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矛盾式表达——兼谈该类网络流行语的认知理据及流行动因
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作者 马若宏 《南昌师范学院学报》 2024年第1期106-110,共5页
矛盾式表达是一种特殊的语言加工及修辞策略。将语义相反或不搭配的语言要素并置,表达事物、事理或认识的复杂情况,从而达到出人意料的表达效果。通过考察近二十年网络流行语,将以矛盾式表达为生成机制的流行语析出,并归纳为三种结构语... 矛盾式表达是一种特殊的语言加工及修辞策略。将语义相反或不搭配的语言要素并置,表达事物、事理或认识的复杂情况,从而达到出人意料的表达效果。通过考察近二十年网络流行语,将以矛盾式表达为生成机制的流行语析出,并归纳为三种结构语义类型:构式压制型、非常规修饰关系型及对立比照型。进一步讨论矛盾式网络流行语以“语义矛盾”为认知理据,因人们认识更新现象思辨、情感表达及文化需求以及网络求新立异的语用需求为流行动因,已成为值得关注、能产性较高的一类网络流行语。 展开更多
关键词 社会语言学 矛盾表达 网络流行语 认知理据 流行动因
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Multiplicative Lévy noise-induced transitions in gene expression 被引量:1
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作者 SONG Yi XU Wei NIU LiZhi 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2022年第8期1700-1709,共10页
Gene expression is intrinsically noisy. Experimental studies have shown that random fluctuations are large bursts and heavytailed distributions. Therefore, this study aims to consider transition dynamics in a gene tra... Gene expression is intrinsically noisy. Experimental studies have shown that random fluctuations are large bursts and heavytailed distributions. Therefore, this study aims to consider transition dynamics in a gene transcriptional regulatory system via the mean first exit time(MFET) and first escape probability(FEP), when the degradation rate is under multiplicative non-Gaussian Lévy fluctuations in the sense of It? and Marcus forms. We find that, in the Marcus form case, the FEP corresponding to different stability index and noise intensity has an intersection point, whereas in the It? form case, the turning point only occurs at stability index. Increasing the initial CI concentration is helpful for improving the likelihood of transcription in both cases. Our results also imply that larger jumps of Lévy noise and smaller noise intensity can shorten the time of state transition to boost protein production. 展开更多
关键词 gene expression transition dynamics multiplicative Lévy noise It?and Marcus integral
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iHypoxia:An Integrative Database of Protein Expression Dynamics in Response to Hypoxia in Animals
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作者 Ze-Xian Liu Panqin Wang +8 位作者 Qingfeng Zhang Shihua Li Yuxin Zhang Yutong Guo Chongchong Jia Tian Shao Lin Li Han Cheng Zhenlong Wang 《Genomics, Proteomics & Bioinformatics》 SCIE CAS CSCD 2023年第2期267-277,共11页
Mammals have evolved mechanisms to sense hypoxia and induce hypoxic responses.Recently,high-throughput techniques have greatly promoted global studies of protein expression changes during hypoxia and the identificatio... Mammals have evolved mechanisms to sense hypoxia and induce hypoxic responses.Recently,high-throughput techniques have greatly promoted global studies of protein expression changes during hypoxia and the identification of candidate genes associated with hypoxiaadaptive evolution,which have contributed to the understanding of the complex regulatory networks of hypoxia.In this study,we developed an integrated resource for the expression dynamics of proteins in response to hypoxia(iHypoxia),and this database contains 2589 expression events of 1944 proteins identified by low-throughput experiments(LTEs)and 422,553 quantitative expression events of 33,559 proteins identified by high-throughput experiments from five mammals that exhibit a response to hypoxia.Various experimental details,such as the hypoxic