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Spatial distribution order parameter prediction of collective system using graph network
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作者 赵慧敏 王瑞 +1 位作者 赵偲 郑文 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期566-572,共7页
In the past few decades, the study of collective motion phase transition process has made great progress. It is also important for the description of the spatial distribution of particles. In this work, we propose a n... In the past few decades, the study of collective motion phase transition process has made great progress. It is also important for the description of the spatial distribution of particles. In this work, we propose a new order parameter φ to quantify the degree of order in the spatial distribution of particles. The results show that the spatial distribution order parameter can effectively describe the transition from a disorderly moving phase to a phase with a coherent motion of the particle distribution and the same conclusion could be obtained for systems with different sizes. Furthermore, we develop a powerful molecular dynamic graph network(MDGNet) model to realize the long-term prediction of the self-propelled collective system solely from the initial particle positions and movement angles. Employing this model, we successfully predict the order parameters of the specified time step. And the model can also be applied to analyze other types of complex systems with local interactions. 展开更多
关键词 order parameter graph network collective system active matter
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A tentative model for the explanation of B?th law using the order parameter of seismicity in natural time 被引量:1
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作者 Konstantina A. Papadopoulou Efthimios S. Skordas Nicholas V. Sarlis 《Earthquake Science》 CSCD 2016年第6期311-319,共9页
Using the order parameter of seismicity defined in natural time, we suggest a simple model for the expla- nation of Bath law, according to which a mainshock differs in magnitude from its largest aftershock by approxim... Using the order parameter of seismicity defined in natural time, we suggest a simple model for the expla- nation of Bath law, according to which a mainshock differs in magnitude from its largest aftershock by approximately 1.2 regardless of the mainshock magnitude. In addition, the validity of Bath law is studied in the Global Centroid Moment Tensor catalogue by using two different aftershock definitions. It is found that the mean of this difference, when considering all the pairs mainshock-largest aftershock, does not markedly differ from 1.2 and the corresponding distributions do not depend on the mainshock's magnitude threshold in a statistically significant manner. Finally, the analysis of the cumulative distribution functions provides evidence in favour of the proposed model. 展开更多
关键词 Bath law . Aftershocks .order parameter .Natural time
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A novel approach to topological defects in a vector order parameter system
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作者 任继荣 戎树军 朱涛 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第7期2901-2904,共4页
Based on Duan's topological current theory,we propose a novel approach to study the topological properties of topological defects in a two-dimensional complex vector order parameter system.This method shows explicitl... Based on Duan's topological current theory,we propose a novel approach to study the topological properties of topological defects in a two-dimensional complex vector order parameter system.This method shows explicitly the fine topological structure of defects.The branch processes of defects in the vector order parameter system have also been investigated with this method. 展开更多
关键词 topological defects order parameter topological current branch processes
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Temperature dependence of ratio between dielectric anisotropy and order parameter in fluorinated nematic liquid crystals
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作者 马恒 孙瑞芝 +1 位作者 李振新 刘玉芳 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第1期255-258,共4页
Temperature dependence of ratio between dielectric anisotropy and order parameter of fluorinated nematic liquid crystal is investigated by using a semi-empirical molecular orbital package that can accurately calculate... Temperature dependence of ratio between dielectric anisotropy and order parameter of fluorinated nematic liquid crystal is investigated by using a semi-empirical molecular orbital package that can accurately calculate an angle between molecular dipole moment and long axis. We optimize the molecular conformations with three semi-empirical Hamiltonians AM1, PM3 and PM5, and then make a comparison between computational results and experimental measurements. It is shown that the results obtained from AM1 method are in good agreement with the measurements. The present study offers an applicable method to predict the dielectric properties of liquid crystal material. 展开更多
关键词 dielectric anisotropy order parameter FLUORINE nematic liquid crystal
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Order parameters and synchronization of FitzHugh-Nagumo small-world networks
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作者 李延龙 马军 +1 位作者 张巍 刘延君 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第10期4598-4602,共5页
