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Controlling Chaos in Hénon Map by the Constant Feedback Method 被引量:1
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作者 HAO Jian-Hong XU Hai-Bo YU Jin-Jiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2X期279-287,共9页
We demonstrate the constant feedback and the modified constant feedback method to the Hénon map. Using the convergence of the chaotic orbit in finite time, we can control the system from chaos to the stable fixed... We demonstrate the constant feedback and the modified constant feedback method to the Hénon map. Using the convergence of the chaotic orbit in finite time, we can control the system from chaos to the stable fixed point, and even to the stable period-2 orbit or higher periodic orbit by the action of a proper feedback strength and pulse interval. We also find that the multi-steady solutions appear with the same control strength and different initial conditions. The aim of this control method is explicit and the feedback strength is easy to determine. The method is robust under the presence of weak external noise. 展开更多
关键词 constant feedback modified constant feedback finite time convergence zone non map multisteady solutions
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Regime Map of Dry Neutralization Agglomeration Process Containing Non-Reactive Ingredient on a Laboratory Scale 被引量:1
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作者 Leping Dang Xu Li +2 位作者 Jinsheng Fu Xiaojun Lang Hongyuan Wei 《Transactions of Tianjin University》 EI CAS 2019年第1期66-73,共8页
This study described a regime map for dry neutralization agglomeration. Based on the map, the effects of selected key parameters, such as ingredient composition, operation temperature, agitation speed, and size of Na_... This study described a regime map for dry neutralization agglomeration. Based on the map, the effects of selected key parameters, such as ingredient composition, operation temperature, agitation speed, and size of Na_2CO_3 particles, were investigated using a laboratory-scale mixer, and properties of the agglomeration product were analyzed, including particle size distribution, Hunter color, and flowability. Torque curves evolving during the process were correlated with the system flowability. Three distinguishable regimes were indicated, dry, wet, and transitional, and the agitation speed was found to have a different influence on the agglomeration process for the three regimes. Furthermore, the influence of temperature on reactive agglomeration significantly differed from that in agglomeration processes in which the binder was non-reactive. 展开更多
关键词 REGIME map DRY NEUTRALIZATION AGGLOMERATION non-reactive particles
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Non-linear Maps on Borel Subalgebras of Simple Lie Algebras Preserving Abelin Ideals
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作者 赵延霞 王登银 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第4期615-623,共9页
