs(RSP) Systems tract Coastal swamp depobelt Bathymetry sequence stratigraphy Niger Delta Basin
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Method and Description of Sedimentary System Characterization Based on Sequence Stratigraphy
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作者 Jianmin Zhang Hui Cai +1 位作者 Honglin Yue Pengfei Mu 《Journal of Geoscience and Environment Protection》 2024年第5期60-68,共9页
A Oilfield is the most representative mid to deep oil field in the Bohai Sea, with the main oil bearing intervals being the upper and middle Shahejie-3 sections of the Paleogene Shahejie Formation. By combining well s... A Oilfield is the most representative mid to deep oil field in the Bohai Sea, with the main oil bearing intervals being the upper and middle Shahejie-3 sections of the Paleogene Shahejie Formation. By combining well seismic analysis, the middle section of Shahejie-3 is divided into high-level system tract and forced lake retreat system tract, corresponding to the II oil formation and I oil formation, respectively. Using sequence stratigraphy methods, based on seismic profiles and drilling lithological cycles, the high stand system tract is divided into 5 stages of delta progradation. The first and second stages are high angle S-type progradation with large sedimentary thickness, the third stage is oblique progradation, and the fourth and fifth stages are S-oblique composite progradation;By combining seismic data, we characterized the large-scale (8 small-scale) progradation bodies of 5 periods, clarified the distribution characteristics of reservoir planes, and laid the foundation for the later exploration of oilfield potential. 展开更多
关键词 Middle Section of Shasan sequence Stratigraphy Sedimentary System CHARACTERIZATION
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Coseismic Coulomb stress changes induced by a 2020-2021 M_(W)>7.0 Alaska earthquake sequence in and around the Shumagin gap and its influence on the Alaska-Aleutian subduction interface
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作者 Lei Yang Jianjun Wang Caijun Xu 《Geodesy and Geodynamics》 EI CSCD 2024年第1期1-12,共12页
Three M_(W)>7.0 earthquakes in 2020-2021 occurred in the Shumagin seismic gap and its adjacent area of the Alaska-Aleutian subduction zone,including the Mw7.8 Simeonof thrust earthquake on July 22,2020,the M_(W)7.6... Three M_(W)>7.0 earthquakes in 2020-2021 occurred in the Shumagin seismic gap and its adjacent area of the Alaska-Aleutian subduction zone,including the Mw7.8 Simeonof thrust earthquake on July 22,2020,the M_(W)7.6 Sand Point strike-slip earthquake on October 19,2020,and the M_(W)8.2 Chignik thrust earthquake on July 29,2021.The spatial and temporal proximity of these three earthquakes prompts us to probe stress-triggering effects among them.Here we examine the coseismic Coulomb stress change imparted by the three earthquakes and their influence on the subduction interface.Our results show that:(1)The Simeonof earthquake has strong loading effects on the subsequent Sand Point and Chignik earthquakes,with the Coulomb stress changes of 3.95 bars and 2.89 bars,respectively.The Coulomb stress change caused by the Sand Point earthquake at the hypocenter of the Chignik earthquake is merely around 0.01 bars,suggesting the negligible triggering effect on the latter earthquake;(2)The triggering