This paper numerically investigates the order parameter and synchronisation in the small world connected FitzHugh-Nagumo excitable systems. The simulations show that the order parameter continuously decreases with inc... This paper numerically investigates the order parameter and synchronisation in the small world connected FitzHugh-Nagumo excitable systems. The simulations show that the order parameter continuously decreases with increasing D, the quality of the synchronisation worsens for large noise intensity. As the coupling intensity goes up, the quality of the synchronisation worsens, and it finds that the larger rewiring probability becomes the larger order parameter. It obtains the complete phase diagram for a wide range of values of noise intensity D and control parameter g. 展开更多
关键词 order parameter small world network noise
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Polarizabilities and Orientational Order Parameter in N-(p-n-Ethoxybenzylidene)- p-n-Alkoxy Anilines, 2O.Om LC Compounds
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作者 Putcha Srinivasa Sastry Chintalapati Srinivas +1 位作者 Pokkunuri Pardhasaradhi Venkata Gopala Krishna Murthy Pisipati 《Journal of Surface Engineered Materials and Advanced Technology》 2016年第3期134-148,共16页
n.m, n.Om, nO.m and nO.Om compounds play an important role in the fundamental and applied aspects. As a part of our systematic studies of the above homologous series regarding the synthesis, characterization and phase... n.m, n.Om, nO.m and nO.Om compounds play an important role in the fundamental and applied aspects. As a part of our systematic studies of the above homologous series regarding the synthesis, characterization and phase transition studies, here the authors report the polarizabilities and orientational order parameter, S in N-(p-n-ethoxybenzylidene)-p-n-alkoxy anilines, 2O.Om with m = 3 to 10 liquid crystalline compounds except with m = 5 which has been already published. The rest of the compounds exhibit the nematic LC phase except with m = 10 which shows the smectic-C phase along the nematic phase which is originally not detected by Godzwon et al. But the author’s observations with TM and differential scanning calorimeter have shown the existence on SmC phase in addition to nematic phase. Further, SmC is clarified using the histogram technique whose details are given below and are published elsewhere. The orientstonal order parameter, S is estimated using different methods and compared with the value obtained from birefringence, δn = (n<sub>e</sub> – n<sub>o</sub>) where no field model is used. It is observed in these compounds case as in other LC compounds Vuks isotropic model is favored compared to that of anisotropic model proposed by Neugebauer. 展开更多
关键词 Orientstonal order parameter S 2O.Om LC Compounds Vuks Isotropic Model Neugebauer Anisotropic Model Nematic Phase
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Order parameter analysis of synchronization transitions on star networks 被引量:1
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作者 Hong-Bin Chen Yu-Ting Sun +2 位作者 Jian Gao Can Xu Zhi-Gang Zheng 《Frontiers of physics》 SCIE CSCD 2017年第6期11-20,共10页
The collective behaviors of populations of coupled oscillators have attracted significant attention in recent years. In this paper, an order parameter approach is proposed to study the low-dimensional dynamical mechan... The collective behaviors of populations of coupled oscillators have attracted significant attention in recent years. In this paper, an order parameter approach is proposed to study the low-dimensional dynamical mechanism of collective synchronizations, by adopting the star-topology of coupled oscil- lators as a prototype system. The order parameter equation of star-linked phase oscillators can be obtained in terms of the Watanabe--Strogatz transformation, Ott--Antonsen ansatz, and the ensem- ble order parameter approach. Different solutions of the order parameter equation correspond to the diverse collective states, and different bifurcations reveal various transitions among these collective states. The properties of various transitions in the star-network model are revealed by using tools of nonlinear dynamics such as time reversibility analysis and linear stability analysis. 展开更多
关键词 Kuramoto model SYNCHRONIZATION order parameter Ott-Antonsen ansatz star network
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Universal order-parameter and quantum phase transition for two-dimensional q-state quantum Potts model
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作者 代艳伟 李生好 陈西浩 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第7期163-168,共6页
We investigate quantum phase transitions for q-state quantum Potts models(q=2,3,4)on a square lattice and for the Ising model on a honeycomb lattice by using the infinite projected entangled-pair state algorithm with ... We investigate quantum phase transitions for q-state quantum Potts models(q=2,3,4)on a square lattice and for the Ising model on a honeycomb lattice by using the infinite projected entangled-pair state algorithm with a simplified updating scheme.We extend the universal order parameter to a two-dimensional lattice system,which allows us to explore quantum phase transitions with symmetry-broken order for any translation-invariant quantum lattice system of the symmetry group G.The universal order parameter is zero in the symmetric phase,and it ranges from zero to unity in the symmetry-broken phase.The ground-state fidelity per lattice site is computed,and a pinch point is identified on the fidelity surface near the critical point.The results offer another example highlighting the connection between(i)critical points for a quantum many-body system undergoing a quantum phase-transition and(ii)pinch points on a fidelity surface.In addition,we discuss three quantum coherence measures:the quantum Jensen–Shannon divergence,the relative entropy of coherence,and the l1norm of coherence,which are singular at the critical point,thereby identifying quantum phase transitions. 展开更多
