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A Few Integrable Dynamical Systems,Recurrence Operators,Expanding Integrable Models and Hamiltonian Structures by the r-Matrix Method 被引量:1
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作者 张玉峰 Iqbal Muhammad 岳超 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第10期463-470,共8页
We extend two known dynamical systems obtained by Blaszak, et al. via choosing Casimir functions and utilizing Novikov-Lax equation so that a series of novel dynamical systems including generalized Burgers dynamical s... We extend two known dynamical systems obtained by Blaszak, et al. via choosing Casimir functions and utilizing Novikov-Lax equation so that a series of novel dynamical systems including generalized Burgers dynamical system, heat equation, and so on, are followed to be generated. Then we expand some differential operators presented in the paper to deduce two types of expanding dynamical models. By taking the generalized Burgers dynamical system as an example, we deform its expanding model to get a half-expanding system, whose recurrence operator is derived from Lax representation, and its Hamiltonian structure is also obtained by adopting a new way. Finally, we expand the generalized Burgers dynamical system to the (29-1)-dimensional case whose Hamiltonian structure is derived by Poisson tensor and gradient of the Casimir function. Besides, a kind of (29-1)-dimensional expanding dynamical model of the (29-1)-dimensionaJ dynamical system is generated as well. 展开更多
关键词 r-matrix poisson tensor expanding dynamical system
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Electron impact excitation of Ni-like gold studied by Dirac R-matrix method
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作者 范全平 汪文慧 +4 位作者 胡峰 曹磊峰 张强强 刘钰薇 蒋刚 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期261-267,共7页
We calculate the electron impact excitation of Ni-like gold by using the Dirac R-matrix theory, and the cor- responding collision strengths and effective collision strengths are obtained. In the calculations of the le... We calculate the electron impact excitation of Ni-like gold by using the Dirac R-matrix theory, and the cor- responding collision strengths and effective collision strengths are obtained. In the calculations of the level energy, (1sZ2sZ2p6)3sZ3p63d10, 3s23p63d94/, 3s23p53d104/, and 3s3p63d104/(l = 0, 1,2,3) configurations are included and 107 fine-structure levels are generated. In the calculations of the collision strengths, only the first 59 levels are included. Com- parisons are made with the distorted wave (DW) results of Zeng et al. for both collision strengths and effective collision strengths. For the collision strengths, the two sets of calculations are in excellent agreement for most of the transitions. However, because of the inclusion of the resonances, our effective collision strengths are generally several times larger than those of Zeng et al.. The accuracy of our calculations is assessed. 展开更多
关键词 electron impact excitation r-matrix method Ni-like gold
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Relativistic R-matrix calculations for L-shell photoionization cross sections of CⅡ
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作者 Lu-You Xie Qian-Qian Man +2 位作者 Jian-Guo Wang Yi-Zhi Qu Chen-Zhong Dong 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期212-218,共7页
The photoionization cross section of the ground state 2s22p 2Po1/2 and the first excited state 2s22p2po1/2 of C II ions are systematically calculated using the fully relativistic R-matrix code DARC. The detailed reson... The photoionization cross section of the ground state 2s22p 2Po1/2 and the first excited state 2s22p2po1/2 of C II ions are systematically calculated using the fully relativistic R-matrix code DARC. The detailed resonances are presented and identified for the photon energy ranging from threshold (24.38 eV) up to 41.5 eV where the L-shell (2p, 2s) photoionization process is dominant. In the calculations, the relativistic effect and electronic correlation effect are well considered. It is found that the relativistic effect is very important for the light atomic system CII, which accounts for experimentally observed fine structure resonance peaks. A careful comparison is made between the present results and the experimental values, and also other theoretical data available in the literature, showing that good agreement is obtained for the resonance peaks. 展开更多
关键词 photoionization cross section relativistic r-matrix method C II
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Quantum Yang-Baxter equation and constant R-matrix over Grassmann algebra
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作者 DUPLIJ Steven KOTULSKA Olga SADOVNIKOV Alexander 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第10期1065-1079,共15页
Constant solutions to Yang-Baxter equation are investigated over Grassmann algebra for the case of 6-vertex R-matrix. The general classification of all possible solutions over Grassmann algebra and particular cases wi... Constant solutions to Yang-Baxter equation are investigated over Grassmann algebra for the case of 6-vertex R-matrix. The general classification of all possible solutions over Grassmann algebra and particular cases with 2,3,4 generators are studied. As distinct from the standard case, when R-matrix over number field can have a maximum 5 nonvanishing elements, we obtain over Grassmann algebra a set of new full 6-vertex solutions. The solutions leading to regular R-matrices which appear in weak Hopf algebras are considered. 展开更多
关键词 Constant solution Grassmann algebra REGULARITY r-matrix
