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Competing Patterns in Bernoulli Sequence of Trials
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作者 Paul Vrbik Jan Vrbik 《Applied Mathematics》 2023年第5期314-323,共10页
Consider performing a sequence of Bernoulli trials (each resulting in either a success, denoted S, or a failure F, with a probability of p and q := 1 - p respectively) until one of m specific strings (or patterns) of ... Consider performing a sequence of Bernoulli trials (each resulting in either a success, denoted S, or a failure F, with a probability of p and q := 1 - p respectively) until one of m specific strings (or patterns) of consecutive outcomes is generated. This can be seen as a game where m players select one such pattern each and the one whose pattern occurs first wins. We present symbolic formulas for the m probabilities of winning, and for the mean number of trials and the corresponding standard deviation to complete this game. Several numerical examples are presented, including a search for optimal strategy. 展开更多
关键词 Competing patterns Bernoulli sequence of Trials Game Theory
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Key technology of mine underground mobile positioning based on LiDAR and coded sequence pattern 被引量:4
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作者 WANG Zhi1, 2, WU Li-xin1, 2, LI Hui-ying3 1. College of Resources and Civil Engineering, Northeastern University, Shenyang 110004, China 2. Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs and Ministry of Education, Beijing Normal University, Beijing 100875, China 3. College of Computer Science and Technology, Jilin University, Changchun 130012, China 《中国有色金属学会会刊:英文版》 CSCD 2011年第S3期570-576,共7页
Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navi... Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3D scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3D mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom. 展开更多
关键词 LIDAR CODED sequence pattern mobile POSITIONING SLAM ALGORITHM POSIT ALGORITHM
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Sequence Patterns of Identity Authentication Protocols 被引量:2
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作者 陶宏才 何大可 《Journal of Southwest Jiaotong University(English Edition)》 2006年第3期205-211,共7页
From the viewpoint of protocol sequence, analyses are made of the sequence patterns of possible identity authentication protocol under two cases: with or without the trusted third party (TFP). Ten feasible sequence... From the viewpoint of protocol sequence, analyses are made of the sequence patterns of possible identity authentication protocol under two cases: with or without the trusted third party (TFP). Ten feasible sequence patterns of authentication protocol with TIP and 5 sequence patterns without TFP are gained. These gained sequence patterns meet the requirements for identity authentication, and basically cover almost all the authentication protocols with TFP and without TFP at present. All of the sequence patterns gained are classified into unilateral or bilateral authentication. Then, according to the sequence symmetry, several good sequence patterns with TFP are evaluated. The accompolished results can provide a reference to design of new identity authentication protocols. 展开更多
关键词 Authentication protocol Identity authentication sequence pattern TTP
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Inference of Global HIV-1 Sequence Patterns and Preliminary FeatureAnalysis 被引量:1
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作者 Yan Wang Reda Rawi +2 位作者 Daniel Hoffmann Binlian Sun Rongge Yang 《Virologica Sinica》 SCIE CAS CSCD 2013年第4期228-238,共11页
The epidemiology of HIV-1 varies in different areas of the world, and it is possible that this complexity may leave unique footprints in the viral genome. Thus, we attempted to find significant patterns in global HIV-... The epidemiology of HIV-1 varies in different areas of the world, and it is possible that this complexity may leave unique footprints in the viral genome. Thus, we attempted to find significant patterns in global HIV-1 genome sequences. By applying the rule inference algorithm RIPPER (Repeated Incremental Pruning to Produce Error Reduction) to multiple sequence alignments of Env sequences from four classes of compiled datasets, we generated four sets of signature patterns. We found that these patterns were able to distinguish southeastern Asian from non- southeastern Asian sequences with 97.5% accuracy, Chinese from non-Chinese sequences with 98.3% accuracy, African from non-African sequences with 88.4% accuracy, and southern African from non-southern African sequences with 91.2% accuracy. These patterns showed different associations with subtypes and with amino acid positions. In addition, some signature patterns were characteristic of the geographic area from which the sample was taken. Amino acid features corresponding to the phylogenetic clustering of HIV-1 sequences were consistent with some of the deduced patterns. Using a combination of patterns inferred from subtypes B, C, and all subtypes chimeric with CRF01_AE worldwide, we found that signature patterns of subtype C were extremely common in some sampled countries (for example, Zambia in southern Africa), which may hint at the origin of this HIV-1 subtype and the need to pay special attention to this area of Africa. Signature patterns of subtype B sequences were associated with different countries. Even more, there are distinct patterns at single position 21 with glycine, leucine and isoleucine corresponding to subtype C, B and all possible recombination forms chimeric with CRF01_AE, which also indicate distinct geographic features. Our method widens the scope of inference of signature from geographic, genetic, and genomic viewpoints. These findings may provide a valuable reference for epidemiological research or vaccine design. 展开更多