Let g be a complex simple Lie algebra of rank ι, b the standard Borel subalgebra. An invertible map on Ь is said to preserve abelian ideals if it maps each abelian ideal to some such ideal of the same dimension. In ... Let g be a complex simple Lie algebra of rank ι, b the standard Borel subalgebra. An invertible map on Ь is said to preserve abelian ideals if it maps each abelian ideal to some such ideal of the same dimension. In this article, by using some results of Chevalley groups, the theory of root systems and root space decomposition, the author gives an explicit description on such maps of Ь. 展开更多
关键词 simple Lie algebra abelian ideal non-linear map
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Non-linear Invertible Maps that Preserve Staircase Subalgebras
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作者 ZHAO YAN-XIA XIA YU-LING 《Communications in Mathematical Research》 CSCD 2012年第3期265-274,共10页
Let g be the general linear Lie algebra consisting of all n x n matrices over a field F and with the usual bracket operation {x, y} =xy - yx. An invertible map φ : g →g is said to preserve staircase subalgebras if ... Let g be the general linear Lie algebra consisting of all n x n matrices over a field F and with the usual bracket operation {x, y} =xy - yx. An invertible map φ : g →g is said to preserve staircase subalgebras if it maps every staircase subalgebra to some staircase subalgebra of the same dimension. In this paper, we devote to giving an explicit description on the invertible maps on g that preserve staircase subalgebras. 展开更多
关键词 general linear Lie algebra staircase subalgebra non-linear map
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An Adaptive Non-Linear Map and Its Application
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作者 YAN Xuefeng 《Wuhan University Journal of Natural Sciences》 CAS 2006年第3期572-576,共5页
A novel adaptive non-linear mapping (ANLM), integrating an adaptive mapping error (AME) with a chaosgenetic algorithm (CGA) including chaotic variable, was proposed to overcome the deficiencies of non-linear map... A novel adaptive non-linear mapping (ANLM), integrating an adaptive mapping error (AME) with a chaosgenetic algorithm (CGA) including chaotic variable, was proposed to overcome the deficiencies of non-linear mapping (NLM). The value of AME weight factor is determined according to the relative deviation square of distance between the two mapping points and the corresponding original objects distance. The larger the relative deviation square between two distances is, the larger the value of the corresponding weight factor is. Due to chaotic mapping operator, the evolutional process of CGA makes the individuals of subgenerations distributed ergodieally in the defined space and circumvents the premature of the individuals of subgenerations. The comparison results demonstrated that the whole performance of CGA is better than that of traditional genetic algorithm. Furthermore, a typical example of mapping eight-dimenslonal olive oil samples onto two-dimensional plane was employed to verify the effectiveness of ANLM. The results showed that the topology-preserving map obtained by ANLM can well represent the classification of original objects and is much better than that obtained by NLM. 展开更多
关键词 adaptive non-linear map topology- preserving mapping error chaotic variable genetic algorithm cluster
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New Necessary Conditions for a Fixed-Point of Maps in Non-Metric Spaces