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r-Matrix Structure for a Restricted Flow with Bargmann Constraint
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作者 CHEN Jin-Bing GENG Xian-Guo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3X期393-395,共3页
This paper deals with the integrability of a finite-dimensional Hamiltonian system linked with the generalized coupled KdV hierarchy. For this purpose the associated Lax representation is presented after an elementary... This paper deals with the integrability of a finite-dimensional Hamiltonian system linked with the generalized coupled KdV hierarchy. For this purpose the associated Lax representation is presented after an elementary calculation. It is shown that the Lax representation enjoys a dynamical r-matrix formula instead of a classical one in the Poisson bracket on R2N. Consequently the resulting system is proved to be completely integrable in view of its r-matrix structure. 展开更多
关键词 Poisson bracket Lax representation r-matrix Liouville integrability
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Relativistic RRR-matrix studies of photoionization processes of Ar^(5+)
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作者 李传莹 韩小英 +1 位作者 王建国 屈一至 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期216-220,共5页
The 3s–np photoionization processes of the ground state 2P1/2 and the metastable state 2P3/2 of Ar5+ are investigated using our recently developed relativistic R-matrix code, where the interactions between the bound... The 3s–np photoionization processes of the ground state 2P1/2 and the metastable state 2P3/2 of Ar5+ are investigated using our recently developed relativistic R-matrix code, where the interactions between the bound states and the continuum states are included. Both resonance positions and the oscillator strengths are in much better agreement with the absolute experimental measurements by Wang et al.[Wang J C, Lu M, Esteves D, Habibi M, Alna’washi G and Phaneuf R A 2007 Phys. Rev. A 75 062712] with a resolution of 80 meV than their theoretical results. The contributions of the two experimental unresolved transitions are distinguished in our calculations, which show that the transitions from the ground state also make significant contributions to some resonances. Our theoretical results are also in good agreement with the measurements for the first resonance with a higher resolution of 20 meV. 展开更多
关键词 photoionization r-matrix method Ar5+
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Error propagation with R-matrix model fitting 被引量:1
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作者 陈振鹏 张瑞 +1 位作者 孙业英 刘挺进 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2003年第3期225-234,共10页
The error propagation features with R-matrix model fitting 7Li, 11B and 17O systems have been researched systematically. Some laws of error propagation have been revealed, an experience formula for describing standard... The error propagation features with R-matrix model fitting 7Li, 11B and 17O systems have been researched systematically. Some laws of error propagation have been revealed, an experience formula for describing standard error propagation has been established, and the most possible error range for evaluated standard cross section of 6Li (n, α), 10B (n, α) and 10B (n, α1) has been determined. 展开更多
关键词 r-matrix model ERROR propagation covariance NUCLEAR standard CROSS section.
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R-matrix for the 8-Dimensional Spin Representation of Uq(so7) 被引量:1
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作者 Hong Mei HU Nai Hong HU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第2期485-497,共13页
The purpose of the paper is to describe the solution to the quantum Yang-Baxter equation associated with the 8-dimensional spin representation Tsp of Uq(so7).The self-duality of Tsp and the symmetry of the correspondi... The purpose of the paper is to describe the solution to the quantum Yang-Baxter equation associated with the 8-dimensional spin representation Tsp of Uq(so7).The self-duality of Tsp and the symmetry of the corresponding braiding matrix are proved.Also,the minimal polynomial of the braiding R-matrix of Tsp is presented explicitly in an ingenious method by taking advantage of nice features of the spin representation Tsp. 展开更多
关键词 Braiding r-matrix spin module minimal polynomial
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r-matrix and algebraic-geometric symplectic map
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作者 QIAO ZhijunInstitute of Mathematics and School of Mathematical Sciences, Peking University, Beijing 100871, China 《Chinese Science Bulletin》 SCIE EI CAS 1999年第2期114-118,共5页
A new Lax matrix is introduced for the integrable symplectic map (ISM), and the non-dynamical(i. e. constant) r-matrix of ISM is obtained. Moreover, an effective approach is systematically presented to construct the e... A new Lax matrix is introduced for the integrable symplectic map (ISM), and the non-dynamical(i. e. constant) r-matrix of ISM is obtained. Moreover, an effective approach is systematically presented to construct the explicit solution(here, the explicit solution means algebraic-geometric solution expressed by the Riemann-Theta function) of a soliton system or nonlinear evolution equation from Lax matrix, r-matrix, and the theory of nonlinearization through taking the Toda lattice as an example. The given algebraic-geometric solution of the Toda lattice is almost-periodic and includes the periodic and finite-band solution. 展开更多
关键词 SYMPLECTIC MAP r-matrix algebraic-geometric solution.