关键词 pattern inference global HIV- 1 sequence Repeated Incremental Pruning to Produce Error Reduction (RIPPER)
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Seismic Sequence Structure and Earthquakes Triggering Patterns 被引量:2
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作者 Giulio Riga Paolo Balocchi 《Open Journal of Earthquake Research》 2016年第1期20-34,共15页
Within a time distribution of magnitude values, before any mainshock some earthquake triggering patterns with several features develop, under tectonic processes’ influence, through which it is possible to early ident... Within a time distribution of magnitude values, before any mainshock some earthquake triggering patterns with several features develop, under tectonic processes’ influence, through which it is possible to early identify the preparation phase of big earthquakes. The purpose of this article was to identify and classify the warning patterns that develop before a big earthquake by considering space-time seismicity variations. The methodological approach adopted was of graphical type, based on procedures of technical analysis currently used to estimate the financial markets. In the initial phase of the study we have analyzed the seismic sequences types described in the bibliography (type 1: foreshocks-mainshock-aftershocks, type 2: mainshock-aftershock;type 3: swarm) and the main structure of the seismic cycle, within which maximum and minimum magnitude values characterize the pattern that it develops until the main event changes. Then, we assessed the position of foreshocks, mainshock and aftershocks within the seismic cycle in order to identify the warning pattern that characterized the exact time when the energy emission occurs. As to the evolution normally shown over time, we have grouped the warning patterns in 2 categories: 1) progressive earthquake pattern;2) flash earthquake pattern. Finally, we have made a classification of the warning pattern related to the fluctuations of maximum and minimum magnitude values, compared its form with the mainshock’s focal mechanism and suggested some graphic procedures in order to estimate the mainshock magnitude value associated with each warning pattern. The results we obtained unquestionably allow a better comprehension of preparation process of a large earthquake, improving the earthquakes forecasting probability in the next future. 展开更多
关键词 FORESHOCK Classification sequence Cycle pattern TRIGGER EARTHQUAKE
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Positional Information Storage in Sequence Patterns
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作者 Alexey A. Shadrin Andrei Grigoriev Dmitri V. Parkhomchuk 《Computational Molecular Bioscience》 2013年第2期18-26,共9页
We build a model of storage of well-defined positional information in probabilistic sequence patterns. Once a pattern is defined, it is possible to judge the effect of any mutation in it. We show that the frequency of... We build a model of storage of well-defined positional information in probabilistic sequence patterns. Once a pattern is defined, it is possible to judge the effect of any mutation in it. We show that the frequency of beneficial mutations can be high in general and the same mutation can be either advantageous or deleterious depending on the pattern’s context. The model allows to treat positional information as a physical quantity, formulate its conservation law and to model its continuous evolution in a whole genome, with meaningful applications of basic physical principles such as optimal efficiency and channel capacity. A plausible example of optimal solution analytically describes phase transitions-like behavior. The model shows that, in principle, it is possible to store error-free information on sequences with arbitrary low conservation. The described theoretical framework allows one to approach from novel general perspectives such long-standing paradoxes as excessive junk DNA in large genomes or the corresponding G- and C-values paradoxes. We also expect it to have an effect on a number of fundamental concepts in population genetics including the neutral theory, cost-of-selection dilemma, error catastrophe and others. 展开更多
关键词 INFORMATION Theory sequence pattern GENETIC INFORMATION CONSERVATION TYPICAL SET
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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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The Sequence Architecture of Volcanic Basin Fillings-An Example From Xujiaweizi Faulted Depression In Songliao Basin 被引量:3
