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Determination of Focal Depths of the MS5.8 Alxa Left Banner,Inner Mongolia Earthquake Sequence
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作者 Li Bin Wang Shubo +4 位作者 Wei Jianmin Zhang Haoming Liu Yongmei Wu Jun Hao Liang 《Earthquake Research in China》 CSCD 2018年第2期245-253,共9页
Using the double-difference earthquake location algorithm,the deterministic method (PTD method) and the CAP seismic moment tensor inversion method,the paper selects the primary waveform data of 78 earthquakes recorded... Using the double-difference earthquake location algorithm,the deterministic method (PTD method) and the CAP seismic moment tensor inversion method,the paper selects the primary waveform data of 78 earthquakes recorded by the "China Earthquake Science Array Probe Project in the Northern Part of North South Seismic Belt ",the "China Earthquake Scientific Exploration Array Data Center"of Institute of Geophysics,China Earthquake Administration,and the Inner Mongolia Digital Seismic Network to calculate the focal depths of the mainshock and the seismic sequence of the M_S5.8 Alxa Left Banner earthquake in Inner Mongolia. The results show that the focal depth of the main shock is 20. 6 km,determined by the double-difference earthquake location method,18. 1 km by the PTD method,and 19. 2 km by the CAP method. The focal depth of the earthquake sequence calculated by the double-difference location method is larger. The deterministic method (PTD method) and double-difference location method are the methods that fit the tectonic characteristics of the seismic source area,and the CAP method is suitable for larger earthquakes. 展开更多
关键词 EARTHQUAKE sequence FOCAL depth Double-difference EARTHQUAKE location METHOD PTD METHOD CAP METHOD
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Consistent Depth Maps Estimation from Binocular Stereo Video Sequence
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作者 段峰峰 《Journal of Shanghai Jiaotong university(Science)》 EI 2016年第2期184-191,共8页
In the paper, an approach is proposed for the problem of consistency in depth maps estimation from binocular stereo video sequence. The consistent method includes temporal consistency and spatial consistency to elimin... In the paper, an approach is proposed for the problem of consistency in depth maps estimation from binocular stereo video sequence. The consistent method includes temporal consistency and spatial consistency to eliminate the flickering artifacts and smooth inaccuracy in depth recovery. So the improved global stereo matching based on graph cut and energy optimization is implemented. In temporal domain, the penalty function with coherence factor is introduced for temporal consistency, and the factor is determined by Lucas-Kanade optical flow weighted histogram similarity constraint(LKWHSC). In spatial domain, the joint bilateral truncated absolute difference(JBTAD) is proposed for segmentation smoothing. The method can smooth naturally and uniformly in low-gradient region and avoid over-smoothing as well as keep edge sharpness in high-gradient discontinuities to realize spatial consistency. The experimental results show that the algorithm can obtain better spatial and temporal consistent depth maps compared with the existing algorithms. 展开更多
关键词 consistent depth maps binocular stereo video sequence Lucas-Kanade optical flow weighted histogram similarity constraint(LKWHSC) joint bilateral truncated absolute difference(JBTAD)