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作者 Ivan Raykov 《Advances in Pure Mathematics》 2022年第10期561-564,共4页
Our purpose is to introduce new necessary conditions for a fixed point of maps on non-metric spaces. We use a contraction map on a metric topological space and a lately published definition of limit of a function betw... Our purpose is to introduce new necessary conditions for a fixed point of maps on non-metric spaces. We use a contraction map on a metric topological space and a lately published definition of limit of a function between the metric topological space and the non-metric topological space. Then we show that we can create a function h on the non-metric space Y, h :Y →Y and present necessary conditions for a fixed point of this map on this map on Y. Therefore, this gives an opportunity to take a best conclusion in some sense, when non-metrizable matter is under consideration. 展开更多
关键词 Topological Space Compact Metric Space Fixed Point Contraction map non-Metric Space
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Interplay of Quantum Stochastic and Dynamical Maps to Discern Markovian and Non-Markovian Transitions
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作者 A. R. Usha Devi A. K. Rajagopal +1 位作者 S. Shenoy R. W. Rendell 《Journal of Quantum Information Science》 2012年第3期47-54,共8页
It is known that the dynamical evolution of a system, from an initial tensor product state of system and environment, to any two later times, t1, t2 (t2 > t1), are both completely positive (CP) but in the intermedi... It is known that the dynamical evolution of a system, from an initial tensor product state of system and environment, to any two later times, t1, t2 (t2 > t1), are both completely positive (CP) but in the intermediate times between t1 and t2 it need not be CP. This reveals the key to the Markov (if CP) and non Markov (if it is not CP) avataras of the intermediate dynamics. This is brought out here in terms of the quantum stochastic map A and the associated dynamical map B—without resorting to master equation approaches. We investigate these features with four examples which have entirely different physical origins: 1) A two qubit Werner state map with time dependent noise parameter;2) Phenomenological model of a recent optical experiment (Nature Physics, 7, 931 (2011)) on the open system evolution of photon polarization;3) Hamiltonian dynamics of a qubit coupled to a bath of N qubits;4) Two qubit unitary dynamics of Jordan et al. (Phys. Rev. A 70, 052110 (2004) with initial product states of qubits. In all these models, it is shown that the positivity/negativity of the eigenvalues of intermediate time dynamical B map determines the Markov/non-Markov nature of the dynamics. 展开更多
关键词 Open System Dynamics non Markovianity Not COMPLETELY POSITIVE mapS
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Non-Linear Effects in Optical Systems by Lie Algebra and Symplectic Mapping
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作者 Víctor M. Castañ o 《Journal of Modern Physics》 CAS 2022年第11期1314-1323,共10页