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作者 CHENG Rihui, LIU Wanzhu, SHAN Xuanlong, WANG Pujun (Faculty of Earth Sciences at Jilin University, Changchun, 130061, P.R.China) CHEN Shumin and QU Yongbao (Daqing Petroleum Bureau Prospecting and Exploration Institute, Daqing, 163712, P.R.China) 《Global Geology》 2001年第2期116-119,128,共5页
The basin filling geometric pattern of volcanic eruptive rocks depends on both of the eruptive locations in a basin and structural styles of fault terraces. It is divided into three types by eruptive locations and occ... The basin filling geometric pattern of volcanic eruptive rocks depends on both of the eruptive locations in a basin and structural styles of fault terraces. It is divided into three types by eruptive locations and occurrences of eruptive rocks, including the pattern of eruption along fault and occurrence (PEAFO), the pattern of eruption on footwall of a fault and occurrence (PEOFO) and the pattern of eruption on hangingwall of fault and occurrence (PEOHO) in Xujiaweizi fault depression of Songliao basin, Northeast of China. Those basin filling patterns of volcanic eruptive rocks are of specific geometric characteristics controlling or affecting sedimentation, geometry of sedimentary body and sequence architecture during a sequence evolution. The study shows that the volcanic rocks developed at different stages of lowstand, transgressive and highstand can give different controls or affects on the sequence architecture. 展开更多
关键词 ERUPTIVE Rock Basin FILLING pattern and sequence ARCHITECTURE
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Rice bicoid-related cDNA sequence and its expression during early embryogenesis 被引量:3
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作者 YangZX AnGY 《Cell Research》 SCIE CAS CSCD 2001年第1期74-80,共7页
Bicoid is one of the important Drosophila maternal genes involved in the control of embryo polarity and larvae segmentation. To clone and characterize the rice bicoid-related genes, one cDNA clone, Rb24 (EMBL accessio... Bicoid is one of the important Drosophila maternal genes involved in the control of embryo polarity and larvae segmentation. To clone and characterize the rice bicoid-related genes, one cDNA clone, Rb24 (EMBL accession number: AJ2771380), was isolated by screening of rice unmature seed cDNA library. Sequence analysis indicates that Rb24 contains a putative amino acid sequence, which is homologous to unique 8 amino acids sequence within Drosophila bicoid homeodomain (50% identity, 75% similarity) and involves a lys-9 in putative helix 3. Northern blot analysis of rice RNA has shown that this sequence is expressed in a tissue-specific manner. The transcript was detected strongly in young panicles, but less in young leaves and roots. This results are further confirmed with paraffin section in situ hybridization. The signal is intensive in rice globular embryo and located at the apical tip of the embryo, then, along with the development of embryo, the signal is getting reduced and transfers into both sides of embryo. The existence of bicoid-related sequence in rice embryo and the similarity of polar distribution of bicoid and Rb24 mRNA in early embryo development may implicates a conserved maternal regulation mechanism of body axis presents in Drosophila and in rice. 展开更多
关键词 Base sequence Body patterning Cloning Molecular DNA Complementary Gene Expression Regulation Plant Genes Plant Homeodomain Proteins Molecular sequence Data Oryza sativa Protein Structure Tertiary Research Support Non-U.S. Gov't Seeds sequence Homology Nucleic Acid TRANS-ACTIVATORS
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Active motif finder-a bio-tool based on mutational structures in DNA sequences
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作者 Mani Udayakumar Palaniyandi Shanmuga-priya +1 位作者 Kamalakannan Hemavathi Rengasamy Seenivasagam 《The Journal of Biomedical Research》 CAS 2011年第6期444-448,共5页
Active Motif Finder (AMF) is a novel algorithmic tool, designed based on mutations in DNA sequences. Tools available at present for finding motifs are based on matching a given motif in the query sequence. AMF descr... Active Motif Finder (AMF) is a novel algorithmic tool, designed based on mutations in DNA sequences. Tools available at present for finding motifs are based on matching a given motif in the query sequence. AMF describes a new algorithm that identifies the occurrences of patterns which possess all kinds of mutations like insertion, deletion and mismatch. The algorithm is mainly based on the Alignment Score Matrix (ASM) computation by com paring input motif with full length sequence. Much of the effort in bioinformatics is directed to identify these motifs in the sequences of newly discovered genes. The proposed bio-tool serves as an open resource for analysis and useful for studying polymorphisms in DNA sequences. AMF can be searched via a user-friendly interface. This tool is intended to serve the scientific community working in the areas of chemical and structural biology, and is freely available to all users, at http://www.sastra.edu/scbt/amf/. 展开更多
关键词 MUTATIONS alignment score matrix back track INDELS pattern occurrence DNA sequences.