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The r-matrix for constrained flows
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作者 曾云波 《Chinese Science Bulletin》 SCIE EI CAS 1996年第9期705-708,共4页
The classical r-matrix and Poisson structure play an important role in our studying ofintegrable systems, since they contain underlying property of the system. Recently, inter-est has developed in the study of dynamic... The classical r-matrix and Poisson structure play an important role in our studying ofintegrable systems, since they contain underlying property of the system. Recently, inter-est has developed in the study of dynamical r-matrix structure, which depends also on thedynamical variables, and associated generalized Yang-Baxter equations. However, 展开更多
关键词 r-matrix POISSON STRUCTURE CONSTRAINED flow.
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CLASSICAL R-MATRIX APPROACH TO THE SYSTEM ASSOCIATED WITH THE THREE-WAVE INTERACTION EQUATIONS
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作者 张磊 朱思铭 《Annals of Differential Equations》 2000年第4期401-406,共6页
The r-matrix is established for the system associated with the three-wave Interaction equations. Via the r-matrix, 3N functionally independent and involutive integrals of motion are obtained, which shows that the sys... The r-matrix is established for the system associated with the three-wave Interaction equations. Via the r-matrix, 3N functionally independent and involutive integrals of motion are obtained, which shows that the system is completely integrable in the Liouville sense. 展开更多
关键词 r-matrix Liouville integrabilit4
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DB^(R)_(π)矩阵的线性互补问题的误差界
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作者 李艳艳 《鞍山师范学院学报》 2025年第4期1-7,共7页
为了研究DB^(R)_(π)矩阵H的线性互补问题的误差界,首先基于DB^(R)_(π)矩阵的结构特性,将其分解为两个矩阵之和B^(+)+C,其中B+是主对角元素为正的双严格对角占优矩阵,再结合矩阵H的[H^(-1)]∽和两个特殊不等式,得到max_(d∈[0,1]^(n))[... 为了研究DB^(R)_(π)矩阵H的线性互补问题的误差界,首先基于DB^(R)_(π)矩阵的结构特性,将其分解为两个矩阵之和B^(+)+C,其中B+是主对角元素为正的双严格对角占优矩阵,再结合矩阵H的[H^(-1)]∽和两个特殊不等式,得到max_(d∈[0,1]^(n))[(I-D+DH)^(-1)]∽的误差界. 展开更多
关键词 DB^(R)_(π)矩阵 线性互补 误差界
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反应堆用核截面处理程序RXSP的研发与验证 被引量:10