experimental conditions,expression patterns,and sample types,were carefully collected and integrated.Furthermore,8788 candidate genes from diverse species inhabiting low-oxygen environments were also integrated.In addition,we conducted an orthologous search and computationally identified 394,141 proteins that may respond to hypoxia among 48 animals.An enrichment analysis of human proteins identified from LTEs shows that these proteins are enriched in certain drug targets and cancer genes.Annotation of known posttranslational modification(PTM)sites in the proteins identified by LTEs reveals that these proteins undergo extensive PTMs,particularly phosphorylation,ubiquitination,and acetylation.iHypoxia provides a convenient and user-friendly method for users to obtain hypoxia-related information of interest. 展开更多
关键词 HYPOXIA expression dynamics Low-throughput experiment High-throughput experiment Functional annotation
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芒果胶孢炭疽病菌应答菌丝机械损伤产生无性孢子的分子机制 被引量:1
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作者 王丽妍 卢梦瑶 +5 位作者 童悦 徐祥斌 张正科 孟兰环 史学群 宋海超 《植物学报》 CAS CSCD 北大核心 2020年第5期551-563,共13页
胶孢炭疽菌(Colletotrichum gloeosporioides)是引发芒果(Mangifera indica)炭疽病的主要病原体。室内平板培养胶孢炭疽菌不产生或产生很少分生孢子的情况时有发生,但菌丝在机械损伤后24–48小时会产生大量分生孢子。胶孢炭疽菌应答机... 胶孢炭疽菌(Colletotrichum gloeosporioides)是引发芒果(Mangifera indica)炭疽病的主要病原体。室内平板培养胶孢炭疽菌不产生或产生很少分生孢子的情况时有发生,但菌丝在机械损伤后24–48小时会产生大量分生孢子。胶孢炭疽菌应答机械损伤诱导产孢的核心基因及关键代谢通路尚未见报道。基于转录组测序(RNA-seq)技术检测了芒果胶孢炭疽菌菌丝在机械损伤处理后2小时内5个时间点的基因表达变化,对差异表达基因进行GO富集和KEGG代谢通路富集分析,并对菌丝响应胁迫的基因动态表达数据进行分析。基于常微分方程ODE模型结合变量选择技术,构建了动态基因调控网络。结果表明,有417个差异表达基因参与应答胶孢炭疽菌菌丝机械损伤,分属12个聚类模块,有4条通路存在显著富集,分别是丙酮酸代谢、硫代谢、黄曲霉素合成途径和二萜合成途径。结合功能注释筛选出12个应答菌丝损伤胁迫的核心基因。研究结果为后续深入开展芒果胶孢炭疽菌产孢和致病机理研究奠定了重要基础。 展开更多
关键词 芒果 胶孢炭疽菌 损伤胁迫 RNA-SEQ 动态表达
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An Algorithm for the Stochastic Simulation of Gene Expression and Heterogeneous Population Dynamics
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作者 Daniel A.Charlebois Jukka Intosalmi +1 位作者 Dawn Fraser Mads Kærn 《Communications in Computational Physics》 SCIE 2011年第1期89-112,共24页
We present an algorithm for the stochastic simulation of gene expression and heterogeneous population dynamics.The algorithm combines an exact method to simulate molecular-level fluctuations in single cells and a cons... We present an algorithm for the stochastic simulation of gene expression and heterogeneous population dynamics.The algorithm combines an exact method to simulate molecular-level fluctuations in single cells and a constant-number Monte Carlo method to simulate time-dependent statistical characteristics of growing cell populations.To benchmark performance,we compare simulation results with steadystate and time-dependent analytical solutions for several scenarios,including steadystate and time-dependent gene expression,and the effects on population heterogeneity of cell growth,division,and DNA replication.This comparison demonstrates that the algorithm provides an efficient and accurate approach to simulate how complex biological features influence gene expression.We also use the algorithm to model gene expression dynamics within"bet-hedging"cell populations during their adaption to environmental stress.These simulations indicate that the algorithm provides a framework suitable for simulating and analyzing realistic models of heterogeneous population dynamics combining molecular-level stochastic reaction kinetics,relevant physiological details and phenotypic variability. 展开更多