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The fracture characteristic of the 1989 Datong-Yanggao earthquake sequence
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作者 张四昌 刁桂苓 于利民 《Earthquake Science》 CSCD 1994年第S1期13-21,共9页
This paper, first, analyzed the seismic activity patterns of the Datong-Yanggao earthquake sequence by 4 stages,finding that three times earthquakes of Mis were located in a same NNE seismically active zone and two ti... This paper, first, analyzed the seismic activity patterns of the Datong-Yanggao earthquake sequence by 4 stages,finding that three times earthquakes of Mis were located in a same NNE seismically active zone and two times located in 2 NWW seismically active zones. Then the focal-mechanism solutions of 12 earthquakes of M≥4 and 114 earthquakes of M≥1. 0 in various zones were obtained, a tectonic analysis was made for these data, the obtained fracture characteristic of this sequence is: the conjugate fracture combination with the NNE right lateral faults as its trunk and the two NWW left lateral faults as its branches. Finally, it is pointed out that there is an obvious difference between the seismic fracture and the tensile dip-slip tectonic activity of the main body of the seismic region. 展开更多
关键词 Datong-Yanggao earthquake sequence seismic activity pattern focal mechanism conjugate seismic fracture
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Consequences of Non-Uniformity in the Stoichiometry of Component Fractions within One and Two Loops Models of α-Helical Peptides
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作者 Walter F. Schmidt Cathleen J. Hapeman +1 位作者 James Wachira Clayton G. Thomas 《Journal of Biophysical Chemistry》 2014年第4期125-133,共9页
A 3-D electrostatic density map generated using the Wavefront Topology System and Finite Element Method clearly demonstrates the non-uniformity and periodicity present in even a single loop of an α-helix. The four di... A 3-D electrostatic density map generated using the Wavefront Topology System and Finite Element Method clearly demonstrates the non-uniformity and periodicity present in even a single loop of an α-helix. The four dihedral angles (N-C*-C-N, C*-C-N-C*, and C-N-C*-C) fully define a helical shape independent of its length: the three dihedral angles, φ = -33.5°, ω = 177.3°, and Ψ = -69.4°, generate the precise (and identical) redundancy in a one loop (or longer) α-helical shape (pitch = 1.59 /residue;r = 2.25 ). Nevertheless the pattern of dihedral angles within an 11 and a 22-peptide backbone atom sequence cannot be distributed evenly because the stoichiometry in fraction of four atoms never divides evenly into 11 or 22 backbone atoms. Thus, three sequential sets of 11 backbone atoms in an α-helix will have a discretely different chemical formula and correspondingly different combinations of molecular forces depending upon the assigned starting atom in an 11-step sequence. We propose that the unit cell of