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高光谱数据的波段序结构分析与应用研究 被引量:11
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作者 张远飞 吴德文 +2 位作者 张艮中 朱谷昌 李红 《国土资源遥感》 CSCD 2010年第1期30-38,共9页
把高光谱数据近似于连续的细分波段作为波段序列数据,由此提出波段序结构分析技术,主要包括波段序列直方图、左(右)偏度参量分析、相关(似)矩阵分析和回归偏度分析等。通过对波段序结构分析技术在高光谱数据的统计特征分析与数据质量评... 把高光谱数据近似于连续的细分波段作为波段序列数据,由此提出波段序结构分析技术,主要包括波段序列直方图、左(右)偏度参量分析、相关(似)矩阵分析和回归偏度分析等。通过对波段序结构分析技术在高光谱数据的统计特征分析与数据质量评价、"蚀变异常"信息潜在性评价与特征波段选择及矿物蚀变信息提取等几个方面的应用研究与实践,阐述了这一技术思想的科学性与实用价值。 展开更多
关键词 高光谱数据 波段序结构分析 蚀变信息提取
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序结构分析在画法几何教学中的应用 被引量:1
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作者 葛仕恩 《沙洲职业工学院学报》 2001年第2期70-72,共3页
从机械制图的本质出发,在相似原理的指导下,应用序结构分析的手段,对画法几何的逻辑体系及系统功能进行分析,提出了新的教学体系,指出了画法几何对于机械制图的基础性作用。
关键词 相似原理 序结构分析 机械制图 画法几何 教学 应用 简单空间 三面投影系 线 教学体系
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胜坨油田胜一区沙二段上部高分辨率层序结构分析和叠加样式研究 被引量:12
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作者 李振泉 郑荣才 《石油勘探与开发》 SCIE EI CAS CSCD 北大核心 2003年第4期47-50,共4页
胜一区位于渤海湾盆地济阳坳陷胜坨油田的西部 ,沙二段上部油层主要属低弯度辫状河三角洲平原亚相沉积。基于基准面旋回理论的高分辨率层序地层学理论 ,把胜一区沙二段上部 1~ 3砂层组划分为一个中期旋回层序 ,5个短期和14~ 16个超短... 胜一区位于渤海湾盆地济阳坳陷胜坨油田的西部 ,沙二段上部油层主要属低弯度辫状河三角洲平原亚相沉积。基于基准面旋回理论的高分辨率层序地层学理论 ,把胜一区沙二段上部 1~ 3砂层组划分为一个中期旋回层序 ,5个短期和14~ 16个超短期旋回层序。在层序格架的控制下 ,建立了超短期、短期和中期旋回层序结构的叠加样式 ;按岩性、岩相组合特征及沉积演化序列 ,超短期旋回层序、短期旋回层序分为向上“变深”非对称型和对称型 2种基本结构类型 ;中期旋回层序结构为以上升半旋回为主的不完全对称型。图 2参 展开更多
关键词 胜坨油田 序结构分析 叠加样式
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遥感蚀变信息多层次分离技术模型与应用研究 被引量:19
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作者 张远飞 吴德文 +3 位作者 袁继明 朱谷昌 杨自安 胡波 《国土资源遥感》 CSCD 2011年第4期6-13,共8页
根据自然物质系统具有层次结构的特性,在多年实践的基础上,对遥感蚀变信息提取问题提出了多层次分离技术模型。在这个技术模型框架下,首先讨论了遥感蚀变信息提取这一复杂研究对象的简化问题;然后系统地阐述了该技术模型的基本原理和模... 根据自然物质系统具有层次结构的特性,在多年实践的基础上,对遥感蚀变信息提取问题提出了多层次分离技术模型。在这个技术模型框架下,首先讨论了遥感蚀变信息提取这一复杂研究对象的简化问题;然后系统地阐述了该技术模型的基本原理和模型结构,以及该模型框架下的主要技术体系。应用实例分析结果表明,该模型所提出的技术思想不仅简化了遥感蚀变信息提取问题的复杂性,而且在实际应用中显现出良好的实用性。 展开更多
关键词 遥感蚀变信息提取 多层次分离技术 技术体系 空间结构分析 序结构分析
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Feature extraction and damage alarming using time series analysis 被引量:4
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作者 刘毅 李爱群 +1 位作者 费庆国 丁幼亮 《Journal of Southeast University(English Edition)》 EI CAS 2007年第1期86-91,共6页
Aiming at the problem of on-line damage diagnosis in structural health monitoring (SHM), an algorithm of feature extraction and damage alarming based on auto-regressive moving-average (ARMA) time series analysis i... Aiming at the problem of on-line damage diagnosis in structural health monitoring (SHM), an algorithm of feature extraction and damage alarming based on auto-regressive moving-average (ARMA) time series analysis is presented. The monitoring data were first modeled as ARMA models, while a principalcomponent matrix derived from the AR coefficients of these models was utilized to establish the Mahalanobisdistance criterion functions. Then, a new damage-sensitive feature index DDSF is proposed. A hypothesis test involving the t-test method is further applied to obtain a decision of damage alarming as the mean value of DDSF had significantly changed after damage. The numerical results of a three-span-girder model shows that the defined index is sensitive to subtle structural damage, and the proposed algorithm can be applied to the on-line damage alarming in SHM. 展开更多
关键词 feature extraction damage alarming time series analysis structural health monitoring
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Complete Sequence and Gene Organization of the Mitochondrial Genome of Tokay (Gekko gecko) 被引量:8
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作者 韩德民 周开亚 《Zoological Research》 CAS CSCD 北大核心 2005年第2期123-128,共6页
Long-PCR amplification, clone and primer-walking sequencing methods were employed in determine the complete sequence of mitochondrial genome of tokay (Gekko gecko). The genome is 16 435 bp in size, contains 13 protein... Long-PCR amplification, clone and primer-walking sequencing methods were employed in determine the complete sequence of mitochondrial genome of tokay (Gekko gecko). The genome is 16 435 bp in size, contains 13 protein-coding, 2 ribosomal and 22 transfer RNA genes. The mt genome of Gekko is similar to most of the vertebrates in gene components, order, orientation, tRNA structures, low percentage of guanine and high percentage of thymine, and skews of base GC and AT. Base A was preferred at third codon positions for protein genes is similar to amphibians and fishes rather than amnion vertebrates. The standard stop codes (TAA) present only in three protein genes, less than those of most vertebrates. Transfer RNA genes range in length from 63 to 76 nt, their planar structure present characteristic clover leaf, except for tRNA-Cys and tRNA-Ser (AGY) because of lacking the D arm. 展开更多