关键词 quantum phase transitions universal order parameter FIDELITY
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Shape phase transition in the odd Sm nuclei: effective order parameter and odd–even effect
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作者 张宇 关鑫 +3 位作者 王印 左岩 包丽娜 潘峰 《Chinese Physics C》 SCIE CAS CSCD 2015年第10期48-54,共7页
Some binding energy related quantities serving as effective order parameters have been used to analyze the shape phase transition in the odd Sm nuclei. It is found that the signals of phase transition in the odd Sm nu... Some binding energy related quantities serving as effective order parameters have been used to analyze the shape phase transition in the odd Sm nuclei. It is found that the signals of phase transition in the odd Sm nuclei are greatly enhanced in contrast to the even Sm nuclei. A further analysis shows that the transitional behaviors related to pairing in the Sm nuclei can be well described by the mean field plus pairing interaction model, with a monotonic decrease in the pairing strength G. 展开更多
关键词 shape phase transition effective order parameter odd even effects
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CONSTITUTIVE EQUATION WITH ORDERED PARAMETERS FOR VISCOELASTIC MATERIAL CONTAINING DEFECTS 被引量:1
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作者 Yuan Longwei(Institute of Rheological Mechanics,Xiangtan University,Xiangtan 411105,China) 《Acta Mechanica Solida Sinica》 SCIE EI 1997年第1期11-27,共17页
Based on the experimental results of local temperature field formed in the evolution period of defects, the defect field is defined by this internal temperature field. The evolutionary processes of statistically corre... Based on the experimental results of local temperature field formed in the evolution period of defects, the defect field is defined by this internal temperature field. The evolutionary processes of statistically correlative meso-scopic defects are analysed with the growth rate and nucleation rate of the meso-defect, and it is deemed that the dynamic failure process of the viscoelastic material with defects can be quantitatively described by the normal method of the procedure of heat wave transmission. The defect field is regarded as a complex system of the union of the real sets and null sets, its main characteristics depending on the stratum hypothesis about the activities of the subsystems of the highest stratum described by ordered parameters. The fluctuation of ordered parameters is demonstrated by means of the projection operator method. The constitutive equation with ordered parameters for the meso-defect evolutionary state of viscoelastic material with defects is deduced from the nonlinear rheological dynamic approach, and its solution is obtained. 展开更多
关键词 rheology of bodies with defects constitutive equation local temperature field heat waves ordered parameter stratum system
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SPECTRUM DISTRIBUTION OF THE SEDOND ORDER GENERALIZED DISTRIBUTED PARAMETER SYSTEMS 被引量:2
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作者 葛照强 朱广田 马勇镐 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第10期1224-1232,共9页
Spectrum distribution of the second order generalized distributed parameter system was discussed via the functional analysis and operator theory in Hilbert space. The solutions of the problem and the constructive expr... Spectrum distribution of the second order generalized distributed parameter system was discussed via the functional analysis and operator theory in Hilbert space. The solutions of the problem and the constructive expression of the solutions are given by the generalized inverse one of bounded linear operator. This is theoretically important for studying the stabilization and asymptotic stability of the second order generalized distributed parameter system. 展开更多
关键词 second order generalized distributed parameter system spectrum distribution Hilbert space generalized inverse one of bounded linear operatiors
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THEORY OF INTRAMOLECULAR ORIENTATIONAL ORDER OF MESOGENIC UNITS IN MC-LCPS AND ITS APPLICATION
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作者 王晓工 刘德山 周其庠 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1993年第4期17-25,共9页
New concepts such as intramolecular orientational order parameter and corresponding model as well as theory were proposed to describe the intramolecular orientation of mesogenic units in the liquid crystalline polymer... New concepts such as intramolecular orientational order parameter and corresponding model as well as theory were proposed to describe the intramolecular orientation of mesogenic units in the liquid crystalline polymer chains. The relationship between the intramolecular orientational order parameter and the molecular geometrical parameters such as the bond angle, the bond rotational angle and the rotational potential energy of chemical bonds was deduced. A significant even-odd oscillation of the intramolecular orientational order parameter of LCPs with different length of flexible spacer was found and rationally related to even-odd zig-zag manner of transition properties The verification and application of the theory are also discussed. The isotropic transition temperature predicted by the theory is shown to be in favourable agreement with the experiments. 展开更多
关键词 Liquid crystal polymer Intramolecular orientation order parameter Theory.