one loop of an α-helix occurs in the peptide backbone sequence C-(N-C*-C)3-N which contains an odd number of C* plus even number of amide groups. A two-loop pattern (C*-C-N)7-C* contains an even number of C* atoms plus an odd number of amide groups. Dividing the two-loop pattern into two equal lengths, one fraction will have an extra half amide (N-H) and the other fraction will have an extra half amide C=O, i.e., the stoichiometry of each half will be different. Also, since the length of N-C*-C-N, C*-C-N-C*, and C-N-C*-C are unequal, the summation of the number of each in any fraction of n loops of an α-helix in sequence will always have unequal length, depending upon the starting atom (N, C*, or C). 展开更多
关键词 pattern Recognition Α-HELIX Dihedral Angle patterns Peptide BACKBONE sequence Molecular Orbital Theory Electrostatic Density Gradient Wavefront Topology System Finite Element Method
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Hidden Sequence Repeats: Additional Evidence for the Origin of TIM-Barrel Family
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作者 Xiaofeng Ji Yuan Zheng +1 位作者 Zhipeng Wang Jun Sheng 《Journal of Biomedical Science and Engineering》 2016年第6期307-314,共8页
Most proteins adopt an approximate structural symmetry. However, they have no symmetry detectable in their sequences and it is unclear for most of these proteins whether their structural symmetry originates from dupli... Most proteins adopt an approximate structural symmetry. However, they have no symmetry detectable in their sequences and it is unclear for most of these proteins whether their structural symmetry originates from duplication. As one of the six popular folds (super-folds) possessing an approximate structural symmetry, the triosephosphate isomerase barrel (TIM-barrel) domain has been widely studied. Using modified recurrent quantification analysis of primary sequences, we identified the same 2-, 3-, and 4-fold symmetry pattern as their tertiary structures. This result indicates that the symmetry in tertiary structure is coded by symmetry in the primary sequence and that the TIM-barrel adopts a 2-, 3-, or 4-fold repeat pattern during evolution. This discovery will be useful for understanding the evolutionary mechanisms of this protein family and the symmetry pattern that may be a clue into the ancient origin of duplication of half-barrels or the β a unit. 展开更多
关键词 TIM-Barrel Hidden Symmetry Primary sequences Repeat pattern Recurrence Quantification Analysis
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Multi-Value Sequence Generated over Sub Extension Field and Its Properties
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作者 Md. Arshad Ali Yuta Kodera +3 位作者 Takuya Kusaka Satoshi Uehara Yasuyuki Nogami Robert H. Morelos-Zaragoza 《Journal of Information Security》 2019年第3期130-154,共25页