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冬小麦RIL群体分蘖相关性状QTL定位
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作者 郭小玲 俞天胜 +4 位作者 汪永法 程宇坤 任毅 张晓玉 耿洪伟 《麦类作物学报》 北大核心 2026年第1期58-67,共10页
为进一步挖掘小麦分蘖相关性状的数量性状位点(QTL),探索分蘖性状之间的遗传关系,以分蘖性状差异较大的小麦品种Apache和新冬36号构建的255份重组自交系群体(RIL)为材料,分别测定其在4个环境下的冬前分蘖数、单株分蘖数、单株有效分蘖... 为进一步挖掘小麦分蘖相关性状的数量性状位点(QTL),探索分蘖性状之间的遗传关系,以分蘖性状差异较大的小麦品种Apache和新冬36号构建的255份重组自交系群体(RIL)为材料,分别测定其在4个环境下的冬前分蘖数、单株分蘖数、单株有效分蘖数、单位面积有效分蘖数、分蘖角度、成穗率表型值,并基于RIL群体的超低深度测序数据进行分蘖相关性状QTL定位。结果表明,除1D、2D、3B、4D、7A和7B染色体外,在其他15条染色体上共检测到53个分蘖性状相关的QTL,包括13个冬前分蘖数QTL、10个单株分蘖数QTL、8个单株有效分蘖数QTL、11个单位面积有效分蘖数QTL、4个分蘖角度QTL、2个成穗率QTL和5个一因多效的QTL,单个QTL的表型解释率为2.66%~28.76%。其中,QTn.xjau-4B在3个环境下均被检测到,对单株有效分蘖数表型贡献率为28.76%,为稳定主效QTL,同时也是R-E-Z位点,后续可作为研究分蘖及株型的重要位点。 展开更多
关键词 小麦 分蘖性状 超低深度测序 QTL分析
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Relationship between the earthquake sequences of Tangshan and Xingtai and the three dimensional velocity structure──Discussion on predicting strong earthquakes of swarm-type 被引量:5
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作者 梅世蓉 薛艳 尹京苑 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第2期175-182,共8页
In this paper, based on the results of tomographic image of Tangshan and Xingtai areas, the relations between thecharacteristics of the two strong earthquake sequences and their three-dimensional velocity structures a... In this paper, based on the results of tomographic image of Tangshan and Xingtai areas, the relations between thecharacteristics of the two strong earthquake sequences and their three-dimensional velocity structures are studied.The research results indicate that:① Mosaic distribution of low-velocity bodies and high-velocity bodies, especially the existence of high-velocity bodies with large size in crust are the common basis of development of thetwo earthquake sequences. ② Scale, depth, and heterogeneity of high-velocity and low-velocity bodies are theimportant factors to effect the characteristic of earthquake sequences. ③ The depth of the high-velocity body inTangshan area is less than that in Xingtai area, which is the principal reason why the dominant focal depth and thebiggest focal depth of Tangshan earthquake sequence are less than Xingtai's. ④ The depth of the high-velocitybodies in Ninghe area is more than that in Tangshan-Luanxian area, which lead to the biggest magnitude and epicentral intensity are lower. These results could be helpful for predicting the main shock of strong swarm-typeearthquakes and later strong aftershocks. 展开更多
关键词 strong earthquake sequence low-velocity anomalous body strong swarm-type earthquake dominant focal depth the biggest focal depth of aftershocks
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Spatial distribution features of sequence types of moderate and strong earthquake in Chinese mainland 被引量:5
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作者 蒋海昆 李永莉 +4 位作者 曲延军 华爱军 郑建常 代磊 侯海峰 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2006年第4期417-427,共11页
Based on 294 earthquake sequences with magnitude greater than or equal to 5.0 occurred in Chinese mainland since 1970, the spatial distribution features of sequence types have been studied. In southwestern China, it t... Based on 294 earthquake sequences with magnitude greater than or equal to 5.0 occurred in Chinese mainland since 1970, the spatial distribution features of sequence types have been studied. In southwestern China, it takes mainshock-aftershock sequence type (MAT) as the major in Chuan-Dian rhombic block and concerned Xianshuihe-Anninghe-Xiaojiang