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考虑新能源高阶不确定性的交直流混联电网静态电压稳定裕度计算
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作者 张芸烽 林舜江 +2 位作者 杨悦荣 刘万彬 刘明波 《高电压技术》 EI CAS CSCD 北大核心 2024年第4期1631-1644,共14页
随着大量新能源场站接入交直流混联电网,系统的静态电压稳定裕度(static voltage stability margin,SVSM)水平具有很大的不确定性,需要研究考虑新能源场站高阶不确定性的交直流混联电网SVSM计算方法。针对此问题,首先建立了交直流混联电... 随着大量新能源场站接入交直流混联电网,系统的静态电压稳定裕度(static voltage stability margin,SVSM)水平具有很大的不确定性,需要研究考虑新能源场站高阶不确定性的交直流混联电网SVSM计算方法。针对此问题,首先建立了交直流混联电网SVSM计算模型,模型中考虑了直流换流站控制方式随负荷增长的切换;采用概率盒模型描述风速与光照强度的随机波动,提出了改进区间半不变量法以获得更准确的SVSM概率盒,该方法通过K-means++聚类算法将随机变量样本划分为多个波动范围较小的样本集,以降低半不变量的线性化计算带来的误差;并结合Gram-Charlier级数展开和概率加权和计算得到考虑新能源场站高阶不确定性的系统SVSM概率盒。通过对修改的IEEE-39节点交直流系统和南方电网两个算例的分析,并与区间半不变量法和双层蒙特卡洛法比较,验证了所提出方法获得的SVSM概率盒具有较高的计算精度和效率。 展开更多
关键词 新能源 交直流混联电网 高阶不确定性 静态电压稳定裕度 参数化概率盒 改进区间半不变量法
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Unifying the theory of integration within normal-,Weyl- and antinormal-ordering of operators and the s-ordered operator expansion formula of density operators 被引量:2
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作者 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期41-47,共7页
By introducing the s-parameterized generalized Wigner operator into phase-space quantum mechanics we invent the technique of integration within s-ordered product of operators (which considers normally ordered, antino... By introducing the s-parameterized generalized Wigner operator into phase-space quantum mechanics we invent the technique of integration within s-ordered product of operators (which considers normally ordered, antinormally ordered and Weyl ordered product of operators as its special cases). The s-ordered operator expansion (denoted by s…s ) formula of density operators is derived, which isρ=2/1-s∫d^2β/π〈-β|ρ|β〉sexp{2/s-1(s|β|^2-β*α+βa-αα)}s The s-parameterized quantization scheme is thus completely established. 展开更多
关键词 s-parameterized generalized Wigner operator technique of integration within s-ordered product of operators s-ordered operator expansion formula s-parameterized quantization scheme
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Parameterization based on maximum curvature minimization model
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作者 BAN Jinjin ZHANG Caiming ZHOU Yuanfeng 《Computer Aided Drafting,Design and Manufacturing》 2013年第1期47-52,共6页
Parameterization is one of the key problems in the construction of a curve to interpolate a set of ordered points. We propose a new local parameterization method based on the curvature model in this paper. The new met... Parameterization is one of the key problems in the construction of a curve to interpolate a set of ordered points. We propose a new local parameterization method based on the curvature model in this paper. The new method determines the knots by mi- nimizing the maximum curvature of quadratic curve. When the knots by the new method are used to construct interpolation curve, the constructed curve have good precision. We also give some comparisons of the new method with existing methods, and our method can perform better in interpolation error, and the interpolated curve is more fairing. 展开更多
关键词 ordered data points quadratic curve CURVATURE parameterIZATION
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On the Cosmic Evolution of the Quantum Vacuum Using Two Variable G Models and Winterberg’s Thesis
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作者 Christopher Pilot 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第4期1134-1160,共27页
We work within a Winterberg framework where space, i.e., the vacuum, consists of a two component superfluid/super-solid made up of a vast assembly (sea) of positive and negative mass Planck particles, called planckion... We work within a Winterberg framework where space, i.e., the vacuum, consists of a two component superfluid/super-solid made up of a vast assembly (sea) of positive and negative mass Planck particles, called planckions. These material particles interact indirectly, and have very strong restoring forces keeping them a finite distance apart from each other within their respective species. Because of their mass compensating effect, the vacuum appears massless, charge-less, without pressure, net energy density or entropy. In addition, we consider two varying G models, where