关键词 Constant-number Monte Carlo stochastic simulation algorithm gene expression heterogeneous population dynamics
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An Accelerated Method for Simulating Population Dynamics
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作者 Daniel A.Charlebois Mads Kærn 《Communications in Computational Physics》 SCIE 2013年第7期461-476,共16页
We present an accelerated method for stochastically simulating the dynamics of heterogeneous cell populations.The algorithm combines a Monte Carlo approach for simulating the biochemical kinetics in single cells with ... We present an accelerated method for stochastically simulating the dynamics of heterogeneous cell populations.The algorithm combines a Monte Carlo approach for simulating the biochemical kinetics in single cells with a constant-number Monte Carlo method for simulating the reproductive fitness and the statistical characteristics of growing cell populations.To benchmark accuracy and performance,we compare simulation results with those generated from a previously validated population dynamics algorithm.The comparison demonstrates that the accelerated method accurately simulates population dynamics with significant reductions in runtime under commonly invoked steady-state and symmetric cell division assumptions.Considering the increasing complexity of cell population models,the method is an important addition to the arsenal of existing algorithms for simulating cellular and population dynamics that enables efficient,coarse-grained exploration of parameter space. 展开更多
关键词 Accelerated stochastic simulation algorithm constant-number Monte Carlo gene expression population dynamics and fitness
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Numerical simulation and scaling analysis of elasticity-induced lift force in a viscoelastic fluid between confining surfaces
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作者 Xin Zhao Chao Wei 《Journal of Hydrodynamics》 SCIE EI CSCD 2022年第4期756-766,共11页
How to accurately characterize the lift force on the particles near the solid surfaces is an ongoing challenge in fluid mechanics and microfluidic techniques, especially in a complex system with viscoelastic fluid or/... How to accurately characterize the lift force on the particles near the solid surfaces is an ongoing challenge in fluid mechanics and microfluidic techniques, especially in a complex system with viscoelastic fluid or/and soft surface that is commonly encountered in a biological system. The motions of the particles in vicinity of a surface can be simplified to be a rigid cylinder surrounded by the viscoelastic fluid moving along a substrate which can be rigid or soft according to different cases. In such an inertial free system with a wide range of Weissenberg number (Wi < 5.00, representing the ratio of the elastic force to the viscous force), firstly we numerically evaluate the influence of the systematic parameters, including the polymer viscosity, the geometry and Wi, on the net normal force for a cylinder closely moving along a rigid substrate, and the elasticity-induced lift force in a scaled form. It is shown that a strong shear arises in the viscoelastic confinement between the moving cylinder and the rigid substrate, it leads to the asymmetry of the first normal stress distribution around the cylinder, and thus the lift force. Then, the influence of a soft substrate on the lift force is considered, and we find that the lift force induced by the viscoelastic fluid always dominates in magnitude over that induced by the soft substrate deformation. This work provides a reliable scaling that can be utilized to quantify the elasticity-induced lift force on the particles in a viscoelastic system, such as the micro- and nanofluidic systems in biological applications. 展开更多
