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Synthesis and characterization of non-symmetrical liquid crystals containing a cholesteryl ester moiety 被引量:3
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作者 Duo Wei Zhang Wei Huang Guo Hui Pan Wan Li He Yu Bo Cao Jin Bao Guo Hui Cao Huai Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第5期562-565,共4页
In this paper, a series of chiral non-symmetrical liquid crystals (nBA-chol) consisting of a cholesteryl ester moiety as chiral entity and a biphenyl aromatic core with different terminal alkyl chain has been synthe... In this paper, a series of chiral non-symmetrical liquid crystals (nBA-chol) consisting of a cholesteryl ester moiety as chiral entity and a biphenyl aromatic core with different terminal alkyl chain has been synthesized and investigated for their liquid crystalline properties. Effects of numbers of methylene units in the terminal alkyl chain on the phase transition temperatures and on the temperature-dependent pitch lengths of the chiral liquid crystals have been studied. The long terminal alkyl chain tends to exhibit smectic A mesophases. The pitch lengths of the cholesteric mesophases of the chiral liquid crystals decrease with increasing temperature and with increasing numbers of methylene units in the terminal alkyl chain, respectively. 展开更多
关键词 Liquid crystals non-symmetrical CHIRAL MESOPHASE PITCH
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Research on the Control for the Planar Motor by Non-symmetric and Unilateral Driven 被引量:3
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作者 LI Xin, YANG Kaiming ZHU Yu YU Dongdong CUI Leqing 《中国电机工程学报》 EI CSCD 北大核心 2012年第27期I0004-I0004,180,共1页
与由四组线圈单元驱动方式相比,三组线圈单元驱动的平面电机属于单边非质心驱动模型。为提高平面电机系统的伺服性能,需要准确的力解耦模型以及有效的控制算法。由于实际中存在建模误差,如永磁体线圈加工误差引起的推力误差、气隙厚... 与由四组线圈单元驱动方式相比,三组线圈单元驱动的平面电机属于单边非质心驱动模型。为提高平面电机系统的伺服性能,需要准确的力解耦模型以及有效的控制算法。由于实际中存在建模误差,如永磁体线圈加工误差引起的推力误差、气隙厚度不均匀、外部不确定扰动等,使得基于名义模型的系统无法有效解耦。同时建模误差的存在使得闭环系统误差方程的等号右侧不为0,无法确保跟踪误差的收敛。因此,必须利用控制器对建模误差进行补偿。以三组线圈单元且x方向为单边非质心驱动的平面电机作为研究对象。为提高其轨迹跟踪与定位能力,提出一种非线性控制算法。在逆动力学控制算法的基础上增加鲁棒项,对建模误差进行有效补偿。采用李雅普诺夫(Lyapunov)理论证明了该算法的稳定性。实验结果表明,轨迹跟踪误差小于1.5μm,可见通过对建模误差的补偿,减小了多自由度间耦合作用对运动精度的影响,提高了平面电机伺服性能。 展开更多
关键词 电动机驱动 平面电机 电机控制 非对称 反馈线性化 SISO系统 多输入多输出 定位系统
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Analysis of non-symmetrical flapping airfoils 被引量:2
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作者 W.B.Tay K.B.Lim 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第4期433-450,共18页
Simulations have been done to assess the lift, thrust and propulsive efficiency of different types of non-symmetrical airfoils under different flapping configurations. The variables involved are reduced frequency, Str... Simulations have been done to assess the lift, thrust and propulsive efficiency of different types of non-symmetrical airfoils under different flapping configurations. The variables involved are reduced frequency, Strouhal number, pitch amplitude and phase angle. In order to analyze the variables more efficiently, the design of experiments using the response surface methodology is applied. Results show that both the variables and shape of the airfoil have a profound effect on the lift, thrust, and efficiency. By using non- symmetrical airfoils, average lift coefficient as high as 2.23 can be obtained. The average thrust coefficient and efficiency also reach high values of 2.53 and 0.61, respectively. The lift production is highly dependent on the airfoil's shape while thrust production is influenced more heavily by the variables. Efficiency falls somewhere in between. Two-factor interac- tions are found to exist among the variables. This shows that it is not sufficient to analyze each variable individually. Vorticity diagrams are analyzed to explain the results obtained. Overall, the S1020 airfoil is able to provide relatively good efficiency and at the same time generate high thrust and lift force. These results aid in the design of a better ornithopter's wing. 展开更多
关键词 FLAPPING non-symmetrical Design ofexperiments Ornithopter AIRFOIL
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Multi-party dense coding in non-symmetric quantum channel 被引量:2
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作者 付长宝 夏岩 张寿 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第8期1682-1685,共4页