关键词 Gekko gecko SQUAMATE Complete sequence of mitochondrial genome Gene organization
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A Generalization of Caristi Fixed Point Theorem 被引量:5
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作者 孙经先 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第1期72-75,共4页
Let X be a metric space with an ordering structure,A: X→X is a operator and x≤Ax for any x∈X. In this paper we prove a new fixed point theorem, which generalizes famous caristi fixed point theorem.
关键词 metric space partially ordred set fixed point theorem
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Structural Variation Analysis of Mutated Nannochloropsis oceanica Caused by Zeocin Through Genome Re-Sequencing 被引量:3
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作者 LIN Genmei ZHANG Zhongyi +2 位作者 GUO Li DING Haiyan YANG Guanpin 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第5期1225-1230,共6页
Zeocin can cause double strand breaks of DNA and thus may be employed as a mutagen. In this study, two strains of Nannochloropsis oceanica, the wild and the Zeocin-tolerant strains, were re-sequenced to verify such fu... Zeocin can cause double strand breaks of DNA and thus may be employed as a mutagen. In this study, two strains of Nannochloropsis oceanica, the wild and the Zeocin-tolerant strains, were re-sequenced to verify such function of Zeocin, The results showed that Zeocin can mutate the N. oceanica genome and cause the structural variation. Zeocin either swept away or selected the alleles of genes functioning in ubiquitin-mediated proteolysis, alpha-linolenic acid metabolism, ascorbate and aldarate metabolism, ribosome biogenesis, and circadian rhythm, indicating that N. oceanica may have adjusted its metabolic performances for protein, carbohydrate, and lipid, and changed its ribosome biosynthesis and living rhythm to survive in Zeocin containing medium. In addition, Zeocin caused mutation may have influenced the expression of a set of tanscription factors. It was concluded that Zeocin effectively caused the structural variation of the genome of N. oceanica, and forced the microalgae to select out the alleles of a set of genes around these variations in order to adapt to Zeocin containing medium. Further studies on the genetic basis of the phenotypic adaptation of this haploid and asexual microalga and the application of Zeocin to its genetic improvement are very important. 展开更多
关键词 Nannochloropsis oceanica Zeocin MUTATION genome re-sequencing structural variation
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In-place structural strength and fatigue analysis for floating platform topsides
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作者 Chen Lizhong 《Engineering Sciences》 EI 2013年第4期24-34,共11页
This paper presents some insights on the state-of-the-art practice that has been utilized recently in the inplace structural strength and fatigue analysis for topsides on deepwater floating platforms such as tension l... This paper presents some insights on the state-of-the-art practice that has been utilized recently in the inplace structural strength and fatigue analysis for topsides on deepwater floating platforms such as tension leg plat-form (TLP) and semi-submersibles. Emphases are put on analysis software,geometric and mass modeling,hydro-dynamic loading and its mapping,and analysis procedures. In addition,for the in-place analysis using structure analysis computer system (SACS),the procedure of Visual Basic for Application (VBA) is developed to map AQWA-LINE hydrodynamic loading to the SACS integrated hull/topsides model;for the in-place analysis using structure engineering system analysis model (SESAM),many computer aided applications are made to aid the post-processing. These applications have been used in structural analyses for a few TLP and semi-submersible plat-form topsides,and are briefly introduced in this paper. 展开更多
关键词 topsides TLP SEMI-SUBMERSIBLE in-place structural analysis hydrodynamic loading SACS SESAM
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Research on numerical welding experiment of a thick spherical shell structure
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作者 刘向东 姚熊亮 庞福振 《Journal of Marine Science and Application》 2008年第2期69-76,共8页