Pseudo-random sequences with long period, low correlation, high linear complexity, and uniform distribution of bit patterns are widely used in the field of information security and cryptography. This paper proposes an... Pseudo-random sequences with long period, low correlation, high linear complexity, and uniform distribution of bit patterns are widely used in the field of information security and cryptography. This paper proposes an approach for generating a pseudo-random multi-value sequence (including a binary sequence) by utilizing a primitive polynomial, trace function, and k-th power residue symbol over the sub extension field. All our previous sequences are defined over the prime field, whereas, proposed sequence in this paper is defined over the sub extension field. Thus, it’s a new and innovative perception to consider the sub extension field during the sequence generation procedure. By considering the sub extension field, two notable outcomes are: proposed sequence holds higher linear complexity and more uniform distribution of bit patterns compared to our previous work which defined over the prime field. Additionally, other important properties of the proposed multi-value sequence such as period, autocorrelation, and cross-correlation are theoretically shown along with some experimental results. 展开更多
关键词 PSEUDO-RANDOM sequence Trace Function Power RESIDUE Symbol SUB Extension Field AUTOCORRELATION CROSS-CORRELATION Linear Complexity Distribution of Bit patterns
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Theoretical Bounds and Practical Constructions for Families of One-Coincidence Sequences in FHMA
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作者 MeiWenhua YangYixian 《通信学报》 EI CSCD 北大核心 1995年第4期74-78,共5页
TheoreticalBoundsandPracticalConstructionsforFamiliesofOne-CoincidenceSequencesinFHMAMeiWenhua;YangYixian(Be... TheoreticalBoundsandPracticalConstructionsforFamiliesofOne-CoincidenceSequencesinFHMAMeiWenhua;YangYixian(BeijingAeronautical... 展开更多
关键词 跳频通信 跳动模式 一致性 跳频多址
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花生COP1基因的克隆及表达特征分析
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作者 杨永庆 胡朋举 +1 位作者 李玉荣 王瑾 《中国油料作物学报》 CAS CSCD 北大核心 2024年第4期819-825,共7页
为了探究花生中COP1基因的序列及表达特征,本研究从花生中克隆获得2个COP1基因,分别命名为AhyCOP1a和AhyCOP1b,以此为基础进行了相关分析。结果显示,AhyCOP1a和AhyCOP1b分别长2103 bp和2049 bp,均含有13个外显子和12个内含子。聚类结果... 为了探究花生中COP1基因的序列及表达特征,本研究从花生中克隆获得2个COP1基因,分别命名为AhyCOP1a和AhyCOP1b,以此为基础进行了相关分析。结果显示,AhyCOP1a和AhyCOP1b分别长2103 bp和2049 bp,均含有13个外显子和12个内含子。聚类结果显示AhyCOP1a和AhyCOP1b与双子叶作物的COP1基因聚成一类,且分别与AduCOP1和AipCOP1亲缘关系最近,表明AhyCOP1a和AhyCOP1b的进化分别始于花生野生种Ar⁃achis duranensis和A.ipaensis。此外,AhyCOP1a和AhyCOP1b分别有6个和7个WD40重复基序。各类物种的COP1基因在N端相似度较低,在C端WD40结构域部分相似性较高,表明WD40结构域是COP1基因的主要核心功能区域。组织表达结果显示,AhyCOP1a和AhyCOP1b在地上部的表达显著高于地下部,花中最高,其次为叶和茎。但AhyCOP1a在地下组织的表达量在显著高于AhyCOP1b,暗示AhyCOP1a在地下组织发育过程中的作用更大。此外还发现光照可以促进花生COP1基因的表达,表明花生中COP1基因的表达受光照显著影响。总之,本研究结果初步明确了花生中COP1基因的序列及表达特征,为后续深入探究COP1基因的分子功能奠定了基础。 展开更多
关键词 花生 COP1 序列比对 表达特征
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“潜水”还是“学习”:在线协作学习中“在线倾听”行为再审视