A three- and an (N+ 1)-party dense coding scheme in the case of non-symmetric Hilbert spaces of the particles of a quantum channel are investigated by using a multipartite entangled state. In the case of the (N ... A three- and an (N+ 1)-party dense coding scheme in the case of non-symmetric Hilbert spaces of the particles of a quantum channel are investigated by using a multipartite entangled state. In the case of the (N + 1)-party dense coding scheme, we show that the amount of classical information transmitted from N senders to one receiver is improved. 展开更多
关键词 non-symmetric Hilbert space dense coding unitary transformation
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Symmetric bursting behaviour in non-smooth Chua's circuit 被引量:2
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作者 季颖 毕勤胜 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期200-204,共5页
The dynamics of a non-smooth electric circuit with an order gap between its parameters is investigated in this paper. Different types of symmetric bursting phenomena can be observed in numerical simulations. Their dyn... The dynamics of a non-smooth electric circuit with an order gap between its parameters is investigated in this paper. Different types of symmetric bursting phenomena can be observed in numerical simulations. Their dynamical behaviours are discussed by means of slow-fast analysis. Furthermore, the generalized Jacobian matrix at the non-smooth boundaries is introduced to explore the bifurcation mechanism for the bursting solutions, which can also be used to account for the evolution of the complicated structures of the phase portraits. With the variation of the parameter, the periodic symmetric bursting can evolve into chaotic symmetric bursting via period-doubling bifurcation. 展开更多
关键词 non-smooth electric circuit symmetric bursting bifurcation mechanism
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Research and Application of Non-symmetrical Roll Bending Control of Cold Rolling Mill 被引量:4
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作者 WANG Pengfei ZHANG Dianhua +2 位作者 LI Xu LIU Jiawei WANG Junsheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第1期122-127,共6页
The existing research of the flatness control for strip cold rolling mainly focuses on the calculation of the optimum adjustment of individual flatness actuator in accordance with the flatness deviation, which can be ... The existing research of the flatness control for strip cold rolling mainly focuses on the calculation of the optimum adjustment of individual flatness actuator in accordance with the flatness deviation, which can be used for general flatness control. However, it does not work for some special rolling processes, such as the elimination of ultra single side edge-waves and the prevention of strip break due to tilting roll control overshooting. For the purpose of solving these problems, the influences of non-symmetrical work roll bending and intermediate roll bending on flatness control were analyzed by studying efficiencies of them. Moreover, impacts of two kinds of non-symmetrical roll bending control on the pressure distribution between rolls were studied theoretically. A non-symmetrical work roll bending model was developed by theoretical analysis in accordance with practical conditions. The model was applied to the revamp of a 1250 6-H reversible universal crown mill (UCM) cold mill. Theoretical study and practical applications show that the coordination utilization of the non-symmetrical work roll bending control and tilting roll control was effective in flatness control when there appeared bad strip single side edge waves, especially when the incoming strip was with a wedge shape. In addition, the risk of strip break due to tilting control overshooting could be reduced. Furthermore, the non-symmetrical roll bending control can reduce the extent of uneven distribution of pressure between rolls caused by intermediate roll shifting in flatness control and slow down roll wear. The non-symmetrical roll bending control technology has important theoretical and practical significance to better flatness control. 展开更多
关键词 non-symmetrical roll bending flatness control cold rolling actuator efficiency roll wear strip break