In this paper, in order to predict the residual deformation of thick spherical structure, a welding program is compiled in APDL language based on Ansys and a numerical welding experiment of a welding example is carrie... In this paper, in order to predict the residual deformation of thick spherical structure, a welding program is compiled in APDL language based on Ansys and a numerical welding experiment of a welding example is carried out. The temperature field of welding was simulated firstly, then a thermal-structure coupling analysis was carried out, and at last the residual stress and deformation after welding were got. After that, the numerical experiment result was compared with physical experiment one. The comparative analysis shows that the numerical simulation fits well with physical experiment. On the basis of that, a three-dimensional numerical experiment of a thick spherical shell structure was carried out to get the changing rule of stress and deformation of a thick spherical shell structure during welding. The research is of great value to the prediction of residual deformation and high precision machining. 展开更多
关键词 welding program thermal-structure coupling analysis residual stress residual deformation thick spherical shell structure
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Seismic analysis of a long-span continuous steel truss-arch bridge across the Yangtze River
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作者 XIA Chao-yi LEI Jun-qing +1 位作者 XIA He PI Yong-lin 《Journal of Civil Engineering and Architecture》 2009年第5期1-8,共8页
In this paper, an FEM (Finite Element Method) model is established for the main span of the bridge, with the main box arch and suspender members modeled by beam elements, truss members by truss elements, and the ort... In this paper, an FEM (Finite Element Method) model is established for the main span of the bridge, with the main box arch and suspender members modeled by beam elements, truss members by truss elements, and the orthotropic steel deck by plate elements. The natural frequencies and mode shapes are acquired by the eigen-parameter analysis. By input of a typical earthquake excitation to the bridge system, the dynamic responses of the bridge, including the displacement and accelerations of the main joints of the structure, and the seismic forces and stresses of the key members, are calculated by the structural analysis program, based on which the main laws of the seismic responses of the bridge are summarized, and the safety of the structure is evaluated. 展开更多
关键词 FEM main span of the bridge natural frequencies the dynamic responses
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Innovative Applications of Post-Tension for Restoration and Rehabilitation of Bridges and Structures--Case Studies in India
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作者 Ramesh Kommajosyula Narapraju Venkat Ramana Rao 《Journal of Civil Engineering and Architecture》 2014年第7期869-880,共12页
This paper deals with new and innovative case studies of application of post-tensioning for restoration of structures for buildings, bridges and rock stabilization in India. In earlier situations for these types of ca... This paper deals with new and innovative case studies of application of post-tensioning for restoration of structures for buildings, bridges and rock stabilization in India. In earlier situations for these types of cases conventional method of repair and rehabilitation has been used. These innovative approaches for restoration have led to enormous saving of cost and time. The advantages of post tensioning are well known in the civil industry and are being used for the last 40 to 50 years. Post tensioning is one of the best methods to induce stresses in the concrete before application of live load and this technique can also be widely used for restoration and rehabilitation of structures. Unlike the use of post-tensioning in new structures there are no definite methods or codes for application in restoration and rehabilitation of structures. For restoration and rehabilitation of structures, PT (post tensioned) technique can be applied in combination with other techniques and materials available. Bridge lifting is a tricky and risky job especially when the superstructure is displaced appreciably by a natural calamity, etc.. Not only the present state of structure needs proper study before commencement of restoration and rehabilitation but also calls for careful execution. This paper deals with case studies of innovative applications of post tensioning in restoration and rehabilitation of structures and restoration of bridge structure in Andaman & Nicobar Island, India affected by Sumatra quake. 展开更多
关键词 RESTORATION REHABILITATION structures external post tensioning rock stabilization.