seismic belt, as well as in Jinshajiang-Honghe seismic belt. Multiple mainshock type (MMT) mainly distributes in western Yunnan, and Longlin and Lancang areas in Tengchong-Baoshan block in west of Nujiang-Lancangjiang fault zone. A few isolated earthquake type (IET) mainly occurred in northwestern Sichuan and there is no IET occurred in Yunnan region. In northwestern China, it takes mainshock-aftershock sequence type (MAT) as the major in west segment of South Tianshan in Xinjiang region. Some MMT also occurred in this area in the intersection of Kalpin block and the Puchang fault zone. It takes IET as the major in middle Tianshan in Xinjiang. Along the Qilianshan seismic belt, most of sequences are MAT. In Qinghai region, it takes MAT as the major, but the regional feature of the spatial distribution of sequence types is not very clear. In North China, it takes MAT as the major in Yinshan-Yanshan-Bohai seismic belt, north edge of North China, and in Hebei plain seismic belt, as well as in sub-plate of lower river area of Yangtze River. In intersection of north segment of Shanxi seismic belt and the NW-trending Yinshan-Yanshan-Bohai seismic belt, there are several moderate or strong MMT with magnitude from 5.0 to 6.0 occurred. In south of North China around the latitude line of 35°N, it takes IET as the major. The spatial distribution of sequence types is relevant to the patterns of tectonic movements. MAT is mostly produced by the ruptures of locked units or asperities or the neonatal separating segments inside the fault zones. MMT is generally relevant to the conjugate structures or intersection of many tectonic settings. Further extension of simple fault often produces IET. Spatial distribution of sequence types is also correlative to the regional and deep environment of crustal medium to some extent. MAT mainly distributes in high velocity area in upper crust or in the transition zone between high velocity area and low velocity area, MMT mostly occurred in the low velocity area in upper crust. 展开更多
关键词 spatial distribution of sequence types isolated earthquake malnshock-aftershock sequence multi-ple malnshock type patterns of tectonic movement medium environment in depth of the earth
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Study of sedimentary sequence cycles by well-seismic calibration 被引量:4
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作者 Xu Jingling Liu Luofu +2 位作者 Wang Guiwen Zou Changchun Lai Jin 《Petroleum Science》 SCIE CAS CSCD 2013年第1期65-72,共8页
In order to solve the problems of the fine division of sedimentary sequence cycles and their change in two-dimensional space as well as lateral extension contrast, we developed a method of wavelet depth-frequency anal... In order to solve the problems of the fine division of sedimentary sequence cycles and their change in two-dimensional space as well as lateral extension contrast, we developed a method of wavelet depth-frequency analysis. The single signal and composite signal of different Milankovitch cycles are obtained by numerical simulation. The simulated composite signal can be separated into single signals of a single frequency cycle. We also develop a well-seismic calibration insertion technology which helps to realize the calibration from the spectrum characteristics of a single well to the seismic profile. And then we determine the change and distribution characteristics of spectrum cycles in the two-dimensional space. It points out the direction in determining the variations of the regional sedimentary sequence cycles, underground strata structure and the contact relationship. 展开更多