关键词 Viscoelastic fluid scaling expression computational fluid dynamics lift force
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基于RNA-seq技术分析野生大麦穗部发育基因的表达谱及其转录动态
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作者 霍福临 熊祝佩 +2 位作者 陈丽琴 聂小军 宋卫宁 《麦类作物学报》 CAS CSCD 北大核心 2022年第6期649-658,共10页
为明确野生大麦穗部发育过程中基因表达的动态变化,以来自以色列的野生大麦Mehula1-2为材料,对其在穗部发育的4个关键时期(开花后3、8、13和18d)进行RNA-seq分析,并与栽培大麦穗部的基因表达谱进行了比较。结果表明,在野生大麦穗发育的... 为明确野生大麦穗部发育过程中基因表达的动态变化,以来自以色列的野生大麦Mehula1-2为材料,对其在穗部发育的4个关键时期(开花后3、8、13和18d)进行RNA-seq分析,并与栽培大麦穗部的基因表达谱进行了比较。结果表明,在野生大麦穗发育的4个时间点共鉴定到17163个基因,其中11273个为差异表达基因,包括635个转录因子相关基因;功能富集分析表明,这些差异基因主要富集到物质合成、代谢过程、物质运输、抗逆等相关过程或通路上;野生大麦和栽培大麦穗部基因的表达谱比较分析发现,两者共同表达的基因显著富集到细胞器、催化、代谢、调节及抗逆等相关通路上,而在特异表达基因方面,栽培大麦主要集中于甲基转移酶、次生壁生物合成、核糖体蛋白等相关基因,野生大麦主要集中于逆境抗性、花青素合成、钙调蛋白等相关基因。本研究发掘的与穗部发育相关的关键基因,丰富了大麦穗部遗传改良基因资源,为进一步解析野生大麦穗部发育关键基因的表达特性和调控机制奠定了基础。 展开更多
关键词 野生大麦 转录组学 基因表达 转录动态
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携带DEV-gB基因重组质粒减毒沙门氏菌在鸭免疫器官中的表达动态
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作者 刘妍罕 王相金 +5 位作者 胡安东 曾茂芹 杨颖 温贵兰 程振涛 文明 《山地农业生物学报》 2021年第6期37-43,共7页
为明确含DEV-gB基因重组减毒沙门氏菌在鸭免疫器官中的分布动态,本研究将重组减毒沙门氏菌口服接种鸭(即重组细菌组),同时设立重组质粒组、弱毒疫苗组和空白对照组,于免疫后第7、14、21、28、35、42和49天时,捕杀试验鸭,采集鸭脾脏、胸... 为明确含DEV-gB基因重组减毒沙门氏菌在鸭免疫器官中的分布动态,本研究将重组减毒沙门氏菌口服接种鸭(即重组细菌组),同时设立重组质粒组、弱毒疫苗组和空白对照组,于免疫后第7、14、21、28、35、42和49天时,捕杀试验鸭,采集鸭脾脏、胸腺、法氏囊和哈德氏腺等免疫器官,采用间接免疫荧光法进行DEV-gB抗原检测观察,结果显示:空白对照组鸭免疫器官在7个时间点均未检测到DEV-gB抗原信号;免疫后,重组细菌组、弱毒疫苗组和重组质粒组鸭免疫器官均能检测到DEV抗原阳性信号,但含DEV抗原阳性信号细胞数量从多到少的组别顺序是弱毒疫苗组、重组细菌组和重组质粒组,且重组细菌组与弱毒疫苗组差异不显著(P>0.05);检出含DEV抗原阳性信号的免疫器官先后顺序是脾脏、法氏囊、哈德氏腺和胸腺,而含DEV抗原阳性信号细胞数量从多到少的免疫器官顺序是脾脏、法氏囊、胸腺和哈德氏腺。由此可见,本研究构建的携带DEV-gB基因重组减毒沙门氏菌能在鸭免疫器官中得到良好的表达,为该重组细菌疫苗的临床应用奠定了理论基础。 展开更多
关键词 DEV 重组减毒沙门氏菌 表达动态
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Transcriptional Regulation of the Ambient Temperature Response by H2A.Z Nucleosomes and HSF1 Transcription Factors in Arabidopsis 被引量:17
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作者 Sandra Cortijo Varodom Charoensawan +6 位作者 Anna Brestovitsky Ruth Buning Charles Ravarani Daniela Rhodes John van Noort Katja E. Jaeger Philip A. Wigge 《Molecular Plant》 SCIE CAS CSCD 2017年第10期1258-1273,共16页
Temperature influences the distribution, range, and phenology of plants. The key transcriptional activators of heat shock response in eukaryotes, the heat shock factors (HSFs), have undergone large-scale gene amplif... Temperature influences the distribution, range, and phenology of plants. The key transcriptional activators of heat shock response in eukaryotes, the heat shock factors (HSFs), have undergone large-scale gene amplification in plants. While HSFs are central in heat stress responses, their role in the response to ambient temperature changes is less well understood. We show here that the warm ambient temperature transcriptome is dependent upon the HSFA1 clade ofArabidopsis HSFs, which cause a rapid and dynamic eviction of H2A.Z nucleosomes at target genes. A transcriptional cascade results in the activation of multiple downstream stress-responsive transcription factors, triggering large-scale changes to the transcriptome in response to elevated temperature. H2A.Z nucleosomes are enriched at temperature-responsive genes at non-inducible temperature, and thus likely confer inducibility of gene expression and higher responsive dynamics. We propose that the antagonistic effects of H2A.Z and HSF1 provide a mechanism to activate gene expression rapidly and precisely in response to temperature, while preventing leaky transcription in the absence of an activation signal. 展开更多