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A NOTE ON PERTURBATION OF NON-SYMMETRIC DIRICHLET FORMS BY SIGNED SMOOTH MEASURES 被引量:3
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作者 陈传钟 《Acta Mathematica Scientia》 SCIE CSCD 2007年第1期219-224,共6页
This article discusses the perturbation of a non-symmetric Dirichlet form, (ε, D(ε)), by a signed smooth measure u, where u=u1 -u2 with u1 and u2 being smooth measures. It gives a sufficient condition for the pe... This article discusses the perturbation of a non-symmetric Dirichlet form, (ε, D(ε)), by a signed smooth measure u, where u=u1 -u2 with u1 and u2 being smooth measures. It gives a sufficient condition for the perturbed form (ε^u ,D(ε^u)) (for some a0 ≥ 0) to be a coercive closed form. 展开更多
关键词 non-symmetric Dirichlet form signed smooth measure perturbation of Dirichlet form generalized Feynman-Kac semigroup
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Derivative of a Determinant with Respect to an Eigenvalue in the <i>LDU</i>Decomposition of a Non-Symmetric Matrix 被引量:1
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作者 Mitsuhiro Kashiwagi 《Applied Mathematics》 2013年第3期464-468,共5页
We demonstrate that, when computing the LDU decomposition (a typical example of a direct solution method), it is possible to obtain the derivative of a determinant with respect to an eigenvalue of a non-symmetric matr... We demonstrate that, when computing the LDU decomposition (a typical example of a direct solution method), it is possible to obtain the derivative of a determinant with respect to an eigenvalue of a non-symmetric matrix. Our proposed method augments an LDU decomposition program with an additional routine to obtain a program for easily evaluating the derivative of a determinant with respect to an eigenvalue. The proposed method follows simply from the process of solving simultaneous linear equations and is particularly effective for band matrices, for which memory requirements are significantly reduced compared to those for dense matrices. We discuss the theory underlying our proposed method and present detailed algorithms for implementing it. 展开更多
关键词 DERIVATIVE of DETERMINANT non-symmetric MATRIX EIGENVALUE Band MATRIX LDU DECOMPOSITION
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Robust Stability of Nonlinear Plants with a Non-symmetric Prandtl-Ishlinskii Hysteresis Model 被引量:1
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作者 Akira Inoue 《International Journal of Automation and computing》 EI 2010年第2期213-218,共6页
In this paper, robust stability of nonlinear plants represented by non-symmetric Prandtl-Ishlinskii (PI) hysteresis model is studied. In general, PI hysteresis model is the weighted superposition of play or stop hys... In this paper, robust stability of nonlinear plants represented by non-symmetric Prandtl-Ishlinskii (PI) hysteresis model is studied. In general, PI hysteresis model is the weighted superposition of play or stop hysteresis operators, and the slopes of the operators are considered to be the same. In order to make a hysteresis model, a modified form of non-symmetric play hysteresis operator with unknown slopes is given. The hysteresis model is described by a generalized Lipschitz operator term and a bounded parasitic term. Since the generalized Lipschitz operator is unknown, a new condition using robust right coprime factorization is proposed to guarantee robust stability of the controlled plant with the hysteresis nonlinearity. As a result, based on the proposed robust condition, a stabilized plant is obtained. A numerical example is presented to validate the effectiveness of the proposed method. 展开更多
关键词 Prandtl-Ishlinskii (PI) hysteresis model robust stability right coprime factorization non-symmetric play hysteresis operator nonlinear plants.
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SYMMETRIC FORMULATION OF TANGENTIAL STIFFNESSES FOR NON-ASSOCIATED VISCOPLASTICITY WITH AN IMPLICIT TIME INTEGRATION SCHEME
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作者 熊文林 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第3期269-276,共8页
A numerical scheme is presented which enables the use of symmetric equation solvers in tangential stiffness programs for non-associated viscoplastic materials.