关键词 Sedimentary sequence cycles wavelet depth-frequency analysis well-seismic calibration spectrum cycles well logging
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Differential nonlinear photocarrier radiometry for characterizing ultra-low energy boron implantation in silicon
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作者 Xiao-Ke Lei Bin-Cheng Li +3 位作者 Qi-Ming Sun Jing Wang Chun-Ming Gao Ya-Fei Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第3期575-580,共6页
The measuring of the depth profile and electrical activity of implantation impurity in the top nanometer range of silicon encounters various difficulties and limitations, though it is known to be critical in fabricati... The measuring of the depth profile and electrical activity of implantation impurity in the top nanometer range of silicon encounters various difficulties and limitations, though it is known to be critical in fabrication of silicon complementary metal–oxide–semiconductor(CMOS) devices. In the present work, SRIM program and photocarrier radiometry(PCR)are employed to monitor the boron implantation in industrial-grade silicon in an ultra-low implantation energy range from 0.5 keV to 5 keV. The differential PCR technique, which is improved by greatly shortening the measurement time through the simplification of reference sample, is used to investigate the effects of implantation energy on the frequency behavior of the PCR signal for ultra-shallow junction. The transport parameters and thickness of shallow junction, extracted via multi-parameter fitting the dependence of differential PCR signal on modulation frequency to the corresponding theoretical model, well explain the energy dependence of PCR signal and further quantitatively characterize the recovery degree of structure damage induced by ion implantation and the electrical activation degree of impurities. The monitoring of nmlevel thickness and electronic properties exhibits high sensitivity and apparent monotonicity over the industrially relevant implantation energy range. The depth profiles of implantation boron in silicon with the typical electrical damage threshold(YED) of 5.3×10^(15)cm^(-3) are evaluated by the SRIM program, and the determined thickness values are consistent well with those extracted by the differential PCR. It is demonstrated that the SRIM and the PCR are both effective tools to characterize ultra-low energy ion implantation in silicon. 展开更多
关键词 ultra-low energy ion implantation differential nonlinear photocarrier radiometry junction depth electronic transport parameters
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Earthquake-Generating Structure During the Period of the 1992 Sichuan Lima Earthquake Sequence
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作者 Zhao Zhu and Chen NongSeismological Bureau of Sichuan Province,Chengdu 610041,China 《Earthquake Research in China》 1996年第3期63-74,共12页