关键词 gene expression regulation plant temperature sensing and signaling TRANSCRIPTOMICS nucleosome dynamics histone variant H2A.Z heat shock transcription factors
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影响跑步运动耐力的生理学与生物力学因素 被引量:9
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作者 李天义 徐琳 徐盛嘉 《中国组织工程研究》 CAS 北大核心 2020年第20期3240-3247,共8页
背景:跑步经济性被认为是反映耐力运动员尤其是长跑运动员性能的重要指标,通常定义为在给定速度下跑步的能量需求,表示为给定速度下的摄氧量。目的:综述现有的影响跑步性能的生理学与生物力学因素。方法:以“running economy,physiologi... 背景:跑步经济性被认为是反映耐力运动员尤其是长跑运动员性能的重要指标,通常定义为在给定速度下跑步的能量需求,表示为给定速度下的摄氧量。目的:综述现有的影响跑步性能的生理学与生物力学因素。方法:以“running economy,physiological factors,biomechanical and neuromuscular characteristics,spatiotemporal factors,lower Limb kinematic factors,kinetic factors,nutritional interventions”为检索词,检索PubMed数据库(1960至2018年)中与跑步性能、急性或慢性干预措施和其他影响因素等相关的内容。结果与结论:共得到113篇文献,根据纳入排除标准,对其中58篇文献进行分析。①目前证据表明心肺功能、肌纤维类型、肌肉力量、腿部刚度等生理因素与跑步经济性的改善有关,而跑步者的体温变化和弹性势能与跑步经济性的关系目前没有统一结论;②有利于改善跑步经济性的生物力学因素是步幅频率或长度、垂直振荡、下肢惯性力矩、脚趾离地时腿部伸展以及手臂摆动,而足部与地面的接触时间、躯干倾斜等因素与跑步经济性之间呈现出不一致的关系;③其他的影响因素中,高海拔适应可改善跑步经济性;伸展性和灵活性与跑步经济性之间的关系仍待确定;一些营养干预也受到关注,最明显的是膳食硝酸盐;④尽管该文章已经总结了影响跑步经济性的大部分因素,但未来可以专注于研究个体跑步者,以便确定跑步者的结构和功能能力如何影响跑步经济性,以及后续表现和运动伤害的情况。 展开更多
关键词 跑步经济性的测量与表达 代谢效率 神经肌肉反应 牵拉-缩短周期 肢体动力学
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ABA信号转运调节的基因表达与源库动力学分析 被引量:5
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作者 魏开发 贾文锁 《云南植物研究》 CSCD 北大核心 2009年第4期344-352,共9页
通过对拟南芥NCED3、AAO3及SDR1蛋白亚细胞定位分析及根系和叶片ABA池的动态库变化研究,结果表明气孔运动的有效ABA信号来自于保卫细胞之外,SDR与ABA前体加工和运输有关。胁迫处理后根系合成酶基因转录水平显著高于叶片,但叶片ABA水平... 通过对拟南芥NCED3、AAO3及SDR1蛋白亚细胞定位分析及根系和叶片ABA池的动态库变化研究,结果表明气孔运动的有效ABA信号来自于保卫细胞之外,SDR与ABA前体加工和运输有关。胁迫处理后根系合成酶基因转录水平显著高于叶片,但叶片ABA水平是根系的10倍以上,离体叶片和附体叶片ABA含量测定表明,叶片ABA池的形成主要决定于根源ABA的输入。氟啶酮药剂阻断和遮荫实验说明根系ABA池受叶源类胡萝素前体供应影响。叶片ABA水平受根源ABA和叶源类胡萝素前体库双向转运调节,维管束组织系统可能协同和整合了这一复杂调节机制。该结论为逆境ABA信号转递机制研究和操纵内源ABA含量增强植物抗逆性的应用提供相关资料。 展开更多
关键词 ABA合成酶基因 基因表达 源库动力学 SE—CC复合体 转运调节
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结合FDM与STLBP-IP特征的微表情识别 被引量:1
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作者 韦丽娟 梁建娟 +1 位作者 刘洪 刘本永 《软件导刊》 2021年第4期32-35,共4页
针对面部动力谱(FDM)特征易受光照影响、对运动信息描述不准确的缺陷,提出基于FDM特征与时空局部二值模式积分投影(STLBP-IP)特征相结合的微表情识别方法。将FDM特征与STLBP-IP特征相结合,在弥补FDM对运动信息描述不足的同时对人脸面部... 针对面部动力谱(FDM)特征易受光照影响、对运动信息描述不准确的缺陷,提出基于FDM特征与时空局部二值模式积分投影(STLBP-IP)特征相结合的微表情识别方法。将FDM特征与STLBP-IP特征相结合,在弥补FDM对运动信息描述不足的同时对人脸面部信息进行补充描述以提升识别率。使用支持向量机进行分类,在SMIC和CASMEⅡ微表情数据库上进行实验。实验结果表明,该算法识别率有所提高,分别达到57.14%和64.59%。 展开更多
关键词 微表情识别 机器视觉 面部动力谱 时空局部二值模式积分投影 支持向量机
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微表情识别中面部动力谱特征提取的PCA改进 被引量:1
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作者 涂亮 刘本永 《通信技术》 2019年第2期337-342,共6页
针对用于人脸微表情识别的面部动力谱特征(FDM)提取方法中迭代算法抽取时空立方体主方向时时间复杂度高的问题,提出基于主元分析(PCA)的改进算法。首先将数据中心平移到原点,其次估计相关矩阵,最后估计其特征向量和特征值,取最大特征值... 针对用于人脸微表情识别的面部动力谱特征(FDM)提取方法中迭代算法抽取时空立方体主方向时时间复杂度高的问题,提出基于主元分析(PCA)的改进算法。首先将数据中心平移到原点,其次估计相关矩阵,最后估计其特征向量和特征值,取最大特征值对应的特征向量方向作为时空立方体的主方向。采用Oulu大学SMIC微表情数据库中的微表情片段作为实验样本,选择支持向量机(SVM)作为分类器,对改进算法和原算法进行人脸微表情识别对比实验。结果表明,两种算法识别率相近,但改进算法在计算时间上远短于原算法。可见,改进算法在准确找出时空立方体主方向的同时,能大大降低原算法的计算复杂度。 展开更多
关键词 微表情识别 面部动力谱特征 主元分析 时空立方体 支持向量机
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