The use of signals of different frequencies determines the geometrical deviation with respect to the optical axes of a given beam. This angle can be determined by Sympletic Map (SM), a powerful and simple mathematical... The use of signals of different frequencies determines the geometrical deviation with respect to the optical axes of a given beam. This angle can be determined by Sympletic Map (SM), a powerful and simple mathematical tool for the characterization and construction of images in Geometrical Optics. The Sympletic Map constitutes a Lie Group, with an algebra associated: the Lie Algebra. In general, the SM can be expressed as an infinite series, where each term corresponds to different contributions produced by the optical devices that constitute the optical system (lenses, apertures, bandwidth cutoff, etc.). The level of correction to be performed on the image to recover the original object is clear and controllable by SM. This formalism can be extended easily to physical optics to describe diffraction and interference phenomena. 展开更多
关键词 Symplectic mapping Geometrical Optics non-Linear Effects
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Characterization and Fine Mapping of Non-panicle Mutant (nop) in Rice
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作者 Wu Kun RAO Yu-chun +7 位作者 Hu Jiang ZHU Guan-lin ZHANG Guang-hen Hu Xin-ming Guo Long-biao WANG Yong-hong QIAN Qian ZENG Da-li 《Rice science》 SCIE 2009年第3期165-172,共8页
A mutant of panicle differentiation in rice called non-panicle (nop) was discovered in the progeny of a cross between 93-11 and Nipponbare. The mutant exhibits normal plant morphology but has apparently few tillers.... A mutant of panicle differentiation in rice called non-panicle (nop) was discovered in the progeny of a cross between 93-11 and Nipponbare. The mutant exhibits normal plant morphology but has apparently few tillers. The most striking change in nop is that its panicle differentiation is blocked, with masses of fluffy bract nodes generate from the positions where rachis branches normally develop in wild-type plants. Genetic analysis suggests that nop is controlled by a single recessive gene, which is temporarily named Nop(t). Based on its mutant phenotype, Nop(t) represents a key gene controlling the initiation of inflorescence differentiation, By using simple sequence repeat markers and sequence tagged site markers, Nop(t) gene was fine mapped in a 102-kb interval on the long arm of chromosome 6. These results will facilitate the positional cloning and functional studies of the gene. 展开更多
关键词 non-panicle gene panicle differentiation fine mapping rice (Oryza sativa)
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Non-Traveling Wave Solutions for the (1 + 1)-Dimensional Burgers System by Riccati Equation Mapping Approach
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作者 Ruiyang Xu Songhua Ma 《Applied Mathematics》 2013年第10期123-125,共3页
Starting from the symbolic computation system Maple and Riccati equation mapping approach and a linear variable separation approach, a new family of non-traveling wave solutions of the (1 + 1)-dimensional Burgers syst... Starting from the symbolic computation system Maple and Riccati equation mapping approach and a linear variable separation approach, a new family of non-traveling wave solutions of the (1 + 1)-dimensional Burgers system is derived. 展开更多