关键词 VISCOPLASTICITY non-associated tangential stiffnesses symmetric
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Experimental study of noncontact ultrasonic motor with non-symmetrical electrode
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作者 杨斌 刘景全 +2 位作者 陈迪 周伟民 蔡炳初 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第2期454-459,共6页
We have proposed a novel noncontact ultrasonic motor based on non-syinmetrical electrode driving. The configuration of this electrode and the fabrication process of rotors are presented. Its vibration characteristics ... We have proposed a novel noncontact ultrasonic motor based on non-syinmetrical electrode driving. The configuration of this electrode and the fabrication process of rotors are presented. Its vibration characteristics are computed and analysed by using the finite element method and studied experimentally. Good agreement between them is obtained. Moreover, it is also shown that this noncontact ultrasonic motor is operated in antisymmetric radial vibration mode of B21 mode. The maximum revolution speed for three-blade and six-blade rotors are 5100 and 3700r/min at an input voltage of 20V, respectively. Also, the noncontact high-speed revolution of the rotors can be realized by the parts of Ⅰ, Ⅲ of the electrode or Ⅱ, Ⅳ of the electrode. The levitation distance between the s tator and rotor is about 140μm according to the theoretical calculation and the experimental measurement. 展开更多
关键词 non-symmetrical electrode nonCONTACT travelling wave ultrasonic motor
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Basic solution of two parallel non-symmetric permeable cracks in piezoelectric materials
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作者 周振功 王彪 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第4期417-428,共12页
The behavior of two parallel non-symmetric cracks in piezoelectric materials subjected to the anti-plane shear loading was studied by the Schmidt method for the permeable crack electric boundary conditions. Through th... The behavior of two parallel non-symmetric cracks in piezoelectric materials subjected to the anti-plane shear loading was studied by the Schmidt method for the permeable crack electric boundary conditions. Through the Fourier transform, the present problem can be solved with two pairs of dual integral equations in which the unknown variables are the jumps of displacements across crack surfaces. To Solve the dual integral equations, the jumps of displacements across crack surfaces were directly expanded in a series of Jacobi polynomials. Finally, the relations between electric displacement intensity factors and stress intensity factors at crack tips can be obtained. Numerical examples are provided to show the effect of the distance between two cracks upon stress and electric displacement intensity factors at crack tips. Contrary to the impermeable crack surface condition solution, it is found that electric displacement intensity factors for the permeable crack surface conditions are much smaller than those for the impermeable crack surface conditions. At the same time, it can be found that the crack shielding effect is also present in the piezoelectric materials. 展开更多
关键词 piezoelectric materials parallel non-symmetric cracks dual-integral equations intensity factor
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Construction of Non-Symmetric Balanced Incomplete Block Design through Combination of Symmetric Disjoint Balanced Incomplete Block Designs
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作者 Troon John Benedict Onyango Fredrick +1 位作者 Karanjah Anthony Njuguna Edward 《Open Journal of Statistics》 2023年第6期789-802,共14页