G, is Newton’s constant, and G<sup>-1</sup>, increases with an increase in cosmological time. We argue that there are at least two competing models for the quantum vacuum within such a framework. The first follows a strict extension of Winterberg’s model. This leads to nonsensible results, if G increases, going back in cosmological time, as the length scale inherent in such a model will not scale properly. The second model introduces a different length scale, which does scale properly, but keeps the mass of the Planck particle as, ± the Planck mass. Moreover we establish a connection between ordinary matter, dark matter, and dark energy, where all three mass densities within the Friedman equation must be interpreted as residual vacuum energies, which only surface, once aggregate matter has formed, at relatively low CMB temperatures. The symmetry of the vacuum will be shown to be broken, because of the different scaling laws, beginning with the formation of elementary particles. Much like waves on an ocean where positive and negative planckion mass densities effectively cancel each other out and form a zero vacuum energy density/zero vacuum pressure surface, these positive mass densities are very small perturbations (anomalies) about the mean. This greatly alleviates, i.e., minimizes the cosmological constant problem, a long standing problem associated with the vacuum. 展开更多
关键词 Winterberg Model Planck Particles Positive and Negative Mass Planck Particles Planckions Quantum Vacuum Space as a Superfluid/Supersolid Extended Models for Space Cosmological Constant Higgs Field as a Composite Particle Higgs Boson Inherent Length Scale for the Vacuum Dark Energy Cosmological Scaling Behavior for the Quantum Vacuum Variable G Models Extended Gravity Newton’s Constant as an order parameter High Energy Behavior for the Vacuum
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The s-parameterized Weyl-Wigner correspondence in the entangled form and its applications
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作者 范洪义 胡利云 袁洪春 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期52-57,共6页
Based on the theory of integration within s-ordering of operators and the bipartite entangled state representation we introduce s-parameterized Weyl-Wigner correspondence in the entangled form. Some of its application... Based on the theory of integration within s-ordering of operators and the bipartite entangled state representation we introduce s-parameterized Weyl-Wigner correspondence in the entangled form. Some of its applications in quantum optics theory are presented as well. 展开更多
关键词 s-parameterized Wigner operator s-parameterized Weyl-Wigner correspondence integration within s-ordered product of operators technique
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基于VC与APDL接口的气门参数化建模与有限元分析系统 被引量:5
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作者 李厚佳 卢平 刘佐民 《武汉理工大学学报(交通科学与工程版)》 2007年第2期325-327,363,共4页
基于ANSYS与VC接口实现气门参数化建模与有限元分析系统,利用VC封装ANSY S的二次开发工具APDL命令流,使气门参数化,并将APDL命令流文件自动读入ANSYS进行气门有限元分析.系统建立的友好参数输入界面,可直接输入气门结构参数,从而建立气... 基于ANSYS与VC接口实现气门参数化建模与有限元分析系统,利用VC封装ANSY S的二次开发工具APDL命令流,使气门参数化,并将APDL命令流文件自动读入ANSYS进行气门有限元分析.系统建立的友好参数输入界面,可直接输入气门结构参数,从而建立气门的有限元模型,替代ANSYS人机交互的GUI方式,从而避免了气门建模与分析转换过程中的信息流失,提高了气门建模的工作效率有限元分析的可靠性. 展开更多
关键词 APDL命令流 VC 气门参数化
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二阶线性系统全维PI观测器的参数化设计 被引量:6
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作者 王国胜 吕强 段广仁 《控制与决策》 EI CSCD 北大核心 2007年第3期345-348,共4页
基于一类广义Sylvester矩阵方程的解,提出了二阶线性系统的全维PI观测器设计参数化方法,给出了该类观测器的增益矩阵和左特征向量矩阵的参数化表达式.该观测器设计的参数化方法直接基于二阶线性系统的参数矩阵,不涉及系统的变换或增广.... 基于一类广义Sylvester矩阵方程的解,提出了二阶线性系统的全维PI观测器设计参数化方法,给出了该类观测器的增益矩阵和左特征向量矩阵的参数化表达式.该观测器设计的参数化方法直接基于二阶线性系统的参数矩阵,不涉及系统的变换或增广.数值例子表明了所提方法的简单有效性. 展开更多
关键词 二阶线性系统 比例积分观测器 参数化 自由度
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基于Pro/E的有序抛秧机三维参数化造型设计 被引量:9
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作者 李建平 魏宝刚 +1 位作者 杨晨东 赵匀 《农业机械学报》 EI CAS CSCD 北大核心 2006年第5期60-62,共3页
有序抛秧机是一种将水稻钵苗按一定行株距抛入田间的机具,传统的设计方法是利用平面二维图表示,不直观,不便于修改。应用P ro/E软件进行抛秧机三维参数化造型设计,通过改变尺寸参数可以方便地改变和修改零件的形状,直观地观察和分析整... 有序抛秧机是一种将水稻钵苗按一定行株距抛入田间的机具,传统的设计方法是利用平面二维图表示,不直观,不便于修改。应用P ro/E软件进行抛秧机三维参数化造型设计,通过改变尺寸参数可以方便地改变和修改零件的形状,直观地观察和分析整个机具的外形、零件间的相互位置关系,从三维造型可自动生成平面二维图纸,用于生产与加工。 展开更多
关键词 有序抛秧机 参数化造型 设计
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