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Progressive failure analysis of composite structure based on micro- and macro-mechanics models 被引量:1
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作者 孙志刚 阮绍明 +1 位作者 陈磊 宋迎东 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期2980-2988,共9页
Based on parameter design language, a program of progressive failure analysis in composite structures is proposed. In this program, the relationship between macro- and micro-mechanics is established and the macro stre... Based on parameter design language, a program of progressive failure analysis in composite structures is proposed. In this program, the relationship between macro- and micro-mechanics is established and the macro stress distribution of the composite structure is calculated by commercial finite element software. According to the macro-stress, the damaged point is found and the micro-stress distribution of representative volume element is calculated by finite-volume direct averaging micromechanics(FVDAM). Compared with the results calculated by failure criterion based on macro-stress field(the maximum stress criteria and Hashin criteria) and micro-stress field(Huang model), it is proven that the failure analysis based on macro- and micro-mechanics model is feasible and efficient. 展开更多
关键词 composite progressive analysis finite-volume direct averaging micromechanics (FVDAM) failure criteria
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RNA-Seq analysis of yak ovary: improving yak gene structure information and mining reproduction-related genes 被引量:26
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作者 LAN DaoLiang XIONG XianRong +5 位作者 WEI YanLi XU Tong ZHONG JinCheng ZHI XiangDong WANG Yong LI Jian 《Science China(Life Sciences)》 SCIE CAS 2014年第9期925-935,共11页
RNA-Seq, a high-throughput (HT) sequencing technique, has been used effectively in large-scale transcriptomic studies, and is particularly useful for improving gene structure information and mining of new genes. In ... RNA-Seq, a high-throughput (HT) sequencing technique, has been used effectively in large-scale transcriptomic studies, and is particularly useful for improving gene structure information and mining of new genes. In this study, RNA-Seq HT technology was employed to analyze the transcriptome of yak ovary. After lllurrlina-Solexa deep sequencing, 26826516 clean reads with a total of 4828772880 bp were obtained from the ovary library. Alignment analysis showed that 16992 yak genes mapped to the yak genome and 3734 of these genes were involved in alternative splicing. Gene structure refinement analysis showed that 7340 genes that were annotated in the yak genome could be extended at the 5' or 3' ends based on the alignments been the transcripts and the genome sequence. Novel transcript prediction analysis identified 6321 new transcripts with lengths ranging from 180 to 14884 bp, and 2267 of them were predicted to code proteins. BLAST analysis of the new transcripts showed that 1200-4933 mapped to the non-redundant (nr), nucleotide (nt) and/or SwissProt sequence databases. Comparative statistical analysis of the new mapped transcripts showed that the majority of them were similar to genes in Bos taurus (41.4%), Bos grunniens mutus (33.0%), Ovis aries (6.3%), Homo sapiens (2.8%), Mus musculus (1.6%) and other species. Functional analy- sis showed that these expressed genes were involved in various Gene Ontology (GO) categories and Kyoto Encyclopedia of Genes and Genomes pathways. GO analysis of the new transcripts found that the largest proportion of them was associated with reproduction. The results of this study will provide a basis for describing the normal transcriptome map of yak ovary and for future studies on yak breeding performance. Moreover, the results confirmed that RNA-Seq HT technology is highly ad- vantageous in improving gene structure information and mining of new genes, as well as in providing valuable data to expand the yak genome information. 展开更多
关键词 YAK OVARY TRANSCRIPTOME RNA-SEQ improvement of gene structure REPRODUCTION
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Pushover analysis of underground structures:Method and application 被引量:21
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作者 LIU JingBo WANG WenHui DASGUPTA Gautam 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第2期423-437,共15页