The existence of several non-symmetric balanced incomplete block designs (BIBDs) is still unknown. This is because the non-existence property for non-symmetric BIBDs is still not known and also the existing constructi... The existence of several non-symmetric balanced incomplete block designs (BIBDs) is still unknown. This is because the non-existence property for non-symmetric BIBDs is still not known and also the existing construction methods have not been able to construct these designs despite their design parameters satisfying the necessary conditions for the existence of BIBD. The study aimed to bridge this gap by introducing a new class of non-symmetric BIBDs. The proposed class of BIBDs is constructed through the combination of disjoint symmetric BIBDs. The study was able to determine that the total number of disjoint symmetric BIBDs (n) with parameters (v = b, r = k, λ) that can be obtained from an un-reduced BIBD with parameters (v, k) is given by n = r - λ. When the n symmetric disjoint BIBDs are combined, then a new class of symmetric BIBDs is formed with parameters v<sup>*</sup><sup> </sup>= v, b<sup>*</sup><sup> </sup>= nb, r<sup>*</sup><sup> </sup>= nr, k<sup>*</sup><sup> </sup>= k, λ<sup>*</sup><sup> </sup>= λ, where 2≤ n ≤ r - λ. The study established that the non-existence property of this class of BIBD was that when is not a perfect square then v should be even and when v<sup>*</sup><sup> </sup>is odd then the equation should not have a solution in integers x, y, z which are not all simultaneously zero. In conclusion, the study showed that this construction technique can be used to construct some non-symmetric BIBDs. However, one must first construct the disjoint symmetric BIBDs before one can construct the non-symmetric BIBD. Thus, the disjoint symmetric BIBDs must exist first before the non-symmetric BIBDs exist. 展开更多
关键词 Disjoint symmetric BIBD Un-Reduced BIBD COMBINATION symmetric BIBD non-symmetric BIBD non-Existence of BIBD
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NON-SYMMETRICAL LARGE DEFORMATION OF A SHALLOW THIN SPHERICAL SHELL
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作者 王新志 任冬云 +1 位作者 王林祥 叶开沅 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第8期705-722,共18页
By the modified iteration method,in this paper,non=symmetrical large deflectionof a shallow spherical shell is discussed. We solve the second-order approximate analytical solution of the deflection of a shallow spheri... By the modified iteration method,in this paper,non=symmetrical large deflectionof a shallow spherical shell is discussed. We solve the second-order approximate analytical solution of the deflection of a shallow spherical shell subjected to linearliquid loads. and portray the characteristic curves of load-deflection on a perturbing point. With this paper's method, the similar questions of other kind of shell can bediscussed. Through the examples.we discuss the large defection of a plane and shallow spherical shells with different initial deflections. 展开更多
关键词 large deformation. non-symmetrical. iteration method
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Some Properties of <i>CR</i>-Submanifolds of a Nearly Trans-Sasakian Manifold with a Semi Symmetric Non-Metric Connection
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作者 Lovejoy S. Das Mobin Ahmad Abdul Haseeb 《Journal of Applied Mathematics and Physics》 2014年第8期813-822,共10页
This paper deals with the study of CR-submanifolds of a nearly trans-Sasakian manifold with a semi symmetric non-metric connection. Nijenhuis tensor, integrability conditions for some distributions on CR-submanifolds ... This paper deals with the study of CR-submanifolds of a nearly trans-Sasakian manifold with a semi symmetric non-metric connection. Nijenhuis tensor, integrability conditions for some distributions on CR-submanifolds of a nearly trans-Sasakian manifold with a semi symmetric non- metric connection are discussed. 展开更多
关键词 CR -Submanifolds NEARLY Trans-Sasakian Manifold SEMI symmetric non-Metric CONNECTION Distribution
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Chen’s Inequalities for Submanifolds in (<i>&kgreen;, &#181</i>)-Contact Space Form with a Semi-Symmetric Non-Metric Connection
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作者 Asif Ahmad Faisal Shahzad Jing Li 《Journal of Applied Mathematics and Physics》 2018年第2期389-404,共16页
In this paper, we obtain Chen’s inequalities in (k,?μ)-contact space form with a semi-symmetric non-metric connection. Also we obtain the inequalites for Ricci and K-Ricci curvatures.