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作者 王中国 彭文辉 +1 位作者 刘清堂 史玲玲 《电化教育研究》 CSSCI 北大核心 2024年第3期77-84,共8页
学习者“在线倾听”行为是一种复杂的社会化活动,是在线协作学习对话的前提和基础,但并未引起正视和积极理解。基于对话教学理论视角,研究采用滞后序列分析、内容分析、社会网络分析等研究方法,分析学习者“在线倾听”行为模式特征,及... 学习者“在线倾听”行为是一种复杂的社会化活动,是在线协作学习对话的前提和基础,但并未引起正视和积极理解。基于对话教学理论视角,研究采用滞后序列分析、内容分析、社会网络分析等研究方法,分析学习者“在线倾听”行为模式特征,及其对学习者认知过程、批判性思维和学习绩效的潜在影响。研究发现,学习者“在线倾听”行为是在线协作学习的常态行为,存在显著性差异,在时间结构上呈现周期性和阵发性;专注的“在线倾听”,高频次的回顾/反思倾听,有益于学习者高水平知识建构和批判性思维发展;高、低绩效学习者群体的“在线倾听”行为模式存在显著差异,高绩效组“在线倾听”行为更专注、行为路径更完整。这些发现为理解和解释数字教育场景下在线学习发生的内隐规律和内在机制提供理论支撑和实践参考。 展开更多
关键词 在线倾听 在线发言 在线协作学习 行为序列模式 内在机制
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基于需求模式自适应匹配的间歇性需求预测方法
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作者 范黎林 曹富康 +2 位作者 王琬婷 杨凯 宋钊瑜 《计算机应用》 CSCD 北大核心 2024年第9期2747-2755,共9页
大型制造企业售后配件的需求分布稀疏、波动性大,需求频率和需求数量不确定性较高,序列呈现出典型的间歇性特点。在实际运维中,配件需求在频率和数量方面存在较大波动,从而产生变化多样的需求模式,而现有间歇性需求预测主要采用单一或... 大型制造企业售后配件的需求分布稀疏、波动性大,需求频率和需求数量不确定性较高,序列呈现出典型的间歇性特点。在实际运维中,配件需求在频率和数量方面存在较大波动,从而产生变化多样的需求模式,而现有间歇性需求预测主要采用单一或静态组合的固定预测模型,难以充分挖掘不同需求模式下需求序列的演化规律,预测精度和稳定性均难以保证。为解决上述问题,提出一种基于需求模式自适应匹配的间歇性需求预测方法,通过动态识别和匹配需求模式提升间歇性序列预测效果。该方法包括两个阶段:在模型训练阶段,首先,根据配件历史需求数据的间歇性特征,将它划分为需求量序列和间隔量序列,并对两类序列分别进行聚类,以捕获每类序列对应的不同需求和间隔模式;其次,建立包含统计学分析模型、浅层机器学习模型及深度学习模型的预测模型库,测试各模型对每种需求模式的预测效果,识别并标记每类需求模式的最优预测模型。在预测阶段,将待预测序列划分为需求量序列和间隔量序列,确定需求模式并匹配最佳预测模型,进而将需求量和间隔量的预测值合并,形成最终预测结果。在美国汽车公司和英国空军的间歇性配件需求数据集上的实验结果表明,所提方法可适用于不同需求模式的配件历史数据,通过自适应匹配需求模式和最优预测模型,有效提升了预测精度。 展开更多
关键词 间歇性序列 需求预测 时间序列预测 需求模式识别 配件管理
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儿童首发精神分裂症患者和健康儿童听觉感觉门控P50的对照研究
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作者 张郦 刘占文 +4 位作者 谢志兵 李婷 季海峰 张静洁 陈思路 《临床精神医学杂志》 CAS 2024年第5期382-385,共4页
目的:探讨感觉门控(sensory gating,SG)P50新技术对儿童首发精神分裂症(children onset schizophrenia,COS)患者SG抑制的特点。方法:应用德国脑电生理仪,P50刺激序列采用S1和S2范式,对56例COS患者和38名健康儿童(healthy children,HC)作... 目的:探讨感觉门控(sensory gating,SG)P50新技术对儿童首发精神分裂症(children onset schizophrenia,COS)患者SG抑制的特点。方法:应用德国脑电生理仪,P50刺激序列采用S1和S2范式,对56例COS患者和38名健康儿童(healthy children,HC)作了P50检测。并用阳性和阴性症状量表(positive and negative syndrome scale,PANSS)、社会功能缺陷量表(social disability screening schedule,SDSS)、家庭负担会谈量表(family interview schedule,FIS)和自制力与治疗态度问卷量表(insight and therapeutic attitude questionaire,ITAQ)对COS患者进行综合评估。结果:COS组未发现P50与PANSS量表总分、各因子分的相关性(P>0.05)。与HC相比,COS组P50中的Fz区S2波幅增高,与Cz区和Pz区S2波幅同一趋势(P<0.05或P<0.01)。结论:COS患者同成人精神分裂症一样存在P50异常。P50抑制变化可能是反映患者激越情绪变化的脑电生理指标。此初步结果有待于临床随访中及转化中进一步证实。 展开更多
关键词 精神分裂症 儿童 感觉门控 P50 刺激序列模式 生物学标记
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差序格局下高职中外合作办学高质量发展路径研究
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作者 夏雪 《教育教学论坛》 2024年第18期53-56,共4页
在“十四五”时期教育对外开放的背景下,封闭的高等教育系统已被打破,我国职业院校与国际主体间交流日益紧密,高质量发展成为新时代对高职院校中外合作办学的核心要求。当前教育对外开放政策、职业教育发展规划、社会需求、资源分配等... 在“十四五”时期教育对外开放的背景下,封闭的高等教育系统已被打破,我国职业院校与国际主体间交流日益紧密,高质量发展成为新时代对高职院校中外合作办学的核心要求。当前教育对外开放政策、职业教育发展规划、社会需求、资源分配等多方面的因素共同形成了高职中外合作办学差序格局。通过不同的半径对高职中外合作办学差序格局进行观察与分析,探究高职中外合作办学差序格局形成的动力机制,分析当前存在的问题,探索新时代高职中外合作办学质量提升的对策。 展开更多
关键词 高职中外合作办学 差序格局 高质量发展路径
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