期刊文献+
共找到27篇文章
< 1 2 >
每页显示 20 50 100
Construction of Non-Symmetric Balanced Incomplete Block Design through Combination of Symmetric Disjoint Balanced Incomplete Block Designs
1
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
下载PDF
Research and Application of Non-symmetrical Roll Bending Control of Cold Rolling Mill 被引量:4
2
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
下载PDF
A NOTE ON PERTURBATION OF NON-SYMMETRIC DIRICHLET FORMS BY SIGNED SMOOTH MEASURES 被引量:3
3
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
下载PDF
Analysis of non-symmetrical flapping airfoils 被引量:2
4
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
下载PDF
Multi-party dense coding in non-symmetric quantum channel 被引量:2
5
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
下载PDF
Robust Stability of Nonlinear Plants with a Non-symmetric Prandtl-Ishlinskii Hysteresis Model 被引量:1
6
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.
下载PDF
Derivative of a Determinant with Respect to an Eigenvalue in the <i>LDU</i>Decomposition of a Non-Symmetric Matrix 被引量:1
7
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
下载PDF
Basic solution of two parallel non-symmetric permeable cracks in piezoelectric materials
8
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
下载PDF
Experimental study of noncontact ultrasonic motor with non-symmetrical electrode
9
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
下载PDF
NON-SYMMETRICAL LARGE DEFORMATION OF A SHALLOW THIN SPHERICAL SHELL
10
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
下载PDF
NON-SYMMETRICAL LARGE DEFORMATION OFA SHALLOW THIN CONICAL SHELL
11
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
全文增补中
Electrocatalytic Synthesis of Non-Symmetric Biphenols Mediated by Tri(p-bromophenyl)amine:Selective Oxidative Cross-Coupling of Different Phenols and Naphthols 被引量:2
12
作者 Qing-Qing Wang Yang-Ye Jiang +1 位作者 Cheng-Chu Zeng Bao-Guo Sun 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2019年第4期352-358,共7页
An efficient electrochemical access to the non-symmetric biphenols using tri(p-bromophenyl)amine(TBPA)as a redox mediator has been developed.The electrochemical protocol features highly selective cross-coupling produc... An efficient electrochemical access to the non-symmetric biphenols using tri(p-bromophenyl)amine(TBPA)as a redox mediator has been developed.The electrochemical protocol features highly selective cross-coupling products in up to 83% yield,instead of forming homo-coupling ones. 展开更多
关键词 non-symmetric Biphenols MEDIATED Tri(p-bromophenyl)amine PHENOLS NAPHTHOLS
原文传递
On notions of harmonicity for non-symmetric Dirichlet form
13
作者 MA ZhiMing1, ZHU RongChan1, & ZHU XiangChan2 1Institute of Applied Mathematics, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190, China 2School of Mathematical Sciences, Peking University, Beijing 100871, China 《Science China Mathematics》 SCIE 2010年第6期1407-1420,共14页
In this paper, we extend the equivalence of the analytic and probabilistic notions of harmonicity in the context of Hunt processes associated with non-symmetric Dirichlet forms on locally compact separable metric spac... In this paper, we extend the equivalence of the analytic and probabilistic notions of harmonicity in the context of Hunt processes associated with non-symmetric Dirichlet forms on locally compact separable metric spaces. Extensions to the processes associated with semi-Dirichlet forms and nearly symmetric right processes on Lusin spaces including infinite dimensional spaces are mentioned at the end of this paper. 展开更多
关键词 harmonic functions UNIFORMLY INTEGRABLE MARTINGALE SPV INTEGRABLE non-symmetric DIRICHLET forms non-symmetric Beurling-Deny decomposition HUNT processes
原文传递
Information Leakage in Quantum Dialogue by Using Non-Symmetric Quantum Channel
14
作者 高干 李伟艳 王悦 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第5期507-510,共4页
In this paper [Commun. Theor. Phys. 53(2010) 648], Zhan et al. proposed a quantum dialogue protocol by using non-symmetric quantum channel. We study the security of the protocol and find that it has the drawback of in... In this paper [Commun. Theor. Phys. 53(2010) 648], Zhan et al. proposed a quantum dialogue protocol by using non-symmetric quantum channel. We study the security of the protocol and find that it has the drawback of information leakage. That is, Zhan et al.'s protocol is proved to be insecure by us. 展开更多
关键词 information leakage SECURITY quantum dialogue non-symmetric quantum channel
原文传递
Stable and non-symmetric pitchfork bifurcations
15
作者 Enrique Pujals Michael Shub Yun Yang 《Science China Mathematics》 SCIE CSCD 2020年第9期1837-1852,共16页
In this paper,we present a criterion for pitchfork bifurcations of smooth vector elds based on a topological argument.Our result expands Rajapakse and Smale's result[15]signi cantly.Based on our criterion,we prese... In this paper,we present a criterion for pitchfork bifurcations of smooth vector elds based on a topological argument.Our result expands Rajapakse and Smale's result[15]signi cantly.Based on our criterion,we present a class of families of non-symmetric vector elds undergoing a pitchfork bifurcation. 展开更多