关键词 (k µ)-Contact Space Form Semi-symmetric non-Metric CONNECTION Chen’s INEQUALITIES Ricci Curvature
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NON-SYMMETRICAL LARGE DEFORMATION OFA SHALLOW THIN CONICAL SHELL
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作者 王新志 赵永刚 叶开沅 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第10期917-928,共12页
In this paper, non-symmetrical large deformation problem of a shallow conical shell is studied by two-parameter perturbation method. The third-order approximate analytical solution of the deformation of a shallow coni... In this paper, non-symmetrical large deformation problem of a shallow conical shell is studied by two-parameter perturbation method. The third-order approximate analytical solution of the deformation of a shallow conical shell subjected to linear loads is obtained and the characteristic curves of load-deflection on a perturbing point are portrayed. The similar questions of other kind of shell and plate can be discussed by using this paper's method. As the examples, the large deflection of plate and shallow conical shells with different initial deflections is discussed. 展开更多
关键词 shallow thin conical shell non-symmetrical large deformation two-parameter perturbation method
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Voltage and Current Mode Vector Analyses of Correction Procedure Application to Clarke’s Matrix—Symmetrical Three-Phase Cases 被引量:1
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作者 Afonso José do PRADO Sérgio KUROKAWA +1 位作者 José Pissolato FILHO Luiz Fernando BOVOLATO 《Journal of Electromagnetic Analysis and Applications》 2010年第1期7-17,共11页
Clarke’s matrix has been applied as a phase-mode transformation matrix to three-phase transmission lines substituting the eigenvector matrices. Considering symmetrical untransposed three-phase lines, an actual symmet... Clarke’s matrix has been applied as a phase-mode transformation matrix to three-phase transmission lines substituting the eigenvector matrices. Considering symmetrical untransposed three-phase lines, an actual symmetrical three-phase line on untransposed conditions is associated with Clarke’s matrix for error and frequency scan analyses in this paper. Error analyses are calculated for the eigenvalue diagonal elements obtained from Clarke’s matrix. The eigenvalue off-diagonal elements from the Clarke’s matrix application are compared to the correspondent exact eigenvalues. Based on the characteristic impedance and propagation function values, the frequency scan analyses show that there are great differences between the Clarke’s matrix results and the exact ones, considering frequency values from 10 kHz to 1 MHz. A correction procedure is applied obtaining two new transformation matrices. These matrices lead to good approximated results when compared to the exact ones. With the correction procedure applied to Clarke’s matrix, the relative values of the eigenvalue matrix off-diagonal element obtained from Clarke’s matrix are decreased while the frequency scan results are improved. The steps of correction procedure application are detailed, investigating the influence of each step on the obtained two new phase-mode transformation matrices. 展开更多
关键词 Clarke’s Matrix EIGENVECTOR EIGENVALUE Phase Mode Transformation Error Analysis non symmetricAL LINES Frequency Dependent Parameters
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EXTENSION OF SMOOTHING FUNCTIONS TO SYMMETRIC CONE COMPLEMENTARITY PROBLEMS 被引量:2
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作者 Liu Yongjin Zhang Liwei Liu Meijiao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2007年第2期245-252,共8页
The paper uses Euclidean Jordan algebras as a basic tool to extend smoothing functions, which include the Chen-Mangasarian class and the Fischer-Burmeister smoothing functions, to symmetric cone complementarity proble... The paper uses Euclidean Jordan algebras as a basic tool to extend smoothing functions, which include the Chen-Mangasarian class and the Fischer-Burmeister smoothing functions, to symmetric cone complementarity problems. Computable formulas for these functions and their Jacobians are derived. In addition, it is shown that these functions are Lipschitz continuous with respect to parameter # and continuously differentiable on J × J for any μ 〉 0. 展开更多
关键词 symmetric cone complementarity problem smoothing function Euclidean Jordan algebra non-interior continuation method
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Robust Adaptive Control for a Class of Systems with Deadzone Nonlinearity 被引量:1
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作者 Nizar J. Ahmad Mahmud J. Alnaser +1 位作者 Ebraheem Sultan Khuloud A. Alhendi 《Intelligent Control and Automation》 2015年第1期10-19,共10页
This paper presents a robust adaptive control scheme for a class of continuous-time linear systems with unknown non-smooth asymmetrical deadzone nonlinearity at the input of the plant. The methodology is applied to ha... This paper presents a robust adaptive control scheme for a class of continuous-time linear systems with unknown non-smooth asymmetrical deadzone nonlinearity at the input of the plant. The methodology is applied to handle input deadzone as well as unmeasurable disturbances simultaneously in strictly matched systems. The proposed controller robustly cancels any residual distortion caused by the inaccurate deadzone cancellation scheme. The scheme is shown to successfully cancel the deadzone’s deleterious effect as well as eliminate other unmeasurable disturbances within the span of the input. The new controller ensures the global stability of all states and adaptations, and achieves asymptotic tracking. The asymptotic stability of the closed-loop system is proven by Lyapunov arguments, and simulation results confirm the efficacy of the control methodology. 展开更多
关键词 ADAPTIVE Control non-symmetric DEADZONE HARD nonLINEARITY
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