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作者 余健开 李松阳 +2 位作者 王侃 王冠博 余纲林 《核动力工程》 EI CAS CSCD 北大核心 2013年第S1期10-13,共4页
反应堆用核截面处理系统(RXSP)除了具有共振重造、线性化以及能量/角度分布处理等功能外,还实现了快速多普勒展宽、热化库插值、OpenMP并行加速等关键方法和算法。程序验证表明,RXSP能够准确、高效地将ENDF/B库的中子评价核数据制作成... 反应堆用核截面处理系统(RXSP)除了具有共振重造、线性化以及能量/角度分布处理等功能外,还实现了快速多普勒展宽、热化库插值、OpenMP并行加速等关键方法和算法。程序验证表明,RXSP能够准确、高效地将ENDF/B库的中子评价核数据制作成堆用蒙特卡罗程序(RMC)计算所需的连续能量点截面库。与评价核数据库的数据处理系统(NJOY)处理生成截面库的微观比较和基准题的宏观验证表明,RXSP与NJOY具有相同的计算精度,而RXSP的处理时间则大大缩短,满足了反应堆物理-热工水力耦合计算中所需的多次大量材料的温度相关截面库更新的要求。此外,RXSP还能处理ENDF/B-Ⅶ.1中子截面库中R-matrixLimited格式的共振参数。 展开更多
关键词 RXSP 快速多普勒展宽 r-matrix LIMITED
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非参数CD-CAT选题策略DWIR的拓展及其优化
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作者 李俊杰 郑慧婧 +1 位作者 周昱希 曾平飞 《江西师范大学学报(自然科学版)》 北大核心 2025年第2期111-119,共9页
该文将DWIR选题策略拓展出更加一般化的GDWIR方法,使得GDWIR方法的适用范围更广,同时采用Q-最优准则或可达矩阵R对GDWIR方法的初始选题进行进一步优化,提出了Q_GDWIR和R_GDWIR方法.研究发现:1)GDWIR方法的适用范围更广,且比DWIR选题策... 该文将DWIR选题策略拓展出更加一般化的GDWIR方法,使得GDWIR方法的适用范围更广,同时采用Q-最优准则或可达矩阵R对GDWIR方法的初始选题进行进一步优化,提出了Q_GDWIR和R_GDWIR方法.研究发现:1)GDWIR方法的适用范围更广,且比DWIR选题策略具有更好的性能;2)在属性个数较少的情况下,Q_DWIR和R_DWIR同样具有较高的属性掌握模式判准率,在认知诊断计算机化自适应性测试(CD-CAT)中可以采用实施条件更加简单易行Q_DWIR或R_DWIR方法作为选题策略;3)如果测量的属性个数超过5,那么Q_GDWIR和R_GDWIR方法比Q_DWIR和R_DWIR方法的优势更加明显,当数据量达到150时,CD-CAT应采用Q_GDWIR和R_GDWIR方法进行选题施测以提高CD-CAT的测试效率. 展开更多
关键词 认知诊断计算机化自适应性测试 非参数选题策略DWIR 可达矩R Q最优准则
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一类时标可积耦合系统及其双哈密顿结构
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作者 程如梦 董焕河 《曲阜师范大学学报(自然科学版)》 2025年第3期52-58,共7页
通过构造Lax算子,利用时标上的R-矩阵,建立基于时标的AKNS可积耦合系统,并利用递推算子构造Poisson张量,成功得到了其双哈密顿结构.选取特殊时标得到经典的AKNS可积耦合系统及其哈密顿结构.
关键词 R-矩阵 AKNS方程 时标 双哈密顿结构
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应用于AC/AC变换的M3C系统控制策略 被引量:1
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作者 李佳宇 韩源 +1 位作者 王建军 潘玥 《电气传动》 2025年第5期13-19,共7页
模块化多电平矩阵变换器(M3C)是一种可以直接实现AC-AC变换的多电平拓扑结构,在高压输电系统及直流配电系统中有良好的应用前景,但M3C内部存在的桥臂环流通道导致其控制结构十分复杂。为此,提出一种分层式系统控制策略。首先,基于常规... 模块化多电平矩阵变换器(M3C)是一种可以直接实现AC-AC变换的多电平拓扑结构,在高压输电系统及直流配电系统中有良好的应用前景,但M3C内部存在的桥臂环流通道导致其控制结构十分复杂。为此,提出一种分层式系统控制策略。首先,基于常规的双αβ0坐标变换,推导出M3C的数学模型。然后,将电压源变换器中常用的外环和内环控制器的双环控制结构应用到M3C中。此外,为了抑制系统内部的环流分量,提出了一种基于双αβ0变换解耦的桥臂能量均衡控制策略,通过该控制和载波移相调制实现桥臂和桥臂间的电容电压控制。最后,搭建仿真模型和实验样机,仿真及实验结果验证了所提M3C系统控制策略的可行性。 展开更多
关键词 模块化多电平矩阵变换器 双αβ0坐标变换 双闭环矢量控制 桥臂能量均衡