关键词 RICCATI Equation mapPING APPROACH Linear Variable Separation APPROACH BURGERS SYSTEM non-Traveling Wave Solutions
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NON-WANDERING SET OF A CONTINUOUS GRAPH MAP
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作者 GuRongbao SunTaixiang ZhengTingting 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第4期477-481,共5页
The non-wandering set Ω(f) for a graph map f is investigated. It is showed that Ω(f) is contained in the closure of the set ER(f) of eventually recurrent points of f and ω-limit set ω(Ω(f)) of Ω(f) is containe... The non-wandering set Ω(f) for a graph map f is investigated. It is showed that Ω(f) is contained in the closure of the set ER(f) of eventually recurrent points of f and ω-limit set ω(Ω(f)) of Ω(f) is contained in the closure of the set R(f) of recurrent points of f. 展开更多
关键词 graph map recurrent point eventually recurrent point ω-limit set non-wandering set
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同步记录无损伤心内、外膜心肌MAP对比研究 被引量:2
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作者 肖业伟 何光凤 +3 位作者 杭永伦 刘希秀 冯志强 盘强文 《中国现代医生》 2008年第31期49-50,共2页
目的建立无损伤同步记录心内外膜心肌MAP技术,比较内外膜MAP差异,更有效的探讨心律失常机制。方法15只家兔,在心肌缺血背景下致心律失常前后分别记录内外膜MAP各项观察指标,作对照比较。结果在心律失常前后,内外膜振幅APD90比较,差异不... 目的建立无损伤同步记录心内外膜心肌MAP技术,比较内外膜MAP差异,更有效的探讨心律失常机制。方法15只家兔,在心肌缺血背景下致心律失常前后分别记录内外膜MAP各项观察指标,作对照比较。结果在心律失常前后,内外膜振幅APD90比较,差异不具有统计学意义(P>0.05);但心律失常前后内外膜间比较,APD50差异具有统计学意义(P<0.05),且外膜APD50在心律失常前后自身比较,统计学有显著差异(P<0.05)。结论成功建立同步记录无损伤心内外膜心肌MAP模型,为探讨心律失常机制建立良好实验平台。 展开更多
关键词 无损伤 心内外膜 map
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基于MAP-MRF框架的复杂情况下多运动目标检测 被引量:1
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作者 万琴 王耀南 +2 位作者 刘星平 林国汉 余洪山 《仪器仪表学报》 EI CAS CSCD 北大核心 2014年第8期1869-1874,共6页
目标检测问题是视频监控系统中的关键问题,在监控场景复杂多变时,非参数方法是背景模型建模的重要方法,但传统的基于核密度带宽的非参数方法没有考虑像素之间的上下文关联性。本文提出建立目标检测问题的最大后验概率——马尔可夫随机场... 目标检测问题是视频监控系统中的关键问题,在监控场景复杂多变时,非参数方法是背景模型建模的重要方法,但传统的基于核密度带宽的非参数方法没有考虑像素之间的上下文关联性。本文提出建立目标检测问题的最大后验概率——马尔可夫随机场(MAP-MRF)框架,首先确定先验概率的能量函数,再确定条件概率及其能量函数,从而得到后验能量函数,采用蚁群算法迭代计算后验能量函数,获得像素标记的最优化结果即实现目标检测。在多个监控视频上的实验结果表明,本方法能大大提高复杂背景下的目标检测性能。 展开更多
关键词 视频监控 多目标检测 非参数方法
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高铝MAP沸石的非自发结晶动力学研究 被引量:2
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作者 谷名学 施林海 +2 位作者 顾诚 姜慧文 龙英才 《化学学报》 SCIE CAS CSCD 北大核心 1999年第6期603-608,共6页
在强碱性水溶液体系中,以水玻璃为硅源,以铝酸钠为铝源,在类质同晶高硅P沸石晶种导向作用下,反应物中自发生成的A型沸石可转晶为纯相高铝MAP沸石.升高反应温度有利于提高产物的结晶度.由不同温度下的晶化曲线计算出MAP沸石表观生长活化... 在强碱性水溶液体系中,以水玻璃为硅源,以铝酸钠为铝源,在类质同晶高硅P沸石晶种导向作用下,反应物中自发生成的A型沸石可转晶为纯相高铝MAP沸石.升高反应温度有利于提高产物的结晶度.由不同温度下的晶化曲线计算出MAP沸石表观生长活化能为59.6kJ·mol^(-1).不用晶种时,同一反应物体系结晶产物为单一的A型沸石.在该反应物体系中,A型沸石的成核活化能与生长活化能分别为40.3和50.7 kJ·mol^(-1).MAP高的生长活化能以及A型沸石相对低的成核与生长活化能揭示合成MAP沸石时使用晶种的原因. 展开更多
关键词 map沸石 沸石 洗涤剂 结晶动力学 助剂
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基于层次分析(AHP)和风险坐标图(R-Map)的民办高等学校办学风险评价 被引量:5
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作者 王旭 《当代教育论坛》 2013年第3期64-69,共6页
文章按照风险界定、风险识别、风险评价的思路对现阶段民办高等学校办学风险进行定量分析。通过实地调研,准确识别民办高等学校办学过程中的政策风险、市场风险、管理风险、质量风险与财务风险,并以此构建风险层次模型。为科学评价风险... 文章按照风险界定、风险识别、风险评价的思路对现阶段民办高等学校办学风险进行定量分析。通过实地调研,准确识别民办高等学校办学过程中的政策风险、市场风险、管理风险、质量风险与财务风险,并以此构建风险层次模型。为科学评价风险,利用层次分析法(AHP)确定各类风险的权重,并引入风险坐标图(R-Map)科学直观地评价各类办学风险的强度。 展开更多
关键词 层次分析法 风险坐标图 民办高等学校 办学风险