Pushover analysis is common because of its conceptual simplicity and computational attractiveness in computing seismic demand.Considering that traditional pushover analysis is restricted in underground structures due ... Pushover analysis is common because of its conceptual simplicity and computational attractiveness in computing seismic demand.Considering that traditional pushover analysis is restricted in underground structures due to the stark differences in the seismic response characteristics of surface structures,this paper proposes a pushover analysis method for underground structures and its application in seismic damage assessment.First,three types of force distribution are presented based on ground response analysis.Next,the target displacements and analysis models are established according to force-based and performance-based design.Then,the pushover analysis procedure for underground structures is described.Next,the applicability of pushover analysis to underground structures is verified by comparing the responses of a Chongwenmen subway station determined by the proposed procedure and by nonlinear response history analysis.In addition,two other points are made:that the inverted triangular distribution of effective earthquake acceleration is more practical than the other two distributions,and that performance-based design is more effective than force-based design.Finally,a cyclic reversal loading pattern based on one cycle of reversal loads as an earthquake event is presented and applied to the seismic damage assessment of underground structures.The results show that the proposed pushover analysis can be effectively applied to the seismic design and damage assessment of underground structures. 展开更多
关键词 underground structure pushover analysis seismic demand seismic damage assessment
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Graphene nanopores toward DNA sequencing: a review of experimental aspects 被引量:2
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作者 Wei Chen Guo-Chang Liu +3 位作者 Jun Ouyang Meng-Juan Gao Bo Liu Yuan-Di Zhao 《Science China Chemistry》 SCIE EI CAS CSCD 2017年第6期721-729,共9页
Nanopores for DNA sequencing have drawn much attention due to their potentials to achieve amplification-free, low-cost, and high-throughput analysis of nuclei acids. The material configuration and fabrication of the n... Nanopores for DNA sequencing have drawn much attention due to their potentials to achieve amplification-free, low-cost, and high-throughput analysis of nuclei acids. The material configuration and fabrication of the nanopore has become one important consideration in the nanopore based DNA sequencing research. Among various materials, the newly emerged graphene has brought more opportunities to the development of sequencing technology because of its unique structures and properties. This review mainly focuses on the experimental aspects of graphene nanopore research including the nanopore fabrication methods and processes. Meanwhile, the challenges in the present graphene nanopore research including hydrophobicity, translocation velocity and noise are also addressed and discussed. 展开更多
关键词 graphene nanopore DNA sequencing nanopore fabrication
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Finite element method for viscoelastic medium with damage and the application to structural analysis of solid rocket motor grain 被引量:2
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作者 DENG Bin SHEN ZhiBin +1 位作者 DUAN JingBo TANG GuoJin 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第5期908-915,共8页
This paper studies the damage-viscoelastic behavior of composite solid propellants of solid rocket motors(SRM).Based on viscoelastic theories and strain equivalent hypothesis in damage mechanics,a three-dimensional(3-... This paper studies the damage-viscoelastic behavior of composite solid propellants of solid rocket motors(SRM).Based on viscoelastic theories and strain equivalent hypothesis in damage mechanics,a three-dimensional(3-D)nonlinear viscoelastic constitutive model incorporating with damage is developed.The resulting viscoelastic constitutive equations are numerically discretized by integration algorithm,and a stress-updating method is presented by solving nonlinear equations according to the Newton-Raphson method.A material subroutine of stress-updating is made up and embedded into commercial code of Abaqus.The material subroutine is validated through typical examples.Our results indicate that the finite element results are in good agreement with the analytical ones and have high accuracy,and the suggested method and designed subroutine are efficient and can be further applied to damage-coupling structural analysis of practical SRM grain. 展开更多
关键词 composite solid propellant viscoelasticity with damage f'mite element method integration algorithm stress-updatingmethod
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