In this paper,a test or alternative scheme for studying large earthquake sequences through the study of small earthquake sequences is suggested,and a small earthquake sequence,the Lima earthquake sequence for which an... In this paper,a test or alternative scheme for studying large earthquake sequences through the study of small earthquake sequences is suggested,and a small earthquake sequence,the Lima earthquake sequence for which analogue records have been turned into digital data,is used here.In order to provide the deep construction background and the spatial distribution of structure for generating earthquakes,the P-wave and S-wave layered velocity models in this area are obtained by using mine explosion and earthquake observed records; then,the hypocenter locations and focal depths of the Lima earthquake sequence are determined adopting the velocity models given above and using a location method with numerical properties for a microseismic monitoring network(Zhao et al.,1994)and a new method for determining focal depth from data of a local seismographic network(Zhao,1992); finally,based on this,the variation of quality factor Q of the crustal medium during the period of the sequence is estimated.The obtained 展开更多
关键词 EARTHQUAKE sequence FOCAL location FOCAL depth Quality factor Q
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Temporal and Spatial Variations of Accommodation and Sediment Accumulation during Transgressive to Highstand Stages as Reconstructed from a Latest Pleistocene to Holocene Sequence in the Intra-Arc Osaka Basin, Japan
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作者 Fujio Masuda Natsumi Itomoto 《Open Journal of Geology》 2015年第1期28-37,共10页
Temporal and spatial variations in accommodation (i.e., paleo-water depth) and sediment accumulation (amount of deposition) in the intra-arc Osaka Basin, Japan, were reconstructed from the post-glacial transgression t... Temporal and spatial variations in accommodation (i.e., paleo-water depth) and sediment accumulation (amount of deposition) in the intra-arc Osaka Basin, Japan, were reconstructed from the post-glacial transgression through the sea-level highstand, a total of 9000 years. At the beginning of the marine transgressive stage (about 11,000 cal y BP), paleo-water depths were shallow and the sediment accumulation was large. The area occupied by Osaka Bay gradually extended and sediment deposition decreased from 11,000 to 6000 cal y BP. During the period of maximum transgression (6000 - 5000 cal y BP), an inner bay, Kawachi Bay with a water depth of 5 - 10 m, was expanded in the inland eastern Osaka area, and paleo-water depths reached a maximum and depositional rates reached a minimum. During the subsequent highstand and small regression (about 5000 cal y BP to the present), however, deposition increased rapidly as a result of river delta and shoreline progradations. Regional differences were observed in accommodation and accumulation between the outer bay area and the inner bay area. During both the transgressive and regressive stages, deposition decreased in the inner bay area. In contrast, in the outer bay area and in the basin overall, deposition was high during the first part of the transgressive stage but it decreased during the maximum transgression, before reaching a maximum during the subsequent highstand and regression. During the regressive stage, fluvial delta progradation led to the formation of a thick sequence of delta body sediments. Sediment accumulation was 30% - 40% higher during the regressive stage than that during the transgressive stage. 展开更多
关键词 ACCOMMODATION HOLOCENE Osaka Plain Paleo-depths Sediment Accumulation sequencE STRATIGRAPHY
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基于价值评估的废旧产品拆卸序列与拆卸深度决策
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作者 张华 殷俊鸿 +3 位作者 鄢威 马峰 江志刚 朱硕 《组合机床与自动化加工技术》 北大核心 2025年第1期143-149,共7页