关键词 pitchfork bifurcation INDEX non-symmetric vector eld center manifold
原文传递
NON-SYMMETRIC ASSOCIATION SCHEMES OF SYMMETRIC MATRICES
16
作者 霍元极 万哲先 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 1993年第3期236-255,共20页
Let X_n be the set of n×n symmetric matrices over a finite field F_q,where q is a power of an odd prime.For S_1,S_2 ∈ X_n,we define (S_1,S_2)∈ R_0 iff S_1=S_2;(S_1,S_2)∈R_(r,ε)iff S_1-S_2 is congruent to wher... Let X_n be the set of n×n symmetric matrices over a finite field F_q,where q is a power of an odd prime.For S_1,S_2 ∈ X_n,we define (S_1,S_2)∈ R_0 iff S_1=S_2;(S_1,S_2)∈R_(r,ε)iff S_1-S_2 is congruent to where?=1 or z,z being afixed non-square element of F_q.Then X_n=(X_n,{R_0,R_(r,ε)|1≤r≤n,?=1 or z}) is a non-symmetric association scheme of class 2n on X_n.The parameters of X_n have been computed.And we also prove that X_n is commutative. 展开更多
关键词 non-symmetric ASSOCIATION SCHEMES OF SYMMETRIC MATRICES
原文传递
ON THE EXISTENCE AND UNIQUENESS THEOREMS OF SOLUTIONS FOR THE SYSTEMS OF MIXED MONOTONE OPERATOR EQUATIONS WITH APPLICATIONS 被引量:11
17
作者 张石生 郭伟平 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1993年第1期1-14,共14页
The existence, uniqueness and non-symmetric iterative approximation of solutions for a class of systems of mixed monotone operator equations are discussed. As an application, we utilize, the results presented in this ... The existence, uniqueness and non-symmetric iterative approximation of solutions for a class of systems of mixed monotone operator equations are discussed. As an application, we utilize, the results presented in this paper to study the existence and uniqueness problems of common solutions for a class of systems of functional equations arising in dynamic programming of multistage decision processes and a class of systems of nonlinear integral equation. The results obtained in this paper not only answer an open question suggested in [3] but also generalize the corresponding results of [1],[2]. 展开更多
关键词 Mixed Monotone Operator non-symmetric Iteration System of Functional Equations
下载PDF
A Two-Point Boundary Value Problem by Using a Mixed Finite Element Method
18
作者 Pedro Pablo Cárdenas Alzate José Rodrigo González Granada 《Applied Mathematics》 2015年第12期1996-2003,共8页
This paper describes a numerical solution for a two-point boundary value problem. It includes an algorithm for discretization by mixed finite element method. The discrete scheme allows the utilization a finite element... This paper describes a numerical solution for a two-point boundary value problem. It includes an algorithm for discretization by mixed finite element method. The discrete scheme allows the utilization a finite element method based on piecewise linear approximating functions and we also use the barycentric quadrature rule to compute the stiffness matrix and the L2-norm. 展开更多
关键词 TWO-POINT BVP Galerkin’s METHOD non-symmetric PROBLEM
下载PDF
Robust Adaptive Control for a Class of Systems with Deadzone Nonlinearity
19
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
下载PDF
Fourier time spectral method for subsonic and transonic flows
20
作者 Lei Zhan Feng Liu Dimitri Papamoschou 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第3期380-396,共17页
The time accuracy of the exponentially accurate Fourier time spectral method(TSM) is examined and compared with a conventional 2nd-order backward difference formula(BDF) method for periodic unsteady flows. In part... The time accuracy of the exponentially accurate Fourier time spectral method(TSM) is examined and compared with a conventional 2nd-order backward difference formula(BDF) method for periodic unsteady flows. In particular, detailed error analysis based on numerical computations is performed on the accuracy of resolving the local pressure coefficient and global integrated force coefficients for smooth subsonic and non-smooth transonic flows with moving shock waves on a pitching airfoil. For smooth subsonic flows, the Fourier TSM method offers a significant accuracy advantage over the BDF method for the prediction of both the local pressure coefficient and integrated force coefficients. For transonic flows where the motion of the discontinuous shock wave contributes significant higherorder harmonic contents to the local pressure fluctuations,a sufficient number of modes must be included before the Fourier TSM provides an advantage over the BDF method.The Fourier TSM, however, still offers better accuracy than the BDF method for integrated force coefficients even for transonic flows. A problem of non-symmetric solutions for symmetric periodic flows due to the use of odd numbers of intervals is uncovered and analyzed. A frequency-searching method is proposed for problems where the frequency is not known a priori. The method is tested on the vortex shedding problem of the flow over a circular cylinder. 展开更多
关键词 Fourier time spectral method(TSM) Pitching airfoil Transonic flow non-symmetric solution Computational efficiency Vortex shedding flow Frequency search
下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部