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改进麻雀搜索算法的四旋翼无人机路径规划
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作者 朱易凡 裘旭冬 李硕 《传感器与微系统》 北大核心 2025年第1期141-145,151,共6页
针对麻雀搜索算法(SSA)容易陷入局部最优、求解精度不高和收敛速度较慢的问题,本文提出一种非线性正态差分SSA(NLN-DSSA)。采用改进Circle混沌映射初始化麻雀种群,提升种群多样性,提高算法在迭代开始时的全局搜索能力;引入非线性正态分... 针对麻雀搜索算法(SSA)容易陷入局部最优、求解精度不高和收敛速度较慢的问题,本文提出一种非线性正态差分SSA(NLN-DSSA)。采用改进Circle混沌映射初始化麻雀种群,提升种群多样性,提高算法在迭代开始时的全局搜索能力;引入非线性正态分布系数来控制发现者的搜索步长和收敛速度,平衡全局搜索和局部开发能力;引进差分变异策略增加种群的多样性,帮助算法跳出局部最优。在5个基准测试函数上寻优实验,结果表明:NLN-DSSA具有更好的收敛速度和寻优精度。最后将NLN-DSSA应用到无人机路径规划上,证明改进算法的有效性和实用性。 展开更多
关键词 麻雀搜索算法 Circle混沌映射 非线性正态差分 差分变异 路径规划
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基于非局部挖掘再现网络的自监督无人机航拍图像超分辨率重建
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作者 张永挺 林江涛 +1 位作者 谢绍敏 刘剑 《测绘通报》 北大核心 2025年第1期16-21,共6页
近年来,深度卷积神经网络在无人机航拍图像超分辨率任务中应用,使得无人机航拍图像超分辨率的性能取得了巨大的提升。然而,基于卷积神经网络的超分辨率方法依赖于特定的训练数据集,这种数据集通常是通过固定双三次采用内核对图像进行下... 近年来,深度卷积神经网络在无人机航拍图像超分辨率任务中应用,使得无人机航拍图像超分辨率的性能取得了巨大的提升。然而,基于卷积神经网络的超分辨率方法依赖于特定的训练数据集,这种数据集通常是通过固定双三次采用内核对图像进行下采样构建的。当处理后的图像不满足这种“理想”情况时,其性能将急剧下降。因此,本文提出一种基于非局部挖掘再现网络的自监督无人机航拍图像超分辨率重建方法(NLMRN)。NLMRN只需要一张输入图像,无需对外部数据集进行预训练。它利用无人机航拍图像内部信息的非局部再现性,对输入图像本身进行下采样,以获得较低分辨率的图像并进行训练。为了更好地学习非局部重复特征,使用非局部上下文挖掘块(NLCM)建立非局部区域间的关系,并选择全局特征图的子集补充每个特定位置,以获得精确细节和纹理的重建。NLCM有效弥补了卷积运算一次只能处理一个局部邻域的不足。通过大量的试验验证,NLMRN在处理“非理想”条件下的无人机航拍图像时,明显优于其他先进的超分辨率方法。 展开更多
关键词 无人机航拍 超分辨率 非局部再现性 全局特征图
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一种采用非均匀量化的近似Log-MAP算法 被引量:2
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作者 周继宇 张雅奇 徐伯庆 《无线电通信技术》 2012年第1期29-31,共3页
为了简化Log-MAP算法、减小其硬件查表实现时所占用的外存储单元,采用了非均匀量化的方法分别对Log-MAP算法中的校正函数进行两电平和五电平近似,从而得到相应的量化函数。并将该量化函数用于LTE Turbo译码器,在AWGN信道上进行软迭代译... 为了简化Log-MAP算法、减小其硬件查表实现时所占用的外存储单元,采用了非均匀量化的方法分别对Log-MAP算法中的校正函数进行两电平和五电平近似,从而得到相应的量化函数。并将该量化函数用于LTE Turbo译码器,在AWGN信道上进行软迭代译码仿真。仿真结果表明,两电平和五电平非均匀量化的近似Log-MAP算法将Max-Log-MAP算法的译码性能提高了0.2~0.3 dB,与原Log-MAP算法性能接近,但却能大大减少查表时需要检索的数据量。 展开更多
关键词 TURBO译码 Log—map算法 校正函数 非均匀量化 软迭代译码
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基于MapInfo的非空间属性数据专题地图设计实现研究 被引量:1
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作者 李华蓉 徐兮 《城市勘测》 2008年第5期130-132,共3页
地图是表达地理信息最传统、最恰当的方式,广义的地理信息不仅包括自然地理信息,也包括社会地理信息,而社会地理信息数据大多是非空间属性数据,因此非空间属性数据地图的设计研究即成为必需。本文运用MapInfo软件强大的(专题)地图的制... 地图是表达地理信息最传统、最恰当的方式,广义的地理信息不仅包括自然地理信息,也包括社会地理信息,而社会地理信息数据大多是非空间属性数据,因此非空间属性数据地图的设计研究即成为必需。本文运用MapInfo软件强大的(专题)地图的制作功能,处理高等教育研究成果数据,化枯燥数表为生动直观易读的图形,在研究非空间的纯属性数据之专题地图设计实现方面,做出切实有益的尝试。 展开更多
关键词 非空间属性数据 maplnfo软件 专题地图
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磁共振T2-Map的单、双指数拟合方法 被引量:8
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作者 李雅芬 牛爱青 康立丽 《中国医学影像技术》 CSCD 北大核心 2010年第2期347-350,共4页
目的探讨MR图像单指数和双指数拟合的T2-Map方法,获得每个像素点的T2信息。方法对不同TE条件下的一系列MR图像利用单、双指数拟合方法得到T2-Map图像。采用线性拟合和非线性回归方法实现对MR图像的每个像素点的单指数拟合和定点双指数拟... 目的探讨MR图像单指数和双指数拟合的T2-Map方法,获得每个像素点的T2信息。方法对不同TE条件下的一系列MR图像利用单、双指数拟合方法得到T2-Map图像。采用线性拟合和非线性回归方法实现对MR图像的每个像素点的单指数拟合和定点双指数拟合,得到T2-Map图像;上述计算过程是在MATLAB平台上开发T2-Map的计算软件,根据应用需求设计并实现计算、显示和存储等功能。结果得到了单、双指数拟合方法的T2-Map计算软件,可用于计算不同组织的T2值,得到T2-Map。结论利用单指数线性拟合方法得到T2-Map图像方便、快捷,但不能很好地反映一些组织成分混合较多的区域;在出现组织明显混合的情形时,双指数拟合的方法可以计算出两个不同的T2值,使得分析结果更加精确,但是计算速度较慢,双指数T2-Map是单指数T2-Map计算方法的有益补充。 展开更多
关键词 磁共振成像 T2-map 线性拟合 非线性回归
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