为解决拆卸序列规划(disassembly sequence planning, DSP)中存在的复杂模型构建难题、组合爆炸以及拆解深度决策不合理等问题,提出了一种基于知识图谱属性图模块化的改进方法实现废旧产品拆卸信息的获取,并提出了一种基于剩余回收效益... 为解决拆卸序列规划(disassembly sequence planning, DSP)中存在的复杂模型构建难题、组合爆炸以及拆解深度决策不合理等问题,提出了一种基于知识图谱属性图模块化的改进方法实现废旧产品拆卸信息的获取,并提出了一种基于剩余回收效益评估的拆解序列与拆解深度综合决策方法。首先,通过分析废旧产品的拆卸特征以及产品内部零部件的信息和拆卸联接关系,构建支持拆解的模块化属性图模型;其次,采用组合赋权及改进的TOPSIS灰色关联分析法构建了零件回收综合评价模型的多属性决策模型,对产品综合内部零部件剩余回收效益进行排序;再次,提出了基于改进遗传-粒子群算法的完全拆解序列生成方法,并结合剩余回收效益值进行废旧产品零件的拆解深度决策。以废旧汽车动力电池包为例对上述模型和方法进行了验证,证明了该方法的可行性和高效性。 展开更多
关键词 废旧产品 知识图属性图模型 零件回收综合评价 拆卸序列优化 拆卸深度决策
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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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松辽盆地国际大陆科学钻探松科2井基底变质岩研究
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作者 王璞珺 高传承 +10 位作者 高有峰 杨卓龙 唐鑫 郑常青 刘硕 刘海波 李宏浩 高翔 高远 王成善 万晓樵 《地学前缘》 北大核心 2025年第5期38-51,共14页
松辽盆地国际大陆科学钻探工程及相关研究历时18年(2005—2023年),实施“三井四孔”技术方案,完成总钻探进尺14455.06 m,总取心进尺8528.19 m,收获岩心总长度8261.67 m,总取心率96.87%。这使得松辽盆地成为全球首例钻穿整个沉积盖层和... 松辽盆地国际大陆科学钻探工程及相关研究历时18年(2005—2023年),实施“三井四孔”技术方案,完成总钻探进尺14455.06 m,总取心进尺8528.19 m,收获岩心总长度8261.67 m,总取心率96.87%。这使得松辽盆地成为全球首例钻穿整个沉积盖层和盆地基底顶部构造层并获取连续完整岩心的含油气盆地。这些岩心和测井录井及地震资料为全球和区域重大地质事件研究提供了全球最高精度的地质档案,从而大大提升了松辽盆地研究的国际学术地位。然而,与这项工程相关的三个基本技术问题至今还没有得到妥善解决。一是三井四孔的取心层位和取心率还没有准确统计结果和相关报道;二是松科2井的完钻井深及其相关报道尚不够清晰;三是松科2井最后100 m到底钻遇到了什么?相关的岩石类型、地层序列和测井资料,迄今未见客观翔实的科学报道。作为松辽盆地国际大陆科学钻探核心工作组之一的地质研究团队,作者拟通过本文重点回答上述3个问题。我们基于松辽盆地国际大陆科学钻探松科2井的全取心资料,通过岩石类型及变质变形特征研究,在井深7000~7108.88 m的中泥盆统基底序列中识别出一套动力变质岩,详细研究和报道了该套变质杂岩的岩性组合与地层序列。另外,关于松科2井的完钻井深和三井四孔的钻探取心数据在本文中也给出了翔实的统计结果。 展开更多
关键词 松辽盆地 国际大陆科学钻探 松科2井 完钻井深7108 m 变质杂岩 中泥盆统基底
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利用基因组测序技术鉴定家蚕转基因位点方法的建立
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作者 周昂 蒋晶晶 +4 位作者 左伟东 陈欣 童晓玲 代方银 李春林 《西南大学学报(自然科学版)》 北大核心 2025年第4期113-122,共10页
建立一种基于基因组测序技术高效鉴定家蚕转基因插入位点的方法,并分析测序深度对位点鉴定准确性的影响,从而为家蚕及其他物种利用基因组测序技术开展低成本、高通量的转基因位点鉴定提供参考。首先,采集两份家蚕转基因材料的蛹,进行全... 建立一种基于基因组测序技术高效鉴定家蚕转基因插入位点的方法,并分析测序深度对位点鉴定准确性的影响,从而为家蚕及其他物种利用基因组测序技术开展低成本、高通量的转基因位点鉴定提供参考。首先,采集两份家蚕转基因材料的蛹,进行全基因组测序,并经过质量控制筛选出高质量的测序后读段(reads)。以载体序列和家蚕基因组为参考,经两轮比对分析,得到覆盖基因组和载体的目标reads。利用目标reads上的基因组序列在家蚕泛基因组数据库中进行比对分析,进而获得插入位点的具体位置。随后,运用Seqtk软件对数据进行抽样,分析不同测序深度对位点鉴定准确性的影响。两份材料的基因组测序数据分别为9.76 G和11.18 G,质控后读段(clean reads)数量分别为32639026和37394695,测序深度约为20×。序列比对分析和聚合酶链式反应(PCR)实验验证结果显示:TransGene_1的插入位点位于1号染色体1899494 bp与1899495 bp之间;TransGene_2的插入位点位于21号染色体959510 bp与959515 bp之间,且插入位点均处于基因间区。利用两份转基因材料的基因组测序数据进行不同测序深度的模拟分析,发现转基因材料TransGene_1在测序深度为6×时就能够得到覆盖两侧断点的reads,实现精确定位,而TransGene_2则需要测序深度达到10×及以上才能实现精确定位。 展开更多
关键词 家蚕 转基因插入位点 基因组测序 测序深度 转基因鉴定
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2023年云南芒市M_(S)5.0地震震源深度测定及其发震机理探讨
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作者 顾慧冬 姜金钟 +5 位作者 李姣 常玉巧 杨跃文 王光明 张帅 姚远 《地震学报》 北大核心 2025年第5期611-631,共21页
基于云南地震台网近震波形资料和两种区域速度模型,利用CAP方法反演了2023年12月2日云南省芒市地震序列中M_(S)5.0主震和4次M_(L)≥3.5余震的震源机制解和震源深度,然后采用sPL深度震相进一步测定了震源深度,最后综合震源深度、地震烈... 基于云南地震台网近震波形资料和两种区域速度模型,利用CAP方法反演了2023年12月2日云南省芒市地震序列中M_(S)5.0主震和4次M_(L)≥3.5余震的震源机制解和震源深度,然后采用sPL深度震相进一步测定了震源深度,最后综合震源深度、地震烈度和地震重定位等结果探讨了此次芒市地震的发震机理。结果表明:芒市M_(S)5.0主震为走滑型地震兼具正断分量,最佳双力偶机制解节面Ⅰ为走向89°,倾角78°,滑动角−20°,节面Ⅱ为走向183°,倾角70°,滑动角−167°;4次M_(L)≥3.5余震为走滑兼逆冲型或逆冲型地震,其最佳双力偶机制解均存在NE走向节面,该节面的走向、倾角、滑动角平均值约为247°,65°,26°,与芒市地震序列震中分布走向和地震烈度长轴走向比较一致;M_(S)5.0主震与4次M_(L)≥3.5余震的震源深度均在5—7 km范围内,说明震区内地震主要发生在上地壳浅部。鉴于此次主震发生在水库库区且地震时库区处于高水位、震源分布较浅且主余震震源机制解明显不一致,本研究初步推测库区流体作用可能促进了此次地震的发生,且主震破裂引起局部应力调整所导致的邻近断层滑动使得本次地震序列余震的优势分布方向沿NE向展布。 展开更多
关键词 芒市地震序列 震源深度 震源机制解 sPL 深度震相 发震机理
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基于BSA-seq技术的块茎芽眼深度QTL定位分析
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作者 邵顺伟 陈卓 +9 位作者 兰振东 蔡兴奎 邹华芬 李晨曦 唐景华 朱熙 张彧 董建科 金辉 宋波涛 《作物学报》 北大核心 2025年第7期1725-1735,共11页