effects of the Simeonof,Sand Point,and Chignik earthquakes on aftershocks within three months are not well pronounced because of the triggering rates of 38%,14%,and 43%respectively.Other factors may have played an important role in promoting the occurrence of these aftershocks,such as the roughness of the subduction interface,the complicated velocity structure of the lithosphere,and the heterogeneous prestress therein;(3)The three earthquakes caused remarkable coseismic Coulomb stress changes at the subduction interface nearby these mainshocks,with an average Coulomb stress change of 3.2 bars in the shallow region directly inwards the trench. 展开更多
关键词 The 2020-2021 Alaska earthquake sequence Coseismic Coulomb stress change Mainshock-aftershock triggering The Alaska-Aleutian subduction interface The Shumagin gap
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Intelligent extraction of road cracks based on vehicle laser point cloud and panoramic sequence images
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作者 Ming Guo Li Zhu +4 位作者 Ming Huang Jie Ji Xian Ren Yaxuan Wei Chutian Gao 《Journal of Road Engineering》 2024年第1期69-79,共11页
In light of the limited efficacy of conventional methods for identifying pavement cracks and the absence of comprehensive depth and location data in two-dimensional photographs,this study presents an intelligent strat... In light of the limited efficacy of conventional methods for identifying pavement cracks and the absence of comprehensive depth and location data in two-dimensional photographs,this study presents an intelligent strategy for extracting road cracks.This methodology involves the integration of laser point cloud data obtained from a vehicle-mounted system and a panoramic sequence of images.The study employs a vehicle-mounted LiDAR measurement system to acquire laser point cloud and panoramic sequence image data simultaneously.A convolutional neural network is utilized to extract cracks from the panoramic sequence image.The extracted sequence image is then aligned with the laser point cloud,enabling the assignment of RGB information to the vehicle-mounted three dimensional(3D)point cloud and location information to the two dimensional(2D)panoramic image.Additionally,a threshold value is set based on the crack elevation change to extract the aligned roadway point cloud.The three-dimensional data pertaining to the cracks can be acquired.The experimental findings demonstrate that the use of convolutional neural networks has yielded noteworthy outcomes in the extraction of road cracks.The utilization of point cloud and image alignment techniques enables the extraction of precise location data pertaining to road cracks.This approach exhibits superior accuracy when compared to conventional methods.Moreover,it facilitates rapid and accurate identification and localization of road cracks,thereby playing a crucial role in ensuring road maintenance and traffic safety.Consequently,this technique finds extensive application in the domains of intelligent transportation and urbanization development.The technology exhibits significant promise for use in the domains of intelligent transportation and city development. 展开更多
关键词 Road crack extraction Vehicle laser point cloud Panoramic sequence images Convolutional neural network