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基于无人机云台角度自适应调整的无感智能督查技术
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作者 黄锐鸿 黄烁 +2 位作者 黄毓琦 林宇生 林晓鹏 《西安工程大学学报》 2025年第6期112-119,共8页
传统电网督查手段准确度不高,容易漏检,为提高电网安全无感智能督查性能,给出一种新的督查技术。首先,对无人机无感智能督查技术问题进行分析,提出无人机云台角度自适应调整策略,通过无人机设备获得巡检图像信息,并展开预处理,提高图像... 传统电网督查手段准确度不高,容易漏检,为提高电网安全无感智能督查性能,给出一种新的督查技术。首先,对无人机无感智能督查技术问题进行分析,提出无人机云台角度自适应调整策略,通过无人机设备获得巡检图像信息,并展开预处理,提高图像质量;其次,利用Faster R-CNN算法获取遮挡目标位置信息,构建云台框架数学模型获得变换矩阵,以准确地将不同坐标系下的坐标进行转换;再次,将无人机载体坐标系变换到地理坐标系,并根据获得的遮挡目标位置和无人机当前的姿态变换信息、云台变换矩阵,得到无人机云台角度自适应调整角度;最后,云台主控控制无人机姿态,来进行定期巡查获得高清图像和视频数据,传输回监控中心后由运维人员完成督查。实验结果表明:该方法可精准实现对无人机云台角度的调整,督查准确率最高可达到98%,为电网的无感督查提供了借鉴。 展开更多
关键词 无感智能督查 无人机云台 变换矩阵 自适应调整 Faster R-CNN算法
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基于光谱重建技术的壁画颜色复原与评价 被引量:11
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作者 王可 王慧琴 +2 位作者 殷颖 毛力 张毅 《激光技术》 CAS CSCD 北大核心 2019年第2期280-285,共6页
为了在给定的照明和观察条件下,用相机响应信号重建物体表面光谱反射率,实现颜色的高精度复原,采用了多光谱成像技术采集物体表面的多光谱图像,使用主成分分析、R矩阵和正则化R矩阵方法进行了光谱反射率重建的理论研究,并对壁画色块颜... 为了在给定的照明和观察条件下,用相机响应信号重建物体表面光谱反射率,实现颜色的高精度复原,采用了多光谱成像技术采集物体表面的多光谱图像,使用主成分分析、R矩阵和正则化R矩阵方法进行了光谱反射率重建的理论研究,并对壁画色块颜色复原进行了实验验证,取得了壁画色块的重建光谱和颜色复原数据,同时对基于正则化R矩阵方法的壁画色块颜色复原结果进行了评价。结果表明,正则化R矩阵方法进行光谱重建的光谱精度和色度精度更高,与主成分分析和R矩阵方法相比,色差降低了0.0732,适应度系数提高了1.10%,均方根误差降低了0.0035,光谱匹配偏指数降低了0.0225。该方法能够满足高精度颜色再现的需要,适用于文物艺术品数字化存档、文物艺术品修复等领域。 展开更多
关键词 光谱学 颜色复原 R矩阵 正则化
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关于第二类r-循环矩阵的几个性质 被引量:7
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作者 赵立宽 李振 孟令霞 《曲阜师范大学学报(自然科学版)》 CAS 2009年第4期34-36,共3页
提出了第二类r-循环矩阵的概念,并给出了这类r-循环矩阵的几个性质.
关键词 循环矩阵 R-循环矩阵 第二类r-循环矩阵
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群体遗传学研究中STR数据的统计方法应用 被引量:4
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作者 桂宏胜 杨丽 李生斌 《遗传》 CAS CSCD 北大核心 2007年第12期1443-1448,共6页
STR作为遗传多态性较高的标记,被广泛地运用于群体遗传学的研究。对于STR分型产生的基因型频率及等位基因频率数据,文章总结了各种参数指标的计算及分析方法。其中参数指标包括杂合度、多态信息量、连锁不平衡系数、近交系数、遗传距离... STR作为遗传多态性较高的标记,被广泛地运用于群体遗传学的研究。对于STR分型产生的基因型频率及等位基因频率数据,文章总结了各种参数指标的计算及分析方法。其中参数指标包括杂合度、多态信息量、连锁不平衡系数、近交系数、遗传距离以及固定指数等;分析方法包括主成分分析、系统发生树、分子方差分析、R矩阵、地理信息系统以及空间自相关分析。通过这些参数指标及分析方法的使用,可以既直观又科学地揭示群体遗传结构、群体间遗传分化以及人类起源与进化等群体遗传学中研究的关键问题。 展开更多
关键词 STR 群体遗传学 主成分分析 系统发生树 AMOVA R矩阵 GIS 空间自相关
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