芽眼深度是马铃薯块茎的重要性状之一,对马铃薯的外观品质及加工适宜性具有重要影响。为挖掘控制马铃薯芽眼深度的数量性状位点,本研究以四倍体深芽眼品种“华薯12”为母本、浅芽眼高代品系“天2002-4-5”为父本,杂交获得F_(1)代分离群... 芽眼深度是马铃薯块茎的重要性状之一,对马铃薯的外观品质及加工适宜性具有重要影响。为挖掘控制马铃薯芽眼深度的数量性状位点,本研究以四倍体深芽眼品种“华薯12”为母本、浅芽眼高代品系“天2002-4-5”为父本,杂交获得F_(1)代分离群体,共255份无性系。基于连续2年田间表型观测数据,分别选取20个深芽眼和20个浅芽眼个体构建混合池,利用BSA-seq技术进行芽眼深度相关性状的QTL定位,并结合传统QTL定位方法,采用完备区间作图法构建遗传连锁图谱,成功定位到2个与芽眼深度相关的QTL位点。2年表型相关性分析结果表明,马铃薯块茎芽眼深度主要受遗传因素的控制。10号染色体上qEyd10.1位点的LOD值为4.96,表型贡献率为14.49%;3号染色体上qEyd3.1位点的LOD值为3.29,表型贡献率为10.18%。其中, qEyd3.1与此前报道的芽眼深度调控位点一致,而qEyd10.1为新发现的QTL。2个位点的加性效应均为负值,表明降低芽眼深度的等位基因来源于浅芽眼亲本“天2002-4-5”。通过对定位区间内候选基因注释结合芽眼深浅材料基因结构变异分析,推测Soltu.DM.10G029390.1、Soltu.DM.03G036540.1、Soltu.DM.03G036140.1和Soltu.DM.03G036580.1可能为与芽眼深度相关的候选基因。本研究通过BSA-seq与传统QTL定位相结合的方式,快速完成了同源四倍体马铃薯中芽眼深度这一数量性状的调控位点定位工作,并初步确定了4个候选基因,为进一步完成芽眼深度调控基因的克隆及其遗传机制解析奠定了重要基础,也为培育具有浅芽眼块茎的四倍体马铃薯新品种提供了参考。 展开更多
关键词 马铃薯 芽眼深度 QTL定位 BSA-seq 遗传连锁图谱
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Impact of the next-generation sequencing data depth on various biological result inferences 被引量:3
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作者 HOU Rui YANG ZhenXing +1 位作者 LI MingHui XIAO HuaSheng 《Science China(Life Sciences)》 SCIE CAS 2013年第2期104-109,共6页
Next-generation sequencing(NGS) technologies have revolutionized the field of genomics and provided unprecedented opportunities for high-throughput analysis at the levels of genomics,transcriptomics and epigenetics.Ho... Next-generation sequencing(NGS) technologies have revolutionized the field of genomics and provided unprecedented opportunities for high-throughput analysis at the levels of genomics,transcriptomics and epigenetics.However,the cost of NGS is still prohibitive for many laboratories.It is imperative to address the trade-off between the sequencing depth and cost.In this review,we will discuss the effects of sequencing depth on the detection of genes,quantification of gene expression and discovering of gene structural variants.This will provide readers information on choosing appropriate sequencing depth that best meet the needs of their particular project. 展开更多
关键词 next-generation sequencing depth gene discovery gene expression structure variation next-generation sequencing depth gene discovery gene expression structure variation
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基于改进注意力机制的语音合成方法
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作者 陈若飞 王景成 +1 位作者 李继超 张彬彬 《计算机仿真》 2025年第2期193-197,共5页
针对基于Local Sensitive Attention的语音合成存在长句合成鲁棒性差,对齐效果差,信息丢失等问题,提出三点改进措施:首先在使用深度分离卷积代替标准卷积,既减少模型参数又增加了卷积层的深度,从而提高了卷积操作的特征表达能力。其次缩... 针对基于Local Sensitive Attention的语音合成存在长句合成鲁棒性差,对齐效果差,信息丢失等问题,提出三点改进措施:首先在使用深度分离卷积代替标准卷积,既减少模型参数又增加了卷积层的深度,从而提高了卷积操作的特征表达能力。其次缩小Energies数值的范围,将其与缩小因子α相乘可以将其范围缩小,这样可以避免在后面Softmax函数处理中出现数值过大的情况,提高模型稳定性和对于长序列的对齐能力。最后,使用两层BIGRU替换单层BILSTM,能更好提取上下文语义加强特征信息进而减少信息丢失。提高语音合成质量。实验结果表明,改进后的模型相比于原模型在长句语音合成时良好的对齐功能,有较好的鲁棒性且在提升原始模型的音色质量的前提下,训练损失降低了7%。 展开更多
关键词 注意力机制 语音合成 深度分离卷积 长序列
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多尺度代价聚合的多聚焦图像3维形貌重建框架 被引量:2
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作者 闫涛 尚起慧 +3 位作者 吴鹏 张江峰 钱宇华 陈斌 《计算机研究与发展》 北大核心 2025年第7期1771-1785,共15页
多聚焦图像3维形貌重建旨在利用不同聚焦水平的图像序列恢复场景的3维结构信息.现有的3维形貌重建方法大多从单一尺度对图像序列的聚焦水平进行评价,通过引入正则化或后处理方法引导重建过程,由于深度信息选择空间的局限性往往导致重建... 多聚焦图像3维形貌重建旨在利用不同聚焦水平的图像序列恢复场景的3维结构信息.现有的3维形貌重建方法大多从单一尺度对图像序列的聚焦水平进行评价,通过引入正则化或后处理方法引导重建过程,由于深度信息选择空间的局限性往往导致重建结果无法有效收敛.针对上述问题,提出一种多尺度代价聚合的多聚焦图像3维形貌重建框架(multi-scale cost aggregation framework for 3D shape reconstruction from multi-focus images,MSCAS),该框架首先引入非降采样的多尺度变换增加输入图像序列的深度信息选择空间,然后联合尺度内序列关联与尺度间信息约束进行代价聚合,通过这种扩张-聚合模式实现了场景深度表征信息的倍增与跨尺度和跨序列表征信息的有效融合.作为一种通用框架,MSCAS框架可实现已有模型设计类方法和深度学习类方法的嵌入进而实现性能提升.实验结果表明:MSCAS框架在嵌入模型设计类SFF方法后4组数据集中的均方根误差(root mean squared error,RMSE)平均下降14.91个百分点,结构相似度(structural similarity index measure,SSIM)平均提升56.69个百分点,嵌入深度学习类SFF方法后4组数据集中的RMSE平均下降1.55个百分点,SSIM平均提升1.61个百分点.验证了MSCAS框架的有效性和通用性. 展开更多