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Influence of Production Sequence of Aluminum Alloy Hot Rolling on Strip Surface Quality
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作者 Hui Song Weixuan Jiang 《Frontiers of Metallurgical Industry》 2024年第1期12-14,共3页
With the intensification of market competition in the aluminum alloy strip processing industry,it is dif-ficult to control the mass production of the same specifications,which is bound to affect the hot rolling produc... With the intensification of market competition in the aluminum alloy strip processing industry,it is dif-ficult to control the mass production of the same specifications,which is bound to affect the hot rolling production.This paper studied the effect of the hot rolling order of aluminum alloy on the surface quality of strip,such as roll printing,color difference,anodic oxidation,etc.,reasonable discharge sequence and corresponding optimization measures were formulated. 展开更多
关键词 hot rolling production sequence surface quality aluminum alloy chromate treatment
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基于MSPA和MCR模型的庐山市生态网络构建 被引量:3
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作者 李华 郑育桃 +1 位作者 黄荷 陈飞平 《中南林业科技大学学报》 CAS CSCD 北大核心 2024年第2期98-107,共10页
【目的】在生态环境形势严峻的背景下,构建生态网络是连接破碎化斑块间的重要纽带,是保障物种迁徙交流的有效途径。【方法】以庐山市为研究对象,以GIS技术为核心,利用MSPA法对庐山市进行景观格局分析,再运用景观连通性评价法选取重要生... 【目的】在生态环境形势严峻的背景下,构建生态网络是连接破碎化斑块间的重要纽带,是保障物种迁徙交流的有效途径。【方法】以庐山市为研究对象,以GIS技术为核心,利用MSPA法对庐山市进行景观格局分析,再运用景观连通性评价法选取重要生态源地;其次采用AHP分析法结合专家打分法建立阻力因子评价体系构建阻力面,再基于MCR模型完成庐山市生态网络的构建,运用重力模型选取重要潜在生态廊道,给出生态网络的优化对策,最后应用生态网络分析法,对出生态网络的可行性进行分析。【结果】1)庐山市10处重要生态源地的面积为37 946.52 hm^(2),庐山和鄱阳湖为两处大型生态源地;2)遴选出19条重要生态廊道长为297.05 km,主要分布于中部地区;3)构成生态廊道的景观三要素分别为林地、水系和耕地,廊道宽度设置为300 m;4)构建形成“两区两带三轴”的生态安全格局。【结论】研究区内中心城区及中南部地区斑块分布零碎,景观连通性差,缺少生物栖息活动的绿色空间,应大力改善两地的生态环境,生态绿廊由两地内部向外部空间延伸构建,最终绿廊绿道交织成网覆盖全域,新增3个生态核心节点和9条重要生态廊道后的网络连接指数明显提高,表明构建的庐山市生态网络可行性较强。研究结果对于庐山市的城市绿地系统规划、生态园林城市的建设和生物多样性保护具有一定的指导意义。 展开更多
关键词 MSPA 生态网络 MCR模型 庐山市 重力模型
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小学生跨学科素养测评模型构建与应用研究 被引量:1
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作者 罗士琰 张辉蓉 +3 位作者 宋乃庆 梅涵 唐诗玲雅 佟明辉 《中国电化教育》 CSSCI 北大核心 2024年第5期9-16,共8页
跨学科素养是小学生学习发展的关键素养,构建科学、合理的跨学科素养测评模型是开展小学生跨学科素养有效监测与提升的重要保证,对打破学科知识壁垒、培育新时代拔尖创新人才具有重要现实意义。研究遵循成熟的教育测评模型构建范式,厘... 跨学科素养是小学生学习发展的关键素养,构建科学、合理的跨学科素养测评模型是开展小学生跨学科素养有效监测与提升的重要保证,对打破学科知识壁垒、培育新时代拔尖创新人才具有重要现实意义。研究遵循成熟的教育测评模型构建范式,厘清了小学生跨学科素养操作性定义,构建了包含跨学科知识、跨学科能力和跨学科情意3个一级指标、8个二级指标的小学生跨学科素养测评指标体系,开发了《小学生跨学科素养测评量表》,基于探索性、验证性因素分析以及层次分析法,构建了小学生跨学科素养测评模型:Y=0.306*Y1+0.412*Y2+0.282*Y3,其中Y表示小学生跨学科素养,Y1、Y2、Y3分别表示跨学科知识、跨学科能力、跨学科情意。应用该模型对全国东、中、西部地区12省市的18166名小学4—6年级学生进行测评,初步验证了模型的科学性、有效性与可操作性,并依据测评结果提出提升小学生跨学科素养的对策建议。 展开更多
关键词 小学生 跨学科素养 测评模型 模型构建 模型应用
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数字经济对体育产业高质量发展的影响——基于中介模型和门槛模型的检验 被引量:4
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作者 苏伟洲 肖丹 +2 位作者 谭宏 李坤雨 车召丽 《上海体育大学学报》 CSSCI 北大核心 2024年第1期94-104,共11页
对我国19个省级行政区2012—2021年的面板数据进行实证分析,通过建立中介模型和门槛模型探究数字经济与我国体育产业高质量发展的关系。结果显示:①在固定效应模型的基础上进行实证分析发现,数字经济对体育产业高质量发展产生推动作用;... 对我国19个省级行政区2012—2021年的面板数据进行实证分析,通过建立中介模型和门槛模型探究数字经济与我国体育产业高质量发展的关系。结果显示:①在固定效应模型的基础上进行实证分析发现,数字经济对体育产业高质量发展产生推动作用;②在数字经济促进体育产业高质量发展过程中,产业结构作为中介变量、科技创新作为调节变量在其中起到相应的促进作用;③数字经济与体育产业高质量发展之间显著存在产业结构一阶门槛和科技创新二阶门槛效应。提出:应从提升数字经济发展水平、优化产业结构以及提升科技创新水平等方面促进体育产业高质量发展,推进社会主义现代化体育强国建设。 展开更多
关键词 体育产业高质量发展 数字经济 产业结构 科技创新 中介模型 门槛模型
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