关键词 多尺度代价聚合 深度估计 聚焦测量 多聚焦图像序列 3维形貌重建
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In-depth cDNA Library Sequencing Provides Quantitative Gene Expression Profiling in Cancer Biomarker Discovery
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作者 Wanling Yang Dingge Ying Yu-Lung Lau 《Genomics, Proteomics & Bioinformatics》 SCIE CAS CSCD 2009年第1期1-12,共12页
Quantitative gene expression analysis plays an important role in identifying differentially expressed genes in various pathological states, gene expression regulation and co-regulation, shedding light on gene function... Quantitative gene expression analysis plays an important role in identifying differentially expressed genes in various pathological states, gene expression regulation and co-regulation, shedding light on gene functions. Although microarray is widely used as a powerful tool in this regard, it is suboptimal quantitatively and unable to detect unknown gene variants. Here we demonstrated effective detection of differential expression and co-regulation of certain genes by expressed sequence tag analysis using a selected subset of cDNA libraries. We discussed the issues of sequencing depth and library preparation, and propose that increased sequencing depth and improved preparation procedures may allow detection of many expression features for less abundant gene variants. With the reduction of sequencing cost and the emerging of new generation sequencing technology, in-depth sequencing of cDNA pools or libraries may represent a better and powerful tool in gene expression profiling and cancer biomarker detection. We also propose using sequence-specific subtraction to remove hundreds of the most abundant housekeeping genes to increase sequencing depth without affecting relative expression ratio of other genes, as transcripts from as few as 300 most abundantly expressed genes constitute about 20% of the total transcriptome. In-depth sequencing also represents a unique advantage of detecting unknown forms of transcripts, such as alternative splicing variants, fusion genes, and regulatory RNAs, as well as detecting mutations and polymorphisms that may play important roles in disease pathogenesis. 展开更多
关键词 cDNA sequencing sequencing depth expressed sequence tag sequence-specific subtraction biomarker mutation detection
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东昆仑东段那更康切尔地区银多金属矿床原生晕特征及深部预测
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作者 于小亮 王成勇 +6 位作者 李杰 马财 董基恩 李华 李向军 康波 魏小林 《西北地质》 北大核心 2025年第3期221-235,共15页
那更康切尔地区位于东昆仑造山带东段的沟里金矿田,为青海省首次发现的一处大型独立银矿床。随着银矿找矿工作向深部探索,开展钻孔原生晕预测深部找矿是目前较为直观且有效的方法。本研究通过系统采集那更康切尔银矿Ⅺ矿带0勘探线7个钻... 那更康切尔地区位于东昆仑造山带东段的沟里金矿田,为青海省首次发现的一处大型独立银矿床。随着银矿找矿工作向深部探索,开展钻孔原生晕预测深部找矿是目前较为直观且有效的方法。本研究通过系统采集那更康切尔银矿Ⅺ矿带0勘探线7个钻孔919件样品进行地球化学测试,分析了Au、Ag、Cu、Pb、Zn、W、Sn、Mo、As、Sb、Hg、F、Mn、Bi、Co等15种元素。用聚类分析方法研究了元素组合特征,运用格里戈良法研究了原生晕分带特征。结果表明,矿体自上而下原生晕轴向分带序列为Au→Hg→Ag→Mo→Mn→Sn→Sb→As→Pb→Zn→W→Bi→Cu→F→Co,总结了矿床异常元素的分带规律,确定成矿近矿晕元素为Ag、Pb、Zn、Au、Sb、Sn、Cu,前缘晕元素为Hg、As、(F),尾晕元素为Mo、Co、Mn、(Bi)、(W)。且存在前缘晕、近矿晕和尾晕元素相叠加的特征,以及异常向深部延伸未显示歼灭的现象,说明矿体深部沿轴向仍有延伸,结合物化探特征,并与区域矿床对比研究分析认为,Ⅺ矿带北延部分矿体向深部仍有延伸,深部找矿潜力较大。 展开更多
关键词 那更康切尔银矿 原生晕 元素组合特征 轴向分带序列 深部预测
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